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1600 John F. Kennedy Blvd. Ste 1800 Philadelphia, PA 19103-2899 CLINICAL REPRODUCTIVE MEDICINE AND SURGERY Copyright © 2007 by Mosby, Inc., an affiliate of Elsevier Inc. All rights reserved. No part of this publication may be reproduced or transmitted in any form or by any means, electronic or mechanical, including photocopying, recording, or any information storage and retrieval system, without permission in writing from the publisher. Permissions may be sought directly from Elsevier’s Health Sciences Rights Department in Philadelphia, PA, USA: phone: (+1) 215 239 3804, fax: (+1) 215 239 3805, e-mail:
[email protected]. You may also complete your request on-line via the Elsevier homepage (http://www.elsevier.com), by selecting “Customer Support” and then “Obtaining Permissions.”
Notice Knowledge and best practice in this field are constantly changing. As new research and experience broaden our knowledge, changes in practice, treatment and drug therapy may become necessary or appropriate. Readers are advised to check the most current information provided (i) on procedures featured or (ii) by the manufacturer of each product to be administered, to verify the recommended dose or formula, the method and duration of administration, and contraindications. It is the responsibility of the practitioner, relying on his or her own experience and knowledge of the patient, to make diagnoses, to determine dosages and the best treatment for each individual patient, and to take all appropriate safety precautions. To the fullest extent of the law, neither the Publisher nor the Editors/Authors assume any liability for any injury and/or damage to persons or property arising out or related to any use of the material contained in this book.
Library of Congress Cataloging-in-Publication Data Clinical and reproductive medicine and surgery/[edited by] Tommaso Falcone, William W. Hurd p.; cm. ISBN-10: 0-323-03309-1 ISBN-13: 978-0-323-03309-1 1. Generative organs—Diseases. 2. Generative organs, Female—Diseases. 3. Infertility. 4. Human reproduction. I. Falcone, Tommaso. II. Hurd, William W. [DNLM: 1. Genital Diseases, Female. 2. Genital Diseases, Female–surgery. 3. Gynecologic Surgical Procedures–methods. 4. Reproductive Medicine–methods. WP 140 C6403 2007] RC875.C555 2007 616.65—dc22 2006048168
Acquisitions Editor: Rebecca Schmidt Gaertner Developmental Editors: Jennifer Ehlers and Christine Oberle Project Manager: Mary B. Stermel Design Direction: Louis Forgione Marketing Manager: Matt Latuchie Printed in Hong Kong Last digit is the print number: 9
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ISBN-13: ISBN-10:
978-0-323-03309-1 0-323-03309-1
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Contributors Cynthia Abacan, MD Fellow Department of Endocrinology, Diabetes, and Metabolism Cleveland Clinic Cleveland, Ohio Ashok Agarwal, PhD, HCLD Director Andrology Laboratory and Reproductive Tissue Bank; Director Reproductive Research Center; Professor Cleveland Clinic Lerner College of Medicine Case Western Reserve University; Glickman Urological Institute and Departments of Obstetrics and Gynecology, Anatomic Pathology, and Immunology Cleveland Clinic Cleveland, Ohio Raedah Al-Fadhli, MD Fellow Reproductive Endocrinology and Infertility McGill University Montreal, Quebec, Canada Shyam S.R. Allamaneni, MD Resident Department of General Surgery Saint Vincent Catholic Medical Center Jamaica, New York
Marjan Attaran, MD Head Section of Pediatric Gynecology Department of Obstetrics and Gynecology Cleveland Clinic Cleveland, Ohio Cynthia Austin, MD Department of Obstetrics and Gynecology Cleveland Clinic Cleveland, Ohio Jaswant S. Bal, MD, FRCOG, FACOG Assistant Clinical Professor Department of Obstetrics and Gynecology SUNY Health Science Center Syracuse, New York Sheela Barhan, MD Department of Obstetrics and Gynecology Wright State University School of Medicine Dayton, Ohio Kurt Barnhart, MD, MSCE Associate Professor of Obstetrics and Gynecology and Epidemiology Penn Fertility Care University of Pennsylvania Philadelphia, Pennsylvania
Lawrence S. Amesse, MD, PhD Department of Obstetrics and Gynecology Wright State University School of Medicine Dayton, Ohio
Kshonija Batchu, MD Research Assistant Division of Reproductive Endocrinology and Infertility Department of Obstetrics and Gynecology Stanford University School of Medicine Stanford, California
Aydin Arici, MD Professor Department of Obstetrics and Gynecology Yale University School of Medicine New Haven, Connecticut
Mohamed A Bedaiwy, MD Fellow Department of Obstetrics and Gynecology Cleveland Clinic Cleveland, Ohio
Francisco Arredondo, MD, MPH Department of Obstetrics and Gynecology University Hospitals of Cleveland Cleveland, Ohio
Sarah L. Berga, MD Professor and Chair Department of Obstetrics and Gynecology Emory University School of Medicine Atlanta, Georgia
Khalid Ataya, MD Professor Department of Obstetrics and Gynecology MetroHealth Medical Center Cleveland, Ohio
Charles V. Biscotti, MD Department of Anatomic Pathology Cleveland Clinic Cleveland, Ohio
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Contributors
Linda D. Bradley, MD Department of Obstetrics and Gynecology Cleveland Clinic Cleveland, Ohio
Miriam Delaney, MD Department of Rheumatic and Immunologic Disease Cleveland Clinic Cleveland, Ohio
Ronald T. Burkman, MD Chairman Department of Obstetrics and Gynecology Baystate Medical Center Springfield, Massachusetts; Deputy Chair and Professor Department of Obstetrics and Gynecology Tufts University School of Medicine Boston, Massachusetts
Nina Desai, PhD Assistant Professor Director In Vitro Fertilization Laboratories Department of Obstetrics and Gynecology Cleveland Clinic Cleveland, Ohio
John Carey, MD Department of Rheumatic and Immunologic Disease Cleveland Clinic Cleveland, Ohio Allison M. Case, MD Department of Obstetrics and Gynecology Royal University Hospital Saskatoon, Saskatchewan, Canada Robert F. Casper, MD Professor Toronto Center for A.R.T. Toronto, Ontario, Canada SuYnn Chia, MD Department of Endocrinology Cleveland Clinic Cleveland, Ohio Gregory M. Christman, MD Associate Professor of Obstetrics and Gynecology Division of Reproductive Endocrinology and Infertility University of Michigan Medical School; Associate Professor Reproductive Sciences Program Department of Obstetrics and Gynecology University of Michigan Health System Ann Arbor, Michigan Brian Clark, MD, PhD Professor Department of Obstetrics and Gynecology Magee-Womens Hospital Center for Medical Genetics Pittsburgh, Pennsylvania Damon Davis, MD Resident Department of Urology University of Michigan Medical School Ann Arbor, Michigan
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Anne S. Devi Wold, MD Reproductive Research Center Lexington, Massachusetts Michael P. Diamond, MD Associate Chair and Kamran S. Moghissi Professor of Obstetrics and Gynecology Division of Reproductive Endocrinology and Infertility Department of Obstetrics and Gynecology Wayne State University Detroit, Michigan Richard L. Drake, PhD Professor Department of Education Cleveland Clinic Cleveland, Ohio Janice Duke, MD Department of Obstetrics and Gynecology Wright State University School of Medicine Dayton, Ohio Kristin A. Englund, MD Department of Infectious Disease Cleveland Clinic Cleveland, Ohio Navid Esfandiari, DVM, PhD, ELD, HCLD Director IVF, Andrology and Research Laboratories Toronto Center for A.R.T. Toronto, Ontario, Canada Charles Faiman, MD Department of Endocrinology Cleveland Clinic Cleveland, Ohio Tommaso Falcone, MD Professor and Chairman Department of Obstetrics and Gynecology Cleveland Clinic Cleveland, Ohio
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Contributors
Stephanie Fisher MD, FRCS(C) Assistant Professor Department of Obstetrics and Gynecology University of British Columbia Vancouver, British Columbia, Canada
Gary M. Horowitz, MD Associate Professor Department of Obstetrics and Gynecology Southern Illinois School of Medicine Springfield, Illinois
Maria Fleseriu, MD Assistant Professor Division of Endocrinology, Diabetes, and Clinical Nutrition Oregon Health and Sciences University Portland, Oregon
Elizabeth M. Hurd, RN, BSN Lactation Consultant Miami Valley Hospital Dayton, Ohio
Margo Fluker MD, FRCS(C) Co-Director Genesis Fertility Center; Clinical Professor Department of Obstetrics and Gynecology University of British Columbia Vancouver, British Columbia, Canada Gita Gidwani, MD Department of Obstetrics and Gynecology Cleveland Clinic Cleveland, Ohio Jeffrey M. Goldberg, MD Department of Obstetrics and Gynecology Cleveland Clinic Cleveland, Ohio James Goldfarb, MD, MBA Clinical Professor Beachwood Family Health Center Cleveland Clinic Beachwood, Ohio Dorothy Greenfeld, MSW, LCSW Associate Professor Department of Obstetrics, Gynecology, and Reproductive Sciences Yale University Fertility Center Yale University School of Medicine New Haven, Connecticut
William W. Hurd, MD, MS Professor of Obstetrics and Gynecology and Community Health Department of Obstetrics and Gynecology Wright State University School of Medicine Dayton, Ohio Shahryar K. Kavoussi, MD, MPH Fellow Division of Reproductive Endocrinology and Infertility Department of Obstetrics and Gynecology University of Michigan Health System Ann Arbor, Michigan Elizabeth Ann Kennard, MD Ohio Reproductive Medicine Columbus, Ohio Harry J. Khamis, PhD Director and Professor Statistical Consulting Center Wright State University Dayton, Ohio Peter N. Kolettis, MD Division of Urology University of Alabama at Birmingham Birmingham, Alabama Layne Kumetz, MD House Officer Department of Obstetrics and Gynecology Cedars-Sinai Medical Center Los Angeles, California
Manjula K. Gupta, PhD Department of Clinical Pathology Cleveland Clinic Cleveland, Ohio
William H. Kutteh, MD, PhD, HCLD Division of Reproductive Endocrinology University of Tennessee Memphis, Tennessee
Robert Hemmings, MD OVO Clinic Montreal, Quebec, Canada
Steven R. Lindheim, MD Department of Obstetrics and Gynecology University of Wisconsin Madison, Wisconsin
Melissa Hiner, BS Embryologist Department of Obstetrics and Gynecology University of Michigan Medical School Ann Arbor, Michigan
Hanna Lisbona, MD Department of Obstetrics and Gynecology Cleveland Clinic Cleveland, Ohio
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Contributors
James H. Liu, MD Arthur H. Bill Professor and Chair Department of Obstetrics and Gynecology University Hospitals/MacDonald Women’s Hospital; Department of Reproductive Biology Case School of Medicine Cleveland, Ohio J. Ricardo Loret de Mola, MD Department of Obstetrics and Gynecology University Hospitals of Cleveland Cleveland, Ohio Tammy L. Loucks, MPH Director of Clinical Research Department of Obstetrics and Gynecology Emory University School of Medicine Atlanta, Georgia Andrea Magen, MD Department of Radiology Cleveland Clinic Cleveland, Ohio
Pasquale Patrizio, MD, MBe Yale Fertility Center Yale University New Haven, Connecticut Teresa Pfaff-Amesse, MD Assistant Professor, Departments of Pathology and Neuroscience, Cell Biology, and Physiology Wright State University School of Medicine Dayton, Ohio Barry Peskin, MD Department of Obstetrics and Gynecology Cleveland Clinic Cleveland, Ohio
Neal Gregory Mahutte, MD Assistant Professor Reproductive Endocrinology and Infertility Dartmouth Medical School Lebanon, New Hampshire
Susanne A. Quallich, NP Nurse Practitioner Division of Andrology and Microsurgery Department of Urology University of Michigan Ann Arbor, Michigan
Beth A. Malizia, MD Fellow Reproductive Endocrinology and Fertility Beth Israel Deaconess Medical Center Boston, Massachusetts
S. Sethu K. Reddy, MD Department of Endocrinology, Diabetes, and Metabolism Cleveland Clinic Cleveland, Ohio
Mohamed F. Mitwally, MD Clinical Assistant Professor Department of Obstetrics and Gynecology Wayne State University Detroit, Michigan
Robert L. Reid, MD Department of Obstetrics and Gynecology Queen’s University Kingston General Hospital Kingston, Ontario, Canada
Dana A. Ohl, MD Professor of Urology Department of Urology Head Division of Andrology and Microsurgery University of Michigan Ann Arbor, Michigan
Ellen S. Rome, MD Department of Pediatric and Adolescent Medicine Cleveland Clinic Cleveland, Ohio
Sophia Ouhilal, MD Assistant Professor Reproductive Endocrinology and Infertility Dartmouth Medical School Lebanon, New Hampshire
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John K. Park, MD Division of Reproductive Endocrinology and Fertility Department of Obstetrics and Gynecology Emory University School of Medicine Atlanta, Georgia
Kelly Pagidas, MD Department of Reproductive Medicine Women and Infants Hospital Providence, Rhode Island
Jonathan Ross, MD Glickman Urological Institute Cleveland Clinic Cleveland, Ohio Joseph S. Sanfilippo, MD, MBA Professor, Obstetrics-Gynecology and Reproductive Sciences University of Pittsburgh School of Medicine; Vice Chairman, Reproductive Sciences Division Director, Reproductive Endocrinology Residency Program Director Magee-Womens Hospital Pittsburgh, Pennsylvania
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Contributors
Erin J. Saunders, MD Clinical Professor Department of Obstetrics and Gynecology Vanderbilt University Nashville, Tennessee Timothy G. Schuster, MD Assistant Professor Department of Urology Division of Andrology and Microsurgery University of Michigan Ann Arbor, Michigan Beata Seeber, MD Department of Obstetrics and Gynecology University of Pennsylvania Philadelphia, Pennsylvania; Department of Gynecologic Endocrinology and Reproductive Medicine Medical University of Innsbruck Innsbruck, Austria Rakesh K. Sharma, PhD Center for Advanced Research in Human Reproduction, Infertility, and Sexual Function Glickman Urological Institute Department of Obstetrics and Gynecology Cleveland Clinic Cleveland, Ohio Howard T. Sharp, MD Department of Obstetrics and Gynecology University of Utah Medical Center Salt Lake City, Utah Cristine Silva, BS Embryologist Department of Obstetrics and Gynecology University of Michigan Medical School Ann Arbor, Michigan Gary D. Smith, MD Department of Obstetrics and Gynecology University of Michigan Medical School Ann Arbor, Michigan Jonathon M. Solnik, MD Director Minimally Invasive Gynecologic Surgery Department of Obstetrics and Gynecology Cedars-Sinai Medical Center; Assistant Professor Department of Obstetrics and Gynecology The David Geffen School of Medicine at UCLA Los Angeles, California Michael P. Steinkampf, MD Director Alabama Fertility Specialists Birmingham, Alabama
Thomas G. Stovall, MD Women’s Health Specialists Germantown, Tennessee Holly L. Thacker, MD, FACP Director Women’s Health Center Departments of Internal Medicine and Obstetrics and Gynecology Cleveland Clinic Cleveland, Ohio Geoffrey D. Towers, MD Assistant Professor Department of Obstetrics and Gynecology Wright State University Dayton, Ohio Togas Tulandi, MD, MHCM Professor and Chief of Obstetrics and Gynecology, JGH Department of Obstetrics and Gynecology Milton Leong Chair in Reproductive Medicine McGill University Montreal, Quebec, Canada Meike L. Uhler, MD Clinical Associate Professor Department of Obstetrics and Gynecology Loyola University School of Medicine Maywood, Illinois; Fertility Centers of Illinois Chicago, Illinois Joseph C. Veniero, MD Department of Radiology Cleveland Clinic Cleveland, Ohio Gary Ventolini, MD Associate Professor Department of Obstetrics and Gynecology Wright State University Dayton, Ohio James L. Whiteside, MD Department of Obstetrics and Gynecology Dartmouth-Hitchcock Medical Center Lebanon, New Hampshire Mylene W. M. Yao, MD Assistant Professor Division of Reproductive Endocrinology and Infertility Department of Obstetrics and Gynecology Stanford University School of Medicine Stanford, California
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Preface Reproductive medicine and surgery have together evolved into a distinctive field of modern gynecology. The focus of this field is on the identification and restoration of medical and anatomic abnormalities affecting the human reproductive system. Replacement therapy and more extensive surgery are now used only when required, since natural reproductive function is often more effective and safer than the best artificial replacement techniques. The knowledge gained in reproductive sciences over the last half of the 20th century is truly remarkable, and encyclopedic volumes have been written as a result. These distinguished works, however, deal primarily with the medical aspects of reproduction, and little has been written about the surgical aspects. This book is unique in that it includes both medical and surgical treatments, an approach we believe to be more reflective of the clinical practice of reproductive medicine. When compiling this text, we focused on two goals. The first was to provide a comprehensive review of all facets of clinical reproductive medicine and surgery. This review encompasses basic science and pathophysiology, clinical diagnosis and imaging, and medical and surgical treatment approaches. The second, and perhaps more challenging goal, was to create a book designed to be read rather than a reference work to be reserved for consultation. To this end, we diligently organized information provided
by many experts into 53 understandable and consistent chapters. We hope this book serves as a concise knowledge base for those in training and in the early years of practice, especially those planning to take comprehensive examinations on this information. With these goals in mind, we divided the book into seven parts. The first deals with basic science, covering the classic topics of neurophysiology, gametogenesis, fertilization and genetics, as well as anatomy, histology, statistics, and bioethics. The clinical medicine section has three parts that cover pediatric, adolescent and adult clinical reproductive medicine and infertility for both men and women. There are separate sections that cover the broad areas of female contraception and imaging. The final section deals with reproductive surgery performed to maintain fertility. Since visualization is an important part of learning surgery, a number of instructive video presentations on compact disk are included to reinforce the text. We hope that this book weaves together the elements of basic, clinical, and surgical science in such a way that the reader emerges with both a broad understanding of the basic science of reproductive medicine and a comprehensive approach to the reproductive patient. TOMMASO FALCONE BILL HURD
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Section 1 Basic Science Chapter
1
The Hypothalamic-Pituitary-Ovarian Axis and Control of the Menstrual Cycle Neal Gregory Mahutte and Sophia Ouhilal
INTRODUCTION The hypothalamus and pituitary gland form a unit that exerts control over a wide range of endocrine organs, including the gonads. This chapter describes the hypothalamic-pituitary-ovarian axis and control of the menstrual cycle, which is modulated by the central nervous system, other endocrine systems, and the environment. Key hormones in the hypothalamic-pituitary-ovarian axis include gonadotropin-releasing hormone (GnRH), folliclestimulating hormone (FSH), luteinizing hormone (LH), estradiol, and progesterone (Table 1-1). Supporting roles are also played by inhibin, activin, follistatin, and endorphins.
THE HYPOTHALAMUS The hypothalamus forms the lower part of the lateral wall and the floor of the third ventricle, and weighs approximately 10 grams. The hypothalamus is typically divided into eight specific nuclei (consistently clustered groups of neurons) and three areas (less clustered, less distinctly demarcated neurons), as illustrated in Figure 1-1. From a reproductive standpoint, the most important of these are the arcuate nucleus and the preoptic area, the principal sites of GnRH-producing neurons.1 The arcuate nucleus is located in the medial basal hypothalamus and is the most proximal of all the hypothalamic nuclei to the optic chiasm and the pituitary stalk. The arcuate nucleus is also the site of dopamine-secreting neurons that function to inhibit pituitary prolactin secretion and neurons that secrete growth hormone-releasing hormone.
Neurosecretory cell products from the hypothalamus, including GnRH, are released into the portal system from the median eminence, a prominence in the pituitary stalk at the floor of the third ventricle. The portal system serves as the major route of communication between the hypothalamus and the anterior pituitary. In contrast, the pituitary stalk (infundibulum) directly connects neuronal cell bodies in the hypothalamus to the posterior pituitary. The pituitary stalk lies immediately posterior to the optic chiasm.
GnRH GnRH is the primary hypothalamic regulator of pituitary reproductive function. Two human forms of GnRH (GnRH-I and GnRH-II) have been identified.2,3 Both are decapeptides and are the products of different genes. At least 20 other types of GnRH have been identified in fish, amphibians and protochordates, but none of these are believed to be present in humans.4,5 GnRH-I was first characterized and synthesized in 1971 by Andrew Schally and Roger Guillemin, an accomplishment for which both men ultimately received the Nobel prize.6–9 The structure of GnRH-I is common to all mammals, and its action is similar in males and females (Fig. 1-2). GnRH-I is synthesized from a much larger, 92-amino acid precursor peptide that contains GnRH-associated peptide.10 GnRH-I then travels along an axonal pathway called the tuberoinfundibular tract to the median eminence of the hypothalamus, where it is released into
Table 1-1 Major Hormones of the Hypothalamic-pituitary-ovarian Axis Hormone
Structure
Gene Location
Major Site(s) of Production
Half-Life
Serum Concentration
GnRH
Decapeptide
8p21-8p11.2
Arcuate nucleus of hypothalamus
2–4 min
N/A
FSH
Glycoprotein with α and β subunits
α: 6q12.2 β: 11p13
Gonadotrophs of anterior pituitary
1.5–4 hr
5–25 mIU/mL
LH
Glycoprotein with α and β subunits
α: 6q12.21 β: 19q12.32
Gonadotrophs of anterior pituitary
20–30 min
5–25 mIU/mL
Estradiol
18-carbon steroid
N/A
Granulosa cells
2–3 hr
20–400 pg/mL
Progesterone
21-carbon steroid
N/A
Theca-lutein cells
5 min
0.1–30 ng/mL
Inhibin
Peptide with α and β subunits Inhibin A= α + βA Inhibin B= α + βB
α: 2q33 βA: 2q13 βB: 7p15
Granulosa cells
30–60 min
A: 10–60 pg/mL B: 10–150 pg/mL
GnRH = gonadotropin-releasing hormone; FSH = follicle-stimulating hormone; LH = luteinizing hormone; N/A = not available
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Section 1 Basic Science
DH
PV
DM
PA
AH
VM
Hypothalamus PH
PM LM
MM
SO SC
Arcuate nucleus
Superior hypophyseal artery Optic chiasm Median eminence Middle hypophyseal artery Portal circulation
Inferior hypophyseal artery
Internal carotid artery Anterior pituitary
Sphenoid sinus
Posterior pituitary
Sella turcica
Figure 1-1 Illustration of the hypothalamus, pituitary, sella turcica, and portal system. The arcuate nucleus is the primary site of neurons that produce gonadotropin-releasing hormone (GnRH). GnRH is released from the median eminence into the portal system. The blood supply of the pituitary gland derives from the internal carotid arteries. In addition to the arcuate nucleus, the other hypothalamic nuclei are SO, supraoptic nucleus; SC, suprachiasmatic nucleus; PV, paraventricular nucleus; DM, dorsal medial nucleus; VM, ventromedial nucleus; PH, posterior hypothalamic nucleus; PM, premammillary nucleus; LM, lateral mammillary nucleus; MM, medial mammillary nucleus. The three hypothalamic areas are PA, preoptic area; AH, anterior hypothalamic area; DH, dorsal hypothalamic area.
pyro
Glu 1
Hi
s2 p Tr
3
7
Ser 4
Figure 1-2
2
6
Tyr5
Gly
Leu
Arg8
Pro9
Gly10
NH2
Structure of GnRH-I.
the portal circulation in a pulsatile fashion. The half-life of GnRH-I is very short (2 to 4 minutes) because it is rapidly cleaved between amino acids 5 and 6, 6 and 7, and 9 and 10. Because of its short half-life and rapid dilution in the peripheral
circulation, serum GnRH-I levels are difficult to measure and do not correlate with pituitary action. GnRH-I has three principal actions on anterior pituitary gonadotrophs: (1) synthesis and storage of gonadotropins, (2) movement of gonadotropins from the reserve pool to a point where they can be readily released, and (3) direct secretion of gonadotropins. GnRH-I pulses occur in response to intrinsic rhythmic activity within GnRH neurons in the arcuate nucleus. Pulsatile release of GnRH-I from the median eminence within a critical frequency and amplitude results in normal gonadotropin secretion.11,12 Continuous, rather than pulsatile, exposure to GnRH-I results in suppression of FSH and LH secretion and suppression of gonadotropin gene transcription.13,14
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Chapter 1 The Hypothalamic-Pituitary-Ovarian Axis and Control of the Menstrual Cycle Table 1-2 Menstrual Cycle Variation in LH Pulse Frequency and Amplitude Cycle Phase
Mean Frequency (minutes)
Early follicular
90
Mean Amplitude (mIU/mL) 6.5
Mid-follicular
50
5
Late follicular
60–70
7
Early luteal
100
15
Mid-luteal
150
12
Late luteal
200
8
Table 1-3 Neurotransmitter Effects on GnRH Release Neurotransmitter
Effect
Dopamine
Inhibits GnRH release
Endorphin
Inhibits GnRH release
Serotonin
Inhibits GnRH release
Norepinephrine, epinephrine
Stimulates GnRH release
In the absence of gonadal feedback, the GnRH pulse frequency is approximately once per hour.15 During the menstrual cycle the frequency and amplitude of GnRH pulses vary in response to hypothalamic feedback (Table 1-2).16 In general, the follicular phase is characterized by high-frequency, low-amplitude pulses, and the luteal phase is characterized by lower-frequency, higheramplitude pulses.17,18 However, considerable variability exists both between and within individuals.19 In humans, GnRH-I pulse frequency and amplitude are best approximated by measuring LH pulse frequency and amplitude. GnRH-II is most highly expressed outside of the brain, in tissues that include kidneys, bone marrow, and prostate. This is in contrast to GnRH-I, which is not expressed in high levels outside the brain. Although GnRH-II can induce release of both FSH and LH, it appears to have a wide array of physiologic functions outside the brain including regulation of cellular proliferation and mediation of ovarian and placental hormone secretion.20 Initial attempts in the mid-1990s to identify estrogen receptors in GnRH neurons were unsuccessful.21,22 However, subsequent use of more sophisticated techniques identified estrogen receptors α and β in the arcuate nucleus.23–26 Both receptors mediate estrogen action on GnRH neurons in vivo.27,28 The GnRH gene contains a hormone response element for the estrogen–estrogen receptor complex.29 Transcription of GnRH-I and GnRH-II is differentially regulated by estrogen.30 The regulatory role of estradiol on GnRH is complex. Estrogen inhibits GnRH gene expression/biosynthesis, but secretion of GnRH may be increased, decreased, or unaffected.31,32 The activity of the hypothalamus is further modulated by nervous stimuli from higher brain centers. GnRH neurons exhibit many connections to each other and to other neurons. Some of the neurotransmitters that modulate GnRH secretion are outlined in Table 1-3. The effects of these neurotransmitters help explain the mechanism by which certain physical or clinical conditions may affect the menstrual cycle (Table 1-4).
Table 1-4 Mechanisms for Oligo/amenorrhea in Various Clinical Conditions Hyperprolactinemia
Elevated dopamine suppresses GnRH
Hypothyroidism
Elevated TRH increases prolactin, which in turn increases dopamine which, then suppresses GnRH
Stress
Increased corticotropin (ACTH) results in increased endorphins (both are derived from the same peptide precursor); endorphins suppress GnRH
Exercise
Increased endorphins suppress GnRH
TRH = thyrotropin-releasing hormone; GnRH = gonadotropin-releasing hormone.
Cells that produce GnRH originate embryologically from the olfactory area.33 GnRH neurons, like olfactory epithelial cells of the nasal cavity, have cilia.34 During embryogenesis GnRH neurons migrate from the medial olfactory placode to the arcuate nucleus of the hypothalamus.35 The common origin of GnRH and olfactory neurons is demonstrated by Kallmann’s syndrome, where GnRH deficiency is associated with anosmia. Kallmann’s syndrome is believed to be caused by a variety of gene defects that affect neuronal cell migration.36 The common origin of GnRH and olfactory neurons is also suggestive of the relationship between pheromones and menstrual cyclicity. Pheromones are small airborne chemicals that when secreted externally by one individual may be perceived by other individuals of the same species, producing a change in sexual or social behavior. It is well recognized that women who work or live together often develop synchrony of their menstrual cycles.37 Moreover, it has been shown that odorless compounds from the axillae of cycling women can alter the cycle characteristics of recipient women.38 Presumably, these alterations occur through olfactory GnRH-mediated mechanisms.
The GnRH Receptor The GnRH-I receptor is a G-protein receptor that utilizes inositol triphosphate and diacylglycerol as second messengers to stimulate protein kinase, release of calcium ions, and cyclic adenosine monophosphate (cAMP) activity. The GnRH-I receptor is encoded by a gene on chromosome 14q21.1 and is expressed in many parts of the body outside of the brain, including ovarian follicles and the placenta. In humans it appears that GnRH-II signaling occurs through the GnRH-I receptor.5 Although a GnRH-II receptor is present in many mammalian species, its functional capacity is limited due to a frame shift and a stop codon. GnRH receptors are regulated by many substances, including GnRH itself, inhibin, activin, estrogen, and progesterone. Changes to the amino acid sequence of GnRH can extend its half-life to hours or days and can change its biologic activity from an agonist to an antagonist. All of the GnRH agonists currently available extend their half-life by substitutions at amino acid 6 and sometimes amino acid 10 of native GnRH (Table 1-5). Continuous activation of the GnRH receptor results in desensitization due to phosphorylation and conformational change of the receptor, uncoupling from G proteins, internalization of the receptor via endocytosis, and decreased receptor synthesis.39,40 On administration all GnRH agonists increase gonadotropin secretion (the flare effect). However, after 7 to 14 days GnRH receptor desensitization occurs and pituitary suppression is achieved.
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Section 1 Basic Science Table 1-5 Properties of Commercially Available GnRH Agonists
Agonist
Structure and Substitutions at Position 6 and 10
Half-Life
Relative Potency
Route of Administration
GnRH
Native decapeptide
2–4 min
1
IV, SC
Naferelin
Decapeptide 6: Nal for Gly
3–4 hr
200
Intranasal
Triptorelin
Decapeptide 6: Trp for Gly
3–4 hr
36–144
SC, IM depot
Leuprolide
Nonapeptide 6: Leu for Gly 10: NHEt for Gly
1.5 hr
50–80
SC, IM depot
Buserelin
Nonapeptide 6: Ser(OtBu) for Gly 10: NHEt for Gly
1.5 hr
20–40
SC, intranasal
Goserelin
Decapeptide 6: Ser(OtBu) for Gly 10: AzaGly for Gly
4.5 hr
50–100
SC implant
Histrelin
Decapeptide 6: DHis for Gly 10: AzaGly for Gly
50 min
100
SC
that recombines in long portal veins draining down the pituitary stalk to the anterior pituitary, where they break up into another capillary network. The blood supply of the posterior pituitary (neurohypophysis) comes from the middle and inferior hypophyseal arteries. Veins from these arteries drain into the cavernous sinuses, from which they ultimately reach the petrosal sinuses and then the jugular veins. The posterior pituitary is best understood as a continuation of the hypothalamus. The posterior pituitary is a direct downgrowth of nervous tissue from the hypothalamus through the pituitary stalk. The posterior pituitary is composed of glial tissue and axonal termini that secrete oxytocin and arginine vasopressin (AVP, also known as antidiuretic hormone). Oxytocin is synthesized in the paraventricular nucleus of the hypothalamus, whereas AVP is synthesized in the supraoptic nucleus, just above the arcuate nucleus. Oxytocin and AVP pass down the length of the pituitary stalk and are stored in terminal parts of axons in the posterior pituitary. Both oxytocin and AVP consist of nine amino acid residues (nonapeptides). Release of oxytocin and AVP is controlled directly by nervous impulses passing down the axons from the hypothalamus.
The Anterior Pituitary In contrast, GnRH antagonists directly inhibit gonadotropin secretion. Structurally, GnRH antagonists are characterized by multiple amino acid substitutions to the natural GnRH decapeptide. The commercially available GnRH antagonists cetrorelix and ganirelix have large amino acid additions to position 1 of native GnRH. GnRH antagonists compete for and occupy pituitary GnRH receptors, thus competitively blocking endogenous GnRH–GnRH receptor binding. In contrast to GnRH agonists, there is no flare effect with GnRH antagonists. Because receptor loss does not occur, a constant supply of antagonist is necessary to ensure that all GnRH receptors are continuously occupied. Thus, the therapeutic dosage range for antagonists is typically higher than that for agonists (mg versus μg).
THE PITUITARY
4
The pituitary gland measures approximately 15 × 10 × 6 mm and weighs approximately 500 to 900 mg. The pituitary gland lies immediately beneath the third ventricle and just above the sphenoidal sinus in a bony cavity called the sella turcica (Turkish saddle). It consists of anterior and posterior lobes, each having different embryologic origins, functions, and control mechanisms (Fig. 1-3). The secretion of pituitary hormones is controlled primarily by the hypothalamus. However, the activity of the hypothalamus and pituitary are modulated by nervous stimuli from higher brain centers and feedback from circulating hormones. There is no direct nervous connection between the hypothalamus and the anterior pituitary gland. Instead, communication occurs via the hypothalamic-pituitary portal system. The arterial blood supply of the pituitary is derived from branches of the internal carotid artery. The anterior pituitary gland is the most richly vascularized of all mammalian tissues. The blood supply of the anterior pituitary comes from the superior hypophyseal artery. The superior hypophyseal artery forms a capillary network in the median eminence of the hypothalamus
The anterior pituitary arises from an epithelial upgrowth from the roof of the primitive oral cavity (Rathke’s pouch). The anterior pituitary wraps around the posterior pituitary and constitutes two thirds of the volume of the pituitary gland. The portion of Rathke’s pouch in direct contact with the posterior pituitary develops less extensively than the rest of the anterior pituitary and is termed the pars intermedia. The major cell types of the anterior pituitary are outlined in Table 1-6. The anterior pituitary is a classic endocrine gland in that it is composed of secretory cells of epithelial origin supported by connective tissue rich in blood and lymphatic capillaries. In accordance with their active synthetic function the endocrine cells are characterized by prominent nuclei and prolific mitochondria, endoplasmic reticulum, Golgi bodies, and secretory vesicles. Synthesis of gonadotropins takes place in the rough endoplasmic reticulum, after which the hormones are packaged within the Golgi apparatus and stored as secretory granules. In response to GnRH the secretory granules are extruded from the cell membrane. The endothelial lining of capillary sinusoids is fenestrated, facilitating the passage of pituitary hormones into the sinusoids.
Gonadotropins The anterior pituitary secretes two hormones that stimulate the growth and activity of the gonads, FSH and LH. These glycoprotein hormones, termed gonadotropins, work in conjunction to stimulate secretion of steroid hormones from the ovary. FSH
FSH is a glycoprotein with a molecular weight of approximately 29,000 daltons. It consists of both an α and β subunit. The α subunit consists of 92 amino acids stabilized by 5 disulfide bonds and is identical to the α subunit of LH, thyroid-stimulating hormone (TSH) and human chorionic gonadotropin (hCG). The β subunit contains 118 amino acids and 5 sialic acid residues. Neither subunit has any intrinsic biologic activity by itself.
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A D
B
E Figure 1-3 X-ray and T1-weighted magnetic resonance images (MRI) of the pituitary gland. A, Lateral skull film with the sphenoidal sinus and sella turcica. B, Sagittal section demonstrating the relationship between the sphenoidal sinus and the pituitary gland. The normal posterior pituitary is brighter on MRI compared to the anterior pituitary. The sella turcica is not well seen on MRI. C, Sagittal section after administration of gadolinium contrast. Because the pituitary lies outside the blood-brain barrier, both the anterior and posterior pituitary are illuminated with the contrast. D, Coronal section demonstrating the relationship of the pituitary to the optic chiasm and the pituitary stalk. E, Coronal section after gadolinium contrast demonstrating the close proximity of the pituitary to the internal carotid arteries.
C
5
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Section 1 Basic Science Table 1-6 Major Cell Types of the Anterior Pituitary Gland
Cell Type
Appearance on Light Microscopy
Cellular Frequency
Hormone Products
Somatotrophs
Acidophilic
50%
Growth hormone
Lactotrophs
Acidophilic
20%
Prolactin
Corticotrophs
Basophilic
20%
Corticotropin
Thyrotrophs
Basophilic
5%
Thyroid-stimulating hormone (TSH) and free α subunit
Gonadotrophs
Basophilic
5%
Follicle-stimulating hormone (FSH), luteinizing hormone (LH) and free α subunit
The sialic acid content of FSH, LH, TSH, and hCG varies, and these differences are largely responsible for variations in half-life of the glycoprotein hormones. The liver is the major site of clearance for gonadotropins. Sialic acid prevents hepatic clearance; thus, the greater the sialic acid content, the longer the half-life.41 hCG, with 20 sialic acid residues, has the longest half-life (about 24 hours), whereas LH (1 to 2 sialic acid residues) has the shortest half-life (20 to 30 minutes). Addition of sialic acid residues in urinary-derived commercially available gonadotropins (e.g., hMG) is responsible for their longer half-life (30 hours). In gonadotrophs of the anterior pituitary, GnRH signaling leads to transcription of the α and β subunits for both FSH and LH. The GnRH-dependent availability of the β subunits is the rate-limiting step in gonadotropin synthesis. Although both FSH and LH require GnRH stimulation, synthesis of the FSH β subunit also requires the presence of activin.42,43 Follicle-stimulating hormone plays a crucial role in follicle recruitment and selection of the dominant follicle. FSH has a trophic effect on granulosa cells in antral follicles, including the induction of aromatase activity, inhibin synthesis, and expression of LH receptors. A certain amount of FSH (the FSH threshold) is required to induce these changes in a given follicle. FSH must then remain above that threshold for folliculogenesis to continue. In the normal menstrual cycle serum concentrations of FSH begin to rise a few days before the onset of menstruation. FSH levels plateau in the midfollicular phase and decline in the late follicular phase in response to the rise in estrogen and inhibin B. This decline contributes to the dominance of selected follicles over others. FSH levels then peak briefly during the ovulatory gonadotropin surge, after which they decline to their nadir in the luteal phase. LH
6
LH is a glycoprotein with a molecular weight of 29,000 daltons. Like FSH, TSH, and hCG, it consists of both an α and β subunit. The α subunit is identical to the α subunit of FSH, TSH, and hCG. The β subunit of LH has 121 amino acids and 1 to 2 sialic acid residues. Luteinizing hormone is synthesized in gonadotrophs of the anterior pituitary gland. Because it contains fewer sialic acid residues than FSH, LH is rapidly cleared from the circulation by the liver and kidney. For this reason LH is rapidly biosynthesized,
and LH pulses occur at higher amplitude than those of FSH. It is believed that the pituitary content of LH is turned over 1 to 2 times per day. Serum LH levels begin to rise a few days before the onset of menstruation. They increase very gradually during the follicular phase. Unlike FSH, serum LH values rise in the late follicular phase, surpassing FSH values around cycle day 9 or 10. The LH surge at midcycle is followed by a steady decline to their nadir in the midluteal phase.
FSH and LH Receptors The actions of both LH and FSH are mediated by G protein receptors on the cell membrane. LH receptors are found exclusively on theca cells in the ovary. Stimulation of these receptors by increased cytochrome P450c17 enzyme activity (17-hydroxylase and 17,20-lyase) in theca cells, resulting in activation of both adenylate cyclase and cAMP-dependent protein kinases and leading to increased production of androstenedione and testosterone. In contrast, FSH receptors are found exclusively on granulosa cells in the ovary. FSH binds to receptors on the cell surface of granulosa cells in antral follicles. Like LH, FSH acts via the cAMP-dependent protein kinase pathway.44 In response to FSH the androgens produced as a result of LH stimulation are then aromatized to estrogens in granulosa cells.
Opioid Modulation of Pituitary Hormones Opioids (i.e., endogenous opiates) are natural occurring sedative narcotics produced in the brain whose structure and function are similar to opium. Opioids include enkephalins, endorphins, and dynorphins; they modulate every pituitary hormone by acting on the hypothalamus. An important action of opioids is to inhibit gonadotropin secretion by suppressing GnRH release.45 Opioid tone is an important regulator of menstrual cyclicity.46-49 Endorphins are at a nadir in the early follicular phase (menstruation) and gradually rise to peak levels in the luteal phase in response to the rise in estrogen and progesterone. It is believed that opioids mediate the negative feedback of ovarian steroids on gonadotropin release, particularly in the luteal phase.50 Endogenous opioids appear to play a central role in hypothalamic amenorrhea. Treatment of women suffering from this condition with an opioid receptor antagonist (e.g., naltrexone) results in the return to ovulatory menstrual patterns and even conception in some cases.51,52 Women with stress-related amenorrhea demonstrate increased hypothalamic corticotropinreleasing hormone and pituitary corticotropin, which manifests as hypercortisolism.53 The corticotropin precursor peptide, proopiomelanocortin, is also the precursor for endorphin synthesis. It is hypothesized that stress-related amenorrhea is the result of GnRH inhibition secondary to increased production of endogenous opioids. Opioids also rise during exercise (“runners’ high”), and this may contribute to hypothalamic amenorrhea in athletes.54,55
Ovarian Peptide Hormone Feedback on Gonadotropin Secretion The ovary secrets two polypeptide hormones that inhibit or stimulate FSH secretion by the anterior pituitary. Inhibin and activin act as opposing nonsteroidal gonadal hormones that
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Inhibin and activin are members of the transforming growth factor-β (TGF-β) superfamily of ligands, which includes müllerian inhibiting substance (MIS; see Chapter 2). Like the gonadotropins, inhibin and activin are comprised of two subunits. Inhibin is comprised of an α and β subunit and has been isolated in two forms containing different β subunits, Inhibin-A and Inhibin-B. Activin is comprised of two beta subunits identical to those found in inhibin. Inhibin is secreted by granulosa cells in response to FSH.56 However, mRNA for inhibin has also been found in pituitary gonadotrophs. Inhibin selectively inhibits FSH but not LH secretion.57 Thus, a negative feedback loop is created where FSH stimulates inhibin and in turn inhibin suppresses FSH. Inhibin B is predominantly secreted in the follicular phase of the menstrual cycle, whereas inhibin A is predominantly secreted in the luteal phase.58 Peak levels of inhibin B in the follicular phase are in the range of 50 to 100 pg/mL. Peak levels of inhibin A in the luteal phase are between 40 and 60 pg/mL. Activin is also secreted by granulosa cells. Activin augments the secretion of FSH by the pituitary by enhancing GnRH receptor formation. Activin is also required for synthesis of the FSH β subunit. In the ovary, activin augments FSH action and stimulates production of follistatin by a paracrine effect. These effects of activin are blocked by both inhibin and follistatin. With increased GnRH stimulation, activin is increasingly antagonized by inhibin and bound by follistatin.
Cell Type
Major Steroid Hormone Products
Theca cells
Androgens (androstenedione, DHEA, testosterone)*
Granulosa cells
Estrogens (estradiol, estrone)
Theca-lutein cells
Progestogens (progesterone, 17-hydroxyprogesterone)**
Granulosa-lutein cells
Estrogens (estradiol, estrone)
*Mostly via Δ5 pathway **Via Δ4 pathway
Cholesterol C27 P450scc 3βHSD Pregnenolone C21
Progesterone C21 P450c17
Δ4 pathway
Inhibin and Activin
Table 1-7 Site of Synthesis of Major Steroidogenic Products of the Ovary
17 hydroxypregnenolone C21
Δ5 pathway
regulate FSH synthesis and secretion by the pituitary. They also have paracrine effects within the ovary, where they modulate follicle growth and steroidogenesis. Follistatin is a binding protein that modulates the effects of activin but not inhibin.
17 hydroxyprogesterone C21 P450c17 3βHSD DHEA C19
Androstenedione C19 17βHSD
Aromatase
Follistatin
Follistatin is an activin-binding protein that sequesters activin. Follistatin is produced in the same tissues as activin, including the pituitary, and regulates activin’s local paracrine and autocrine actions. In the circulation, follistatin binds the majority of activin, thereby inhibiting FSH secretion. This suggests that activin’s primary actions are paracrine in nature. Follistatin does not bind inhibin, thus allowing it to act as a conventional endocrine hormone between the ovary and the pituitary in addition to its local ovarian effects.
OVARIAN STEROIDOGENESIS DURING THE MENSTRUAL CYCLE Ovarian steroidogenesis during the menstrual cycle occurs in granulosa and theca cells (Table 1-7 and Fig. 1-4). Before ovulation, theca cells are separated from granulosa cells in the same follicle by a basal membrane. Thus, granulosa cells of preovulatory follicles do not have a blood supply. However, at the time of the LH surge the preovulatory follicle undergoes luteinization with disappearance of the basal membrane and capillary invasion of the granulosa cells. Theca cells become theca-lutein cells, and granulosa cells become granulosa-lutein cells. If pregnancy does not occur, the lifespan of the corpus luteum is fixed at approximately 14 days. After 12to 14 days luteolysis and apoptosis are initiated. The corpus luteum involutes, and
Estrone C18 17βHSD
Testosterone C19
Aromatase
Estradiol C18 Figure 1-4 The Δ5 and Δ4 pathways. The rate-limiting step in steroidogenesis is the conversion of cholesterol to pregnenolone via side chain cleavage (P450scc). In the follicular phase pregnenolone is preferentially converted to androstenedione via the Δ5 pathway involving 17-hydroxypregnenolone and dehydroepiandrosterone (DHEA). In contrast, the corpus luteum preferentially converts pregnenolone to progesterone (Δ4 pathway) via 3β-hydroxysteroid dehydrogenase (3βHSD).
menstruation occurs. Ovarian steroidogenesis then shifts to a new cohort of follicles with their granulosa and theca cells.
Two-Cell Theory The two-cell, two-gonadotropin theory of ovarian steroidogenesis holds that follicular estrogen/androgen production is compartmentalized.59 Ovarian theca cells produce androgens in response to LH. These androgens may then be aromatized to estrogens in
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Section 1 Basic Science Table 1-8 Location Specificity of P450c17 and Aromatase Enzyme
Location
Function
P450c17
Theca cells only
Converts 21-carbon steroids (progesterone/pregnenolone) to 19-carbon steroids (androstenedione, DHEA)
Aromatase
Granulosa cells only
FSH
LH Cholesterol
Theca cell
Cholesterol
+
Converts 19-carbon steroids (androstenedione/testosterone) to 18-carbon steroids (estrone, estradiol)
Estrogens Estrogens are 18-carbon steroids that include estradiol (i.e., 17β-estradiol), estrone, and estriol. The most potent estrogen, estradiol, is predominantly secreted by the ovary. Estrone, which is one twelfth as potent as estradiol, is also secreted by the ovary. However, the principal source of estrone is from peripheral conversion from androstenedione. Estriol, which is one eightieth as potent as estradiol, is the principal estrogen formed by the placenta during pregnancy. Estriol is also formed by metabolism of estradiol and estrone by the liver and is the most abundant estrogen found in urine. Estrogen is largely bound to carrier proteins in serum. Approximately 60% of estradiol is bound to albumin, 38% is bound to sex hormone-binding globulin (SHBG), and 2% to 3% is free. It had previously been thought that only the free hormone was active and could enter cells, but recent evidence suggests that hormone transport and hormone availability may be more complex.62 Estrogen Receptors
8
There are two known estrogen receptors, ERα and ERβ. Both contain a steroid-binding domain, a DNA-binding domain, a hinge region, and a transcription-activation functional domain. The negative feedback of estradiol on FSH secretion is a direct effect of estradiol coupled to its receptor repressing transcription of the FSH β subunit.63 Negative feedback of estradiol on FSH may also be modulated by the estrogen-associated decline in pituitary expression of activin.64 Estrogens can enter any cell, but only cells with estrogen receptors will respond to its presence. When estrogens enter susceptible cells, estrogen associates with its receptor in the cell nucleus. This binding then activates the receptor. The DNAbinding domain of the estrogen–ER complex then associates with
P450scc Pregnenolone
LH-R
granulosa cells appropriately stimulated by FSH. FSH receptors are present only on granulosa cells, and early in the follicular phase LH receptors are present only on theca cells.60 The enzyme P450c17 (17-hydroxylase and 17,20-lyase) is only present in theca cells. Thus, only theca cells have the ability to convert 21-carbon steroids to 19-carbon steroids. In contrast, aromatase is only present in granulosa cells. Thus, in the ovary only granulosa cells have the ability to aromatize androgens to estrogens (Table 1-8 and Fig. 1-5). Supporting evidence for the two-cell theory includes the fact that women with hypogonadotropic hypogonadism may develop follicles in response to treatment with recombinant FSH, but do not significantly elevate androgen or estrogen levels unless LH is added to the stimulation regimen.61
StAR
+
P450c17
cAMP
17 hydroxypregnenolone
+
P450c17 DHEA 3βHSD
+
Androstenedione Basement membrane Granulosa cell cAMP
Androstenedione
+
Aromatase Estrone
FSH-R 17βHSD
Estradiol Figure 1-5 The two-cell theory and follicular phase steroidogenesis. Binding of luteinizing hormone (LH) to LH receptors on ovarian theca cells stimulates conversion of cholesterol to androstenedione. Binding of folliclestimulating hormone (FSH) to FSH receptors on granulosa cells then stimulates the aromatization of androgens to estrogens. StAR, steroidogenic acute regulatory protein; scc, side chain cleavage; HSD, hydroxysteroid dehydrogenase.
specific promoter sequences (DNA response elements) and activates gene transcription. Estrogen Metabolism
Serum concentrations of estradiol are less than 50 pg/mL in the early follicular phase. In response to follicle development estradiol levels rise, typically peaking at 200 to 300 pg/mL just before ovulation. Estradiol levels drop at the time of ovulation, then rise again, with a second peak in the midluteal phase reflecting estrogen secretion from the corpus luteum. The liver conjugates estrogens to form glucuronides and sulfates, about 80% of which are then excreted into the urine and 20% of which are excreted in the bile. In the liver, circulating estradiol is rapidly converted to estrone by 17β-hydroxysteroid dehydrogenase. Estrone may then be further metabolized in the
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Chapter 1 The Hypothalamic-Pituitary-Ovarian Axis and Control of the Menstrual Cycle liver to 16α-hydroxyestrone and then estriol. Estriol is then converted to estriol 3-sulfate-16-glucuronide before excretion by the kidney. Some 16α-hydroxyestrone may also be converted to catechol estrogens (i.e., 2-hydroxy or 4-hydroxyestrone). Biologically active catechol estrogens may then be converted to 2-methoxy and 4-methoxy compounds. Catechol estrogens are important because they have been implicated in carcinogenesis. Metabolism of catechol estrogens may generate oxygen free radicals.
Progesterone Progesterone, a 21-carbon steroid, is the principle secretory steroid of the corpus luteum. Progesterone is responsible for the induction of secretory changes that prepare estrogen-primed endometrium for implantation. If implantation occurs, continued progesterone production is necessary for maintenance of the pregnancy. The release of FSH and LH require the continuous pulsatile release of GnRH. The coordinated secretion of FSH and LH control follicle growth, ovulation, and maintenance of the corpus luteum. The release of FSH and LH is both positively and negatively influenced by estrogen and progesterone. Whether estrogen and progesterone stimulate or inhibit gonadotropin release depends on the quantity and duration of exposure to the steroid. At high concentrations progesterone inhibits both FSH and LH secretion by negative feedback on both the hypothalamus and pituitary.65 Progesterone also slows the GnRH pulse generator; hence the decline in GnRH pulse frequency in the luteal phase. However, at low concentrations, and only after previous exposure to estrogen, progesterone stimulates LH release.66 Progesterone Receptors
Progesterone receptors are similar to estrogen receptors in that they contain a steroid-binding domain, a DNA-binding domain, a hinge region, and a transcription-activation functional domain. There are two progesterone receptors, A and B. Receptor B is the positive regulator of progesterone-responsive genes. Binding of progesterone to progesterone receptor A inhibits activity of receptor B. Progesterone causes a depletion of estrogen receptors. This is the mechanism by which progestins protect against endometrial hyperplasia.
Progesterone is rapidly cleared from the circulation by the liver. The liver converts progesterone to pregnanediol. Pregnanediol is then conjugated to glucuronic acid, and pregnanediol glucuronide is excreted in the urine. Measurement of urinary pregnanediol glucuronide can be used as an index of progesterone production.
Androgens Ovarian theca cells secrete a variety of androgens (i.e., 19-carbon steroids), including androstenedione, testosterone, and dehydroepiandrosterone (DHEA). Androstenedione is the principal androgen secreted by ovarian theca cells. Theca cells also possess the enzyme 17β-hydroxysteroid dehydrogenase, which may convert androstenedione to testosterone. In premenopausal women, at least 60% of circulating testosterone is derived from the ovary, by either this conversion or direct secretion. Androstenedione and testosterone can then be aromatized to estrogens in granulosa cells under the influence of FSH. Androstenedione can also be converted to estrone or testosterone in peripheral tissues. Unlike testosterone and dihydrotestosterone, androstenedione does not have high affinity for the androgen receptor. Side chain cleavage of cholesterol to pregnenolone is the starting point and rate-limiting step in steroidogenesis. In the ovary cholesterol side chain cleavage is regulated by LH. Lowdensity lipoprotein (LDL) cholesterol is the principal source of cholesterol for steroidogenesis in the human ovary.67 Increased cAMP production due to LH stimulation of adenylate cyclase increases transcription of LDL receptor mRNA and LDL uptake. cAMP-activated steroidogenic acute regulatory protein then increases the intracellular transport of cholesterol to the inner mitochondrial membrane, where side chain cleavage occurs.68 In the preovulatory follicle the preferred pathway for androgen/ estrogen synthesis involves conversion of pregnenolone to 17-hydroxypregnenolone, the so-called Δ5 pathway (see Fig. 1-4). Ovarian theca cells have the enzymatic capability to convert pregnenolone to androgens, but lack the ability to aromatize androstenedione or testosterone into estrogens. Only granulosa cells, under the influence of FSH, can aromatize androgens to estrogens. In contrast to the preovulatory follicle, the corpus luteum prefers the Δ4 pathway, the initial conversion of pregnenolone to progesterone. Androgen Receptors
Progesterone Metabolism
Throughout the follicular phase serum progesterone concentrations are less than 1 ng/mL. Much of this progesterone is believed to result from adrenal production of pregnenolone and progesterone as a by-product of cortisol and aldosterone synthesis. In the late follicular phase progesterone levels begin to rise as the ovary starts to contribute to progesterone production. The rise in progesterone accelerates markedly after ovulation, and progesterone levels reach 10 to 20 ng/mL in the midluteal phase. If pregnancy does not occur, progesterone levels fall in the late luteal phase and return to levels below 1 ng/mL just before the onset of menstruation. In the circulation, approximately 80% of progesterone is bound to albumin. Another 18% is bound to corticosteroidbinding globulin. About 2.5% is freely circulating, and only about 0.5% is bound to SHBG.
The androgen receptor is similar to the estrogen receptor. It activates target gene expression via a similar sequence of ligand binding, nuclear translocation, DNA binding, and complex formation with coregulators and general transcription factors. Although the androgen receptor is known to play a central role in the development of male sex organs and secondary sexual characteristics, its physiologic roles in female reproduction remain unclear. Recent studies in androgen-deficient animals suggest that androgen receptors play an important role in granulosa cell development.69 These animals also exhibit reduced fertility with defective folliculogenesis, reduced corpus luteum formation, and reduced uterine response to gonadotropins. Androgen Metabolism
Androstenedione is produced in equal amounts by the ovaries and adrenal glands. The serum concentrations mirror estradiol
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Section 1 Basic Science levels and range from 0.5 to 3 ng/mL. Androstenedione levels increase in the mid- to late follicular phase and are maximal just before the LH surge. They decline at the time of ovulation, reach a second peak in the midluteal phase, and are lowest around the time of menstruation. Serum testosterone concentrations, in contrast, vary to a much lesser extent during the menstrual cycle and exhibit only a transient periovulatory increase. Testosterone concentrations range from 1.5 to 60 ng/dL.
CONTROL OF THE MENSTRUAL CYCLE Normal menstrual cycles, termed eumenorrhea, normally range in length between 24 to 35 days, with menstrual bleeding lasting 3 to 7 days. The average amount of blood loss is approximately 30 mL.70 Heavy, prolonged, or irregular menses are referred to as abnormal uterine bleeding and are considered in length in Chapter 21. Normal menstrual cycles result from a relatively precise interaction of the hypothalamus, pituitary, and ovaries. Under the influence of pituitary gonadotropins, the ovary undergoes cyclic changes providing for the development and release of a mature oocyte and production of ovarian hormones that prepare the endometrial lining for implantation. LH stimulates androgen production in theca cells; FSH promotes follicle development and aromatization of androgens to estrogens in granulosa cells (see Fig. 1-5). In turn, estrogens lead to proliferation of the endometrial lining and the induction of endometrial receptors for both estrogen and progesterone.71 To understand the menstrual cycle it is helpful to divide it into four phases: the follicular phase, the ovulatory phase, the luteal phase, and the luteal–follicular transition. We concentrate on changes in pituitary and ovarian hormones and the effects that these hormones have on the hypothalamus, pituitary, and ovary.
Follicular Phase The purpose of the follicular phase is to develop a single mature follicle to release a mature oocyte at ovulation. The presence of sufficient FSH also leads to expression of LH receptors on mature granulosa cells of preovulatory follicles. Thus, in the late follicular phase LH can sustain follicular endocrine activity, even in the absence of FSH.72 The follicular phase is variable in duration, but the other three phases are relatively constant, averaging 14 ± 2 days.
granulosa cells can cause upregulation or downregulation of granulosa cell FSH receptors.75 Without functional FSH follicle growth and ovarian estrogen production cannot occur.76 The steady decline in FSH beginning in the midfollicular phase serves to inhibit development of all but the dominant follicle. The dominant follicle remains dependent on FSH and must complete its development in spite of declining FSH levels. Because it has the largest cohort of granulosa cells, it has the largest cohort of FSH receptors and thus is able to grow in the face of insufficient FSH for smaller follicles. Luteinizing hormone levels are stable in the first half of the follicular phase. However, in the second half LH levels rise in response to positive feedback from increasing estrogen. Ovarian Hormones
Estradiol levels rise as the dominant follicle emerges. FSH and estrogen synergistically exert a mitogenic effect on granulosa cells, stimulating their proliferation. This in turn increases the FSH receptor content of the follicle, enhancing the ability of the follicle to respond to FSH and produce estrogen. Curiously, not every granulosa cell must express FSH receptors to respond to the gonadotropin signal. Gap junctions between cells allow cells with receptors to transmit protein kinase activation to their neighbors.77
LH FSH
A Estradiol Inhibin B Inhibin A
B
GnRH
Progesterone
Throughout most of the follicular phase GnRH pulses occur every 60 to 90 minutes. Just before the onset of the LH surge both GnRH pulse frequency and amplitude increase. Gonadotropins
10
FSH levels rise in the early follicular phase due to the lack of negative inhibition from estradiol and inhibin (Fig. 1-6). FSH stimulates follicle growth and estrogen production.73 Through binding of FSH to its receptor, granulosa cells in developing follicles attain the ability to aromatize androstenedione to estrone and testosterone to estradiol. Importantly, receptors for FSH are not detected on granulosa cells until the preantral stage.74 Moreover, both in vitro and in vivo administration of FSH to
2
C
4
6
8
10
12
14 16 18 Cycle day
20
22
24
26
28
30
Figure 1-6 Hormone fluctuations during the menstrual cycle. A, Mean values of follicle-stimulating hormone and luteinizing hormone throughout the cycle. B, Mean values of estradiol and inhibin. C, Mean values of progesterone during the menstrual cycle.
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Chapter 1 The Hypothalamic-Pituitary-Ovarian Axis and Control of the Menstrual Cycle Within the follicular fluid of follicles greater than 8 mm in diameter, the concentration of FSH, estradiol, and progesterone are all extremely high. Within smaller antral follicles, androgens predominate in the follicular fluid. The role of androgens in the follicle is dose-dependent. At low levels androgens provide a substrate for aromatization. However, at higher levels androgens are converted in granulosa cells by 5α-reductase to more active forms such as dihydrotestosterone (DHT) that cannot be aromatized to estrogens.78,79 Granulosa cells have androgen receptors.80 Activation of granulosa cell androgen receptors inhibits aromatase activity and also inhibits FSH induction of granulosa LH receptors.81 Follicles exposed to excessive androgens eventually become atretic.82,83 In contrast, follicles with the highest estrogen-to-androgen ratios and the highest estrogen concentrations are most likely to contain a competent oocyte.84 Rising estradiol levels have a dual role for the follicle. Within the follicle, estradiol promotes granulosa cell growth, aromatization of androgens to estrogens, and, in combination with FSH, induction of development of LH receptors on granulosa cells. However, outside the follicle rising serum estradiol levels have an inhibitory effect on FSH secretion. The resulting decline in FSH levels in the mid- to late follicular phase limits aromatase activity in smaller follicles, leading to higher androgen levels and follicular atresia. Indeed, a reduction in granulosa cell expression of FSH receptors is one of the first signs of follicular atresia. Inhibin B levels begin to rise almost immediately after the rise in FSH levels. By the midfollicular phase the rise in estradiol and inhibin B levels causes FSH levels to decline. Inhibin B levels peak approximately 4 days after the FSH peak.47 In the late follicular phase inhibin B levels fall, mirroring the decline in FSH levels. Progesterone and inhibin A levels are low throughout most of the follicular phase, but both begin to rise in the days immediately preceding ovulation. The rise in progesterone in the late follicular phase mirrors the rise in LH.
Ovulatory Phase The ovulatory phase begins with the midcycle LH surge, which disrupts contacts between granulosa cells and the cumulus oophorus (specialized granulosa cells surrounding the oocyte), causing the oocyte to detach from the follicle wall. The LH surge also induces the resumption of meiosis within the oocyte and release of the oocyte–cumulus complex from the follicle (ovulation). GnRH
GnRH plays a supporting role for the midcycle gonadotropin surge, but it does not trigger the surge.85 There is no change in GnRH pulse frequency during the midcycle gonadotropin surge.86 Rather, ovarian steroid feedback to the primed anterior pituitary triggers the LH surge.87 Whereas estrogen inhibits the secretion of pituitary gonadotropins, it facilitates their synthesis and storage. Estrogen also increases the expression of GnRH receptors.88,89 Thus, in the mid- to late follicular phase each pulse of GnRH is met with a greater gonadotropin response.90,91 When the estradiol level in the circulation meets a critical level for a sufficiently long period of time, the inhibitory action of estradiol on LH secretion changes to a stimulatory one. The LH surge is accompanied by a surge of GnRH in both portal and peripheral blood.92 However, as demonstrated by women with hypo-
gonadotropic hypogonadism treated with a pulsatile GnRH pump, ovulation and pregnancy may occur in the absence of any change in GnRH pulse frequency or amplitude.93 Moreover, the LH surge ends before there is a decline in the GnRH signal.94 Gonadotropins
Both FSH and LH levels peak just before ovulation. The initiation of the gonadotropin surge is dependent on attaining serum estradiol levels of at least 200 pg/mL for at least 2 days.95 In natural cycles this level of estradiol is typically not attained until the dominant follicle reaches a mean diameter of 15 mm.96 During the gonadotropin surge serum LH levels increase tenfold over a period of 2 to 3 days, while FSH levels increase fourfold. Within the dominant follicle the LH surge induces detachment of the oocyte–cumulus complex from the follicle wall. The release of the oocyte–cumulus complex from its follicular wall attachments is accompanied by the resumption of meiosis and release of the first polar body. The LH surge also induces luteinization of the periovulatory follicle. Luteinization refers to functional and morphologic changes within the theca–granulosa cell complex associated with accumulation of a yellow pigment called lutein. The function of the FSH surge is less clearly known, but it is believed to ensure an adequate number of LH receptors on the granulosa layer and to increase production of plasminogen activator, thus increasing the concentration of the proteolytic enzyme plasmin. Ovulation typically occurs from mature follicles 34 to 36 hours after the onset of the LH surge.97 The peak of LH and FSH occurs 10 to 12 hours before ovulation.98 The LH surge usually lasts 48 to 50 hours and must be maintained for at least 14 hours for full maturation of the oocyte to occur.99 The mechanism that turns off the LH surge is unknown. It may simply reflect the depletion in pituitary LH content. Ovarian Hormones
Just prior to ovulation the follicle becomes vascularized.100 Angiogenesis is mediated by LH and a variety of other factors, including vascular endothelial growth factor.101-103 Prostaglandins reach peak levels in the follicular fluid.104 Proteolytic enzymes digest collagen in the follicular wall, resulting in distensibility and thinning just before ovulation.105 Progesterone rises in the follicular fluid. FSH, LH, and progesterone all serve to increase the activity of proteolytic enzymes. There is a rapid increase in follicular fluid volume, but due to increased elasticity there is little to no change in intrafollicular pressure. Finally, a protrusion (stigma) appears on the follicular wall, and it is at this site that ovulation ultimately occurs. Interestingly, spontaneous lueteinization occurs in the absence of LH when granulosa cells are removed from follicles and cultured in vitro. Similarly, cumulus-enclosed oocytes removed from developing follicles before the LH surge will spontaneously resume meiosis.106,107 These findings have led to speculation that substances functioning as oocyte maturation inhibitors or luteinization inhibitors must exist within each follicle. Further support for this hypothesis lies in the fact that cumulus cells lack LH receptors. Estradiol levels fall beginning with the onset of the LH surge. Progesterone and inhibin A levels continue to rise at the time of ovulation. Inhibin B levels surge at the time of ovulation. Luteinization of the follicle begins.
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Section 1 Basic Science Luteal Phase The luteal phase is the time when the ovary secrets progesterone, resulting in endometrial receptivity for embryo implantation. LH receptors on granulosa cells result in luteinization, driving the postovulatory follicle to become a corpus luteum. Granulosa cells become granulosa-lutein cells with their own blood supply and begin secretion of both estrogen and progesterone. Release of large amounts of progesterone from the corpus luteum results in secretory endometrial changes and the final development of endometrial receptivity. GnRH and Gonadotropins
GnRH pulse frequency declines but pulse amplitude increases in the luteal phase. Changes in GnRH pulse frequency correlate with the duration of exposure to progesterone; changes in pulse amplitude correlate with progesterone levels.17 Luteinizing hormone and FSH levels reach a nadir during the luteal phase in response to the elevation in estrogen, progesterone, and inhibin A. Nevertheless, function of the corpus luteum is dependent on continued low-level pituitary gonadotropin secretion throughout the luteal phase.108 LH pulses stimulate pulses of progesterone secretion from the corpus luteum.17,109 Moreover, reducing LH pulse frequency and amplitude with a GnRH agonist in the luteal phase shortens the luteal phase itself.110 Ovarian Hormones
After ovulation granulosa and theca cells of the dominant follicle are luteinized. Luteinization involves both chemical and morphologic changes. Granulosa and theca cells hypertrophy and increase steroidogenesis. Moreover, breakdown of the basal membrane that previously separated granulosa and theca cells leads to capillary invasion around granulosa-lutein cells. Granulosa-lutein cells can now make progesterone directly from LDL via side chain cleavage and 3β-hydroxysteroid dehydrogenase. Levels of mRNA for side chain cleavage and 3βhydroxysteroid dehydrogenase are maximal at the time of ovulation and in the early luteal phase.111 The induction of LDL receptor expression in granulosa cells occurs in response to the LH surge and is an early feature of luteinization.112 Progesterone secretion correlates with the number of LH receptors and adenylate cyclase activity.113 Progesterone levels peak during the midluteal phase. Granulosa-lutein cells cannot make estrogens directly from cholesterol because they lack the enzyme P450c17. However, granulosa-lutein cells continue to be able to aromatize thecalutein produced androgens to estrogens, and estrogen levels remain high throughout most of the luteal phase. In granulosa-lutein cells inhibin production switches from inhibin B to inhibin A. Thus inhibin B levels decline to their nadir during the luteal phase, whereas inhibin A levels reach their peak. Secretion of inhibin A by granulosa-lutein cells is controlled by LH.114 Inhibin A, like inhibin B, suppresses FSH levels.115
Luteal–Follicular Transition
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As the luteal phase continues, progesterone inhibits LH release via a negative feedback loop on the anterior pituitary. During the luteal–follicular transition, subsequent decline in LH causes the
corpus luteum to involute unless the corpus luteum is rescued by production of hCG from an implanting embryo. Involution of the corpus luteum leads to a fall in both estrogen and progesterone production. The endometrium can no longer be maintained and menstruation occurs. The fall of estrogen production then reactivates FSH secretion, initiating a new cycle of follicular development with estrogen secretion and renewed proliferation of the endometrial lining. GnRH
A progressive and rapid increase in GnRH pulse frequency occurs during the luteal–follicular transition. GnRH pulse frequency, as estimated by LH pulse frequency, increases from 3 pulses per 24 hours (midluteal phase) to 14 pulses per 24 hours.18 Gonadotropins
FSH and LH levels rise from their nadir due to the decline in negative feedback from estradiol and inhibin and the rise in activin.116 The rise in FSH initiates recruitment of gonadotropinresponsive follicles for the next menstrual cycle. This recruitment of antral follicles actually begins at least 2 days before the onset of menstrual bleeding. In fact, an increase in FSH bioactivity can be measured back to the midluteal phase.117 During the luteal–follicular transition both inhibin A and B levels are at a nadir.118 In contrast, activin levels begin to increase in the late luteal phase and peak at the time of menstruation.119 Activin plays an important role as gonadotropin responses to GnRH require the presence of activin.43 Ovarian Hormones
In the absence of pregnancy corpus luteum function declines approximately 10 days after ovulation. The exact mechanisms for luteolysis are unclear. Luteolysis involves apoptosis and expression of matrix metalloproteinases.120,121 Luteolysis may also be mediated by nitric oxide.122 Nitric oxide induces apoptosis in the human corpus luteum.123 One of the final signs of luteolysis is ovarian production of prostaglandin F2α, which inhibits luteal steroidogenesis. Thus, unless the corpus luteum is rescued by the hCG of pregnancy, estrogen, progesterone, and inhibin levels fall as the luteal–follicular transition occurs.
PEARLS ●
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GnRH-secreting neurons are found predominantly in the arcuate nucleus of the hypothalamus. GnRH is released into the portal circulation at the median eminence in a pulsatile fashion and binds to cell membrane receptors in the anterior pituitary. GnRH pulse frequency and amplitude vary during the menstrual cycle. The follicular phase is characterized by highfrequency (q60–90 minutes), low-amplitude pulses; the luteal phase is characterized by lower-frequency (q2–4 hours), higher-amplitude pulses. The activity of GnRH-releasing neurons is modified by a variety of factors, including neurotransmitters, glycoprotein hormones, and steroid hormones. GnRH has an extremely short half-life (2 to 4 minutes). GnRH agonists and antagonists are characterized by modifications to the native GnRH decapeptide structure that extend its half-life.
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The pituitary gland lies in the sella turcica and is connected to the hypothalamus via the pituitary stalk. The blood supply to the pituitary gland comes from the internal carotid artery. Specialized cells within the anterior pituitary (gonadotrophs) secrete FSH and LH in response to GnRH. Gonadotrophs comprise only 5% of all the cells in the anterior pituitary gland. FSH and LH are glycoproteins that share the same α subunit. The half-life of LH (20 to 30 minutes) is much shorter than that of FSH (1 to 4 hours), and LH pulse frequency/amplitude correlates closely with GnRH pulse frequency and amplitude. FSH and LH bind to cell membrane receptors that activate adenylate cyclase, thus raising intracellular cyclic AMP. FSH plays a crucial role in folliculogenesis, as well as inducing aromatization of androgens to estrogens. LH plays a crucial role in ovulation and steroidogenesis. Certain steroidogenic enzymes are specific to certain ovarian cell types. Only theca cells express P450c17, the enzyme
●
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that allows conversion of progestins (21-carbon steroids) to androgens (19-carbon steroids). In turn, only granulosa cells, stimulated by FSH, have the ability to aromatize androgens to estrogens (18-carbon steroids). Granulosa cells of preovulatory follicles do not have a direct blood supply; they are separated from theca cells by a basal membrane. In contrast, almost immediately after ovulation capillaries invade the granulosa layer. In theca cells of the preovulatory follicle pregnenolone is preferentially converted to 17-hydroxypregnenolone (Δ5 pathway) on the way to synthesis of androstenedione. In the corpus luteum pregnenolone is preferentially converted to progesterone (Δ4 pathway). Progesterone, 17-hydroxyprogesterone, and inhibin A levels all peak in the luteal phase. The lifespan of the corpus luteum is fixed at approximately 14 days. If the corpus luteum is not rescued by hCG, luteolysis and apoptosis are initiated.
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3′,5′-monophosphate: One molecule, two messages. Clin Endocrinol (Oxf) 37:51–58, 1992. Oktay K, Briggs D, Gosden RG: Ontogeny of follicle-stimulating hormone receptor gene expression in isolated human ovarian follicles. J Clin Endocrinol Metab 82:3748–3751, 1997. LaPolt PS, Tilly JL, Aihara T, et al: Gonadotropin-induced up- and down-regulation of ovarian follicle-stimulating hormone (FSH) receptor gene expression in immature rats: Effects of pregnant mare’s serum gonadotropin, human chorionic gonadotropin, and recombinant FSH. Endocrinology 130:1289–1295, 1992. Matthews CH, Borgato S, Beck-Peccoz P, et al: Primary amenorrhoea and infertility due to a mutation in the beta-subunit of folliclestimulating hormone. Nat Genet 5:83–86, 1993. Fletcher WH, Greenan JR: Receptor mediated action without receptor occupancy. Endocrinology 116:1660–1662, 1985. McNatty KP, Makris A, Reinhold VN, et al: Metabolism of androstenedione by human ovarian tissues in vitro with particular reference to reductase and aromatase activity. Steroids 34:429–443, 1979. Hillier SG, van den Boogaard AM, Reichert LE Jr, van Hall EV: Intraovarian sex steroid hormone interactions and the regulation of follicular maturation: Aromatization of androgens by human granulosa cells in vitro. J Clin Endocrinol Metab 50:640–647, 1980. Hild-Petito S, West NB, Brenner RM, Stouffer RL: Localization of androgen receptor in the follicle and corpus luteum of the primate ovary during the menstrual cycle. Biol Reprod 44:561–568, 1991. Jia XC, Kessel B, Welsh TH Jr, Hsueh AJ: Androgen inhibition of follicle-stimulating hormone-stimulated luteinizing hormone receptor formation in cultured rat granulosa cells. Endocrinology 117:13–22, 1985. Erickson GF, Magoffin DA, Dyer CA, Hofeditz C: The ovarian androgen producing cells: A review of structure/function relationships. Endocr Rev 6:371–399, 1985. Chabab A, Hedon B, Arnal F, et al: Follicular steroids in relation to oocyte development and human ovarian stimulation protocols. Hum Reprod 1:449–454, 1986. Andersen CY: Characteristics of human follicular fluid associated with successful conception after in vitro fertilization. J Clin Endocrinol Metab 77:1227–1234, 1993. Knobil E, Plant TM, Wildt L, et al: Control of the rhesus monkey menstrual cycle: Permissive role of hypothalamic gonadotropinreleasing hormone. Science 207:1371–1373, 1980. Adams JM, Taylor AE, Schoenfeld DA, et al: The midcycle gonadotropin surge in normal women occurs in the face of an unchanging gonadotropin-releasing hormone pulse frequency. J Clin Endocrinol Metab 79:858–864, 1994. Nakai Y, Plant TM, Hess DL, et al: On the sites of the negative and positive feedback actions of estradiol in the control of gonadotropin secretion in the rhesus monkey. Endocrinology 102:1008–1014, 1978. Gregg DW, Nett TM: Direct effects of estradiol-17 β on the number of gonadotropin-releasing hormone receptors in the ovine pituitary. Biol Reprod 40:288–293, 1989. Bauer-Dantoin AC, Weiss J, Jameson JL: Roles of estrogen, progesterone, and gonadotropin-releasing hormone (GnRH) in the control of pituitary GnRH receptor gene expression at the time of the preovulatory gonadotropin surges. Endocrinology 136:1014–1019, 1995. Adams TE, Norman RL, Spies HG: Gonadotropin-releasing hormone receptor binding and pituitary responsiveness in estradiol-primed monkeys. Science 213:1388–1390, 1981. Menon M, Peegel H, Katta V: Estradiol potentiation of gonadotropinreleasing hormone responsiveness in the anterior pituitary is mediated by an increase in gonadotropin-releasing hormone receptors. Am J Obstet Gynecol 151:534–540, 1985. Xia L, Van Vugt D, Alston EJ, et al: A surge of gonadotropin-releasing hormone accompanies the estradiol-induced gonadotropin surge in the rhesus monkey. Endocrinology 131:2812–2820, 1992. Leyendecker G, Wildt L, Hansmann M: Pregnancies following chronic intermittent (pulsatile) administration of Gn-RH by means of a portable pump (“Zyklomat”)—a new approach to the treatment of infertility in hypothalamic amenorrhea. J Clin Endocrinol Metab 51:1214–1216, 1980.
94. Caraty A, Antoine C, Delaleu B, et al: Nature and bioactivity of gonadotropin-releasing hormone (GnRH) secreted during the GnRH surge. Endocrinology 136:3452–3460, 1995. 95. Young JR, Jaffe RB: Strength–duration characteristics of estrogen effects on gonadotropin response to gonadotropin-releasing hormone in women. II. Effects of varying concentrations of estradiol. J Clin Endocrinol Metab 42:432–442, 1976. 96. Cahill DJ, Wardle PG, Harlow CR, Hull MG: Onset of the preovulatory luteinizing hormone surge: Diurnal timing and critical follicular prerequisites. Fertil Steril 70:56–59, 1998. 97. Hoff JD, Quigley ME, Yen SS: Hormonal dynamics at midcycle: A reevaluation. J Clin Endocrinol Metab 57:792–796, 1983. 98. Pauerstein CJ, Eddy CA, Croxatto HD, et al: Temporal relationships of estrogen, progesterone, and luteinizing hormone levels to ovulation in women and infrahuman primates. Am J Obstet Gynecol 130:876–886, 1978. 99. Zelinski-Wooten MB, Hutchison JS, Chandrasekher YA, et al: Administration of human luteinizing hormone (hLH) to macaques after follicular development: Further titration of LH surge requirements for ovulatory changes in primate follicles. J Clin Endocrinol Metab 75:502–507, 1992. 100. McClure N, Macpherson AM, Healy DL, et al: An immunohistochemical study of the vascularization of the human graafian follicle. Hum Reprod 9:1401–1405, 1994. 101. Wulff C, Wilson H, Wiegand SJ, et al: Prevention of thecal angiogenesis, antral follicular growth, and ovulation in the primate by treatment with vascular endothelial growth factor Trap R1R2. Endocrinology 143:2797–2807, 2002. 102. Wulff C, Wilson H, Largue P, et al: Angiogenesis in the human corpus luteum: Localization and changes in angiopoietins, tie-2, and vascular endothelial growth factor messenger ribonucleic acid. J Clin Endocrinol Metab 85:4302–4309, 2000. 103. Dickson SE, Fraser HM: Inhibition of early luteal angiogenesis by gonadotropin-releasing hormone antagonist treatment in the primate. J Clin Endocrinol Metab 85:2339–2344, 2000. 104. Lumsden MA, Kelly RW, Templeton AA, et al: Changes in the concentration of prostaglandins in preovulatory human follicles after administration of hCG. J Reprod Fertil 77:119–124, 1986. 105. Yoshimura Y, Santulli R, Atlas SJ, et al: The effects of proteolytic enzymes on in vitro ovulation in the rabbit. Am J Obstet Gynecol 157:468–475, 1987. 106. Edwards RG: Maturation in vitro of human ovarian oocytes. Lancet 2(7419):926–929, 1965. 107. Edwards RG: Maturation in vitro of mouse, sheep, cow, pig, rhesus monkey and human ovarian oocytes. Nature 208:349–351, 1965. 108. Hutchison JS, Zeleznik AJ: The rhesus monkey corpus luteum is dependent on pituitary gonadotropin secretion throughout the luteal phase of the menstrual cycle. Endocrinology 115:1780–1786, 1984. 109. Filicori M, Butler JP, Crowley WF Jr: Neuroendocrine regulation of the corpus luteum in the human. Evidence for pulsatile progesterone secretion. J Clin Invest 73:1638–1647, 1984. 110. Sheehan KL, Casper RF, Yen SS: Luteal phase defects induced by an agonist of luteinizing hormone-releasing factor: A model for fertility control. Science 215:170–172, 1982. 111. Bassett SG, Little-Ihrig LL, Mason JI, Zeleznik AJ: Expression of messenger ribonucleic acids that encode for 3 β-hydroxysteroid dehydrogenase and cholesterol side-chain cleavage enzyme throughout the luteal phase of the macaque menstrual cycle. J Clin Endocrinol Metab 72:362–326, 1991. 112. Brannian JD, Shiigi SM, Stouffer RL: Gonadotropin surge increases fluorescent-tagged low-density lipoprotein uptake by macaque granulosa cells from preovulatory follicles. Biol Reprod 47:355–360, 1992. 113. Rojas FJ, Moretti-Rojas I, Balmaceda JP, Asch RH: Regulation of gonadotropin-stimulable adenylyl cyclase of the primate corpus luteum. J Steroid Biochem 32:175–182, 1989. 114. McLachlan RI, Cohen NL, Vale WW, et al: The importance of luteinizing hormone in the control of inhibin and progesterone secretion by the human corpus luteum. J Clin Endocrinol Metab 68:1078–1085, 1989.
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Section 1 Basic Science 115. Molskness TA, Woodruff TK, Hess DL, et al: Recombinant human inhibin-A administered early in the menstrual cycle alters concurrent pituitary and follicular, plus subsequent luteal, function in rhesus monkeys. J Clin Endocrinol Metab 81:4002–4006, 1996. 116. le Nestour E, Marraoui J, Lahlou N, et al: Role of estradiol in the rise in follicle-stimulating hormone levels during the luteal-follicular transition. J Clin Endocrinol Metab 77:439–442, 1993. 117. Christin-Maitre S, Taylor AE, Khoury RH, et al: Homologous in vitro bioassay for follicle-stimulating hormone (FSH) reveals increased FSH biological signal during the mid- to late luteal phase of the human menstrual cycle. J Clin Endocrinol Metab 81:2080–2088, 1996. 118. Roseff SJ, Bangah ML, Kettel LM, et al: Dynamic changes in circulating inhibin levels during the luteal-follicular transition of the human menstrual cycle. J Clin Endocrinol Metab 69:1033–1039, 1989.
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119. Muttukrishna S, Fowler PA, George L, et al: Changes in peripheral serum levels of total activin A during the human menstrual cycle and pregnancy. J Clin Endocrinol Metab 81:3328–3334, 1996. 120. Shikone T, Yamoto M, Kokawa K, et al: Apoptosis of human corpora lutea during cyclic luteal regression and early pregnancy. J Clin Endocrinol Metab 81:2376–2380, 1996. 121. Young KA, Hennebold JD, Stouffer RL: Dynamic expression of mRNAs and proteins for matrix metalloproteinases and their tissue inhibitors in the primate corpus luteum during the menstrual cycle. Mol Hum Reprod 8:833–840, 2002. 122. Friden BE, Runesson E, Hahlin M, Brannstrom M: Evidence for nitric oxide acting as a luteolytic factor in the human corpus luteum. Mol Hum Reprod 6:397–403, 2000. 123. Vega M, Urrutia L, Iniguez G, et al: Nitric oxide induces apoptosis in the human corpus luteum in vitro. Mol Hum Reprod 6:681–687, 2000.
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2
Ovarian Hormones: Structure, Biosynthesis, Function, Mechanism of Action, and Laboratory Diagnosis Manjula K. Gupta and SuYnn Chia
INTRODUCTION The main function of the ovaries, maturation and release of oocytes, is accomplished via the production of several steroidal and nonsteroidal hormones that locally modulate a series of complex events. Peripherally, these hormones act on various target organs, including the uterus, vagina, fallopian tubes, mammary glands, adipose tissue, bones, kidneys, and liver, leading to the female phenotype. The secretion of the ovarian hormones in turn is precisely regulated by the hypothalamic-pituitary axis. The complex interactions and regulations of the hypothalamic, pituitary, and ovarian hormones are collectively responsible for the regular and predictable ovulatory menstrual cycle and fertility in females.
STEROIDOGENESIS AND STEROID HORMONES OF THE OVARY The ovary contains multiple distinctive steroid-producing cells, including stromal cells, theca cells, granulosa cells, and luteinized granulosa cells. Each cell type contains all the enzymes necessary for synthesis of androgens, estrogens, and progesterone. However, the types of hormones produced vary according to the cell type and the expression of steroidogenic enzymes. Other factors that influence which steroid hormone is synthesized in a given cell include the level and expression of gonadotropin and the availability of low-density lipoprotein (LDL) cholesterol. (As discussed below, steroid hormone synthesis occurs via one of two pathways: the Δ5[3β-hydroxysteroid] pathway or the Δ4[3 ketone] pathway.)
Steroidogenesis
The Ovary as an Endocrine Organ A single ovarian follicle is regarded as the basic endocrine/ reproductive unit of the ovary. It is composed of one germ cell that is surrounded by a cluster of endocrine cells, which are organized in two layers separated by a basal membrane. The inner layer surrounding the oocyte is composed of granulosa cells, and the outer layer is composed of thecal cells. These two cell types provide the basic machinery that is responsible for producing ovarian hormones. These cells are also differentially regulated by the gonadotropins (i.e., luteinizing hormone [LH] and follicle-stimulating hormone [FSH]) and produce distinctly different steroid hormones. The two-cell theory describes the sequence of events that occurs during ovarian follicular growth and steroidogenesis. According to this theory, LH primarily stimulates thecal cells to produce androstenedione and testosterone, both 19-carbon steroids. In contrast, FSH primarily stimulates granulosa cells to aromatize these 19-carbon steroids into estrogens.1,2 The ovarian production of steroid hormones is regulated both within the ovary, by paracrine (intercellular) and autocrine (intracellular) mechanisms, and by endocrine regulation of FSH secretion by the pituitary. Central to this regulation are several nonsteroidal hormones and factors produced by the ovary.3 This chapter focuses on these aspects of the ovary and discusses the biochemistry, biosynthesis, regulation, and actions of both steroidal and peptide ovarian hormones.
The ovary, like the adrenal gland, produces all three classes of steroid hormones from cholesterol—estrogens, progesterone, and androgens. In contrast to the adrenal gland, the ovary cannot produce glucocorticoids or mineralocorticoids because it lacks the enzymes 21-hydroxylase and 11β-hydroxylase. Steroid hormone formation in the steroid-producing endocrine glands follows the same fundamental pathway and mainly relies on exogenous (or plasma) cholesterol, with the exception of the liver and intestinal mucosa, which are capable of synthesizing cholesterol endogenously from acetyl-coA. The primary source of cholesterol for steroidogenesis in the ovary is derived from the uptake of plasma LDL.4 The rate-limiting step in steroidogenesis is transfer of cholesterol from the cytosol to the inner membrane of the mitochondria.5 This is mediated by an LH-induced mitochondrial enzyme called steroidogenic acute regulatory (StAR) protein.6 The StAR gene is located on chromosome 8p11.2 and codes for a 285-amino acid precursor protein, of which 25 amino acids are cleaved off after transport to the mitochondria.7,8 Nonsense mutations of the StAR gene that result in premature stop codons have been identified as a cause of congenital lipoid adrenal hyperplasia, which is characterized by the presence of intracellular lipid deposits that destroy steroidogenesis.7 Ovary steroid hormones are synthesized in both interstitial and follicular cells. The basic structure of cholesterol is three hexagonal carbon rings and a pentagonal carbon ring to which a side chain is attached (Fig. 2-1). Two important methyl groups are also attached at positions 18 and 19. Progestins and corticosteroids
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9
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21
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Androstane C19
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Progestins
Androgens
Estrogens
CH C
O
HO
O
O
O
O
Progesterone
Androstendione
Estrone
OH
O
OH
O
Testosterone
Estradiol
Figure 2-1 Structures of cholesterol (27 carbons) and of the three major classes of ovarian steroids: the progestins (21 carbons), androgens (19 carbons), and estrogens (18 carbons).
18
(pregnane series 21-carbon steroids) are produced by partial cleavage of the side chain (i.e., the desmolase reaction). Androgens (androstane series 19-carbon steroids) are produced by the total removal of the side chain. Estrogens (estrane series 18-carbon steroids) are produced by aromatization of one of the three hexagonal carbon rings to a phenolic structure with loss of the 19-methyl group. The first step in steroidogenesis is the conversion of cholesterol to pregnenolone via hydroxylation at the carbon 20 and 22 positions, which is followed by cleavage of the side chain (Fig. 2-2). From pregnenolone, steroid hormones are produced by one of two general pathways.5 The pregnenolone (Δ5) pathway produces androgens and estrogens (pregnenolone → 17OH-pregnenolone → dehydroepiandrosterone [DHEA] → testosterone → estrogen). The progesterone (Δ4) pathway produces androgens and estrogens (pregnenolone → progesterone → 17OH-progesterone → androgen → estrogen). In the adrenal gland, the Δ4 pathway produces mineralocorticoids and glucocorticoids. The enzymes involved in the intracellular synthesis of steroid hormones include five hydroxylases, two dehydrogenases, a reductase, and an aromatase. The hydroxylases and aromatase belong to the cytochrome P450 (CYP) supergene family (Table 2-1). These enzymes exist on both the mitochondria and endoplasmic reticulum.
Table 2-1 Enzyme Reaction and Cellular Location of Steroidogenic Enzymes Cellular Location/ Tissue Location
Enzyme Reaction
Gene (Enzyme)
Cholesterol side chain cleavage
CYP11A (P450scc)
Mitochondria (theca; granulosa)
17α-hydroxylase
CYP17 (P450c17)
ER (theca)
17,20-hydroxylase (lyase)
CYP17 (P450c17)
ER (theca)
Aromatase
CYP19 (P450arom)
ER (granulosa)
3β-hydroxysteroid dehydrogenase
3βHSD
ER (theca; granulosa)
17β-hydroxysteroid dehydrogenase
17βHSD
ER (granulosa)
21-hydroxylase
CYP21 (P450c21)
ER (adrenal)
11β-hydroxylase
CYP11B1 (P450c11)
Mitochondria (adrenal)
ER, endoplasmic reticulum
Of these nine enzymes, four key enzymes regulate the main steps of steroidogenesis (see Fig. 2-2): CYP11A (P450scc), a side chain cleavage enzyme that catalyzes the conversion of cholesterol to pregnenolone; 3βHSD, or 3 βa-hydroxysteroid
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Chapter 2 Ovarian Hormones Theca cells Cholesterol LH Corpus luteum
Δ4 pathway
CYP11A (P450scc)
Pregnenolone
Δ5 pathway
3βHSD
CYP17 (P450c17)
Progesterone
17OH Pregnenolone
CYP17
17,20 lyase
CYP17 17OH Progesterone
DHEA 3βHSD
CYP17 CYP21
CYP21 17βHSB
11-Deoxycorticosterone CYP11
11 Deoxycortisol
Androstenedione
Testosterone
CYP19 (P450arom)
CYP11B1
FSH
CYP19
17βHSB Corticosterone
Cortisol
Estrone
Estradiol Granulosa cells
18-OH Corticosterone
Aldosterone Adrenal gland Figure 2-2 Steroid hormone biosynthesis pathways in the ovary. The Δ4 pathway converts pregnenolone to progesterone and is the main pathway in the corpus luteum. The Δ5 pathway converts pregnenolone to androgens and subsequently estrogens and is the preferred pathway in the thecal cells. Also shown are the conversion of 17OH-progesterone to aldosterone and cortisol as a result of CYP21 and CYP11, which occurs exclusively in the adrenal gland. Irreversible reactions are denoted by a single arrow, and reversible reactions are denoted by double arrows.
dehydrogenase, which converts pregnenolone to progesterone; CYP17 (P450c17), an hydroxylase that converts pregnenolone to androgens; and CYP19 (P450arom), an aromatase that converts androgens to estrogens. Most reactions are irreversible (denoted by a single arrow in Fig. 2-2). The few reversible reactions (denoted by double arrows) are dependent on cofactor availability (e.g., NADP/NADPH ratio). The kind of hormone produced depends on the nature of the cell and the presence or absence of the inherent steroidogenic enzymes in the tissue. The adrenal cortex lacks 17βHSD; hence, adrenal androgen production is limited to DHEA and androstenedione. In the testes, LH controls 17βHSD activity and testosterone production. The steroid-producing cells of the ovary (granulosa, theca, corpus luteum) contain the full enzymatic complement for steroid hormone synthesis. In the thecal cells, LH also controls 17βHSD activity and androstenedione production, whereas CYP19 (P450arom) activity in the granulosa cells is controlled by FSH and hence estradiol production.
These relationships are the basis for the two-cell, twogonadotropin system (Fig. 2-3). Aromatization occurs in the endoplasmic reticulum. In each of the two cell types, the amount of the various enzymes differs depending on the stage of follicle development. CYP11A (P450scc) and 3βHSD are expressed in both thecal and granulosa cells of antral and preovulatory follicles and in the luteinized granulosa and thecal cells of the corpus luteum. In contrast, CYP17 (P450c17) is expressed only in the thecal cells of antral and preovulatory follicles and of the corpus luteum (see Fig. 2-3).
Steroid Hormones of the Ovary On the basis of chemical structure and biologic function, the major steroid hormones synthesized and secreted by the ovaries can be classified into three major types: estrogens, progesterone, and androgens.
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Section 1 Basic Science Pituitary gland LH
FSH
LH receptor
LH receptor
FSH receptor
Cholesterol
GTP
Gs
Cholesterol
CYP11A1
GTP
Gs
CYP11A1
GDP
GDP
Pregnenolone
Pregnenolone
CYP17 Gs
GTP
cAMP
CYP17 ATP
17α-OH pregnenolone Protein kinase A
cAMP
CYP17
Adenylate cyclase
Gs
Progesterone
3βHSD
17βHSD
CYP19
Testosterone
Androstenedione 17βHSD
Adenylate cyclase
Androstenedione
DHEA
CYP19
Testosterone
17βHSD Estradiol
Protein kinase A Estrone
Blood
Blood Thecal cell Granulosa cell Figure 2-3 Differential regulation by luteinizing hormone (LH) and follicle-stimulating hormone (FSH) of ovarian estrogen, progesterone, and androgen production, the basis of the two-cell, two-gonadotropin system. LH acts on both thecal and granulosa cells; FSH acts only on granulosa cells. FSH and LH stimulate adenylate cyclase via G protein-coupled receptors. Cyclic adenosine monophosphate (cAMP) generated from adenosine triphosphate (ATP) activates protein kinase A, which in turn stimulates steroidogenic enzymes. Gs, G protein; GDP, guanosine diphosphate; GTP, guanosine triphosphate.
Estrogens Physiologic Role
20
Estrogens are essential in the development and maintenance ofthe female phenotype, germ cell maturation, and pregnancy. In addition to their reproductive effects, estrogens also have many other nonreproductive systemic effects, such as bone metabolism/remodeling, nervous system maturation, and endothelial responsiveness.9 At puberty, estrogen stimulates breast development and enlargement and maturation of the uterus, ovaries, and vagina.10,11 Estrogen also works in concert with growth hormone and insulinlike growth factor I (IGF-I) to produce a growth spurt and stimulates the maturation of chondrocytes and osteoblasts, which ultimately leads to epiphyseal fusion.12,13 After midpuberty, estrogen begins to exert a positive feedback on gonadotropin-releasing hormone (GnRH) secretion, leading to the progressive increase of LH and FSH production, culminating in the LH surge, ovulation, and the initiation of the menstrual cycle. In the adult female, estrogen plays a critical role in maintaining the menstrual cycle.14 The cyclical changes in estradiol, progesterone, and pituitary hormones are illustrated in Figure 2-4. In the early follicular phase of the menstrual cycle, FSH stimulates granulosa cell aromatase activity, resulting in increased follicular concentrations of estrogen. The rising estrogen level further increases the sensitivity of the follicle to FSH and estrogen by increasing the number of estradiol receptors on the granulosa cells. Follicular growth and antral formation is also
promoted by estrogen. This sets up a positive feedback cycle, which culminates in one dominant follicle producing an exponential rise in estrogen levels. This exerts a negative feedback on FSH so that falling FSH levels contribute to atresia of other nondominant follicles. The dominant follicle secretes large quantities of estrogen; estradiol levels must be greater than 200 pg/mL for approximately 50 hours before a positive feedback on LH release is achieved.13,15 Once the LH surge is initiated, luteinization of the granulosa cells and progesterone production occurs. In pregnancy, estrogen augments uterine blood flow, although it is not required in itself for the maintenance of pregnancy.16 In the central nervous system, estrogen withdrawal at menopause has been associated with reduced libido, altered mood, and cognitive disturbances. These effects have been attributed to estrogen’s ability to modulate the synthesis, release, and metabolism of many neuropeptides and neurotransmitters.17 Estrogen acts as a serotoninergic agonist by increasing serotonin synthesis in the brain, which may positively influence mood.18 Although prospective observational studies in postmenopausal women have suggested that estrogen replacement therapy might protect against cognitive decline19 and the development of dementia,20 randomized trials of estrogen in the treatment of Alzheimer’s disease have shown no evidence of benefit.21–24 In the skeletal system, estrogen antagonizes the effect of parathyroid hormone by directly inhibiting the function of osteoclasts, which decreases the rate of bone resorption and diminishes bone loss. The Postmenopausal Estrogen/Progestin
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200
60
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40
100
20
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Inhibin B (pg/mL)
Inhibin A (pg/mL)
Ovarian Hormones
Biosynthesis and Metabolism
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disease.31 These studies led to the conviction that estrogen replacement therapy would consequently prevent the progression of atherosclerosis and coronary heart disease. However, the WHI study and the Heart and Estrogen/progestin Replacement Study (HERS), both large randomized, prospective trials designed to specifically address this issue, have not shown any benefit of estrogen for either the primary or secondary prevention of coronary artery disease, respectively.26,32
14
Figure 2-4 Plasma hormone concentrations (mean ± standard error) during the female menstrual cycle. Graph A, inhibins; Graph B, progesterone and estradiol; Graph C, LH and FSH. (Data from Groome NP, et al: Measurement of dimeric inhibin B throughout the human menstrual cycle. J Clin Endocrinol Metab 81:1401-1405, 1996.)
Interventions (PEPI) trial was a prospective, placebo-controlled trial designed to study the effects of hormone replacement on bone density in postmenopausal women. After 12 months of treatment with estrogen, bone mineral density increased by 1.8% at the hip and by 3% to 5% at the spine.25 The Women’s Health Initiative (WHI) showed that estrogen reduced the risk of both hip and vertebral fractures by 30% to 39%.26 In the cardiovascular system, there is strong evidence that estrogen has a natural vasoprotective role. At a cellular level, estrogen receptors are found on the smooth muscle cells of coronary arteries27 and the endothelial cells of various sites.28 Estrogen causes short-term vasodilation by increasing nitric oxide and prostacyclin release in endothelial cells.29 Several large observational studies, including the Framingham study and the Nurses Health Study, have shown that cardiovascular incidence rates are lower in premenopausal than postmenopausal women.30 There was also a significant association between a younger age at menopause and a higher risk of coronary artery
Estrogens are 18-carbon steroids derived from cholesterol (see Fig. 2-1). The three forms of naturally occurring estrogen include estrone, 17β-estradiol, and estriol. In nonpregnant females, estrone and estradiol are the main biologically active estrogens secreted by the ovary. Estradiol is almost 2 to 5 times more potent than estrone.33 The circulating levels of estradiol are 2 to 4 times higher than those of estrone in premenopausal women. Estradiol concentrations in postmenopausal women are one tenth of those in premenopausal women. Estrone concentrations do not differ with menopausal status; thus, over time, the premenopausal estradiol-to-estrone ratio is reversed.34 In contrast, estriol is not the secretory product of the ovary but is the peripheral metabolite of estrone and estradiol. The main estrogen in premenopausal women is estradiol, which is produced primarily by the granulosa cells of the ovary. Androstenedione is converted to testosterone via 17βHSD, which is rapidly demethylated at the C-19 position and aromatized to estradiol. Estradiol is also generated to some degree from androstenedione via estrone. Estrone is also a secreted product of the ovary. It constitutes the remaining circulating estrogen (40%) and is mainly derived from the extragonadal peripheral aromatization of adrenal androstenedione.35 Peripheral conversion of androgens to estrogens occurs in skin, muscle, and adipose tissue and in the endometrium.36 In the normal adult female, the production of estradiol varies according to the phase of the menstrual cycle. During the mid luteal phase, for example, the production rate is about 100 to 270 μg/day. In comparison, the production rate for androstenedione is about 3 mg/day, and with its peripheral conversion rate to estrone of about 1.5%, it accounts roughly for about 10% to 30% of estrone production per day. Secondary increases in estrone formation occur in patients with polycystic ovaries or with ovarian cancer characterized by increased androgen production. In such patients, the increased estrogen can disturb the menstrual cycle. In postmenopausal women, the ovarian contribution shrinks, leaving estrone, derived from adrenal androstenedione, as the main source of circulating estrogen.37 In the pregnant woman, the placenta becomes the main source of estrogen in the form of estriol. The placenta is unable to synthesize steroids de novo and depends on circulating precursors from both fetal and maternal steroids. Most of the placental estrogens are derived from fetal androgens (e.g., DHEA sulfate), produced by the fetal adrenal gland.38 Fetal DHEA sulfate is converted to free DHEA by placental sulfatase and then to androstenedione and testosterone before being aromatized to estrone and estradiol. Finally, it is hydroxylated to form estriol. Estradiol is rapidly converted in the liver to estrone by 17βHSD. Estrone can be further metabolized via three pathways. First, it can be hydroxylated to 16α-hydroxyestrone,
21
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Section 1 Basic Science which is then converted to estriol. Estriol is further metabolized by sulfation and glucuronidation, and the conjugates are excreted into the bile or urine. Secondly, estrone can be conjugated to form estrone sulfate, which occurs primarily in the liver. Estrone sulfate is biologically inactive and is present in concentrations that are 10-fold to 20-fold higher than concentrations of estrone or estradiol.39 Estrone sulfate can be hydrolyzed by sulfatases present in various tissues to estrone and may serve as a reserve of estrogen in an inactive form. Estrone sulfate may be of some importance in assessing estrogenicity in women and can be detected in serum as well as in urine.40 Thirdly, estrone can also be metabolized by hydroxylation to form 2-hydroxyestrone and 4-hydroxyestrone, which are known as catechol estrogens. These are then converted to the 2-methoxy and 4-methoxy compounds by catechol-O-methyltransferase. Progesterone Physiologic Role
Progesterone plays a critical role in reproduction. It inhibits further endometrial proliferation mediated by estrogen and converts the endometrium into a secretory type, preparing it not only to receive the blastocyst for implantation, but also to maintain the pregnancy. It inhibits uterine contractions and increases the viscosity of cervical mucus. Progesterone also inhibits the action of prolactin so that lactation occurs only after delivery. It raises the basal body temperature by about 0.5°C (0.9°F) and increases the sensitivity of the respiratory center to carbon dioxide (CO2), leading to hyperventilation. During pregnancy, progesterone increases insulin resistance in concert with the production of the other placental counterregulatory hormones, including placental growth hormone, placental lactogens, placental corticotropin-releasing hormone, and cortisol.41 Biosynthesis and Metabolism
Progesterone is part of the group of 21-carbon steroids, which also includes pregnenolone and 17OH-progesterone. Progesterone is responsible for all the progestational effects, whereas pregnenolone is the precursor for all steroid hormones. 17OHprogesterone has little biologic activity. Progesterone and 17OH-progesterone are mainly produced by the corpus luteum in the luteal phase of the menstrual cycle and by the placenta if pregnancy occurs. Circulating levels of progesterone at concentrations greater than 4 to 5 ng/mL (12.7 to 15.9 nmol/L) are indicative of ovulation.42 Progesterone is rapidly metabolized by the liver and has a half-life of approximately 5 minutes. It is converted to pregnanediol and conjugated to glucuronic acid in the liver. Pregnanediol glucuronide is excreted in the urine. Pregnanetriol is the main urinary metabolite of 17OH-progesterone. Androgens Physiologic Role
22
In women, androgens originate as 19-carbon steroids from the adrenals and ovaries. The major androgens produced in the ovary, primarily by the thecal cells and to a lesser degree by the ovarian stroma, include DHEA, androstenedione, and a small amount of testosterone. Both DHEA and androstenedione serve as precursors to estrogen synthesis and have little, if any, androgenic activity. However, these biologically inactive androgens are
converted by extraglandular metabolism to biologically active androgens such as testosterone and dihydrotestosterone (DHT). Normally, the levels of these potent androgens are low in females and have no significant physiologic function. Excessive production of androgens by the ovary or adrenals has been implicated as the cause of hirsutism and virilization in women.43 In contrast, in the male the androgens, of which testosterone and DHT are the most crucial, are of primary importance. Biosynthesis and Metabolism
Androgens are 19-carbon steroids derived from cholesterol. The rate-limiting step in androgen synthesis is the conversion of cholesterol to pregnenolone, which is mediated by the action of LH on the ovary and testes. In a normal ovulatory woman, the ovaries secrete approximately 1 to 2 mg of androstenedione, 1 mg of DHEA, and approximately 0.1 mg of testosterone. The majority (≈0.2 mg) of circulating testosterone is derived from peripheral metabolism of DHEA and androstenedione. Overall, testosterone production in women is about 0.3 mg/day; roughly 50% of this is derived from peripheral conversion whereas the remaining 50% is secreted equally by the ovary and the adrenals.44 In the male, more than 95% of circulating testosterone is secreted by the testicular Leydig cells. The testes also secrete small amounts of DHT and the weak androgen DHEA and androstenedione. In most androgen target cells, testosterone is converted to the biologically more potent DHT by the enzyme 5α-reductase. In the female, androgens are derived either from the adrenal cortex in the form of DHEA and androstenedione or from the peripheral conversion of these androgen precursors to testosterone and DHT. Most of the circulating testosterone is metabolized in the liver into androsterone and etiocholanolone, which are conjugated with glucuronic acid or sulfuric acid and excreted in the urine as 17-ketosteroids. Of note, only 20% to 30% of urinary 17-ketosteroids are derived from testosterone metabolism; the rest originate from the metabolism of adrenal steroids.
Transport of Ovarian Steroid Hormones in Plasma Steroid hormones are not water-soluble and require transport proteins to be carried to their target tissues. The two types of transport proteins are general carrier proteins such as albumin and transthyretin and specific carrier proteins such as thyroxinebinding globulin, sex hormone-binding globulin (SHBG), and transcortin. Both types of proteins are produced in the liver. Less than 2% of ovarian steroid hormones are free in the circulation; the remainder are mostly bound to SHBG and albumin.45,46 Sex hormone-binding globulin, a β-globulin of 95 kDa, is synthesized in the liver. Its gene is localized on the short arm of chromosome 17 (p12-13).47 It is a homodimer composed of two polypeptide chains and has a single binding site for androgens and estrogens. Dimerization is a necessary step in the binding process.48 The bound and free fractions appear to exist in a steady state of equilibrium. The amount of free fraction depends on the concentration of steroid hormone and on the levels and binding affinities of the binding proteins. Of all the steroid hormones, DHT has the highest affinity for SHBG. Approximately 98% of testosterone circulates bound to SHBG (≈65%) and albumin (≈33%). Estradiol is primarily bound to albumin (≈60%) but also to SHBG (38%); about 2%
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Chapter 2 Ovarian Hormones circulates as the free fraction.49 Progesterone, on the other hand, is mainly bound to albumin (≈80%) but also to transcortin (≈18%). Only approximately 0.6% of progesterone is bound to SHBG and about 2% exists in the free state. The metabolic clearance of these steroids is inversely related to their binding affinity to SHBG. Thus, conditions that affect levels of SHBG (e.g., pregnancy, oral contraceptives) directly affect the levels of free hormone. Because estrogens increase SHBG synthesis and androgens decrease its synthesis, SHBG levels are twice as high in women compared to men. Several other hormones and other factors are known to influence SHBG levels. Thyroid hormones increase its synthesis and release by the liver.46 Insulin, IGF-I, and prolactin have been shown to inhibit SHBG production in cultured cells.50,51 Furthermore, serum concentrations of SHBG are increased in many disease states, including hyperthyroidism and liver cirrhosis. Certain drugs, including estrogen, tamoxifen, and phenytoin, can also increase serum SHBG concentrations. Carrier protein levels are decreased by hypothyroidism, obesity, and acromegaly and by administration of exogenous androgens, glucocorticoids, and growth hormones. For many years, only the free fraction of testosterone was regarded as the biologically active component. However, researchers noted that steroid hormones bind with greater affinity to their specific carrier proteins and with much less affinity to albumin. In addition, studies of tissue delivery in vivo showed that the dissociation of albumin-bound testosterone can occur rapidly in a capillary bed so that the active fraction can be larger than the free fraction measured under equilibrium conditions in vitro.52 Thus, unconjugated steroids that are bound to albumin may be treated as free and biologically available.53,54 As mentioned above, SHBG levels can be influenced by numerous disease states. As such, changes in SHBG concentrations can result in large shifts in the free and SHBG-bound fractions. Hence, measurement of SHBG is of great clinical interest because it allows more accurate assessment of free hormones. SHBG is measured by a technique called saturation analysis, in which specific binding capacity of 3H-labeled testosterone is detected.55,56 With modifications, this method can also measure the non-SHBG bound fraction (bioavailable).57 Recently, specific nonisotopic two-site immunoassays for SHBG have become available and are used in most clinical laboratories.
Measurement of Steroid Hormones in Circulation The technique responsible for the accurate measurement of low concentrations of various steroid hormones and metabolites is competitive inhibition immunoassay or radioimmunoassay (RIA), which was originally described in 1960 by Yalow and Berson.58 However, the development of steroid immunoassays presented several problems. First, they are not immunogenic and have a similar structure—they all have a same cyclopentahaptene nucleus with only minor structural variations—which makes it difficult to generate specific antibodies. Steroids can be made immunogenic via chemical coupling to a carrier protein known as hapten, and antibodies can be raised by immunization with haptens.59 However, the site of the steroid where the protein is conjugated has a significant impact on the specificity of the resulting antibody.59 Antibodies raised to conjugates of BSA coupled at the 19th position show higher specificity than
those coupled at the 3rd or 17th positions.60 For accurate clinical interpretation, it is important to know the cross-reactivity data on each antibody that is selected for a given assay. Most commercial assay reagent manufacturers provide cross-reactivity data, but it may not always be reliable and must be evaluated in the clinical laboratories performing the assay.61 Second, the high-affinity binding proteins such as SHBG in the serum compete with the antibody and thus interfere with the measurement of steroid molecules by RIA. This makes direct measurement difficult and necessitates a preassay extraction procedure with organic solvents and often a chromatographic separation of the steroid. Alternatively, the use of certain chemicals, such as 8-anilinonaphthalene sulfonic acid can inhibit the binding of steroids to proteins, which allows the direct measurement of steroid hormones without the extraction step. Direct assays are fast and can be automated. Several automated platforms for measuring estradiol, progesterone, and testosterone are commercially available and are used in most clinical laboratories. These assays, however, have a low sensitivity and, when used to measure very low concentrations, have poor reliability.62 Therefore, they may not be the best choice for clinical applications that require the ability to measure very low hormone concentrations such as estradiol measurement in children and in men (<100 pg/mL),63 testosterone measurement in children and women(<1.5 ng/mL),64 or progesterone measurement during ovarian stimulation (<1 ng/mL).65 To overcome this problem, serum can be extracted with hexane-ethyl acetate (3:2 by volume), dried, and reconstituted in steroid-free serum, which can then be assayed in the automated platform.66 Gas chromatography combined with mass spectrometry (GC-MS) addresses many of the shortcomings of immunoassays and is considered more reliable and accurate than immunoassays. However, this technique requires multiple steps, including solvent extraction, chromatographic fractionation, and chemical dramatization before instrumental analysis, and it is often less sensitive than some immunoassays. This technique has now been superseded by liquid chromatography combined with tamdem mass spectrometry. This newer technique has a higher sensitivity and throughput than GC-MS and is considered a reference methodology.67,68 The technique has been used to simultaneously measure estradiol and estrone in human plasma with no cross-reactivity.69 These methods are recommended as reference methods and can be used to standardize and validate immunoassays, which provide the simplicity and rapid throughput needed for clinical use. Estrogens
Measurement of estradiol is important in the assessment of female reproductive function. It can be used as an aid in the diagnosis of infertility and oligomenorrhea and to determine menopausal status (Table 2-2). In addition, measurement of estradiol is widely used to monitor ovulation induction and in vitro fertilization protocols.70,71 Estrone levels are of limited clinical value in nonpregnant women because their levels closely parallel those of estradiol, except in the postmenopausal woman, in whom estrone becomes the main form of circulating estrogen. Also, as mentioned above, a specific RIA for the measurement of estrone sulfate has been described and made available commercially. Because estrone sulfate has a large circulating pool, it can serve as a marker of estrogenicity, especially in women on
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Section 1 Basic Science Table 2-2 Assay Techniques and Clinical Applications of Ovarian Steroid Hormones Hormone
Assay Techniques
Clinical Application
Estradiol
Radioimmunoassay Nonisotopic immunoassays
Evaluation of ovarian function Assessment of menopausal status Monitoring ovulation induction and in vitro fertilization cycle
Estrone sulfate
Radioimmunoassay
Marker of estrogenicity in women on hormone replacement therapy
Progesterone
Radioimmunoassay Nonisotopic immunoassays
Marker for ovulation Detection of luteal phase defects Marker for threatened abortion in early pregnancy
Total testosterone
Radioimmunoassay Nonisotopic immunoassays
Evaluation of patients with hirsutism. Male infertility
Free testosterone
Equilibrium-dialysis Diafiltration
Evaluation of patients with hirsutism. Polycystic ovarian syndrome
estrogen replacement therapy, in whom estradiol measurements are of little value due to the variable cross-reactivity of conjugated estrogens in the estradiol assays.72,73 In pregnant women, estriol is the main form of estrogen produced, and the amount of estrogen secreted increases from microgram quantities to milligram quantities. Progesterone
Although GC-MS has been recommended as the reference method for the measurement of progesterone,74 immunoassays using steroid-specific antibodies are again the preferred mode of measurement in most clinical laboratories.75,76 Both RIA and nonisotopic immunoassays for progesterone are available for commercial use. Progesterone measurement is routinely used to detect ovulation and luteal phase defects (see Table 2-2).77 In the follicular phase, progesterone levels are low (<5 nmol/L or 1.5 ng/mL). In the luteal phase, they range between 9 and 79 nmol/L (3 to 25 ng/mL). As noted, progesterone is required to maintain pregnancy, and progesterone measurement in early pregnancy can be valuable in the diagnosis of defects or threatened abortion.78 Androgens
24
The measurement of androgens, including androstenedione and total testosterone or DHT, can also be accomplished using immunoassays.79–81 The one main drawback of these assays is the cross reactivity with other steroid hormones. Interference with cross-reactive testosterone in the androstenedione assay has been overcome by the use of specific testosterone antiserum to neutralize plasma testosterone.81 Direct measurement of androstenedione and testosterone without extraction is now possible with new commercial assays. However, commercial assays demonstrate high variability, which is greatest in samples from females.82 Total testosterone in hirsute women overlaps significantly with levels seen in normal women, and measurement of free testosterone correlates better with disease.83 Free testosterone has been measured by equilibrium-dialysis, which is a time-consuming and difficult technique for most clinical laboratories to perform.
An ultrafiltration technique can be used instead, which depends on MPS-1 centrifugal gel filtration devices and correlates well with the equilibrium-dialysis method83,84 as well as with GC-MS.85 Direct, single-step, nonextraction immunoassay methods using 125 I-labeled testosterone analog have been developed commercially and are used in a number of laboratories. The accuracy and validity of this direct assay has been questioned.86,87 Alternatively, an indirect parameter of free testosterone—FAI—can be calculated as a ratio of testosterone to SHBG.88 FAI is a better discriminator of hirsutism than either total testosterone or SHBG levels.87–89 When bound with albumin and transcortin, testosterone dissociates more quickly than when bound with SHBG. This loosely bound teatosterone may be biologically available through dissociation during capillary transit. Cumming and Wall provided evidence for this hypothesis and suggested that this non-SHBG bound testosterone is a marker of hyperandrogenism.57,90 Saliva Measurements
SHBG is either undetectable or minimally present in saliva. Thus, this biologic fluid may reflect the free fraction of plasma steroids. Therefore, measurement of steroid hormones in saliva has attracted considerable attention.91–93 The ease of noninvasive collection combined with the simplicity of measurement makes salivary measurement a promising and attractive alternative to measurement of steroids in plasma. In the future, salivary assays may become useful adjuncts to those performed in plasma.94–97
PEPTIDE HORMONES AND INTRAOVARIAN GROWTH FACTORS OF OVARY The role of gonadotropins and gonadal steroids in the process of folliculogenesis in the ovary is well recognized. However, multiple other phenomena within the ovary suggest the presence of other intraovarian factors that may fine-tune the effects of gonadotropins and gonadal steroids. For example, the initiation and arrest of meiosis and the different rates of follicular growth leading to the selection of a dominant follicle point toward the existence of an intraovarian modulatory system. The concept of a gonadal factor with endocrine action at the pituitary level can be traced back more than 70 years to Mottram and Cramer.98 The first moiety was identified and named inhibin for its inhibitory effect on the pituitary.99 Since then, there has been an explosion of information regarding multiple and potential intraovarian regulators and their physiology, biochemistry, and biosynthesis as well as the identification of their receptors. Some of these compounds, which have been the subject of intense investigation, include peptide hormones/growth factors, cytokines, and neuropeptides. These factors may act in either an endocrine, autocrine, or paracrine fashion.
Peptide Hormones of the Ovary: Inhibins, Activins, and Follistatins The first water-soluble peptide hormone in testicular extracts that exerted selective inhibitory activity at the pituitary level was described in 1932 and termed inhibin.99 It was not until 1985 (almost 50 years later) that inhibin was isolated and characterized.100,101 This was followed by the identification and characterization of two other related peptide factors (i.e., activin
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Chapter 2 Ovarian Hormones and follistatin).102,103 With the cloning of inhibin α and β subunit genes,104 it was recognized that inhibin and activin belonged to the transforming growth factor-β (TGFβ) superfamily of growth and differentiation factors. Both inhibin and activin are of particular clinical interest and have been extensively reviewed3,105,106 in recent years. They have been found to exert numerous different regulatory functions in a wide variety of both normal and neoplastic cells. Follistatin, a glycoprotein that is structurally distinct but functionally closely linked to inhibin and activin, is also discussed here. The site of production and areas of clinical interest of these peptide hormones are listed in Table 2-3.
Precursor molecules: α subunit Proα
Inhibins Inhibin A
Inhibin B
The primary sources of inhibin production are the granulosa cells of the ovary and the Sertoli cells of the testis. Inhibin is also produced during pregnancy by the fetus, placenta, decidua, and fetal membranes. The main role of inhibin is to selectively suppress the production of FSH by the pituitary.107,108 This is achieved by modulating FSH biosynthesis through two main mechanisms: by reducing steady-state FSH mRNA in pituitary gonadotropes109 and decreasing the stability of FSH mRNA.110 Inhibin is a 32 kDa glycoprotein heterodimer consisting of 2 subunits, α and β, linked by disulfide bonds.111 There is a common α subunit but also two types of β subunits known as βA or βB. Thus, the two isoforms of inhibin are denoted inhibin A and inhibin B. As shown in Figure 2-5, each subunit derives from a separate precursor molecule called prepro-inhibin α (364 amino acid residues), prepro-inhibin βA (424 amino acid residues) and prepro-inhibin βB (407 amino acid residues). These are processed by proteolytic cleavage to yield the mature forms.104 In addition to the fully mature forms (αβ dimers, Mr~32,000), larger forms of dimeric inhibins with amino terminally extended α and/or β subunits have been identified in follicular fluid, which also possess FSH-suppressing bioactivity.112,113 Furthermore, monomeric forms of both α and β subunits and certain fragments (αN and proαN-αC) generated during subunit proTable 2-3 Role of Inhibins and Activins in Reproduction Site of Hormone Production
Circulating Levels
Inhibins Inhibin Granulosa cells A Antral/dominant follicle
↑ Luteal phase ↑ Pregnancy ↑ Ovarian tumors Inhibin Granulosa cells ↑ Follicular B Small developing phase follicle ↑ Ovarian tumors ↓ Perimenopause
Granulosa cells Pituitary/brain Adrenal cortex
Follistatin Granulosa cells Antral follicles
Clinical Areas of Interest/Applications
Reflect dominant follicle growth Prenatal screening for Down syndrome Marker for certain ovarian tumors Reflects total output of growing follicles Predict response to ovulation induction/IVF Marker for certain ovarian tumors Marker for the onset of menopause
↑In luteal phase ↑Spontaneous labor
Inhibits progesterone production by corpus luteum May prevent premature luteinization. May predict preterm delivery May relate to lack of follicle development
↓ PCOS ↑ PCOS
May relate to lack of follicle development
PCOS, polycystic ovarian syndrome
βA subunit βA Proβ
αC
βB subunit βB Proβ
Inhibins
Activins
αN
A
αC βA
Activin A
Activin AB
αC βB
Activin BB
Inhibins and activins
Follistatin
B
Activins
TGF-β
Follistatin and TGF-β
Figure 2-5 Activins, inhibins, follistatin, and TGFβ. A schematic representation of the formation of different dimeric proteins from three basic subunits, α, βA, and βB. Inhibins are heterodimers of α and β subunits (α-βA, α-βB); activins are homodimers of the β subunits (βAβA, βAβB, βBβB). Links between the units represent disulfide bridges.
cessing are present in follicular fluid (see Fig. 2-1) and have intrinsic biologic activities distinct from classical inhibin-like bioactivity.114,115 Because the circulation contains multiple molecular forms of inhibin, it can be difficult to accurately measure inhibin levels using conventional RIAs. Most lack specificity for dimeric inhibin due to the variable cross-reactivity of monomeric forms and of various fragments with the antibody used in the assay.112,116,117 Also, conventional inhibin bioassays based on FSH suppression or release by cultured pituitary cells lack specificity due to the FSH-regulating activities of follistatin and activins. In addition, bioassays lack the sensitivity necessary to measure inhibin levels in the circulation. The development of two-site immunoassays utilizing αβ dimer specific antibodies overcame these problems and allowed specific measurement of the two forms of inhibin dimers (A and B).118 Use of these novel two-site assays allows measurement of inhibin levels throughout the normal menstrual cycle.119 Synthesis of the two isoforms of inhibin differ during the various phases of the menstrual cycle (see Fig. 2-4). Inhibin B levels are highest during the luteal–follicular transition and the early follicular phase, and studies on its presence in follicular fluid and basal granulosa cell secretion suggest that it is secreted by small developing antral follicles.120 In contrast, inhibin A levels in the early and midfollicular phase reflect the sum of FSH- and LHstimulated inhibin A secretion from all antral follicles. Levels of inhibin A during the late follicular phase mainly reflect secretion from the dominant follicle. Hence, inhibin A and B levels can be used as markers of follicular development. Inhibins have also been investigated as prognostic markers for women undergoing assisted reproductive technologies. In particular, it was suggested that measuring inhibin B levels during the early stages of FSH
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Section 1 Basic Science stimulation for ovulation induction could predict the number of oocytes retrieved and may be useful in monitoring ovarian stimulation for in vitro fertilization. However, because there is a large overlap between normal and subnormal ovarian responses in terms of inhibin B levels, it may be just as effective to obtain Day 3 FSH or perform a clomiphene challenge test.121,122 Women in early perimenopause show significant decrease in inhibin B (no significant change in inhibin A and estradiol), which correlates with a mild increase in FSH levels. This perimenopausal decrease in inhibin B precedes a decrease in inhibin A, suggesting that inhibin B may serve as a sensitive marker for the onset of menopause.123 Studies investigating the role of inhibins in the pathophysiology of polycystic ovary syndrome (PCOS) show conflicting results. Serum inhibin B levels in early follicular phase show significant increase in some studies or no change in others124,125— this awaits future studies to confirm its role in PCOS. During pregnancy, inhibin A is produced primarily by the fetoplacental unit, whereas inhibin B levels remain low throughout the pregnancy.126 Because there is a twofold elevation of circulating inhibin A levels in the second trimester of Down syndrome pregnancies, measurement of inhibin A is a clinically useful and important test.127 When measurement of inhibin A level is added to alpha-fetoprotein, maternal age, and β-hCG (quad screen), the detection rate for Down syndrome increases from 53% to 75%.128 Inhibin A has also recently been used as a tumor marker for ovarian sex cord tumors. This heterogeneous group of tumors accounts for 7% of all malignant primary ovarian neoplasms. They are composed of granulosa cells, thecal cells, Sertoli cells, Leydig cells, and other nonspecific stromal cells. It is important to distinguish this group of tumors from carcinomas and sarcomas because the former are low-grade tumors with a better prognosis. Inhibin A and its α-subunit have been found to be sensitive immunohistochemical markers of most ovarian sex cord-stromal tumors.129 Inhibin B, however, has been found to be elevated in both sex cord-stromal and epithelial tumors and hence is of limited value in differentiating between the two entities. In addition, low levels of inhibin A in the cyst fluid of epithelial ovarian tumors has recently been reported to be associated with a worse prognosis.130 Inhibin B has been found to be the predominant inhibin secreted in males and is produced by the Sertoli cells of the testes. It also has a negative feedback role on FSH from the pituitary, and its production is regulated by spermatogenesis. Inhibin B levels correlate with sperm count and testicular volume131–133 but cannot distinguish between spermatid arrest and obstructive azoospermia—a condition in which sperm counts are normal.134 As such, it is unlikely to replace testicular biopsy in the evaluation of male infertility. Activins
26
Activins are made up of dimers of the inhibin β subunit (βAβA, βAβB, or βBβB) and have a molecular weight of approximately 25 kDa (see Fig. 2-5).135 They are predominantly produced by the granulosa cells of the ovary. Activin/inhibin mRNA and protein have also been detected in extragonadal sources, including the placental trophoblast and decidua, testes, adrenal cortex, brain, spinal cord, and anterior pituitary. This implies that activin has diverse physiologic roles that are not confined to the reproductive system.
Acting either alone or with FSH, activin exerts an autocrine effect on granulosa cells to promote and maintain granulosa cell differentiation. It promotes FSH receptor expression on small undifferentiated granulosa cells136, enhances their response to FSH and LH, and hence increases aromatase activity and estrogen production.137 This may explain how small preantral follicles progress from a gonadotropin-independent to a gonadotropindependent stage of development. After the granulosa cells acquire FSH receptors, further growth and differentiation of those cells to a preovulatory stage would be driven by activin acting in concert with FSH. Activin also inhibits both spontaneous and LH/hCG-induced increases in progesterone output by human follicles,137 implying that it plays a role in delaying the onset of premature luteinization. Activin also has a paracrine effect on thecal steroidogenesis by inhibiting thecal androgen output. It has been proposed that at earlier stages of follicular development, when the androgen requirements are low, thecal androgen synthesis is kept in check due to the relative excess of activin over inhibin and follistatin. However, as dominant follicles approach preovulatory status, increasing granulosa cell expression of inhibin and follistatin upregulates thecal androgen synthesis and ensures that the granulosa cells receive an adequate supply of aromatase substrate for conversion to estradiol. Activin stimulates pituitary FSH production, acting as a functional antagonist to inhibin (Fig. 2-6).102 It achieves this effect by increasing FSH mRNA synthesis as well as by increasing the stability of produced mRNA. Its actions are intimately modulated by intrapituitary concentrations of follistatin, which bind to activin to limit its bioavailability. Free activin levels as measured by competitive protein binding assay, using follistatin as binding protein, show very little change over the menstrual cycle.138 However, activin levels were elevated throughout the cycle in older versus younger women, suggesting that activin may play an endocrine role in maintaining FSH elevation in reproductive aging.139 Lower levels of activin are detected in PCOS patients with a simultaneous increase in inhibins and follistatin, suggesting that an imbalance in these hormones may contribute to an abnormal LH/FSH ratio.125,140 Follistatin
In the ovary, follistatin is produced by the granulosa cells in antral follicles as well as by luteinized granulosa cells, which are under the positive regulation of FSH. It modulates the function of granulosa cells in favor of luteinization or atresia by neutralizing the effects of activin. It may also directly modulate progesterone metabolism by granulosa cells.141 Follistatin is a single-chain polypeptide (315 amino acids) that functions as the binding protein for activin, thereby neutralizing it. Most of its biology is explained by its antagonism with activin. Follistatin exists in two forms; as full-length follistatin (FS 315) in the circulation and as processed follistatin (FS 288) in follicular fluid142 and the pituitary. It is part of an intrapituitary negative feedback loop where activin promotes FSH biosynthesis and the increased expression of follistatin limits its bioavailability for binding to the activin receptor on target cell membranes. It has been shown that the processed isoform of follistatin (FS 288) binds to cell-surface heparan sulfate proteoglycans with a higher affinity than FS 315.143 Because proteoglycans are anchored to cell membranes, this suggests that this would limit follistatin diffusion from the site of release, leading to high local concentrations of
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Chapter 2 Ovarian Hormones Table 2-4 Autocrine and Paracrine Growth Factors and Cell–cell Signaling in the Ovary
Brain
– – +
Hypothalamus
GnRH neurons
Pulsatile GnRH secretion
Pituitary
– +
LH LH FSH and FSH
+ – –
Factor/ Hormone
Site of Production
Site of Action (type)
TGFα and EGF
Theca cells
Theca (autocrine) Granulosa (paracrine)
Growth stimulation
Interleukin-1 Interleukin-6 Interleukin-8
Granulosa cells Granulosa cells Theca cells
Granulosa (autocrine) Theca, granulosa Theca, granulosa (auto/paracrine)
Cell differentiation
TGFβ
Theca cells Granulosa cells
Granulosa, theca (auto/paracrine)
Growth inhibition Cell differentiation
IGF-I IGF-II
Granulosa Theca
Granulosa, oocyte and theca (auto/paracrine)
Growth stimulation Cell differentiation
Bone morphogenic proteins (BMP)
Theca
Granulosa (paracrine)
Cell differentiation
Inhibins
Granulosa
Oocyte, theca, and granulosa (auto/paracrine)
Cell differentiation
Activins
Granulosa
Granulosa (autocrine)
Cell differentiation
Function
Estradiol
Growth Factors/Cytokines As Intraovarian Regulators Follicular development Inhibin Estradiol
Follistatin Activin
Mature follicle
Certain growth factors have been implicated in cellular communications within the ovary, including insulin-like growth factors IGF-I and IGF-II, epidermal growth factor (EGF), transforming growth factor-α (TGFα), basic fibroblast growth factor (bFGF), cytokines such as interleukins (IL-1 and IL-6), and tumor necrosis factor (TNFα). Growth factors and cytokines that are important as intraovarian regulators are outlined in Table 2-4.
Progesterone
Insulin-like Growth Factors Ovulation Corpus luteum
Figure 2-6 A diagrammatic presentation of the hypothalamic-pituitaryovarian axis. Developed follicles secrete steroid hormones (estradiol and progesterone) and peptide hormones (inhibin, activin, and follistatin); all collectively control secretion of gonadotropins. Estradiol and progesterone, depending on concentration, have either positive or negative feedback and can alter the frequency and/or amplitudes of pulses at the level of both the hypothalamus and pituitary.
follistatin being maintained. The membrane-anchored follistatin would be able to compete with activin receptors on nearby cells, thus modulating the biologic effects of activin. Once bound to activin, follistatin is able to accelerate the endocytotic internalization and lysosomal degradation of activin by pituitary cells.144 Follistatin levels as measured by sensitive and specific twosite enzyme immunoassay are significantly higher in women with PCOS in comparison to controls. Higher follistatin levels combined with lower activin levels in these patients suggest its role in the lack of pre-ovular follicle development and FSH suppression.125
IGF-I and IGF-II promote cellular mitosis and differentiation in a variety of systems and play an important role in modulating folliculogenesis in an autocrine/paracrine fashion.145–147 Insulin-like growth factors consist of two single-chain polypeptide growth factors that are structurally and functionally similar to proinsulin. The IGF autocrine/paracrine system includes IGFs, their specific receptors in target cells, and a family of IGF-binding proteins that regulate their bioavailability. Both IGF-I and IGF-II are produced in the ovary and augment the effects of the gonadotropins, although the main IGF in human follicles is IGF-II.148 In small antral follicles, both IGF-I and IGF-II are expressed but restricted to thecal cells. However, IGF-I receptor mRNA has been detected only in granulosa cells.146 It serves as an autocrine regulator in thecal cells and as a paracrine regulator in granulosa cells. In dominant follicles, however, no IGF-I mRNA has been detected either in thecal or in granulosa cells, and IGF-II expression is restricted to granulosa cells only. IGF-I receptors are present in granulosa cells only, and IGF-II receptors are expressed in both cell types.146 Thus, in the dominant follicle, IGF-I functions mainly as a paracrine regulator149,150 and IGF-II acts as an autocrine factor. This suggests that IGF-II has an important role in coordinating differential follicular development within the ovary.
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Section 1 Basic Science Epidermal Growth Factor (EGF), Transforming Growth Factorα (TGFα), and Basic Fibroblast Growth Factor (bFGF)
A number of other peptide growth factors have been implicated as regulators of follicular development and steroidogenesis (see Table 2-4).151 These include EGF, TGFα, and bFGF. EGF is a single-chain polypeptide of 53 amino acids with three disulfide bonds and has mitogenic effects in a variety of ectodermal and mesodermal tissues. TGFα is a 50-amino acid peptide with 30% to 40% homology with EGF. The EGF receptor is a 170-kDa glycoprotein with tyrosine kinase activity. TGFα binds to EGF receptors with the same affinity as EGF. The presence of EGF/TGFα and bFGF as well as their receptors in the ovary has been shown both at the protein and mRNA levels. The presence of immunoreactive EGF as well as EGF receptors has been identified in the preovulatory follicles152 and corpus luteum.153,154 Furthermore, studies have shown the presence of TGFα155 and bFGF156 mRNAs in follicular cells; studies have also shown that the TGFα message is upregulated by FSH in vivo. FSH plus TGFα or FSH plus EGF resulted in significantly elevated progesterone and 20α-hydroxyprogesterone levels in granulosa cells in culture.157 The presence of TGFα message in cultured granulosa cells and the fact that it mediates its action via binding to EGF receptor all point to its autocrine role in granulosa cell differentiation, follicle development, and selection. Expression of bFGF and its receptor mRNA has been detected in fetal ovaries and in granulosa cells.158,159 bFGF has been shown to be mitogenic for granulosa cells and to cause an inhibitory action on granulosa cell differentiation and thecal cell steroidogenesis.160,161 It also has potent angiogenic activity.162 Cytokines
Cytokines primarily produced by white blood cells modulate various cellular functions. The cytokines in the ovary are secreted both by the immune cells that are recruited from the circulation in the ovarian stroma and by the thecal and granulosa cells. A number of cytokines have been linked to modulation of ovarian function, including interleukins IL-1 and IL-6 and TNFα. Both IL-1 and IL-6 have been found in significant amounts in follicular fluid.163,164 Granulosa cells accounted for the majority of immunostaining for IL-1 and IL-6 in follicular aspirates, which suggests that these cytokines are produced in granulosa cells164,165 and that they affect granulosa function.166 During folliculogenesis, IL-I promotes proliferation and suppresses differentiation. In the ovulatory process, it promotes ovulation by increasing production of chemokines, steroids, ecosanoids, and vasoactive substances.167 IL-6 demonstrates inhibitory effects on both estradiol and progesterone secretion by FSH-stimulated granulosa cells.168 Elevated IL-6 levels during genital infections may provide a possible link to reproductive dysfunction. TNFα expression has also been detected in granulosa cells of human antral and atretic follicles by immunohistochemistry.169 Also, in vitro treatment with TNFα enhanced steroidogenesis in both healthy and atretic follicles,170 suggesting that TNFα has a paracrine and/or autocrine role. Nonetheless, the physiologic implications of these actions remain unclear and require further investigation. Neuropeptides
28
Some evidence suggests that an independent ovarian-central nervous system axis exists.171,172 Electrical stimulation of the
hypothalamus in hypophysectomized and adrenalectomized rats produced a change in ovarian steroidal synthesis that was independent of changes in ovarian blood flow.173 In addition, murine thecal cells can produce androgens under adrenergic stimulation.174 Adrenergic innervation of the ovary acts primarily on the thecal-interstitial cells through β2 receptors, synergizing with the effects of gonadotropins in the production of ovarian androgens.174 This may in turn play a role in the regulation of estrogen production by granulosa cells, thereby influencing follicle recruitment and selection.
REGULATION OF OVARIAN HORMONES The hypothalamic-pituitary axis plays a key role in the regulation of hormonal synthesis by the ovaries. The hypothalamus is connected to the pituitary gland via a portal vascular system that allows transport of hypothalamic releasing factors from the brain to the pituitary (see Fig. 2-6). The hypothalamus, being the coordinating center, provides precise signals via pusatile release of GnRH to the gonadotrophs, which in turn secrete LH and FSH. Any interruption in this connection results in low gonadotropin levels, leading to failure of ovarian hormone secretion.
Hypothalamic Regulation Gonadotropin-releasing Hormone
The gonadotropin-releasing activity in hypothalamic extracts was first demonstrated in the late 1950s. In 1971, almost 15 years later, GnRH was first isolated and characterized from a hypothalamic extract. This was followed by its synthesis and its clinical availability. However, early clinical studies proved disappointing until the nature of its pulsatile secretion was recognized. In their classic experiment in the rhesus monkey, Knobil and colleagues showed that normal LH and FSH release required the pulsatile infusion of GnRH at approximately 60-minute intervals175 Furthermore, a change in pulse frequency (lesser or greater) or continuous infusion resulted in failure of LH and FSH secretion and release (Fig. 2-7).176 These observations were confirmed in humans. Pulsatile GnRH infusion reproduces appropriate patterns of hormonal changes, resulting in ovulation and fertility in women with hypothalamic amenorrhea. Physiologic Role of GnRH
GnRH is produced by secretory neurons located in the arcuate nucleus of the medial basal hypothalamus and the preoptic area of the anterior hypothalamus. The nerve terminals are found in the lateral portions of the external layer of the median eminence adjacent to the pituitary stalk.177 GnRH has an intrinsically pulsatile pattern of secretion, which is under the control of a hypothalamic pulse generator in the arcuate nucleus.178,179 The frequency and amplitude of the pulsatile rhythm of GnRH secretion are crucial in regulating gonadotropin secretion and hence gonadal activity.180,181 Physiologic frequency (approximately hourly pulses) tends to upregulate GnRH receptors, enhancing pituitary responsiveness to subsequent stimulation by GnRH. This leads to a “self-priming” effect, whereby LH levels have been shown to increase sequentially with sequential GnRH pulses. A longer frequency causes anovulation and amenorrhea; a shorter frequency or constant exposure to GnRH downregulates the GnRH receptors, inducing refractory gonadotropin responses.176,182–184
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Chapter 2 Ovarian Hormones Continuous
including acetylcholine, catecholamines, serotonin, opioids, and γ-aminobutyric acid.185 Norepinephrine is believed to stimulate GnRH release whereas opioids exert inhibitory effects. Dopamine can produce both inhibitory and excitatory GnRH responses, depending on the physiologic state.186
Pulsatile 200
15
150
10
100
5
50
0
FSH (ng/ml)
LH (ng/ml)
Pulsatile 20
Biochemistry and Biosynthesis
GnRH is a linear decapeptide, derived from the post-translational processing of a large precursor molecule, prepro-GnRH. The prepro-GnRH molecule consists of 92 amino acids in a tripartite structure (Fig. 2-8). It begins with a signal peptide of 23 amino acids, which is followed by the decapeptide and then a Gly-LysArg sequence needed for proteolytic processing and C-terminal amidation of GnRH molecules. The last 56 amino acid residues are collectively known as the GnRH-associated peptide (GAP), which may have prolactin-inhibiting activity.187,188 Knowledge of GnRH structure led to the development of many clinically important long-acting GnRH agonists, including buserelin, leuprolide, and nafareline (see Fig. 2-8). Gonadotropin-releasing hormone is encoded from a single gene on the short arm of chromosome 8p21-p11. The human gene contains 4 exons; exon 2 encodes pro-GnRH, exon 3 and part of exon 2 and 4 encode the GAP protein, and exon 4 encodes a long 3′ untranslated region. Molecular processing occurs primarily in the nucleus of the cell body (soma). After transcription, the mRNA is transported to the cytoplasm where translation takes place and it is converted into the decapeptide. GnRH and its cleavage products, GAP and pro-GnRH, are then transported to the nerve terminals where they are secreted in tandem into the portal circulation.187,189,190
0 10
5
0
5
10
15 Days
20
25
30
35 40
Figure 2-7 Change in luteinizing hormone (LH) and follicle-stimulating hormone (FSH) levels in gonadotropin-releasing hormone (GnRH) deficient monkeys, according to the mode of delivery of GnRH. A continuous infusion decreased both LH and FSH levels, which are restored by pulsatile GnRH administration. (Data from Belchetz PE, et al: Hypophysial responses to continuous and intermittent delivery of hypopthalamic gonadotropinreleasing hormone. Science 202:631-633, 1978.)
The “pulse generator” is subject to modification by two main inputs: (1) hormone-mediated signals and (2) neural signals. Hormone signals include negative and positive feedback from the gonadal steroids (e.g., estrogen and progesterone) as well as gonadal protein hormones. Neural signals may come from a wide variety of sources and are mediated by neurotransmitters,
C terminal
Pre-pro-GnRH
1
2
3
4
5
6
7
8
9
10
Glu
His
Trp
Ser
Tyr
Gly
Leu
Arg
Pro
Gly
GnRH associated peptide (56aa) N terminal Native GnRH
1
2
3
4
5
6
7
8
9
10
pyroGlu
His
Trp
Ser
Tyr
Gly
Leu
Arg
Pro
Gly-amide
6 D-Ser
Leu
Buserelin (agonist)
1
2
3
4
5
pyroGlu
His
Trp
Ser
Tyr
(tertButly)
7
8
9
Arg Pro-ethylamide
Leuprolide (agonist)
Figure 2-8
1
2
3
4
5
6
7
pyroGlu
His
Trp
Ser
Tyr
D-Leu
Leu
8
9
Arg Pro-ethylamide
The structures of native gonadotropin-releasing hormone (GnRH) and some analogs currently in clinical use.
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GnRH has a short half-life (2–4 min) due to its degradation by peptidases in the hypothalamus and pituitary gland. These peptidases cleave the molecule at the Gly-Leu bond and at position 10. Due to the large dilutional effect, peripheral GnRH serum levels are too low for pulse characteristics to be determined reliably in humans. However, the simultaneous measurement of circulating levels of LH in hypophysial-portal and peripheral blood samples in other species has been shown to correlate closely with GnRH release.191,192 As such, frequent measurements of LH pulses can be used as an accurate indicator of GnRH secretion patterns. FSH also correlates with GnRH secretion, but is less useful due to its long half-life.
these cells responsive to LH and augmenting progesterone secretion. Progesterone then increases FSH release in midcycle. Biochemistry and Biosynthesis
The anterior pituitary produces three glycoprotein hormones: LH, FSH, and thyrotropin-stimulating hormone (TSH), all of which share a similar biochemical structure. Each consists of a heterodimer of two noncovalently linked protein subunits, αβ. Each subunit is cysteine-rich and contains multiple disulfide linkages (Fig. 2-9). There are also multiple carbohydrate moieties on both subunits that are important in the metabolism and biologic activity of the hormones.200,201 The α subunit is common to all three hormones, whereas the β subunit is unique.
Regulation by Pituitary Hormones As mentioned above, GnRH action on gonadotrophs stimulates gonadotropin production and release in a pulsatile fashion. In addition, LH and FSH release from the pituitary is also affected in both a positive and negative manner by estrogen and progesterone as well as by the protein hormones secretion by the ovaries (see Fig. 2-6). The positive effect of estrogen and the negative effect of progesterone on the gonadotropins depend on the level of steroid hormone and the duration of exposure to the gonadotrophs. On the other hand, both LH and FSH are required for ovarian estrogen synthesis and the level of estrogen production depends on the time of exposure and the level of gonadotropins.193,194 Nonetheless, a disordered signal from the pituitary gland may result in infrequent ovulation (oligo-ovulation) or absent ovulation (anovulation).
Glu56Ala LH
α 1
S
30
As discussed above, LH regulates ovarian steroidogenesis. The surge of LH in the middle of the menstrual cycle is also responsible for inducing ovulation. The surge occurs as a result of a dramatic rise in estradiol produced by the preovulatory follicle, which produces a positive feedback on LH. The midcycle surge stimulates the resumption of meiosis and the completion of reduction division in the oocyte with release of the first polar body. Proteolytic enzymes and prostaglandins are increased in response to LH, leading to a release of the oocyte from the ovary.195 Finally, the continued secretion of LH after ovulation converts the remaining follicular cells in the ovary to the corpus luteum and stimulates the corpus luteum to produce progesterone by enhancing the conversion of cholesterol to pregnenolone. Follicle-stimulating hormone regulates ovarian estrogen synthesis by binding to the FSH receptor on the surface of the granulosa cell and is required for follicular maturation and growth.196,197 This results in elevated cyclic adenosine monophosphate (cAMP) levels and the induction of aromatase, which converts androstenedione from the neighboring thecal cells to estrone. FSH also induces expression of 17βHSD type 1, which converts estrone to estradiol. Increased secretion of estradiol leads to further proliferation of granulosa cells and follicular growth and an increase in the number of estradiol receptors.196,198,199 In the mature follicle, FSH and estradiol increase the LH receptors’ expression in granulosa cells, making
Y 78 92
S Y 30
β 1
121
IIe15Thr
Glu54Arg
Ser102Gly
Trp8Arg FSH
α Regulation by Luteinizing Hormone and Follicle-stimulating Hormone Physiologic Role
Y 52
1
β
S Y
Y
7
24
Y
Y
62
78 92
S
1
110
Cys51Gly Val61Δ2bp stop87
Cys82Arg
hCG
α 1
S Y 13
β
Y
Y
52
78 92
S Y 30
0
0
0
0
122 127 132 137
1
145
Val79Met Figure 2-9 A schematic presentation of the gonadotropin subunits, showing the sizes, locations of carbohydrate side chains, and currently known mutations and polymorphisms: The symbols Y and O represent the locations of the N-linked and O-linked carbohydrate side chains, respectively. The symbol S represents disulfide bonds. The arrows indicate the positions of point mutations/polymorphisms. The numbers below the right end of the bars indicate the number of amino acids in the mature subunit protein. Cα, common α subunit; LHβ, luteinizing hormone β subunit; FSHβ, follicle-stimulating hormone β subunit; HCGβ, human chorionic gonadotropin β subunit. (Adapted from Huhtaniemi I: Functional consequences of mutations and polymorphisms in gonadotropin and gonadotropin resistant genes. In Leung PCK, Adashi E (eds): The Ovary, 2nd ed. London, Elsevier Academic Press, 2004, p 56.)
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Chapter 2 Ovarian Hormones α Subunit
The human α subunit gene is located on chromosome 6p21.123 and is composed of 4 exons. The first exon is noncoding. The gene encodes a 14-kDa polypeptide that consists of a 24-amino acid signal peptide and the mature α subunit of 92 amino acids with 10 cysteine residues and two N-linked oligosaccharide groups.202 The cysteine residues participate in the intrasubunit disulfide linkages. The α subunit is more abundant than the β subunit, and unassociated, or “free,” α subunits are present in the serum and pituitary. They have little known biologic activity. Hence, only the αβ heterodimer possesses biologic activity.
Regulatory domain A/B
DNA binding domain C
Mutations in Gonadotropin Genes
Although rare, mutations in gonadotropin genes can result in clinical disorders, which have been described in the literature. In fact, the subject has been recently reviewed extensively.201,209 There are several reports of neutral polymorphisms, but no activating mutations have been reported so far in the α subunit gene.209 Examples of mutations in the LHβ subunit include a single amino acid substitution (Glu to Arg) at codon 54210 that is associated with hypogonadism in homozygous males and with a high incidence of infertility in heterozygotes. In addition two point mutations—Trp to Arg at codon 8 and Ile to Thr at codon 15—have been described in five women with immunologically anomalous LH but with hyperbioactivity.211 However the direct relationship of these mutations with a specific pathogenesis remained elusive. The other variant of LHβ (polymorphism) with substitution of Serine to Glycine at codon 102 in exon 3 has been found to be population-specific in 4% of women in Singapore with menstrual disorders. Several inactivating mutations have been described in the FSHβ subunit gene (see Fig. 2-9). The first mutation reported
Ligand binding domain E
A
mRNA
Nucleus
Pre-mRNA
β Subunit
The β subunits for LH and FSH are encoded by separate genes and are located on different chromosomes. The gene coding for the LHβ subunit consists of three exons and is present in a complex gene cluster on human chromosome 19q13.3.203 The cluster includes six chorionic gonadotropin β (CGβ) genes that are presumably derived from single ancestral LHβ gene by gene duplication.204 Both LHβ and CGβ proteins are structurally and functionally similar. They are approximately 80% homologous in amino acid sequence. Both propeptides contain a 20-amino acid signal sequence. The mature LHβ and CGβ subunits consist of 121 and 145 amino acids, respectively. The major difference between LHβ and CGβ proteins is the presence of a 24-amino acid C-terminal peptide in CGβ, which is heavily glycosylated, with four O-linked carbohydrate moieties (Fig. 2-10). The gene for the FSHβ subunit is located on the short arm of chromosome 11p13 and, like the gene for LH, it consists of three exons.205 The molecular size of FSH is 33 kDa, consisting of a signal peptide of 18 amino acids and the mature FSHβ protein of 111 amino acids. Like α subunits, both LHβ and FSHβ subunits contain 10 cysteines for disulfide formation. Compared to FSHβ and CGβ subunits, LH does not have a terminal sialic acid on its carbohydrate side chain. This results in a shorter metabolic clearance time for LH, compared to FSH and HCGβ subunits. HCGβ has the highest content of sialic acid and has the longest half-life.206,207 Deglycosylation of gonadotropins has no effect on receptor binding but abolishes signal transduction.208
Hinge region D
HRE C C
CA AB 1
Hormone binding
AB E
C
DNA binding
3
Dimerization
2
Dissociation of HSP90
E
AB Protein
4
E
HSP90 HSP90 Steroid hormone (estrogen)
Cytoplasm
B Figure 2-10 Basic structure and general mechanism of action for cytoplasmic/nuclear steroid hormone receptors. A, Basic structure of steroid hormone receptor. B, Mechanism of action involving steps 1–6 as described in the text. HSP90, heat shock protein; HRE, hormone response element; CA, coactivators.
was a homozygous 2bp deletion in a codon 61 (Valine) in a woman who presented with delayed puberty, amenorrhea, and infertility.212 The mutation was a nonsense mutation leading to altered amino acid sequence after codon 60, leading to a stop codon at residue 87. The mutated protein was altered and was thus unable to associate with the α subunit and was nonfunctional. The patient was treated with exogenous FSH, leading to follicle maturation and pregnancy. Another case report on FSH mutation with a similar phenotype was found to be heterozygote for two FSH mutations: the first was a nonsense mutation at codon 61 and the second was a substitution of Cysteine to Glycine at codon 51. The loss of the cysteine residue was likely responsible for the altered conformation change and loss of function leading to the phenotype.213 An inactivating mutation leading to the substitution of Cysteine to Arginine residue at codon 82 was described in an infertile man.214 Measurement of LH and FSH
It has been difficult to develop highly specific immunoassays for the gonadotropins due to the high homology of the glycoprotein
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32
hormones as well as the need to distinguish between free α subunits and intact hormones. Cross-reactivity with the α subunit has made it difficult to accurately measure LH and FSH with RIAs that use polyclonal antibodies.215–217 In addition, there is microheterogeneity in both pituitary and circulating gonadotropins due to the degree of glycosylation. Variation in oligosaccharide content and structure also causes charge microheterogeneity, resulting in serum isoforms that separate over the pH range of 6.5 to 10 on electrofocusing.218 Although the clinical significance of this microheterogeneity of circulating isoforms remains unknown, it affects immunoreactivity as detected by various antibodies, all of which lead to variability among different immunoassays. Microheterogeneity also affects the biologic activity and may be primarily responsible for the discrepant results generated by immunoassays versus bioassays. The other problem stems from a lack of a suitable reference preparation for both immunoassays and bioassays. The international reference preparation (IRP) of purified human urinary menopausal gonadotropins (2nd IRP-hMG) was established by the World Health Organization (WHO) and has been widely used in most immunoassays and bioassays. The unitage assigned to IRP was defined by bioassays and formed the basis of all subsequent purified pituitary preparations as, for example, the WHO international standard (2nd IS). Most commercial assays are calibrated against 2nd IS. Although the biologic potency estimates are given for the IRP or IS, the immunoreactivity varies in different immunoassays depending on the antibody specificity. In recent years, two-site directed immunoradiometric (IRMA) or immunochemiluminometric (ICMA) assays have been developed and are based on the use of two monoclonal antibodies. These have helped overcome most limitations of RIAs.219 These assays are automated and show exquisite sensitivity approaching 0.1 mIU/mL. Furthermore, these assays are not affected by the presence of free α subunits and correlate better with bioassays. The high sensitivity of these assays also allows detection of low levels seen in early puberty. Luteinizing hormone bioassays utilize dispersed mouse or rat Leydig cells or a Leydig cell tumor cell line (MA-10) in culture220,221 and measure testosterone production in vitro. These assays measure the biologic activity of circulating LH under physiologic conditions. This is important because the biologic activity of LH changes with alterations in glycosylation and the tertiary structure of the molecule. The combination of bioassay and RIA permits the calculation of bioactive/immunoreactive ratios, which can provide a useful index of qualitative changes of the LH molecule.219,222 Although the bioactive and immunoactive LH profiles are generally well correlated during physiologic changes, significant discrepancies can occur in some pathologic states. For example, inactivating mutations in the LHβ gene result in elevated levels of immunoreactive LH but a marked loss of bioactivity. In vitro bioassays for FSH activity using rat granulosa cells or Sertoli cells measure production of cAMP or aromatase activity in response to FSH. The sensitivity of these assays is about 2.5 mIU/mL. Alhough in vitro bioassays have been valuable in elucidating the physiology, they remain cumbersome and time consuming and are not practical for routine clinical use. Measurement of LH and FSH is useful in the diagnosis of gonadal function disorders (Table 2-5). Elevated levels of FSH generally indicate ovarian failure but may be seen in some
Table 2-5 Role of Pituitary Hormones in Assessment of Female Infertility Hormone
Hormone Levels
Interpretation
Prolactin
↑Prolactin
Evaluate for prolactinoma after excluding hypothyroidism, pregnancy, macroprolactinemia as cause.
LH and FSH
↓ LH, ↓ FSH
Hypothalamic or pituitary disease
↑ LH, ↑ FSH
Premature ovarian failure
↑ LH, ↓ or normal FSH
Polycystic ovary syndrome
patients with viable ovarian follicles.223 Although rare, high gonadotropin levels associated with gonadotropin-secreting pituitary tumors or ectopic gonadotropin-producing tumors. In an amenorrheic patient, an elevated LH level with normal FSH and LH-to-FSH ratio typically (but not invariably) of greater than 2 is suggestive of PCOS. Low levels of these hormones are indicative of pituitary or hypothalamic dysfunction and occur together with low serum estradiol levels. For further assessment of pituitary reserve, provocative GnRH testing is required. LH and FSH responses to intravenous injection of 100 μg GnRH are measured at 20 and 60 minutes. Lack of response may suggest the likely diagnosis of hypogonadotropic hypogonadism; however, its sensitivity and specificity are low in patients receiving exogenous sex steroids.224 Prolactin Physiologic Role of Prolactin
The main role of prolactin is the stimulation of lactation in the postpartum period. Its effect is blunted by estrogen and progesterone; the decrease in both these hormones after parturition allows lactation to occur. Prolactin also acts at the hypothalamus to suppress gonadotropin production, primarily by inhibiting the pulsatile secretion of GnRH. Thus, conditions associated with hyperprolactinemia can cause hypogonadism, which leads to shortened luteal phases, decreased numbers of granulosa cells, anovulation, and amenorrhea in women. In men, excess prolactin can lead to decreased spermatogenesis, decreased libido, impotence, and infertility. Biochemistry and Biosynthesis
Prolactin is a single polypeptide with a molecular weight of 22 kDa. It consists of 198 amino acids and is folded into a globular shape connected by disulfide bonds. It is remarkably homologous to human growth hormone (hGH) and human placental lactogen (hPL). The gene for prolactin is found on chromosome 6, and seems to have been evolutionarily derived from a common somatomammotropic (hGH-hPRL-hPL) precursor. It is produced by lactotrophs in the pituitary, which make up almost 50% of the total pituitary cell population. Its production is under tonic inhibition by dopamine, produced by the tuberoinfundibular cells, and the hypothalamic tuberohypophyseal dopaminergic system. Prolactin is extremely heterogeneous and exists in at least four different molecular forms225–227: (1) little prolactin, molecular weight (MW) 23 kDa, a nonglycosylated monomeric hormone with high receptor binding and bioactivity; (2) G, or glycosylated prolactin, MW 25 kDa, which has reduced immunoreactivity; (3) big prolactin, MW 50 kDa,
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Chapter 2 Ovarian Hormones consisting of a mixture of both dimeric and trimeric forms of G prolactin; and (4) big-big prolactin, MW 100 kDa, consisting of G prolactin covalently coupled with an immunoglobulin, also known as macroprolactin. The big and big-big forms have lower receptor-binding affinity, but may be converted to little prolactin by reduction of the disulfide bonds. As such, discrepancies can exist between measured prolactin levels and the clinical effects. Measurement
Prolactin levels are measured by use of IRMA and ICMA. These methods give excellent reproducibility, sensitivity, and assay efficiency; however, they vary in their abilty to react with biologically inactive macroprolactin. Hence, a measured serum immunoreactive prolactin level often does not correlate with expected clinical effects. A polyethylene glycol precipitation method should be used to detect the macroprolactinemia.228 The other caveat is that these samples are usually assayed at a single dilution. As such, extremely high levels of prolactin (≈1000 ng/mL), such as those seen in macroprolactinomas, may saturate both capture and localizing antibodies, leading to a falsely low value in some one-step sandwich immunoassays. This has been known as the hook effect. Thus, in patients with macroadenomas, a 1:100 serial dilution should be performed if the assay is prone to this hook effect.
MECHANISMS OF ACTION OF HORMONES Ovarian/pituitary hormones circulate in very low concentrations in the extracellular fluid, generally in the range of 10–15 to 10–9 mol/L. To exert their biologic effects on the target cells, special recognition mechanisms are required. Target cells are able to discriminate between the different hormones at low concentrations by depending on cell-associated recognition molecules called receptors. Hormones exert their biologic effects by interacting with these high-affinity receptors, which in turn trigger one or more effector systems within the cell. The high affinity, specificity, and receptor expression level together define the nature and degree of biologic response of a hormone. All receptors have at least two functional domains, a recognition domain and a signal-generating domain. The recognition domain binds to the hormone, and the second domain generates a signal that couples hormone recognition to some intracellular function. This coupling of hormone binding to signal transduction, or receptor–effector coupling, provides the first step in the amplification of a hormonal response and distinguishes the target cell receptor from the plasma carrier proteins that bind hormone but do not generate a signal. Just on the basis of the location of the hormone receptor (i.e., intracellular/nuclear or cell surface), two distinct mechanisms of hormone actions can be classified. These mechanisms further differ by the nature of the signal transduction pathway or second messenger responsible for mediating hormone action (Table 2-6). Examples of nuclear receptors include steroid hormones that are lipophilic and pass through the cell membrane to interact with receptors located either within the cytoplasm or the nucleus. This in turn affects gene transcription within the nuclear compartment. Polypeptide hormones (i.e., LH, FSH, hCG, GnRH, inhibins, and activins) and growth factors that are hydrophilic interact with cell-surface receptors that are located
Table 2-6 Classification of Receptors for Steroid and Peptide Hormones Hormones that Bind to Intracellular/Nuclear Receptors
Hormones that Bind to Cell Surface Receptors
Type 1 receptor, classical steroid hormone receptor Requires ligand binding for activation Homodimerization pattern Estrogen receptor Progesterone receptor Androgen receptor Glucocorticoid receptor Mineralocorticoid receptor
Seven-transmembrane domain receptors Second messenger is cAMP LH FSH Second messenger is calcium and/or phosphatidylinositols GnRH TRH Second messenger is cGMP Nitric oxide Atrial natriuretic factor
Type 2 receptors
Single-transmembrane domain receptors Intrinsic kinase activity Second messenger is tyrosine kinase IGF Insulin EGF Second messenger is serine kinase Activin TGFβ Aquired kinase activity by interaction with transducer molecules Growth hormone Prolactin
Able to bind DNA in the absence of ligand, exerting repressive effect Heterodimerization pattern Thyroid Hormone Retinoic Acid Receptor Vitamin D receptor Retinoid X receptor Orphan receptor A. Ligand unknown
on the plasma membrane. They trigger a plethora of signaling activity in the membrane and cytoplasmic compartments as well as exerting parallel effects on the transcriptional apparatus in the nuclear compartment. These cell surface receptors can be further classified based on the second messenger into four major subgroups, as listed in Table 2-6.
Steroid Hormone Action Nuclear Receptors Superfamily
Steroid hormone nuclear receptors (estrogen receptor [ER], progesterone receptor, and androgen receptors) are ligandinducible transcription factors that regulate the expression of target genes involved in reproduction and metabolism. They belong to the superfamily of nuclear hormone receptors and share many structural and functional features.229 Other members of the superfamily include receptors for glucocorticoids, mineralocorticoids, thyroid hormones, 1,25-dihydroxy vitamin D3, retinoic acid, and an ever-increasing number of orphan receptors, which show structural similarity but for which ligands are not known. Within this nuclear receptor superfamily, three main groups have been identified based on the differences in their functional and recognition characteristics230: type 1, or steroid receptor subclass; type 2, or thyroid/retinoid/vitamin D3 receptor subclass; and a third subclass of orphan receptors. Type 1 (“Steroid” or “Classical”) Receptor Subfamily
This includes the ER as well as the progesterone, androgen, glucocorticoid, and mineralocorticoid receptors. These receptors cannot bind to DNA in the absence of ligand and thus remain functionally silent. They exist as cytoplasmic/nuclear, multimeric complexes that are in association with heat shock proteins (e.g., HSP90, HSP70, and HSP56). The association of the
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Section 1 Basic Science ligand with the receptor and dissociation of the heat shock proteins are required for activation of the receptor.
ligand binding is responsible for interaction with coactivators or corepressors.
Type 2 Receptor Subfamily
Cellular Mechanism of Action of Steroid Hormones
This includes the thyroid hormone, vitamin D3, and retinoic acid receptors, as well as the retinoid X receptor. In the absence of ligand, these receptors can bind to DNA and exert the repressive effect or silence their respective promoters. Unlike steroid receptors, type 2 receptors bind constitutively to response elements and are capable of forming heterodimers with the retinoid X receptor. These interactions may serve to modulate the amplitude of the transcriptional response to the ligand. Most of the early knowledge about steroid hormone mechanism of action has been derived from in vitro and in vivo binding studies that used radiolabeled estradiol as a ligand.231 The role of ERs in the regulation of breast cancer growth has been well studied over the past four decades; it was the first steroid receptor to be discovered in the early 1960s. This led to the subsequent elucidation of a general pathway for steroid hormone action. In general, nuclear receptors share a common protein architecture consisting of five functional domains232 as illustrated in Figure 2-10A. Amino-Terminal Transactivation Domain (A/B Region)
This is the most variable domain in terms of sequence and length in the family of nuclear receptors. It can range in size from 20 amino acids in the vitamin D3 receptor to 600 amino acids in the mineralocorticoid receptor. It usually contains a transcription activation function (TAF-1), which interacts with other core transcriptional machinery (e.g., coactivators) to activate target gene transcription. Central DNA-binding Domain (C Region)
This region is essential for activation of transcription. It encodes two zinc finger motifs and has a very high degree of homology among all types of nuclear receptors. Hormone binding to the receptor induces specific conformational changes in this region, allowing receptor binding to the hormone-responsive element (HRE) of the target gene. The amino acid sequence that lies between the first and second zinc fingers (i.e., the recognition helix) is responsible for establishing specific contact with the DNA. The second zinc finger stabilizes the contact and increases the affinity of the receptor for the DNA. Hinge Region (D Region)
As the designation hinge indicates, this region is the site of rotation that allows the protein to alter its conformation after ligand binding. It provides the localization signal that is important for moving the recptor to the nucleus in the absence of ligand and contains a nuclear localization domain (glucocorticoid and progesterone receptors) and/or a transactivation domain (thyroid hormone or glucocorticoid receptors). Carboxy-Terminal Ligand-Binding Domain (E Region)
34
This region is responsible for binding of the relevant ligand and is responsible for receptor dimerization or heterodimerization. It also contains the binding site for heat shock proteins and has a transactivation function (TAF-2) that can drive transcriptional activity. Unlike TAF-1, its transcriptional activity depends on hormone binding. Conformational change that occurs after
The steroid hormone nuclear receptors are known as liganddependent transcription factors. Binding with their ligands is a necessary step for their function as transcriptional regulators. Unliganded receptors may be localized to either the cytoplasm (e.g., glucocorticoid receptor) or the nucleus (e.g., estrogen, progesterone, and thyroid hormone receptors). For most steroid hormones the unliganded receptors exist in the cell nucleus as large molecular weight oligomers (≈300K; 7-10S sedimentation rate)233 and can be isolated in cytosolic fraction from cells or tissues disrupted in hypotonic media. The oligomers are formed by noncovalent association of a monomeric receptor protein with a dimer of heat shock protein (HSP90, HSP70, or HSP56).234 The general features of the mechanism of action of these hormones are depicted in Figure 2-10B. Steroid hormones that freely diffuse through the cell membrane bind to the specific receptors in the nucleus. Ligand binding to receptor initiates the receptor transformation, or so-called activation process. During this process the receptor undergoes conformational changes that primarily occur as a result of its dissociation from HSP, which exposes the DNA-binding site. Nuclear translocation and dimerization of the activated receptor then occurs. Most evidence suggests that this process is thermodynamically irreversible. The hormone receptor complex then binds to a specific region of DNA, the HRE, which is located upstream of the gene. The first HRE was identified for the glucocorticoid receptor. Later the HREs for the progesterone, androgen, estrogen, and mineralocorticoid receptors were shown to be similar to that of the glucocorticoid receptor.235–237 The steroid HREs in the target genes are a palindromic (inverted-repeat) DNA sequence of 15 base pairs (Table 2-7). This interaction leads to the recruitment of a host of ancillary factors known as coregulators (coactivators or corepressors), creating a transcriptionally permissive or nonpermissive environment at the promoter, as well as communicating with other general transcription factors and RNA polymerase II. Coactivators function as adaptors in a signal transduction pathway. The binding of these coregulators modulates the resulting transcription (i.e., the activation and inactivation of specific genes). Hormone antagonists, for example, induce a different conformation in the TAF-2 that hinders the coactivator-binding site and recruits a corepressor instead, and inhibits gene expression. The availability of these coregulators in Table 2-7 Sequence of DNA Recognition Elements for Steroid Hormone Receptors Steroid Hormone Receptor
Element
DNA Recognition Sequence
Estrogen receptor
ERE
AGGTCAsssTGACCT
Progesterone receptor
HRE
AGAACAsssTGTTCT
Androgen receptor Glucocorticoid receptor Mineralocorticoid receptor Sequences read 5′-3′ direction indicated by arrows. S indicates spacer nucleotides (A, G, C, or T).
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Chapter 2 Ovarian Hormones responsible for estrogenic effects in other tissues, including the uterus. 17β-estradiol binds to the estrogen receptor with a much higher affinity than estrone or estriol. In addition, the binding of estradiol to its receptor and its subsequent activation also enhances cooperativity, meaning that the action of estradiol binding to one site increases the affinity for it to bind to another site, enabling the receptors to respond to small changes in hormone concentration. Estrogen’s relatively long duration of action is also due in part to the high-affinity state achieved by its receptor. On the other hand, clomiphene exerts its antiestrogenic effects by negative cooperativity, preventing the transition of the estrogen receptor from its low-affinity state to its highaffinity state. The two receptors (ERα and ERβ) are differentially expressed in different tissues, leading to the differences in the response to the same hormone subtypes.243,244 The α receptors are predominantly expressed in breast cancer tissue, ovarian stroma, and endometrium. ERβ receptors, on the other hand, are expressed in several nonclassic target tissues, including the kidney, intestinal mucosa, lung, bone, brain, endothelial cells, and the prostate gland. 17β-estradiol and estrone have a higher affinity for α receptors and thus exert their effects predominantly on target tissue with α receptor expression. Phytoestrogens such as genistein and coumestrol, on the other hand, bind predominantly to β receptors245 and would be expected to exert their effects on target tissues expressing these receptors. The conformational change of the ligand-binding domain also differs in both α and β estrogen receptors, depending on which ligand has been bound to the receptor.244 This distinct conformational change is the major factor that determines the receptor’s ability to interact with coactivators or corepressors. For example, estradiol activates transcription when it binds to ERα but inhibits transcription when bound to ERβ. Raloxifene and tamoxifen, on the other hand, inhibit transcription when forming complexes with ERα and activate transcription when bound to ERβ. The differential expression of target tissue adaptor proteins and phosphorylation also affect gene transcription. A higher concentration of coactivators or corepressors in the target tissue can affect the cellular response of that tissue to the same ligand. Phosphorylation of the receptor by protein kinases increases the transcriptional activity of the receptor. For example, growth factors such as epidermal growth factor and IGF-I can stimulate
different tissues plays an important role in defining the biologic response to both steroid hormone agonists and antagonists.238 The biologic activity of a hormone is determined by at least four factors intimately related to the structure of the hormone receptor in question. The first factor is the affinity of the hormone for the hormone-binding domain of the receptor. The second factor is the differential expression of receptor subtypes in the target tissue, altering the response to the same hormone. The third factor is the conformational shape of the ligand–receptor complex and its consequent effects on dimerization and the modulation of adaptor proteins. The last factor is the differential expression of target tissue adaptor proteins and phosphorylation. A higher concentration of coactivators or corepressors in the target tissue can affect the cellular response of that tissue to the same ligand. Phosphorylation of the receptor by protein kinases increases the transcriptional activity of the receptor.
The Estrogen Receptor Structure and Function
The structure of ER (now known as ERα) was reported in 1986.239 It consists of five components or domains that are divided into six regions, referred to as A-F (Fig. 2-11), instead of the five regions seen in most steroid receptors. The F region is a C-terminal segment of 42 amino acids that influences the conformational changes that occur after estrogen/antiestrogen binding. Thus, it modulates the level of transcriptional activities, most likely by affecting the interaction with coregulator proteins. It has a molecular weight of 66,000 and contains 595 amino acids. ER mRNA is 6.8 kilobases and contains 8 exons derived from a gene located on the long arm of chromosome 6. More recently a second form of ER has been discovered and named ERβ; it is encoded by a gene located on chromosome 14240 and is in close proximity to the genes that are related to Alzheimer’s disease.241 The two receptors show a high degree of homology in the DNA-binding domain (97%) and ligand-binding domain (59%) but less so in hinge (30%), regulatory (17%), and F regions (17.9%)241,242 (see Fig. 2-11). Hence, the binding characteristics of these two receptors are similar, although they differ significantly in their ability to activate gene transcription by regulatory domain TAF-1, which is minimal or absent in ERβ. Both ERα and ERβ are required for normal ovarian function, as shown by specific receptor knockout studies in mice.16 ERα is primarily
The Estrogen Receptors
Nuclear localization
Transcription activation function-1 (TAF-1)
ER-α
NH2
A/B
Ligand binding, heatshock protein binding, transcription activation function-2 (TAF-2)
DNA binding, dimerization
C
E
D
Conformational influence
F
1
Regulatory domain ER-β
COOH 595
NH2
A/B 1
DNA binding domain C
Hinge
D
Hormone binding domain E
F region
F
COOH 485
Figure 2-11 A schematic diagram of two estrogen receptor (ER) isoforms. Different domains (A-F) and their corresponding functions are illustrated. ER-α, estrogen receptor α; ER-β, estrogen receptor β.
35
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Section 1 Basic Science protein kinase phosphorylation, activating the estrogen receptor—even in the absence of estrogen. Somatic mutations in ERα are described and may be associated with certain disease states. A nonsense mutation (premature stop codon) in ERα has been described in a patient with decreased bone mineral density, increased bone turnover, and incomplete closure of bone epiphyses, which demonstrates the role of the ERα in bone growth and homeostasis.246 ER mutations have also been detected in patients with breast cancer. Such mutations include exon 5 deletion within the ligandbinding domain, leading to a constitutively active receptor, and exon 7 deletion, displaying dominant negative activity and inhibition of ER function.247 Antiestrogens and ER
Compounds with antiestrogenic activity can be classified into two categories: those with pure antiestrogenic activity and those with both agonist and antagonist properties. Tamoxifen—an antiestrogen that is used both as a chemopreventive agent and as a hormonal therapeutic agent for breast cancer—inhibits ER action.248 Paradoxically, tamoxifen acts as an estrogen in uterine tissue, and this tissue-specific estrogenic effect is the reason why prolonged tamoxifen therapy increases the risk of uterine cancer.249 Raloxifene, a related benzothiophene analog, retains its antiestrogenic effect in breast and uterine tissue. Both tamoxifen and raloxifene have estrogen-like effects on nonreproductive tissues such as bone and heart and lung tissue.250 Tamoxifen acts by competing with estrogen for receptor binding. Because estrogen-binding affinity is of higher magnitude than tamoxifen, severalfold higher concentrations of tamoxifen are required to inhibit estrogen action. The agonistic or antagonistic effect of tamoxifen is determined by the presence of different promoter elements in the specific cell type.251 Estrogen binding to receptors activates both transcription domains (i.e.,TAF-1 and TAF-2). Tamoxifen’s agonistic activity is due to activation of TAF-1, and its antagonistic activity is due to its ability to inhibit the estrogen-dependent activation of TAF-2. The ligand-binding sites for estrogen and antiestrogen are not identical, and tamoxifen binding on receptors induces conformational changes that alter interaction with estrogen-associated proteins and modulates transcriptional activity.251,252 Tamoxifen also activates ERmediated induction of promoters that are regulated by the
TAF-1 site, which explains why it has estrogenic effects on the endometrium—a tissue with significant TAF-1 transcription function. In other cell types, such as those in the breast, TAF-1 has weak transcriptional activity. Hence, antiestrogens have no effect on TAF-1 mediated transcription.253 Raloxifene, on the other hand, may activate estrogen-responsive genes through a response element that is distinct from HRE.254 Pure antiestrogens are derivatives of estradiol that have a long hydrophobic side chain at position 7. Examples of pure antiestrogens include ICI 164,384 and ICI 182,780 (Fulvestrant). Binding of pure antiestrogens may sterically interfere with the dimerization process and thus inhibit DNA binding. Furthermore, these compounds increase the rate of receptor degradation and also inhibit ER-mediated transcription by preferential binding to corepressors, which contributes to their antiestrogenic activity.255,256 Progesterone Receptor Structure and Function
As with the estrogen receptor, there are two major forms of progesterone receptors— PR-A and PR-B—which are derived from the same gene. PR-A and PR-B are identical except that PR-B contains an additional 164-amino acid sequence at the Nterminal end, which is referred to as the B-upstream segment (BUS) (Fig. 2-12). PR-A has a molecular weight of 94 kDa and contains 768 amino acids; PR-B is 114 kDa with 933 amino acids. The two forms derive from two distinct estrogenregulated promoters.257 The transcription function domain (TAF-1) in the progesterone receptor is located in the 91-amino acid segment of the regulatory region, and TAF-2 is located in the hormone-binding domain. In PR-B, the BUS contains a third activation domain, TAF-3, which can synergize the actions of other TAFs or autonomously activate transcription.258 TAF-3 recruits and allows a separate subset of coactivators to bind with PR-B that do not interact efficiently with PR-A. Thus, PR-A and PR-B display different transactivation properties that are both cell specific and target gene promoter specific.259 The two isoforms PR-A and PR-B have distinct cellular localization and in the absence of ligand binding, PR-A is predominantly localized in the nucleus and PR-B is present in the cytoplasm.260 The role of progesterone receptor isoforms is not yet fully elucidated. Selective ablation of PR-A expression in mice resulted in severe abnormalities in ovarian and uterine function that led to
Nuclear localization
The Progesterone Receptors Transcription activation function-1 (TAF-1)
PR-A
NH2
A/B
DNA binding, dimerization
C
Ligand binding, transcription activation function-2 (TAF-2)
D
E
1
B-upstream segment (BUS) PR-B
NH2
Regulatory domain A/B
1
COOH 769
DNA binding domain C
Hinge
D
Hormone binding domain E
COOH 933
Transcription activation function-3 (TAF-3)
36
Figure 2-12 A schematic diagram of progesterone receptors isoforms. Different domains (A-E) and their corresponding functions are shown. PR-A, progesterone receptor-A; PR-B, progesterone receptor-B.
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Chapter 2 Ovarian Hormones terone, estrogen, glucocorticoid, and mineralocorticoid receptors) but is related most closely to the progesterone receptor.270 Progesterone shows cross-reactivity with androgen receptors, to a degree that becomes clinically relevant only at pharmacologic doses. In most tissues, testosterone is converted to DHT by the action of the enzyme 5α-reductase. DHT binds to the androgen receptor with a higher affinity than testosterone, leading to greater stabilization of the receptor and more efficient signaling, which amplifies the androgen action. Hence, the efficiency of local conversion of testosterone to DHT is an important intracellular step in the androgen response. A large number of androgen receptor mutations that can alter receptor function have also been described271,272; for example inactivating point mutations in the hormone-binding domain of the androgen receptor can generate different phenotypes that lead to partial to complete androgen insensitivity. A point mutation at residue 689 that substitutes Proline to Histidine may alter the conformation of the ligand-binding domain, which reduces the androgen receptor’s affinity for DHT and abolishes its ability to transactivate the HRE.273 A Serine to Proline substitution at residue 865 eliminates androgen binding and transactivation; thus it also causes complete androgen insensitivity.274 At residue 807, a substitution of Threonine for Methionine causes partial androgen insensitivity by reducing—but not abrogating—the androgen binding to the receptor. However, a Valine or Arginine substitution at the same site totally abrogates androgen binding and causes complete androgen insensitivity syndrome.275
infertility but did not affect progesterone responses in the mammary gland or thymus.261 In contrast PR-B ablation does not affect ovarian, uterine, and thymic responses to progesterone and manifests as reduced mammary ductal morphogenesis. Thus, PRA is essential for female fertility; in the absence of PR-A, PR-B functions in a tissue-specific manner and mediates some of the progesterone receptor actions in the mammary gland.261 However, transgenic mice carring an extra copy of the PR-A gene have abnormal mammary gland development, indicating that overexpression of PR-A may have physiologic significance. The relative levels of the two isoforms differ in the endometrium during the menstrual cycle.262 In the uterus, progesterone action downregulates cell-cycle arrest proteins but upregulates growth factors and their receptors and other regulators263 and is also essential for the initiation and maintenance of pregnancy. Progesterone antagonist RU-486 (mifepristone) initially was synthesized as a glucocorticoid receptor antagonist264 but later was found to display marked antiprogesterone activity.265 It binds to the glucocorticoid recptor with threefold higher affinity than dexamethasone and to the progesterone receptor with a fivefold higher affinity than natural progesterone.266 Unlike progesterone, the RU-486–progesterone receptor complex inhibits transcription because it has a slightly different conformational change in the TAF-2 domain.267 If implantation occurs, it downregulates progesterone-induced genes and results in decidual necrosis and detachment of the conception products.251,266 Androgen Receptor Structure and Function
The androgen receptor gene was cloned in 1988 and was localized on the human X chromosome between the centromere and q13.268 Like the progesterone receptor, the androgen receptor also exists in two forms: a full-length B form and a shorter A form (molecular weights ≈110 kDa and 87 kDa); both are encoded by the same gene.269 The 87-kDa isoform (AR-A) contains the intact C-terminus but lacks 188 amino acid residues in the N-terminus of the 110-kDa isoform (AR-B) (Fig. 2-13). The ratio of AR-B to AR-A in genital skin fibroblasts from healthy subjects is 10:1. It is not known whether there are functional differences between these isoforms.269 The DNA-binding domain or TAF-2 of the androgen receptor is similar to the TAF-2 regions of other steroid hormone receptors (proges-
Nongenomic Actions of Steroids Some steroid hormone actions are independent of their classic genomic actions, as mediated via nuclear receptors—these are called nongenomic actions.276 These effects are rapid, occur within seconds, and are not affected by inhibitors of gene transcription such as dactinomycin or inhibitors of protein synthesis such as cycloheximide. These rapid actions include sodium and calcium ion transport and some neural and cardiovascular effects.277 The messenger and effector system vary with the steroid and the cell type. Thus far, studies have suggested that specific binding sites or receptors are present on the cell membrane and that steroid binding triggers rapid changes in the electrolyte transport system.
Nuclear localization
The Androgen Receptors Transcription activation function-1 (TAF-1)
NH2
AR-A
A/B
DNA binding, dimerization
C
D
Ligand binding, transcription activation function-2 (TAF-2)
E
188
B-upstream segment (BUS) AR-B
Regulatory domain A/B
NH2 1(Met)
188 (Met)
COOH 917
DNA binding Hinge domain C
D
Hormone binding domain E
COOH 917
Transcription activation function-3 (TAF-3)
Figure 2-13 A schematic diagram of androgen receptor isoforms. The androgen receptor is very similar to the progesterone receptor and exists in a shorter A form and a full-length B form.
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Section 1 Basic Science For example, estrogens have been shown to modulate some cardiovascular effects by inducing Ca2+ flux and vasodilation in the coronary artery.278 Furthermore, steroids can activate secondmessenger pathways, generating second messengers capable of altering gene transcription independently of their classical receptor-mediated gene transcription.279,280 Thus, steroid hormones have nongenomic effects as well as genomic effects that are mediated by both classical steroid receptor-mediated pathways and second-messenger pathways.
Tropic Hormone Action Tropic hormones (i.e., gonadotropins and GnRH) are primarily hydrophilic and depend on their interactions with receptors scattered on the plasma membrane at the cell surface. These receptors, in turn, can be classified into four groups based on their structural homology and type of intracellular messenger involved in activating the signal transduction pathway (see Table 2-6).
G Protein-Coupled Receptors
38
The gonadotropin and GnRH receptors belong to the large family of receptors that are known as serpentine or seven-transmembrane domain receptors because each contains three domains: an aminoterminal extracellular domain (ectodomain) followed by seven hydrophobic amino acid segments; the transmembrane domains, which span the membrane bilayer (or endodomain); and a hydrophilic carboxyl-terminal domain, which resides within the cytoplasmic compartment. Because they depend on G protein transducers to execute their biologic effects, they are also known as G protein-coupled receptors (GPCRs). G proteins are heterotrimeric proteins associated with these receptors and are socalled because they bind the guanine nucleotides guanosine diphosphate (GDP) and guanosine triphosphate (GTP). Each G protein consists of three subunits: α, β, and γ. They are a heterogeneous family, and at least 16 α subunit genes, 6 β subunit genes, and 12 γ subunit genes have been identified. Various combinations of these provide a large number of possible αβγ complexes. The identity of the individual G protein is determined by the nature of the α subunit. As such, G proteins can be divided into four subfamilies (Gs, Gi, Gq, and Gi2) based on their protein sequence homology. They act as transducers, linking the receptors with the effector proteins that are responsible for producing changes in cellular function. The large variety of G proteins allows for flexibility and diversity in the response of the target cell, depending on the level of G protein expression. There are many types of possible effector molecules, including adenylyl cyclase, calcium channels, potassium channels, cGMP, and phospholipase. Each effector molecule in turn produces a large quantity of second messengers such as cAMP, Ca2+, and phosphatidylinositols, which activate an even larger number of downstream molecules. This is an important factor that explains why the endocrine system is sensitive to such low concentrations of circulating ligand and why only a small percentage of cell membrane receptors need to be occupied to generate a response. Other examples of receptors and their ligands that fall into this family include the TSH receptor and ACTH receptor. The structure of the LH receptor and FSH receptor are similar to each other and show close homology with the TSH receptor. A comparison of the LH receptor with the FSH receptor shows
about 70% homology in the transmembrane domain, but only 42% in the ectodomain and 48% in the endodomain regions. Gonadotropin Receptors
The gonadotropin receptors are primarily expressed in the gonadal tissues and demonstrate a unique expression pattern that determines their cell-specific roles. LH receptors are present in ovarian thecal and luteal cells and in testicular Leydig cells. FSH receptors are found in ovarian granulosa cells and in testicular Sertoli cells. Furthermore, FSH induces LH receptors in the granulosa cells that are expressed in mature follicles. These receptors are essential in mediating the gonadotropin actions in steroidogenesis and in gonadal growth and differentiation. Their structure, function, and regulation as well as molecular biology have been extensively covered in recent reviews.281,282 Structure and Function
Genes for both LH and FSH receptors are located on chromosome 2p21. The LH receptor gene is about 70 kb and consists of 11 exons and 10 intervening introns.281 The FSH receptor gene is about 54 kb and contains 10 exons and 9 intervening introns.282 As shown in Figure 2-14, the structural similarities between the two receptors are remarkable with the exception of an additional exon in the LH receptor. The long exon 11 in LH receptor and exon 10 in FSH receptor encodes for the seven-transmembrane domains and the intracellular tail as well as the C-terminal end of the hinge region of ectodomain. The remaining 9 exons in the FSH receptor and 10 exons in the LH receptor encode for the entire ectodomain. Both receptors have multiple splice sites, leading to transcription of multiple mRNA splice variants and expression in the ovary and testis.281 The LH receptor protein contains a 24-amino acid signal peptide (17 in FSH receptor) and the mature protein consists of 675 amino acid residues (678 in FSH receptor) (see Fig. 2-14). The molecular mass is approximately 85 to 90 kDa for both glycosylated LH and FSH receptor proteins. The ectodomains of these receptors are composed of several leucine-rich repeats (LRRs) of about 24 amino acid residues each (9 in LH receptor and 10 in FSH receptor) that form a half donut-shaped structure and are essential for the binding of gonadotropins. The ectodomain is connected to the transmembrane region by the hinge region with conserved sequences. The transmembrane region consists of seven helical structures and is followed by the cytoplasmic C-terminal tail, both of which are important for interaction with intracellular proteins. The binding of LH and FSH to their specific receptors leads to receptor activation and downstream signaling. Mechanism of Action
The intracellular messenger for LH and FSH is cAMP, which is derived from adenosine triphosphate (ATP) through the action of the enzyme adenylate cyclase. The basic steps involved in the receptor-mediated action of gonadotropins are illustrated in Figure 2-15. The regulation of adenylate cyclase is mediated by a GTP-dependent regulatory G-protein, each of which is composed of three subunits—α, β, and γ—and is associated with the receptor in an inactive GDP-bound form. Gonadotropic binding to their respective receptors induces a conformational change
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Chapter 2 Ovarian Hormones
A
FSH receptor mutations FSH receptor gene:
1
FSH receptor protein: NH2
2
3
1
4
5
6
7
8
9
10 TM
Ectodomain
Intracellular domain
Ile 160 Thr Ala 189 Val / Asn 191 Ile Inactivating mutation:
675
COOH
Asp 224 Val Pro 346 Arg/ Ala 419 Thr Arg 573 Cys/ Leu 601 Val Asp 567 Gly
Activating mutation:
B
LH receptor mutations LH receptor gene:
1
LH receptor protein: NH2
2 1
3
4
5
6
7
8
9
10
11 TM
Ectodomain
Intracellular domain
Cys 131 Arg Phe 194 Val Inactivating mutation:
678
Deletion of exons 8 and 10
COOH
Cys 343 Ser / Glu 354 Lys / Ile 374 Thr / Thr 392 Ile / Trp 491 Stp / Cys 543 Arg / Cys 545 Stp / Arg 554 Stp / Ala 593 Pro / ΔLeu 608 /Val 609 / Ser 616 Tyr / Ile 625 Lys Activating mutation:
Leu 368 Pro / Ala 373 Val /Met 398 Thr / Leu 457 Arg / Ile 542 Leu / Asp 564 Gly / Ala 568 Val / Met 571 Ile / Ala 572 Val / Ile 575 Leu / Thr 577 Ile / Asp 578 Tyr / Cys 581 Arg
Figure 2-14 A schematic representation of the FSH (A)/LH (B) receptor gene and localization of identified mutations. The structural organization of the FSH/LH receptor protein is provided below it. The extracellular domain of the protein is shown as a straight line, followed by the seven-transmembrane domains and the intracellular domain. In the FSH receptor gene exon 10 and in the LH receptor gene exon 11 codes for the seven-transmembrane signal transduction domains.
in the receptor and activation of the G-protein complex that leads to release of GDP and binding of the α subunit to GTP.283 Subsequently, the GTP-bound form of the α subunit disassociates from the receptor as well as from the stable β/γ dimer and activates the adenylate cyclase. This in turn leads to an increase in the levels of intracellular cAMP, which in turn activates protein kinase A (PKA) by binding to the inhibitory regulatory subunit of PKA and causing it to dissociate from the complex. Activated PKA phosphorylates many cellular substrates, including several nuclear transcription factors (e.g., cAMP response binding protein [CREB]).281 The binding of CREB to the cAMP response element activates many genes. The fact that PKA activation does not account for all the actions of gonadotropins and that LH can stimulate steroid hormone synthesis without significant changes in cAMP indicated that another pathway may be activated. There is now evidence that the phosphatidylinositol 3,4,5-triphosphate (IP3) pathway is also activated by the LH receptor284 as well as by the FSH receptor,285 although it is not clear whether the IP3 pathway activates the same or different responses in the target
cells. The third signaling pathway, the MAPK pathway, has also been shown to be activated by the LH receptor286 (see Fig. 2-15). Continuous stimulation of receptors can lead to a decrease in response, a phenomenon known as downregulation. For example, pulsatile LH secretion maintains LH receptors and steroidogenesis in the gonads. However, persistent endogenous elevation of LH or hCG levels downregulates LH receptors and leads to desensitization to the hormonal signal.287 This involves receptor phosphorylation, which uncouples the receptor from the G protein, ending the response. The LH/hCG receptor undergoes desensitization in response to LH or hCG by the phosphorylation of the C-terminal cytoplasmic tail of the receptor.288 Another mechanism of downregulation is the uncoupling of the regulatory and catalytic subunits of the adenylate cyclase enzymes. For example, LH stimulates steroidogenesis by coupling the stimulatory to the catalytic units of adenylate cyclase. Prostaglandin F2α, on the other hand, inhibits the action of LH by an inhibitory regulatory unit that uncouples the catalytic unit to interfere with gonadotropin action.
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FSH/LH receptor Adenylate cyclase
Insulin receptor
Cell membrane RAS Gβγ
P Shp-2
P
Gα
Grb-2
IRS
SOS
Gα
ATP
GTP RAF
GDP
cAMP P13K MAPK
P
Protein translation
PKA
P13K IRS
ERK
PIP2
IP3
PDK-1 AKT/P
KB
Gene response Activation of transcription factors Nucleus
Figure 2-15 A diagrammatic representation of the interlinked signaling pathways between FSH/LH G-protein coupled receptors (GPCRs) and insulin/IGF-I receptor tyrosine kinases in ovarian cells. Activation of GPCR by hormone binding stimulates the Gα subunit to bind guanosine triphosphate (GTP) instead of guanosine diphosphate (GDP), leading to its dissociation from β/γ subunits to activate downstream signaling factors such as adenylyl cyclase that synthesizes second-messenger cyclic adenosine monophosphate (cAMP). Binding of cAMP in turn activates protein kinase A (PKA), leading to DNA binding and downstream cellular response. Also illustrated here is the IGF-I receptor signaling pathway. IGF-I/Insulin binding to the receptor initiates autophosphorylation and tyrosine phosphorylation of insulin receptor substrates (IRS), leading to activation of phosphatidylinositol-3-kinase (PI3K) and generation of 3-phosphorylated-inositol (IP3) from phosphoinositol (PIP2), which activates PI-dependent protein kinase-1 (PDK-1). PDK-1 in turn activates Akt/protein kinase B (Akt/PKB), leading to biologic effects. The activation of the insulin receptor substrates (IRS) also allows the docking and activation of small adaptor molecules with SH-2 domains (e.g., growth factor receptor binding protein-2 [Grb-2[] and Shp2). Activated Grb-2 recruits SOS-1, which activates the RAS pathway and gene transcription. (Main pathways are in bold, interlinked signaling pathways are in broken lines). SOS-1, son-ofsevenless; ERK, extracellular signal regulated kinase; FSH, follicle stimulating hormone; LH, luteinizing hormone.
Mutations in Gonadotropin Receptors
40
Both activating and inactivating gene mutations have been described in LH and FSH receptors and have been the subject of recent review.209 Interestingly, the activating mutations in the LH receptor gene result in altered testosterone production, and these mutations are known to affect the phenotype of men only, whereas inactivating mutations affect sexual differentiation and fertility in both men and women. To date, a total of 15 activating mutations have been identified in the LH receptor, all localized in the transmembrane region or in the intracellular loops (see Fig. 2-14A). Transmembrane 6 and the third intracellular loop are recognized as mutational hot spots, and 10 of 14 mutations are localized to these regions. These gain-of-function mutations lead to male-limited precocious puberty characterized by Leydig cell hyperplasia, premature puberty, and onset of spermatogenesis in boys as young as age 3 years.289,290 These patients have blood testosterone levels in the pubertal range, with low or undetectable LH
levels. A novel activating LH receptor mutation associated with Leydig cell tumors and nonfamilial precocious puberty has also been described.291 An equal number of inactivating mutations in LHR that cause partial to complete inactivation of receptor have been described.209 These inactivating mutations in LH receptors cause Leydig cell hypoplasia in men and amenorrhea in women. In contrast, lossof-function mutations are scattered throughout the LH receptor protein. Depending on the mutation, the severity of the male phenotype varies from primary hypogonadism to male pseudohermaphroditism with sexual ambiguity. Conversely, activating mutations of the FSH receptor are rare. Only one mutation has been identified this far (located in the third intracellular domain of exon 10) in a hypophysectomized patient who was fertile despite the lack of FSH and LH production.292 Likewise, fewer inactivating mutations have been identified in the FSH receptor (see Fig. 2-14B). Most of these are located in the extracellular domain and show reduced ligand
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Chapter 2 Ovarian Hormones binding and signal transduction. They are implicated in hypergonadotropic ovarian dysgenesis in females and variable degrees of spermatogenic failure in males. Recently, two heterozygous missense mutations in the exon 10 encoding the transmembrane region have been described, and both were associated with the familial spontaneous ovarian hyperstimulation syndrome. Although there were no significant differences in the cAMP responses between the wild-type and mutated receptor, the mutated receptor gained sensitivity to hCG.293,294 Low-affinity binding of hCG to the FSH receptor most likely triggered signal transduction that led to hyperstimulation of ovaries.
Ligand
Gq-coupled receptor Cell membrane GDP Gq
Activating mutation: Arg 262 Gln / Tyr 284 Cys GnRH receptor gene: 5' UTR GnRH receptor protein:
Activating mutation:
NH2
1 1
2
3
329
Asn 10 Lys / Thr 32 Ile / Gln 106 Arg Glu 90 Lys / Ala 129 Asp / Arg 139 His
Inactivating mutation:
Ser 168 Asp / Cys 200 Tyr / Ser 217 Arg Leu 266 Arg / Cys 279 Tyr / Leu 314 X
Figure 2-16 A schematic representation of the gonadotropin-releasing hormone (GnRH) receptor gene and localization of identified mutations. The structural organization of the GnRH receptor protein is provided below it. The short extracellular domain of the protein is indicated by the straight line, followed by the seven-transmembrane domains. The GnRH receptor lacks a carboxyterminal cytoplasmic tail. Exon 1 codes for transmembrane domains 1-3, exon 2 codes for transmembrane domains 4-5, and exon 3 codes for transmembrane domains 6-7. 5′UTR, 5′’ untranslated region.
GTP Gq
PIP2
DAG
GTP GDP
Ca2+
Gonadotropin-releasing Hormone (GnRH) Receptor GnRH binds
to specific membrane receptors in pituitary gonadotrophs and stimulates LH and FSH secretion (Fig. 2-16). Besides gonadotrophs, GnRH receptors have also been expressed on the gonads, placenta, and brain295–297 Specific GnRH receptors are also characterized in immortalized αT3-1 gonadotroph cells as well as in GnRH-secreting GT1 hypothalamic cells.296,298 In the ovary, GnRH receptors are expressed in granulosa and luteal cells. In the testis, these receptors are expressed in Leydig cells but not Sertoli cells.299 In cultured granulosa cells, the receptor activation stimulates progesterone and prostaglandin synthesis, oocyte maturation, and ovulation300,301 but inhibits FSHinduced steroidogenesis, follicular development, and maturation as well as inhibin secretion.302–304 In luteal cells, it inhibits LH receptor expression and thus LH action.305 The structure function and intracellular signaling pathways involved in GnRH action have been extensively reviewed in recent years.306–308 The GnRH receptor gene, located on chromosome 4q21.2, consists of three exons309 and encodes a
PLC
IP3 ER
PKC
Ca2+channel Ca2+
Nucleus
Figure 2-17 A schematic representation of GnRH signaling through GPCR. Binding of GnRH to its receptor acts through Gq protein. Activated Gq binds ATP and activates its downstream target phospholipase C (PLC) and hydrolyzes PIP2, producing IP3 and diacylglycerol (DAG). IP3 diffuses through the cytoplasm to the endoplasmic reticulum (ER) and opens a calcium channel releasing calcium stores. Calcium and DAG activate protein kinase C (PKC), leading to cellular response.
327-amino acid protein with an approximate molecular weight of 50 to 60 kDa. The receptor has the characteristic features of GPCRs (Fig. 2-17). It consists of an aminoterminal domain, followed by seven transmembrane domains that are connected by three extracellular and three intracellular loops. Unlike other GPCRs, the GnRH receptor lacks the characteristic C-terminal cytoplasmic domain. GnRH binds to the transmembrane domain and the extracellular loop in the hairpin structure and requires partial entry of its N- and C-terminal regions into the transmembrane core of the receptor.310 The nature of the intracellular signaling mechanism by the GnRH receptor has been primarily studied in a gonadotrophderived αT3-1 cell line, as depicted in Figure 2-18. The effector system in the GnRH receptor is the phospholipase C β (PLCβ) and the second messengers are IP3 and 1,2 diacylglycerol (DAG). Its mechanism of action is dependent on calcium. Activation of the receptor by ligand binding initiates a series of steps that lead to transduction of signals. The first step is G protein (Gq/11)mediated activation of enzyme PLCβ, leading to hydrolysis of phosphoinositides (PIP2) and resulting in the production of IP3 and DAG. The IP3 interacts with a receptor on the endoplasmic reticulum to promote the oscillatory or biphasic release of Ca2+ from intracellular stores, which is known to be an important trigger for gonadotropin secretion. The increased Ca2+ and DAG in turn activate a series of protein kinase C subspecies (PKC). PKC then induce various downstream signal transduction cascades, including the extracellular signal regulated kinase and Jun N-terminal kinase signaling pathways.
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Section 1 Basic Science Ligand Type 1 receptor
Type 2 receptor
factors interact and complement the FSH/LH pathway to control follicular growth. Family of Receptors with Tyrosine Kinase Activity
Cell membrane P R-SMAD R-SMAD
P
Co-SMAD
brane ar mem Nucle DNA-binding partner
P
R-SMAD Co-SMAD
P
Target gene
R-SMAD Co-SMAD
Figure 2-18 The TGF-β/activin signaling pathway. Binding of a TGF-β family member (e.g., activin) to its type 2 receptor forms a ligand–receptor complex and activation of the type 1 receptor by phosphorylation. The activated type 1 receptor then phosphorylates receptor-regulated SMAD (R-SMAD). This allows R-SMAD to associate with Co-SMAD and move into the nucleus. In the nucleus, the SMAD complex associates with a DNA-binding partner, such as FAST-1. This complex then binds to specific enhancers in the target gene, activating gene transcription. (In the TGF-β/activin pathway, R-SMAD is formed by SMAD2 and SMAD3. Co-SMAD is formed from SMAD4.)
Mutations in GnRH Receptor Gene
A functional GnRH receptor is a prerequisite for normal LH and FSH production. Hence, it is critical for normal pubertal development and reproduction. Several inactivating mutations have been identified in the GnRH receptor gene that are associated with variable phenotypes ranging from modest to complete insensitivity to GnRH. These mutations are present in a number of patients with idiopathic hypogonadotropic hypogonadism (IHH) with an autosomal recessive pattern of inheritance as well as in some patients with sporadic IHH.311 Most identified mutations are heterozygous missense mutations and are scattered throughout the GnRH receptor gene. A total of 14 mutations have been identified to date308 and are listed in Figure 2-16. In vitro studies have shown that some of these mutations make the receptor totally nonfunctional; others have some ability to elicit a response to GnRH.
Peptide Hormone/Growth Factor Action
42
Pituitary gonadotropin signaling plays a key role in follicular growth, ovulation, and luteinization. However, it is increasingly recognized that their actions are also dependent on their interaction with peptide/growth factor signaling pathways, including IGFs, EGF, and members of the TGFβ family (see Fig. 2-15). Understanding these pathways provides insight into how these
Insulin, IGF, and EGF receptors belong to a distinct group of receptors and differ from the GPCRs both structurally and functionally. Unlike the GPCRs, they only span the membrane once and acquire their signaling ability through the activation of tyrosine kinase, which is intrinsic to these individual receptor molecules. Hence, they are known commonly as tyrosine kinases. Their main ligands include hormones such as insulin and IGF, as well as paracrine and autocrine regulators such as platelet-derived growth factor (PDGF), bFGF, and EGF. Thus, via tyrosine phosphorylation, a number of physiologic processes such as cell proliferation, cell migration, cell differentiation, and apoptosis are mediated by these receptors. This explains why this group of receptors has been the target of much oncogenic research. All tyrosine kinase receptors have a similar structure: an extracellular domain for ligand binding, a single transmembrane domain, and a cytoplasmic domain. Ligand specificity is determined by the unique amino acid sequences making up the extracellular domain, which determines the three-dimensional conformation of the receptor. The transmembrane domains are heterogeneous, whereas the cytoplasmic domains are fairly homologous. They respond to ligand binding by undergoing conformational changes and autophosphorylation. The structure of the IGF-I receptor is strikingly similar to that of the insulin receptor, with two transmembrane domains linked by disulfide bridges, formed by two α and β subunits.312 The IGF-I receptor gene is located on chromosome 15 at bands q25-26 and contains 21 exons.313 The steps involved in signal transduction by IGF-I/insulin have been extensively reviewed in recent years314,315 and are illustrated in Figure 2-15. The association of the ligand (e.g., insulin) with the receptor’s extracellular domain triggers receptor dimerization. This results in the phosphorylation of tyrosine residues on both the receptor and nonreceptor substrates. The phosphorylation of receptor tyrosine residues occurs at specific locations, which causes these sites to associate with a variety of accessory proteins that have independent signaling capabilities. These accessory proteins include phospholipase Cγ, PI3 kinase (PI3K), GAP, and growth factor receptor-bound protein-2 (GRB2). These interactions are mediated by the presence of highly conserved type 2 src homology domains (SH2) in each accessory molecule, thus named based on their sequence homology to the src protooncogene. Each SH2 domain is specific for the amino acids surrounding the phosphotyrosine residues in the receptor molecule. PI3K also produces a second messenger, such as IP3, which in turn activates kinase AKT, also known as protein kinase B (PKB). Proteins phosphorylated by PKB promote cell survival. Although these associations may trigger immediate signaling events, other accessory proteins (e.g., GRB2) may serve to construct the scaffolding for a more complex signaling apparatus, such as that seen in the RAS-RAF-MEK pathway, This pathway recruits multiple other proteins, resulting in the activation of nuclear transcription and protein synthesis (see Fig. 2-15). Growth hormone and prolactin fall into another group of receptors that also have a single transmembrane-spanning segment and a short cytoplasmic tail. However unlike IGF-I/insulin receptors they do not possess intrinsic tyrosine kinase activity
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Chapter 2 Ovarian Hormones but interact with other soluble transducer molecules (e.g., Janus kinase 2) that do have tyrosine kinase activity. Mechanism of Action of Activins and Inhibins
Activins and inhibins are members of the TGFβ superfamily and use a common general mechanism for signal transduction through serine/threonine-specific protein kinases rather than tyrosine kinases. The mechanisms involved in signal transduction by the serine/threonine kinases has been extensively reviewed in recent years.316,317 The activin receptor was first to be cloned and was later followed by other receptors.318,319 They are glycoproteins of approximately 55 kDa and consist of a 500-amino acid sequence. Two types of activin membrane receptors have been identified: type I (ActR-I) and type II receptors (ActR-II). Each contains an intracytoplasmic serine/threonine kinase domain. The steps involved in the mechanism of action of activin are depicted in Figure 2-18. Activin directly interacts with and binds to the relatively short extracellular region of ActR-II when expressed alone or in concert with ActR-I. It can also bind to other TGFβ family members (e.g., bone morphogenic proteins [BMPs] 2, 4, and 7) in concert with BMP type I receptor, which suggests that these receptors have the ability to cross-talk. Activin binding brings together two type II receptors and two type I receptors, which form a receptor complex. One of the receptor kinases phosphorylates and activates the other, which in turn phosphorylates their substrates—the SMAD proteins [the term SMAD is derived from the combination of names of two genes, the C. elegans gene called Sma and the Drosiphila gene Mad]. SMADs are a novel family of signal transducers that can be divided into three groups that include receptor-regulated SMADs (R-SMAD) and a single common SMAD (C-SMAD or SMAD4). The third group includes inhibitory SMADS that antagonize signaling. In activin/TGFβ signaling, the activated type I receptor phosphorylates ligandspecific R-SMADs (SMAD2 and SMAD3), allowing these proteins to associate with SMAD4. The complex then translocates to the nucleus as transcription cofactor. In the nucleus, the action of SMAD complex is modulated by a variety of transcription factors (DNA-binding proteins) at target DNA promoters, which leads to gene transcription. Inhibin is a heterodimer formed between an inhibin α chain and an activin β chain, and its biologic activity is opposite that of activin. A separate receptor for inhibin has not been identified. The mechanisms by which inhibin antagonizes activin actions are not clearly understood. It has been shown that inhibin competes with activin for binding to the activin receptors but is unable to trigger signaling.320 This may be one of the mechanisms by which inhibins antagonize activin actions. Other actions of inhibin may be mediated by as-yet unidentified inhibin receptors.
such as cytodifferentiation, mitogenesis, and apoptosis in a variety of ways. They act in concert with LH/FSH via a complex network of intracellular signaling to mediate their actions. A functional hypothalamic-pituitary axis is essential for ovarian hormone production. GnRH secretion in a synchronized pulsatile fashion is a key feature in the control of LH/FSH secretion, and new insights have made it a prime drug target for the treatment of infertility. Both GnRH and gonadotropin actions are transmitted through G protein-coupled receptors to target cells via multiple signaling mechanisms. Several mutations and polymorphisms have been identified in their genes and their receptors. These mutations have deleterious effect on reproduction. Although rare, this study has allowed a better understanding of receptor structure and function relationships and helped clarify the molecular pathogenesis of conditions associated with altered gonadotropin secretion and actions. Steroid hormones play a central role in the reproductive system. Physiologic effects of steroid hormones are mediated via their nuclear receptors, which belong to a superfamily of liganddependent transcription factors. The two isoforms of ER and the progesterone receptor are differentially expressed in different tissues, leading to tissue-specific responses. Furthermore, the differences in gene expression depend on interactions with protein cofactors, the coactivators and corepressors. A better understanding of the effect that the cell environment has on nuclear receptors and their coregulators led to the discovery and understanding of the mechanism of action of antiestrogens and selective receptor modulators.
PEARLS ●
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●
SUMMARY ●
The ovary is a dynamic endocrine organ. The follicle cells interact in a highly integrated manner to produce several steroid and peptide hormones. Steroidogenesis requires effective delivery, uptake, and use of sterol by an array of steroidogenic enzymes. Virtually all steps in steroid biosynthesis require the action of LH and FSH and are influenced by endocrine, autocrine, and paracrine actions of several intraovarian peptide hormones, growth factors, cytokines, and neuropeptides. In recent years, research has shown that these growth factors affect various cell processes,
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There is a specific cellular location for many steroidogenic enzymes. Sex steroids can be produced thtough two pathways: Δ5(the 3β-hydroxysteroid pathway) or Δ4 (the 3-ketone pathway). Hydroxylases and aromatase enzymes belong to the cytochrome P450 family. The two-cell theory explains the production of steroid hormones of the ovary. Thecal cells respond to LH; granulosa cells respond to both FSH and LH. Theca cells produce androgens that are aromatized by the granulosa cells to estrogens. Estradiol is the main estrogen in premenopausal women. Progesterone and 17 OH-progesterone are produced mainly by the corpus luteum in the luteal phase. The majority of testosterone is derived from the peripheral metabolism of DHEA and androstenedione. Very little ovarian steroid hormone circulates free in the circulation but rather is bound to proteins. Inhibin A and B are heterodimers produced by the granulosa cells. Inhibin B is highest during the luteal–follicular transition and early follicular phase. Inhibin A rises in the luteal phase. Inhibin A is produced primarily by the fetoplacental unit during pregnancy. Activins are dimers of the inhibin β subunit and are produced by the granulosa cells. Follistatin is produced by the granulosa cells and acts mostly as as an antagonist of activin.
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Steroid hormones bind to intracellular receptors located within the cytoplasm or nucleus.
●
Polypeptide hormones and growth factors interact with cellsurface receptors located on the plasma membrane.
REFERENCES
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virilization but underdeveloped testicles with azoospermia, low FSH but high lutropin and normal serum testosterone concentrations. Clin Chem Lab Med 36:663–665, 1998. Midgley AR Jr: Radioimmunoassay: A method for human chorionic gonadotropin and human luteinizing hormone. Endocrinology 79:10–18, 1966. Faiman C, Ryan RJ: Radioimmunoassay for human follicle stimulating hormone. J Clin Endocrinol Metab 27:444–447, 1967. Faiman C, Ryan RJ: Radioimmunoassay for human luteinizing hormone. Proc Soc Exp Biol Med 125:1130–1133, 1967. Halvorson LM: Gonadotropic hormones: Biosynthesis, secretion, receptors and action. In Yen SSC, Barberi RL (eds): Reproductive Endocrinology. Philadelphia, WB Saunders, 1999, p 89. Jaakkola T, et al: The ratios of serum bioactive/immunoreactive luteinizing hormone and follicle-stimulating hormone in various clinical conditions with increased and decreased gonadotropin secretion: Reevaluation by a highly sensitive immunometric assay. J Clin Endocrinol Metab 70:1496–1505, 1990. Van Damme MP, Robertson DM, Diczfalusy E: An improved in vitro bioassay method for measuring luteinizing hormone (LH) activity using mouse Leydig cell preparations. Acta Endocrinol (Copenh) 77:655–671, 1974. Wang C: Bioassays of follicle stimulating hormone. Endocr Rev 9:374–377, 1988. Chappel S: Biological to immunological ratios: Reevaluation of a concept. J Clin Endocrinol Metab 70:1494–1495, 1990. Rebar RW, Connolly HV: Clinical features of young women with hypergonadotropic amenorrhea. Fertil Steril 53:804–810, 1990. Yen SS, et al: Hypothalamic amenorrhea and hypogonadotropinism: Responses to synthetic LRF. J Clin Endocrinol Metab 36:811–816, 1973. Heffner LJ, Gramates LS, Yuan RW: A glycosylated prolactin species is covalently bound to immunoglobulin in human amniotic fluid. Biochem Biophys Res Commun 165:299–305, 1989. Farkouh NH, Packer MG, Frantz AG: Large molecular size prolactin with reduced receptor activity in human serum: High proportion in basal state and reduction after thyrotropin-releasing hormone. J Clin Endocrinol Metab 48:1026–1032, 1979. Markoff E, et al: Glycosylation selectively alters the biological activity of prolactin. Endocrinology 123:1303–1306, 1988. Vieira JG, et al: Extensive experience and validation of polyethylene glycol precipitation as a screening method for macroprolactinemia. Clin Chem 44:1758–1789, 1998. Evans RM: The steroid and thyroid hormone receptor superfamily. Science 240:889–895, 1988. McKenna NJ, Lanz RB, O’Malley BW: Nuclear receptor coregulators: Cellular and molecular biology. Endocr Rev 20:321–344, 1999. Jensen EV, et al: Receptors reconsidered: A 20-year perspective. Recent Prog Horm Res 38:1–40, 1982. Tsai MJ, O’Malley BW: Molecular mechanisms of action of steroid/ thyroid receptor superfamily members. Annu Rev Biochem 63:451–486, 1994. King WJ, Greene GL: Monoclonal antibodies localize oestrogen receptor in the nuclei of target cells. Nature 307:745–747, 1984. Bresnick EH, et al: Evidence that the 90-kDa heat shock protein is necessary for the steroid binding conformation of the L cell glucocorticoid receptor. J Biol Chem 264:4992–4997, 1989. Strahle U, Klock G, Schutz G: A DNA sequence of 15 base pairs is sufficient to mediate both glucocorticoid and progesterone induction of gene expression. Proc Natl Acad Sci USA 84:7871–7855, 1987. Klock G, Strahle U, Schutz G: Oestrogen and glucocorticoid responsive elements are closely related but distinct. Nature 329:734–736, 1987. Arriza JL, et al: Cloning of human mineralocorticoid receptor complementary DNA: Structural and functional kinship with the glucocorticoid receptor. Science 237:268–275, 1987. Edwards DP: The role of coactivators and corepressors in the biology and mechanism of action of steroid hormone receptors. J Mammary Gland Biol Neoplasia 5:307–324, 2000.
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Chapter 2 Ovarian Hormones 239. Green S, et al: Cloning of the human oestrogen receptor cDNA. J Steroid Biochem 24:77–83, 1986. 240. Kuiper GG, et al: Cloning of a novel receptor expressed in rat prostate and ovary. Proc Natl Acad Sci USA 93:5925–5930, 1996. 241. Enmark E, et al: Human estrogen receptor β—gene structure, chromosomal localization, and expression pattern. J Clin Endocrinol Metab 82:4258–4265, 1997. 242. Mosselman S, Polman J, Dijkema R: ER β: Identification and characterization of a novel human estrogen receptor. FEBS Lett 392:49–53, 1996. 243. Brzozowski AM, et al: Molecular basis of agonism and antagonism in the oestrogen receptor. Nature 389:753–758, 1997. 244. Pike AC, et al: Structure of the ligand-binding domain of oestrogen receptor β in the presence of a partial agonist and a full antagonist. Embo J 18:4608–4618, 1999. 245. Kuiper GG, et al: Comparison of the ligand binding specificity and transcript tissue distribution of estrogen receptors α and β. Endocrinology 138: 863–870, 1997. 246. Smith EP, et al: Estrogen resistance caused by a mutation in the estrogen-receptor gene in a man. NEJM 331:1056–1061, 1994. 247. Fuqua SA, et al: Variant human breast tumor estrogen receptor with constitutive transcriptional activity. Cancer Res 51:105–109, 1991. 248. Grainger DJ, Metcalfe JC: Tamoxifen: Teaching an old drug new tricks? Nat Med 2:381–385, 1996. 249. Kedar RP, et al: Effects of tamoxifen on uterus and ovaries of postmenopausal women in a randomised breast cancer prevention trial. Lancet 343:1318–1321, 1994. 250. Yang NN, et al: Estrogen and raloxifene stimulate transforming growth factor-β 3 gene expression in rat bone: A potential mechanism for estrogen- or raloxifene-mediated bone maintenance. Endocrinology 137:2075–2084, 1996. 251. Berry M, Metzger D, Chambon P: Role of the two activating domains of the oestrogen receptor in the cell-type and promoter-context dependent agonistic activity of the anti-oestrogen 4-hydroxytamoxifen. Embo J 9:2811–2818, 1990. 252. Landel CC, Kushner PJ, Greene GL: The interaction of human estrogen receptor with DNA is modulated by receptor-associated proteins. Mol Endocrinol 8:1407–1419, 1994. 253. Webb P, et al: Tamoxifen activation of the estrogen receptor/AP-1 pathway: Potential origin for the cell-specific estrogen-like effects of antiestrogens. Mol Endocrinol 9:443–456, 1995. 254. Yang NN, et al: Identification of an estrogen response element activated by metabolites of 17β-estradiol and raloxifene. Science 273:1222–1225, 1996. 255. Osborne CK, et al: Double-blind, randomized trial comparing the efficacy and tolerability of fulvestrant versus anastrozole in postmenopausal women with advanced breast cancer progressing on prior endocrine therapy: Results of a North American trial. J Clin Oncol 20:3386–3395, 2002. 256. Bundred N, Howell A: Fulvestrant (Faslodex): Current status in the therapy of breast cancer. Expert Rev Anticancer Ther 2:151–160, 2002. 257. Kastner P, et al: Two distinct estrogen-regulated promoters generate transcripts encoding the two functionally different human progesterone receptor forms A and B. Embo J 9:1603–1614, 1990. 258. Sartorius CA, et al: A third transactivation function (AF3) of human progesterone receptors located in the unique N-terminal segment of the B-isoform. Mol Endocrinol 8:1347–1360, 1994. 259. Giangrande PH, et al: The opposing transcriptional activities of the two isoforms of the human progesterone receptor are due to differential cofactor binding. Mol Cell Biol 20:3102–3115, 2000. 260. Lim CS, et al: Differential localization and activity of the A- and Bforms of the human progesterone receptor using green fluorescent protein chimeras. Mol Endocrinol 13:366–375, 1999. 261. Conneely OM, et al: Reproductive functions of progesterone receptors. Recent Prog Horm Res 57:339–355, 2002. 262. Feil PD, Clarke CL, Satyaswaroop PG: Progestin-mediated changes in progesterone receptor forms in the normal human endometrium. Endocrinology 123:2506–2513, 1988.
263. Ogle TF: Progesterone action in the decidual mesometrium of pregnancy. Steroids 67:1–14, 2002. 264. Moguilewsky M, Philibert D: RU 38486: Potent antiglucocorticoid activity correlated with strong binding to the cytosolic glucocorticoid receptor followed by an impaired activation. J Steroid Biochem 20:271–276, 1984. 265. Baulieu EE: Contragestion and other clinical applications of RU 486, an antiprogesterone at the receptor. Science 245:1351–1357, 1989. 266. Spitz IM, Bardin CW: Mifepristone (RU 486)—a modulator of progestin and glucocorticoid action. NEJM 329:404–412, 1993. 267. Gronemeyer H, et al: Mechanisms of antihormone action. J Steroid Biochem Mol Biol 41:217–221, 1992. 268. Lubahn DB, et al: Cloning of human androgen receptor complementary DNA and localization to the X chromosome. Science 240:327–330, 1988. 269. Wilson CM, McPhaul MJ: A and B forms of the androgen receptor are present in human genital skin fibroblasts. Proc Natl Acad Sci USA 91:1234–1238, 1994. 270. Jenster G, et al: Functional domains of the human androgen receptor. J Steroid Biochem Mol Biol 41:671–675, 1992. 271. Brinkmann AO: Molecular basis of androgen insensitivity. Mol Cell Endocrinol 179:105–109, 2001. 272. Chavez B, et al: Eight novel mutations of the androgen receptor gene in patients with androgen insensitivity syndrome. J Hum Genet 46:560–565, 2001. 273. Rosa S, et al: Complete androgen insensitivity syndrome caused by a novel mutation in the ligand-binding domain of the androgen receptor: Functional characterization. J Clin Endocrinol Metab 87:4378–4382, 2002. 274. Mongan NP, et al: Two de novo mutations in the AR gene cause the complete androgen insensitivity syndrome in a pair of monozygotic twins. J Clin Endocrinol Metab 87:1057–1061, 2002. 275. Ong YC, Kolatkar PR, Yong EL: Androgen receptor mutations causing human androgen insensitivity syndromes show a key role of residue M807 in Helix 8–Helix 10 interactions and in receptor ligand-binding domain stability. Mol Hum Reprod 8:101–108, 2002. 276. Revelli A, Massobrio M, Tesarik J: Nongenomic actions of steroid hormones in reproductive tissues. Endocr Rev 19:3–17, 1998. 277. Revelli A, Tesarik J, Massobrio M: Nongenomic effects of neurosteroids. Gynecol Endocrinol 12:61–67, 1998. 278. Chester AH, et al: Oestrogen relaxes human epicardial coronary arteries through nonendothelium-dependent mechanisms. Coron Artery Dis 6:417–422, 1995. 279. Aronica SM, Kraus WL, Katzenellenbogen BS: Estrogen action via the cAMP signaling pathway: Stimulation of adenylate cyclase and cAMPregulated gene transcription. Proc Natl Acad Sci USA 91:8517–8521, 1994. 280. Pedram A, et al: Integration of the non-genomic and genomic actions of estrogen. Membrane-initiated signaling by steroid to transcription and cell biology. J Biol Chem 277:50768–50775, 2002. 281. Ascoli M, Fanelli F, Segaloff DL: The lutropin/choriogonadotropin receptor, a 2002 perspective. Endocr Rev 23:141–174, 2002. 282. Simoni M, Gromoll J, Nieschlag E: The follicle-stimulating hormone receptor: Biochemistry, molecular biology, physiology, and pathophysiology. Endocr Rev 18:739–773, 1997. 283. Bourne HR, Sanders DA, McCormick F: The GTPase superfamily: Conserved structure and molecular mechanism. Nature 349:117–127, 1991. 284. Hirsch B, et al: The C-terminal third of the human luteinizing hormone (LH) receptor is important for inositol phosphate release: Analysis using chimeric human LH/follicle-stimulating hormone receptors. Mol Endocrinol 10:1127–1137, 1996. 285. Monaco L, Adamo S, Conti M: Follicle-stimulating hormone modulation of phosphoinositide turnover in the immature rat Sertoli cell in culture. Endocrinology 123:2032–2039, 1988. 286. Hirakawa T, Galet C, Ascoli M: MA-10 cells transfected with the human lutropin/choriogonadotropin receptor (hLHR): A novel experimental paradigm to study the functional properties of the hLHR. Endocrinology 143:1026–1035, 2002.
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303. Piquette GN, et al: Regulation of luteinizing hormone receptor messenger ribonucleic acid levels by gonadotropins, growth factors, and gonadotropin-releasing hormone in cultured rat granulosa cells. Endocrinology 128:2449–2456, 1991. 304. LaPolt PS, et al: Regulation of inhibin subunit messenger ribonucleic acid levels by gonadotropins, growth factors, and gonadotropinreleasing hormone in cultured rat granulosa cells. Endocrinology 127:823–831, 1990. 305. Harwood JP, Clayton RN, Catt KJ: Ovarian gonadotropin-releasing hormone receptors. I. Properties and inhibition of luteal cell function. Endocrinology 107:407–413, 1980. 306. Kraus S, Naor Z, Seger R: Intracellular signaling pathways mediated by the gonadotropin-releasing hormone (GnRH) receptor. Arch Med Res 32:499–509, 2001. 307. Poulin B, et al: GnRH signalling pathways and GnRH-induced homologous desensitization in a gonadotrope cell line (αT3-1). Mol Cell Endocrinol 142:99–117, 1998. 308. Millar RP, et al: Gonadotropin-releasing hormone receptors. Endocr Rev 25:235–275, 2004. 309. Chi L, et al: Cloning and characterization of the human GnRH receptor. Mol Cell Endocrinol 91:R1–R6, 1993. 310. Sealfon SC, Weinstein H, Millar RP: Molecular mechanisms of ligand interaction with the gonadotropin-releasing hormone receptor. Endocr Rev 18:180–205, 1997. 311. Karges B, Karges W, de Roux N: Clinical and molecular genetics of the human GnRH receptor. Hum Reprod Update 9:523–530, 2003. 312. Ullrich A, et al: Insulin-like growth factor I receptor primary structure: Comparison with insulin receptor suggests structural determinants that define functional specificity. Embo J 5:2503–2512, 1986. 313. Abbott AM, et al: Insulin-like growth factor I receptor gene structure. J Biol Chem 267:10759–10763, 1992. 314. Richards JS, et al: Novel signaling pathways that control ovarian follicular development, ovulation, and luteinization. Recent Prog Horm Res 57:195–220, 2002. 315. LeRoith D, et al: Molecular and cellular aspects of the insulin-like growth factor I receptor. Endocr Rev 16:143–163, 1995. 316. Massague J: TGF-β signal transduction. Annu Rev Biochem 67: 753–791, 1998. 317. Lin SY, et al: Regulation of ovarian function by the TGF-β superfamily and follistatin. Reproduction 126:133–148, 2003. 318. Mathews LS, Vale WW: Expression cloning of an activin receptor, a predicted transmembrane serine kinase. Cell 65:973–982, 1991. 319. ten Dijke P, et al: Activin receptor-like kinases: A novel subclass of cell-surface receptors with predicted serine/threonine kinase activity. Oncogene 8: 2879–2887, 1993. 320. Lebrun JJ, Vale WW: Activin and inhibin have antagonistic effects on ligand-dependent heteromerization of the type I and type II activin receptors and human erythroid differentiation. Mol Cell Biol 17:1682–1691, 1997.
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Oogenesis Mylene W. M. Yao and Kshonija Batchu
INTRODUCTION
OVERVIEW OF OOGENESIS
Oogenesis is an area that has long been of interest in medicine, as well as biology, economics, sociology, and public policy. Almost four centuries ago, the English physician William Harvey (1578–1657) wrote ex ovo omnia—“all that is alive comes from the egg.” Oogenesis exemplifies many fundamental biologic processes, such as mitosis, meiosis, and intracellular and intercellular signaling. The process of oogenesis begins with migratory primordial germ cells (PGCs) and results in an ovulated egg containing genetic material, proteins, mRNA transcripts, and organelles that are essential to the early embryo. Although our understanding of these basic mechanisms has increased significantly over the past few decades, we are still limited in our ability to treat female infertility due to “poor oocyte quality” or to identify women at risk for this condition to allow more patient-specific family planning. Currently, poor oocyte quality refers to a broad spectrum of clinical conditions, including poor response to exogenous gonadotropins, recurrent pregnancy loss or congenital anomalies due to aneuploidy, and abnormalities of oocyte maturation, fertilization, and early embryo development that are observed during in vitro fertilization (IVF) treatment. Because these conditions are more prevalent in older women, they also carry serious social implications for women and their partners in family planning. Many aspects of oogenesis and meiosis are well conserved across sexually reproducing species. Experimental work on the nematode Caenorhabditis elegans, the fruit fly Drosophila melanogaster, the frog Xenopus laevis, and the fission and budding yeasts Saccharomyces cerevisiae and S. pombe, respectively, has provided us with much insight into these processes. However, there are key differences in oogenesis between mammalian and nonmammalian species. As with many processes in development, oogenesis is extremely similar between mice and humans. Thus, in vivo gene-targeted and in vitro oocyte maturation models in the mouse have been most informative and relevant to our understanding of mammalian oogenesis. The generation of healthy eggs with the correct genetic complement and the ability to develop into viable embryos requires that oocyte development and maturation be tightly regulated. In an effort to describe in detail our current understanding of the basic biologic mechanisms behind this process, this chapter discusses mammalian oogenesis as it is understood in the mouse model (Fig. 3-1) and highlights clinical conditions that are related to defects in oogenesis.
Oogenesis begins in the early embryo with PGCs, which migrate from the yolk sac to the urogenital ridge to establish the germline. Upon sexual differentiation, PGCs give rise to oogonia, which undergo mitosis to expand the population in the developing female gonad. Oogonia become oocytes as they enter meiosis I. During prophase of meiosis I, oocytes undergo DNA replication, homologous chromosome pairing, synopsis, and recombination, but then remain arrested at the diplotene stage of prophase I until sexual maturity. While the oocyte remains in meiotic arrest, it continues to increase in size coordinately with follicular growth. Before meiotic resumption, the fully grown oocyte is characterized by the presence of the germinal vesicle (GV), which is the meiotic counterpart of the nuclear envelope in somatic cells. Gonadotropin-dependent follicular growth is followed by oocyte maturation, which refers to the resumption and completion of meiosis I in the oocyte. This process occurs at each estrus cycle in mice and at each menstrual cycle after the onset of puberty in humans. On mating in an estrus cycle in the mouse, luteinizing hormone (LH) and cumulus–oocyte signaling result in decreased cyclic adenosine monophosphate (cAMP) in a cohort of oocytes. These oocytes resume meiosis and undergo GV breakdown (GVBD). Condensation of chromosomes is followed by congression of homologous chromosomes at metaphase I and segregation at anaphase I. Extrusion of the first polar body signifies exit from meiosis I and concomitant entry into meiosis II, whereupon the eggs are arrested at metaphase II until fertilization with sperm. After fertilization, they exit meiosis II and transition into one-cell embryos. In the human menstrual cycle, a cohort of follicles is similarly recruited to resume meiosis, but typically only one dominant follicle develops, so that only one oocyte completes meiosis I and is released during the endocrine- and paracrine-mediated process of ovulation.
PRIMORDIAL GERM CELLS Primordial germ cells are the founder cells of the gametes. In many species, including Drosophila, Danio rerio (zebrafish), and C. elegans, germ cells are derived from germ plasm, which is maternally derived cytoplasm that contains germ cell determinants. In contrast, mammalian PGC fate is thought to be induced by cell–cell interaction requiring the adhesion molecule E-cadherin and signaling from surrounding tissues.1,2 The migration of PGCs from the base of allantois to the genital ridges has been mapped out by alkaline phosphatase
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GV
N
A
GV
ZP
25μm
B
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C
D
E
F
G
H
Metaphase I
Metaphase I arrest
Figure 3-1 Stages of oocyte maturation. Oocytes and their corresponding chromosomes at various stages of maturation, as visualized by differential interference contrast (DIC) [A, C, E, G, I, K] and 4′6-diamidino-2-phenylindole (DAPI) stain [B, D, F, H, J, L], respectively. DAPI stain binds to natural double-stranded DNA in the chromosomes and allows chromosomes to be visualized in live cells. A, An oocyte at the germinal vesicle (GV) stage (center). GV, germinal vesicle; N, nucleolus; ZP, zona pellucida. B, The same oocyte under milliseconds of exposure to UV light, upon which DAPI-stained chromosomes are visualized as fluorescent structures. The chromosomes (arrow) are localized to the periphery of the nucleolus and assume the “surrounding nucleoli” configuration indicative of meiotic competence (see text for detailed explanation). C, D, An oocyte that has undergone germinal vesicle breakdown and is in pro-metaphase I, as indicated by complete disappearance of both GV and nucleoli on DIC and the presence of condensed bivalents (arrow). E, F, An oocyte in metaphase I. The chromosomes (arrow) are aligned at the metaphase plate and individual bivalents cannot be distinguished. G, H, An oocyte that has been cultured in media containing the proteasome inhibitor MG132 (2.5 μM) for 24 hours. Proteasome inhibition causes this oocyte to be arrested at metaphase I, and congression of chromosomes (arrow) remains at the metaphase plate.
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staining; more recently, their migration in vivo has been visualized by green fluorescent protein (GFP) expressed under the control of a truncated Oct-4 promoter (GFP:Oct-4) acting specifically in PGCs.3,4 Primordial germ cells are derived extragonadally from yolk sac endoderm and part of the allantois that arises from the posterior part of the primitive streak.
Primordial germ cells can be distinctly identified at 7.5 days post-coitum (dpc, a measure of embryonic age) during gastrulation by their high expression of alkaline phosphatase or GFP:Oct-4. At 7.5 dpc, PGCs are seen at the root of the allantois, from which they migrate along the endoderm via passive transfer mechanisms, to arrive at the epithelial layer of the hindgut at 8 dpc. Then, with
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Chapter 3 Oogenesis
Metaphaseanaphase transition
I
J
K
L
1st Polar body extruded (metaphase II)
Figure 3-1 Cont’d I, J, An oocyte (top) in the metaphase–anaphase transition, as indicated by chromosomes that are in the process of segregating. The bottom oocyte has extruded the first polar body, which is indicated by the condensed chromosomes (single spot). (The chromosomes in the oocyte proper are not seen on this plane.) K, L, An oocyte (center) that is in metaphase arrest, which is indicated by extrusion of the first polar body. Note a very faint fluorescent spot, which represents very condensed chromosomes that are tightly localized in the first polar body. Chromosomes in this metaphase II-arrested oocyte are aligned at the metaphase plate. These chromosomes appear fainter and not in optimal focus because their focal planes are slightly different. (Due to the thickness of the oocyte [≈80–100 μm], optimal visualization of both sets of chromosomes may not be possible if they are in different focal planes.)
the acquisition of motility via long pseudopodia, they traverse through the wall of the hindgut at 9 dpc.3 At 9.5 to 11.5 dpc, they migrate along the dorsal mesentery toward the genital ridges in the roof of the coelomic cavity. PGCs remain sexually undifferentiated until 12.5 dpc, when they coalesce with the mesodermally derived somatic components of the gonads to form ovaries or testes. During the process of migration, PGCs undergo proliferation by mitosis at approximately every 18 hours, so that their population increases from fewer than 100 founder cells to approximately 3,000 cells by 11.5 dpc and approximately 25,000 cells by 13.5 dpc.
Specific Genes Expressed for Migration of Primordial Germ Cells Several genes are known to be required for PGC cell fate determination, migration, and survival in the mouse embryo. Bone morphogenetic protein 4 (Bmp4) and Bmp8b are maximally expressed in the extraembryonic ectoderm adjacent to the proximal epiblast, where precursors of PGCs are localized at 6.5 dpc.5,6 These two proteins are thought to have essential roles in the differentiation of PGC precursors into PGCs because PGCs are absent in both Bmp4 and Bmp8b homozygous null mutant mouse models.6,7 Bone morphogenetic proteins are members of the transforming growth factor β (TGFβ) superfamily of growth factors, which also includes the TGFβ family and activins. These signaling molecules have diverse and often critical functions during embryonic development and in adult tissue homeostasis. They signal via formation of heterodimers or homodimers of the highly conserved
carboxyl-terminal domain, which is characterized by six or seven cysteine residues that are critical to the structure, stability, and function of these proteins. TGFβ superfamily members signal by binding to serine/threonine kinase cell membrane receptors that leads to phosphorylation of proteins of the Smad family (named after the C. elegans gene sma and Drosophila gene Mad, reviewed in Shi and Massague8). Smad complexes can bind DNA and mediate transcriptional activation or repression. Smad1 and Smad5 are known to act downstream of the Bmp signaling pathway and may have important functions in PGC development because loss of these proteins results in decreased size of the PGC population.9–11 Migration of PGCs through the hindgut and along the mesentery is mediated by the binding of c-Kit, a tyrosine kinase receptor expressed in PGCs, to its ligand, stem cell factor (Scf). Scf is expressed by somatic cells and its gradient along the migratory path is thought to direct the migration of PGCs. Mutations in the dominant white spotting (W) and Steel loci, which encode c-Kit and Scf, respectively, result in defects in gametogenesis. Although PGCs form, they do not proliferate, migrate to ectopic sites, and aggregate prematurely, so that the genital ridges are poorly populated by germ cells and the animals are sterile.12,13 Interestingly, these mutant mouse models also exhibit defects in melanogenesis and hematopoiesis because these genes are also required for the migration of melanocytes and mast cells.14 PGCs also express integrin subunits, which may potentially interact with laminin and fibronectin produced by cells in the genital ridges during the formation of the gonads. For example, integrin β1 is required for PGC colonization of the gonads, as the migration of PGCs is arrested at the gut endoderm in integrin β1 null mutants.15
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Section 1 Basic Science OOGONIA AND THEIR MEIOTIC ENTRY TO BECOME OOCYTES Colonization of the genital ridges by PGCs occurs concomitantly with the formation of the ovaries, at 12 to 13 dpc. Postmigratory PGCs, together with somatic epithelial cells that have derived from the coelomic epithelium and mesenchyme, form the ovarian cortical sex cords. Germ cell survival beyond 13 dpc requires the C2H2-type zinc-finger transcription factor Zpf148, which may activate tumor suppressor protein p53 in germ cells at this stage of development.16 Around the same time, PGCs differentiate into oogonia, which are sexually differentiated germ cells that would undergo the last rounds of mitotic divisions to establish the germ cell population at 11 to 13 dpc.17 Our understanding of mammalian oogonium function has been limited, perhaps due to their transient existence. Incomplete cytokinesis during synchronous, mitotic divisions of the oogonia results in the formation of clusters, or cysts, that are connected by intercellular bridges 0.5 to 1.0 μm in diameter.17 Oogonia become oocytes by entering meiosis I at 14 dpc; by 17 dpc, most oogonia have transitioned to oocytes. In the perinatal period, these germ cell cysts undergo breakdown, after which only a third of the oocytes survive and become enclosed in a single layer of granulosa cells to form primordial follicles.17 Thus, perinatal germ cell apoptosis appears to be a developmental process that is differentially regulated compared to the loss of oocytes during follicular atresia that occurs in the sexually mature animal. Pepling and Stradling suggested that cyst formation and subsequent breakdown may serve to ensure the incorporation of mitochondria from dying oocytes into those that survive.17
Oocyte Development The female germ cell becomes an oocyte when it enters prophase of meiosis I. The signals that instruct the germ cell to enter meiosis are not known. Further, we do not know whether this decision is cell-autonomous or whether it is dependent on signaling from adjacent somatic cells. Nevertheless, we do know that all oogonia have entered prophase to become oocytes by 17 dpc. DNA replication, chromosome pairing, and recombination, which are hallmarks of sexual reproduction ensuring that all eggs contain a unique haploid complement of DNA, occur in prophase. Prophase of Meiosis I
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The four stages of prophase I are leptotene, zygotene, pachytene, and diplotene. DNA replication is finalized in preleptotene, and in leptotene, sister chromatids search for their homologous counterparts. Formation of recombination nodules also commences at this time to facilitate interaction between homologous chromosomes. In zygotene, homologous chromosomes pair and begin to synapse. Their synapses are maintained by the synaptonemal complex, which is formed by many protein subunits, including synaptonemal complex protein 3 (Scp3) in the axial elements, Scp1 in the central element, and Scp2.18 Synapsis is completed in pachytene and continues to be maintained until diplotene, when homologous chromosomes are held together mainly at sites of chiasmata. The crossing-over and recombination of chromosomes occur over 4 days in the pachytene stage, prior to the formation of ovarian follicles.
Many proteins, including those with functions in DNA mismatch repair, recombination, and DNA damage checkpoint, have essential roles during prophase I. Gene-targeted mouse models deficient in these proteins exhibit female meiosis phenotypes ranging from premature ovarian failure due to perinatal oocyte loss, to defects that become apparent only later during oocyte maturation. These proteins are also required in spermatogenesis, which demonstrates mechanisms of prophase I that are common to both sexes, although the meiosis phenotypes tend to be more severe and occur in slightly earlier stages of development in males. Our discussion focuses on the requirement of these proteins in oogenesis. MutL and MutS Families of Proteins
DNA mismatch recognition and repair by the MutL and MutS families of proteins are well conserved from yeast to humans.19 MutL and MutS heterodimeric protein complexes are thought to interact to activate DNA mismatch repair. Although the MutL and MutS vertebrate homologs (Mlh and Msh, respectively) are generally known for their roles in maintaining genomic stability against tumor formation, gene targeting in mice revealed that Mlh1, Mlh3, Msh4, and Msh5 have essential functions in meiosis in both males and females.20–24 Mlh1 and Mlh3 homozygous mutant females have similar infertility phenotypes, in which the newborn ovaries appear normal with a normal number of follicles at various stages of development. However, there is a significant decrease in the number of oocytes that can complete meiosis I, meiosis II, and undergo subsequent development to two-cell embryos.21,23 Both Mlh1 and Mlh3 colocalize to chromosomes in pachytene and are thought to have critical functions in meiotic recombination, as supported by the decreased number of chiasmata formed in the oocytes of these mutant animals.21,23,25 Although oocytes seem to enter and arrest at diplotene, chromosomes are unpaired and cannot stably attach to the bipolar spindle, which leads to abnormal meiotic I spindle formation, abnormal or incomplete meiosis I, and fertilization failure.25 Further, in both human and mouse pachytene oocytes, MLH1 and MLH3 serve as molecular markers of recombination nodules, which are necessary for the crossover structures that are present in the diplotene stage.26 Similarly, Msh4 and Msh5 have essential functions in pachytene of prophase I, although their phenotypes were more severe.20,22,24 Female null mutants of Msh4 and Msh5 have significant loss of oocytes by postnatal days 2 to 4, before meiotic arrest at the diplotene stage.20,22,24 Their oocytes enter leptotene to form synaptonemal complexes but fail to undergo complete pairing at zygotene and fail to enter diplotene. These oocytes undergo apoptosis, which results in atretic follicles, loss of follicular architecture, and premature ovarian failure. Both Msh4 and Msh5 localize to chromosomes, can form heterodimers in vitro, and are thought to function at the same time point during chromosomal synapsis.22 The relevance of these findings from the mouse model to human reproduction is further supported by the expression of MSH4 and MSH5 in the human testes and ovaries.27 We do not yet know the exact mechanisms by which these Mlh and Msh proteins act or how they bind to chromosomes. The oocyte apoptosis phenotype has been attributed to failure of chromosome pairing or formation of synapses. However, recent genetic analyses based on the Spo11/Msh or Spo11/Mlh double null mutants indicate that oocyte apoptosis is a consequence of failure
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Chapter 3 Oogenesis to repair double-strand breaks.28 Spo11 initiates double-strand breaks, which are required for recombination. In the absence of Spo11, the phenotype of Mlh1 and Msh5 was less severe and resembled that of Spo11. Similarly, Dmc1, another protein involved in recombination, and ataxia-telengiectasia mutated (Atm), a DNA damage checkpoint protein, are both required for the repair of double-strand breaks; in their absence, persistent doublestrand breaks lead to oocyte death via apoptosis.28 The functional mechanism of a protein is often elucidated by identifying proteins with which it associates and the nature of their interactions. The colocalization of Mlh1 proteins with Scp3 and cyclin-dependent kinase 2 (Cdk2) may suggest interaction or related functions, especially since Scp3 and Cdk2 have also been shown to be required in meiosis.29,30 Scp3 is a key protein subunit in the synaptonemal complex, which holds homologous chromosome pairs to facilitate synapsis. Female mice lacking Scp3 are subfertile, because many of their oocytes contain univalents (unpaired chromosomes), exhibit abnormal chromosomal segregation, and produce a decreased number of viable embryos. Interestingly, their fertility worsens with age, so that this model is thought to be potentially powerful in studying the age-related subfertility and aneuploidy that are major problems in human reproduction.30 Cdk Family of Proteins
Cyclin-dependent kinase (Cdk2) belongs to the family of Cdk proteins, which are considered master regulators of the cell cycle.31 However, Cdk2-null mutants are unexpectedly viable; thus, Cdk2 is not required for mitosis during development in vivo to be required for prophase I of meiosis in the oocytes instead. Oocyte loss and premature ovarian failure occur by the first few postnatal days. Although the precise molecular defects differ, a similar phenotype is seen in the null mutants of Dmc1, Msh4, Msh5, and Atm, presumably because these oocytes fail to enter or complete pachytene, and enter the common apoptotic pathway by default. In contrast, by postnatal day 5, all oocytes in wild type mice have progressed to the diplotene stage, where they remain arrested until peri-ovulation in the sexually mature adult, when they resume and complete meiosis.
OOCYTE DEVELOPMENT AND EARLY STAGES OF FOLLICULOGENESIS The transition from pachytene to diplotene marks the beginning of folliculogenesis, which is closely associated with subsequent oocyte development. Whereas no pachytene oocytes are found within follicles, approximately 80% of diplotene oocytes are enclosed in primordial or more developmentally advanced follicles.32 Primordial follicles are formed by the encapsulation of a diplotene-arrested oocyte by a single flat layer of granulosa cells. Subsequently, the granulosa cells, still in a single layer, assume a cuboidal shape to form primary follicles.
Transcription Factors Our understanding of primordial and primary follicular development has recently been enlightened by the discovery of the requirement of two transcription factors at these stages of development (Fig. 3-2). Figα, a β-loop-helix-loop transcription factor, is required for oocyte survival into the primordial follicle stage.33 Based on its known role in the transcription of oocyte-specific
genes zona pellucida 1 (zp1), zp2, and zp3, its role in primordial follicle formation is presumed to be the transcription of other oocyte-specific transcription factors.33 Another transcription factor, Nobox, which is an oocytespecific homeobox protein, has a critical role in the transition of primordial to primary follicles.34 In the absence of Nobox, mouse ovarian follicles do not develop beyond the primordial stage, which results in massive oocyte loss in the early postnatal period.34 Identification of novel downstream target genes of Figα and Nobox in the future should provide insight into these early stages of folliculogenesis.
Zona Pellucida The growing oocyte synthesizes zona pellucida glycoproteins, which comprise approximately 17% of the total cellular protein content. The zona pellucida proteins zp1, zp2, and zp3 are encoded by distinct genes and are coordinately expressed under the control of Figα during oocyte growth.33 These zona proteins form the zona pellucida or zona matrix that surrounds the growing oocyte, but each one has a critical role in proper oocyte and embryo development. zp1, the only zp protein that forms intermolecular disulfide bonds, contributes to 10% to 15% of the zona mass and is thought to provide structural integrity to the zona pellucida. zp3 serves as the receptor for sperm binding and the subsequent acrosome reaction; zp2 functions as a secondary receptor. Together, zp2 and zp3 mediate sperm binding and species specificity during fertilization. These three glycoproteins are essential for fertilization and viability of growing oocytes and early embryos. Mice lacking zp3 cannot form the zona matrix and are sterile,35 and zp1 knockout mice have decreased fecundity and precocious hatching of early embryos from the structurally compromised zona matrix.36 Further, ectopic granulosa cells are seen between the oolemma and zona pellucida, and may increase the perivitelline space prior to ovulation.36 It is important to note that these may be four zona pellucida genes that are expressed in humans (ZP1, ZP2, ZP3, and zPB). Interestingly, abnormalities and lack of zona pellucida in human oocytes have been observed during IVF; however, the cause and implication of this defect in human reproduction is not well understood.
Regulation of Folliculogenesis by Oocyte Morphogens Although bidirectional communication between the oocyte and follicular cells is required for the development of the meiotically competent oocyte, there is increasing support to view the oocyte as autonomous in determining its own fate by regulating follicular development via the secretion of various growth factors.37,38 The establishment of a morphogen gradient by the oocyte regulates follicular development via differential gene expression and function in granulosa cells. In the absence of these morphogens, folliclestimulating hormone (FSH) induces all cumulus cells, which are directly adjacent to the oocyte and have distinct functions, to differentiate into membrane granulosa cells. Currently, several members of the TGFβ superfamily are the most well-understood candidate oocyte morphogens. Transforming Growth Factor b
The mammalian oocyte expresses at least three TGFβ superfamily members: growth differentiation factor 9 (Gdf9), Bmp15, and
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Section 1 Basic Science Time course
Developmental stages
Essential regulators
6.5-7.5 dpc
PGCs: • Formation
Bmp4, Bmp8b, Smad1, Smad5
7.5-13.5 dpc
• Migration and proliferation
c-kit, Scf
• Colonization of the forming gonad
Intergin β1
Beyond 13 dpc • Post-migratory survival 12-13 dpc
Zpf148
Oogonia: • Proliferation by mitosis
14-17 dpc
Oocytes meiotic prophase1: • Preleptotene-replication of DNA • Leptotene: Search for homologous chromosomes
Type 1
Type 2
Type 3a/3b
• Zygotene: Pairing of homologous chromosomes and synapsis
Scp1, Scp2, Scp3
• Pachytene: Crossing over, recombination and DNA mismatch-repair
MIh1, MIh3, Msh4, Msh5 Spo11, Dmc1, Atm
18 dpc
• Diplotene: Meiotic arrest
dpp 1
Oocytes in dictyate stage (late diplotene)
dpp5 and beyond
Primordial follicle:
Fig α
• Diplotene arrested oocyte • Flat granulosa cell layer Primary follicle:
Nobox
• Diplotene arrested oocyte • Cuboidal granulosa cell layer Type 4
Type 5a
Type 5b
Pre-antral secondary follicle:
Connexins 37,43
• Late folliculogenesis • Granulosa proliferation
Gdf9, Bmp15
• Theca precursor formation Type 6
Type 7
Antral/Graffian follicle: • Formation of antrum
FSH/FSH receptor
• Timing and rate of follicular recruitment • Formation of pre-ovulatory follicles and corpora lutea LH/LH receptor Type 8
• Granulosa cell proliferation
ERα, ERβ receptors, Cyclin D2
Cumulus expansion: • Secretion of EGF family proteins — amphiregulin, epiregulin, betacellulin
LH signaling
Ovulation
PGE2, Cox2, ERα ERβ
Oocyte maturation and fertilization Figure 3-2 Schematic representation of oogenesis and folliculogenesis during development in the mouse model. This figure shows and correlates the developmental stages of the oocyte and follicle, and highlights examples of essential regulators at each stage. The “Types 1-8” nomenclature, as described by Pedersen and Peters191, is also shown to facilitate interpretation of the literature. PGCs, primordial germ cells; dpc, number of days postcoitum; dpp, number of days postpartum.
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Chapter 3 Oogenesis Bmp6.38 Although Gdf9 is expressed throughout the reproductive tract and bone marrow,39 its oocyte expression is restricted to oocytes in follicles at the primary (type 3a), preantral, or more advanced stages of development.39,40 After fertilization, the level of Gdf9 transcripts decreases to low or undetectable in preimplantation embryos.41 Gdf9 is a critical regulator of follicular development. In Gdf9deficient female mice, primordial and primary follicles appear normal, but development beyond type 3a follicles is blocked and the animals are sterile.42 Further, in the absence of Gdf9, theca cell precursors are absent around the follicles, and the expression of kit ligand and inhibin-α is upregulated in the granulosa cells of the primary follicles.43 The increased levels of kit ligand are thought to mediate excessive oocyte growth via interaction with the c-kit tyrosine kinase receptor on the oocyte, leading to abnormally large oocytes and their cell death.43 Interestingly, Gdf9 deficiency also causes failure of granulosa cells to proliferate or undergo cell death, which presumably leads to their abnormal differentiation into clusters of steroidogenic cells reminiscent of corpora lutea.43 Therefore, the oocyte can be viewed as the master regulator of early folliculogenesis via its secretion of Gdf9. The oocyte expression pattern of Gdf9 is shared by its family member Bmp15, which is encoded by an X-linked gene.44,45 Bmp15 homozygous null mutant females are subfertile due to decreased rates of ovulation and early embryo survival. Further, an effect of gene dosage is observed in Gdf9+/– Bmp15–/– mice, which have a more severe phenotype than Bmp15–/– mice.46 In addition, cumulus–oocyte reconstitution and RNA interference (RNAi) experiments demonstrated that both proteins regulate
cumulus expansion in vitro. Therefore, Gdf9 and Bmp15 are thought to have synergistic roles in the regulation of folliculogenesis. Interestingly, naturally occurring mutations in GDF9 and BMP15 are common in certain strains of domestic sheep, perhaps as a result of breeding practices. Although sheep carrying mutations in both alleles of GDF9 or BMP15 are sterile, those carrying a single mutant allele have increased ovulation rates and are “super fertile.” Superovulation in the presence of heterozygosity of either of these genes is thought to be caused by decreased inhibin production by granulosa cells, which in turn leads to increased pituitary FSH secretion, development of more than one dominant follicle, and ultimately superovulation. Thus, the paradoxical increase in fertility when one allele is mutated exemplifies the impact of gene dosage on ovarian follicular function.45
RECRUITMENT OF OVARIAN FOLLICLES Nongrowing mouse oocytes within primordial follicles have a diameter of approximately 12 μm and comprise the resting pool. Cohorts from the resting pool are continuously induced by ovarian paracrine signals to undergo coordinated oocyte and follicular growth during a process called initial recruitment (Fig. 3-347). The recruited, growing follicles are called primary follicles, but this growth phase is very protracted so that primordial and primary follicles may not be easily distinguishable. These growing follicles subsequently develop into secondary and antral follicles. (The timeline of different stages of follicular development in humans and rodents are shown in Fig. 3-4 and 3-5.47)
Figure 3-3 Life history of ovarian follicles: endowment, maintenance, initial recruitment, maturation, atresia or cyclic recruitment, ovulation, and exhaustion. A fixed number of primordial follicles are endowed during early life, and most of them are maintained in a resting state. Growth of some of these dormant follicles is initiated before and throughout reproductive life (initial recruitment). Follicles develop through primordial, primary, and secondary stages before acquiring an antral cavity. At the antral stage most follicles undergo atresia; however, under the optimal gonadotropin stimulation that occurs after puberty, a few of them are rescued (cyclic recruitment) to reach the preovulatory stage. Eventually, depletion of the pool of resting follicles leads to ovarian follicle exhaustion and senescence. (From McGee EA, Hsueh AJW: Initial and cyclic recruitment of ovarian follicles. Endocrine Reviews 21:200–214, 2000; with permission. Copyright 2000, The Endocrine Society.47)
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Section 1 Basic Science
Figure 3-4 Duration of follicle recruitment and selection in human and rat ovaries. Primordial follicles undergo initial recruitment to enter the growing pool of primary follicles. Due to its protracted nature, the duration required for this step is unknown. In the human ovary, more than 120 days are required for the primary follicles to reach the secondary follicle stage, whereas 71 days are needed to grow from the secondary to the early antral stage. During cyclic recruitment, increases in circulating follicle-stimulating hormone (FSH) allow a cohort of antral follicles (2 to 5 mm in diameter) to escape apoptotic demise. Among this cohort, a leading follicle emerges as dominant by secreting high levels of estrogens and inhibins to suppress pituitary FSH release. The result is a negative selection of the remaining cohort, leading to its ultimate demise. Concomitantly, increases in local growth factors and vasculature allow a positive selection of the dominant follicle, thus ensuring its final growth and eventual ovulation. After cyclic recruitment, it takes only 2 weeks for an antral follicle to become a dominant graafian follicle. In the rat, the duration of follicle development is much shorter than that needed for human follicles. The time required between the initial recruitment of a primordial follicle and its growth to the secondary stage is more than 30 days, whereas the time for a secondary follicle to reach the early antral stage is about 28 days. Once reaching the early antral stage (0.2–0.4 μm in diameter), the follicles are subjected to cyclic recruitment, and only 2 to 3 days are needed for them to grow into preovulatory follicles. (From McGee EA, Hsueh AJW: Initial and cyclic recruitment of ovarian follicles. Endocrine Reviews 21:200–214, 2000; with permission. Copyright 2000, The Endocrine Society.47)
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The oocyte grows from approximately 12 μm to approximately 80 μm in the fully grown state, which is achieved prior to formation of the antral follicle in sexually mature mice. In general, antral follicles tend to undergo follicular atresia, which is initiated by apoptosis in the granulosa cells, unless they are rescued by increased levels of FSH in the estrus or menstrual cycles in mice and humans, respectively. This cyclic recruitment of antral follicles results in the rescue and continued development of a few follicles, but usually only one dominant follicle prevails and develops to the periovulatory stage in the human menstrual cycle.47 Although cyclic recruitment is operative after puberty in humans, most antral follicles ultimately undergo atresia, which results in oocyte death. Primordial follicles that have not been recruited are thought to remain dormant and be available for recruitment at a later time. Therefore, maintenance of the pool of nongrowing oocytes is necessary to sustain a normal reproductive life span. Müllerian inhibiting substance or antimüllerian hormone, a TGFβ superfamily member well-known for its regulatory role in the sexual differentiation of the reproductive tract during development, is expressed in granulosa cells of growing follicles starting in the perinatal period.48 During folliculogenesis, it inhibits the recruitment of primordial follicles to the pool of growing follicles by decreasing the responsiveness of granulosa cells to FSH.49 Antimüllerian hormone is recognized as an important clinical marker of the ovarian reserve of viable follicles.
Regulation of Folliculogenesis by Gonadotropins Preantral follicle development, which involves oocyte growth with limited granulosa cell proliferation, is regulated predominantly by paracrine and autocrine signals. Although gonadotropins are not required for early follicle development in vivo, these follicles can develop in response to FSH in vitro.47 In contrast, gonadotropins are required for antrum formation and the rapid granulosa cell proliferation that results in the graafian or antral follicle. Follicular growth from the primary and secondary follicles to antral stages takes several weeks in the mouse and several months in many larger mammals, including humans. The Graafian follicle can exceed 600 μm and contains more than 50,000 granulosa cells. Granulosa cells fall into two distinct subtypes—cumulus and mural granulosa cells—that exhibit differential morphologic features and functions. Mural granulosa cells, located in the periantral and outer membrane regions, express FSH receptor (FSHR) and are responsive to FSH. FSHR comprises a large extracellular domain that binds the FSH hormone with high affinity, and a seven membrane-spanning domain that activates downstream cyclic adenylate cyclase signaling via the heterotrimeric G proteins.50 Mice deficient in the FSH β subunit, which normally forms heterodimers with the α subunits, are infertile due to arrested follicular development prior to formation of the antrum.51
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Chapter 3 Oogenesis theca cells and their expression of the LH receptor and P450 aromatase genes are independent of FSH signaling, expression of these genes in granulosa cells is dependent on FSH signaling.54 Similarly, the genes encoding for inhibin and activin subunits, whose homodimers and heterodimers are thought to be important paracrine and autocrine mediators of follicular growth, have decreased expression levels in granulosa cells in the FSHβ knockout model.54 Other genes that are dysregulated as a result of FSHβ deficiency include those encoding for androgen receptor (AR), estrogen receptor β (ERβ), and cyclin D2, all of which have been shown to be essential in the final stages of follicular development.54
Estrogen Receptors Figure 3-5 Landmarks of follicular development during fetal and neonatal life in humans and rodents. In the human ovary, primordial follicles are present by 20 weeks of fetal life, whereas primary follicles are found by 24 weeks. By 26 weeks, some follicles have progressed to the secondary stage. Antral follicles develop in the third trimester and are also seen postnatally when follicle-stimulating hormone (FSH) levels are elevated. After puberty, cyclic increases in serum gonadotropins stimulate the antral follicles to become preovulatory follicles during each menstrual cycle. In the rat ovary, primordial follicles are formed by 3 days after birth when the first wave of follicles begins growth. These follicles progress to the early antral stage during the third week of life when serum gonadotropin levels are elevated. After early antral follicles are formed, ovarian cell apoptosis increases. FSH receptors are found by day 7 of age, when secondary follicles are present, followed closely by the formation of luteinizing hormone (LH) receptors in the thecal cells. Cyclic ovarian function begins around day 35 of age. The neonatal rodent model allows analysis of early follicle development in a synchronized population of growing follicles. Pmd, primordial. (From McGee EA, Hsueh AJW: Initial and cyclic recruitment of ovarian follicles. Endocrine Reviews 21:200–214, 2000; with permission. Copyright 2000, The Endocrine Society.47)
Consistent with the critical role of FSH signaling via its receptor, follitropin receptor knockout (FORKO) mice are also infertile.52 At postnatal day 2, there are fewer nongrowing but more growing follicles, but by postnatal day 24, the numbers of resting and growing follicles are both decreased. Therefore, postnatal recruitment of resting follicles into the growing phase appears to be aberrantly accelerated, followed by arrest in further follicular recruitment later on. Further, no antral follicles are observed. Although these mouse models confirm that FSH signaling is required for follicular development beyond the preantral stage, the phenotype of the FORKO mice also suggests that FSHR signaling is essential in the regulation of the timing and rate of follicular recruitment.52 In contrast, luteinizing hormone receptor knockout mice (LuRKO) females are infertile, presumably due to defects in the later stages of folliculogenesis because follicles up to the early antral stage are present, but preovulatory follicles and corpora lutea fail to form.53 FSH and FSHR-mediated downstream intracellular signaling results in gene and protein expression that exemplifies granulosa cell function. For example, antimüllerian hormone, which is implicated in primordial follicle recruitment, exhibits an aberrant expression pattern in FORKO mice.52 Although recruitment of
Two estrogen receptors, ERα and ERβ, are expressed in granulosa cells in the antral follicle. Different knockout models have been generated for these two receptors based on different strategies of gene targeting, but they produced similar phenotypes.55 ERαKO females are infertile; ERβKO females are subfertile. In both ERαKO and ERβKO mice, folliculogenesis progresses normally until the large antral stage, when ERβ is critical for ER-mediated granulosa cell proliferation and subsequent ovulation. In contrast, ERα is not critical for follicular growth but is required for ovulation. The ERαβKO females clarify the question of functional redundancy between the two ERs by demonstrating that in the absence of ERs, antral follicles only have single layers of granulosa and theca cells, multiple small pockets of antral fluid, and oocytes that are dissociated from cumulus cells.55
D-type Cyclin Granulosa cell proliferation in late folliculogenesis also requires cyclin D2, which belongs to the D-type cyclin family of cell cycle regulators that promote the transition from G1 to S phases via binding to Cdk4 or Cdk6.56 Cyclin D2–deficient females have decreased FSH-mediated granulosa cell proliferation, which results in antral follicles that have significantly fewer layers of granulosa cells. This defect in granulosa cell proliferation also results in ovulation failure on stimulation by LH. However, the number of follicles is not decreased, luteinization of theca cells proceeds, and follicles differentiate to become corpora lutea. We learn from the cyclin D2–deficient mutants that although these final stages of folliculogenesis and ovulation require cyclin D2 via FSHR-mediated activation, specifically of protein kinase A (PKA), oogenesis per se does not require these last rounds of granulosa cell proliferation. In fact, the oocyte not only appears normal, but it is also competent to undergo meiotic resumption and fertilization to produce viable embryos.56 Therefore, although oogenesis and folliculogenesis are closely intertwined, oocyte development is a cell-autonomous process to a certain extent, especially in the advanced stages and at periovulation.
THE ROLE OF CUMULUS CELLS IN OOGENESIS Cumulus cells, also called corona radiata, are specialized granulosa cells that directly line the oocyte. In addition to their supportive role in cytoplasmic maturation of the oocyte, they have important
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Section 1 Basic Science functions in oocyte development, including the maintainenance of meiotic arrest and induction of ovulation. Ovulation is a broad term that encompasses the processes of follicular luteinization, follicle rupture, and meiotic resumption in the oocyte. A critical step during LH-induced ovulation is the cumulus cellmediated cumulus expansion. Mural granulosa cells express LH receptor, which allows them to respond to LH by secreting proteins of the epidermal growth factor (EGF) family—amphiregulin, epiregulin, and betacellulin—which are thought to act as paracrine signals that lead to cumulus expansion.57 During this process, cumulus cells disperse in the extracellular matrix, which comprises hyaluronic acid, tumor necrosis factor-stimulated gene 6 (TSG6), and serum-derived inter-α-inhibitor, all of which are essential for follicular rupture.58 The cumulus expression of Tsg6 and several other proteins implicated in cumulus expansion is regulated by prostaglandin E2 (PGE2) via its receptor EP2.58 Consistent with the critical role of PGE2 in cumulus expansion and ovulation, mice deficient in either EP2 or cycloxygenase-2 (Cox-2), which is the ratelimiting enzyme for PGE2, are infertile due to their inability to ovulate.58–60
hypotheses attempt to explain how and to what extent cumulus cells mediate the high oocyte intracellular cAMP levels that are required to maintain meiotic arrest even after the oocyte has acquired meiotic competence.64 Although the complete story remains to be told, several key players have been identified.
MAINTENANCE OF MEIOTIC ARREST The oocyte is maintained in meiotic arrest via developmental stage-specific mechanisms. Before reaching the fully grown stage, the oocyte is intrinsically incompetent, but once the fully grown oocyte acquires meiotic competence, cumulus cells are thought to contribute at least partially to the maintenance of meiotic arrest. It is well known that fully grown oocytes isolated from surrounding cumulus cells spontaneously undergo meiotic resumption independent of LH signaling. Although the signal that confers cumulus regulation of arrest has not been identified, the signaling cascade within the oocyte compartment has become much better understood.
GTP-binding Protein Connexin and Gap Junctions
60
Cumulus cells mediate many of their important functions by communicating through gap junctions among themselves as well as with the oolemma. These gap junctions are intercellular channels formed by proteins of the connexin family for the diffusion of sugars, amino acids, lipid precursors, nucleotides, metabolites, and signaling molecules. Connexin family members share the same protein domains, including four membrane-spanning domains, two extracellular loops, a cytoplasmic loop, and cytoplasmic N- and C-terminals.61 In mice, there are at least 17 connexin proteins, whose distinct sequence or length in the cytoplasmic loops and C-terminal tails, as well as heterodimeric and homodimeric coupling, allow functional diversity. In mice, connexin (Cx) 32, 37, 43, 45, and 57 are expressed in the cumulus–oocyte complex, where they are located between cumulus cells, on cumulus transzonal projections that anchor cumulus cells into the zona pellucida, or on the microvilli or plasma membrane of the oocyte.61 The critical role of gap junctions in oogenesis is exemplified by the sterility phenotype found in Cx37-deficient mice. Cx37 is made by both the oocyte and granulosa cells, but it may be the only connexin member in cumulus–oocyte gap junctions that is contributed by the oocyte.61 In the absence of Cx37, follicular development fails at the preantral-to-antral transition, so that most follicles are arrested at the primary follicle stage, and only a few small antral follicles are present. Further, ovulation does not occur despite the formation of numerous corpora lutea.62 Similarly, in vitro experiments show that Cx43, which is also expressed in granulosa cells, is required for folliculogenesis beyond the primary follicle stage.63 Most importantly, oocytes from these two mutant mouse models are meiotically incompetent, which may reflect the requirement of cumulus cell communication in the acquisition of meiotic competence. These connexin-deficient experimental models demonstrate the critical role of gap junctions in folliculogenesis, but they do not explain the role of cumulus cells in the regulation of meiotic arrest and resumption in the oocyte. Numerous models and
The stimulatory heterotrimeric GTP-binding protein (Gs)-linked receptor 3 (GPR3) is expressed in the oocyte plasma membrane and is thought to mediate cumulus control of meiotic arrest. However, GPR3 is capable of activity independent of LH or cumulus cells also. The role of GPR3 is exemplified by ovarian sections from prepubertal GPR3–/– females in which meiotic stages beyond prophase I are seen in oocytes in intact early antral follicles in the absence of LH signaling or cumulus expansion.65 Similarly, inactivation of Gs by microinjection of an antibody specifically targeting Gs into the oocyte within an intact follicle allows the oocyte to resume meiosis even if cumulus cells remain adherent to the oocyte.65 GPR3 maintains activity of Gs in stimulating adenylyl cyclase to produce high cAMP levels, which in turn maintain PKA activity.65 Specifically, the isoform adenylyl cyclase 3 expressed by the oocyte is critical in generating sufficient cAMP.66 Acting downstream of the GPR3→Gs→cAMP→PKA signaling cascade, PKA-dependent phosphorylation of substrate proteins presumably inhibits meiotic resumption through as-yet unknown mechanisms that include suppression of M-phase promoting factor (MPF) activity; this represents an area of intense investigation.64
MEIOTIC RESUMPTION Whereas LH triggers ovulation by the cumulus cell compartment and release of the oocyte from meiotic arrest, the resumption and completion of meiosis may be regulated intrinsically to a large extent by the fully grown oocyte. Resumption of meiosis requires both decreased levels of intracellular cAMP and activation of MPF.64 Decreased production and increased degradation of cAMP in the oocyte appear to contribute to meiotic resumption. Decreased cAMP production is mediated by the inhibitory G protein, which in turn is activated by an oocyte-expressed G protein-coupled receptor called leucine-rich repeat-containing G protein-coupled receptor 8 (LGR8).67 Interestingly, the role of LH in meiotic resumption is demonstrated by this LGR8mediated decrease in cAMP levels, because LGR8 is stimulated
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Chapter 3 Oogenesis by insulin-like 3, which is expressed and secreted by ovarian theca cells in response to LH.67
Phosphodiesterase (PDE) On the other hand, the degradation and inactivation of cAMP in the oocyte are mediated by the oocyte-expressed cyclic nucleotide phosphodiesterase family member, PDE3A. GV oocytes from PDE3A–/– mice fail to resume meiosis in vivo and remain in the GV stage even after ovulation. In addition, meiosis does not resume even when fully grown GV oocytes from these mice are isolated from cumulus cells and cultured in vitro.68 Thus, the GPR3 and PDE3A knockout mouse models demonstrate their critical and opposing roles in the regulation of meiotic arrest and resumption, respectively. More importantly, these models also prove that ovulation and meiotic resumption, though usually occurring synchronously, are independent processes that can be differentially regulated.
Meiotic Competence and Oocyte Maturation Meiotic progression requires activation of MPF, which is composed of cyclin B and its protein kinase Cdk1 (also called p34cdc2).69 The requirement of MPF for the G→M transition in mitosis and meiosis is highly conserved across species. Activation and inactivation of many cell-cycle regulators are mediated via phosphorylation, a form of post-translational protein modification of specific residues. The dual phosphatase, Cdc25b, is required for the dephosphorylation of residues 14 and 15 of p34cdc2, which results in activating p34cdc2. Oocytes from Cdc25b–/– mice are unable to resume meiosis and remain arrested in prophase unless rescued by microinjection of Cdc25b mRNA.70 Active p34cdc2 accumulates rapidly through an autoamplification loop. Therefore, the rate-limiting step of MPF activation is thought to be the synthesis and accumulation of cyclin B. During oocyte growth, the level of active MPF increases and eventually reaches the threshold above which the oocyte becomes meiotically competent, which refers to its ability to undergo meiotic resumption. In general, meiotic competence is related to oocyte size, presumably because cytoplasmic volume reflects the accumulation of synthesized proteins, including cyclin B, p34cdc2, and Cdc25b, which are essential for meiosis.71 Oocytes that are smaller than 70 to 80 μm have not reached their full growth potential and have low rates of meiotic competence, whereas those approximately 100 μm are considered fully grown and tend to be able to undergo meiosis. Another predictor of meiotic competence is the presence of a surround nucleolar (SN) chromosomal localization pattern that can be visualized in the live oocyte with culture media containing Hoescht stain.72,73
Germinal Vesicle Breakdown (GVBD) The first observable morphologic change of meiotic resumption is GVBD, which is characterized by the sequential disappearance of GV and nucleolus that is frequently concurrent with a shift from central to ectopic localization of the GV. After GVBD, bivalents start to become organized at prometaphase and then align at the metaphase plate in metaphase I. At the anaphase–metaphase transition, chromosomes begin to segregate, and a cytoplasmic protrusion signifying late anaphase
may be visible. MPF activity increases as the oocyte progresses from GV, GVBD, to metaphase I, but then declines transiently between metaphase I and metaphase II.74,75 However, progress beyond metaphase I may not occur in some oocytes if molecular prerequisites are not met.76
Metaphase–Anaphase Transition The metaphase–anaphase transition is regulated by decreased MPF activity, suppression of protein kinase C (PKC) activity, and the activity of many other proteins.77–79 Decreased MPF activity is achieved by proteasome degradation of cyclin B, which is required for polar body extrusion (metaphase I–metaphase II) and at metaphase II exit on fertilization.80–83 Like many mitotic and meiotic cell cycle regulators, the proteolysis of cyclin B is mediated by ubiquitin and the anaphase-promoting complex (APC), which are well conserved and required for proteolysis of many proteins across species. The anaphase-promoting complex is an E3 ubiquitin ligase that transfers ubiquitin “tags” from E2 ubiquitin conjugating enzymes to substrates, such as cyclin B, thereby “tagging” them for recognition and proteolysis by the 26S proteasome.82 The essential role of the proteasome in meiosis is further supported by the metaphase I arrest phenotype that is seen in mouse and rat oocytes cultured in media containing chemical inhibitors of the proteasome.84,85
Meiotic Spindle Achievement of metaphase I depends on the formation of an intact meiotic spindle, which requires the cell cycle regulator, cell division cycle-6 homologue (Cdc6). Insight into this process is provided by oocytes in which Cdc6 expression is abrogated by the RNA interference technique.86 These oocytes undergo GVBD, but the meiotic spindle is not formed, and they fail to reach metaphase I. In the absence of the meiotic spindle, condensed chromosomes fail to form bivalents and do not align to form the metaphase plate. Instead, the chromosomes form a halolike structure and meiosis I is arrested with no cell division or extrusion of polar body.86 In the presence of a normal meiotic spindle, the oocyte will reach metaphase I and then undergo the metaphase–anaphase transition, which is an important event because defective chromosome segregation at this stage can lead to aneuploidy in the resulting egg and embryo. In mitosis, the centromeres of sister chromatids are held together by cohesin until the onset of anaphase, when cohesin cleavage by separase allows separation of sister chromatids.87–89 Inhibition of separase activity by securin prior to anaphase onset, and its subsequent activation at anaphase upon securin degradation via the APC, are critical in ensuring correct chromosomal segregation.90,91 The APC→securin→separase cascade is also required to ensure correct spindle function and homologous chromosome disjunction during the metaphase–anaphase transition in meiosis in the oocyte.92,93 Spindle Assembly Checkpoint (SAC)
Another mechanism that the oocyte has in common with mitotic cells to ensure the correct segregation of chromosomes is the spindle assembly checkpoint (SAC). SAC proteins detect whether chromosomes are properly aligned and whether kinetochores are
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Section 1 Basic Science attached to the spindle. SAC proteins control the onset of anaphase I through interactions with one another, the kinetochores of unaligned chromosomes, and Cdc20, which is a protein that mediates APC/C proteolysis. (Kinetochores are the sites of attachment of centromeres of the chromosomes to the microtubules of the spindle. Homologous chromosomes migrate to opposite poles through tension exerted by the spindle on the kinetochores.) If chromosome alignment is not complete, the SAC protein would inhibit APC/C to prevent precocious sister chromatid separation, which can cause aneuploidy in the resulting egg and embryo. Mitotic SAC proteins that also have essential spindle checkpoint functions during maturation of the mouse oocyte include Mad2, BubR1, and Bub1. Interference of the function of these proteins results in accelerated completion of meiosis I, presumably because anaphase occurs prematurely.94 Further, the abrogation of Mad2 expression has specifically been shown to increase the rate of aneuploidy, whereas its overexpression inhibits disjunction of homologous chromosomes.95 Therefore, the expression and function of these cell-cycle regulators are candidates to be investigated for their potential involvement in age-related aneuploidy in human oocytes. At the end of anaphase I, the first polar body is extruded, which is followed by reaccumulation of cyclin B levels. MPF reactivation is required for the synthesis of c-mos, which leads to activation of MAP kinase kinase and MAP kinase.96–100 This c-mos-mediated MAP kinase activity is critical for the maintenance of metaphase II arrest, as shown by the c-mos–/– mouse model. Unfertilized eggs from c-mos–/– mice fail to arrest at metaphase II, and undergo parthenogenetic activation, during which the second polar body is extruded in the absence of fertilization.101,102
NUCLEAR AND CYTOPLASMIC CHANGES DURING OOCYTE GROWTH The growing oocyte undergoes nuclear and cytoplasmic changes that pertain to nuclear organization, epigenetic regulation, transcription, translation, ultrastructural morphology, and organelle function. These changes are sometimes referred to as nuclear or cytoplasmic maturation, broadly defined based on their association with oocyte maturation, subsequent fertilization, or embryo development. Many of the morphologic changes of the oocyte have been elegantly described at the cellular and ultrastructural levels.103 Further, expression, translational modification, and function of cell-cycle regulators, also considered indices of cytoplasmic maturation, are discussed in this chapter under “Meiotic Competence and Oocyte Maturation.” In this section, we highlight some biochemical features characteristic of the oocyte around the time of maturation.
Transcriptional Regulation
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The growing oocyte is characterized by a high level of transcriptional activity that increases its total RNA content from approximately 0.2 ng in a small oocyte to approximately 0.6 ng in a fully grown oocyte.104 In growing oocytes, gonadotropin stimulation of follicles increases the proportion of transcriptionally inactive oocytes; thus granulosa cells are thought to have an important role in the regulation of transcriptional activity in the growing oocyte.105 The fully grown oocyte undergoes global transcriptional
silencing, which is a prerequisite for meiotic resumption, oocyte maturation, and subsequent embryo development.106 Therefore, messenger RNAs (mRNAs) that are synthesized during oocyte growth are not only utilized for the translation of proteins during the growth phase, but are also stored for protein synthesis in the fully grown stage, during oocyte maturation, or later in the early embryo. Thus, precise control of translation is vital to the function and ultimate developmental potential of the oocyte and embryo.
Regulation of Translation Translation requires modification of the mRNA transcript such as polyadenylation at the 3′ end (addition of a poly-A tail) and cap binding at the 5′ end. Such modifications are controlled by cis and trans elements. For example, the translation and accumulation of cyclin B1 is regulated via polyadenylation and cisregulatory mechanisms in the 3′ untranslated region (3′UTR) of the cyclin B mRNA transcript.107 Cis elements in the 3′UTR consist of a highly conserved U-rich sequence (CPE) in conjunction with a downstream hexanucleotide cytoplasmic polydenylation element, AAUAAA. Cis elements mediate polyadenylation via binding to the phosphorylated form of the CPE binding protein (CPEB), which is a trans-acting factor specific to the oocyte. The critical function of CPEB in the oocyte was demonstrated in CPEB knockout mice.108 In the absence of CPEB oogenesis arrested at the pachytene stage on 16.5 dpc, presumably because translation of SCPs 1 and 3 did not occur, which led to death and resorption of the oocytes.108,109 However, the requirement of CPEB at this early stage also precluded the function of this protein during oocyte maturation to be ascertained. Other regulatory mechanisms of translation involve inhibition of translation if the presence of certain proteins would interfere with oocyte maturation. For example, some mRNAs can be stored in the form of ribonuclear particles (RNPs), which do not support translation and prevent the misexpression of certain proteins.110 The importance of this mechanism is shown by the relative abundance of the Y-box protein family member, MSY2, which has an essential role in mediating translational silencing by RNPs and comprises 2% of the total protein content in the fully grown oocyte.111,112 In addition, poly-A-specific ribonuclease (PARN) mediates widespread deadenylation and subsequent degradation of mRNAs encoding for a variety of proteins, including zona pellucida proteins, actin, alpha tubulin, and Cx43, at the time of meiotic resumption.110 In contrast, the polyadenylation of certain cell-cycle proteins required during oocyte maturation (i.e., cyclin B1) is enhanced at meiotic resumption.113
Epigenetic Regulation In addition to regulation at the levels of transcription and translation, epigenetic regulatory mechanisms in the oocyte, sperm, and early embryo affect the expression of specific genes through the process of genomic imprinting, as well as the entire molecular program through global changes in methylation status and structural chromatin remodeling. Structural remodeling of chromatin is associated with significant changes in the nuclear architecture during oocyte growth and maturation. Chromosomes in the live mouse oocyte can be viewed using culture media containing Hoescht stain, a chemical that chelates
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Chapter 3 Oogenesis with the minor groove of DNA and emits blue fluorescent light upon UV light absorption. Centromeres and pericentromeric heterochromatin are initially located at the periphery of the nucleus in oocytes in primordial and primary follicles.106 Then during oocyte growth, they are spread within the nucleus, followed by localization to the periphery of the nucleolus. This perinucleolar heterochromatin rim, or karyosphere, appears as a bright rim around the nucleolus and is also known as the surround nucleoli (SN) pattern.73,114 Although the SN pattern is associated with global transcriptional repression and high potential for meiotic competence and embryo development, we now know that chromatin remodeling and transcriptional repression are distinct processes controlled by different mechanisms.106 As in somatic cells, histone deacetylases were also found to be critical for the large-scale chromatin remodeling in the fully grown oocyte because their inhibition resulted in a breakdown of the SN architecture and aberrant configuration of the meiotic chromosomes and spindle.106 Another important epigenetic mechanism that has emerged is control of transcriptional activation and repression via demethylation and methylation, respectively. Whereas the genome of somatic cell precursors undergoes remethylation before gastrulation at 6.5 dpc, the genome of PGC precursors remains demethylated at 12.5 dpc. Then partial methylation occurs at 15.5 dpc and methylation is completed by 18.5 dpc.32 The embryonic genome is inactivated until the two-cell stage in mice (eight-cell stage in humans), when it becomes activated by global demethylation. These global changes in methylation status are distinct from X-inactivation and genomic imprinting. Briefly, X-inactivation is a complex and random process in which one of the X chromosomes in XX mammalian females is inactivated to ensure an equivalent dosage of X-linked genes in XX females and XY males.115 Initiation of this process is controlled by a locus called Xinactivation center (Xic) at Xq13. This locus contains X-inactive specific transcript (Xist), which encodes a non-coding mRNA that coats the X-chromosome in cis to trigger inactivation115 (see Chapter 5). Genomic Imprinting
Finally, a more gene-specific mechanism of epigenetic regulation is genomic imprinting, which mediates predesignated, differential silencing of the maternal and paternal alleles.116 During gametogenesis, certain genes on autosomes become hypermethylated, or silenced, based on their parental origin. Once established, these imprints are thought to be protected from genome-wide demethylation. Imprinting possibly occurs at different time points in oogenesis, spermatogenesis, and embryogenesis for different genes. Congenital syndromes or cancer can result from a failure of the allele from the designated parental origin to be silenced or an effective null mutation based on a heterozygous mutation in the nonimprinted allele. These disease mechanisms and syndromes are further discussed in Chapter 5. The mechanism of imprinting is an area of research that is particularly relevant to reproductive endocrinology and infertility treatment because of reports associating assisted reproductive technologies (ART) with possible increased risk of imprinting defects.117 In addition, it has been suggested that in the mouse model, oocyte maturation and embryo culture in vitro may interfere with imprinting.118,119 However, because defects in
imprinting are rare in the general population and in children conceived through ART, it is difficult to determine the statistical significance in these studies. Consequently, whether there is a true association or a causal link remains an open question. If ART is indeed associated with imprinting defects, one would have to examine all possible causes, including controlled ovarian hyperstimulation (COH), clinical embryology, and the cause of infertility itself, because imprinting defects may be the cause of infertility that becomes unmasked by infertility treament. Therefore, this area warrants intense investigation to determine whether and how mechanisms of imprinting impact on future directions in ART.
THE OOCYTE–EMBRYO TRANSITION In addition to the maternal genome, the oocyte contributes specific gene products that are required for early embryo development prior to zygote gene activation. In the mouse model, zygote genome activation occurs at the two-cell stage, while in the human it occurs at the four- to eight-cell stage.
Maternal Effect Genes Because the oocyte does not synthesize new mRNA transcripts after meiotic resumption and the embryonic genome is not activated until the two-cell stage, the oocyte must store transcripts and proteins for all of its requirements during the oocyte–embryo transition. Genes encoding oocyte proteins that persist and have critical functions in the early stages of embryogenesis are called maternal effect genes. It is not surprising, therefore, that several proteins encoded by maternal effect genes—oocyte-specific linker histone H1 (H1F00), nucleoplasmin 2 (Npm2), DNA methyltransferase1 oocyte isoform (Dnmt1o)—are involved in mechanisms of epigenetic gene regulation; these processes are initiated in the oocyte, but continue during early embryo development.120–124 All of these maternal effect genes, and potentially ones that have yet to be discovered, serve as critical links to demonstrate how the unfertilized oocyte can affect subsequent embryo development, besides contributing to the embryonic genome. H1FOO is an oocyte-specific H1 linker histone that associates with chromatin during the GV and maturation stages; this association continues until the late two-cell to four-cell embryo stages when they are gradually replaced by somatic H1. Because somatic H1 linker histones are important in the regulation of chromatin function, the oocyte- and early embryo-specific expression of H1FOO suggests that it may be critical in chromatin remodeling during the oocyte–embryo transition.120,121 In contrast, Npm2, a protein that is present in the nuclei of oocytes and peri-implantation embryos, is proven to have an essential role in chromatin structure. Embryos of Npm2–/–mutant females lack Npm2, and die before implantation because Npm2 is required for the maintenance of normal nucleolar structures. Specifically, heterochromatin and deacetylated histone H3, which are usually localized to the rim of the nucleolus in oocytes and early embryos, are absent.122 Therefore, this mouse model also demonstrates the importance of chromatin regulation and nuclear architecture in early embryo development. Another maternal effect gene that is important in epigenetic regulation is Dnmt1. The oocyte variant, Dnmt1o, is an isoform
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Section 1 Basic Science of the Dnmt1 protein that is expressed only in the growing oocyte and early embryo, under an oocyte-specific promoter. Embryos derived from Dnmt1o-deficient oocytes are also deficient in Dnmt1o and develop into fetuses that die during gestation.123 These embryos have defective imprinting, as shown by inappropriate methylation at certain gene loci and loss of allelespecific gene expression. The critical function of Dnmt1o is thought to occur at the eight-cell stage, when the protein transiently translocates from its usual location in the cytoplasm to the nucleus.123 Zar1-null mutant females appear to have normal oogenesis and fertilization appears to be initiated, but the two pronuclei remain separated and most embryos arrest at the one-cell stage.125 Further, of the small percentage of embryos lacking Zar1 that survive to the two-cell stage, there is decreased expression of proteins in the transcription-requiring complex, which indicates a defect in embryonic genome activation. Whereas Zar1 is critical for progression to the two-cell stage, Mater, another protein encoded by a maternal effect gene, is expressed in oocytes and preimplantation embryo and is critical for embryonic development beyond the two-cell stage.126 Investigation into the functions of these proteins will contribute to our understanding of mechanisms that control the merging of paternal and maternal genomes, embryonic genome activation, and early embryo development.
Polarity and Cytoplasmic Reorganization
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Unlike other model organisms such as the fruit fly, the determination and establishment of cell polarity, or asymmetric distribution of cytoplasmic contents, in the mammalian oocyte and embryo is not well understood. Part of the difficulty is that although polarity in the form of an eccentric GV is observed in oocytes of some mammalian species, such as human, Rhesus monkey, bovine, and porcine, GV oocytes isolated from mouse and rat ovarian follicles do not demonstrate polarity, perhaps due to artificial effects of the in vitro culture system.127 The growing oocyte has one dominant microtubule organizing center (MTOC). The MTOC comprises centrosome, which organizes microtubules in an astral configuration. In mitotic cells, centrosomes are made up of a pair of centrioles, which are cylindrical structures containing nine triplets of microtubules that form the astral fibers required for cell division. However, centrosomes in the oocyte do not have centrioles and are thus called MTOCs. The fully grown, meiotic competent oocyte has multiple MTOCs that mediate migration of the GV from the center to an eccentric, cortical position during oocyte maturation. The eccentric position of the GV is thought to be related to or to determine the location of the meiotic spindle, which in turn determines the site of polar body extrusion.127 The eccentric position of the meiotic spindle defines the animal–vegetal axis, in which the animal pole contains the spindle-associated cortex, and the vegetal pole is characterized by clusters of endoplasmic reticulum. This asymmetric organization of the cytoplasm is thought to be critical in ensuring that both cell divisions at meiosis I and meiosis II will produce polar bodies, rather than daughter cells of equal size. This asymmetry in the generation of the egg is well conserved across species and is thought to be nature’s way of maximally conserving resources for the resulting embryo.
It is controversial whether the meiosis II cell division further determines the point of fusion between sperm and egg, the position of the first mitotic spindle, and even the spatial organization of the first mitotic division.128 The mos/MAP kinase pathway, which regulates the metaphase II arrest, is also required for transitioning the meiotic spindle from a cortical location back to the central location of a mitotic spindle.129 Therefore, determinants of oocyte polarity likely have as-yet unrecognized impact on the development and survival of the early embryo. Indeed, the cytoplasm undergoes drastic reorganization from the asymmetric oocyte and egg, to become an embryo that is capable of symmetric cell divisions.
APOPTOSIS: THE ULTIMATE CELL FATE FOR MOST OOCYTES The oocyte is perhaps the most limiting factor in human reproduction because only about 300 to 400 eggs are ovulated during a woman’s entire reproductive lifespan. In other words, more than 99.9% of all oocytes undergo programmed cell death, or apoptosis, without ever having the opportunity to become fully grown, ovulate, or fertilize. The first wave of apoptosis in the mouse model is thought to occur when germline cysts containing oogonia break down, and a similar process likely occurs in the human female fetus. The number of oocytes reaches a peak of approximately 7 million by midgestation in humans.32,130–133 Subsequently, oocytes that do not become encapsulated by granulosa cells undergo apoptosis. Further, growing follicles undergo atresia as they reach the antral stage, so that there are approximately 300,000 to 400,000 follicles at birth and about 200,000 follicles remaining by puberty.132,134,135 Although apoptosis is the most common cell fate, the initiating factor and the mechanism may differ depending on when it occurs during development. For example, the apoptosis that affects primary oocytes before their incorporation into primordial follicles is thought to be oocyte-autonomous, whereas oocytes in growing preantral and antral follicles die secondary to follicular atresia that is caused by apoptosis of the granulosa cells. Many hypotheses have been raised in an attempt to explain the high attrition rate, including that it is advantageous for the species to eliminate germ cells containing chromosomal or other errors. However, no hypothesis has been rigorously tested and the question remains open.
Environmental Factors In addition to apoptosis that is part of “normal” development, environmental factors and genetic susceptibility can exacerbate depletion of the oocyte pool, which is often manifested clinically as premature ovarian failure or early menopause. Environmental factors that have demonstrated oocyte toxicity include organochlorine chemicals from pesticides and industrial processes,136 polycyclic aromatic hydrocarbons from tobacco smoke or fuel combustion,137,138 and chemotherapeutic agents (i.e., doxorubicin) that activate the apoptotic pathway via ceramide, a lipid that is generated by acid sphingomyelinase.139 The harmful effect of ceramide is further supported by the ability of its metabolite and antagonist, sphingosine-1-phosphate, to confer protection in preventing oocytes from undergoing apoptosis when exposed to chemotherapy.140,141
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Chapter 3 Oogenesis Genetic Factors
Human Gene Mutations and Oocyte Phenotypes
Genetic mouse models of oocyte apoptosis may exhibit phenotypes varying from subfertility (i.e., small litter size or infrequent litters), premature ovarian failure, or infertility due to congenital ovarian atresia. Broadly, genetic defects may primarily be due to structural or aneuploid chromosomal abnormalities; defective X chromosome inactivation; mutation in single genes that are essential in oogenesis, folliculogenesis, or gonadogenesis; or single-gene defects affecting apoptotic pathways in the ovary. Examples of the latter are highlighted here; the other genetic abnormalities are discussed elsewhere in this book. Most importantly, apoptosis should be recognized as a common final pathway that will follow defects interfering with oogenesis. As in somatic cells, appropriate expression of pro-apoptotic proteins and those protecting against apoptosis is required to maintain the “normal” rate of attrition. Bcl-2 and Bcl-x proteins are expressed in the oocyte and granulosa cells and “protect” the oocyte from apoptosis. Although Bcl-2-deficient mice are fertile with normal litter size, there is a decrease in the number of primordial follicles as well as an increase in the number of abnormal primordial follicles that contain no oocyte or a dying oocyte.142 Similarly, Bcl-x hypomorphic mutant mice have significantly decreased numbers of primordial and primary follicles, but their phenotype is more severe and fertility is impaired.143 Therefore, these two genes are required for the maintenance of both the oocyte pool and follicular architecture. In contrast, targeted overexpression of Bcl-2 in granulosa cells results in enhanced folliculogenesis, larger litter size, and an increased incidence of germ cell tumors with age.144 Interestingly, female mice that are deficient in Bax are fertile and have significantly more primordial follicles than wild type mice even with advancing age. Further, they are able to superovulate in response to exogenous gonadotropins even at an advanced age, and these oocytes develop into viable embryos.145 Similar results were seen in the mouse model in which the proapoptotic gene caspase-2 is deleted. In addition, in the absence of caspase-2, oocytes do not undergo drug-induced apoptosis on exposure to the chemotherapeutic agent doxorubicin.146 These data support the relevance of this research area in understanding and potentially extending the female reproductive lifespan. Most importantly, understanding the regulation of apoptosis in the mammalian oocyte is vital to the development of oocyte- or follicle-sparing chemotherapeutic and other pharmaceutical agents.
Human and mouse genetic models of oocyte apoptosis may exhibit phenotypes varying from subfertility, premature ovarian failure, or infertility due to congenital ovarian atresia. Although these conditions are usually considered distinct clinical entities that are managed differently, their genetic basis may be closely related. Broadly, genetic defects may primarily be due to structural or aneuploid chromosomal abnormalities involving the X chromosome (i.e., Turner’s syndrome), defective X chromosome inactivation, and mutation or epigenetic defects involving single genes that are essential for oogenesis, folliculogenesis, or gonadogenesis. In particular, familial or de novo single-gene mutations affecting any stage of oogenesis can theoretically result in a spectrum of conditions varying from congenital ovarian dysgenesis, to premature ovarian failure, to “poor oocyte quality” identified during COH or IVF treatment. Although gene targeting in experimental mouse models has contributed significantly to our understanding of oogenesis, it is critical that we increase our effort to relate human phenotypes encountered in clinical reproductive endocrinology and infertility treatment, such as “poor ovarian response” and developmental abnormalities of oocytes and embryos, to our understanding of the mechanisms regulating oogenesis.
CLINICAL RELEVANCE AND FUTURE DIRECTIONS Many key challenges in clinical reproductive medicine today relate to the availability and function of human oocytes and the follicles that enclose them. However, we are very far from understanding what proportion of “unexplained infertility” is due to an oocyte-specific factor and even further from having any oocyte-specific treatment.147,148 Significant advances in our management of oocyte-related infertility will require a better understanding of the mechanisms through which maternal age, environmental effects, and patient-specific genetic susceptibility impact on oocyte function.
Premature Ovarian Failure Of all oocyte- or ovarian follicle-related conditions, identification of human gene mutations has thus far largely focused on familial premature ovarian failure. Using cytogenetic and fluorescent in situ hybridization techniques, familial cases of premature ovarian failure associated with balanced translocation could be studied to identify candidate genes that are disrupted by the translocation breakpoint. For example, many autosomal dominant mutations in FOXL2, a transcription factor that is expressed only in granulosa and eyelid cells, have been identified as the cause of a syndrome of premature ovarian failure and eyelid malformation called blepharophimosis ptosis epicanthus inversus syndrome.149–153 Another genetic mutation that has been linked to familial hypergonadotropic gonadal failure in humans is localized to the X-linked gene BMP15.45,154 Further, the “critical region” on the long arm of the X chromosome (Xq13-Xq26) is proposed to contain several genes that are required for oogenesis or ovary development. A familial case of premature ovarian failure has been linked to a gene located in this critical region, DIA, which is the human homolog of the Drosophila diaphanous gene that is critical for oogenesis in Drosophila.155 Because mouse homologs of FOXL2 and BMP15, as well as the D. diaphanous gene, have critical functions in oogenesis or folliculogenesis, these examples underscore the value of connecting what we learn from animal models and scenarios encountered in the clinic. Familial hypergonadotropic ovarian dysgenesis has also been identified in patients with autosomal recessive, inactivating point mutations in the FSHR gene,156–158 which presumably abrogated follicular response to FSH, resulting in atresia and premature ovarian failure. Conversely, there are also reports of various FSHR mutations that increase the sensitivity of the FSH receptor to FSH, human chorionic gonadotropin (hCG), and thyroidstimulating hormone (TSH), which led to spontaneous ovarian hyperstimulation syndrome and spontaneous superovulation.159–165
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Section 1 Basic Science These human gene mutations serve as spontaneous gene targeting models that demonstrate the role of these genes in human reproduction in vivo. Further, biochemical investigations of proteins encoded by these genes may provide insight into the pathogenesis of, and potential therapy for poor ovarian response to COH and the prevention of premature ovarian failure and ovarian hyperstimulation syndrome. In the distant (or not so distant) future, it is conceivable that as more human genetic mutations causing ovarian dysfunction are identified, genetic screening panels combined with proper counseling may help predict risks of premature “oocyte aging” to help young women with their family planning. Similarly, poor responders and patients at risk for ovarian hyperstimulation syndrome may be identified before their COH/intrauterine insemination or IVF treatment. Establishment of reliable predictors will not only help optimize cycle outcomes, but will also be valuable in counseling couples regarding their treatment options and risks of multiple gestation and ovarian hyperstimulation syndrome.
Aneuploidy Abnormal chromosomal segregation in meiosis results in aneuploidy, which increases in incidence with advancing maternal age in humans. Aneuploidy, considered “the most important problem in human reproduction,” affects an estimated 25% to 50% of human eggs, accounts for at least 35% of spontaneous abortions and approximately 4% of stillbirths, and is the leading genetic cause of congenital mental retardation and developmental disabilities.166–172 The key risk factors for maternally derived aneuploidy in humans are maternal age and susceptible patterns of meiotic recombination, such as recombination sites that are close to the centromere or the telomere (reviewed in Lamb and colleagues173). Compared to the mouse model, there is an extreme variability in the location of recombination nodules in human oocytes,26 which may explain the high rates of aneuploidy in our eggs and embryos. However, although susceptible locations of recombination nodules are thought to be the main risk factor in young women, they do not explain the high aneuploidy rates seen with increasing maternal age.173 In fact, the association between these recombination patterns and aneuploidy decreases with increasing age. Therefore, as-yet undefined recombination-independent factors are proposed to be risk factors for older women.173
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IVF allows us to see the entire developmental process from GV, GVBD, to metaphase II arrest, formation of the one-cell embryo with two pronuclei, all the way to the blastocyst stage. Although we expect to see some abnormal oocytes or embryos during IVF treatment, when an unusual oocyte or embryo phenotype is consistently observed in the same couple, especially if they have “unexplained infertility,” we are alerted to the possibility that those abnormalities may be related to the underlying cause of the couple’s infertility. Repeated IVF treatment failure in these patients would further identify them as the patient population that may benefit from having a molecular diagnosis and nonempirical treatment that specifically targets the molecular diagnosis. For example, recurrent
or familial cases of zona pellucida abnormalities,174 maturation arrest,175–179 parthenogenetic activation,180 triploidy,181 abnormal fertilization,182 abnormal cell division in meiosis II,183 and empty follicle syndrome184,185 have been reported. Indeed, the development of molecular diagnosis and treatment for this subset of patients is a major challenge in reproductive medicine.
FUTURE DIRECTIONS Outcome-based, systematic surveys of human oocyte and embryo phenotypes encountered in IVF treatment are critical in guiding clinicians and scientists to focus on conditions that are prevalent and relevant in patients seeking infertility treatment. Further, although mammalian oocyte biology research has traditionally been based on the candidate gene approach, complementary experimental strategies by more unbiased, forward genetic methods such as random chemical mutagenesis of the mouse genome followed by screening for infertility phenotype has begun to uncover novel genes that have critical functions in oogenesis.186 Newly identified genes with potentially critical functions in oogenesis can then be further studied by various gene targeting techniques. Another forward genetic approach is chemical genetics in the form of high throughput small molecule (SM) library screening of processes such as oocyte maturation and follicular development. SM library screening followed by functional experiments have led to the identification of lead compounds in drug discovery and the identification of novel proteins in other areas of research.187–189 Although the technical challenges involved in the high throughput experimentation of the oocyte or follicle may seem quite overwhelming, they may not be truly insurmountable. We can look beyond medicine and biology, and engage bioengineers to bring microfluidics and other microsystems-based technologies to help us accelerate discovery in the field of oocyte biology and infertility.190 Such interdisciplinary effort will be instrumental in giving us the ability to treat or prevent oocyte-related reproductive problems. It will also facilitate the development of oocyte- or fertility-sparing pharmaceuticals and the identification of environmental aneugens to direct preventive strategies to preserve reproductive health. New findings on functions and human mutations of ovarian genes can be searched online on several databases, including the Ovarian Kaleiodoscope (http://ovary.stanford.edu/) and Online Mendelian Inheritance in Man (OMIM) (http://www.ncbi. nlm.nih.gov/entrez/query.fcgi?db=OMIM),191 OMIM and Online Mendelian Inheritance in Man are trademarks of the Johns Hopkins University.
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During prophase of meiosis I, oocytes undergo DNA replication, homologous pairing, synapse, and recombination, but then remain arrested at the diplotene stage of prophase I until sexual maturity. Primordial germ cells are derived extragonadally from the yolk sac endoderm. They migrate from the base of the allantois to the genital ridges. Members of the TGF superfamily of growth factors are important signaling molecules for the migration and survival of primordial germ cells.
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Primordial germ cells differentiate into oogonia, which are sexually differentiated germ cells. Oogonia become oocytes by entering into prophase of meiosis I. Primordial follicles are diplotene-arrested oocytes surrounded by a single layer of flattened granulosa cells. Primary follicles are characterized by a single layer of cuboidal granulosa cells. Prophase I has four stages: leptotene, zygotene, pachytene, and diplotene. The transition from pachytene to diplotene marks the beginning of folliculogenesis. Oocytes arrest at the diplotene stage, when homologous chromosomes are held together at chiasmata. The oocyte is surrounded by the zona pellucida, which is composed of four proteins (ZP) in the human. ZP2 and ZP3 mediate sperm binding. Members of the family of TGF proteins are critical regulators of follicular development. The recruited growing follicles are primary follicles. Antral follicles tend to undergo atresia unless rescued by FSH.
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Antimüllerian hormone is expressed in granulosa cells of growing follicles. Preantral follicle growth is regulated predominantly by paracrine and autocrine signals. Gonadotropins are required for antrum formation. Follicular growth from primary and secondary follicles to antral stages takes several months. The cumulus cells are specialized granulosa cells that line the oocyte and have important functions in oocyte development, including meiotic arrest and induction of ovulation. LH triggers ovulation by the cumulus cell compartment and release of the oocyte from meiotic arrest. The first observable change of resumption of meiosis is germinal vesicle breakdown. Achievement of metaphase I and the metaphase–anaphase transition depends on the formation of an intact meiotic spindle. Genomic imprinting mediates pre-designated, differential silencing of the maternal and paternal alleles. More than 99% of all oocytes undergo programmed cell death (apoptosis).
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150. Crisponi L, Deiana A, Loi A, et al: The putative forkhead transcription factor FOXL2 is mutated in blepharophimosis/ptosis/epicanthus inversus syndrome. Nat Genet 27:159–166, 2001. 151. De Baere E, Beysen E, Oley C, et al: FOXL2 and BPES: Mutational hotspots, phenotypic variability, and revision of the genotype–phenotype correlation. Am J Hum Genet 72:478–487, 2003. 152. Schmidt D, Ovitt C, Anlag K, et al: The murine winged-helix transcription factor Foxl2 is required for granulosa cell differentiation and ovary maintenance. Development 131:933–942, 2004. 153. Udar N, Yellore V, Chalukya M, et al: Comparative analysis of the FOXL2 gene and characterization of mutations in BPES patients. Hum Mutat 22:222–228, 2003. 154. Di Pasquale E, Beck-Peccoz P, Persani L: Hypergonadotropic ovarian failure associated with an inherited mutation of human bone morphogenetic protein-15 (BMP15) gene. Am J Hum Genet 75:106–111, 2004. 155. Bione S, Sala C, Manzini C, et al: A human homologue of the Drosophila melanogaster diaphanous gene is disrupted in a patient with premature ovarian failure: Evidence for conserved function in oogenesis and implications for human sterility. Am J Hum Genet 62:533–541, 1998. 156. Aittomaki K, Herva R, Stenman U, et al: Clinical features of primary ovarian failure caused by a point mutation in the follicle-stimulating hormone receptor gene. J Clin Endocrinol Metab 81:3722–3726, 1996. 157. Aittomaki K, Dieguez Lucena JL, Pakarinen P, et al: Mutation in the follicle-stimulating hormone receptor gene causes hereditary hypergonadotropic ovarian failure. Cell 82:959–968, 1995. 158. Doherty E, Pakarinen P, Tiitinen A, et al: A novel mutation in the FSH receptor inhibiting signal transduction and causing primary ovarian failure. J Clin Endocrinol Metab 87:1151–1155, 2002. 159. Delbaere A, Smits G, Olatunbosun O, et al: New insights into the pathophysiology of ovarian hyperstimulation syndrome. What makes the difference between spontaneous and iatrogenic syndrome? Hum Reprod 19:486–489, 2004. 160. Olatunbosun OA, Gilliland B, Brydon LA, Chizen DR: Spontaneous ovarian hyperstimulation syndrome in four consecutive pregnancies. Clin Exp Obstet Gynecol 23:127–132, 1996. 161. Smits G, Olatunbosun O, Delbaere A, et al: Ovarian hyperstimulation syndrome due to a mutation in the follicle-stimulating hormone receptor. NEJM 349:760–766, 2003. 162. Vasseur C, Rodien P, Beau I, et al: A chorionic gonadotropin-sensitive mutation in the follicle-stimulating hormone receptor as a cause of familial gestational spontaneous ovarian hyperstimulation syndrome. NEJM 349:753–759, 2003. 163. Al-Hendy A, Moshynska O, Saxena A, Feyles V: Association between mutations of the follicle-stimulating-hormone receptor and repeated twinning. Lancet 356:914, 2000. 164. Gromoll J, Simoni M: Follicle-stimulating-hormone receptor and twinning. Lancet 357:230–232, 2001. 165. Montgomery GW, Duffy D, Hall J, et al: Mutations in the folliclestimulating hormone receptor and familial dizygotic twinning. Lancet 357:773–774, 2001. 166. Hassold TJ, Hunt PA: To err (meiotically) is human: The genesis of human aneuploidy. Nat Gen 2:280–291, 2001. 167. Hodges CA, LeMaire-Adkins R, Hunt PA: Coordinating the segregation of sister chromatids during the first meiotic division: Evidence for sexual dimorphism. J C Sci 114:2417–2426, 2001. 168. Hunt PA, Hassold TJ: Sex matters in meiosis. Science 296:2181–2183, 2002. 169. LeMaire-Adkins R, Radke K, Hunt PA: Lack of checkpoint control at the metaphase/anaphase transition: A mechanism of meiotic nondisjunction in mammalian females. J Cell Biol 139:1611–1619, 1997. 170. Hassold T, Chiu D: Maternal age-specific rates of numerical chromosome abnormalities with special reference to trisomy. Hum Genet 70:11–17, 1985. 171. Risch N, Stein Z, Kline J, Warburton D: The relationship between maternal age and chromosome size in autosomal trisomy. Am J Hum Genet 39:68–78, 1986.
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Chapter 3 Oogenesis 172. Morton NE, Jacobs PA, Hassold T, Wu D: Maternal age in trisomy. Ann Hum Genet 52:227–235, 1988. 173. Lamb NE, Yu K, Shaffer J, et al: Association between maternal age and meiotic recombination for trisomy 21. Am J Hum Genet 76:91–99, 2005. 174. Alikani M, Noyes N, Cohen J, Rosenwaks Z: Monozygotic twinning in the human is associated with the zona pellucida architecture. Hum Reprod 9:1318–1321, 1994. 175. Bergere M, Lombroso R, Gombault M, et al: An idiopathic infertility with oocytes metaphase I maturation block: Case report. Hum Reprod 16:2136–2138, 2001. 176. Combelles CM, Albertini DF, Racowsky C: Distinct microtubule and chromatin characteristics of human oocytes after failed in-vivo and in-vitro meiotic maturation. Hum Reprod 18:2124–2130, 2003. 177. Levran D, Farhi J, Nahum H, et al: Maturation arrest of human oocytes as a cause of infertility: Case report. Hum Reprod 17:1604–1609, 2002. 178. Neal MS, Cowan L, Louis JP, et al: Cytogenetic evaluation of human oocytes that failed to complete meiotic maturation in vitro. Fertil Steril 77:844–845, 2002. 179. Schmiady H, Neitzel H: Arrest of human oocytes during meiosis I in two sisters of consanguineous parents: First evidence for an autosomal recessive trait in human infertility: Case report. Hum Reprod 17:2556–2559, 2002. 180. Oliveira FG, Dozortsev D, Diamond M, et al: Evidence of parthenogenetic origin of ovarian teratoma: Case report. Hum Reprod 19:1867–1870, 2004. 181. Pal L, Toth TL, Leykin L, Isaacson KB: High incidence of triploidy in in-vitro fertilized oocytes from a patient with a previous history of
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recurrent gestational trophoblastic disease. Hum Reprod 11:1529–1532, 1996. van der Westerlaken L, Helmerhorst F, Verburg H, Naaktgeboren N: Successful intracytoplasmic sperm injection after failed in vitro fertilization due to multipronuclear oocytes. Fertil Steril 80:639–640, 2003. Hardarson T, Lundin K, Hanson C: A human oocyte with two sets of MII/PB-structures. Hum Reprod 17:1892–1894, 2002. La Sala GB, Ghirardini G, Cantarelli M, et al: Recurrent empty follicle syndrome. Hum Reprod 6:651–652, 1991. Onalan G, Pabuçcu R, Önalan R, et al: Empty follicle syndrome in two sisters with three cycles: Case report. Hum Reprod 18:1864–1867, 2003. Handel MA, Lessard C, Reinholdt L, et al: Mutagenesis as an unbiased approach to identify contraceptive targets. Mol Cell Endocrinol 250:201–205, 2006. Yarrow JC, Feng Y, Perlman ZE, et al: Phenotypic screening of small molecule libraries by high throughput cell imaging. Comb Chem High Throughput Screen 6:279–286, 2003. Ding S, Wu T, Brinker A, et al: Synthetic small molecules that control stem cell fate. Proc Natl Acad Sci USA 100:7632–7637, 2003. Cheung A, Dantzig JA, Hollingworth S, et al: A small-molecule inhibitor of skeletal muscle myosin II. Nat Cell Biol 4:83–88, 2002. Walker GM, Zeringue HC, Beebe DJ: Microenvironment design considerations for cellular scale studies. Lab Chip 4:91–97, 2004. Pederson T, Peters H: Proposal for a classification of oocytes and follicles in the mouse ovary. J Reprod Fertil 17:555–557, 1968.
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4
Physiology of Male Gametogenesis Rakesh K. Sharma
INTRODUCTION
SUPPORTING CELLS
The contribution of the male to the biology of reproduction is to produce a genetically intact spermatozoa that will fertilize an oocyte. The end product of male gametogenesis, the mature spermatozoa, is designed for one purpose: to deliver the male contribution of the genetic makeup to the embryo. The biology of gamete production is different in males compared to females. Gamete production in females is intimately part of the endocrine responsibility of the ovary. If there are no gametes, then hormone production is drastically curtailed. Depletion of oocytes implies depletion of the major hormones of the ovary. In the male this is not the case. Androgen production will proceed normally without a single spermatozoa in the testes. This chapter reviews some of the basic structural morphology of the testes and the process of development to obtain mature spermatozoa.
The supporting cells of the testes refer to cells that are part of the cellular development that leads to a mature sperm. They are, however, extremely important to sperm production and spermatogenesis would be impossible without them. The two most important cells are the Leydig and Sertoli cells.
ORGANIZATION OF THE TESTES The testes are ellipsoid in shape, measuring 2.5 × 4 cm in diameter and engulfed by a capsule (tunica albuginea) of strong connective tissue.1 Along its posterior border, the testis is loosely connected to the epididymis, which gives rise to the vas deferens at its lower pole.2 The testis has two main functions: it produces hormones, in particular testosterone, and it produces the male gamete—the spermatozoa. The testis is incompletely divided into a series of lobules. Most of the volume of the testis is made up of seminiferous tubules, which are looped or blind-ended and packed in connective tissue within the confines of the fibrous septa (Fig. 4-1). The fibrous septae divide the parenchyma into about 370 conical lobules consisting of the seminiferous tubules and the intertubular tissue. The seminiferous tubules are separated by groups of Leydig cells, blood vessels, lymphatics, and nerves. The seminiferous tubules are the site of sperm production (see Fig. 4-1). The wall of each tubule is made up of myoid cells of limited contractility and also of fibrous tissue. Each seminiferous tubule is about 180 μm in diameter; the height of the germinal epithelium measures 80 μm, and the thickness of the peritubular tissue is about 8 μm.3 The germinal epithelium consists of cells at different stages of development located within the invaginations of Sertoli cells, namely spermatogonia, primary and secondary spermatocytes, and spermatids. Both ends of the seminiferous tubules open into the spaces of the rete testis4 (see Fig. 4-1). The fluid secreted by the seminiferous tubules is collected in the rete testis and delivered in the ductal system of the epididymis.
Leydig Cells The Leydig cells are irregularly shaped cells with granular cytoplasm present individually or more often in groups within the connective tissue.5,6 Leydig cells are the prime source of the male sex hormone testosterone.7–9 The pituitary hormone luteinizing hormone (LH) acts on Leydig cells to stimulate the production of testosterone. This acts as a negative feedback on the pituitary to suppress or modulate further LH secretion.8 Compared with the testosterone levels in the blood, the intratesticular concentration of testosterone is many times higher, especially near the basement membrane of the seminiferous tubule.
The Sertoli Cell The seminiferous tubules are lined with highly specialized Sertoli cells that rest on the tubular basement membrane and extend into the lumen with a complex ramification of cytoplasm (Fig. 4-2). Spermatozoa are produced at puberty but are not recognized by the immune system that develops during the first year of life. The seminiferous tubule space is divided into basal (basement membrane) and luminal (lumen) compartments by strong intercellular junctional complexes called tight junctions. These anatomic arrangements, complemented by closely aligned myoid cells that surround the seminiferous tubule, form the basis for the blood–testis barrier. The blood–testis barrier provides a microenvironment for spermatogenesis to occur in an immunologically privileged site. Sertoli cells serve as “nurse” cells for spermatogenesis, nourishing germ cells as they develop. These also participate in germ cell phagocytosis. Multiple sites of communication exist between Sertoli cells and developing germ cells for the maintenance of spermatogenesis within an appropriate hormonal milieu. Follicle-stimulating hormone (FSH) binds to the high-affinity FSH receptors found on Sertoli cells, signaling the secretion of androgen-binding protein. High levels of androgens are also present within the seminiferous tubule. The two most important hormones secreted by the Sertoli cells are antimüllerian hormone and inhibin. Antimüllerian hormone is a critical component of embryonic development and
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Ligamentus remnant of processus vaginalis
Head of epididymis
Efferent ductules
Vas deferens
Straight tubule
Rete testis in mediast
Seminiferous tubule
Body of epididymis Capsule (tunica albuginea)
Parietal layer Tunica vaginalis
Tail of epididymis
Head 4 μm
Cavity Visceral layer
Acrosomal cap
Nucleus Neck 0.3 μm Centriole Middle piece 7 μm Spiral mitochondria
Axoneme
Principal piece 40 μm
End piece 5-7 μm
Figure 4-1 This cross-section through the testicle shows the convoluted seminiferous tubules and interstitial tissue. The epithelium of the convoluted tubules has sperm in various stages of maturation (inset) and the Sertoli cells. Mature but immobile sperm are released into the lumen. A magnified view of a mature spermatozoon is seen. Diagrammatic representation of the human spermatozoon showing the acrosome, the nucleus and nuclear envelopes, the mitochondrial sheath of the midpiece, the principal piece, and the end piece.
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is involved in the regression of the müllerian ducts. Inhibin is a key macromolecule in pituitary FSH regulation. Some of the functions of the Sertoli cell are (1) maintenance of integrity of seminiferous epithelium, (2) compartmentalization of seminiferous epithelium, (3) secretion of fluid to form tubular lumen to transport sperm within the duct, (4) participation in spermiation, (5) phagocytosis and elimination of cytoplasm, (6) delivery of nutrients to germ cells, (7) steroidogenesis and steroid metabolism, (8) movement of cells within the epithelium, (9) secretion of inhibin and androgen-binding protein, (10) regulation of spermatogenic cycle, and (11) provision of a target
for hormones LH, FSH, and testosterone receptors present on Sertoli cells.
SPERMATOGENESIS The process of differentiation of a spermatogonium into a spermatid is known as spermatogenesis.4 It is a complex, temporal event whereby primitive, totipotent stem cells divide to either renew themselves or produce daughter cells that become specialized testicular spermatozoa over a span of weeks. Spermatogenesis involves both mitotic and meiotic proliferation
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Chapter 4 Physiology of Male Gametogenesis Lumen Elongated spermatid Round spermatid
Spermatocyte
Sertoli cell
Spermatogonia
Lamina propria
Figure 4-2 Section of the germinal epithelium in the seminiferous tubule. Semithin section drawing × 900. Sertoli cells divide the germinal epithelium into basal and luminal compartments. (Adapted from Holstein A-F, Schulze W, Davidoff M: Understanding spermatogenesis is a prerequisite for treatment. Reproductive Biology and Endocrinology. BioMed Central Ltd., 2003).
as well as extensive cell remodeling. Spermatogenesis can be divided into three major phases: (1) proliferation and differentiation of spermatogonia, (2) meiosis, and (3) spermiogenesis, a complex metamorphosis that transforms round spermatids arising from the final division of meiosis into a complex structure called the spermatozoon. In humans, the process of spermatogenesis starts at puberty and continues throughout the entire lifespan of the individual. It takes place in the lumen of the seminiferous tubules. In fact, 90% of the testis volume is determined by the seminiferous tubules and their constituent germ cells at various stages of development. Once the gonocytes have differentiated into fetal spermatogonia, an active process of mitotic replication is initiated very early in embryonic development. This appears to be under FSH control and develops the baseline number of precursor cells of the testicle.
Proliferation and Differentiation of Spermatogonia Within the seminiferous tubule, germ cells are arranged in a highly ordered sequence from the basement membrane to the lumen (see Fig. 4-2). Spermatogonia lie directly on the basement membrane, followed by primary spermatocytes, secondary spermatocytes, and spermatids as they progress toward the tubule lumen. The tight junction barrier supports spermatogonia and early spermatocytes within the basal compartment and all subsequent germ cells within the luminal compartment.
Types of Spermatogonia
Spermatogonia represent a population of cells that divide by mitosis, providing both a renewing stem cell population as well as spermatogonia that are committed to enter the meiotic process. Germ cells are staged by their morphologic appearance; there are dark type A (Adark) and pale type A (Apale) and type B spermatogonia, primary spermatocytes (preloptotene, leptotene, zygotene, and pachytene), secondary spermatocytes, and spermatids (Sa, Sb, Sc, Sd1, and Sd2) (Fig. 4-3). Other proliferative spermatogonia include Apaired (Apr), resulting from dividing Aisolated (Ais), and subsequently dividing to form Aaligned (Aal). Differentiated spermatogonia include type A1, A2, A3, A4, intermediate, and type B, each a result of the cellular division of the previous type. In humans, four spermatogonial cell types have been identified; these are Along, Adark, Apale, and B.10–12 In the rat, type Ais is believed to be the stem cell13,14; however, it is not clear which human type A spermatogonia is the stem cell. Some investigators have proposed that the type Adark spermatogonia represent the reserve or nonproliferative spermatogonial population that gives rise to Apale.11,15,16 Spermatogonia do not separate completely after meiosis but remain joined by intercellular bridges, which persist throughout all stages of spermatogenesis and are thought to facilitate biochemical interactions, allowing synchrony of germ cell maturation.17 Type B spermatogonia possess considerably more chromatin within the inner nuclear envelope than intermediate or type A spermatogonia. Type B spermatogonia represent the cells that differentiate and enter into the process of meiosis during which they are called primary spermatocytes.11 They are the differential precursors to preleptotene spermatocytes. This last mitotic division helps maintain a pool of stem cells so the process can continue indefinitely.
Spermatocytogenesis The purpose of spermatogenesis is to produce genetic material necessary for the replication of the species through mitosis and meiosis. Spermatocytogenesis takes place in the basal compartment. Primary spermatocytes enter the first meiotic division to form secondary spermatocytes. Prophase of the first meiotic division is very long, and the primary spermatocyte has the longest lifespan. Secondary spermatocytes undergo the second meiotic division to produce spermatids. Secondary spermatocytes are short-lived (1.1 to 1.7 days). The meiotic phase involves primary spermatocytes until spermatids are formed; during this process, chromosome pairing, crossover, and genetic exchange is accomplished until a new genome is determined. In turn, a postmeiotic phase involving spermatids all the way up to spermatozoa develops, ending in the formation of the specialized cell. The process by which spermatids become mature spermatozoa can take several weeks and is one of the most elaborate differentiation events of any mammalian cell. This process requires the synthesis of hundreds of new proteins and the assembly of unique organelles. Within the purview of the Sertoli cell, several events occur during this differentiation of spermatid to sperm.
Mitosis Mitosis involves proliferation and maintenance of spermatogonia. It is a precise, well-orchestrated sequence of events
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Section 1 Basic Science Spermatogenesis Stem cells Along
Apale
Adark 2N Diploid chromosome content
Differentiating spermatogonia
B 2N
Meiotic division
Spermatocytes P-L
L
Z
P 1N
Spermiogenesis
Spermiation Haploid chromosome content
Spermatids 1N SA
Sb1
Sb2
Sc
Sd1
Sd2
Figure 4-3 A diagrammatic representation of spermatogenesis, spermiogenesis, and spermiation during which the developing germ cells undergo mitotic and meiotic division to reduce the chromosome content. (Adapted from Huckins C: Adult spermatogenesis. Characteristics, kinetics, and control. In Lipshultz LI,Howards SS (eds): Infertility in the Male. New York, Churchill Linvingstone, 1975, p 108.)
involving duplication of the genetic material (chromosomes), breakdown of the nuclear envelope, and equal division of the chromosomes and cytoplasm into two daughter cells.18,19 DNA is also spatially organized into loop domains on which specific regulatory proteins interact during cellular replication.19–24 The mitotic phase involves spermatogonia (types A and B) and primary spermatocytes (spermatocytes I). Developing germ cells interconnected by intracellular bridges produce the primary spermatocyte through a series of mitotic divisions. Once the baseline number of spermatogonia is established after puberty, the mitotic component will proceed in order to continue to provide precursor cells and to start the process of differentiation and maturation.
Meiosis
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Meiosis is a complex process with specific regulatory mechanisms of its own.25 The process commences when type B spermatogonia lose their contact with the basement membrane to form preleptotene primary spermatocytes. Thus, each primary spermatocyte can theoretically yield four spermatids, although fewer actually result, because some germ cells are lost due to the complexity of meiosis. The primary spermatocytes are the largest germ cells of the germinal epithelium. Meiosis is characterized by prophase, metaphase, anaphase, and telophase. In this, two successive cell divisions yield four haploid spermatids from one diploid primary spermatocyte. As a consequence, the daughter cells contain only half of the chromosome content of the parent cell. After the first meiotic
division (reduction division), each daughter cell contains one partner of the homologous chromosome pair, and they are called secondary spermatocytes. These cells rapidly enter the second meiotic division (equational division), in which the chromatids then separate at the centromere to yield haploid early round spermatids. Meiosis assures genetic diversity and involves primary and secondary spermatocytes, which give rise to spermatids.
Spermiogenesis Spermiogenesis is a process during which the morphologic changes occur during the differentiation of the spermatid into the spermatozoon. It begins once the process of meiosis is completed. Six different stages have been described in the process of spermatid maturation in humans: Sa-1 and Sa-2, Sb-1 and Sb-2, and Sc-1 and Sc-2 (see Fig. 4-3). Each of these stages can be identified by morphologic characteristics. During the Sa-1 stage, both the Golgi complex and mitochondria are well developed and differentiated, the acrosomal vesicle appears, the chromatid body develops in one pole of the cell opposite from the acrosomal vesicle, and the proximal centriole and the axial filament appears. During Sb-1 and Sb-2 stages, acrosome formation is completed, the intermediate piece is formed, and the tail develops. This process is completed during the Sc stages. During the postmeiotic phase, progressive condensation of the nucleus occurs with inactivation of the genome, the histones are converted into transitional proteins, and finally protamines are converted into well-developed disulfide bonds.
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Chapter 4 Physiology of Male Gametogenesis Spermiation The process whereby a mature spermatid frees itself from the Sertoli cell and enters the lumen of the tubule as a spermatozoon is known as spermiation. The spermatids originating from the same spermatogonia remain connected by bridges to facilitate the transport of cytoplasmic products. Spermiation involves the active participation of the Sertoli cell. This may also involve actual cell movement as the spermatids advance toward the lumen of the seminiferous tubules.26 The mature spermatids close their intracellular bridges, disconnect their contact to the germinal epithelium, and become free cells called spermatozoa. Portions of the cytoplasm of the Sertoli cell known as the cytoplasmic droplet may remain as part of the spermatozoon during the process of spermiation. This is a morphologic feature present on immature sperm in semen.27
The Cycle or Wave of Seminiferous Epithelium A cycle of spermatogenesis involves the division of primitive spermatogonial stem cells into subsequent germ cell types through the process of meiosis. Type A spermatogonial divisions occur at a shorter time interval than the entire process of spermatogenesis. Therefore, at any given time, several cycles of spermatogenesis coexist within the germinal epithelium. In humans, spermatocyte maturation takes 25.3 days, spermiogenesis 21.6 days, and the total estimated time for spermatogenesis is 74 days. Spermatogenesis is not random throughout the seminiferous epithelium. Germ cells are localized in spatial units referred to as stages and represent consistent associations of germ cell steps.28–31 In rodent spermatogenesis, one stage can be found in a crosssection of seminiferous tubule. Each stage is recognized by development of the acrosome, meiotic divisions and shape of the nucleus, and release of the sperm into the lumen of the seminiferous tubule. A stage is designated by Roman numerals. Each cell type of the stage is morphologically integrated with the others in its development process. Each stage has a defined morphologic entity of spermatid development, called a step, designated by an Arabic number. Several steps occur together to form a stage, and several stages are necessary to form a mature sperm from immature stem cells. Within any given cross-section of the seminiferous tubule there are four or five layers of germ cells. Cells in each layer comprise a generation; a cohort of cells that develop as a synchronous group and each has a similar appearance and function. Stages I to III have four generations comprising type A spermatogonia, two primary spermatocytes, and an immature spermatid. Stages IV to VIII have five generations: type A spermatogonia, one generation of primary spermatocytes, one generation of secondary spermatocytes, and one generation of spermatids. The cycle of spermatogenesis can be identified for each species, but the duration of the cycle varies.11 The stages of spermatogenesis are sequentially arranged along the length of the tubule. This arrangement of the stages of spermatogenesis is such that it results in a “wave of spermatogenesis” along the tubule. This wave is in space but the cycle is in time.31 Along the length of the seminiferous tubule there are only certain crosssections where spermatozoa are released. In the rat, all stages are involved in spermatogenesis, but spermatozoa are released only in stage VIII.
Although it appears that the spatial organization is lacking or poor in the human seminiferous tubule, mathematic modeling indicates that these stages are tightly organized in an intricate spiral pattern.32 In addition to the steps being organized spatially within the seminiferous tubule, the stages are organized in time.31 Thus a position in the tubule that is occupied by cells comprising stage I will become stage II, followed by stage III, until the cycle repeats. In humans, the duration of the cycle is 16 days and the progression from spermatogonia to spermatozoa takes 70 days, or four and a half cycles of the seminiferous cycle. During spermatogenesis, cytoplasmic bridges link cohorts of germ cells that are at the same point in development, and these cells pass through the process together. Groups of such cells at different stages can be observed histologically on cross-section and many germ cell cohorts are seen only in association with certain other germ cells. This has led to the description of six stages of the seminiferous tubule epithelium in men. To add another level of complexity, the steps of the spermatogenic cycle within the space of the seminiferous tubules demonstrate a specific organization, termed spermatogenic waves. In humans, this wave appears to describe a spiral cellular arrangement as one progresses down the tubule. This spatial arrangement probably exists to ensure that sperm production is a continuous rather than a pulsatile process.
Efficiency of Spermatogenesis Spermatogenetic efficiency varies between different species but appears to be relatively constant in man. The time for the differentiation of a spermatogonium into a mature spermatid is estimated to be 70 ± 4 days.33 In comparison to animals the spermatogenetic efficiency in man is poor. The daily rate of spermatozoa production is calculated at 3 to 4 million per gram of testicular tissue.34 A higher number of spermatozoa should be expected in the ejaculate than the 20 million/mL described by the World Health Organization.35 A majority of the cells developed (>75%) are lost as a result of apoptosis or degeneration; of the remaining, more than half are abnormal. Therefore, only about 12% of the spermatogenetic potential is available for reproduction.36 An age-related reduction in daily sperm production in men, which is associated with a loss of Sertoli cells, is also seen. This may result from an increase in germ cell degeneration during prophase of meiosis or from loss of primary spermatocytes. There is also a reduction in the number of Leydig cells, non-Leydig interstitial cells, myoid cells, and Sertoli cells. The process of spermiation and the journey of a sperm through the ductus deferens of the testis to a site where it can be included in the ejaculate are thought to take a further 10 to 14 days. It is a lengthy process, and quantitative changes in sperm production may take some time to become apparent in a sample of semen. The nucleus progressively elongates as its chromatin condenses. The head is characterized by a flattened and pointed paddle shape, specific to each species. This process involves the Golgi phase, cap phase, acrosomal phase, and maturation phase. Golgi Phase
The Golgi complex forms a caplike structure called the acrosome. The centrioles migrate from the cytoplasm to the base of the nucleus. The proximal centriole becomes the implantation
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Section 1 Basic Science apparatus to anchor the flagellum to the nucleus. The distal centriole becomes the axoneme. Cap Phase
The acrosome forms a distinct cap over nucleus. The acrosome is formed from the Golgi complex. As the Golgi complex moves away from the nucleus, a flagellum is constructed from the centriole. Acrosomal Phase
The formation of the acrosome starts with the coalescence of a series of granules from the Golgi complex, which migrates to come into contact with the nuclear membrane, where it covers like a caplike structure over 30% to 50% of the nuclear surface.37 The acrosome covers the nucleus and contains the hydrolytic enzymes necessary for fertilization. The manchette is formed, and the spermatids are embedded in Sertoli cells. Maturation Phase
Mitochondria migrate toward the segment of the growing tail to form the mitochondrial sheath. Dense outer fibers and a fibrous sheath are formed and this completes assembly of the tail. The bulk of the spermatid cytoplasm is eventually discarded as a residual body. The spermatid is now called a spermatozoon. As spermiogenesis proceeds, the spermatid moves toward the lumen of the seminiferous tubule. With completion of spermatid elongation, the Sertoli cell cytoplasm retracts around the developing sperm, stripping it of all unnecessary cytoplasm and extruding it into the tubule lumen. The mature sperm has remarkably little cytoplasm left after extrusion. The mature spermatozoon is an elaborate, highly specialized cell produced in massive quantity, up to 300 per g of testis per second.
SPERMATOZOA Spermatozoa are highly specialized and condensed cells that do not grow or divide. A spermatozoon consists of the head, containing the paternal material (DNA), and the tail, which provides motility (see Fig. 4-1). The spermatozoon is endowed with a large nucleus but lacks the large cytoplasm characteristic of most body cells. Men are unique in the morphologic heterogeneity of the ejaculate.38–40
Head The heads of stained spermatozoa are slightly smaller than heads of living spermatozoa in the original semen.41 The normal head is oval, measuring about 4.0 to 5.5 μm in length and 2.5 to 3.5 μm in width. The normal length-to-width ratio is about 1.50 to 1.70.41 Under bright field illumination, the most commonly observed aberrations include head shape/size defects, including large, small, tapering, piriform, amorphous, vacuolated (>20% of the head surface occupied by unstained vacuolar areas), and double heads, or any combination of these defects.42
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The acrosome is represented by the Golgi complex and covers about two thirds of the anterior head area.39,40,42 The apical thickening seen in many other species is missing; however, the
acrosome shows a uniform thickness/thinning toward the equatorial segment and covers about 40% to 70% of the sperm head. When observed under the scanning electron microscope, a furrow that completely encircles the head (i.e., acrosomal and postacrosomal regions) divides the sperm head unequally. An equatorial segment that is followed by the postacrosomal region is not very clearly visible on scanning electron microscope. The maximal thickness and width of the spermatozoon is seen in the postacrosomal region. Under the electron microscope the sperm head is a flattened ovoid structure consisting primarily of the nucleus. The acrosome is a caplike structure covering the anterior two thirds of the sperm head, which arises from the Golgi complex of the spermatid as it differentiates into a spermatozoon. The acrosome contains several hydrolytic enzymes, including hyaluronidase and proacrosin, which are necessary for fertilization.38 During fertilization of the egg, the fusion of the outer acrosomal membrane with the plasma membrane at multiple sites releases the acrosomal enzymes at the time of the acrosome reaction. The anterior half of the head is devoid of plasma and an outer acrosomal membrane and is covered only by the inner acrosomal membrane.43 The posterior region of the sperm head is covered by a single membrane called the postnuclear cap. The overlap of the acrosome and the postnuclear cap results in an equatorial segment, which does not participate in the acrosome reaction. The nucleus, comprising 65% of the head, is composed of DNA conjugated with protein. The chromatin is tightly packed, and no distinct chromosomes are visible. The genetic information, including the sex-determining X or Y chromosome, is coded and stored in the DNA.38
Neck This forms a junction between head and tail. It is fragile and the presence of decapitated spermatozoa is a common abnormality.
Tail The sperm tail arises at the spermatid stage. The centriole during spermatogenesis is differentiated into three parts: midpiece, the main or principal piece, and endpiece. The mitochondria reorganize around the midpiece. An axial core comprising of two central fibrils is surrounded by a concentric ring of nine double fibrils, which continue to the end of the tail. The additional outer ring is comprised of nine coarse fibrils. The principal piece is comprised of nine coarse outer fibrils diminishing in thickness and finally only the inner 11 fibrils of the axial core surrounded by a fibrous sheath. The mitochondrial sheath of the midpiece is relatively short but slightly longer than the combined length of the head and neck.38
Endpiece The endpiece is not distinctly visible by light microscopy. Both tail sheath and coarse filaments are absent. The tail, containing all the motility apparatus, is 40 to50 μm long and arises from the spermatid centriole. It propels by waves that are generated in the neck region and pass distally along like a whiplash. Under bright field illumination, common neck and midpiece aberrations include their absence, bent tails, distended or irregular/
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Chapter 4 Physiology of Male Gametogenesis bent midpiece, abnormally thin midpiece (no mitochondrial sheath), or any of these combinations.42 Tail aberrations include short, multiple, hairpin, and broken tails; tails of irregular width; coiling tails with terminal droplets; or any of these combinations.42 Cytoplasmic droplets greater than one third the area of a normal sperm head are considered abnormal. They are usually located in the neck/midpiece region of the tail, although some immature spermatozoa may have a cytoplasmic droplet at other locations along the tail.40,42 Under scanning electron microscopy the tail can be subdivided intro three distinct parts (i.e., midpiece, principal piece, and endpiece. In the midpiece the mitochondrial spirals can be clearly visualized. This ends abruptly at the beginning of the midpiece. The midpiece narrows toward the posterior end. A longitudinal column along with transverse ribs is visible. The short endpiece has a small diameter due to the absence of the outer fibers.38 Under transmission electron microscopy, the midpiece possesses a cytoplasmic portion and a lipid-rich mitochondrial sheath that consists of several spiral mitochondria, surrounding the axial filament in a helical fashion. The midpiece provides the sperm with the energy necessary for motility. An additional outer ring of nine coarser fibrils surrounds the central core of 11 fibrils. Individual mitochondria are wrapped around these fibrils in a spiral manner to form the mitochondrial sheath, which contains the enzymes needed in the oxidative metabolism of the sperm. The mitochondrial sheath of the midpiece is relatively short, slightly longer than the combined length of the head and neck.38 The principal piece, the longest part of the tail, provides most of the propellant machinery. The coarse nine fibrils of the outer ring diminish in thickness and finally disappear, leaving only the inner fibrils in the axial core for most of the length of the principal piece.44 The fibrils of the principal piece are surrounded by a fibrous tail sheath, which consist of branching and anastomosing semicircular strands or ribs, held together by their attachment to two bands that run lengthwise along opposite sides of the tail.38 The tail terminates in the endpiece with a length of 4 to 10 μm and diameter of less than 1 μM. The small diameter is due to the absence of the outer fibrous sheath and a distal fading of the microtubules.
REGULATION OF SPERMATOGENESIS The spermatogenic process is maintained by different intrinsic and extrinsic influences.
Intrinsic Regulation Leydig cells secrete hormone (testosterone), neurotransmitters (neuroendocrine substances), and growth factors to neighboring Leydig cells, blood vessels, lamina propria of the seminiferous tubules, and Sertoli cells.5,36,45 They help maintain the nutrition of the Sertoli cells and the cells of the peritubular tissue and influence the contractility of myofibroblasts, thereby regulating the peristaltic movements of the seminiferous tubules and transportation of the spermatozoa. Leydig cells also help in the regulation of blood flow in the intertubular microvasculature.1 In addition, different growth factors are delivered from Sertoli cells and various germ cells participating in a complicated regulation of cell functions and developmental processes of
germ cells. Altogether these factors represent an independent intratesticular regulation of spermatogenesis.
Extrinsic influences The local regulation of spermatogenesis is controlled by the hypothalamus and hypophysis. Pulsatile secretion of gonadotropin-releasing hormone of the hypothalamus initiates the release of LH from the hypophysis; in response the Leydig cells produce testosterone. Testosterone not only influences spermatogenesis, but is also distributed throughout the body. It thus provides feedback to the hypophysis that regulates the secretory activity of Leydig cells. Stimulation of Sertoli cells by FSH is necessary for maturation of the germ cells. Complete qualitative spermatogenesis requires both FSH and LH. The interaction between the endocrine and paracrine mechanisms determines the functions within the testis.46–48 Inhibin secreted by Sertoli cells functions in the feedback mechanism directed to the hypophysis. These extratesticular influences are necessary for the regulation of intratesticular functions. Thus growth and differentiation of testicular germ cells involve a series of complex interactions between both somatic and germinal elements.47,49,50
IMMUNE STATUS OF THE TESTIS The spermatozoa, late pachytene spermatocytes, and spermatids express unique antigens. These antigens are not formed until puberty; therefore, immune tolerance is not developed. The blood–testis barrier develops as these autoantigens develop. The testis is considered to be an immune-privileged site (i.e., transplanted foreign tissue can survive for a period of time without immunologic rejection). An immune surveillance is present in the testis and the epididymis, which shows an active immunoregulation to prevent autoimmune disease.51,52
DISTURBANCES OF SPERMATOGENESIS Both proliferation and differentiation of the male germ cells and the intratesticular and extratesticular mechanisms regulating spermatogenesis can be disturbed. These disturbances may occur as a result of environmental influences or due to diseases that directly or indirectly affect spermatogenesis.53,54 Additionally, nutrition, therapeutic drugs, hormones and their metabolites, increased scrotal temperature, toxic substances, or x-radiation may reduce or destroy spermatogenesis. All these events can result in reduced spermatogenesis.
SPERM TRANSPORT IN THE EPIDIDYMIS The epididymis lies along the dorsolateral border of each testis. It is made up of the efferent ductules, which emanate from the rete testis, and the epididymal ducts (see Fig. 4-1). The epididymis opens into the vas deferens, which then passes through the inguinal canal into the peritoneal cavity and opens into the urethra adjacent to the prostate. The primary function of the epididymis is post-testicular maturation and storage of spermatozoa during their passage from the testis to the vas deferens. The epididymal epithelium is androgen-dependent and has both absorptive and secretory functions.
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Section 1 Basic Science The epididymis is divided into three functionally distinct regions: head, body, and tail or caput epididymis, corpus epididymis, and cauda epididymis. Their functions can be described simplistically as increasing the concentration, maturation, and storage of the spermatozoa. Much of the testicular fluid that transports spermatozoa from the seminiferous tubules is resorbed in the caput, increasing the concentration of the spermatozoa by 10-fold to 100-fold. The epididymal epithelium secretes the epididymal plasma in which the spermatozoa are suspended. As the newly developed spermatozoa pass through these regions of the epididymis, many changes occur, including alterations in net surface charge, membrane protein composition, immunoreactivity, phospholipid and fatty acid content, and adenylate cyclase activity. Many of these changes are thought to improve the structural integrity of the sperm membrane and also increase the fertilization ability of the spermatozoa. The capacities for protein secretion and storage within the epididymis are known to be extremely sensitive to temperature and reproductive hormone levels, including estrogens. It is a complex fluid whose composition changes along the length of the epididymis; and spermatozoa experience a series of sophisticated microenvironments that regulate their maturation.
Epididymal Sperm Storage As many as half of the spermatozoa released from the testis die and disintegrate within the epididymis and are resorbed by the epididymal epithelium. The remaining mature spermatozoa are stored in the cauda epididymis, which contains about 70% of all spermatozoa present in the male tract. The cauda epididymis stores sperm available for ejaculation. The ability to store functional sperm provides a capacity for repetitive fertile ejaculations. The capacity for sperm storage decreases distally; spermatozoa in the vas deferens may only be motile for a few days. The environment of the cauda epididymis is adapted for storage in laboratory animals. In humans it is not a perfect storage organ, and the spermatozoa do not remain in a viable state indefinitely. After prolonged sexual activity, caudal spermatozoa first lose their fertilizing ability, followed by their motility and then their vitality; they finally disintegrate. Unless these older, senescent spermatozoa are eliminated from the male tract at regular intervals, their relative contribution to the next ejaculate(s) increases, thereby reducing semen quality, even though such ejaculates do have a high sperm concentration. The vas deferens are not a physiologic site of sperm storage and contain only about 2% of the total spermatozoa in the male tract. The transit time of sperm through the fine tubules of the epididymis is thought to be 10 to 15 days in humans.
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Early on, the nucleus of the round spermatid is spherical and is located in the center of the cell. Subsequently, the shape changes from spherical to asymmetric as chromatin condenses. It is theorized that many cellular elements contribute to the reshaping process, including chromosome structure, associated chromosomal proteins, the perinuclear cytoskeletal theca layer, the manchette of microtubules in the nucleus, subacrosomal actin, and Sertoli cell interactions. As spermatozoa traverse the epididymis, they are exposed to a continuously changing milieu of the luminal fluid derived from
the rete testis and modified by the secretory and absorptive activity of the epididymal epithelium. In nonhuman mammals there is compelling evidence that the epididymal epithelium does provide essential factors for sperm maturation.55–58 In humans most of the information is obtained from treatment of pathologic cases rather than from normal fertile men. Sperm maturation occurs outside the testis. Spermatozoa within the testis have very poor or no motility and are incapable of fertilizing an egg. Both epididymal maturation and capacitation is necessary before fertilization. Capacitation, the final step required to acquire the ability to fertilize, may be an evolutionary consequence of the development of a storage system for inactive sperm in the caudal epididymis. Preservation of optimal sperm function during this period of storage requires adequate testosterone; levels in the circulation. The epididymis is limited to a storage role because spermatozoa that have never passed through the epididymis and that have been obtained from the efferent ductules in men with congenital absence of vas deferens can fertilize the human oocyte in vitro and result in pregnancy with live birth (as well as with intracytoplasmic sperm injection with sperm obtained after testicular biopsy). A direct involvement of the epididymis comes from the results of epididymovasostomy bypass operations for epididymal obstruction. However, these results are not consistent, whereas significantly reduced fertility was reported in anastomosis of vas deferens to the proximal 10 mm of the duct compared to anastomosis of the more distal region of the tract59; others have reported pregnancies in anastomosis of the vas deferens to the efferent ductules60 or from spermatozoa retrieved from the efferent ductules and proximal caput regions of men with congenital absence of vas deferens and used for successful in vitro fertilization.60 More direct evidence of epididymal involvement comes from experiments in which immature epididymal sperm recovered from fertile men were incubated in the presence of human epithelial cell cultures.61 These spermatozoa showed improved motility and a significant increase in their capacity to attach to human zona in vitro.
SPERM ENTRY INTO CERVICAL MUCUS At the moment of ejaculation, spermatozoa from the cauda epididymis are mixed with secretions of the various accessory glands in a specific sequence and deposited around the external cervical os and in the posterior fornix of the vagina. Spermatozoa in the first fraction of the ejaculate have significantly better motility and survival than those in the later fractions. The majority of the spermatozoa penetrate cervical mucus within 15 to 20 minutes of ejaculation.62,63 The ability to migrate across the semen–mucus interphase is highly dependent on the specific movement pattern of the spermatozoa.64 At the time of sperm penetration into the cervical mucus, further selection of the spermatozoa occurs based on the differential motility of normal versus abnormal spermatozoa. This is further modified once the vanguard spermatozoon is within the cervical mucus.65 The receptivity of the cervical mucus to penetration by the spermatozoa is cyclic, increasing over a period of about 4 days before ovulation and decreasing rapidly after ovulation. Maximum receptivity is seen the day before and on the day of the LH peak.66 Spermatozoa enter the uterine cavity from the internal cervical os by virtue of their own motility.67 From here
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Chapter 4 Physiology of Male Gametogenesis the spermatozoa traverse to the site of fertilization in the ampulla of the fallopian tube or the oviduct.
CAPACITATION AND THE ACROSOME REACTION Animal studies in rats and rabbits indicate that spermatozoa that are stored in the female tract are unable to penetrate the ova. They have to spend time in the female tract before they acquire this ability. Capacitation is a series of cellular or physiologic changes that spermatozoa must undergo to fertilize.68,69 It is characterized by the ability to undergo the acrosome reaction, to bind to the zona pellucida, and to acquire hypermotility. Capacitation may be an evolutionary consequence of the development of a storage system for inactive sperm in the caudal epididymis. Capacitation per se does not involve any morphologic changes even at the ultrastructural level. It represents a change in the molecular organization of the intact sperm plasmalemma that then confers on spermatozoa the ability to undergo the acrosome reaction in response to induction of the stimulus. Capacitation involves the removal of seminal plasma factors that coat the surface of the sperm; modification of the surface charge; modification of the sperm membrane and of the sterols, lipids, and glycoproteins and the outer acrosomal membrane lying immediately under it. It also involves an increase in intracellular free calcium.70,71 Changes in sperm metabolism, increase in 3′, 5′-cyclic monophosphate, and activation of acrosomal enzymes are believed to be components of capacitation. Sperm capacitation may be initiated in vivo during migration through cervical mucus.72 This is finally followed by the acquisition of hypermotility, displayed by an increase in velocity and flagellar beat amplitude. This may be necessary for avoiding attachment to the tubal epithelium and penetrating the cumulus and zona pellucida. Capacitation can also be achieved by culture medium supplemented with appropriate substrates for energy and in the presence of protein or biologic fluid such as serum or follicular fluid. Usually it takes about 2 hours for sperm to undergo capacitation in vitro. Further modifications occur when capacitated sperm reach the vicinity of the oocyte. The acrosome reaction confers the ability to penetrate the zona pellucida and also confers the fusogenic state in the plasmalemma overlying the nonreactive equatorial segment, which is needed for interaction with the oolemma. There are distinct fusion points
between the outer acrosomal membrane and the plasma membrane. The fusion begins posteriorly around the anterior border of the equatorial segment, which is always excluded from the reaction. The changes termed as acrosome reaction prepare the sperm to fuse with the egg membrane. The removal of cholesterol from the surface membrane prepares the sperm membrane for the acrosome reaction.73,74 In addition D-mannose-binding lectins are also involved in the binding of human sperm to the zona pellucida.75,76 Thus, these series of changes are necessary to transform the stem cells into fully mature, functional spermatozoa equipped to fertilize the egg.
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The testis is an immune-privileged site. The blood–testis barrier provides a microenvironment for spermatogenesis to occur. The seminiferous tubules are the site of sperm production. The process of differentiation of a spermatogonium into a spermatid is known as spermatogenesis. It involves both mitotic and meiotic proliferation as well as extensive cell remodeling. In humans, the process of spermatogenesis starts at puberty and continues throughout the entire life. Spermatogenesis produces genetic material necessary for the replication of the species. Meiosis assures genetic diversity. Several cycles of spermatogenesis coexist within the germinal epithelium. Along the length of the seminiferous tubule, there are only certain cross-sections where spermatozoa are released. Sperm production is a continuous and not a pulsatile process. Spermatozoa are highly specialized cells that do not grow or divide. The spermatogenic process is maintained by different intrinsic and extrinsic influences. Spermatozoa undergo a series of cellular or physiologic changes such as capacitation and the acrosome reaction before they can fertilize. The epididymis is limited to a storage role because spermatozoa that have never passed through the epididymis can fertilize the human oocyte in vitro. Nutrition, therapeutic drugs, hormones and their metabolites, increased scrotal temperature, toxic substances, or x-radiation may reduce or destroy spermatogenesis.
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12. Schulze C: Morphological characteristics of the spermatogonial stem cells in man. Cell Tissue Res 198:191–199, 1974. 13. Clermont Y, Bustos-Obregon E: Re-examination of spermatogonial renewal in the rat by means of seminiferous tubules mounted “in toto.” Am J Anat 122:237–247, 1968. 14. Huckins C: The spermatogonial stem cell population in adult rats. I. Their morphology, proliferation and maturation. Anat Rec 169:533–557, 1971. 15. Clermont Y: Two classes of spermatogonial stem cells in the monkey (Cercopithecus aethiops). Am J Anat 126:57–71, 1969. 16. van Alphen MM, van de Kant HJ, de Rooij DG: Depletion of the spermatogonia from the seminiferous epithelium of the rhesus monkey after X irradiation. Radiat Res 113:473–486, 1988. 17. Dym M, Fawcett DW: Further observations on the numbers of spermatogonia, spermatocytes, and spermatids connected by intercellular bridges in the mammalian testis. Biol Reprod 4:195–215, 1971. 18. Berezney R, Coffey DS: Nuclear matrix. Isolation and characterization of a framework structure from rat liver nuclei. J Cell Biol 73:616–637, 1977. 19. Paulson JR, Laemmli UK: The structure of histone-depleted metaphase chromosomes. Cell 12:817–828, 1977. 20. Mirkovitch J, Mirault ME, Laemmli UK: Organization of the higherorder chromatin loop: Specific DNA attachment sites on nuclear scaffold. Cell 39:223–232, 1984. 21. Gasse S: Studies on scaffold attachment sites and their relation to genome function. Int Rev Cytol 119:57, 1989. 22. Izaurralde E, Kas E, Laemmli UK: Highly preferential nucleation of histone H1 assembly on scaffold-associated regions. J Mol Biol 210:573–585, 1989. 23. Adachi Y, Kas E, Laemmli UK: Preferential cooperative binding of DNA topoisomerase II to scaffold-associated regions. Embo J 13:3997, 1989. 24. Dickinson LA, Joh T, Kohwi Y, Kohwi-Shigematsu T: A tissue-specific MAR/SAR DNA-binding protein with unusual binding site recognition. Cell 70:631–645, 1992. 25. Giroux CN: Meiosis: Components and process in nuclear differentiation. Dev Genet 13:387–391, 1992. 26. Russell LD, Griswold MD (eds): The Sertoli Cell. Clearwater, Fla., Cache Press, 1993. 27. Breucker H, Schafer E, Holstein AF: Morphogenesis and fate of the residual body in human spermiogenesis. Cell Tissue Res 240:303–309, 1985. 28. Leblond CP, Clermont Y: Spermiogenesis of rat, mouse, hamster and guinea pig as revealed by the periodic acid-fuchsin sulfurous acid technique. Am J Anat 90:167–215, 1952. 29. Leblond CP, Clermont Y: Definition of the stages of the cycle of the seminiferous epithelium in the rat. Ann NY Acad Sci 55:548–573, 1952. 30. Clermont Y, Perey B: The stages of the cycle of the seminiferous epithelium of the rat: Practical definitions in PA-Schiff-hematoxylin and hematoxylin-eosin stained sections. Rev Can Biol 16:451–462, 1957. 31. Perey B, Clermont Y, LeBlonde CP: The wave of seminiferous epithelium in the rat. Am J Anat 108:47–77, 1961. 32. Schulze W, Rehder U: Organization and morphogenesis of the human seminiferous epithelium. Cell Tissue Res 237:395–407, 1984. 33. Heller CH, Clermont Y: Kinetics of the germinal epithelium in man. Recent Prog Horm Res 20:545–575, 1964. 34. Sculze W, Salzbrunn A: Spatial and quantitative aspects of spermatogenetic tissue in primates. In Neischlag E, Habenicht U (eds): Spermatogenesis-Fertilization-Contraception. Berlin, Heidelberg, New York, Springer, 1992, pp 267–283. 35. Rowe PJ, Comhaire F, Hargreave TB, Mellows HJ (eds): WHO Manual for the Standardized Investigation and Diagnosis of the Infertile Couple. Cambridge, Cambridge University Press, 1993. 36. Sharpe RM: Regulation of spermatogenesis. In Knobill E, Neil JD (eds): The Physiology of Reproduction. New York, Raven Press, 1994, pp 1363–1434. 37. De Kretser DM: Ultrastructural features of human spermiogenesis. Z Zellforsch Mikrosk Anat 98:477–505, 1969. 38. Hafez ESE (ed): Human Semen and Fertility. St. Louis, Mosby, 1976. 39. Kruger TF, Menkveld R, Stander FS, et al: Sperm morphologic features as a prognostic factor in in vitro fertilization. Fertil Steril 46:1118–1123, 1986.
40. Menkveld R, Stander FS, Kotze TJ, et al: The evaluation of morphological characteristics of human spermatozoa according to stricter criteria. Hum Reprod 5:586–592, 1990. 41. Katz DF, Overstreet JW, Samuels SJ, et al: Morphometric analysis of spermatozoa in the assessment of human male fertility. J Androl 7:203–210, 1986. 42. World Health Organization: Laboratory Manual for the Examination of Human Semen and Sperm–Cervical Mucus Interaction. 4th ed. New York, Cambridge University Press, 1999. 43. Barros C, Franklin B: Behaviour of the gamete membranes during sperm entry into the mammalian egg. J Cell Biol 37:13, 1968. 44. White IG: Mammalian sperm. In Hafez ESE (ed): Reproduction of Farm Animals. 3rd ed. Philadelphia, Lea & Febiger, 1974. 45. Jegou B: The Sertoli cell. Baillieres Clin Endocrinol Metab 6:273–311, 1992. 46. de Kretser DM, Sun Y, Drummond AE, et al, (eds): Serono Symposia. USA, pp 19–30. 47. Bellve AR, Zheng W: Growth factors as autocrine and paracrine modulators of male gonadal functions. J Reprod Fertil 85:771–793, 1989. 48. Skinner MK: Cell–cell interactions in the testis. Endocr Rev 12:45–77, 1991. 49. Sharpe T: Intratesticular control of steroidogenesis. Clin Endocrinol 33:787–807, 1990. 50. Sharpe RM: Monitoring of spermatogenesis in man—measurement of Sertoli cell- or germ cell-secreted proteins in semen or blood. Int J Androl 15:201–210, 1992. 51. Mahi-Brown CA, Yule TD, Tung KS: Evidence for active immunological regulation in prevention of testicular autoimmune disease independent of the blood–testis barrier. Am J Reprod Immunol Microbiol 16:165–170, 1988. 52. Barratt CL, Bolton AE, Cooke ID: Functional significance of white blood cells in the male and female reproductive tract. Hum Reprod 5:639–648, 1990. 53. Holstein AF, Schulze W, Breucker H: Histopathology of human testicular and epididymal tissue. In Hargreave TB (ed): Male Infertility. London, Berlin, Heidelberg, New York, Springer, 1994, pp 105–148. 54. Nieschlag E, Behre H (eds): Andrology: Male Reproductive Health and Dysfunction. Berlin, Heidelberg, New York, Springer, 2001. 55. Bedford JM: Effect of duct ligation on the fertilizing capacity of spermatozoa in the epididymis. J Exp Zool 166:271–281, 1967. 56. Orgebin-Crist M: Maturation of spermatozoa in the rabbit epididymis: Fertilizing ability and embryonic mortality in does inseminated with epididymal spermatozoa. Ann Biol Anim Biochem Biophy 7:373–379, 1967. 57. Moore HD, Hartman TD: In vitro development of the fertilizing ability of hamster epididymal spermatozoa after co-culture with epithelium from the proximal cauda epididymis. J Reprod Fertil 78:347–352, 1986. 58. Temple-Smith PD, Southwich GJ, Herrera Casteneda E, et al: Surgical manipulation of the epididymis: An experimental approach to sperm maturation. In Serio M (ed): Perspectives in Andrology. New York, Raven Press, 1989, p 281. 59. Schoysman RJ, Bedford JM: The role of the human epididymis in sperm maturation and sperm storage as reflected in the consequences of epididymovasostomy. Fertil Steril 46:293–299, 1986. 60. Silber SJ, Balmaceda J, Borrero C, et al: Pregnancy with sperm aspiration from the proximal head of the epididymis: A new treatment for congenital absence of the vas deferens. Fertil Steril 50:525–528, 1988. 61. Moore HD, Curry MR, Penfold LM, Pryor JP: The culture of human epididymal epithelium and in vitro maturation of epididymal spermatozoa. Fertil Steril 58:776–783, 1992. 62. Tredway DR, Settlage DS, Nakamura RM, et al: Significance of timing for the postcoital evaluation of cervical mucus. Am J Obstet Gynecol 121:387–393, 1975. 63. Tredway DR, Buchanan GC, Drake TS: Comparison of the fractional postcoital test and semen analysis. Am J Obstet Gynecol 130:647–652, 1978. 64. Mortimer D: Objective analysis of sperm motility and kinematics. In Keel BA, Webster BW (ed): Handbook of Laboratory Diagnosis and Treatment of Infertility. Boca Raton, CRC Press, 1990, pp 97–133.
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Chapter 4 Physiology of Male Gametogenesis 65. Katz DF, Drobnis E, Overstreet JW: Factors regulating mammalian sperm migration through the female reproductive tract and oocyte vestments. Gamet Res 22:443–469, 1989. 66. Mortimer D: Sperm transport in the human female reproductive tract. In Finn CA (ed): Oxford Reviews of Reproductive Biology. Oxford, Oxford University Press, 1983, pp 30–61. 67. Settlage DSF, Motoshima M, Tredway DR: Sperm transport from the external cervical os to the fallopian tubes in women: A time and quantitation study. In Hafez ESE, Thibault CG (ed): Sperm Transport, Survival and Fertilizing Ability in Vertebrates. Paris, INSERM, 1974, pp 201–217. 68. Eddy EM, O’Brien DA: The spermatozoon. In Knobill EO, O’Neill JD (eds): The Physiology of Reproduction. 2nd ed. New York, Raven Press 1988, 135–185. 69. Yanagamachi R: Mammalian fertilization. In Knobill E, O’Brien NJ (eds): The Physiology of Reproduction. New York, Raven Press, 1994. 70. Thomas P, Meizel S: Phosphatidylinositol 4,5-bisphosphate hydrolysis in human sperm stimulated with follicular fluid or progesterone is dependent upon Ca2+ influx. Biochem J 264:539–546, 1989.
71. Mahanes MS, Ochs DL, Eng LA: Cell calcium of ejaculated rabbit spermatozoa before and following in vitro capacitation. Biochem Biophys Res Commun 134:664–670, 1986. 72. Overstreet JW, Katz DF, Yudin AI: Cervical mucus and sperm transport in reproduction. Semin Perinatol 15:149–155, 1991. 73. Parks JE, Ehrenwalt E: Cholesterol efflux from mammalian sperm and its potential role in capacitation. In Bavister BD, Cummins J, Raldon E (eds): Fertilization in Mammals. Norwell, Mass., Serono Symposia, 1990. 74. Ravnik SE, Zarutskie PW, Muller CH: Purification and characterization of a human follicular fluid lipid transfer protein that stimulates human sperm capacitation. Biol Reprod 47:1126–1133, 1992. 75. Benoff S, Cooper GW, Hurley I, et al: Antisperm antibody binding to human sperm inhibits capacitation induced changes in the levels of plasma membrane sterols. Am J Reprod Immunol 30:113–130, 1993. 76. Benoff S, Hurley I, Cooper GW, et al: Fertilization potential in vitro is correlated with head-specific mannose-ligand receptor expression, acrosome status and membrane cholesterol content. Hum Reprod 8:2155–2166, 1993.
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5
Reproductive Genetics Brian A. Clark
INTRODUCTION We learn quickly in life that variability exists between individuals. For many of us the differences are as simple as hair or eye color. For others, the differences are profound and can take the form of a severe birth defect or syndrome. As a whole, these differences add up and cause significant morbidity and mortality. A Canadian study has found that approximately 12% of individuals suffer health problems related to or caused by genetic disease from birth to early adulthood.1 Genetics is the study of traits and inherited differences between individuals; as Gregor Mendel demonstrated, we were able to learn the principles of inheritance without knowing about or understanding DNA and its organization in the genome. The traditional study of medicine and medical genetics is, however, about to be revolutionized. In this technological revolution of genomic medicine, we see that a fundamental understanding of genetics and the principles of inheritance are still required. The practice of clinical medical genetics has been significantly transformed over the past 15 years, from a somewhat arcane specialty dealing with prenatal diagnosis, chromosome abnormalities, and dysmorphology to a challenging and cutting edge specialty taking the lead in introducing genomic medicine to the broader field of medicine. In 2001, the Human Genome Project announced that a rough sequence of the human genome had been completed.2,3 In its original iteration the Human Genome Project was an attempt to sequence and determine the linear sequence of 3 billion base pairs and map the individual genes encoded by this sequence. Genomics is the study of our complete set of genes, their functions and interactions with themselves and their environment, and how genetic variation contributes to disease risk and response to treatment (i.e., pharmacogenomics). This sequencing and mapping effort has now spawned functional genomics, which seeks to identify gene function, regulation, and gene interaction. The knowledge and technologies learned from this effort have, and will have, as profound an impact on the field of reproductive medicine as any other. The physician in obstetrics and gynecology will not only have to have an understanding of genetics and the principles of inheritance, but he or she will also have to understand genomics and its derivative technologies and how these will affect the risk, diagnosis, and treatment of medical disorders. Physicians will not only be practicing the traditional paradigm of diagnosis and treatment of disease, but will also be recognizing and treating genomically derived disease risk prior to disease manifestation. They must be ready to deal with all the ethical, legal, and social implications of this revolution. Although the era of genomic medicine will bring new tools to individualize
disease risk, emphasize prevention, and treat disease, the simple basic recording and understanding of the family history will still be a fundamental component of this new era.4
THE HUMAN GENOME The Human Genome Project has resulted in some surprising revelations.2,3,5 Less than 2% of the human genome has genes that code for proteins. This was a surprising finding because it was thought that the human genome would reflect the complexity of human development and it was estimated that the human genome would contain up to 120,000 genes. The first report of the Human Genome Project estimated that the human genome contained only 30,000 to 35,000 genes. Drosophila melanogaster had been found to have 14,000 genes and the mustard plant Arabidopsis thaliana 26,000 genes.6,7 It is likely now that the complexity of human growth and development and its relation to disease is not going to be explained by just new gene discovery. The previous dogma that one gene produces one protein has now been replaced by the theory of alternative splicing, in which a gene’s exons or coding regions are shuffled to produce alternative forms of a related protein (Fig. 5-1). Exons are sequences of a gene that are transcribed into a protein. Introns are regions of a gene that do not code for a
Exon Gene
1
2
3
4
5
6
1
2
3
4
5
6
RNA Alternative splicing
1
2
3 4 5 6
1
2
3 4 5 6
1
2
3 4 5 6
RNA Translation Protein A
B
C
Figure 5-1 Alternative splicing. A single gene with multiple exons can produce multiple proteins (isoforms) through the mechanism of alternative splicing. A, All 6 exons are translated in the protein. B, The last exon is not translated, producing a truncated protein. C, Exons 4 and 5 are not translated, altering the basic structure of the protein.
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Section 1 Basic Science protein. When the mRNA of a gene is translated, exons are spliced together. Exons have been found to comprise only 1% of the human genome and introns about 25%. Typically more than 25 times the amount of DNA in a gene is not associated with protein structure and function. This has significant implications for DNA testing and interpretation of a test’s sensitivity and specificity. Regions of genes on chromosomes have been described as existing in gene-rich oases separated by gene-sparse deserts. Over 10% of the genome is composed of repeated sequences of DNA that may be related to chromosome structure. Long interspersed repetitive elements and short interspersed repetitive elements have been described, including Alu repeat sequences. Alu sequences have been found in gene-rich regions and may play a role in genetic recombination.
Genetic Variation The human genome contains just over 3 billion base pairs and the sequence is about 99.9% identical in all individuals. It is a surprising finding that human genetic variability may be due to just 0.1% difference in the human genome sequence. A singlenucleotide polymorphism, or SNP, is the most common DNA variant in the genome, with about 10 million occurrences. SNPs are single-base substitutions and occur on average in 1 in every 1250 nucleotides. SNPs are polymorphisms in that a base substitution does not cause a change in the phenotype; they are found in more than 1% of the population. Because of their ubiquity in the human genome SNPs have become invaluable in identifying sequence changes associated with disease risk through traditional linkage studies and population-based association studies. Although not thought to alter protein coding, SNPs have been associated with diseases by their presence in regulatory control regions or introns. SNPs may also determine a disease’s response to treatment, as with the angiotensin-II type 1 receptor polymorphism and its association with congestive heart failure.8
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With the recent advances of the Human Genome Project and the rapid adoption of these findings into clinical medicine, the clinician will need to understand the organization of the human genome. The average size of a gene is about 3000 base pairs. Chromosome 1, the largest chromosome in a karyotype, has about 2968 genes; the Y chromosome, the smallest, has 231 genes. Genes are distributed in random areas of the chromosome, with some chromosomes gene-rich and some gene-poor. Chromosomes 17, 19, and 22 are gene-dense. Chromosomes 4, 8, 13, 18, and Y are gene-sparse. It is not surprising then that chromosomes 13, 18, and 21, which are the common trisomies that can survive to birth, have the fewest genes. Genes can be altered and cause human disease through several mechanisms. Point mutations, in which there is a single change of a DNA base in the sequence, can have multiple effects on gene function. Missense mutation is the substitution of a single base in the DNA sequence, incorporating a different amino acid in the protein sequence. These mutations may have little effect on protein function if the amino acid substituted is similar to the original one. If the substitution incorporates a very different amino acid, the protein structure and function may be significantly affected. A
silent mutation is the substitution of a single base in the DNA sequence that does not change the specific amino acid in the sequence. Nonsense mutations are the substitution of a single DNA base in the sequence, causing the premature termination or truncation of a protein. In addition to point mutations, frame-shift mutations can also lead to an altered or truncated protein. Frameshift mutations are deletions or additions of DNA bases that are not multiples of three. These changes lead to a downstream change in the reading frame, often truncating a protein. In general, these types of mutations result in loss of function of a protein and alter the phenotype by decreasing the activity of a protein.
CHROMOSOMAL BASIS OF INHERITANCE Since Gregor Mendel’s work with the garden pea elucidating the mechanisms of inheritance, genetics has focused on single-gene defects. Modes of inheritance have now been identified for thousands of conditions and catalogued in the online compendium Online Mendelian Inheritance in Man, OMIM at http://www. ncbi.nlm.gov/omim/. Typically an obstetrician-gynecologist will confront chromosome abnormalities under two specific clinical scenarios. The first is in pregnancy where there is an association between chromosome abnormalities and advanced maternal age. There is also an association between miscarriage and chromosome abnormalities; approximately half or more of all first-trimester losses are associated with a chromosome abnormality. Obstetricians and gynecologists will also manage patients with chromosome abnormalities when they present for recurrent pregnancy loss and a history of infertility.
Normal Karyotype Our cells contain 23 pairs of chromosomes; 22 pairs are autosomes and shared between males and females, and one pair is the sex chromosomes, XX and XY. The ordered arrangement of chromosomes is a karyotype. Routine chromosome analysis involves drawing blood and stimulating lymphocytes in culture into rapid division. Cell division is then inhibited at metaphase and the chromosomes fixed on glass slides. The chromosomes are then stained and photographed for analysis.
CHROMOSOME ABNORMALITIES Chromosome abnormalities fall into two general categories: numerical and structural. In numerical abnormalities the total number varies from the normal, 46. With structural abnormalities, the chromosome structure has been physically rearranged.
Chromosome Structure Chromosomes are composed of short arms, p, and long arms, q. The chromosome has a primary constriction, or centromere, where the microtubules attach for cell division. The telomeres, or tips of the chromosomes, are capped with a repeating sequence TTAGGG that is critical for the maintenance of chromosome integrity. The relative position of the centromere further delineates the structure of the chromosome. In humans the acrocentric chromosomes 13, 14, 15, 21, and 22 are characterized by stalks and satellites where genes for ribosomal RNA are located (Fig. 5-2).
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Chapter 5 Reproductive Genetics Numerical Abnormalities Abnormalities of chromosome number are the most commonly recognized clinical chromosome abnormalities. Structural chromosome anomalies contribute significantly to birth defects, infertility, and recurrent pregnancy loss. Abnormalities in chromosome number generally arise from mistakes at cell division where there is either gain or loss, or both, of chromosomes in daughter
Short arm p 13 12 11
Centromere
Satellite
Stalk
12 21 22
Long arm q
3 Metacentric
Telomere
Structural Chromosome Abnormalities
25 17 Submetacentric
21 Acrocentric
Figure 5-2 Human chromosomes. These chromosomes represent the pattern seen with G banding or Giemsa staining. The different types of chromosomes and elements of chromosome structure are noted. The bands for chromosome 17 are numbered.
Meiosis I
Meiosis II
Structural chromosomal rearrangements occur when chromosomes break and the original architecture is not restored. Chromosome rearrangements are balanced when the diploid genetic state is maintained. When rearrangements are unbalanced, they result in aneuploidy for one or more chromosome segments. These structural rearrangements may segregate and be
Mitosis
Meiosis I
Replication of genetic material
Meiosis II
Mitosis
A
cells, or nondisjunction. Nondisjunction can occur either during meiosis or mitosis. Cells resulting from this occurrence are aneuploid because their chromosome number is not a multiple of the haploid number 23. Nondisjunction can occur during either meiosis I or meiosis II. Either can produce an aneuploid conception (Fig. 5-3). Nondisjunction or anaphase lag can occur at mitosis, causing mosaicism, the presence of two or more cell lines in an individual. Mosaicism is often seen with the sex chromosome abnormality Turner’s syndrome, where up to 50% of cases have some form of mosaicism.9 The common numerical chromosome abnormalities are listed in Table 5-1. Numerical chromosome abnormalities can also involve multiples of the haploid number of 23 chromosomes. Triploidy, with 69 chromosomes, usually arises from the fertilization of a single egg by two sperm. Triploid conceptions are seen in about 15% of chromosomally abnormal miscarriages and occasionally survive to term. Tetraploidy has a modal number of 92 chromosomes and occurs in a small percentage of spontaneous losses.
C
B Figure 5-3 Nondisjunction. A, Nondisjunction can occur at meiosis I, producing an aneuploid gamete and trisomic conception. The polar bodies are represented by empty circles. B, Postzygotic or mitotic nondisjunction can occur, producing somatic mosaicism. This is seen frequently in Turner’s syndrome. C, Nondisjunction in meiosis II can produce normal gametes, along with those with 22 and 24 chromosomes.
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Section 1 Basic Science Table 5-1 Chromosome Abnormalities
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Chromosome
Clinical Findings
Trisomy 13
Severe CNS abnormalities, holoprosencephaly, microphthalmia, coloboma, cleft lip and palate, abnormal auricles, polydactyly, cardiac defects
Trisomy 18
CNS malformations, prominent occiput, micrognathia, small mouth, low-set ears, hypoplastic nails, overlapping fingers, cardiac defects
Trisomy 21
Microcephaly, flat occiput, Brushfield spots, epicanthal folds, simian crease, conotruncal cardiac defects, redundant skin on nape of neck, hypotonia
XXX
Normal female phenotype, tall stature, may have some learning and developmental disabilities, normal fertility
45,X Turner’s
Short stature, gonadal failure, absent secondary sex characteristics, webbed neck, low-set hairline, coarctation of the aorta, horseshoe kidney, may have some spatial learning disabilities
XXY Klinefelter’s
May be tall, infertile, small testis, learning disabilities, gynecomastia
termed familial, or they may occur as a first or new event, de novo. Balanced familial chromosome rearrangements are in most cases truly balanced and represent little risk of birth defects or mental retardation. De novo chromosome rearrangements that appear balanced carry a small risk of aneuploidy at the molecular level of about 5% for birth defects and developmental delay. Translocations involve the exchange of chromosome arms between two different chromosomes. Reciprocal translocations occur when there is breakage within two arms and reciprocal exchange of the distal segments, creating a derivative chromosome (Fig. 5-4). In most cases balanced translocation carriers are phenotypically normal but are at risk for producing unbalanced gametes during gametogenesis. In a balanced translocation carrier the types of chromosome segregation can be complex, resulting in a normal segregation pattern, a balanced translocation pattern, and an unbalanced pattern producing a partial trisomy and partial monosomy for the chromosomes involved (see Fig. 5-4). When the short arms of two acrocentric chromosomes are involved in a translocation, the long arms are joined in the centromeric region of one chromosome, with the loss of the short arms of the acrocentric chromosomes producing Robertsonian translocations. Because the short arms of acrocentric chromosomes contain redundant ribosomal genetic material, the loss of this material is of no phenotypic consequence. As with balanced translocations, the products of meiotic segregation can be either balanced or unbalanced (Fig. 5-5). Other structural abnormalities can produce pregnancy loss and birth defects. When two breaks occur in a single chromosome with the interstitial segment flipped 180 degrees at the time of repair, an inversion can occur. If this involves each arm of the chromosome a pericentric inversion is produced. If only a single arm of the chromosome is involved in the inversion, a paracentric inversion is produced (Fig. 5-6). Each has unique and different implications for gamete production and pregnancy loss. With chromosome duplication a chromosome segment of varying size can be duplicated, causing a partial trisomy for this segment. With a deletion, a segment of varying size is missing, causing a genetic imbalance or partial monosomy. This condition, in which a second copy of a gene or segment of chromosome is missing,
A
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Balanced
Adjacent -1
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Unbalanced
Figure 5-4 Reciprocal translocation between two nonhomologous chromosomes. A, Germ line chromosomes of a balanced translocation carrier. B, Alternate segregation produces gametes with normal chromosomes and balanced translocation products. C, Adjacent-1 segregation produces unbalanced gametes, resulting in partial monosomy and partial trisomy conceptions.
resulting in an abnormal phenotype or clinical presentation, is known as haploinsufficiency.
Fluorescent In Situ Hybridization Traditional cytogenetics has always been limited by the band level or resolution of the karyotype. Even with high-resolution banding that could elongate chromosomes and resolve an increasing number of bands per chromosome, one could never be certain that a chromosome was intact at the molecular level. With advances in DNA technology and cytogenetics it is now possible using fluorescent in situ hybridization (FISH) to analyze chromosomes at the molecular level for changes in the DNA. Molecular cytogenetics has now revolutionized cytogenetics by permitting (1) the analysis of DNA structure within a chromosome down to within 10 to 100 kb and (2) the diagnostic analysis of nondividing interphase cells, producing a significant impact on the field of prenatal diagnosis and that of preimplantation genetic diagnosis.10 FISH technology uses DNA probes that can bind or anneal to specific DNA sequences within the chromosome. A denatured probe is incubated with native DNA from a cell that has also been denatured to the single-strand state. The probe substitutes biotin-dUTP or digoxigenin-UTP for thymidine. After the probe has annealed to native DNA, the probe–DNA complex can be detected by adding fluorochrome-tagged avidin that binds to
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Balanced
biotin or fluorochrome-labeled antidigoxigenin. This signal can be additionally amplified by adding antiavidin and the complex visualized by fluorescence microscopy. Using several different fluorochromes tagged to different DNA probes, different chromosomes or chromosome segments can be simultaneously visualized within a cell as different colored signals. The ability to detect specific gene segments that are either present or missing has permitted the diagnosis of contiguous gene syndromes at the DNA level as well as translocations in interphase nuclei, often in single cells. Material for FISH can be either metaphase chromosomes obtained from dividing cells or interphase nuclei from cells that are not dividing. Slides are pretreated with RNAse and proteinase to remove RNA that may cross-hybridize with the probe and chromatin. The slides are heated in formamide to denature the DNA and then fixed in cold ethanol. The probe is then prepared for hybridization by heating. The probe and chromosome preparation are then mixed and sealed with a coverslip at 37° C for hybridization. By varying the incubation temperature or the salt composition of the hybridization solution, the stringency of the binding can be increased and the background labeling reduced.
Applications of FISH Unbalanced
Translocation Down syndrome
Monosomy 21 nonviable
Figure 5-5 Robertsonian translocation. A translocation has occurred between two acrocentric chromosomes. A, Normal and balanced segregants will produce genetically-balanced offspring. B, The unbalanced segregants will produce translocation Down syndrome and the nonviable monosomy 21.
The technique of in situ hybridization first proved useful for localizing genes to chromosomes. With the introduction of fluorescence labeling, in situ hybridization proved invaluable in identifying chromosome abnormalities that could not be identified by traditional banding methods. FISH also played a key role in one of the most unusual discoveries of modern genetics, that of genomic imprinting. FISH technology has been developed in three forms. Centromeric or alpha-satellite probes are relatively chromosome specific and have had probably the broadest application in interphase genetics.11,12 These probes produce somewhat diffuse signals near the centromere with adequate strength, but do not cross-hybridize with chromosomes that have similar centromeric sequences. Single copy probes have now been developed that give discrete signals from a specific band on a chromosome and avoid the issue of cross-hybridization. These can also be used to detect copy number and specific chromosome regions known to be associated with syndromes. Single copy probes and centromeric probes for chromosomes 13, 18, 21, X, and Y have been developed for use in prenatal diagnosis. It is also possible to “paint” whole chromosomes using FISH. Using spectral karyotyping technology that combines mixtures of fluorochromes, it is now possible to produce a unique fluorescent pattern for each individual chromosome in 24 different colors. This technology permits the detection of complex chromosome rearrangements that cannot be seen with traditional cytogenetic techniques (Fig. 5-7).
Prenatal Diagnosis Normal homolog
Pericentric inversion
Normal homolog
Paracentric inversion
Figure 5-6 The inversion on the left is a pericentric inversion involving the centromere. The inversion on the right is a paracentric inversion involving a single chromosome arm.
For an older woman, pregnancy may not be a time of joy but a time of anxiety. Advanced maternal age has a long-known association with an increasing risk of fetal chromosome abnormalities. Amniocentesis done at 16 weeks’ gestation followed by traditional karyotype analysis may take from 10 days to 2 weeks. The use of FISH for preliminary results can expedite a diagnosis
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Section 1 Basic Science Table 5-2 Deletion and Contiguous Gene Syndromes
Figure 5-7 Patterns of FISH probes in interphase cell preparations. The first figure shows a hypothetical locus-specific probe with a discrete signal. The middle figure shows a centromeric repeat probe with a larger, more diffuse signal. The figure on the right shows a whole chromosome painting probe with the diffuse pattern of overlapping domains making chromosome enumeration less reliable.
Deletion
Syndrome
Clinical Description
4p–
Wolf-Hirschhorn
Microcephaly, hypertelorism, frontal bossing, cleft lip and palate, “Greek helmet” face, mental retardation, hypotonia, cardiac anomalies
5p–
Cri du chat
Microcephaly, characteristic “cat cry,” hypotonia, mental retardation
7q11.23
Williams
Round face, full lips, stellate iris, supravalvular aortic stenosis, mental delay, “cocktail personality”
11p13
WAGR
Wilm’s tumor, aniridia, genital abnormalities, mental retardation
15q11-13
Angelman
Blonde hair, prognathism, seizures, ataxia, laughter, hypotonia, mental retardation
15q11-13
Prader-Willi
Birth hypotonia, hyperphagia, obesity, short stature, hypogonadism, mental retardation
16p13
Rubinstein-Taybi
Characteristic facies, beaked nose, microcephaly, mental retardation
17p11
Smith-Magenis
Brachycephaly, prominent chin, short stature, mental retardation, behavioral phenotype
17p13
Miller-Dieker
Microcephaly, lissencephaly, growth retardation, seizures, mental retardation
20p12
Alagille
Cholestasis, heart defects, ocular findings, skeletal defects
22q11
DiGeorge/CATCH 22
Thymic and parathyroid hypoplasia, calcium abnormalities, conotruncal heart defects, short stature, behavioral and learning problems
compendium of deletion syndromes has reported 18 deletion and microdeletion syndromes spread over 14 chromosomes.13 Some of the more common deletion and mirodeletion syndromes and their clinical findings are shown in Table 5-2. Figure 5-8 DiGeorge probe. This photo shows a peripheral blood sample from a patient tested for DiGeorge syndrome. The Tuple 1 probe binds to both copies of chromosome 22 as does the control. The child did not have the deletion causing DiGeorge syndrome.
and reduce the waiting time for results. Most geneticists and laboratories recommend that FISH not be used alone to make a management decision in pregnancy. FISH studies should always be confirmed with a final karyotype or at minimum correlated with abnormal ultrasound findings or an abnormal maternal serum analyte screen.
Contiguous Gene Syndromes
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Contiguous gene syndromes are also known as microdeletion syndromes, or segmental aneusomy.10 These are deletions of a contiguous stretch of chromosome that usually involve multiple genes. The contiguous gene syndromes were first described in 1986 using classical cytogenetic methodologies. Using FISH, submicroscopic deletions can now be identified at the level of DNA; this has permitted the characterization of the smallest deleted region consistently associated with a syndrome, known as the critical region. By identifying the critical region of a syndrome, it is often possible to identify the specific genes that, when missing, are associated with the syndrome (Fig. 5-8). A recent
Telomeres Telomeres are structures that cap the tips of the long and short arms of chromosomes. They are composed of repeating sequences of TTAGGG and effectively prevent the ends of the chromosomes from fusing together. Telomere probes can be important in sorting out complex translocations that cannot be determined by traditional cytogenetic means. In addition, one of the findings of the Human Genome Project was that the chromosome regions next to telomeres are gene-rich. It has now been shown that submicroscopic subtelomeric deletions are responsible for a significant proportion of genetic morbidity.14
GENERAL PRINCIPLES OF MENDELIAN GENETICS Single-Gene Disorders In humans as with all diploid organisms, genes come in pairs on related or homologous chromosomes. The exception to this is the sex chromosomes, the X and the Y in the male. Single-gene disorders are described on the basis of the interaction of these pairs or alleles in the genotype and on how the interaction is expressed in the effect or the phenotype. When the alleles are not identical, the genotypes are heterozygous. When the alleles
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Chapter 5 Reproductive Genetics are identical, the genotype is described as homozygous. Gregor Mendel recognized that single-gene disorders are often recognizable and that these single-gene disorders segregate in families with predictable proportions; they have thus been referred to as mendelian traits.15 If a single-gene disorder manifests itself in the heterozygous state, the condition is inherited in a dominant manner. If the single-gene disorder is only inherited when both alleles are affected or altered, the condition is inherited in a recessive fashion. In addition, single-gene disorders are further characterized according to whether they are transmitted on the autosomes or the sex chromosomes.
Autosomal Dominant Inheritance The following features characterize autosomal dominant inheritance: 1. In most cases an affected individual has an affected parent. 2. Males and females are equally likely to be affected. 3. Affected individuals have a 50:50 chance of passing on the condition to an offspring. Unaffected individuals will in general not pass on the condition. 4. Within a family, about half the individuals are affected and half unaffected. 5. Within a pedigree the overall pattern is that of vertical transmission, with the disorder appearing in each successive generation. An example of an autosomal dominant pedigree is seen in Figure 5-9. Autosomal dominant inheritance patterns have additional characteristics that the clinician must recognize. Not all individuals in a family who have inherited a dominant condition are affected to the same extent or have the same organ systems affected. This characteristic is known as variable expressivity. This is one reason why it is important in clinical genetics to examine other family members when a proband, or referred patient, is initially evaluated. An autosomal dominant condition is considered fully penetrant if all individuals who inherit the single-gene mutation manifest its characteristics. Many autosomal dominant conditions have reduced penetrance, and not all individuals with the dominant gene manifest its phenotype. For women who inherit a BRCA1 or BRCA2 gene mutation, the lifetime risk of developing a breast cancer is 85%. Therefore, some families that are segregating BRCA1 and BRCA2 mutations will appear to “skip generations” when in fact an individual will carry a mutation but will not develop a breast cancer in her lifetime. There are in addition other characteristics of autosomal dominant inheritance. Autosomal dominant conditions are rarely found
Figure 5-9 Pedigree: Autosomal dominant inheritance. Filled-in symbol signifies affected individual. Transmission occurs to sons and daughters.
in the homozygous condition and almost always result in embryonic lethality. Finally, autosomal dominant conditions will occur in families with no previous family history. This does not imply nonpaternity, which the clinician must be aware of. For example, new mutations occur in Marfan syndrome in about 25% of cases and about 80% of cases in achondroplasia.16 Parents of such an affected child are unlikely to be at risk for having another affected child; however, for the child, the risk of passing the condition on to an offspring is 50%. Geneticists have all been faced with the clinical scenario where a dominant, sporadic condition occurred in a family with a negative family history. Traditional genetic counseling would consider the recurrence risk negligible. However, most geneticists have seen these conditions recur in families, and empirically the recurrence risk has been as high as 3% to 5%. This phenomenon is usually attributed to germ cell mosaicism caused by a postzygotic nondisjunctional chromosome event or nondisjunctional mutational event. Presumably one of the parents in such a case has a small population of germ cells carrying the mutation. Recurrence risks must therefore be revised upward.
Autosomal Recessive Inheritance Autosomal recessive inheritance has features distinct from autosomal dominant inheritance. Autosomal recessive inheritance is characterized by the following conditions: 1. Parents are usually unaffected, and affected individuals do not have affected parents. 2. Males and females are equally affected. 3. The condition usually occurs in siblings, with a horizontal pattern of inheritance within a generation. 4. Recurrence risks for subsequent pregnancies is 25%. 5. Consanguinity or relatedness is frequently observed in recessively inherited pedigrees. An example of an autosomal recessive pedigree is shown in Figure 5-10. Autosomal recessive inheritance requires an affected individual to be homozygous; therefore, these traits tend to occur less frequently than dominantly inherited disorders. For some conditions, such as cystic fibrosis, in which many of the mutations causing the disorder are known, carrier status can be determined by DNA testing. In other conditions in which the gene
Figure 5-10 Pedigree: Autosomal recessive inheritance. The individuals with central dots indicate obligate carriers. Filled-in symbol signifies affected individual.
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Section 1 Basic Science
Figure 5-12 Pedigree: X-linked dominant inheritance. More females than males are affected. Filled-in symbol signifies affected individual. Figure 5-11 Pedigree: X-linked recessive inheritance. The individuals with central dots indicate obligate carriers. All daughters of affected males are carriers. Male-to-male transmission does not occur. Filled-in symbol signifies affected individual.
product is known, the level of an enzyme, approximately 50% of normal, can determine carrier status.
X-linked Inheritance Because there are relatively few genes on the Y chromosome, sexlinked disorders are primarily X-linked disorders. Because males have only one copy of the X chromosome, they are hemizygous for X-linked genes and are in general affected by any mutation on the X chromosome. Because of this differential expression in males, X-linked disorders (e.g., hemophilia) were the earliest recognized human genetic disorders. Characteristics of X-linked inheritance are: 1. There is no male-to-male transmission of the condition. 2. Males are much more frequently affected than females. That some females can be affected is explained by X inactivation. 3. Affected males have obligate carrier daughters. 4. Mothers of affected males are obligate carriers. Half of their sons will be affected, and half of their daughters are carriers. An example of X-linked recessive inheritance is shown in Figure 5-11. Complete androgen insensitivity (testicular feminization) syndrome is an X-linked recessive disorder that presents as primary amenorrhea. These patients have a 46,XY genotype with a mutation in the androgen receptor gene located on the long arm of the X chromosome (Xq11-12). Mutations of this gene can also cause partial androgen insensitivity with genital androgenization or a milder form with abnormalities of spermatogenesis. These patients have normal-appearing female phenotype but with sparse pubic and axillary hair, short vagina, no müllerian derivatives, and normal testes. The testes can be in the abdomen or inguinal canal. The testes are removed after completion of spontaneous puberty. The serum androgen levels are in the male range. X-linked dominant conditions are less common disorders than X-linked recessive disorders, with vitamin D-resistant rickets an example of this type of inheritance. Characteristics of this type of inheritance are:
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1. Affected males have affected daughters, not sons. 2. The mutation may be lethal in males for some conditions. 3. Affected females tend to be twice as common as affected males in the pedigree. 4. Affected females on average transmit the disorder to half their daughters and sons.
An example of X-linked dominant inheritance is shown in Figure 5-12.
X Chromosome Inactivation Some females might be affected by X-linked recessive disorders through X chromosome inactivation. Only one X-linked gene and one X chromosome are active in the somatic tissues of women. For all autosomal genes there are two copies; in terms of gene dosage and transcriptional activity, there is an equal amount in the somatic cells of men and women. To keep transcriptional activity and gene dosage equal for the X chromosome between men and women, the X chromosome would have to be twice as active in males or one X chromosome could be inactivated in females. Transcriptional equality is maintained by the inactivation of most but not all of the genes on the X chromosome in female somatic tissues. Reversible X inactivation is accomplished by methylation. For a woman who is heterozygous for an X-linked disorder, only one gene is active in each cell; she is functionally a mosaic of cells expressing either the normal or abnormal gene product. If random X chromosome inactivation is skewed in the direction of inactivating the normal gene in most cells, a woman may manifest the signs of an X-linked disorder. This can be seen in women who are carriers for hemophilia who may have the bleeding tendencies of their affected sons. This variability in X chromosome gene expression has another significant clinical effect. Skewed X chromosome inactivation favoring the normal gene product will cause an overlap in the level of the gene product for a carrier woman and a noncarrier woman. This will not only make it difficult to identify a carrier from a noncarrier female, but will also mean that an inherited disorder cannot be distinguished from a new mutation.
NONTRADITIONAL INHERITANCE Mendel laid the foundation of modern genetics in 1865 by describing dominant and recessive inheritance. For some time inherited diseases were considered to result from single-gene mutations that followed his classic principles of inheritance. Now with new genetic technologies and discoveries from the Human Genome Project, we know that not all inherited diseases follow these traditional principles of inheritance. Several new forms of nontraditional inheritance have now been described.
Multifactorial Disorders There are many birth defects, genetic conditions such as congenital heart disease and spina bifida, and adult onset disorders
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Chapter 5 Reproductive Genetics that cannot be explained by single genes or the traditional patterns of inheritance. Yet, many of these conditions are clearly familial. These conditions are considered to be the result of additive genetic and environmental factors that trigger a threshold for expression in development or adulthood. Multifactorial inheritance attributes disease risk to a combination of multiple genetic factors that interact with an environmental stimulus. Polygenic traits are those diseases attributable to the additive effect of several genes. Often, these two concepts are used interchangeably. Evidence for multifactorial or familial inheritance has led to a threshold model of genetic liability. This model assumes a continuous normal distribution of genetic risk in the population in the form of a bell-shaped curve. Affected individuals are considered to fall to the far right of the genetic liability curve. Affected first-degree relatives (siblings, parents, and children) would also fall to the right of the curve, but not as far. As the degree of relatedness falls off, the genetic liability falls back to that of the general population.15 Evidence for multifactorial inheritance can be found in the following: 1. Some disorders are found more commonly in certain racial or ethnic groups, such as neural tube defects in the Irish. 2. Higher frequencies of birth defects are found in the relatives of affected individuals than the population at large. The incidence of birth defects falls off with the degree of relatedness. For example, the incidence of cleft lip with or without cleft palate is 4% in first-degree relatives, 0.8% in second-degree relatives, and 0.3% in third-degree relatives. 3. Single-gene disorders are found to be 100% concordant in monozygotic twins. For multifactorial inheritance in identical twins concordance is expected to be less than 100%, but much higher than in nonidentical twins. Concordance for cleft lip/palate in identical twins is 40%, whereas it drops to 4% in nonidentical twins. Multifactorial inheritance also has specific implications for recurrence risks. Unlike recurrence risks for mendelian disorders, recurrence risks for multifactorial inheritance are empirically derived. General guidelines for multifactorial inheritance are: 1. Recurrence risks are empirically derived and may vary among families. The recurrence risk decreases with decreasing degree of relationship. 2. Within a family the risk increases with the number of affected family members. The risk to a sibling increases with each affected sibling. 3. The risk increases with the severity of the malformation. The more severe the condition, the greater the risk to the sibling. 4. When there is a predilection for the disorder in one sex over the other, there is often a greater risk to the offspring of the least affected sex versus the other. Presumably the lesseraffected sex has a higher genetic liability and a greater number of affected genes, putting a greater risk on their offspring.
Mitochondrial Inheritance Genes located on chromosomes in a cell nucleus exhibit mendelian patterns of inheritance. However, there is an extranuclear source of DNA found in the mitochondria in the cytoplasm of cells. The mitochondria are a major source of adenosine triphosphate (ATP) for the energy requirements of a cell. Through the electron transport chain producing large amounts of NADH, ATP is generated in
Figure 5-13 Pedigree: Mitochondrial inheritance. Both males and females can be affected, but inheritance only occurs from an affected mother.
a process known as oxidative phosphorylation. Mitochondria have their own DNA, mtDNA, in the form of a circular 16,596 base pair chromosome. This chromosome contains the genes for 13 polypeptides of the oxidative phosphorylation system, 22tRNAs, and 2 rRNAs. However, most of the proteins in the mitochondria are encoded by nuclear genes, transcribed in the cytosol, and transferred into the mitochondria via molecular chaperones. Each cell contains thousands of mitochondria and each mitochondrion contain from 2 to 20 mtDNAs. Unlike nuclear genes, mtDNA follows a maternal line of transmission. Each oocyte contains from 200,000 to 300,000 mtDNA molecules. At fertilization the sperm have few mitochondria, located in the tails, and their contribution of mitochondria to the conception is negligible. An example of mitochondrial or maternal inheritance is shown in Figure 5-13. Both males and females can be affected, but inheritance only occurs from an affected mother. The phenotype of a mitochondrial disorder may be quite variable because of the nature of the mutation itself and its distribution within the population of mitochondria. At fertilization the oocyte contains thousands of mitochondria, both mutant and normal. At cell division, the proportion of mutant and normal mitochondria distributed to each daughter cell is never even. In addition, as the embryo grows new mutations accumulate in the mtDNA. Therefore, any cell or organ system may have proportionately few or many mutant mitochondria. This characteristic of mitochondrial inheritance is known as heteroplasmy. Within a single family there may be different manifestations of the same mitochondrial disease and within an individual the manifestations may change over time. As predicted with disorders of the oxidative phosphorylation system, those organ systems affected are those with the highest energy demands. Examples of mitochondrial disorders include Leber hereditary optic neuropathy, myoclonic epilepsy with red ragged fibers, and mitochondrial myopathy, encephalopathy, lactic acidosis, and strokelike episodes.
Imprinting Pronuclear transplantation studies in mice have shown a reversible effect of the sex of the parent on the embryo. Mice can be conceived with both haploid chromosome complements coming from either the father or the mother. Mouse zygotes with paternally derived genes have arrested embryonic development but near-normal placental development. Zygotes with maternally derived genes have embryonic development but arrested placental development. Thus it became apparent that specific genes are differentially marked, or imprinted, at gametogenesis depending on whether they are inherited from the mother or
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Section 1 Basic Science father. This process is known as genomic imprinting. An example of this has long been familiar to the obstetrician/gynecologist. Hydatidiform moles are placental tumors without embryonic tissue with a genome derived from two paternal sets of haploid chromosomes. Ovarian teratomas are embryonic tumors without placental tissue derived from two maternal sets of haploid chromosomes. Triploidy also demonstrates examples of genomic imprinting. Android embryos with two sets of paternal chromosomes and a single set of maternal chromosomes occur as partial moles. Gynoid embryos with two sets of maternal chromosomes and a single set of paternal chromosomes occur as growth-restricted fetuses with abnormal placentas. Imprinting is accomplished by the reversible process of methylation. The role of imprinting in human genetic syndromes was revealed by a cytogenetic paradox. Prader-Willi syndrome is a syndrome of hypotonia at birth, moderate developmental delay, hypogonadotrophic hypogonadism, small hands and feet, uncontrolled appetite, and obesity. In most cases it is associated with a chromosome 15 deletion at 15q11-13. The phenotype of Angelman syndrome, quite different from that of Prader-Willi, is associated with severe mental retardation, inappropriate laughter, ataxic movements, and seizures. It is also associated with a deletion of 15q11-13. The dilemma of how two very distinct syndromes could be caused by the same cytogenetic deletion was solved when molecular studies showed that the deletion of Prader-Willi syndrome was always paternally derived and the deletion associated with Angelman syndrome was maternally derived.17 Individuals who inherit the 15q11-13 deletion paternally have Prader-Willi syndrome because a critical region that is needed for normal development is inactivated or imprinted during maternal meiosis and the corresponding region on the paternal chromosome, which must remain active for normal development, is lost in the deletion. Infants with Angelman syndrome have a maternally derived deletion because the critical region needed for normal development is inactivated or imprinted in the paternally derived chromosome and lost in the maternal deletion.
Uniparental Disomy
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For a subset of patients with Prader-Willi syndrome and Angelman syndrome no cytogenetic deletion can be detected, nor were submicroscopic deletions detected by FISH. Molecular studies did however reveal that both copies of the chromosome were inherited from the same parent. For Prader-Willi syndrome without a deletion both copies of chromosome 15 were maternal in origin.18 For Prader-Willi syndrome the critical region of chromosome 15 is maternally imprinted, and if no paternally derived copy is present, there are no functioning paternal genes for this critical region. Uniparental inheritance of two copies of the same chromosome from one parent is termed uniparental disomy and has been shown to cause genetic morbidity and specific syndromes. Genomic imprinting and uniparental disomy have been reported for a number of chromosomes, including 6, 7, 14, 15, and 16. The most common mechanism causing uniparental disomy is believed to be trisomic rescue (i.e., the loss of a chromosome after a trisomic conception that reestablished the diploid number of 46 chromosomes). On average, two thirds of the time the chromosome lost will be that from the parent who
contributed the extra chromosome. However, one third of the time the chromosome lost will be from the other parent, resulting in uniparental genetic syndromes; it can also be a cause of more common genetic disease. If a parent is a carrier for a recessive genetic disorder and conceives an infant with uniparental disomy, the infant can be affected with the recessive condition if two identical copies of the same chromosome are inherited from the same parent. Several cases of cystic fibrosis have been reported in individuals with uniparental disomy for chromosome 7.19
Trinucleotide Repeat Disorders Fragile X syndrome is one of the most common inherited mental retardation syndromes, occurring in about 1 in 12,000 males and 1 in 2500 females. Fragile X males also have behavioral problems and characteristic features, including a long face with prognathia, large ears, and macroorchidism. Individuals are often diagnosed or labeled with autism. Affected females have a similar but milder phenotype and are developmentally less delayed.20 Fragile X syndrome was originally identified as a fragile site on the X chromosome at Xq27.3 under cell culture conditions deficient in folate. Fragile X syndrome is one of a number of trinucleotide repeat disorders resulting from trinucleotide repeat expansion. The human genome was found to have several types of repetitive DNA. Tandem repeats of trinucleotide sequences can be found in both the coding and noncoding regions of the genome. During replication a trinucleotide repeat sequence can either expand or contract; if expanded beyond a critical copy number, gene function is compromised. Triplet repeat expansion is now recognized as a cause of several human diseases and as a mechanism of inheritance to explain the phenomenon of anticipation. It had been recognized for years that some inherited diseases seem to get more severe in each successive generation. Anticipation had always been considered a bias of ascertainment because each successive generation of an affected family was put under increased scrutiny. Anticipation due to triplet repeat expansion has now been documented for several genetic conditions. Triplet repeat disorders also have another nonmendelian characteristic, dynamic inheritance. Traditionally with single-gene disorders, mutations were considered immutable and passed down through each generation unchanged. We now know that mutations are much more dynamic and can alter when passed through each generation and that the phenotype may also be unstable. Fragile X syndrome is caused by expanded number of CGG repeats in the promoter region of the FMR-1 gene. The inheritance and its consequences can be complex, as shown in Table 5-3.
Table 5-3 Fragile X Syndrome and Trinucleotide Repeat Lengths CGG (n)
Genotype
Male
Female
6–39
Normal
Normal
Normal
40–54
Inconclusive
Normal
Normal
55–200
Premutation
Normal ?
Normal ?
>200
Full mutation
Fragile X
Variable phenotype
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Chapter 5 Reproductive Genetics Normal X chromosomes have between 6 and 54 CGG repeats. Individuals with 40 to 54 repeats are in a gray zone with the possibility of expansion. Males and females with between 55 and 230 repeats carry premutations; males are called transmitting males because they can pass the premutation on to daughters, who are then at risk of expanding the allele to their offspring. In general males only transmit premutations to their daughters. This change of normal CGG repeat number to full mutation is likely a multistep process occurring over several generations. There is now evidence in the literature to suggest that the premutation state in a male carrier may not be harmless. Reports have suggested that a neurologic syndrome can develop with cerebellar and parkinsonian features and decline of cognitive function.21 Although women who are carriers for the fragile X premutation are not cognitively affected, new concerns have also arisen over their long-term functioning. Premutation carriers have shown subtle changes in psychological and cognitive functioning. For women premutation carriers there is also a concern for premature menopause, with a 4% risk by age 30 and a 25% risk for ovarian failure by age 40.22 These authors also reported an imprinting effect for premature ovarian failure with paternally inherited premutations responsible for ovarian failure. Two mechanisms have been proposed to cause the fragile X phenotype when the CGG repeats are expanded. The repeat sequence is located in the 5′ untranslated region of the gene. When this region expands beyond 230 copies of CGG it is hypermethylated and the FMR-1 allele with the expansion is inactivated.23 Not all fragile X chromosomes are methylated. It has also been proposed that the expanded CGG transcript is unstable, such that the mRNA is not transcribed, leading to an absence of the gene product. Other trinucleotide repeat disorders show similar inheritance characteristics as fragile X. These include myotonic dystrophy, which is characterized by myotonia, cataracts, muscular dystrophy, and cardiac arrhythmias. The severity of the disease is directly related to the number of CTG repeats; a severe infantile form of the disease can occur if the expanded repeats are inherited from a mother. Huntington disease is a severe neurologic degenerative disorder caused by CAG repeats in the Huntington disease gene. Individuals are usually affected with 38 or more CAG repeats. Normal individuals have 11 to 34 copies, and premutation individuals carry 34 to 37 copies. The disease is inherited in a dominant fashion and is characterized by progressive dementia, chorea, personality changes, and psychiatric changes. Onset is usually around age 40; it may run a 15-year course to completion. This is usually a tragic situation for families, because most affected individuals have had families and grandchildren before they become aware of the disease.
Somatic Mosaicism In cases of infertility involving Turner’s syndrome and at the time of prenatal diagnosis it is not uncommon to get a mosaic test result. Mosaicism is defined as the presence of two or more cell populations within the same individual. Chromosomal mosaicism results from postzygotic nondisjunction or anaphase lag of a chromosome. Because it is a postzygotic event, it would not be expected to have a recurrence risk beyond that of the random population risk. The significance of mosaicism to an individual or fetus depends on at what time of development
the nondisjunction occurred. Individuals with a low level of mosaicism may never be ascertained. A young girl who is short with a webbed neck and female secondary sexual characteristics may have a significant population of 46,XX cells amid a background of 45,X cells. Mosaicism is not an uncommon finding during cytogenetic analysis of prenatal samples. Mosaicism may arise as an artifact of the culture conditions; this is termed pseudomosaicism. Or, it may arise from the extraembryonic chorion or amnion and represent a true mosaicism. If the mosaicism is confined to the placenta and extraembryonic tissues with a normal diploid embryo, this is termed confined placental mosaicism; the majority of these events, discovered at chorionic villus sampling, result in normal fetuses. Mathematical models have been developed and applied to laboratory techniques to separate true mosaicism from pseudomosaicism.
Germ Cell Mosaicism In prenatal counseling the clinician can be faced with following scenario. An unaffected couple has had a child with an obvious dominantly inherited disorder and want to know the recurrence risk. In most cases the condition is sporadic and the recurrence risk is minimal, the same as the population risk. However, there have been a number of reports of couples having a second child with a dominant condition that cannot be explained as two rare spontaneous mutations. These cases are likely due to germ cell mosaicism. These are thought to be due to spontaneous mutations in the development of the germline in the early gonad. This has been demonstrated for a number of conditions, including osteogenesis imperfecta. Recurrence risks are empirically given up to 3%.
GENETICS OF SEX DETERMINATION AND SEXUAL DIFFERENTIATION With advances in molecular methodologies and the Human Genome Project, it is now possible to identify the molecular mechanisms of sex determination and sexual differentiation. It is also possible to identify specific clinical disorders with abnormalities of these underlying molecular mechanisms. The determination of sex is a sequential process. Chromosomal sex is determined at conception and determines gonadal sex. Gonadal sex then determines sexual differentiation and our secondary sexual characteristics. At any point along this developmental pathway sex determination and sexual differentiation can be altered by mutation. Primordial germ cells initially migrate from the ectodermal layer of the embryo to the urogenital ridge, where the early gonad develops. Genetic sex is determined at the time of fertilization. If conceived with a Y chromosome the primordial gonad develops into a testis. If conceived with two X chromosomes, the primordial gonad develops into an ovary. Sexual differentiation is determined at the time of gonadal development. The bipotent gonads have both Wolffian and müllerian ducts. The bipotent or indifferent gonad will develop into the Sertoli and Leydig cells of the testis in the presence of a Y chromosome and the testisdetermining gene SRY. With an XX chromosome complement, the indifferent gonad will develop into the follicular and theca cells of the ovary.
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Section 1 Basic Science This development takes place on the background of a common, undifferentiated genital blueprint. The blueprint of the undifferentiated primordial genitalia includes paired gonads, paired internal ducts, a genital sinus, labial scrotal folds, and a genital tubercle. The default blueprint for gonadal and genital development is female. In the absence of a Y chromosome and SRY expression the primordial gonad develops into an ovary. The underlying molecular mechanisms for ovarian development are not as well understood as the molecular biology of testicular development. Abnormalities of sex determination and sexual differentiation appear to be determined mostly by mutations in male sexual determination in the background of a female blueprint. The testis, differentiated under the influence of the SRY gene, secrete testosterone, müllerian inhibiting substance (MIS), and an insulin-like growth factor.24 Testosterone induces Wolffian duct differentiation into the vas deferens, epididymis, and seminal vesicles of the male reproductive tract. The MIS inhibits the differentiation of the müllerian ducts. In the absence of the SRY gene and the production of male hormones and in the presence of a female gonad, the müllerian ducts persist and differentiate into the fallopian tube, uterus, cervix, and the proximal portion of the vagina. In the presence of an SRY-determined testis secreting male hormones, the undifferentiated external genitalia develop into a penis and scrotum and male secondary sexual characteristics. In the absence of the SRY gene and the presence of female hormones secreted by the ovary, the undifferentiated external gonad develops into the distal vagina, vulva, clitoris, and female secondary sexual characteristics. This process is depicted in Figure 5-14.
Determination of Sex
Germ cell migration SF-1 WT 1
Formation of urogenital ridge
Bipotential gonad
Gonadal differentiation SOX9
?
SRY Ovary
Testis
Gene Disorders Causing Abnormal Gonadal Development
?
?
Sexual differentiation
Leydig cells
Sertoli cells
Testosterone
MIS
Granular and theca cells
SRY
With the discovery of Klinefelter’s males having an 47,XXY karyotype and the description of Turner’s females as having a 45,X karyotype, it appeared that the presence of a Y chromosome and not the number of X chromosomes resulted in male differentiation in mammalian embryos. The gene on the Y chromosome responsible for male sex determination was named TDF, or testisdetermining factor but was not easily identified. Because the X and the Y chromosome pair and segregate during meiosis just like the autosomes, it had been proposed that the X and Y chromosomes have autosomal-like regions in their distal chromosome arms, or pseudoautosomal regions allowing for pairing and segregation during meiosis. Magenis and coworkers in 1982 reported that 46,XX males have translocations of the Yp region to one of their Xp regions, demonstrating one mechanism for primary sex reversal.25 The occurrence of synapsis and crossovers between the Yp pseudoautosomal regions more proximal to the centromere resulted in the transfer of TDF to the X chromosome and resulted in the construction of deletion maps of the Y chromosome that led to the identification of SRY as the TDF.26,27 The discovery of mutations in the SRY gene in XY pure gonadal dysgenesis confirmed SRY as the candidate gene for TDF.28,29 WT1, Frasier, and Denys-Drash Syndromes
The genes that control the development of the early indifferent
96 gonad have been more difficult to define. These genes may also
X-linked androgen receptor
Dihydrotestosterone
Male external genitalia Figure 5-14
MIS-receptor
Male internal Regression of mullerian duct genitalia (Wolffian duct)
Behavioral differentiation
Process for determination of sex.
be involved in renal development, and many potential regulatory pathways may be involved. WT1, or Wilms’ tumor gene, is a complex gene expressed in early intermediate mesoderm formation prior to urogenital development and when mutated can lead to malformation in renal and gonadal development. Streak gonads, renal abnormalities, and nephrotic syndrome characterize Frasier syndrome. It is caused by mutations in the WT1 gene. This gene codes for a DNA-binding transcription factor with 24 different isoforms due to alternative splicing. Alternative
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Chapter 5 Reproductive Genetics splice donor sites at the end of exon 9 lead to the insertion (+) or deletion (–) of three amino acids—lysine, threonine, and serine (KTS)—between the third and fourth zinc fingers of the transcription factor. XY patients with Frasier syndrome have loss of the +KTS isoform of WT1, causing decreased production of the SRY protein in the urogenital ridge and XY sex reversal. The phenotype is that of a female with gonadal dysgenesis with streak gonads, müllerian duct structures, and nephropathy. The WT1 gene is also associated with the WAGR syndrome and the Denys-Drash syndrome. The WAGR syndrome consists of Wilms’ tumor, aniridia, genitourinary abnormalities of undescended testis and hypospadias, and mental retardation. It is caused by a deletion in the 11p13 region and hemizygosity for the WT1 gene. Individuals with Denys-Drash syndrome are 46,XY with some testosterone production and MIS production. Müllerian duct regression occurs, as does partial testicular development. They have a male phenotype but may have hypospadias and undescended testis and male pseudohermaphroditism. These individuals are +KTS and have mutations outside the KTS region that are believed to affect gonads later in development, causing a less severe phenotype.30 These individuals are at risk for Wilms’ tumors and nephropathy that can lead to end-stage renal disease. SF1
SF1, a steroidogenic factor, is a zinc-finger DNA-binding transcription factor involved with steroid biogenesis. It is expressed during development in the adrenals, gonads, and the pituitary. It appears to have a role in growth and maintenance of the indifferent gonad. SF1 mutations have now been reported with 46,XX sex reversal and adrenal insufficiency shortly after birth.31 DAX1 Gene Mutations and Duplications
DAX1 is an X-linked gene that is expressed in part of the developing embryo, specifically the hypothalamus, pituitary, adrenal, and the gonads.32 Alterations in DAX1 expression are associated with sex reversal and adrenal hypoplasia congenita. DAX1 is a nuclear receptor protein named for dosage-sensitive sex reversal, adrenal hypoplasia congenita, critical region on the X chromosome, and gene 1. DAX1 appears to be part of a class of genes that antagonize male development. Mutations or deletions of the DAX1 gene cause adrenal hypoplasia congenita. Duplications of this gene cause sex-reversed XY females. Mutations in DAX1 cause adrenal hypoplasia congenita with adrenal insufficiency; abnormal pituitary development causes hypogonadotropic hypogonadism. XY Sex Reversal
A duplication of the DAX1 region can cause XY sex reversal and the failure of the testis to develop, or gonadal dysgenesis. The gonad without sperm or oocytes has also been termed a streak gonad. Partial gonadal dysgenesis can occur if some functional testicular tissue remains; the external genitalia may be ambiguous. Sex-reversed males will also have an absence of MIS and müllerian structures will persist, thus distinguishing XY females with androgen resistence, who will not have residual mullerian structures. Patients with XY pure gonadal dysgenesis are at an increased risk of gonadoblastoma, which occurs in 10% to 30% of individuals. Most cases of pure gonadal dysgenesis are caused by mutations of
SRY. The workup should include a karyotype looking for X chromosome deletions, analysis of SRY for mutations, and molecular or FISH testing for DAX1 duplications. Treatment includes estrogen replacement therapy for delayed puberty. Campomelic Dysplasia and SOX9
SOX9 was identified in 1994 as a downstream regulator of male sexual differentiation and was also implicated in skeletal development.33,34 The SOX9 gene is located on chromosome 17q and shares some homology with the SRY gene; hence its name SOX for Sex-related-box. It functions as a transcription factor and in humans is expressed in the testis, kidney, chrondrocytes, liver, and brain. SOX9 plays a significant dose-dependent role in male sex determination, as shown by haploinsufficiency for SOX9 causing either sex reversal or ambiguous sexual differentiation. Increased dosages of SOX9 from duplication have been shown to cause autosomal sex reversal in XX individuals.35 SOX9 also plays a role in MIS activation. In addition SOX9 plays a role in bone and cartilage development and may regulate COL2A1 expression, as seen in the skeletal abnormalities of campomelic dysplasia. Campomelic dysplasia is a sporadic condition characterized by short stature, short limbs, bowed lower limbs, abnormal facies, cleft palate, and often congenital heart disease. It is often a lethal disorder caused by mutations in the SOX9 gene. Inheritance is thought to be autosomal dominant with a significant incidence of new mutations because of the incidence of lethality of this condition. As with any condition with suspected gonadal mosaicism in a parent, the recurrence risk is considered about 3%.
ABNORMALITIES OF THE FEMALE REPRODUCTIVE TRACT Abnormalities of the female reproductive tract are thought to occur in up to 3% of live births.36 Abnormalities of the female reproductive tract affect the fallopian tubes, uterus, cervix, or vagina. The spectrum of abnormalities includes agenesis, atresia, and septations. With a female conception and the differentiation of the bipotential gonad into the ovary, the Wolffian ducts degenerate and the müllerian ducts differentiate into the female reproductive system. The molecular basis for female reproductive tract development in humans is not well described. More is known about the development of the female reproductive tract in mice through knockout studies. The process of development of the müllerian ducts involves apoptosis, or programmed cell death. This process is highly regulated and involves many genes, including the bcl-2 gene, which protects cells from apoptosis. If expression of this gene is absent at a critical time when cells of the fused ducts were to undergo resorption, the septum may persist. A number of human genetic syndromes have been described that affect female reproductive tract formation, differentiation, and regression. Human genetic syndromes involving abnormalities of female reproductive tract formation include Kaufman-McKusick syndrome, Mayer-Rokitansky-Küster-Hauser syndrome, and maturity-onset diabetes of the young type V. Kaufman-McKusick syndrome is an autosomal recessive syndrome originally described in the Amish population with polydactyly, congenital heart disease, and hydrometrocolpos.37 Males can be affected but have only the hand and cardiac findings. The failure to cannalize the uterovaginal plate during embryogenesis produces a transverse
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vaginal septum, causing uterine distension and organ compression. These septa tend to occur in the upper one third of the vagina. This condition is related to Bardet-Biedl syndrome, which is made up of retinopathy, learning disabilities, obesity, polydactyly, renal anomalies, and male hypogonadism.38 The MKKS gene codes for a protein that functions as a chaperonin, a group of proteins that assist in protein folding as the protein is produced from the ribosomes.39 How mutations in the MKKS gene cause Kaufman-McKusick syndrome or the more variable Bardet-Biedl syndrome is not clearly understood. Mayer-Rokitansky-Küster-Hauser syndrome is also known as Rokitansky-Küster-Hauser syndrome. This is a syndrome of müllerian aplasia with an absence of uterus, cervix, and upper vagina. Most cases are 46,XX females with ovaries and normal external genitalia. Renal anomalies and occasional skeletal anomalies are associated with this syndrome. Inheritance is considered autosomal recessive, but a gene for this disorder has not been identified. Treatment consists of creating a neovagina with dilators. MURCS association consists of müllerian aplasia, renal agenesis, vertebral anomalies, Klippel-Feil anomaly, and short stature. It is a sporadic condition and the underlying genetic anomaly has not been identified. Fraser syndrome and MeckelGruber syndrome are also associated with müllerian aplasia. Maturity-onset diabetes of the young type V is an autosomal dominant condition due to mutations in the hepatic nuclear factor 1β (HNF1β) that is associated with renal anomalies and müllerian aplasia. Mutations in this gene can cause müllerian aplasia in the absence of juvenile diabetes. MIS, also known as antimüllerian hormone (AMH), is a member of the transforming growth factor β (TGFβ) family produced by the gonad. Produced by the gonad as testicular sex is determined, müllerian regression is one of the earliest signs of male sexual differentiation. Two types of persistent müllerian duct syndrome have been identified, type I and type II. Type I is caused by mutations in the AMH gene located on chromosome 19. A mutation in this gene is found in about 47% of persistent müllerian duct syndrome families and is an autosomal recessive condition. Type II is caused by mutations in the AMH type II receptor gene, found in about 38% of persistent müllerian duct syndrome families. These individuals have normal AMH levels. Type II is also an autosomal recessive condition. Clinically these individuals are 46,XY with normal male external genitalia. They may have cryptorchidism associated with inguinal hernias; the condition is frequently identified at surgery. Hand-foot-genital syndrome is an autosomal dominant disorder characterized by shortening of the thumbs and great toes, fifth finger clinodactyly, incomplete müllerian fusion with or without a double cervix and longitudinal vaginal septum, and renal anomalies. Males may have hypospadias. Hand-footgenital syndrome is caused by mutations in the HOXA13 gene and is inherited as an autosomal dominant condition.40 Handfoot-genital syndrome is caused by any mutation producing haploinsufficiency in the HOXA13 gene. HOXA13 is a member of the HOX group of transcription factors expressed in distal structures of the limb and the müllerian ducts. Its exact role in müllerian duct fusion and differentiation is unclear. Fryns’ syndrome is a multiple malformation syndrome consisting of cleft lip and palate, CNS abnormalities, renal tract malformations, cardiac defects, and müllerian fusion abnormalities. It is usually lethal and is inherited in an autosomal recessive manner.
Most well-recognized genetic disorders associated with reproductive tract abnormalities are due to deficiencies of key enzymes in the adrenal or testes that are autosomal recessive disorders or an androgen receptor defect. Deficiencies in adrenal enzymes such as 21-hydroxylase will result in a female pseudohermaphrodite (XX karyotype). Deficiencies in enzymes for testosterone synthesis or androgen receptor deficiency will result in male pseudohermaphroditism (XY karyotype).
GENETICS OF MALE INFERTILITY Oligospermia (concentrations <5 million/mL) or azoospermia can be attributed to chromosome abnormalities in approximately 3% to13% of cases.41 The chromosome abnormalities include sex chromosome abnormalities such as 47,XXY, 47,XYY, sex chromosome mosaics, and structural Y chromosome abnormalities. Autosomal chromosome abnormalities include reciprocal translocations, Robertsonian translocations, inversions, and other structural abnormalities. The most common chromosomal abnormality associated with nonobstructive azoospermia is 47,XXY, Klinefelter’s syndrome. The most common gene disorders associated with congenital obstructive azoospermia are mutations of the cystic fibrosis transmembrane conductance regulator gene.
Klinefelter’s Syndrome Klinefelter’s syndrome is the most common cause of hypergonadotropic hypogonadism in the male (high FSH, low testosterone). Although most have a 47,XXY karyotype, some are mosaics. This syndrome is characterized by progressive germ cell and steroid cell depletion and gonadal fibrosis. These patients usually present at puberty with phenotypic abnormalities such as taller than predicted height, small genitalia, and scanty body hair. Androgen therapy is usually initiated. Although these patients are mostly azoospermic, rare immature or mature spermatozoa may be found in the testes. Most mature sperm obtained for in vitro fertilization (IVF) have a normal haploid karyotype so that the offspring should also have a normal karyotype.
Azoospermic Factor (AZF) Microdeletions SRY, the testis-determining gene, is found proximal to the pseudoautosomal region of the short arm of the Y chromosome. There are three azoospermia factor (AZF) regions located on the long arm of the Y chromosome. AZFa, AZFb, and AZFc are found in the proximal long arm of the Y chromosome, as is the DAZ gene. Yq microdeletions of these azoospermia factors account for approximately 10% to 20% of cases of azoospermia and 3% to 10% of severe oligospermia. AZFa and AZFb deletions appear to be more severe than AZFc deletions, which are the most commonly reported deletion. Some men with Yq deletions are fertile. These conditions can be treated with IVF and intracytoplasmic sperm injection (ICSI); however, males conceived from fathers with Yq deletions would be expected to also be infertile (i.e., carry the same microdeletion).
PREIMPLANTATION GENETIC DIAGNOSIS For couples who have had a child die from a congenital genetic disorder or who have conceived and then terminated a wanted
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Chapter 5 Reproductive Genetics but affected pregnancy, the option of prenatal diagnosis and pregnancy termination is not attractive. These couples have welcomed an alternative to traditional prenatal diagnosis and pregnancy termination. Preimplantation genetic diagnosis (PGD) is a prepregnancy form of prenatal diagnosis that combines routine IVF with embryo biopsy to identify affected pregnancies before embryo transfer. PGD has been used in the clinical setting now for almost 15 years. It is now used in the prevention and treatment of three groups of genetic disorders. First, it has been used in the prevention of single-gene recessive disorders when the parents are carriers and the recurrence risk is 25%. Cystic fibrosis was the first such condition to be identified by PGD.42 Individuals affected with autosomal dominant disorders have a recurrence risk of 50%. Examples of autosomal dominant disorders identified by PGD include Marfan syndrome and Huntington disease. Because PGD requires the analysis of DNA from single cells, polymerase chain reaction (PCR) has been the primary method used for the analysis. Most analyses have been done with nested multiplex and fluorescent multiplex PCR. Preimplantation genetic diagnosis has also been used in the diagnosis and prevention of recurrent miscarriages when one partner is a reciprocal translocation or Robertsonian translocation carrier. Two techniques have been used for treating couples who are carriers. For women who are translocation carriers, the first polar body can be biopsied shortly after retrieval, prior to fertilization, and can be evaluated by whole chromosome FISH. Because this technique can only be used with female carriers, the more commonly used technique is that of embryo biopsy. For Robertsonian translocations two FISH probes are required, each located at the telomeric end of the chromosomes involved. For reciprocal translocations three probes with different reporter fluorochromes are required. Two probes must be for the centromeric region of each chromosome, and one probe must be at the telomeric end of one chromosome. Embryos with an unbalanced chromosome complement can be distinguished from those with a balanced complement, either normal or balanced carriers. Unfortunately studies have shown that embryos from translocation carriers have a high incidence of chromosome abnormalities and that pregnancy rates from these couples are low.43,44 There is a long-known relation between maternal age and chromosome abnormalities. It is also recognized that about 60% of pregnancies that miscarry have chromosome abnormalities. Therefore, it is not surprising that PGD has been used in combination with IVF when a couple is at risk of aneuploidy by virtue of advanced maternal age. IVF success rates may be improved when PGD and aneuploidy screening are used in women age 35 to 40.45 Aneuploidy screening has now become the most common indication for PGD. Routine IVF protocols are used for ovarian stimulation and oocyte retrieval. Oocytes are fertilized in vitro or by ICSI and the embryo grown to the six-cell or eight-cell stage. The embryo is then held in culture by a pipette and the zona pellucida opened by either an acid solution or laser beam; a biopsy pipette is inserted to aspirate one or two blastomeres for genetic analysis. An advantage of embryo biopsy is that more than one cell can be biopsied and analyzed. An alternative to embryo biopsy is polar-body biopsy of
an oocyte for carrier status. The group from Chicago has pioneered this technique and shown it to be effective in the identification of single-gene disorders.46 With an estimated 1 in 10 individuals infertile, assisted reproductive technologies (ART) are now responsible for up to 3% of annual births in some Western countries.47 Although ART has been considered safe, registries have been monitoring the children conceived through these technologies. A possible association between ART and Beckwith-Wiedemann syndrome has now been reported by three registries around the world.48 Caused by a defect located at chromosome 11p15, BeckwithWiedemann syndrome is characterized by organ overgrowth, macroglossia, and abdominal wall defects. These studies reported about a fourfold increased risk of Beckwith-Wiedemann syndrome with ART. An association between ART and Angelman syndrome has also been reported. Both of these syndromes are associated with imprinted contiguous gene clusters. About 10% of sporadic cases of Angelman syndrome and about 50% of sporadic Beckwith-Weidemann syndrome are due to epigenetic defects in imprinting. In all cases of Angelman syndrome reported and in 13 of 19 cases of Beckwith-Weidemann syndrome reported, there was loss of methylation of the maternal allele for these genes. This has raised speculation that imprinted genes may be at risk for loss of methylation during preimplantation and that ART may be responsible, whether due to ICSI or the culture conditions in vitro. These reports suggest the need for longitudinal studies of children conceived by ART and long-term evaluation of their development.
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With the advent of the Human Genome Project, we are now able to identify and in some cases treat individuals prior to the onset of a hereditary disorder. The Human Genome Project has revealed new complexities of gene structure and expression. Physicians will need to understand how new technologies identify gene mutations and their impact on human disease. Imprinting, uniparental disomy, mitochondrial inheritance, and trinucleotide repeat disorders have been identified as non-traditional forms of inheritance causing human disease. SRY, SOX9, SF1, WT1, and DAX have been identified as genes critical in gonadal differentiation. The important genes for expression of normal male phenotype that can reproduce are the androgen receptor gene located on the long arm of the X chromosome, the SRY gene on the short arm of the Y chromosome that determines development of the testes, and the AZF genes for spermatogenesis. Klinefelter’s syndrome (XXY) is the most common genetic cause of non-obstructive azoospermia. Microdeletions of AZF region account for about 10% to 20% of cases of azoospermia and 3% to 10% of severe oligospermia. These deletions are passed on to all male progeny. Preimplantation genetic diagnosis can provide prepregnancy diagnosis for single-gene defects and chromosome abnormalities, but there are concerns that congenital disorders associated with imprinting may be increased with PGD.
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Section 1 Basic Science REFERENCES 1. Baird P: Genetic disorders in children and young adults: A population study. Am J Hum Genet 42:677, 1988. 2. Lander E, et al: Initial sequencing and analysis of the human genome. Nature 409:860–921, 2001. 3. Venter J, et al: The sequence of the human genome. Science 291:1304–1351, 2001. 4. Guttmacher AE, Collins FS, Carmona R: The family history—more important than ever. NEJM 351:2333–2336, 2004. 5. Subramanian G, et al: Implications of the human genome for understanding human biology and medicine. JAMA 286:2296–2307, 2001. 6. Liang F, et al: Gene index analysis of the human genome estimates approximately 120,000 genes. Nat Genet 25:239–240, 2000. 7. Dickson D: Gene estimate rises as US and UK discuss freedom of access. Nature 401:311, 1999. 8. Andersson B, Blange I, Sylven C: Angiotensin-II type 1 receptor gene polymorphism and long-term survival in patients with idiopathic congestive heart failure. Eur J Heart Fail 1:363–369, 1999. 9. Sybert VP, McCauley E: Turner’s syndrome. NEJM 351:1227–1238, 2004. 10. Clark BA, Schwartz S: Molecular cytogenetics. In Reed G, Claireaus AE, Cockburn F (eds): Diseases of the Fetus and Newborn, 2nd ed. Vol. II. London, Chapman and Hall, 1995, pp 1121–1129. 11. Maluelidis L: Individual interphase chromosome domains revealed by in situ hybridization. Hum Genet 71:288–293, 1985. 12. Pinkel D, Straume T, Gray J: Cytogenetic analysis using quantitative, high-sensitivity, fluorescence hybridization. Proc Natl Acad Sci USA 85:2934–2938, 1986. 13. Gardner R, Sutherland G: Chromosome abnormalities and genetic counseling. In Motulsky A., et al (eds):Oxford Monographs on Medical Genetics, 3rd ed. Oxford, Oxford University Press, 2004, p 577. 14. Knight S, Flint J: Perfect endings: A review of subtelomeric probes and their use in clinical diagnosis. J Med Genet 37:401–409, 2000. 15. Dickerman L, Park V, Clark BA: Genetic aspects of perinatal disease and prenatal diagnosis. In Fanaroff A, Martin R (eds): Neonatal-Perinatal Medicine: Diseases of the Fetus and Infant, 6th ed. New York, Mosby Year Book, 1997, p 26. 16. Harper P: Practical Genetic Counseling, 5th ed. Oxford, Butterworth Heinemann, 1988. 17. Knoll J, et al: Angelman and Prader-Willi syndromes share a common chromosome 15 deletion but differ in parental origin of deletion. Am J Med Genet 32:285, 1989. 18. Nicholls R, et al: Genetic imprinting suggested by maternal heterodisomy in nondeletion Prader-Willi syndrome. Nature 342:281–285, 1989. 19. Spence J, et al: Uniparental disomy as a mechasnism for human genetic disease. Am J Hum Genet 42:217–226, 1988. 20. Hagerman R, et al: Fragile X Syndrome: Diagnosis, Treatment, and Research. Baltimore, Johns Hopkins University Press, 1991. 21. Leehey M, et al: The fragile X premutation presenting as essential tremor. Arch Neurol 60:117–121, 2003. 22. Hundscheid R, et al: Imprinting effect in premature ovarian failure confined to paternally inherited fragile X premutations. Am J Hum Genet 66:413–418, 2000. 23. Verkerk A, et al: Identification of a gene (FMR-1) containing a CGG repeat coincident with a breakpoint cluster region exhibiting length variation in fragile X syndrome. Cell 1991. 65: p. 905–914. 24. Nef S, Parada L: Hormones in male sexual development. Genes Dev 14:3075–3086, 2000.
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25. Magenis R, et al: Translocation (X;Y)(p22.33;p11.2) in XX males: Etiology of male phenotype. Hum Genet 62:271–276, 1982. 26. Vergnaud G, et al: A deletion map of the Y chromosome based on DNA hybridization. Am J Hum Genet 38:109–124, 1986. 27. Sinclair A, et al: A gene from the human sex-determining region encodes a protein with homology to a conserved DNA-binding motif. Nature 346:240–244, 1990. 28. Berta P, et al: Genetic evidence equating SRY and the testis-determining factor. Nature 348:448–450, 1990. 29. Jager R, et al: A human XY female with a frame shift mutation in the candidate testis-determining gene SRY. Nature 348:452–454, 1990. 30. Little M, et al: DNA binding capacity of the WT1 protein is abolished by Denys-Drash syndrome WT1 point mutations. Hum Mol Genet 4:351–358, 1995. 31. Achermann J, et al: A mutation in the gene encoding steroidogenic factor-1 causes XY sex reversal and adrenal failure in humans. Nat Genet 22:125–126, 1999. 32. McCabe E: Adrenal hypoplasias and aplasias. In Scriver CR, Beaudet AL, Sly WS, Valle D (eds): The Metabolic and Molecular Bases of Inherited Diseases, 8th ed. New York, McGraw-Hill, 2001, pp 4263–4274. 33. Foster J, et al: Campomelic dysplasia and autosomal sex reversal caused by mutations in an SRY-related gene. Nature 372:525–530, 1994. 34. Wagner T, et al: Autosomal sex reversal and campomelic dysplasia are caused by mutations in and around the SRY-related gene SOX9. Cell 79:1111–1120, 1994. 35. Huang B, et al: Autosomal XX sex reversal caused by duplication of SOX9. Am J Med Genet 87:349–353, 1999. 36. Gidwani G, Falcone T: Congenital Malformations of the Female Genital Tract: Diagnosis and Management. Philadelphia, Lippincott Williams & Wilkins, 1999. 37. Kaufman R, Hartmann A, McAlister W: Family studies in congenital heart disease, II: A syndrome of hydrometrocolpos, postaxial polydactyly, and congenital heart disease. Birth Defects Orig Artic Ser 8:85–87, 1972. 38. Beals P, et al: New criteria for improved diagnosis of Bardet-Biedl syndrome: Results of a population survey. J Med Genet 36:4237–4246, 1999. 39. Stone D, et al: Genetic and physical mapping of the McKusick-Kaufman syndrome. Hum Mol Genet 7:475–481, 1998. 40. Mortlock D, Innis J: Mutation of HOXA13 in hand-foot-genital syndrome. Nat Genet 15:179–180, 1997. 41. Dohle G, et al: Genetic risk factors in infertile men with severe oligospermia and azoospermia. Hum Reprod 17:13–16, 2002. 42. Handyside A, et al: Birth of a normal girl after in vitro fertilization and preimplantation diagnositic testing for cystic fibrosis. NEJM 327:905–909, 1992. 43. Committee of the E.P.C.S.: ESHRE Preimplantation Genetic Diagnosis Consortium: Data collection III. Hum Reprod 17:233–246, 2002. 44. Iwarsson E, et al: Highly abnormal cleavage divisions in preimplantation embryos from translocation carriers. Prenat Diagn 20:1038–1047, 2000. 45. Wilton L: Preimplantation genetic diagnosis for aneuploidy screening in early human embryos: A review. Prenat Diagn 22:312–318, 2002. 46. Rechitsky S, et al: Accuracy of preimplantation diagnosis of single-gene disorders by polar body analysis of oocytes. J Assist Reprod Genet 16:192–198, 1999. 47. Evers J: Female subfertility. Lancet 360:151–159, 2002. 48. Gosden R, et al: Rare congenital disorders, imprinted genes, and assisted reproductive technology. Lancet 361:1975–1977, 2003.
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Normal Fertilization and Implantation Navid Esfandiari
INTRODUCTION Fertilization is a complex process in which sperm interacts with the homologous oocyte to create a new individual. The bringing together of two gametes in mammals starts with cells moving through the reproductive tracts of both the male and female organisms until they arrive close to each other in the female reproductive tract. The subsequent interaction between the two gametes requires several steps that result in gamete fusion to produce a zygote, including (1) binding of the spermatozoon to the oocyte coat, (2) oocyte activation, (3) formation of male and female pronuclei, and (4) initiation of cell division and early development. In the past two decades, considerable efforts have been made to identify molecules and pathways utilized during gamete interaction. The interaction and communication between two completely foreign cells is influenced by numerous biologic, physiologic, and genetic factors. Most of what is known about gamete interactions has been derived from animals, and the vast majority of our understanding rests on a murine model. Although many of the molecules involved in fertilization processes that have been identified in the mouse model are conserved in humans, whether this information can be extrapolated to fertilization in humans is a matter of debate. The main experimental method used to study the cellular and molecular mechanisms of sperm– oocyte interactions has been the in vitro fertilization (IVF) technique. With IVF in laboratory animals and humans now a routine procedure, many of the critically important key points in fertilization have been identified. This chapter summarizes the frontiers of knowledge regarding the molecular and cellular mechanisms of fertilization and focuses on basic understanding of the cell biologic processes and molecular events underlying implantation and its relevance to clinical reproductive medicine.
HISTORICAL PROSPECTIVE Before the initiation of modern reproductive and developmental biology in the 17th century, the theory of “seeds” belonging to the pluralistic current of the Pythagorean School led by Anaxagoras of Clazomenae and Empedocles of Akragas was the most believed (5th century B.C.).1 In the field of human reproduction, pluralism means that a fetus results from the mixing of two parental seeds. Hippocrates (c. 460–370 B.C.) believed that “seeds” are produced in all parts of the body, each containing both the masculine and feminine principle; when transmitted to offspring at the time of conception, they cause certain parts of the offspring to resemble
their parents. A century later, Aristotle (384–322 B.C.) rejected Hippocrates’ theory. For him, only the male’s seed contributes to form the fetus; the female’s role in reproduction is to contribute menstrual blood. He had noticed that offspring sometimes resemble their grandparents rather than their parents. It was difficult to understand how seed of tissue and blood could be maintained unnoticed in the parents only to be revealed again in the children. Aristotle proposed that male semen was a mix of ingredients that was not blended perfectly so that materials from previous generations could sometimes get through. Most of Aristotle’s ideas were presented in his treatise, On Generation of Animals. This was the very first complete embryologic work ever written. Moreover, he was the first to illustrate his treatises, which significantly helped to clarify his writings. Galen (130–201 A.D.), who is considered the greatest Greek physician after Hippocrates and founder of experimental physiology, supported Hippocrates’ theory that the seeds of both man and woman contribute to reproduction, but that each contains only one principle.1 In the 17th century, several outstanding findings fueled new scientific developments in modern reproductive biology. William Harvey (1578–1657) was the first to suggest that humans and other mammals reproduced via the fertilization of an oocyte by sperm. However, many authors see Regnier de Graaf (1641–1673) as the founder of modern reproductive biology.2 De Graaf is the one who discovered (1672) the source of oocytes in the testes of women, which we now call ovaries. Five years later the initial discovery of spermatozoa was made by a medical student named John Ham, who told Anton van Leeuwenhoek of the presence of what was termed animalcules in human seminal fluid, thought to have arisen from putrefaction. Leeuwenhoek (1632–1723) was the first to make detailed and accurate identification of sperm as a normal constituent of semen.3 Van Leeuwenhoek proposed that fertilization occurs when the sperm enters the oocyte, but this could not actually be observed for another 100 years because of the quality of microscopes available. Another discovery that revolutionized scientific thinking was by the Italian priest and physiologist Lazaro Spallanzani in 1779. Until that time, our understanding of reproduction was based on our knowledge of how plants grow. It was believed that the embryo was the “product of male seed, nurtured in the soil of the female.” Spallanzani’s experiment established for the first time that for an embryo to develop there must be actual physical contact between the oocyte and the sperm. Spallanzani successfully inseminated frogs, fish, and dogs. The first successful artificial insemination of a woman was recorded just 11 years after Spallanzani’s experiment. In 1790, the renowned Scottish
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Section 1 Basic Science anatomist and surgeon, Dr. John Hunter, reported successful insemination of the wife of a linen draper using her husband’s sperm. These discoveries led to the emergence of modern reproductive technologies, by which the world’s first IVF baby was born just before midnight on 25 July 1978 as a result of continued efforts of Drs. Edwards and Steptoe.
SPERM TRANSPORT IN THE MALE REPRODUCTIVE TRACT Spermatogenesis refers to the complex process of transformation of germline stem cells into sperm cells within the seminiferous tubules of the testes. Spermatogenesis is regulated through endocrine interactions between the pituitary gland and Sertoli cells. This endocrine system is referred to as the hypothalamicpituitary-gonadal axis and involves a series of signaling mechanisms. Two hormones, follicle-stimulating hormone (FSH) secreted by the pituitary, and androgens (i.e., testosterone) produced by the Leydig (interstitial) cells in the testis, control Sertoli cell functions. Once formed within the seminiferous tubules, the immotile spermatozoa are released into the luminal fluid and transported to the epididymis, where they gain the ability to move and fertilize the oocyte.4 The testicular spermatozoa are transported passively to the rete testis, which is a branched reservoir of the openings of the seminiferous tubules. From the rete testis, the spermatozoa are transported to the epididymis via the efferent ductules.5 In mammals, the transit of spermatozoa through the epididymis usually takes 10 to 13 days; in humans the estimated transit time is 2 to 6 days.6 The epididymal segment where most spermatozoa attain their full fertilizing capacity appears to be the proximal cauda. The spermatozoa from that region are capable of moving progressively, which is characteristic of spermatozoa preceding fertilization, and bind to zona-free hamster ova in vitro at a higher percentage than spermatozoa obtained from more proximal locations.7 To attain the capacity to fertilize an oocyte, sperm undergo many maturational changes during its transit in the epididymal duct.4 These include, for instance, changes in plasma membrane lipids, proteins, and glycosylation; alterations in the outer acrosomal membrane; gross morphologic changes in acrosome in some species; and cross-linking of nuclear protamines and proteins of the outer dense fiber and fibrous sheath. The cauda epididymidis (and proximal ductus deferens) are the regions where spermatozoa are stored before ejaculation.7 When ejaculation occurs, the stored spermatozoa with the surrounding fluid are mixed with the alkaline secretions of the male accessory sex glands and deposited in the vagina.
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Spermatozoa are actively transported from the vagina via the cervical canal and the uterine cavity to the ampulla of the oviducts, where fertilization occurs. In the human vagina, the ejaculated semen is deposited near the external cervical opening, where the environment is very acidic due to lactic acid and thus is hostile to spermatozoa.8 The alkaline pH of the ejaculate protects spermatozoa in this acidic environment.9 This protection is, however, temporary, and most spermatozoa only remain motile
in the vagina for a few hours. Thus, the human vagina does not serve as an effective reservoir for spermatozoa and the role of the vagina in sperm transport is transitory at best. There is significant sperm loss in the vagina, and the proportion of ejaculated sperm that enter the cervical mucus in vivo is not known. The spermatozoa are transported into the cervical canal by pressure alterations in the vagina due to the female orgasm, assisted by the normal motility of sperm. Migration of spermatozoa through the cervical canal is thought to be dependent at least in part on sperm concentration, motility, and morphology and is modulated by the physiochemical characteristics of cervical mucus. The interactions between sperm and mucus and the motility of spermatozoa during transport are important; one cause of infertility is presumably impaired sperm movement through the cervical mucus.9 The change in the composition of cervical mucus at midcycle also affects the passage of sperm.10 In ovulatory mucus, sperm penetration and forward progression occur in an efficient and directional manner. In this phase of the cycle, mucin molecules are arranged in a parallel position, directing the spermatozoa into the uterus and also to the cervical crypts where they are stored.11 It is not clear whether the human female reproductive tract has the capacity to establish sperm reservoirs as do the resproductive tracts of other mammals. However, it has been shown that the release of spermatozoa from human cervical crypts may continue for several days.4 In a small percentage of women displaying no sperm in the cervical mucus, however, motile sperm can be recovered from the uterine cavity.12 The uterus seems to be a conduit to sperm transport. The transport of spermatozoa from the cervix to the uterotubal junction is mainly attributable to the myometrial contractility, ciliary movements on the surface of the endometrial cells, and intrinsic sperm motility, although the latter has been shown not to be critical.4 The human endometrium prepares for ovulation by secreting a unique kind of fluid into the uterine lumen. The fluid has a different protein pattern, ionic composition, and volume than at other stages of the cycle.13 This fluid serves to suspend spermatozoa and to keep them viable during the transport process and to remove the coating from the sperm surface as one facet of capacitation. It also contains macrophages that remove dead and nonviable spermatozoa, which in mice is probably the most important physiologic mechanism for the disposal of sperm from the uterus.14 The passage of sperm from the uterus to the fallopian tube is apparently modulated by the uterotubal junction. This segment prevents the entry of nonmotile cells and therefore acts as a selective barrier. The isthmus functions as a sperm reservoir and only a few sperm pass along the fallopian tube to the site of fertilization at any given time.11 The ampulla of the oviduct is the site of fertilization, and motile spermatozoa can be found there up to 85 hours after intercourse. The transport of spermatozoa through the oviducts is a combination of sperm motility, fluid flow, and the contractive movements of the oviduct walls.8
Sperm Capacitation Immediately after deposition in the female genital tract, besides active motility, the sperm are not able to fertilize the oocyte. The physiologic changes that occur to sperm during their transport in the female reproductive tract are collectively referred as capacitation. Capacitation, first described in 1951 (independently
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Chapter 6 Normal Fertilization and Implantation by Chang in the United States and Austin in Australia), was later shown to be a requirement for fertilization. It seems that the initiation and completion of capacitation in human spermatozoa takes place in the cervix.4,9 The molecular events that initiate capacitation include removal of cholesterol from the sperm plasma membrane, increase in membrane fluidity, ion influxes resulting in alteration of sperm membrane potential, hyperpolarization of sperm membrane, increase in tyrosine phosphorylation, and changes in the adenylate cyclase-cAMP system, nucleus, and acrosome.4,15 In humans, capacitation can be mimicked in vitro in defined culture media, the composition of which is based on the electrolyte concentration of oviductal fluid. In most cases capacitation media contain energy substrates such as pyruvate, lactate, and glucose; a cholesterol receptor (such as serum albumin); NaHCO3, calcium, potassium, and physiologic sodium concentrations.
final penetration of the oocyte suggests clinical applications in several areas of human fertility. The fact that once sperm have been capacitated their fertilizable life is shortened in the oviduct is of interest from the standpoint of fertility enhancement. In vitro capacitation of sperm, by removing the seminal plasma and incubating washed sperm in culture media in optimum temperature and a carbon dioxide incubator, allows a precise control of the time of conception and has application for treating some cases of infertility. There are several ways to evaluate acrosomal status in human sperm: (1) methods using transmission electron microscopy, allowing ultrastructural examination of the acrosome; (2) methods using light microscopy based on staining sperm with specific fluorescein plant lectins or various dyes; and (3) methods using a fluorescence-activated cell sorter and fluorescein monocloned antibodies or lectins.
OOCYTE TRANSPORT Hyperactivation and Acrosome Reaction
Capacitation, as a molecular event, occurs both in the sperm head (i.e., the acrosome reaction) and in the tail (i.e., changes in the sperm motility pattern designated as sperm hyperactivation). Sperm hyperactivation occurs before the acrosome reaction.4 The vigorous pattern of movement observed in hyperactivation is a result of physiologic changes in spermatozoa. Compared to sperm in seminal plasma, the speed, velocity, rate of flagellar beating or beat frequency, and mean beat width (lateral head displacement) are increased in capacitated sperm. This pattern of movement enables the spermatozoa to swim in the viscous oviduct fluid and to overcome the physical resistance of the three vestments—cumulus oophorus, corona radiata, and the zona pellucida—which surround the oocyte.16,17 Hyperactivation is a prognostic indicator for IVF; low levels are associated with male infertility and decreased binding to the zona pellucida. The endpoint of capacitation is the acrosome reaction, which occurs when spermatozoa come into close contact with the oocyte in the ampullae of the oviduct. The acrosome reaction is an exocytotic event and enables spermatozoa to penetrate through the zona pellucida and fuse with the oocyte plasma membrane. Many artificial stimuli are reported to trigger the acrosome reaction, either by driving extracellular Ca2+ into the sperm cell (Ca2+ ionophores) or by acting through intracellular second messengers that are involved in the cascade leading to acrosomal exocytosis. The anterior region of the sperm head is covered by the acrosome, containing several hydrolytic enzymes, including proteases, phosphatases, arylsulfatases, and phospholipases. Hyaluronidase and acrosin have been the most extensively studied of these enzymes. The membranes surrounding the nucleus of spermatozoa are the nuclear membrane, the inner acrosomal membrane, the outer acrosomal membrane, and the plasma membrane. In this reaction, the plasma membrane and the outer acrosomal membrane fuse, enabling release of the acrosomal contents important for the events preceding fertilization.4 The acrosome reaction may facilitate recognition, adhesion, and fusion with oocytes by at least three different mechanisms: externalization of ligand proteins (e.g., CD46 on the inner acrosomal membrane); protein migration through the fluid membrane to reach binding sites, such as that for PH-20; or conformational changes of preexisting membrane proteins.18 A knowledge of the capacitation process from the time sperm are deposited in the female reproductive tract until the
The transport of oocytes from the ovarian follicles to the site of implantation has been long recognized as a fundamental step in the reproductive process in the female.19 The fallopian tubes provide the path and means of transport for the ovum from the ovary to the uterus; the duration of ovum transport is the time from its discharge from the follicle until it reaches the normal site of implantation.20 At midmenstrual cycle, approximately day 14 of an idealized 28-day cycle, the surge of pituitary luteinizing hormone (LH) results in the maturation of the oocyte by resumption of meiosis and completion of the first meiotic division. The oocyte nucleus or germinal vesicle undergoes a series of changes that involve germinal vesicle breakdown. The oocyte then enters into the second meiotic division and arrests in the second metaphase or first polar body stage. Meiosis will proceed no further unless the oocyte is fertilized. Meiotic maturation is a vital event in ovulation because it is obligatory for normal fertilization. During the process of meiotic maturation, the cumulus granulosa cells undergo mucification followed by expansion.21 The preovulatory surge of FSH appears to initiate the process of cumulus expansion. The onset of mucification is marked by a dramatic increase in the secretion of mucopolysaccharides into the extracellular spaces. This leads to the dispersal of the cumulus cells and causes the oocyte–cumulus complex to expand tremendously. After ovulation and discharge of the follicular fluid, the oocyte–cumulus complex, consisting of an oocyte surrounded by a zona pellucida, noncellular porous layers of glycoprotein secreted by the oocyte, and granulosa cells (cumulus oophorus), is ovulated from ovarian follicles into the peritoneal cavity and is picked up by the infundibulum of the oviduct.8 The infundibulum is a highly specialized, funnel-shaped portion of oviduct (up to 10 mm in diameter) that bears long, fingerlike extensions of the mucosa (i.e., fimbriae), which sweep over the surface of the ovary; the oocyte–cumulus complex is transported by means of ciliary action along the surface of the fimbriae toward the opening of the oviduct. Cilia that cover the exterior surface of the infundibulum beat in the direction of the ostium and are important in moving the oocyte–cumulus complex into the oviduct. Oocyte pickup is not dependent on a suction effect secondary to muscle contractions, and ligation of the tube just proximal to the fimbriae in the rabbit does not interfere with pickup.22 The mucosal layer of the fallopian tube is lined with
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Section 1 Basic Science a single layer of columnar epithelium that undergoes cyclic changes in response to hormonal changes of the menstrual cycle. There are two distinct types of oviductal epithelium—ciliated and nonciliated secretory epithelium—and the ratio of these two fluctuate in response to ovarian steroids. There are fewer ciliated cells in the isthmus than in the ampullary portion of the tube, whereas they are most prominent in the fimbriated infundibulum. Ciliary activity is responsible for the pickup of oocytes by the fimbrial ostium and for movement through the ampulla, as well as the distribution of the tubal fluid, which supports gamete maturation and fertilization and facilitates gamete and embryo transport. Under the influence of the estrogens of the follicular phase of the menstrual cycle, the cilia of the isthmus beat in the direction of the ovary. At the same time, the cilia of the fimbria and the cilia of the ampulla next to the fimbria beat in the direction of the uterus. In this fashion, the ovulated oocyte will be sequestered within the middle of the ampulla. If sperm enter the uterus at this time, they will be directed into the oviduct and propelled to the awaiting oocyte. It is within the ampulla that fertilization takes place; in humans the oocyte spends about 90% of its stay in the ampulla. After surgical reversal of tubal ligation where a large part of the ampulla was removed, excellent pregnancy rates result along with mildly increased rates of ectopic pregnancies. Pregnancy is possible after reversal of tubal ligation where complete excision of the entire ampula or fimbria was performed, but pregnancy rates are poor. After ovulation and in the presence of an increasing concentration of progesterone, the cilia and myosalpingeal contractions all pulse from the ovary toward the uterus.23 In most species, transport of the fertilized oocyte through the tube requires
approximately 3 days.19 Tubal fluid is rich in mucoproteins, electrolytes, and enzymes. This fluid is abundant in midcycle when gametes or embryos are present and may play an important role during fertilization and early cleavage. Fluid in the tubes is believed to be formed by selective transudation from the blood and active secretion from the epithelial lining.
SUCCESSIVE FERTILIZATION STEPS Fertilization is a series of steps that require immense coordination and communication between the two principal participants, the oocyte and sperm. Each gamete must undergo a series of changes before the final event of union can occur (Figs. 6-1 and 6-2).
Adhesion of Spermatozoa to Oocyte Sperm Penetration of the Cumulus Oophorus
The cumulus oophorus is a specialized layer of granulosa cells that surrounds the ovulated mammalian oocyte. During oocyte maturation, the cumulus cell mass undergoes expansion and mucification, resulting in a well-expanded mass with an extensive amount of extracellular matrix material binding the cells together. The cumulus cells and their matrix are probably involved in several reproductive processes, including pickup of the oocyte–cumulus complex by the oviduct and increasing the chances of an encounter with one of the few sperm that have reached the ampulla of the tube.24 The extracellular matrix consists of a variety of glycoproteins and proteoglycans, with hyaluronic acid being a major component. The mechanisms of sperm penetration through the cumulus mass may involve both mechanical and
Zona pellucida Perivitelline space
8
Polar body Tail Nucleus
Corona radiata
Oocyte
Acrosome 7 Cytoplasm
1 6
2 5
3 4
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Figure 6-1 Fertilization process. (1) Sperm penetration of cumulus cells, (2) attachment to zona, (3) exocytosis of acrosomal contents, (4) penetration to the zona pellucida, (5) entry into perivitelline space, (6) binding and fusion with the oocyte plasma membrane, (7) cortical reaction, and (8) block to polyspermy.
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Chapter 6 Normal Fertilization and Implantation Ovulation and fertilization Day 0
Cleavage and compaction
Day 1
Day 2
Day 3
Blastocyst formation hatching and implantation Day 4
Day 5
Day 6-8
Ampulla Fimbria
Ampulla Isthmus
Ovary
Figure 6-2
Schematic drawing showing the major events from ovulation to the implantation of blastocyst during the first week of human life.
chemical forces. Hyperactivated sperm and membrane-bound hyaluronidase are necessary, and perhaps sufficient, to digest a path through the extracellular matrix of the cumulus cells. The role of hyaluronidase in cumulus mass penetration is controversial because sperm remain largely acrosome-intact during in vitro penetration of the cumulus; sperm with no hyaluronidase can penetrate the cumulus mass and reach the zona pellucida.25 The role of the cumulus cell mass in fertilization is not fully understood. In human fertilization, however, a body of evidence has shown that the presence of the cumulus oophorus is beneficial for fertilization, partly by stimulation of proacrosin conversion to acrosin and initiation of the acrosome reaction. However, removal of the cumulus does not prevent sperm penetration and fertilization. Sperm Interaction with the Zona Pellucida
Eventually after a long journey and penetration of the cumulus mass, the sperm encounters the zona pellucida, the cell typespecific extracellular matrix or coat of the oocyte where speciesspecific gamete recognition is believed to occur. The mammalian zona pellucida is composed of the transcripts of three highly conserved gene families named ZPA, ZPB, and ZPC. The mature products of the genes based on their deduced amino acid sequence are classified as ZP1, ZP2, and ZP3. They are synthesized during oogenesis as a product of the oocyte itself and exhibit heterogeneity because of extensive post-translational modification, including glycosylation.26 Determining the function of individual ZP proteins in humans has been difficult because of the limited availability of native human ZP, and much of the research on the zona pellucida and sperm recognition of the zona pellucida has been carried out using the mouse as a model system. In this
species, the ZP3 protein serves as a sperm receptor molecule, mediating binding of the sperm to the intact zona pellucida. The currently favored model is that O-linked oligosaccharide chains on ZP3 act as a binding epitope for sperm. ZP3 is the primary ligand for sperm, whereas ZP2 in the mouse acts as a secondary sperm receptor that binds acrosome-reacted sperm and ZP1 is considered as a scaffold-like protein that appears to cross-link the ZP2 and ZP3 proteins.27 The complexity of the sperm membrane architecture, along with the difficulty of isolating and purifying it, have made the identification of the spermatozoon counterpart of the oocyte coat ligand a difficult task. Sperm proteins thought to participate in zona binding have been identified by a range of approaches, including inhibitory monoclonal antibodies. Some of these sperm proteins have been specifically implicated as primary sperm receptors for ZP3, whereas others are thought to function as generalized adhesive proteins for the zona matrix. Thus far, among the sperm proteins thought to bind ZP3 oligosaccharides in particular, the sperm surface enzyme β1,4-galactosyltransferase-I (GalT) and two sperm membrane proteins called sp56 and sp95 are the main candidates; GalT satisfies virtually all the criteria expected of a ZP3 receptor.25,28 It presumably recognizes and binds specifically to N-acetylglucosamine residues on ZP3, an enzyme–substrate reaction in which ZP3 serves as substrate. The location of GalT, on the plasma membrane covering the dorsal aspects of the anterior region of the sperm head, is consistent with the inability of acrosome-reacted sperm to bind the zona pellucida because the plasma membrane bearing GalT is lost during the acrosome reaction.29 The binding of ZP3 to sperm activates a range of intracellular signal cascades that culminate in fusion of the plasma membrane and underlying outer acrosomal membrane
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Section 1 Basic Science (i.e., the acrosome reaction).30 The ability of ZP3 to act as an acrosome reaction inducer depends on its polypeptide chain, whereas its ability to act as a sperm receptor rests entirely on its oligosaccharide side chains. ZP3-induced exocytosis of the acrosomal contents proceeds through two sperm-signaling pathways. In the first, ZP3 binding to GalT and other potential receptors results in activation of a heterotrimeric GTP-binding protein and phospholipase C, thus elevating the concentration of cytoplasmic calcium. In the second pathway, ZP3 binding to the same receptor(s) stimulates a transient influx of calcium through T-type channels. In a later phase of the signaling, these initial ZP3induced events produce additional calcium entry through transient receptor potential proteins, candidate subunits of the ion channels, resulting in a sustained increase in cytoplasmic calcium concentration that triggers exocytosis.24,31 Sperm Penetration of the Zona Pellucida
Penetration of the zona pellucida likely involves several factors, including physical forces (e.g., hyperactivated motility of sperm, which involves an increase in flagellar bend amplitude and usually beat asymmetry) and chemical forces (e.g., proteases and glycosidases). The proteases could be sperm surface, membrane-anchored proteases or soluble proteases from the acrosomal contents. The spermatozoon penetrates through the thick zona, cutting a penetration slit that is just as wide as the sperm head.
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After sperm bind to the zona pellucida and the acrosome reacts, they penetrate the zona and enter the perivitelline space, the extracellular region between the zona and the oocyte plasma membrane where the final adhesion in the fertilization process occurs (i.e., adhesion of the sperm plasma membrane to the oocyte plasma membrane). Spermatozoa entering the perivitelline space approach the oocyte surface at an angle that lies somewhere between the vertical and the horizontal. Mammalian oocytes are spherical cells covered with microvilli before fertilization. The sperm head is like a flat dish, and the thickness of the head (~0.2 μm) is a little less than the average distance between oocyte microvilli.32 Spermatozoa, therefore, just pass between the microvilli and make contact with the oocyte close to the cortex through the equatorial segment of the head. In the search for sperm surface proteins that function in this process, most attention has recently been given to the cysteine-rich secretory protein 1 (Crisp1) and members of the ADAM family of metallopeptidase domains (fertilin α [ADAM1], fertilin β [ADAM2], and cyritestin [ADAM3]) that function as cell adhesion molecules. The ADAM family molecules have an adhesion module, the disintegrin domain, which leads directly to the idea that oocytes have an appropriate plasma membrane adhesion partner (i.e., an integrin).33 To better assess the requirement for specific members of the ADAM family in binding (and possibly fusion), knockout mice were constructed that were null for fertilin β, cyritestin, or both (double knockout). Sperm from each of these mouse lines showed dramatically (90%) reduced binding to zona-free oocytes.34,35 Because other sperm proteins may be lost in these knockouts, this reduction in total sperm binding could possibly be caused by loss of an unidentified protein. Initial attachment of the sperm to the oocyte membrane
are reversible and appear to require sperm motility. Sperm tail movement decreases or stops within a few seconds of sperm–oocyte fusion. Electron microscopy shows that the inner acrosomal membrane is later engulfed by the oocyte through a process that appears similar to phagocytosis.33 The sperm tail is also eventually incorporated into the oocyte. The adhesion of sperm to oocyte is frequently cited as likely to be analogous to the mechanism by which leukocytes interact with endothelial cells in a stepwise fashion; sperm–oocyte fusion shares common features with another classical, well-known membrane fusion event between cells and virus particles. Fusion of the sperm and oocyte membrane is followed by the cortical reaction and metabolic activation of the oocyte.
Oocyte Activation As a consequence of successful sperm–oocyte fusion, the oocyte undergoes a series of well-defined morphologic and biochemical endpoints, some of which occur within seconds or minutes of sperm–oocyte plasma membrane interaction and some that occur over the course of several hours.4 These modifications can collectively be termed oocyte activation. One of the earliest events of oocyte activation is an increase in the level of intracellular free calcium in a periodic and oscillatory pattern known as calcium signal. It is clear that this calcium signal induces the release of meiosis, cortical granule exocytosis, zygote formation, and first cell mitosis. The oocyte possesses receptors for sperm glycoproteins in its membrane, and binding the sperm to the receptor alters the receptor so that it might trigger the G-protein cascade or activate tyrosine kinase pathways that then lead to activation of phospholipase C and the production of inositol triphosphate, which mobilizes internal calcium. Alternatively, the sperm may activate the oocyte by direct injection into the oocyte cytoplasm of a sperm-derived protein or factor, called oscillin, which may be the signaling agent for the critical calcium oscillation. This theory helps to explain the clinical success of intracytoplasmic sperm injection (ICSI), in which sperm is introduced directly into the human oocyte cytoplasm and bypasses the activation of the oocyte through binding to a receptor.36 Regardless of the regulatory mechanism, the end results are the resumption and completion of the second meiotic division and ultimately the formation of the female pronuclei. Cortical Reaction and Block to Polyspermy
It is essential that only one spermatozoon fuses and enters the oocyte; therefore, establishment of the block to polyspermy is one of the most critical sequelae of oocyte activation. Entry of more than one sperm into the oocyte cytoplasm at fertilization represents a pathologic condition and leads to the breakdown of development. Under in vivo conditions, sperm–oocyte interaction is regulated in part by the fact that relatively few sperm reach the site of fertilization in the fallopian tube. However, the oocyte must possess mechanisms that can rapidly and precisely eliminate the likelihood of penetration by supernumerary sperm. Fusion of the sperm with the oocyte triggers a release of calcium ions from calmodulin, which results in depolarization of the oocyte plasma membrane, by which fusion of another sperm is prevented.29 The rapid depolarization of the oocyte plasma membrane during fertilization provides an early (fast) block to polyspermy that is only transient and returns to normal within a
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Chapter 6 Normal Fertilization and Implantation few minutes. The initiation of the block to penetration of the zona by other sperm is mediated by the cortical reaction, an exocytotic discharge of the oocyte’s cortical granules that are found just below the oocyte surface and is also apparently triggered by the increase in calcium. Cortical granules contain a variety of hydrolytic enzymes, and these enzymes presumably result in the hardening of the zona pellucida by cross-linking of structural proteins and inactivation of ligands for sperm receptors.37 This process, which is collectively known as the zona reaction, results in the lost of zona ability to bind sperm. The loss of spermbinding activity is due, at least in part, to the release of β-Nacetylhexosaminidase from the oocyte cortical granules, which destroys the GalT-binding sites on ZP3.38 Male Pronucleus Formation and Genomic Union
Fertilization requires accurate cytoplasmic events mediated by the centrosome, which is the cell’s microtubule organizing center.39 The centrosome is a complex organelle composed of many different proteins such as γ-tubulin. Shortly after sperm penetration, maternal γ-tubulin is drawn to the sperm centrosome to assist in the formation of the sperm aster, which is found adjacent and affixed to the sperm nucleus. The continuing elongation of the sperm astral microtubules throughout the cytoplasm allows them to come into contact with the female pronucleus, which is then translocated toward the male pronucleus resulting in pronuclear migration and apposition. Defects in centrosome function during microtubule elongation may result in the failure of normal fertilization. The transformation of the sperm centrosome into a functional zygotic centrosome capable of aster formation suggests that centrosome inheritance in humans is paternal in origin.40 Remodeling of the sperm chromatin into a male pronucleus is guided by the oocyte-produced reducing peptide glutathione and a number of molecules required for the reconstitution of the functional nuclear envelope and nuclear skeleton. After migration and union of the pronuclei, the centrosome duplicates and splits, with each centrosome serving as one pole for the first mitotic spindle. Once the two pronuclei are closely apposed, the nuclear envelope dissolves. The DNA undergoes replication and the chromosomes from each pronuclei are now paired, aligned on the newly formed mitotic spindle, and ready for initiation of first mitotic division through a new cascade of cell cycle-mediating events. Although some of the sperm structures are transformed into zygotic components, the elimination of others is vital to the early stages of embryonic development. The accessory structures of the sperm axoneme, including the fibrous sheath, microtubule doublets, outer dense fibers, and the striated columns of the connecting piece, are discarded in an orderly fashion. During ICSI, which bypasses multiple steps of natural fertilization by introducing an intact spermatozoon into oocyte cytoplasm, the sperm accessory structures that would normally be eliminated before or during the entry of sperm into the oocyte cytoplasm persist and may interfere with early embryonic development, thus decreasing the success rate of assisted reproductive technologies (ART) and possibly causing severe embryonic anomalies.41
IMPLANTATION The molecular events of embryonic attachment to the endometrial epithelium and subsequent invasion into the stroma have long been of interest for reproductive scientists and clinicians. In
most successful human pregnancies, the conceptus implants 7 to 10 days after ovulation. A successful pregnancy in the human requires a receptive endometrium, a functionally normal embryo at the blastocyst stage, a dialogue between the maternal and embryonic tissues, transformation of the endometrium to deciduas, and finally formation of the definitive placenta. Hatching of the blastocyst from the zona pellucida is a key event in mammalian development. The zona pellucida initially prevents the blastocyst from adhering to the oviduct wall, in theory preventing a tubal or ectopic pregnancy. Because the embryo is covered by the zona pellucida until immediately before implantation, all embryo–maternal signaling has to pass the zona and be detectable within it. When the embryo reaches the uterus it must hatch from the zona pellucida; then it can adhere to the uterine wall to establish a pregnancy. On differentiation at the early blastocyst stage, it would appear that trophectoderm is responsible for secreting the zona lysine required for hatching. A trypsinlike protease, termed strypsin, released by the trophectoderm has been proposed to be the zona lysine. On the other hand, impaired uterine receptivity is one of the major reasons for the failed implantation and failure of ART.42,43 The phenomena of implantation and trophoblast invasion are currently considered as the major limiting factor for the establishment of pregnancy.44
Role of Ovarian Hormones In animals, ovarian hormones regulate the development of endometrial receptivity. To prepare for implantation, the endometrium undergoes a precise developmental progression, starting at the proliferative phase under the control of follicular phase estradiol. Estrogen triggers the expression of a unique set of genes in the preimplantation endometrium that in turn control implantation. Expression of the estrogen receptor amplifies the estrogen effects required for uterine cell proliferation and/or differentiation during implantation. Following ovulation, the endometrium is transformed into a specialized secretory structure under the direction of progesterone.45 The cellular actions of progesterone are mediated through intracellular progesterone receptors, which are well-studied gene regulators. It is postulated that hormone-occupied progesterone receptors trigger the expression of specific gene networks in different cell types within the uterus, and the products of these genes mediate the hormonal effects during early pregnancy.
Embryonic Contribution to Implantation In addition to hormonal regulation, increasing evidence demonstrates that embryonic regulation also has a significant impact by inducing reciprocal embryo–uterine interactions that change throughout the implantation process. The preimplantation embryo produces several factors during its development to signal its presence to the maternal organism. The appropriate interaction between the preimplantation embryo and maternal endometrium is at least partly controlled by paracrine cytokines.46,47 Cytokines and growth factors and their corresponding receptors have, on the mRNA level, been detected in blastomeres and in preimplantation embryos from different species as well as in the human endometrium throughout the menstrual cycle. Most of our knowledge of the physiology of implantation has come from animal studies; for obvious ethical reasons, it is not possible to study the
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Section 1 Basic Science process of implantation in humans in detail. However, we focus on biochemical and molecular events that are relevant to humans.
Adhesion Molecules Integrins
APOSITION AND ADHESION Endometrial Receptivity and the Window of Implantation Endometrial receptivity can be defined as the capacity of the uterine mucosa to facilitate successful embryonic implantation. The human endometrium is receptive to blastocyst implantation only during a very short and precise period in the luteal phase. It is the so-called nidation or implantation window, which can be defined as the period of maximum uterine receptivity for implantation.48 In the implantation window, changes occur in endometrial epithelial morphology characterized by the appearance of membrane projections called pinopodes. The time of maximal endometrial receptivity is thought to happen on cycle days 20 to 24 and is manifested by the expression of peptides and proteins that can serve as biomarkers of uterine receptivity.45 Additional information derives from ART cycles in which the window of endometrial receptivity was tested by performing embryo transfer at different times after luteinizing hormone (LH) peak. It has been recently shown that ongoing pregnancy is significantly higher for embryos that implant between cycle days 22 and 24 (postovulation days 8 to 10) than those embryos that are implanted 11 days or beyond after ovulation. Also, the risk of early pregnancy loss increases with later implantation, from 13% among conceptuses that implanted by the day 9 to 52% on day 11, and to 82% after day 11.49
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During the receptive phase, the apical plasma membranes of the epithelial cells lining the uterine cavity lose their microvilli and develop large and smooth apical projections called pinopodes. Pinopodes are progesterone-dependent organelles, appearing as apical cellular protrusions that become visible between days 20 and 21 of the natural menstrual cycle, as shown by scanning electron microscopy in sequential endometrial biopsies.50 The cellular and molecular functions of pinopodes in humans are still unclear; however, tracer experiments in the rat and mouse have shown that these structures perform pinocytosis. They may be also prevent the cilia from sweeping off the blastocyst and may promote withdrawal of uterine fluid, facilitating adhesion of the blastocyst to molecules of the pinopodes, drawing the uterus closely around the embryo.51,52 The disappearance of pinopodes was shown to occur at the time of downregulation of the progesterone receptors.53 Pinopodes last for less than 2 days in all cases, and the timing of their formation depends both on the hormone treatment applied and the patient’s individual response in an IVF cycle. On average, they form on day 20 to 21 in a natural cycle, day 19 to 20 in controlled ovarian stimulation, and day 21 to 22 in a hormonecontrolled cycle. Such short duration and discrete timing of the window of receptivity could significantly affect the outcome of ART. Pinopode appearance, loss of steroid receptors, and maximal expression of αvβ3 integrin, osteopontin, and leukemia inhibitory factor (LIF) and receptor have been demonstrated in the same biopsy, showing a consistent association of pinopode appearance and other receptivity changes.54
Attachment of the embryo may involve temporary adhesion between exposed surface receptors and ligands on the embryonic and endometrial epithelium. The role of integrins in the processes of adhesion and migration makes them attractive potential participants in the complex events of embryo implantation and placentation. Integrins are glycoproteins that serve as cell-surface receptors for the extracellular matrix and connect extracellular cell adhesion proteins to cytoskeletal components. Certain integrin subunits appear to be regulated within the cyclic endometrium,55 and specific alterations were shown in the preimplantation period, suggesting a possible role for α4, β3, and αvβ3 subunits in the establishment of endometrial receptivity. The apical surface of the luminal epithelium expresses the αvβ3 integrin, which localizes on the pinopodes. The loss of αvβ3 is highly associated with endometriosis, retarded endometrial development, and infertility.45,55 The αvβ3 integrin recognizes extracellular matrix ligands that contain the 3-amino acid sequence that has been implicated in trophoblast attachment and outgrowth, and blockade of either the integrin or its ligandbinding sequence reduces implantation in the mouse.56,57 Osteopontin is an endometrial glycoprotein that is recognized by αvβ3 integrin and is present in glandular and luminal epithelium and appears approximately 7days after ovulation on pinopodes.45 Trophinin
Trophinin is an intrinsic membrane protein that is important in trophoblast cell adhesion; bystin and tastin are cytoplasmic proteins that associate with trophinin by presumably forming active adhesion machinery.58 Both trophoblasts and endometrial epithelial cells express trophinin, which mediates apical cell adhesion through homophilic trophinin-trophinin binding. The expression patterns of these molecules are suggestive of their involvement in the initial blastocyst attachment to the uterus as well as in subsequent placental development. Mucins
Mucins are glycosylated molecules found on a great number of tissues, including the endometrial epithelial cells. Largemolecular-weight mucin glycoproteins, including MUC1 through MUC7 and the sialomucin ASGP are present at the apical surface of the uterine epithelium and are secreted into gland lumens. These mucins appear to protect the mucosal surface from infection and the degrading action of enzymes. MUC1, the prominent component, may also play a role in forming a protective barrier in the upper genital tract, preventing infections, and modulating sperm access, but the actual role of MUC1 in human implantation remains to be determined.59 MUC1 has been shown experimentally to inhibit cell-to-cell interactions by steric hindrance of binding interactions mediated by receptors, including integrins. These mucins represent a barrier to embryo attachment and their expression persists in the human uterus during the proposed receptive phase. Pinopodes may function to elevate the implantation surface toward the embryo, free of antiadhesion MUC1. It is also possible that mucin loss is localized to the implantation sites in humans.59,60
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Chapter 6 Normal Fertilization and Implantation Cytokines and Growth Factors The endometrium of most species is now recognized as an important site of production of cytokines and their receptors. The cellular origin of the cytokines varies, but many predominate in the uterine glandular or luminal epithelium or in the decidualized stromal cells.61 Cytokines and growth factors are cell-derived polypeptides and proteins that have the capacity to bind to specific cell-surface receptors and may act as potent intercellular signals, regulating functions of endometrial cells. They regulate cell proliferation, differentiation, and apoptosis by autocrine, paracrine, and endocrine mechanisms.62,63 Cytokines produced by the uterine mucosa and the embryo may play a role in maternal–embryonic interaction, enhancing endometrial receptivity by controlling the expression of adhesion and antiadhesion proteins.64 Interleukins
There is evidence that the interleukin-1 (IL-1) system is important to endometrial and embryonic cross-talk during human implantation.65 The IL-1 receptor is expressed in the endometrium of various species; antagonizing the biologic effects of IL-1 leads to implantation failure in mice. This has been shown to be due to an endometrial rather than an embryonic effect. IL-1 has a possible influence on other systems involved in embryonic implantation, including invasion and angiogenesis, therefore suggesting a role for this cytokine family during early embryonic development.66 Members of the IL-6 family of cytokines include LIF, IL-6, IL-11, cardiotrophin, ciliary neurotropic growth factor, oncostatin M, and the recently discovered cardiotropin-like cytokine novel neurotrophin-1. Gene targeting in mice provided the first indication of a role for the IL-6 family of cytokines in implantation with the generation of mice with a null mutation of the gene encoding LIF. LIF-null female mice were infertile because of failure of blastocyst implantation. More recently, IL-11 signaling has been shown to be required for the uterine decidualization response.67 Vascular Endothelial Growth Factor (VEGF)
VEGF has been shown to increase the proliferative ability of vascular endothelial cells in vitro by acting as a highly specific mitogen for these cell types. After the embryo invades the maternal endometrium, its development is characterized by a dramatic growth of blood vessels coincident with decidualization, development of vascular membranes, and placenta formation.66 Insulin-like growth factor binding protein-related protein 1 (IGFBP-rP1) is highly expressed in the rat uterus around the time of implantation and modulates the proliferation of rat uterine cells and their production of prostacyclin (PGI2) during the peri-implantation period. Furthermore, IGFBP-rP1 significantly stimulated PGI2 synthesis and cyclo-oxygenase-2 mRNA expression in myometrial cells, both of which are essential molecules for successful implantation.68 Known biologic effects of the epidermal growth factor (EGF), VEGF, and fibroblast growth factor in the oviduct and endometrium during the estrous cycle and early pregnancy in pigs are related to cellular differentiation and angiogenesis. This suggests their involvement in the transformation of the endometrium into a decidua, subsequently leading to successful establishment of pregnancy.69
Prostaglandins
Prostaglandins, either maternally or embryo derived, have been thought to be involved in the initial phase of implantation. The principal role of prostaglandins may be to create a mild inflammatory reaction and increase vascular permeability in the endometrium during implantation.70 Cyclo-oxygenase (COX) is the rate-limiting enzyme in the synthesis of prostaglandins and exists in two isoforms: COX-1 and COX-2. COX-1-deficient mice are fertile; mice lacking COX-2 are infertile due to both anovulation and impaired implantation.71 The candidate prostaglandins that participate in these processes and their mechanism of action remain undefined. Using COX-2-deficient mice, it has been demonstrated that COX-2-derived prostacyclin is the primary prostaglandin that is essential for implantation and decidualization.72 Immunostaining for COX-1 found it to be present mainly in the glandular and luminal epithelium; COX-2 was localized to the luminal epithelium and perivascular cells. Treatment with mifepristone significantly reduced the expression of COX-1 in glandular epithelium and COX-2 in luminal epithelium and has been shown to reduce immunostaining for 15-hydroxyprostaglandin dehydrogenase within endometrial glands.73 Human Chorionic Gonadotropin
Recent evidence suggests that human chorionic gonadotropin (hCG), in addition to its well-known endocrine effects on the corpus luteum, may act as a growth and differentiation factor during pregnancy. According to experimental results, its mode of action may be divided into three sequential phases. During the first phase, which begins at the blastocyst stage and lasts until hCG is seen in the serum, hCG acts preferentially in a juxtacrine manner. Administration of hCG may provoke profound effects on paracrine parameters of differentiation and implantation. VEGF, which is important for neoangiogenesis, is stimulated by hCG, suggesting a role for hCG in the control of endometrial vascularization and placentation. The second, endocrine, phase of hCG action is marked by the appearance of hCG in the maternal serum. Rising systemic hCG levels cause a very rapid elevation of serum progesterone, reflecting the rescue of the corpus luteum. Other endocrine functions of hCG include its intrinsic thyrotropic activity as well as modulation of fetal testicular, ovarian, and adrenal function. The third phase may be characterized by the expression of full-length hCG/LH receptors on the trophoblasts themselves. hCG seems to have a variety of local and systemic functions in and outside the embryo–endometrial microenvironment.74
HOX Genes HOX genes are highly evolutionarily conserved and act as regulators of embryonic morphogenesis and differentiation. Mammalian species have at least 39 HOX genes arranged in four clusters, termed HOXA, HOXB, HOXC, and HOXD.75 Specific HOXA genes are important in the development of the müllerian tract. HOXA-10 and HOXA-11 expression rises during the menstrual cycle, increasing dramatically in the midluteal phase, the time of implantation. Recently, studies using targeted mutagenesis have revealed that mice homozygous for HOXA-10 deficiency show implantation failure and embryonic resorption in the early postimplantation period.76 The regulation of a HOX gene by sex
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p38 MAPK) and also lead to NF-κB activation. The expression of COX-2 and matrix metalloproteinase-3 (MMP-3) genes follows after 4 to 6 hours. The steroid hormones, particularly progesterone, which are critical for IGFBP-1 expression, modulate the activity of IL-1β by downregulating MMP-3 activity. IL1β-induced MMP-3 may upregulate IGFBP-1 by initiation of cytoskeletal reorganization through degradation of extracellular matrix.82
INVASION AND PLACENTATION Trophoblast Invasion Endometrial Decidualization
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To protect the mother from the attack of invasive trophoblasts migrating toward the uterine spiral arteries, and in response to ovarian hormones, the endometrial stroma transforms itself into a dense cellular matrix known as the decidua.77 During the process of decidualization, the fibroblast-like mesenchymal cells in the uterine stroma differentiate to epitheloid-like cells. This morphologic change in humans is initiated in the luteal phase under the influence of estradiol, progesterone, and relaxin. The other changes include appearance within the tissue of a specialized lymphocyte subset characterized by an abundant expression of CD56. These cells have been defined in both women and rodents as members of the natural killer (NK) cell lineage and are called uterine (u) NK cells.78 In women, the cells are also called decidual CD56bright cells; a term previously used in mice was granulated metrial gland cells.79 These CD56-positive cells comprise over 90% of the leukocyte population at the time of implantation. The precise function of CD56 cells in the developing decidua is unknown, although they have been proposed to be important in implantation and pregnancy maintenance.80 The mechanism is unclear; however, recognition by NK cells and their receptors and receptor inhibitors of HLA class I molecules, specifically HLA-G on trophoblasts, has been proposed to protect the implanting blastocyst from NK cell lysis.81 Dysregulation of these potentially important events may be involved in either failed implantation or pregnancy failure. Decidual cytokine levels have been characterized primarily at the mRNA level. Among the many genes upregulated during the implantation window, the most prominent include IL-1, CSF, LIF, EGF, and TBF-β.61,64 The secretion of these factors can be modified by gonadal steroids and the blastocyst itself. The blastocyst expresses receptors for these same factors, providing a communicative link from maternal tissue to embryo. The sequence of biochemical and molecular events associated with decidualization is not completely understood. In the baboon, the sequential changes during this period in vivo are characterized by the downregulation of β-smooth actin followed by induction of COX-2 at the implantation site and the expression of insulin growth factor binding protein-1 (IGFBP-1). IGFBP-1 is the predominant protein in decidualized cells and is considered to be a biochemical marker of decidualization. In addition IL-1β, as a possible conceptus-mediated factor, can induce IGFBP-1 expression in the presence of hormones after 3 days of incubation. Current data suggest that IL-1β can activate multiple signaling pathways that either positively (no exogenous cAMP) or negatively (in presence of exogenous cAMP) regulate IGFBP-1 gene expression and decidualization in vitro. Signaling pathways activated by IL-1β following 10 minutes of stimulation result in the phosphorylation of mitogen-activated protein kinase (MAPK, specifically
During the invasive phase of implantation, several events occur, including cytotrophoblast adhesion to the extracellular matrix via cell adhesion molecules, local extracellular matrix proteolysis by MMPs, cellular migration, and inhibition of these processes.63 It is difficult to obtain human material in early gestation; therefore, much of our understanding of the earliest phases of trophoblast invasion has been extrapolated from monkey material.83 Examination of monkey implantation sites has revealed that trophoblasts begin to migrate down into the maternal spiral arteries as early as 10 days after fertilization, and at 14 days, many of the spiral arteries beneath the conceptus are totally occluded.84 Cytotrophoblastic cells are derived from the trophectodermal cells of the blastocyst and represent a heterogeneous population during early pregnancy. Cytotrophoblastic cells follow one of two existing differentiation pathways: Villous cytotrophoblastic cells (vCTBs) form a monolayer of polarized epithelial stem cells that proliferate and fuse to form syncytiotrophoblasts covering the entire surface of the vCTBs. Cytotrophoblastic cells can also break through the syncytium at selected sites (anchoring villi) to form multilayered columns of nonpolarized cytotrophoblastic cells. These motile and highly invasive extravillous cytotrophoblastic cells (evCTBs) are found as cytokeratin-positive cells in the decidua, the intima of the uterine spiral arteries, and the proximal third of the myometrium.85 Trophoblast invasion, like tumor invasion, is due to the active secretion of proteolytic enzymes capable of digesting the different extracellular matrix of the host’s tissues. Serine proteases, cathepsins, and metalloproteinases have been implicated in invasive processes.86 MMPs, also called matrixins, form a family of at least 17 human zinc-dependent endopeptidases collectively capable of degrading essentially all components of the extracellular matrix. According to their substrate specificity and structure, members of the MMP gene family can be classified into four subgroups: gelatinases (digest type IV collagen, the major constituent of basement membranes and denatured collagen), collagenases (digest types I, II, III, VII, and X collagens), stromelysins (digest type IV, V, and VII collagens as well as laminin, fibronectin, elastin, proteoglycans, and gelatin), and membrane-type MMPs. The substrate of the membrane metalloproteinases (MMP-14, MMP-15, MMP-16) is essentially proMMP-2, and these enzymes allow activation of proMMP-2 at the cell surface on the invasive front.87 They are thus appropriately designed for digesting the collagens of the extracellular matrix of the interstitium. Several enzymes are capable of activating the promatrixins, the most well-known being plasmin. The activity of MMPs in the extracellular space is specifically inhibited by tissue inhibitor of metalloproteinases (TIMP), which binds to the highly conserved zinc-binding site of active MMPs at molar equivalence.85 TIMP and broad-spectrum protease inhibitors (such as α2-macroglobulin) of primarily decidual and cytotrophoblast
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Chapter 6 Normal Fertilization and Implantation origin are important in limiting cytotrophoblast invasion and in endometrial stromal receptivity.63 Further penetration and survival depend on factors that are capable of suppressing the maternal immune response to paternal antigens. During implantation, the uterine decidua is invaded by extravillous trophoblast cells that express an unusual combination of HLA class I molecules HLA-C, HLA-E, and HLA-G. The decidua is infiltrated by a population of NK cells that are particularly numerous in the decidua basalis at the implantation site, where they come into close contact with invading extravillous trophoblast cells. It is believed that interaction between these NK cells and extravillous trophoblast cells provides the controlling influence for implantation. On the other hand the increased activity of NK cells has been related to an increased risk of recurrent miscarriage. It seems that the endometrial-derived glycoprotein with immunosuppressive properties, glycodelin-A, may locally inhibit NK cell activity and contribute to protection of the embryonic semi-allograft. Glycodelin-A is the major progesterone-regulated glycoprotein secreted into the uterine luminal cavity by secretory/decidualized endometrial glands.88
Angiogenesis and Vasculogenesis After the embryo invades the maternal endometrium, its development is characterized by a dramatic growth of blood vessels coincident with decidualization, development of vascular membranes, and placenta formation. These active processes involve both angiogenesis, the growth of blood vessels by sprouting from a preexisting endothelium, and vasculogenesis, the in situ formation of primordial vessels from hemangioblasts.89 Human placenta is a rich source of angiogenic substances, and these may play an important role in the regulation of placental vessel formation as well as in maternal vascular adaptation to pregnancy. VEGF expression has been described in villous trophoblasts and fetal macrophages within villous stroma. VEGF increase the proliferative ability of the vascular endothelial cells in vitro by acting as a highly specific mitogen for this cell type. It induces angiogenesis and increases the permeability of blood vessels.90 Another member of the VEGF family, placental growth factor, has been also detected in the villous trophoblast and in the tunica media of larger stem vessels.91 Basic fibroblast growth factor is expressed in the villous trophoblast and can be detected in the conditioned medium of villous tissue explants.92 Proliferin and proliferin-related protein, two prolactin-related peptides expressed by trophoblast giant cells, have been identified as potent regulators of angiogenesis in the murine placenta, although the role of these placental proteins has yet to be evaluated in humans.93 Another recently described angiogenic factor, leptin, is expressed in the placenta and serum during pregnancy and may play a role in vascular development during pregnancy.94
pinopodes are present on day 6 to 8 postovulation, whereas pinopode formation is observed 1 to 2 days earlier in patients undergoing controlled ovarian hyperstimulation. In addition to the individual variations in the timing of pinopode formation, the number of pinopodes also varies between patients, some showing plentiful and others only sparse pinopodes. More interestingly, the number of pinopodes correlated strongly with implantation success after embryo transfer in a subsequent cycle.54 The contemporary approach to ovarian stimulation for IVF treatment results in supraphysiologic concentrations of steroids during the follicular and luteal phases of the menstrual cycle. These sex steroids act directly and indirectly to mature the endometrium, influencing receptivity for implantation. Altered endometrial development has been demonstrated with most of the protocols used for ovarian stimulation.96 A series of studies shows that high estradiol concentrations on the day of hCG administration are detrimental to uterine receptivity.97 Corpus luteum function is distinctly abnormal in IVF cycles, and therefore luteal support is widely used. Since the introduction of gonadotropin-releasing hormone agonists, it has been observed that pregnancy rates increased significantly with luteal-phase supplementation.98 The development of an endometrium receptive to embryo implantation is a complex process that may be altered by inappropriate exposure to sex steroids in terms of timing, duration, and magnitude.99 Embryo transfer has received little clinical attention and has been, until recently, the most inefficient step in IVF. Factors such as contamination of the catheter tip with cervical bacteria, stimulation of uterine contractions during the procedure, the type of catheter, ultrasound guidance during the transfer, and the position of the embryos in the uterine cavity appear to influence implantation rates. Easy and atraumatic transfer is essential for successful implantation; the embryos need to be placed in the middle of the cavity, away from the fundus. Standardization of the transcervical intrauterine transfer of embryos in a large randomized study is needed before definitive conclusions can be drawn.100 There is an evident decline of female fertility with age. This decline is mainly due to increased risk of pregnancy termination either after conception or after embryo implantation. The observation that very good clinical results could be obtained in aged female patients using oocytes donated by younger women has led to the conclusion that the reproductive aging of the women is solely due to a decline of oocyte quality rather than uterine aging and lack of receptivity. Despite some macroscopic possible causes that may play a role in the reduction of age-related endometrial receptivity, many endometrial factors possibly related to its receptivity need to be further studied, especially in older women.101
PEARLS: FERTILIZATION
CLINICAL RELEVANCE ●
Clinical evidence indicates the existence in humans of a narrow window of uterine receptivity, which opens during the midluteal phase. At the same time, formation of pinopodes on the apical membrane of the endometrial epithelial cells occurs. Detection of pinopodes may be extremely useful for the assessment of receptivity in women with history of multiple implantation failure.95 Also it is important to note that in normal fertile women,
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The natural fertilization process in vivo is not yet completely understood; however, the recent advances in assisted reproductive technologies have provided new avenues to the understanding of normal fertilization. Gametes in mammals move through the reproductive tracts of both the male and female until they arrive close to each other in the ampulla of the fallopian tube. The subsequent interaction between the two gametes requires several steps
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that result in formation of a zygote, including binding and penetration of the spermatozoon to the oocyte coat, oocyte activation, formation of male and female pronuclei, and initiation of cell division and early development. Cellular and molecular events after IVF and ICSI differ from those that occur in vivo in several aspects. Despite these differences, normal IVF and ICSI embryos have been produced and have led to numerous healthy births after transfer. Complete fertilization failure is a disappointing experience in IVF cycles. Little is known about the mechanisms of fertilization failure following the IVF or ICSI procedures, but they can be categorized as impaired sperm capacitation and acrosome reaction; failure to attach, bind, and penetrate into the zona pellucida; or failure in signal transduction, oocyte activation, pronuclei formation and apposition, and arrest in the metaphase plate of the embryo’s first mitotic division.
PEARLS: IMPLANTATION ●
The early embryo remains in the tubal ampulla for approximately 80 hours after ovulation, travels through the
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isthmus for approximately 10 hours, and then enters the uterus in the 8-cell or 16-cell stage (morula). The embryo develops into a blastocyst while freely floating in the endometrial cavity 90 to 150 hours after conception. Implantation begins with hatching from the zona pellucida 2 to 3 days after the morula enters the uterine cavity. The endometrium is receptive to the blastocyst during a very short and precise period of time; this occurs as a result of complex action of sex hormones, especially progesterone; embryonic regulatory mechanisms that induce reciprocal embryo–uterine interactions; and the activity of several cytokines and growth factors. Once in contact with the endometrium, the blastocyst becomes surrounded by an outer layer of syncytiotrophoblast, a multinucleate mass with no discernible cell boundaries, and an inner layer of cytotrophoblast made up of individual cells. The syncytiotrophoblast erodes the endometrium, and the blastocyst implants into it. This process is mediated by cytokines and envolves adhesion molecules, mainly integrins. The inability of the embryo to properly implant in the uterus is a significant cause of pregnancy failure after in vitro or in vivo fertilization.
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Chapter 6 Normal Fertilization and Implantation 32. Green DP: Mammalian fertilization as a biological machine: A working model for adhesion and fusion of sperm and oocyte. Hum Reprod 8:91–96, 1993. 33. Evans JP: Fertilin β and other ADAMs as integrin ligands: Insights into cell adhesion and fertilization. Bioessays 23:628–639, 2001. 34. Cho C, Bunch DO, Faure JE, et al: Fertilization defects in sperm from mice lacking fertilin β. Science 281:1857–1859, 1998. 35. Nishimura H, Cho C, Branciforte DR, et al: Analysis of loss of adhesive function in sperm lacking cyritestin or fertilin β. Dev Biol 233:204–213, 2001. 36. Hewitson L, Simerly C, Schatten G: Fertilization. In Fauser BCJM (ed): Reproductive Medicine. New York, Parthenon Publishing, 2003, pp 401–419. 37. Horvath PM, Kellom T, Caulfield J, Boldt J: Mechanistic studies of the plasma membrane block to polyspermy in mouse eggs. Mol Reprod Dev 34:65–72, 1993. 38. Miller DJ, Gong X, Decker G, Shur BD: Egg cortical granule N-acetylglucosaminidase is required for the mouse zona block to polyspermy. J Cell Biol 123:1431–1440, 1993. 39. Hewitson L, Simerly C, Dominko T, Schatten G: Cellular and molecular events after in vitro fertilization and intracytoplasmic sperm injection. Theriogenology 53:95–104, 2000. 40. Simerly C, Wu GJ, Zoran S, et al: The paternal inheritance of the centrosome, the cell’s microtubule-organizing center, in humans, and the implications for infertility. Nat Med 1:47–52, 1995. 41. Sutovsky P, Schatten G: Paternal contributions to the mammalian zygote: Fertilization after sperm–egg fusion. Int Rev Cytol 195:1–65, 2000. 42. Edwards RG: Human uterine endocrinology, and the implantation window. Ann NY Acad Sci 541:445–454, 1988. 43. Edwards RG: Clinical approaches to increasing uterine receptivity during human implantation. Hum Reprod 10(Suppl 2):60–66, 1995. 44. Herrler A, Von Rango U, Beier HM: Embryo–maternal signalling: How the embryo starts talking to its mother to accomplish implantation. Reprod Biomed Online 6:244–256, 2003. 45. Lessey BA: The role of the endometrium during embryo implantation. Hum Reprod 15(Suppl 6):39–50, 2000. 46. Giudice LC: Endometrial growth factors and proteins. Semin Reprod Endocrinol 13: 93–101, 1995. 47. Kauma SW: Cytokines in implantation. J Reprod Fertil Suppl 55:31–42, 2000. 48. Duc-Goiran P, Mignot TM, Bourgeois C, Ferré F: Embryo–maternal interactions at the implantation site: A delicate equilibrium. Eur J Obstet Gynecol Reprod Biol 83:85–100, 1999. 49. Wilcox AJ, Baird DD, Weinberg CR: Time of implantation of the conceptus and loss of pregnancy. NEJM 340:1796–1799, 1999. 50. Nikas G, Drakakis P, Loutradis D, et al: Uterine pinopodes as markers of “nidation window” in cycling women receiving exogenous oestradiol and progesterone. Hum Reprod 10:1208–1213, 1995. 51. Psychoyos A, Nikas G: Uterine pinopodes as markers of uterine receptivity. Assist Reprod Rev 4:26–32, 1994. 52. Stavréus-Evers A, Masironi B, Landgren BM, et al: Immunohistochemical localization of glutaredoxin and thioredoxin in human endometrium: A possible association with pinopodes. Mol Hum Reprod 8:546–551, 2002. 53. Stavreus-Evers A, Nikas G, Sahlin L, et al: Formation of pinopodes in human endometrium is associated with the concentrations of progesterone and progesterone receptors. Fertil Steril 7:782–791, 2001. 54. Nikas G, Aghajanova L: Endometrial pinopodes: Some more understanding on human implantation? Reprod Biomed Online 4(Suppl 3):18–23, 2002. 55. Lessey BA, Damjanovich L, Coutifaris C, et al: Integrin adhesion molecules in the human endometrium. Correlation with the normal and abnormal menstrual cycle. J Clin Invest 90:188–195, 1992. 56. Illera MJ, Cullinan E, Gui Y, et al: Blockade of the αvβ3 integrin adversely affects implantation in the mouse. Biol Reprod 62:1285–1290, 2000. 57. Yelian FD, Yang Y, Hirata JD, et al: Molecular interactions between fibronectin and integrins during mouse blastocyst outgrowth. Mol Reprod Dev 414:435–448, 1995.
58. Fukuda MN, Nozawa S: Trophinin, tastin, and bystin: A complex mediating unique attachment between trophoblastic and endometrial epithelial cells at their respective apical cell membranes. Semin Reprod Endocrinol 17:229–234, 1999. 59. Aplin JD: MUC-1 glycosylation in endometrium: Possible roles of the apical glycocalyx at implantation. Hum Reprod 14(Suppl 2):17–25, 1999. 60. Carson DD, DeSouza MM, Regisford EG: Mucin and proteoglycan functions in embryo implantation. Bioessays 20:577–583, 1998. 61. Salamonsen LA, Dimitriadis E, Robb L: Cytokines in implantation. Semin Reprod Med 18:299–310, 2000. 62. Beier HM, Beier-Hellwig K: Molecular and cellular aspects of endometrial receptivity. Hum Reprod Update 4:448–458, 1998. 63. Giudice LC: Potential biochemical markers of uterine receptivity. Hum Reprod 14(Suppl 2):3–16, 1999. 64. Simón C, Martin JC, Pellicer A: Paracrine regulators of implantation. Baillieres Best Pract Res Clin Obstet Gynaecol 14:815–826, 2000. 65. Simón C, Mercader A, Gimeno MJ, Pellicer A: The interleukin-1 system and human implantation. Am J Reprod Immunol 37:64–72, 1997. 66. Krussel JS, Bielfeld P, Polan ML, Simon C: Regulation of embryonic implantation. Eur J Obstet Gynecol Reprod Biol 110(Suppl 1):S2–S9, 2003. 67. Robb L, Dimitriadis E, Li R, Salamonsen LA: Leukemia inhibitory factor and interleukin-11: Cytokines with key roles in implantation. J Reprod Immunol 57:129–141, 2002. 68. Dominguez F, Avila S, Cervero A, et al: A combined approach for gene discovery identifies insulin-like growth factor-binding protein-related protein 1 as a new gene implicated in human endometrial receptivity. J Clin Endocrinol Metab 88:1849–1857, 2003. 69. Wollenhaupt K, Welter H, Einspanier R, et al: Expression of epidermal growth factor receptor (EGF-R), vascular endothelial growth factor receptor (VEGF-R) and fibroblast growth factor receptor (FGF-R) systems in porcine oviduct and endometrium during the time of implantation. J Reprod Dev 50:269–278, 2004. 70. Chakraborty I, Das SK, Wang J, Dey SK: Developmental expression of the cyclo-oxygenase-1 and cyclo-oxygenase-2 genes in the periimplantation mouse uterus and their differential regulation by the blastocyst and ovarian steroids. J Mol Endocrinol 16:107–122, 1996. 71. Lim H, Paria BC, Das SK, et al: Multiple female reproductive failures in cyclooxygenase 2-deficient mice. Cell 91:197–208, 1997. 72. Lim H, Gupta RA, Ma WG, et al: Cyclo-oxygenase-2-derived prostacyclin mediates embryo implantation in the mouse via PPARδ. Genes Dev 13:1561–1574, 1999. 73. Cameron ST, Critchley HO, Buckley CH, et al: Effect of two antiprogestins (mifepristone and onapristone) on endometrial factors of potential importance for implantation. Fertil Steril 67:1046–1053, 1997. 74. Licht P, Russu V, Wildt L: On the role of human chorionic gonadotropin (hCG) in the embryo-endometrial microenvironment: Implications for differentiation and implantation. Semin Reprod Med 19:37–47, 2001. 75. Taylor HS: The role of HOX genes in human implantation. Hum Reprod Update 6:75–79, 2000. 76. Benson GV, Lim H, Paria BC, et al: Mechanisms of reduced fertility in Hoxa-10 mutant mice: Uterine homeosis and loss of maternal Hoxa-10 expression. Development 122:2687–2696, 1996. 77. Kearns M, Lala PK: Life history of decidual cells: A review. Am J Reprod Immunol 3:78–82, 1983. 78. King A: Uterine leukocytes and decidualization. Hum Reprod Update 6:28–36, 2000. 79. Peel S: Granulated metrial gland cells. Adv Anat Embryol Cell Biol 115:1–115, 1989. 80. Loke YW, King A: Decidual natural killer cell interaction with trophoblast: Cytolysis or cytokine production? Biochem Soc Trans 28:196–198, 2000. 81. LeBouteiller P, Blaschitz A: The functionality of ALA-G is emerging. Immunol Rev 167:233–244, 1999. 82. Strakova Z, Srisuparp S, Fazleabas AT: IL-1β during in vitro decidualization in primate. J Reprod Immunol 55:35–47, 2002.
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93. Yamaguchi M, Imai T, Maeda T, et al: Cyclic adenosine 3′, 5′monophosphate stimulation of placental proliferin and proliferinrelated protein secretion. Endocrinology 136:2040–2046, 1995. 94. Lepercq J, Guerre-Millo M, Andre J, et al: Leptin: A potential marker of placental insufficiency. Gynecol Obstet Invest 55:151–155, 2003. 95. Pantos K, Nikas G, Makrakis E, et al: Clinical value of endometrial pinopodes detection in artificial donation cycles. Reprod Biomed Online 9:86–90, 2004. 96. Sterzik K, Dallenbach C, Schneider V, et al: In vitro fertilization: The degree of endometrial insufficiency varies with the type of ovarian stimulation. Fertil Steril 50:457–462, 1988. 97. Valbuena D, Jasper M, Remohi J, et al: Ovarian stimulation and endometrial receptivity. Hum Reprod 14(Suppl 2):107–111, 1999. 98. Smith EM, Anthony FW, Gadd SC, Masson G: Trial of support treatment with human chorionic gonadotrophin in the luteal phase after treatment with buserelin and human menopausal gonadotrophin in women taking part in an in vitro fertilisation programme. BMJ 298:1483–1486, 1989. 99. Van Der Gaast MH, Beckers NG, Beier-Hellwig K, et al: Ovarian stimulation for IVF and endometrial receptivity—the missing link. Reprod Biomed Online 5:36–43, 2002. 100. Levi Setti PE, Albani E, Cavagna M, et al: The impact of embryo transfer on implantation—a review. Placenta 24(Suppl B):S20–S26, 2003. 101. Ubaldi F, Rienzi L, Baroni E, et al: Implantation in patients over 40 and raising FSH levels—a review. Placenta 24(Suppl B):S34–S38, 2003.
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7
Surgical Anatomy of the Abdomen and Pelvis Tommaso Falcone, Richard L. Drake, and William W. Hurd
INTRODUCTION The goal of reproductive surgery is to treat medical conditions using procedures and techniques least likely to compromise fertility. The goal, whenever possible, is to restore normal anatomy. To reach this goal and minimize complications, every reproductive surgeon requires a thorough knowledge of pelvic anatomy. Knowledge of abdominal wall anatomy is important to ensure safe placement of primary and secondary laparoscopic ports. This chapter reviews practical surgical anatomy of the anterior abdominal wall and pelvis important to gynecologists regardless of surgical approach.
ANTERIOR ABDOMINAL WALL The abdominal wall is made up of four structural layers beneath the skin: (1) subcutaneous tissue and superficial fascial layers, (2) muscles and transversalis fascia, (3) deep fascia of the rectus sheath and the extraperitoneal fascia, and (4) parietal peritoneum (Fig. 7-1). Interspersed among these layers are several important nerves and blood vessels.
Subcutaneous Tissue The layer collectively referred to by most surgeons as subcutaneous tissue is actually made up of superficial (Camper’s) and deep (Scarpa’s) fascia. These loose, fatty connective tissue layers contain the superficial abdominal wall vessels and are the most common site of postoperative wound infections.
Muscles and Transversalis Fascia The abdominal wall is made up of five pairs of muscles. In the midline, the rectus abdominis muscles extend along the whole length of the front of the abdomen from the xiphoid process and costal cartilages of the fifth through the seventh ribs to the pubic crest and pubic symphysis. This broad strap muscle is divided into four segments by three fibrous intersections attached to the anterior, but not the posterior, rectus sheath. This allows the inferior (deep) epigastric vessels to pass along the posterior surface of the muscle without encountering a barrier. The pyramidalis muscle is a small triangular muscle that lies in front of the rectus abdominis at the lower part of the abdomen and is contained within its fascial sheath. It arises from the front of the pubic symphysis and the anterior pubic ligament bilaterally and inserts into the linea alba, between the umbilicus and pubic symphysis. This muscle is commonly absent on one or both sides.
There are three sets of lateral muscles. The external oblique muscle is the most external and arises from the lower eight ribs. The fibers run downward and forward to form aponeuroses that extend anteriorly. Aponeuroses are fibrous membranes resembling flattened tendons that bind muscles to each other or bones. Beneath the external oblique muscle, the internal oblique muscle arises from the lumbar fascia, the iliac crest, and the lateral two thirds of the inguinal ligament and runs upward and forward to form aponeuroses. The most internal of the lateral muscles is the transversus abdominis muscle. It arises from the lateral third of the inguinal ligament, from the anterior three fourths of the iliac crest, from the costal cartilages of the sixth through eighth ribs, interdigitating with the diaphragm, and from the lumbodorsal fascia and ends in front in a broad aponeurosis. Deep to the transversus abdominis muscle is a continuous layer of specialized investing fascia that lines the abdominal cavity and continues into the pelvic cavity, the transversalis fascia.
Deep Fascia of the Rectus Sheath and Extraperitoneal Fascia The rectus abdominis muscle is enclosed anteriorly and posteriorly by fascia known as the rectus sheath. This sheath is formed from fusion of the aponeuroses of all three lateral abdominal muscles. These aponeuroses fuse lateral to the rectus abdominis muscles as the linea semilunares and again in the midline as the linea alba, which extends from the xiphoid process to the pubic symphysis. The arcuate line is a tranverse line midway between the umbilicus and pubic symphsis. Above this line, the aponeuroses of the lateral muscles split to enclose the rectus muscle both anterior and posterior; below this line these aponeuroses all pass anterior to the rectus muscle. Inferiorly, the aponeuroses of the external oblique inserts into the anterior superior iliac spine and stretches over to the pubic tubercle, forming the inguinal ligament. The inguinal canal is about 4 cm long and runs parallel to the inguinal ligament. The inguinal canal has an anterior wall formed by the aponeurosis of the external oblique, an inferior wall formed by the inguinal ligament, a superior wall formed by arching fibers of the internal oblique and transversus abdominis muscles, and a posterior wall formed by the transversalis fascia. A defect, or more precisely a tubular evagination, of the transversalis fascia forms the deep inguinal ring, through which the round ligament enters the inguinal canal. This ring lies midway between the anterior superior iliac spine and the pubic symphysis. Medial to the deep inguinal ring are the inferior epigastric vessels. The opening of the aponeurosis of the external oblique
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Ovarian vessels
Mesovarium Ligament of ovary Sagittal section of broad ligament Uterine tube
Mesosalpinx
Round ligament of the uterus
Mesovarium Ovary
Broad ligament Deep inguinal ring
Mesometrium
Inguinal canal
Uterine artery
Ureter
Superficial inguinal ring Labium majus Figure 7-1 The round ligament is seen entering the deep inguinal ring to course in the inguinal canal and exit through the superficial inguinal ring. The ureter is in close proximity to the ovarian vessels. At laparoscopy, the ureter is seen anterior to the internal iliac for a short distance. (From Drake RL, Vogl W, Mitchell AWM: Gray’s Anatomy for Students. Philadelphia, Elsevier, 2005, p 410, Fig. 5-50.)
superior to the pubic tubercle is the superficial inguinal ring. Through it the round ligament, the terminal part of the ilioinguinal nerve, and the genital branch of the genitofemoral nerve exit the inguinal canal (see Fig. 7-1). Deep to the transversalis fascia and the rectus sheath is a layer of connective tissue separating the transversalis fascia from the parietal peritoneum, the extraperitoneal fascia. This layer contains varying amounts of fat, lines the abdominal cavity and is continuous with a similar layer lining the pelvic cavity. Viscera in the extraperitoneal fascia are referred to as retroperitoneal.
Parietal Peritoneum The parietal peritoneum is a one-cell thick membrane that lines the abdominal cavity and in certain places reflects inward to form a double layer of peritoneum called the mesentery.
Nerves
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There are four categories of nerves that supply the anterior abdominal wall, each of which contain both motor and sensory fibers. The thoracoabdominal nerves originate from T7–T11, travel
anteroinferiorly between the internal oblique and transversus abdominis muscles, and have the following distribution: • T7–T9: superior to the umbilicus • T10: at level of umbilicus • T11: inferior to umbilicus The subcostal nerves originate from T12 and travel anteroinferiorly between the internal oblique and transversus abdominis muscles to innervate the abdominal wall inferior to the umbilicus. The iliohypogastric nerve and ilioinguinal nerve both originate from L1. Like the thoracoabdominal and subcostal nerves, these nerves begin their course anteroinferiorly between the internal oblique and transversus abdominis muscles. However, at the anterior superior iliac spine, they both pierce the internal oblique muscle to travel between the internal and external oblique muscles. The iliohypogastric nerves innervate the abdominal wall lateral and inferior to the umbilicus. The ilioinguinal nerve enters the inguinal canal and emerges from the superficial inguinal ring and is sensory to the labia majora, inner thigh, and groin. These nerves are particularly at risk in lower abdominal incisions, which are the most common causes of abdominal wall pain as a result of nerve entrapment by suture or scar tissue.1 For
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Deep vessels
Superficial vessels
Inferior epigastric
Superficial epigastric
Deep circumflex iliac
Superficial circumflex iliac
Figure 7-2 Anterior abdominal wall blood vessels. (Modified from Hurd WW, Bude RO, DeLancey JOL, Newman JS: The location of abdominal wall blood vessels in relationship to abdominal landmarks apparent at laparoscopy. Am J Obstet Gynecol 171:642–646, 1994.)
this reason, knowledge of the course of the ilioinguinal and iliohypogastric nerves in the anterior abdominal wall can help avoid injury during laparotomy and laparoscopic surgery. Data from cadaveric studies suggest that injury to these nerves can be minimized during laparoscopy by making transverse skin incisions and placing laparoscopic trocars at or above the level of the anterior superior iliac spine.2 In cases of chronic abdominal pain caused by these nerves, an injection of local anesthetic at a site approximately 3 cm medial to the anterior superior iliac spine will often provide relief.
Blood Vessels The major vessels in the anterior abdominal wall can be divided into deep and superficial vessels (Fig. 7-2).3 The superficial vessels include the superficial epigastric and the superficial circumflex iliac vessels. These vessels are branches of the femoral artery and vein. They course bilaterally through the subcutaneous tissue of the abdominal wall, branching as they proceed toward the head of the patient. To avoid vessel injuries, these superficial vessels can often be seen before secondary laparscopic port placement by transillumination of the abdominal wall using the intra-abdominal laparoscopic light source.3 Injury to these vessels during trocar placement can result in a palpable hematoma that will be found to be located anterior to the fascia on computed tomography (CT) scan.4 In unusual cases, the hematoma can dissect down into the labia majora. The deep vessels consist of the inferior epigastric artery and vein, which are also bilateral. These vessels originate from the external iliac artery and vein and course along the peritoneum until they dive deeply into the rectus abdominis muscles midway between the pubic symphysis and the umbilicus. The inferior epigastric vessels are the lateral border of an inguinal triangle called Hesselbach’s triangle. This triangle is bound medially by the rectus abdominis muscle and inferiorly by the inguinal ligament. The course of the inferior epigastric vessels can often be visualized at laparoscopy as the lateral umbilical fold because of the absence of the posterior rectus sheath below the arcuate line
Figure 7-3 Laparoscopic view of peritoneal landmarks and inferior epigastric vessels. The left round ligament is seen entering the deep inguinal ring. Medial to the round ligament at the deep inguinal ring are the inferior epigastric vessels. The peritoneal fold is referred to as the lateral umbilical fold. The peritoneal fold seen medial to the vessels has the obliterated umbilical artery and is referred to as the medial umbilical fold.
(Fig. 7-3).5 Injury to these vessels can result in life-threatening hemorrhage that must be quickly controlled by occluding the lacerated vessels with electrosurgery or precisely placed sutures. If these vessels cannot be visualized (usually because of excess tissue), trocars should be place approximately 8 cm lateral to the midline and 8 cm above the pubic symphysis.3 On the right side of the abdomen, this point approximates McBurney’s point, located one-third the distance from the anterior superior iliac spine to the umbilicus. The corresponding point on left is sometimes referred to as Hurd’s point.
Peritoneal Landmarks Peritoneal Folds
Several useful landmarks can be used to guide the laparoscopic surgeon to avoid injury to important retroperitoneal structures. Two midline and two bilateral pairs of peritoneal folds can usually be seen on the anterior abdominal wall at laparoscopy (Fig. 7-4). The falciform ligament, which is the remnant of the ventral mesentery and contains the obliterated umbilical vein in its free edge, can be seen in the midline above the umbilicus extending to the liver. The median umbilical fold, which contains the urachus, can usually be seen in the midline below the umbilicus extending to the bladder. Although the urachus normally closes before birth, it should be avoided during secondary trocar placement, both because it can be difficult to penetrate and in rare cases can remain patent to the bladder. On each side of the urachus lie the medial umbilical folds. These landmarks contain the obliterated umbilical arteries and extend from the umbilicus to the anterior division of the internal iliac artery. Lateral to these, the lateral umbilical folds can be seen in 82% of patients.5 These are the most important structures to the laparoscopist, because they contain the inferior epigastric vessels and knowing their location can help the laparoscopist avoid injury to these large vessels during placement of secondary laparoscopic ports.
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Ureter Broad ligament
Recto-uterine fold Inferior epigastric artery Recto-uterine pouch
Round ligament of uterus
Umbilical artery Vesico-uterine pouch Median umbilical fold Figure 7-4 The peritoneal reflections onto the urachus (median umbilical ligament), umbilical artery (medial umbilical ligament), and inferior epigastric vessels (lateral umbilical fold) are seen. The two important peritoneal pouches are seen between pelvic organs. (From Drake RL, Vogl W, Mitchell AWM: Gray’s Anatomy for Students. Philadelphia, Elsevier, 2005, p 416, Fig. 5-58A.)
Peritoneal pouches normally exist between the pelvic organs (see Fig. 7-4). The vesico-uterine pouch is located anteriorly between the uterus and bladder. The ventral margin of the bladder can be visualized in approximately half of patients behind the anterior abdominal wall peritoneum and is important for secondary trocar placement, especially after previous abdominal surgery.5 The dorsal bladder margin can often be visualized on the anterior uterus and is used as a landmark during dissections during hysterectomy. The recto-uterine pouch (pouch of Douglas) is located between the anterior surface of the rectum and the posterior surface of the vagina, cervix, and uterus. Endometriosis often involves the recto-uterine pouch and in severe cases, completely obliterates it. Inferiorly, an extraperitoneal fascial plane called the rectovaginal septum extends from the recto-uterine pouch to the perineal body. It lies between the posterior wall of the vagina and anterior wall of the rectum, and when involved with endometriosis can be felt on pelvic examination as nodularity.
laparoscopists who utilize the left upper quadrant primary trocar placement for laparoscopy, an understanding of the anatomy of this area becomes important. For the left upper quadrant technique, the Verres needle and primary trocar are placed into the abdomen 2 cm below the subcostal arch at the midclavicular line. It is important to know what anatomic structures lie close to this area to avoid injury during insertion of the primary cannula. The anatomic structures at risk of injury in this area include (from posterior to anterior) the spleen, splenic flexure of the colon, stomach, and left lobe of the liver. Although relatively few series using the left upper quadrant approach have been reported, it appears that the colon might be the organ at greatest risk of injury using this technique.6 Table 7-1 lists the common body structures and distances from the left upper quadrant point from CT scan data.7
UPPER ABDOMEN
Structures of the posterior abdominal wall anterior to the vertebral column and the pelvic sidewalls are of interest to the reproductive surgeon for several diverse reasons. First, retroperitoneal dissection can be required in these areas during some gynecologic
In the past, the reproductive surgeon had little need to
118 understand the anatomy of the upper abdomen. However, for
POSTERIOR ABDOMINAL WALL AND PELVIC SIDEWALLS
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Chapter 7 Surgical Anatomy of the Abdomen and Pelvis Table 7-1 Distance from Left Upper Quadrant Insertion Site to Common Structures
Structure
No.
Minimum (cm)
Median (cm)
Maximum (cm)
Aorta
49
7.40
11.50
21.50
Vena cava
49
9.30
12.80
20.30
Spleen
47
5.20
12.00
17.60
Stomach
49
1.50
4.40
13.10
Pancreas
49
4.50
8.00
15.60
Liver
49
1.60
4.00
17.00
Left kidney
48
10.00
13.15
22.70
From Tulikangas et al. Anatomy of the left upper quadrant for cannula insertion. J Am Assoc Gynecol Laparosc 7: 211–214, 2000.
procedures, such as treatment of deep endometriosis and removal of pelvic masses adherent to the peritoneum. Secondly, an understanding of the course of retroperitoneal nerves is a useful reminder to the surgeon to be aware of the position of self-retaining retractor blades during laparotomy, because permanent nerve injury can result from prolonged pressure on these structures. Finally, with the use of closed techniques for primary laparoscopic trocar placement, injury to the retroperitoneal structures can occur, and knowledge of this anatomy is essential for effective and expedient management. Like the anterior abdominal wall, the posterior abdominal wall and pelvic sidewalls contain multiple, well-defined muscles. Other important structures include several large nerves and blood vessels and the ureters.
Muscles Several muscles of importance in the posterior abdominal wall lateral to the vertebral column can be seen lateral to the pelvic inlet. The diaphragm forms the roof of the abdomen and extends down to form the most superior aspect of the posterior abdominal wall. The psoas major muscle runs longitudinally from the transverse processes of the upper lumbar vertebrae to the lesser trochanter of the femur and makes up a large part of the posterior and medial wall. The tendon of the psoas minor muscle can be seen anterior to the psoas major muscle during dissection near the external iliac vessels. The quadratus lumborus muscle runs lateral and posterior to the psoas major muscle from the transverse process of the lumbar vertebrae and ribs to the iliac crest. The iliacus muscle spans the iliac fossa. Finally, the piriformis muscle begins at the anterior surface of the sacrum and passes through the greater sciatic foramen to attach to the greater trochanter of the femur. It lies immediately beneath the internal iliac vessels.
Nerves Multiple nerves enter or transverse the pelvic sidewalls. Deep nerves of the pelvis, such as the superior and inferior gluteal nerves, supply several of the pelvic muscles but are not visible during reproductive surgery. Likewise, the obturator nerve traverses the pelvis. The obturator nerve originates at spinal cord levels L2–L4 and descends in the psoas major muscle until the
pelvic brim, when it emerges medially to lie on the obturator internus muscle lateral to the internal iliac artery and its branches (Figs. 7-5 and 7-6). It descends on the obturator internus muscle to enter the obturator canal and exits in the thigh. It is sensory to the medial side of the thigh and motor to the muscles in the medial compartment of the thigh (the adductor muscles). It can easily be seen during pelvic sidewall dissections for endometriosis or lymph node dissection. The genitofemoral nerve (from spinal cord levels L1 and L2) lies on the anterior surface of the psoas muscle (Fig. 7-7). It has two branches, the femoral and genital. The femoral branch enters the thigh under the inguinal ligament, and the genital branch enters the inguinal canal. The genitofemoral nerve is sensory to the skin over the anterior surface of the thigh. Injury to this nerve is seen after appendectomy or when the fold of peritoneum from the sigmoid colon to the psoas muscle is incised. The femoral nerve (spinal cord levels L2–L4) is not usually seen during pelvic surgery but may be injured by compression at laparotomy. It is a branch of the lumbar plexus and descends within the substance of the psoas major muscle, emerging at its lower lateral border. The nerve continues between the psoas and iliacus muscles and then passes posterior to the inguinal ligament to supply the skin of the anterior thigh region as well as many of the muscles in the anterior compartment of the thigh. Prolonged pressure on the psoas muscle may cause temporary or permanent damage to the femoral nerve. For this reason, caution must be taken when using self-retaining retractors to make certain that the lateral blades do not put pressure on the pelvic sidewalls. The sacral and coccygeal nerve plexuses are located anterior to the piriformis muscle beneath the branches of the internal iliac artery. The most important nerves in this area are the sciatic and pudendal nerves. The sciatic nerve (from spinal cord levels L4–S3) lies anterior to the piriformis muscle and exits the pelvic cavity through the greater sciatic foramen inferior to the muscle. Anterior to the sciatic nerve are many branches of the internal iliac artery. The pudendal nerve (from spinal cord levels S2–S4) is also found anterior to the piriformis muscle and exits the pelvic cavity inferior to the piriformis muscle through the greater sciatic foramen. It courses around the sacrospinous ligament and ischial spine, through the lesser sciatic foramen, and into the perineum. Endometriosis may involve the sciatic nerve at this level and cause pain syndrome related to the course of this nerve.
Blood Vessels The major blood vessels are perhaps the most important structures of the pelvis (see Fig. 7-5). Successful pelvic surgery requires a thorough understanding of their anatomy. The aorta bifurcates at the level of L4 into the left and right common iliac arteries. The common iliac artery passes laterally, anterior to the common iliac vein to the pelvic brim. At the lower border of L5, the common iliac artery divides into internal and external iliac branches. The external iliac artery gives off only two branches, the inferior epigastric artery and the deep circumflex iliac artery, and then, after passing under the inguinal ligament, becomes the femoral artery, which is the primary blood supply to the lower limb. The internal iliac artery supplies all of the organs within the pelvis and sends branches out through the greater sciatic foramen to supply the gluteal muscles. A branch also exists through the greater sciatic foramen and re-enters the lesser
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Anterior truck of internal iliac artery Median sacral artery (from aorta in abdomen)
S1
Umbilical artery
S2 S3
Superior vesical artery
S4
Obturator nerve Obturator artery
Middle rectal artery
Uterine artery
Dorsal artery to clitoris artery
Inferior gluteal artery Internal pudendal artery Vaginal artery
Figure 7-5 The obturator nerve is seen coursing over the pelvic brim when it emerges medially to lie on the obturator internus muscle lateral to the internal iliac artery and its branches. The anterior trunk of the internal iliac artery gives off several branches: a common trunk that typically divides into the umbilical artery and uterine artery, the obturator artery, the internal pudendal artery, the vaginal artery, and the middle rectal artery. The anterior trunk terminates as the inferior gluteal artery. The umbilical artery gives off the superior vesical artery. (From Drake RL, Vogl W, Mitchell AWM: Gray’s Anatomy for Students. Philadelphia Elsevier, 2005, p 428, Fig. 5-64.)
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Figure 7-6 Laparoscopic view. Two branches of the anterior trunk of the left internal iliac artery, the uterine artery and the umbilical artery, are seen medial to the left obturator nerve. The nerve lies on the obturator internus muscle. The relationship of the vessels with the ureter (retracted by the instrument) is seen.
Figure 7-7 The peritoneum over the left external iliac artery and psoas muscle has been removed. The instrument is on the left external iliac artery and points to the left genitofemoral nerve that is splitting into the two branches. Lateral to the nerve is the left psoas minor tendon.
sciatic foramen to supply the perineum. After passing over the pelvic brim, the internal iliac arteries divide into anterior and posterior trunks. The posterior trunk consists of three branches: the ilolumbar artery, the lateral sacral artery, and the superior
gluteal artery. These vessels are closely related to the nerve plexus on the piriformis muscle. The superior gluteal artery is the largest branch of the internal iliac artery and supplies the muscles and skin of the gluteal region. Accidental occlusion of
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Chapter 7 Surgical Anatomy of the Abdomen and Pelvis this artery during uterine fibroid embolization can result in necrosis of the gluteal region. The anterior trunk of the internal iliac artery has several branches that are routinely seen during laparoscopic surgery. The obliterated umbilical artery is a fibrous band seen on the anterior abdominal wall as the medial umbilical fold and can be traced back to its juncture with the internal iliac artery. At this point, the uterine artery can be identified as it arises from the medial surface of the internal iliac. The superior vesical artery also arises near this point and courses medially and inferiorly to supply the superior aspect of the bladder and the distal ureter. The uterine artery is of particular importance to the reproductive surgeon. After the umbilical artery emerges from the anterior trunk of the internal iliac artery, the uterine artery runs parallel to and then crosses over the ureter at the level of the uterine cervix in the base of the broad ligament. The vaginal artery most commonly originates from the uterine artery, but may arise independently from the internal iliac artery. The uterine, vaginal, and ovarian arteries anastomose with each other, with branches of the internal pudendal artery, and with the corresponding contralateral arteries. The other important branches of the anterior trunk of the internal iliac artery are the obturator artery, which courses laterally and anteriorly toward the obturator canal, and the middle rectal, internal pudendal, and inferior gluteal arteries. The inferior gluteal artery is the largest branch of the anterior trunk.
Ureters The ureters measure approximately 25 to 30 cm from kidney to bladder and are occasionally duplicated on one or both sides for all or part of this course. Their abdominal segment lies behind the parietal peritoneum on the medial part of the psoas major muscle and crosses the common iliac vessels at the level of their bifurcation at the pelvic brim.
The pelvic segment of the ureters runs down on the lateral wall of the pelvic cavity, along the anterior border of the greater sciatic notch immediately beneath the parietal peritoneum. Here the ureters form the posterior boundary of the ovarian fossae. They then run medial and forward between the two layers of the broad ligaments. It is here that the ureters run parallel to the uterine arteries for about 2.5 cm before crossing under the arteries and ascending on the lateral aspects of the uterine cervix and upper part of the vagina to reach the bladder. The average distance between the ureters and cervix is greater than 2 cm.8 However, the reproductive surgeon should remember that this distance can be less than 0.5 cm in approximately 10% of women, which explains in part the relatively common occurrence of ureteral injury during hysterectomy (Fig. 7-8). On reaching the base of the bladder, the ureters run obliquely through the wall for approximately 2 cm and open by slitlike orifices at the angles of the trigone. When the bladder is distended during cystoscopy, these orifices are approximately 5 cm apart. When the bladder is emptied, this distance decreases by 50%.
MUSCLES OF THE PELVIC FLOOR The pelvic floor consists of two closely related muscle layers: the pelvic diaphragm and the deep perineal pouch. Damage to these muscles or their innervation is common during vaginal delivery. A thorough understanding of this anatomy is imperative for anyone doing vaginal surgery for prolapse or urinary incontinence.
Pelvic Diaphragm The pelvic diaphragm forms the muscular floor of the pelvis and is made up of the levator ani and coccygeus muscles that are all attached to the inner surface of the minor pelvis (Fig. 7-9).9 The levator ani is composed of three muscles. The innermost
Bladder
Ureters
Cervix
B A Rectosigmoid Figure 7-8 Schematic representation of the proximity of the ureter to the cervix. A, Sagittal view of pelvic organs. B, Transverse view of pelvic organs at the level of the cervix. (From Hurd WW, Chee SS, Gallagher KL, et al: Location of the ureters in relation to the uterine cervix by computed tomography. Am J Obstet Gynecol 184:336–339, 2001.)
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PRESACRAL SPACE
Figure 7-9 Laparoscopic view of the levator ani muscle. The rectum has been transected. The hysterectomy is complete and sutures are seen in the vagina. The ureters are seen laterally entering the pelvis. Most of the levator ani muscle seen here is iliococcygeus. The fibers are directed toward the sacrum and coccyx as well as toward the opposite muscle to form a midline raphe.
puborectalis muscle is attached to the pubic symphysis and encircles the rectum. The thicker, more medial pubococcygeus muscle runs from the pubic symphysis to the coccyx. This muscle is attached laterally to the obturator internus muscle by a thickened band of dense connective tissue called the arcus tendineus. The fusion of these bilateral muscles in the midline is called the levator plate and forms a shelf on which the pelvic organs rest. When the body is in a standing position, the levator plate is horizontal and supports the rectum and upper two thirds of the vagina above it. The thinner, more lateral iliococcygeus muscle runs from the arcus tendineus and ischial spine to the coccyx. The posterolateral margin of the pelvic diaphragm is the coccygeus muscle, which extends from the ischial spine to the coccyx and lower sacrum. Weakness or damage to parts of the pelvic diaphragm may loosen the sling behind the anorectum and cause the levator plate to sag. Women with prolapse have been shown to have an enlarged urogenital hiatus on clinical examination.10
Perineal Membrane, Deep and Superficial Perineal Pouches
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The deep perineal pouch bridges the gap between the inferior pubic rami and the perineal body. It closes the urogenital hiatus and has a sphincter-like effect at the distal vagina. It provides structural support for the distal urethra and also contributes to continence because it is attached to periurethral striated muscles. Knowledge of the anatomy of this area is necessary for surgical procedures that involve creation of a neovagina in patients with androgen insensitivity syndrome or correction of ambiguous genitalia. The perineal membrane and the deep perineal pouch are musculofascial structures located over the anterior pelvic outlet below the pelvic diaphragm. The perineal membrane is a fascial layer attached to the ischiopubic rami. There are openings in this fascia for the urethra and vagina. The deep perineal pouch
Reproductive surgeons are sometimes required to operate in the presacral space when performing a presacral neurectomy to control chronic pelvic pain. In this space lies the superior hypogastric plexus that contains both sympathetic and parasympathetic nerve fibers. In reality this plexus is more prelumbar than presacral. The superior hypogastric plexus divides into two branches at about the level of the bifurcation of the aorta near L4. In addition to visceral afferent fibers from the uterus, these nerve trunks also carry parasympathetic fibers that stimulate bladder contraction and modulate activity of the distal colon. It is for this reason that presacral neurectomy can result in both bladder and bowel dysfunction. Another risk of presacral neurectomy is blood vessel injury. The left common iliac vein makes up the left superior margin of the presacral area as it lies inferior to the bifurcation of the aorta and anterior to the vertebra; it can be injured during this dissection. The median sacral vessels originate from the aortic bifurcation and descend in the midline into the presacral area. Bleeding from these vessels and the presacral venous plexus can be potentially life-threatening.
PELVIC VISCERA The pelvic viscera includes the rectum, urinary organs, and the internal genitalia, including the vagina, uterus, uterine tubes, and ovaries.
The Rectum The rectum of the adult is approximately 12 to 15 cm in length. It begins at the rectosigmoid junction in front of S3 and ends at the anorectal junction at the level of the tip of the coccyx. Unlike the colon, it lacks taeniae coli, haustra, and omental appendices. The upper third of the rectum projects into the peritoneal cavity anteriorly and laterally. At its midpoint, the anterior peritoneum of the rectum extends onto the fornix of the vagina to form the rectouterine pouch. The distal one third is completely retroperitoneal. The blood supply to the rectum includes the superior rectal artery, a branch from the inferior mesenteric artery; the middle rectal artery, a branch from the internal iliac artery; and the inferior rectal artery, a branch from the internal pudendal artery. The rectum is innervated by sympathetic fibers from the inferior hypogastric plexus, parasympathetic fibers that leave the sacral spinal cord (S2–S4) as pelvic splanchnic nerves and enter the inferior hypogastric plexus before passing to the rectum, and sensory fibers from the rectum that join the inferior hypogastric plexus.
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Chapter 7 Surgical Anatomy of the Abdomen and Pelvis Vagina The vagina is a musculomembranous sheath 7 to 9 cm in length that extends anteroinferiorly from the uterine cervix to the vestibule. Because the cervix enters the vagina along the anterior wall, the posterior wall is about 1 cm longer than the anterior wall. Anterior and posterior to the cervix are vaginal fornices. Intraperitoneally, the vagina is separated from the rectum by the rectouterine pouch and from the bladder by the vesicouterine pouch (see Fig. 7-4). The vagina receives its blood supply from the uterine, vaginal, and middle rectal arteries, which form an extensive anastomotic network. Innervation of the vagina is from the inferior hypogastric plexus and pelvic splanchnic nerves.
Uterus The uterus is a fibromuscular organ that varies in size and weight according to life stage and parity. The uterus is divided into a body (corpus) and cervix. The part of the body of the uterus above the uterine tube is called the fundus. In a nulliparous woman the uterus is about 8 cm in length from the external os to the fundus, 5 cm in width at the fundus, and 2 to 3 cm deep anteroposteriorly. It weighs between 40 and 100 g. The uterine cavity is triangular in shape, and the anterior and posterior walls approximate each other. Because the uterine cavity is a virtual space, ultrasound assessment of the uterus will only show a cavity when it is distended with fluid. The length of the uterine cavity changes according to life stage, in part because of the profound effect of hormones on uterine size. In premenarchal girls the uterine length from the external os to the fundus is 1 to 3 cm. The cervix occupies two thirds of the uterine length in prepubertal girls and only one third after menarche. During the reproductive years, the expected length of the cavity is about 6 to 7 cm, which is important to remember when introducing instruments into the uterine cavity during endometrial biopsy, hysteroscopy, or embryo transfer. In postmenopausal women the uterus decreases to about 3 to 5 cm long. The uterine wall is made up of three layers: endometrium, myometrium, and serosa. The endometrium is hormonally responsive and varies in thickness from 5 to 15 mm during a single menstrual cycle during the reproductive years. After menopause, it should be less than 5 mm in thickness as measured by ultrasound. The myometrium consists of three to four indistinct layers of smooth muscle approximately 1 to 1.25 cm thick during the reproductive years. It is thickest in the midportion of the uterine corpus and thinnest near the opening of the uterine tube. The outermost layer consists of mostly longitudinal fibers. The middle layer consists of circular and oblique fibers and includes most of the blood vessels and loose connective tissue. The innermost layer is composed of mostly longitudinal fibers that are continuous with the uterine tubes and ligaments that surround the uterus. The uterine blood supply is from the uterine artery, a branch of the internal iliac artery. The uterine artery courses along the lateral border of the uterus and forms extensive anastomoses with the ovarian and vaginal arteries. Approximately 6 to 10 blood vessels penetrate the uterus from the uterine artery and run circumferentially as the anterior and posterior arcuate arteries. Vessels from the sides anastomose in the midline, but no large
blood vessels are found in the midline. Doppler studies have shown that the arcuate arteries are at the periphery of the uterus. The arcuate arteries supply the radial branches that penetrate deeply the myometrium to reach the endometrium. These radial arteries give rise to the spiral arteries of the endometrium. Incisions on the uterus made during myomectomy should take into consideration the anatomy of the uterus. An incision made vertically in the midline is less likely to divide the large uterine vessels on the lateral border of the uterus. However, vertical uterine incisions may transect several arcuate arteries.
Uterine Tubes The uterine tubes are contained within the uppermost margin of the broad ligament and measure about 10 to 12 cm (see Fig. 7-1). Each tube is divided into several distinct anatomic segments: intramural (or interstitial), isthmic, ampullary, and infundibulum. The internal diameter of the tube ranges from less than 1 mm at the intramural portion to up to 10 mm at the infundibulum. The intramural portion of the tube is usually 1.5 cm long and may be tortuous. The tubal ostium where it opens into the uterine cavity can be seen at hysteroscopy at each angle of the fundus. The isthmic portion is often the site of tubal ligation and therefore the site of tubal anastomosis. The lumen is approximately 0.5 mm. Although magnification is required for anastomosis, the subsequent pregnancy rates are highest for procedures done in this area. The ampulla comprises two thirds of the length of the tube and has four to five longitudinal ridges. It is the site of fertilization and thus the most common site of ectopic pregnancy. Although the lumen is much larger here, the pregnancy rates after anastomosis are lower. The infundibulum is the distal section of the tube. It is not attached by peritoneum and is open to the peritoneal cavity. Its delicate finger-like projections are called fimbriae. The tubal wall consists of three layers: mucosa, muscularis, and serosa. The muscular layer has a somewhat indistinct external longitudinal layer and inner circular layer of smooth muscle. The intramural portion has no anatomic sphincter, but closure is sometimes seen during hysteroscopy. The blood supply to the tube runs in the mesosalpinx and consists of branches from the uterine and ovarian arteries.
Ovaries The ovaries are ovoid structures suspended from the posterior aspect of the broad ligament by the mesovarium (see Fig. 7-1). This fold of peritoneum contains an extensive complex of blood vessels. The infundibulopelvic ligament (suspensory ligament of the ovary) enters the ovary along its superior pole and carries the ovarian vessels, lymphatics, and nerves. These vessels are in close proximity to the ureter at the pelvic brim (see Fig. 7-1). The ovarian ligament is located on the inferior pole of the ovary. The ovary is attached to the broad ligament by the mesovarium. It has a rich vascular supply. An arcade of vessels is formed from the anastomoses of the uterine and ovarian vessels. Theses vessels, called helicine because of their highly coiled structure, course through the mesovarium into the medulla. Veins then drain the medulla from a plexus seen in the mesovarium. Dissection
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The suspensory ligament of the ovary, often referred to as the infundibulopelvic ligament, is a lateral continuation of the broad ligament beyond the uterine tube that connects the ovary to the pelvic brim and contains the ovarian artery and vein. The ureter crosses beneath these vessels near the point where this ligament joins the pelvic sidewall.
Fascial Ligaments
PELVIC FASCIAS AND LIGAMENTS The pelvic viscera are attached to the pelvic sidewalls by (1) peritoneal folds, (2) condensations of pelvic fascia, and (3) remnants of embryonic structures. In the past, it was believed that these structures supported the uterus and prevented genital prolapse. Thus many of these structures were designated as ligaments. However, it has become clear that none of these structures provide significant support for the pelvic viscera in the presence of pelvic floor defects.
The cardinal ligament is a connective tissue condensation lateral to the cervix that is bordered anteriorly and posteriorly by the leaves of the broad ligament and inferiorly by the pelvic floor. It is continuous with the paracervix, a dense fibrous sheath around the lower cervix and the upper vagina, and is attached to the pelvic walls laterally. It usually contains major branches of the uterine vessels. The uterosacral ligament is a connective tissue band arising from the posterior paracervix that fans out to attach to the sacrum and rectum. It contains some smooth muscle fibers.
Peritoneal Folds
Gubernacular Ligaments
The broad ligament is a double-layered transverse fold of peritoneum that encloses the uterus and uterine tubes and extends to the lateral walls and pelvic floor (see Figs. 7-1 and 7-4). It is made up of the mesometrium lateral to the uterus that encloses the uterine vessels and the ureters, the mesovarium that attaches the ovary to the broad ligament posteriorly, and the mesosalpinx that connects the uterine tube near the base of the mesovarium.
The ovarian ligament runs in the broad ligament and attaches the medial pole of the ovary to the posterior-lateral uterine surface beneath the uterine tube. The round ligament is the forward continuation of the uterine attachment of the ovarian ligament. This fibromuscular structure traverses the deep inguinal ring and terminates as fibrous strands in the connective tissue of the labium majus.
REFERENCES 1. Stultz P: Peripheral nerve injuries resulting from common surgical procedures in the lower abdomen. Arch Surg 117:324–327, 1982. 2. Whiteside J, Barber M, Walters M, Falcone T: Anatomy of ilioinguinal and iliohypogastric nerves in relation to trocar placement and low transverse incisions. Am J Obstet Gynecol 189:1574–1578, 2003. 3. Hurd WW, Bude RO, DeLancey JOL, Newman JS: The location of abdominal wall blood vessels in relationship to abdominal landmarks apparent at laparoscopy. Am J Obstet Gynecol 171:642–646, 1994. 4. Hurd WW, Pearl ML, DeLancey JO, Quint EH, et al: Laparoscopic injury of abdominal wall blood vessels: A report of three cases. Obstet Gynecol 82:673–676, 1993 5. Hurd WW, Amesse LS, Gruber JS, et al: Visualization of the epigastric vessels and bladder before laparoscopic trocar placement. Fertil Steril 80:209–212, 2003.
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6. Patsner B: Laparoscopy using the left upper quadrant approach. J Am Assoc Gynecol Laparosc 6:323–325, 1999. 7. Tulikangas PK, Nicklas A, Falcone T, Price LL: Anatomy of the left upper quadrant for cannula insertion. J Am Assoc Gynecol Laparosc 7:211–214, 2000. 8. Hurd WW, Chee SS, Gallagher KL, et al: Location of the ureters in relation to the uterine cervix by computed tomography. Am J Obstet Gynecol 184:336–339, 2001. 9. Herschorn S: Female pelvic floor anatomy: The pelvic floor, supporting structures, and pelvic organs. Rev Urol 6(Suppl 5):S2–S10, 2004. 10. Delancey JO, Hurd WW: Size of the urogenital hiatus in the levator ani muscles in normal women and women with pelvic organ prolapse. Obstet Gynecol 91:364–368, 1998.
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8
Pathology of Reproductive Endocrine Disorders Charles V. Biscotti and Tommaso Falcone
INTRODUCTION An appreciation of the relationship between form and function is important for understanding of female reproduction. An awareness of histologic changes associated with both the normal ovulatory cycle and reproductive diseases allows the physician a better understanding of pathophysiology and potential treatment. This chapter begins with an examination of the histologic changes in the endometrium associated with a normal ovulatory cycle. This is followed by an illustrated survey of common gynecologic diseases of the reproductive organs that are most likely to present to the reproductive surgeon.
UTERUS
Most clinicians perform endometrial biopsy in the midluteal phase at about the time implantation is thought to occur. However, the original reports on secretory endometrial dating recommend a biopsy 3 days before the expected menses. Histologic criteria are then used to determine where the endometrial response would be in relation to ovulation (Table 8-1 and Figs. 8-1 and 8-2). Several assumptions in the original concept of dating the endometrium besides the assumption of ovulation on day 14 increased the variation found with this method. For example, another assumption was that the length of the luteal phase is 14 days.1 In reality, there is a normal variation in luteal phase length of several days. In addition, the original description fixed the time of ovulation with the onset of the period after the biopsy. The onset of ovulation can be more accurately determined using
Endometrium The endometrium is functionally divided into two layers: the basalis and the functionalis. Both layers are composed of stroma and glands. The stroma is composed of stromal cells, vessels, and white blood cells thought to be lymphocytes or macrophages. Cyclic changes occur in both endometrial glands and stroma in response to a changing endocrine environment.
Table 8-1 Criteria for Histologic Dating Gland mitosis Pseudostratification of nuclei Subnuclear vacuoles Edema Stromal mitosis
Endometrial Dating
Decidual reaction in stroma
Endometrial dating refers to the determination of how closely the histologic characteristics of the endometrium match what is expected on the corresponding day of the menstrual cycle. In the past, this approach was one of the standard tests in an investigation of causes of infertility and pregnancy loss. However, the accuracy of this test has been questioned because abnormal results can be observed in cycles that eventually prove to result in a viable pregnancy. Endometrial dating can be performed both before and after ovulation. Preovulatory phase (proliferative phase) endometrial dating is described as menstrual days, early follicular, midfollicular, and late follicular, but is not very precise. Postovulatory phase (secretory phase) endometrial dating has become the standard and is usually reported within a 2-day range, although the accuracy of this dating methodology is the subject of some debate. For secretory phase endometrial dating, ovulation is used as the primary reference point. Originally, ovulation was assumed to occur on day 14 of the menstrual cycle and the days after ovulation numbered accordingly. Some pathologists refer to ovulation as “day 0” and report the postovulation day as the number of days after ovulation.
Leukocyte infiltration Secretion
Figure 8-1 Midluteal phase endometrium has early spiral arteriolar formation (center) arising in edematous stroma. Endometrial glands are tortuous with basal nuclei, absence of mitotic activity, and intraluminal secretions.
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Figure 8-2 Late luteal phase endometrium has large areas of coalescent predecidua and a conspicuous lymphoid infiltrate, giving the stroma a dimorphic appearance.
current modalities, such as determination of the midcycle urinary luteinizing hormone surge or ultrasonic identification of the collapse of a follicle. The accuracy of the former is approximately 85%; of the latter, 95%. Additional intrinsic inaccuracies of dating resulted from intraobserver and interobserver variation. This variation is typically about 2 days. For these reasons, a 2-day difference between the histologic estimation and the actual interval since ovulation is considered within normal limits. Recently a detailed analysis on endometrial dating demonstrated that the histologic criteria used are not as temporally distinct as originally thought, and thus do not provide an accurate method to detect a luteal phase defect. In one study, approximately 20% of fertile couples had a delay of more than 2 days.2 A between-cycle variation of more than 2 days was found in 30% to 60% of patients if the biopsy was performed between day 6 and day 13 after ovulation.
Figure 8-3 The microscopic appearance of the endometrium exposed to oral contraceptives varies, depending on the dose of progestin. Typically, stroma having a weak progestin effect surrounds simple, straight, widely spaced, and inactive-appearing endometrial glands.
Figure 8-4 The presence of plasma cells defines chronic endometritis. Typically, the endometrium resembles a proliferative-type endometrium. The stroma often has a spindled appearance.
Endometrial Response to Exogenous Hormones
The endometrium responds to exogenous hormones with specific morphologic changes. With oral contraceptives, the progestin effect dominates because progestins decrease estrogen receptors. As a result, endometrial glands atrophy over time. The appearance of the stroma depends on the dose of progestin. Typically, a weak pseudodecidual response will occur (Fig. 8-3). Exposure to progestins only (e.g., medroxyprogesterone acetate) will show similar gland pattern but usually a more prominent stromal pseudodecidual response due to higher progestin dose. The selective estrogen receptor modulator tamoxifen is anti-estrogenic at some sites but has a weak estrogenic agonist effect on the endometrium. The endometrium usually atrophies, but variable hyperplasia and, rarely, adenocarcinoma can occur due to the weak estrogen agonist effect. Endometritis
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Chronic endometritis is sometimes demonstrated in endometrial biopsies for infertility or recurrent pregnancy loss. This is characterized by infiltration of plasma cells (Fig. 8-4). Chronic pelvic inflammatory disease, intrauterine devices, and postabortion complications are also associated with chronic endometritis. Although rare in the United States, endometrial tuberculosis
may sometimes be found during a biopsy for infertility and is characterized by granulomas (Fig. 8-5). Abnormal Uterine Bleeding
The biopsy of an endometrium for dysfunctional uterine bleeding in women may show a range of abnormalities of the endometrium (Fig. 8-6). In the reproductive age group organic lesions such as polyps and leiomyomas or a normal endometrium are often found. Pregnancy-related endometrial changes or premalignant or malignant changes may be found in this age group. In adolescent and perimenopausal age patients, anovulatory cycles are one of the most common causes of abnormal uterine bleeding. During anovulatory cycles, the endometrium is proliferative and may exhibit some breakdown. Thrombosis of vascular sinusoids also commonly occurs. Anovulatory cycles create a milieu of unopposed estrogen; therefore, hyperplasia and carcinoma can result. Pregnancy-related Endometrial Changes
Early pregnancy, both intrauterine and ectopic, is characterized by hypersecretory endometrium (Fig. 8-7). However, hypersecretory
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Figure 8-5 Tuberculosis endometritis causes granulomatous inflammation. In reproductive age women, granulomas tend to be cellular but not markedly necrotic. The case illustrated here has a well-formed nonnecrotizing granuloma (right) adjacent to an endometrial gland. In postmenopausal patients, tuberculous endometritis causes striking necrotizing granulomatous endometritis.
Figure 8-7 Hypersecretory endometrium has closely packed endometrial glands with marked intraglandular budding (ferning) and ongoing glandular secretions with secretory vacuoles. Hypersecretory endometrium characterizes early pregnancy; however, this change is not specific for gestation.
Figure 8-6 This endometrial biopsy specimen illustrates gland–stromal asynchrony. The endometrial glands have consistent and conspicuous subnuclear vacuoles corresponding to approximately postovulatory day 3 (cycle day 17). In contrast, the endometrial stroma has striking stromal edema corresponding to approximately postovulatory day 8 (cycle day 22). This appearance of gland–stromal asynchrony is the most common secretory phase morphologic abnormality.
Figure 8-8 By the end of the first trimester, the hypersecretory glandular changes resolve. Subsequently, gestational endometrium has mostly simple widely spaced endometrial glands, separated by stroma with a prominent progestin effect (true decidual change), as seen in this example.
endometrium is not specific for pregnancy, and similar changes can be seen with persistent corpus luteum cyst, double corpora lutea, or rarely as a drug effect. By the end of the first trimester, endometrial glands involute and the stroma shows a prominent decidual reaction (Fig. 8-8). Other histologic changes associated with gestation include the Arias-Stella reaction (Fig. 8-9) and optically clear nuclei (Fig. 8-10). The Arias-Stella reaction refers to cytonuclear changes, including voluminous, vacuolated cytoplasms surrounding enlarged, hyperchromatic, polyploid nuclei that includes massively enlarged forms. The Arias-Stella reaction occurs almost exclusively in gestational endometrium associated with pregnancy or gestational trophoblastic disease; however, this reaction can rarely occur as a response to hormonal therapy in nonpregnant patients. The
optically clear nuclei associated with gestation can resemble herpes virus inclusions.
Endometriosis Endometriosis is defined as the presence of endometrial glands and stroma at an extrauterine site. Although most commonly located in the pelvis, endometriosis can occur at a remarkable variety of extrapelvic sites (Table 8-2). Endometriotic lesions can invade neural tissue. The stromal component can undergo smooth muscle metaplasia. Hyperplasia of smooth muscle, especially the bowel, is characteristic. Endometriotic lesions are sensitive to sex hormones and undergo cyclic changes. The appearance of endometriosis on visual inspection at laparoscopy or laparotomy is quite variable and ranges from blue nodules to red or white lesions. The microscopic appearance also varies, depending on secondary changes of fibrosis and hemorrhage (Figs. 8-11 and 8-12). Endometriotic
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Section 1 Basic Science Table 8-2 Reported Sites of Endometriosis Implants Pelvic Locations Ovaries, uterine ligaments, vagina, cervix Pelvic peritoneum Rectovaginal septum Urinary system Bladder Ureters Gastrointestinal Rectum Rectosigmoid colon Nerves Sciatic nerve Lymph nodes
Figure 8-9 This photomicrograph illustrates the Arias-Stella reaction. The Arias-Stella reaction is a cellular and nuclear change characterized by nuclear enlargement and hyperchromatisma resulting from polyploidy. The enlarged hyperchromatic nuclei are typically arranged in an apical portion of the endometrial glandular cells. This nuclear change can be mistaken for malignancy; however, the Arias-Stella reaction, unlike adenocarcinoma, typically affects only scattered cells within the endometrial glands and mitotic figures are absent or at most infrequent.
Figure 8-10 This endometrial gland has the optically clear nuclear appearance seen with pregnancy (center top).
Extrapelvic Locations Gastrointestinal, including colon, appendix, and small bowel Inguinal hernia sacs Skin of umbilicus and inguinal area Surgical incisions, especially following cesarean delivery Lung and pleura Kidney Liver
Figure 8-11 In this example, endometriosis, characterized by well-preserved endometrial glands and stroma, involves the muscularis of the uterine tube.
lesions should be differentiated microscopically from the benign serous tubules of endosalpingiosis. Importantly, endometriosis must also be distinguished from well-differentiated adenocarcinoma. The latter lacks endometrial stroma and has malignant cellular features. However, endometriosis can rarely undergo malignant change. Estimates for malignant transformation of endometriosis range from 0.3% to 0.8% for surgical series of ovarian endometriosis.3 In one study almost 80% of endometriosis-associated malignancies arose in the ovary.4 Malignancies arising in endometriosis are usually adenocarcinomas, almost always endometroid or clear cell type. Rarely sarcomas such as endometrial stromal sarcoma or müllerian adenosarcoma occur.5
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Adenomyosis refers to endometrial glands and stroma located deep within the myometrium. The etiology and pathogenesis of
Figure 8-12 Over time, secondary changes predominate due to repeated cycles of hemorrhage and fibrosis. In this example, dense fibrous tissue borders a more recent hemorrhage (top).
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Chapter 8 Pathology of Reproductive Endocrine Disorders adenomyosis are poorly understood. Smooth muscle cell hyperplasia and hypertrophy are commonly found. Many cases of adenomyosis are associated with leiomyomas, and it is difficult to ascertain which pathology is responsible for the symptoms. Histologically, thickened rims of myometrial smooth muscle surround benign endometrial glands and stroma (Fig. 8-13).
leiomyomas. Mitotic figures are infrequent, and the nuclei are uniform (Fig. 8-15). Leiomyoma variants (Table 8-3) include cellular, apoplectic, bizarre (Fig. 8-16), mitotically active, hyaline, cystic, myxoid, and infarcted. All of these variant appearances can occur in benign
Table 8-3 Leiomyoma Variants
Leiomyoma Leiomyomas are benign monoclonal tumors of smooth muscle. These tumors commonly have cytogenetic abnormalities, such as rearrangements of 6p or deletion of 7q, which are identified in 40% of uterine leiomyomas. The myometrial tissue adjacent to the leiomyoma is cytogenetically normal. Grossly, leiomyomas appear as circumscribed masses of whorled, bulging, rubbery, usually light tan masses (Fig. 8-14). Microscopically, fascicles of bland spindled cells characterize
Cellular Apoplectic Bizarre Mitotically active Hyaline degeneration Cystic Myxoid Infarcted
Figure 8-13 Benign endometrial glands and stroma deep within the myometrium characterize adenomyosis. These adenomyotic foci are often associated with hyperplasia of the adjacent smooth muscle.
Figure 8-14 This leiomyoma well illustrates the usual gross appearance, characterized by sharp circumscription and a gray tan homogeneous cross-section.
Figure 8-15 Microscopically, leiomyomas have fascicles of uniform spindle-shaped cells with elongated, spindle-shaped, blunt-ended nuclei. Note the lack of nuclear pleomorphism. Importantly, necrosis, other than infarct-type necrosis, is absent and mitoses are infrequent.
Figure 8-16 Markedly enlarged, pleomorphic, and hyperchromatic nuclei characterize bizarre (symplastic) leiomyomas. This nuclear change has not been associated with malignant behavior in the absence of other features of malignancy.
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Figure 8-17 This infarcted leiomyoma has well-developed coagulation necrosis characterized by loss of nuclei and prominent cytoplasmic eosinophilia.
Figure 8-18 A uterine leiomyosarcoma with prominent tumor cell necrosis. Tumor cell necrosis, as illustrated here, is an important diagnostic criterion for leiomyosarcoma. Tumor cell necrosis is characterized by a sharply circumscribed focus of necrosis lacking a marginal healing zone.
tumors, but some, especially myxoid, mitotically active, and bizarre, should prompt a thorough search to exclude malignancy. A common treatment for leiomyomas is gonadotropin-releasing hormone (GnRH) agonists. A 50% decrease in uterine volume is seen over a 3-month period, although leiomyomas rapidly enlarge again after a GnRH agonist is stopped. The effects of these drugs on leiomyoma histopathology are unpredictable. Both hyaline degeneration and decreased vessel lumen size have been observed. Another treatment modality for symptomatic uterine leiomyomas is arterial embolization. Histopathologic evaluation of the effects of this treatment are obtained from leiomyomas expelled from the uterus after therapy or from hysterectomy specimens. The primary features are thrombosis, necrosis, and presence of embolic foreign material (Fig. 8-17). Acute features are coagulation necrosis and acute inflammation. Chronic features are hyaline necrosis and dystrophic calcification. Leiomyosarcoma
Figure 8-19 This uterine leiomyosarcoma has striking nuclear atypia and many mitotic figures. An atypical mitotic figure is present here (center left).
Leiomyosarcomas are encountered in the treatment of presumed leiomyomas in approximately 0.1% of cases. Leiomyosarcomas typically have tumor cell necrosis (Fig. 8-18), many mitoses (almost always >4 mitotic figures/10 high magnification fields [hpf] and usually ≥10/10 hpf), and nuclear atypia (Fig. 8-19). These histologic features are reflected grossly as soft, variegated tumors with necrosis (Fig. 8-20). Table 8-4 summarizes the principal predictors of malignancy.
FALLOPIAN TUBES Acute Salpingitis
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The tubal mucosa is arranged in longitudinal branching folds called plicae. The epithelium of the mucosa has three different cell types: secretory, ciliated, and “peg” cell (intercalated). Damage to the epithelium of the tube is associated with infertility and ectopic pregnancy. Acute salpingitis is an ascending infection that is usually associated with a sexually transmitted disease. The lumen contains pus (pyosalpinx) and may become distended. In chronic salpingitis there is a marked fibrosis of the tubal wall, usually associated with luminal dilatation as well as tubo-ovarian adhesions (Fig. 8-21).
Figure 8-20 Grossly, leiomyosarcomas have more variable coloration than seen with benign leiomyomas. This example has multiple pale yellow foci indicative of tumor cell necrosis.
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Chapter 8 Pathology of Reproductive Endocrine Disorders Table 8-4 Histologic Predictors of Malignancy Tumor cell necrosis Mitotic activity Nuclear atypia (pleomorphism and nuclear hyperchromatism)
Figure 8-23 A dilated, thin-walled uterine tube with agglutinated fimbria characterizes the gross pathology of hydrosalpinx.
Figure 8-21 Grossly, chronic salpingitis manifests with thickening and gray-white discoloration of the tubal wall. This is associated with edema in this example.
Figure 8-24 Hematosalpinx is the most consistent gross and microscopic feature of tubal pregnancy. In this example, chorionic villi are identified within the tubal lumen (center).
Figure 8-22 Xanthogranulomatis salpingitis has a mixed chronic inflammatory infiltrate dominated by foamy hystiocytes. Xanthogranulomatis inflammation results from tissue necrosis and obstruction. This pattern of inflammation is identical to that seen with malakoplakia except for the presence of Michaelis-Gutmann bodies in malakoplakia.
Xanthogranulomatous salpingitis is a histologic variant of chronic salpingitis resulting from necrosis and obstruction (Fig. 8-22). Hydrosalpinx is thought to be the result of end-stage salpingitis. Grossly, the tube is dilated and often thin-walled (Fig. 8-23). The lumen has a plasma transudate that is embryotoxic. Microscopically, the tubal wall is thin and fibrotic. A flattened epithelium lines the attenuated wall. However, scattered relatively normal-appearing tubal mucosal plicae usually remain.
the typical gross appearance. Trophoblastic tissue can grow predominantly intraluminally or invade the tubal wall (Fig. 8-24). Morphologically, trophoblasts and chorionic villi are usually visible at the implantation site. However, the diagnostic tissue (products of conception) may be confined to the intraluminal blood clot. Thus, the blood clot should be carefully examined in these cases. Ovarian ectopic pregnancies account for 3% of all ectopic gestations. An ectopic pregnancy found in the ovary is believed to be the result of an aborted tubal pregnancy in many cases. In 1878, Spiegelburg suggested four criteria to distinguish a primary ovarian pregnancy from a distal tubal pregnancy that has secondarily involved the ovary: (1) the fallopian tube with its fimbriae should be intact and separate from the ovary, (2) the gestational sac should occupy the normal position of the ovary, (3) the gestational sac should be connected to the uterus by the ovarian ligament, and (4) ovarian tissue must be present in the specimen attached to the gestational sac. Tuberculosis Salpingitis
Ectopic Pregnancy
Ectopic pregnancies can occur in several nonuterine locations. The most common site is the uterine tube. Hematosalpinx is
Tuberculosis can hematogeneously spread to the pelvic organs to cause chronic salpingitis. The majority of cases of tuberculosis of the uterine tubes simultaneously involve the endometrium.
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Figure 8-25 The microscopic appearance of streak gonads varies over time. Disorganized germ cells, sex cord cells, and stroma, seen initially, give way to a nonspecific fibrous stroma. In this example of a streak gonad removed from an adult, a focus of lutein cells (top center) is surrounded by nonspecific fibrous stroma.
Other uncommon causes of granulomatous tubal inflammation are sarcoidosis and Crohn’s disease.
Figure 8-26 This gonadoblastoma is dominated by masses of dystrophic calcium associated with fibrosis. The constituent germ cells and sex cord cells are inconspicuous. Gonadoblastomas are tumors composed of nests of germ cells associated with sex cord cells. Calcification is a consistent feature. Gonadoblastomas almost always arise in dysgenetic gonads associated with a karyotype containing Y chromosome material. Gonadoblastomas can give rise to invasive malignant germ cell tumors, usually dysgerminoma.
OVARIES Ovarian Cysts Functional Cysts
The most common cysts found in reproductive age women are functional cysts such as follicular or corpus luteum cysts. These cysts are most commonly lined with granulosa cells. Some functional cysts may cause disruption of the menstrual cycle or symptoms. However, most will spontaneously regress without surgical intervention. Occasionally a corpus luteum cyst may be confused grossly at the time of surgery with an endometriotic cyst. Microscopically, fibrosis and hemorrhage around the cyst can make it difficult to differentiate these cysts from endometriomas. Gonadal Dysgenesis
Patients with gonadal dysgenesis usually have streak gonads (Fig. 8-25). Dysgenetic gonad (i.e., abnormally developed gonads) can harbor gonadoblastoma (Fig. 8-26). Gonadoblastomas are mixed germ cell-sex cord stromal tumors characterized by nests of immature sex cord cells surrounding germ cells. Gonadoblastomas almost always affect dysgenetic gonads in patients with a karyotype containing Y chromosome. Importantly, gonadoblastomas can give rise to invasive germ cell neoplasms, most commonly dysgerminoma (Fig. 8-27). Patients with genotypes that include a Y chromosome are at risk to develop a gonadoblastoma. In these patients the gonad should be removed.
Figure 8-27 Delicate fibrous septa containing lymphocytes separate nests of germinoma cells in this characteristic example of an ovarian dysgerminoma.
settings, including normal single pregnancy. Grossly, the process is typically bilateral with greatly enlarged multicystic ovaries (Fig. 8-28). Pregnancy luteomas are non-neoplastic solid masses of lutein cells occurring in pregnant patients (Fig. 8-29).6 Multiple nodules occur in half of patients, and bilaterality occurs in at least one third of cases. The nodules spontaneously regress postpartum. Pregnancy luteomas are easily confused with sex cord neoplasms.
Pregnancy-related Cysts
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Pregnancy causes prominent luteinization of the theca layer of atretic follicles. Multiple atretic follicles with theca luteinization are designated theca-lutein cysts. Theca-lutein cysts result from high levels of or increased sensitivity to human chorionic gonadotropin. This condition has been called hyperreactio luteinalis. Multiple theca-lutein cysts often occur with hydatidiform mole and choriocarcinoma but occasionally in other clinical
Polycystic Ovaries
Polycystic ovary syndrome (PCOS) is an endocrine diagnosis rather than a pathologic one. The pathologic findings include characteristic gross and microscopic features. Grossly, the ovaries are referred to as sclerocystic (Fig. 8-30). Sclerocystic ovaries are enlarged with cysts underlying thickened fibrotic superficial stroma. Stigmata of prior ovulation are
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Figure 8-28 Cystic atretic follicles with luteinization of the theca characterize theca-lutein cysts. Theca-lutein cysts can result in massive cystic enlargement of the ovaries, as seen here. Theca-lutein cysts are associated with excessive levels of human chorionic gonadotropin. Therefore, typically, theca-lutein cysts are found with hydatidiform mole (in one third to one half of cases) and choriocarcinoma. However, theca-lutein cysts do occur with other gestations, including normal single pregnancies.
Figure 8-29 As illustrated here, pregnancy luteomas contain markedly luteinized cells having abundant, usually eosinophilic cytoplasm surrounding round nuclei with conspicuous nucleoli. A follicular space is identified (center).
inconspicuous or absent. The cysts are relatively small, usually ranging in size from 0.5 to 1.5 cm. Histologically, luteinized follicular cells line the cysts. Stromal Hyperthecosis
Stromal hyperthecosis is defined histologically as the presence of luteinized cells within the ovarian stroma. Stromal hyperthecosis can cause clinical signs of hyperandrogenism, and with peripheral conversion, hyperestrogenism. These patients are typically postmenopausal. Stromal hyperthecosis also occurs commonly in pregnancy. The ovaries are enlarged bilaterally with no clear appearance of cysts. Microscopically nests and individual lutein cells occur in the stroma (Fig. 8-31). The associated spindle cell ovarian stroma is typically hyperplastic, characterized by increased cellularity and a loss of the normal corticomedullary demarcation.
Figure 8-30 Sclerocystic ovaries result from chronic anovulation. Multiple cystic follicles underly thickened fibrotic superficial stroma. Note the absence of gross stigmata of prior ovulation, such as involuting corpora lutea.
Figure 8-31 The presence of luteinized cells within the ovarian stroma, as illustrated here, defines stromal hyperthecosis. The luteinized stromal cells have abundant cytoplasm that might stain eososinophilic or clear and vacuolated, as seen in this example. Stromal hyperthecosis commonly affects postmenopausal and pregnant patients and also causes a virilizing syndrome in younger nonpregnant patients.
Table 8-5 Types of Sex Cord-Stromal Tumors of the Ovary Granulosa-stromal cell tumors Granulosa cell tumors Tumors of the thecoma-fibroma group Sertoli-Leydig cell tumors: Androblastomas Steroid cell tumors Sex cord tumor with annular tubules Gynandroblastoma
Sex Cord-Stromal Tumors
Sex cord-stromal tumors represent approximately 5% of ovarian neoplasms. They are usually unilateral and occur in all age groups but are more common in postmenopausal women. Sex cord-stromal tumors often secrete hormones and are thus often associated with endocrine-related symptoms (Table 8-5). Both Leydig and
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Section 1 Basic Science Table 8-6 Typical Clinical Features of Sex Cord-Stromal Tumors Can occur in any age group May be hormonally active Usually unilateral Solid or cystic solid tumors
Figure 8-33 The pale angular grooved appearance of nuclei in adult-type granulosa cell tumors is the key diagnostic criterion.
Figure 8-32 This adult-type granulosa cell tumor has a characteristic hemorrhagic cystic and solid gross appearance.
theca cells secrete androgens (Table 8-6). They should be considered as part of the differential diagnosis of severely hyperandrogenic patients. However, many of these tumors have no endocrine manifestations. The stroma of the embryonic gonad has the potential to differentiate into cell types that have specific endocrine functions in both the male (Sertoli and Leydig cells) and the female (granulosa and theca cells) gonad. The Sertoli and granulosa cells both secrete inhibin, which can be used as a tumor marker for these patients. Elevated inhibin levels usually precede clinical recurrence of disease by months to years. Granulosa Cell Tumors
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Granulosa cell tumors are mostly found in postmenopausal women. The symptoms are related to estrogen secretion and can include postmenopausal bleeding with endometrial pathology such as endometrial hyperplasia or carcinoma. The tumors also occur in prepubertal girls and may produce precocious sexual development. In some cases, androgen secretion results in symptoms of hyperandrogenism. Granulosa cell tumors are usually unilateral and characteristically have both cystic and solid components (Fig. 8-32). Histologically, the tumor architecture varies, but the cells often have “coffee bean” nuclei described as pale, angular, and cleaved (Fig. 8-33).7 Granulosa cell tumors in prepubertal girls and young adults often have microscopic features differing from adult-type granulosa cell tumors. The differences are sufficient to permit recognition of these tumors as a distinctive subset with different behavior that is designated juvenile granulosa cell tumor.8,9
Figure 8-34 Ovarian thecomas often have a distinctive gross color, often yellowish tan, as seen in this example. Also note the homogeneous appearance and sharp circumscription.
Thecomas
Thecomas are usually unilateral (>90%) and typically occur in postmenopausal women. Thecomas may be hormonally active tumors. Grossly, thecomas typically are yellow and have a solid uniform appearance. Histologically, plump vacuolated spindle cells predominate (Fig. 8-34). Fibromas
Fibromas are usually unilateral tumors. Large fibromas (>6 cm) may be associated with ascites (40% of cases) or hydrothorax (Meigs’ syndrome). Other ovarian tumors may also cause these clinical signs (pseudo-Meigs’ syndrome). Fibromas are also associated with basal cell nevus syndrome (Gorlin’s syndrome).
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Figure 8-35 In contrast to the typical yellow color of a thecoma, ovarian fibromas, as illustrated here, typically have a pale tan gross appearance.
Fibromas have a uniform, pale, tan, solid gross appearance (Fig. 8-35) and benign spindle cells microscopically.
Figure 8-36 Sertoli-Leydig cell tumors have a broad spectrum of microscopic appearances resulting in part from variable mixtures of Sertoli tubules and nonspecific cellular stroma. In this example, well-formed Sertoli tubules arise in a background of densely cellular tissue.
well with survival (Fig. 8-36). Other hormonally active tumors occur that have lipid-laden cells associated with hyperandrogenism and are variably referred to as steroid cell tumors.
Sertoli-Leydig Cell Tumors
Sertoli-Leydig cell tumors are hormonally active tumors that occur in reproductive age women. These tumors are mostly unilateral. These tumors are classically associated with severe masculinization, with hirsutism, balding, clitoral hypertrophy, and voice changes. Sertoli-Leydig cell tumors have remarkably diverse histologic appearances.10 The fundamental components are a variable spindle cell stroma and variably immature tubules. Often, an alternating hypercellular and hypocellular zonation characterizes Sertoli-Leydig cell tumors. The presence of heterologous tissue contributes to the array of microscopic appearances. Histologic grading (well, intermediate, and poorly differentiated) correlates
PEARLS ●
●
●
●
●
A luteal phase endometrial biopsy lacks the accuracy required to make the diagnosis of luteal phase defect. Endometrial tuberculosis may be found on endometrial biopsy. Most common cysts found in reproductive age women are functional cysts. Sex cord-stromal tumors are more common in postmenopausal women. Fibromas can be associated with ascites or hydrothorax (Meigs’s syndrome).
REFERENCES 1. Noyes RW, Herrig AW, Rock J: Dating the endometrial biopsy. Fertil Steril 1:3–25, 1950. 2. Murray AJ, Meyer WR, Zaino RJ, et al: A critical analysis of the accuracy, reproducibility and clinical utility of histologic endometrial dating in fertile women. Fertil Steril 81:1333–1343, 2004. 3. Mostoufizadeh M, Scully RE: Malignant tumors arising in endometriosis. Obstet Gynecol 23:951–963, 1980. 4. Heaps JM, Neiberg RK, Berek JS: Malignant neoplasms arising in endometriosis. Obstet Gynecol 75:1023, 1990. 5. Jelovsek JE, Brainard J, Winans C, Falcone T: Endometriosis of the liver containing Müllerian adenosarcoma. Am J Obstet Gynecol 191:1725–1777, 2004.
6. Norris HJ, Taylor HB: Nodular theca-lutein hyperplasia of pregnancy (so-called “pregnancy luteoma”). Am J Clin Pathol 47:557–566, 1966. 7. Stenwig JT, Hazekamp JT, Beecham JB: Granulosa cell tumors of the ovary: A clinicopathological study of 118 cases with long-term follow-up. Gynecol Onco l7:136–152, 1979. 8. Young RH, Dickersin GR, Scullyl RF: Juvenile granulosa cell tumors of the ovary: A clinicopathologic analysis of 125 cases. Am J Surg Pathol 8: 575–596, 1984. 9. Biscotti DV, Hart WF: Juvenile granulosa cell tumors of the ovary. Arch Pathol Lab Med 113:40–46, 1989. 10. Young RH, Scully RE: Ovarian Sertoli-Leydig cell tumors: A clinicopathologic analysis of 207 cases. Am J Surg Pathol 9:543–569, 1985.
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9
Statistics for the Clinical Scientist Harry J. Khamis
INTRODUCTION Statistics is the science of (1) designing experiments or studies; (2) collecting, organizing, and summarizing data; (3) analyzing data; and (4) interpreting and communicating the results of the analyses. For medical research studies, the data often consist of measurements taken from human subjects (clinical studies) or from animals. The essential goal of statistics is to make conclusions (or inferences) about a parameter, such as a mean, proportion, regression coefficient, or correlation. The true value of the parameter can be determined by obtaining the measurements of the entire population to which inferences are to be made. However, this is most often impractical or impossible to do. So, instead we take a subset of the population, called a sample. Then we analyze the sample to estimate or test the parameter value. As an example, suppose we would like to know the mean fetal humeral soft tissue thickness (HSTT) of singleton gestations for women at 20 weeks’ gestation. It would be impractical to (sonographically) measure the fetal HSTT for all such women, so we randomly sample, say, 50 such women. We then estimate the mean fetal HSTT from these 50 women. The mean fetal HSTT from these 50 women (called the sample mean) will undoubtedly not be the same as the (theoretical) mean that we would have obtained had we measured all such women (called the population mean), but it should be “close.” How close is it? Would it be closer if we had randomly sampled 100 women? 500 women? These are the questions that the science of statistics is designed to answer. The next section outlines two essential characteristics of variables. The remaining sections of this chapter present the basic statistical methods used to accomplish the four goals of statistics defined above.
LEVEL OF MEASUREMENT AND VARIABLE STRUCTURE Any medical research study consists of a set of variables, such as gestational age, birth weight, body mass index (BMI), gender, Bishop score, blood pressure (BP), cholesterol level, severity of disease, dosage level, type of treatment, or type of operation. For statistical purposes, it is important to characterize each variable in two ways: (1) level of measurement and (2) variable structure.
Level of Measurement The level of measurement (or measurement scale) of a variable is its designation as continuous or discrete. A continuous variable has
values taken, at least theoretically, from a continuum of the real number line. Examples are gestational age, BP, and BMI. A discrete variable has discrete values (i.e., values not coming from a continuum of the real number line). Examples are gender (male, female), severity of disease (low, medium, high), and type of operation (standard, modified, laparoscopic). The “severity of disease” variable is called an ordinal discrete variable because there is an order associated with its levels; the “type of operation” variable is called a nominal discrete variable because there is no order associated with its levels.
Variable Structure A dependent variable (also called outcome, endpoint, or response variable) is the primary variable of a research study. It is the behavior of such a variable that is of primary concern, including the effects (or influence) of other variables on it. An independent variable (also called explanatory, regressor, or predictor variable) is the variable whose effect on the dependent variable is being studied. Designation of which variables are dependent and which are independent in a research study establishes the variable structure. How a variable is handled statistically depends in large part on its level of measurement and its variable structure.1
EXPERIMENTAL/RESEARCH DESIGN The three core principles of experimental design are (1) randomization, (2) replication, and (3) control or blocking. Random selection of subjects from the study population or random assignment of subjects to treatment groups is necessary to avoid bias in the results. A random sample of size n from a population is a sample whose likelihood of having been selected is the same as any other sample of size n. Such a sample is said to be representative of the population. See any standard statistics text for a discussion of how to randomize.2,3 Replication refers to the measurement of subjects under the same condition. This is necessary to determine how the measurements vary for that condition. So, the measurements of several subjects receiving the same treatment would be considered replications. Control, or blocking, is a technique to adjust an analysis for another variable (sometimes called a confounding variable or covariate). The variability associated with such a variable is accounted for in the analysis in a way that increases the precision of the comparisons of interest. See the discussion of the randomized complete block design for an example.
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Section 1 Basic Science Completely Randomized Design (CRD) In the CRD, subjects are randomly assigned to experimental groups. As an example, suppose that the thickness of the endometrium is observed via ultrasound for women randomly assigned to three different fertility treatments (treatments T1, T2, and T3). Twenty-seven subjects are available for study, so 9 subjects are randomly selected to receive treatment T1, 9 are randomly selected from the remaining 18 to receive treatment T2, and the remaining 9 receive treatment T3. The data layout appears in Table 9-1. In addition to randomness, an important assumption of the CRD is that the samples are independent (i.e., the outcome measurement—in this case, endometrial thickness—for one subject is not related to that of any other subject). For instance, two related subjects (e.g., sisters) should not both be included in the data set because they are genetically related and hence their endometrial thicknesses may be correlated. The principles of the CRD are the same for a survey, where subjects form groups in a natural way. For instance, in comparing the mean cholesterol level among first-, second-, and thirdtrimester pregnant women, a random sample of all pregnant women can be obtained, and then each woman can be naturally classified as being in the first, second, or third trimester. In this case, the sample size for each group will likely not be the same. Alternatively, random samples of 10 first-trimester, 10 secondtrimester, and 10 third-trimester women can be obtained (stratified sampling). Note in these examples that the principles of randomization and replication are used. The following design is used for controlling or blocking.
ethnic group E1 and randomly assign 3 to each of the three treatments; likewise for ethnic groups E2 and E3, for a total of 27 subjects. The data layout would appear as in Table 9-2.
Latin Square Design (LSD) To control for a second factor, a Latin square design is used. For example, the subjects in the endometrial thickness study come from three different age groups, A1, A2, and A3. Because the endometrial thickness variable is likely to be more homogeneous for subjects from a given age group than for subjects from two different age groups, we should block on the age group in addition to the ethnic group.
Repeated Measures Design If in the RCBD the blocking factor is the subject, and the same subject is measured repeatedly, then the design becomes a repeated measures design. For instance, suppose that each of 10 subjects receives three different BP medications at different time points. For each medication, the BP is measured 5 days after the medication is started, then there is a 2-week “wash-out period” before starting the next medication. Also, the order of the medications is randomized. The data layout appears as in Table 9-3. Many more sophisticated and complex experimental designs exist, and can be found in any standard text on experimental design.4,5 For evaluating the validity, importance, and relevance of clinical trial results, see the article by The Practice Committee of the American Society for Reproductive Medicine.6 For surveys, there are many ways in which the sampling can be carried out Table 9-2 Data Layout For a Randomized Complete Block Design
Randomized Complete Block Design (RCBD) The RCBD is a generalization of the CRD whereby a second factor is included in the design so that the comparison of the levels of the treatment factor can be adjusted for its effects. For example, in the endometrial thickness study, there may be three different ethnic groups of women, E1, E2, and E3, included in the study. Because the variation of the endometrial thicknesses may be higher between two different ethnic groups than within a given ethnic group, it would be wise to block on the ethnic group factor. In this case, we would randomly select 9 subjects from
Treatment
Ethnic Group
T1
T2
T3
E1
x x x
x x x
x x x
E2
x x x
x x x
x x x
E3
x x x
x x x
x x x
Table 9-1 Data Layout For a Completely Randomized Design Table 9-3 Data Layout For a Repeated Measures Design
Treatment
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Replication
T1
T2
T3
1
x*
x
x
2
x
x
x
3
x
x
x
.
.
.
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.
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9
x
x
x
*“x” represents a measurement for a given subject.
Treatment Subject
T1
T2
T3
1
x
x
x
2
x
x
x
3
x
x
x
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10
x
x
x
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Chapter 9 Statistics for the Clinical Scientist (e.g., simple random sampling, stratified random sampling, cluster sampling, systematic sampling, or sequential sampling).7,8
DESCRIPTIVE STATISTICAL METHODS After the survey has been taken, the study has been carried out, or the experiment has been performed, then the data are obtained and entered into a spreadsheet or other usable form. After the data entry and data error checking have been completed, the first statistical analyses are performed; these are most often descriptive analyses—organizing and summarizing the data in the sample. Many different statistical methods are used to help organize and summarize the data. The descriptive statistical methods used for continuous variables differ from those used for discrete variables.
Continuous Variables The principal descriptive features of continuous variables are (1) central location and (2) variability (or dispersion). An important numerical measure of the centrality of a continuous variable is the mean: n
x– = –1 Σ xi n i=1 where n = number of observations and xi = ith measurement in the sample. Alternative measures of centrality are the median (middle measurement, or average of the two middle measurements if n is even, in the list of measurements rank-ordered from smallest to largest) and the mode (most frequent measurement). A simple numerical measure of the variability or dispersion of a continuous variable is the range: the largest measurement minus the smallest measurement. The larger the variability in the measurements, the larger the range will be. A more common numerical measure of variability is the variance: n s2 = —1 — ∑ (xi−x–)2 n−1 i=1
Note that the variance is approximately the average of the squared deviations (or distances) between each measurement and its mean. The more dispersed the measurements are, the larger s2 is. Because s2 is measured in the square of the units of the actual measurements, sometimes the standard deviation is used as the preferred measure of variability: s = √s2 Also of interest for a continuous variable is its distribution (i.e., a representation of the frequency of each measurement or intervals of measurements). There are many forms for the graphical display of the distribution of a continuous variable, such as a stem-and-leaf plot, boxplot, or bar chart. From such a display, the central location, dispersion, and indication of “rare” measurements (low frequency) and “common” measurements (high frequency) can be identified visually.2 It is often of interest to know if two continuous variables are linearly related to one another. The Pearson correlation coefficient, r, is used to determine this. The values of r range from –1 to +1.
If r is close to –1, then the two variables have a strong negative correlation (i.e., as the value of one variable goes up, the value of the other tends to go down [consider “number of years in practice after residency” and “risk of errors in surgery”]). If r is close to +1, then the two variables are positively correlated (e.g., “fetal humeral soft tissue thickness” and “gestational age”). If r is close to zero, then the two variables are not linearly related. One set of guidelines for interpreting r in medical studies is: |r| > 0.5 ⇒ “strong linear relationship,” 0.3 < |r| ≤ 0.5 ⇒ “moderate linear relationship,” 0.1 < |r| ≤ 0.3 ⇒ “weak linear relationship,” and |r| ≤ 0.1 ⇒ “no linear relationship”.9,10
Discrete Variables For summarization of a discrete variable, a frequency table is used: for each discrete value of the variable, its frequency (how many times it occurs in the sample of, say, n observations) and relative frequency (frequency/n) are recorded. Of course, the sum of the frequencies over all of the discrete levels of the variable must be n, and the sum of the relative frequencies must be 1.0 (100%). For two discrete variables the data are summarized in a contingency table. A two-way contingency table is a cross-classification of subjects according to the levels of each of the two discrete variables. An example of a contingency table is given in Table 9-4. Here, there are a + b + c + d subjects in the sample; there are “a” subjects under the standard treatment who died, “b” subjects under the standard treatment who survived, and so on. If it is desired to know if two discrete variables are associated with one another, then a measure of association must be used. Which measure of association would be appropriate for a given situation depends on whether the variables are nominal or ordinal or a mixture.11,12 In medical research, two of the important measures that characterize the relationship between two discrete variables are the risk ratio and the odds ratio. The risk of an event, p, is simply the probability or likelihood that the event occurs. The odds of an event is defined as p/(1–p) and is an alternative measure of how often an event occurs. The risk ratio (sometimes called relative risk) and odds ratio are simply ratios of the risks and odds, respectively, of an event for two different conditions. In terms of the contingency table given in Table 9-4, these terms are defined as follows. Term
Definition
risk of death for those on the standard treatment
a/(a+b)
risk of death for those on the new treatment
c/(c+d)
odds of death for those on the standard treatment
a/b
odds of death for those on the new treatment
c/d
risk ratio of death
a(c+d)/c(a+b)
odds ratio of death
ad/bc
Note that a risk ratio of 4.0 means that the risk of death under the standard treatment is four times that under the new treatment. An odds ratio of 4.0 means that the odds of death are four times higher under the standard treatment than under the new treatment. Another important measure in clinical practice is the risk difference, RD, the absolute difference between the risk of death under the standard treatment and the risk of death under the new treatment:
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Section 1 Basic Science Table 9-4 Contingency Table for the Cross-classification of Subjects According to Treatment and Outcome. Outcome
Treatment
Definition
Interpretation
prevalence rate
(a+c)/ (a+b+c+d)
proportion of the sample that is truly positive
sensitivity
a/(a+c)
proportion of true positives who test positive with the experimental procedure
Died
Survived
Total
specificity
d/(b+d)
proportion of true negatives who test negative with the experimental procedure
positive predictive value
a/(a+b)
proportion of those testing positive with experimental procedure who are truly positive
negative predictive value
d/(c+d)
proportion of those testing negative with experimental procedure who are truly negative
false positives
b
number of subjects who are negative but test positive
false negatives
c
number of subjects who are positive but test negative
Standard
a
b
a+b
New
c
d
c+d
Total
a+c
b+d
RD =
Term
| a +a b – c +c d |
The inverse of the risk difference is the number needed to treat, NNT: NNT =
1 RD
Table 9-5 Contingency Table for Diagnostic Test Evaluation
NNT is an estimate of how many subjects would need to receive the new treatment before there would be one more or less death, as compared to the standard treatment. For example, in a study by Marcoux and colleagues13 341 women with endometriosis-associated subfertility were randomized into two groups, laparoscopic ablation and laparoscopy alone. The study outcome was “pregnancy > 20 weeks’ gestation.” Of the 172 women in the first group, 50 became pregnant; of the 169 women in the second group, 29 became pregnant (a = 50, b = 122, c = 29, and d = 140). The risk of pregnancy is 0.291 in the first group and 0.172 in the second group; the corresponding odds of pregnancy are 0.410 and 0.207. The risk ratio is 1.69 and the odds ratio is 1.98. The likelihood of pregnancy is 69% higher after ablation than after laparoscopy alone; the odds of pregnancy are about doubled after ablation compared to laparoscopy alone. The risk difference is RD = 0.291 − 0.172 = 0.119
Results of Gold Standard + Results of experimental procedure
Total
–
Total
+
a
b
a+b
–
c
d
c+d
a+c
b+d
Use of these measures provides insight into the effectiveness of a new, experimental procedure relative to the Gold Standard.14–16 To select that cutoff point for the experimental procedure that defines a “+” or “–” result in such a way that sensitivity and specificity are optimized, Receiver Operating Characteristic (ROC) curves are used.17 The ROC curve is a plot of the sensitivity of test (Y-axis) versus the false positive rate (X-axis; 1-specificity). This measure is used to assess how well a test can identify patients with a disease. An area under the curve of 1 is a perfect test and 0.5 is a useless test.
and number needed to treat is
ESTIMATION 1 NNT = = 8.4 0.119 Rounding upward, approximately 9 women must undergo ablation to achieve 1 additional pregnancy.
DIAGNOSTIC TEST EVALUATION
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A specialized contingency table is formed when one factor represents the results of an accurate, standard test (sometimes called the Gold Standard), and the other factor represents the results of a new, perhaps less invasive, experimental procedure. This contingency table, used for diagnostic test evaluation, is given in Table 9-5. Several different measures are used to assess the effectiveness of the experimental procedure relative to the Gold Standard; they are defined and interpreted below.
Generally, there are two ways in which inferences can be made to a population of interest: (1) estimate population parameters or (2) test hypotheses about population parameters. A point estimate of a parameter, calculated from a random sample of the population, is the best single estimated value of the parameter. If a random sample of 50 fetuses at 20 weeks’ gestation are each measured sonographically for fetal HSTT, and the average of these 50 values is 9.7 mm, then our point estimate of the true mean fetal HSTT (i.e., the mean fetal HSTT of all such fetuses) is 9.7 mm.
Confidence Intervals Although the point estimate is expected to be “close” to the parameter value, we are often interested in how close it is. Therefore, many researchers prefer to use a confidence interval
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Chapter 9 Statistics for the Clinical Scientist to estimate the parameter. A confidence interval is an interval for which the endpoints are determined by statistics calculated from the sample; for this interval there is a high probability (usually set at 95%) that it contains the population parameter value. For most applications, the point estimate is at the midpoint of the confidence interval. In the example above, if the 95% confidence interval for the mean fetal HSTT is [7.2, 12.2], then we say that we are 95% confident that the true mean fetal HSTT falls between 7.2 mm and 12.2 mm. This interval can also be written as 9.7 mm ± 2.5 mm. The value 2.5 is called the margin of error; it represents the range of values on either side of the point estimate, 9.7 mm, that are regarded as “plausible” values of the true mean fetal HSTT. Values farther than 2.5 mm away from the point estimate are regarded as “implausible” values. In this way, the confidence interval, with its margin of error, provides a measure of the reliability of the point estimate. Confidence intervals that have a small width ( i.e., small margin of error) are desirable because the true value is then estimated reliably, or within a small range of values. One way to reduce the width of a confidence interval is to increase the sample size. For example, the formula for the 95% confidence interval of a population mean is s x– ± (1.96) ––– –– √n This particular formula is valid for relatively large samples, say n ≥30. Note that the margin of error is s (1.96) ––– – √n which decreases when n increases. The basic formula for most confidence intervals is point estimator ± (reliability coefficient)(standard error) where the reliability coefficient is a percentile taken from an appropriate distribution, and the standard error is the standard deviation of the estimator. In the confidence interval for a population mean given above, the point estimator is the sample mean, –– X the reliability coefficient is the 97.5th percentile from the standard normal distribution, and the standard error is s ––– –– n √ Refer to any standard statistics text to obtain confidence interval formulas for population parameters (e.g., McClave and Sincich2).
TESTS OF HYPOTHESES For statistical purposes, research questions are framed in terms of two hypotheses. The null hypothesis, H0, is typically the hypothesis of “no change,” or “no difference,” or the status quo, and is stated in terms of parameters. The alternative hypothesis, also called the research hypothesis, HA, is typically the hypothesis of “change” and is the complement of H0. For example, consider the research hypothesis: “the mean fetal HSTT at 20 weeks’ gestation is less than 10 mm.” The hypotheses would be written formally as:
H0: μ ≥ 10 versus HA: μ < 10 where μ = mean fetal HSTT.
P-Value A statistical test of hypothesis is a procedure whereby a determination is made as to whether there is sufficiently strong evidence in the data to support the research hypothesis, HA. If so, then H0 is “rejected”; otherwise H0 is “not rejected.” How is this determination made? A quantity called the P-value (P) is calculated from the data. The P-value is actually a probability and hence lies between zero and one. Small values of P correspond to a rejection of H0. In this case, the test result is said to be “statistically significant.” How small does P have to be to lead to a rejection of H0? Most researchers use a cutoff (called the level of significance of the test) of 0.05. That is, if P < 0.05, then H0 is rejected, and one can conclude that there is strong evidence in the data to support the research hypothesis, HA, at the 0.05 level of significance. When P ≥ 0.05, then H0 is not rejected and one concludes that there is not sufficient evidence in the data to support the research hypothesis. For most research studies, the P-value for a given result is simply reported, leaving the reader to make his/her own conclusion about the strength of evidence in the data supporting the research hypothesis. The P-value represents the probability of obtaining the sample that was observed “by chance alone” (i.e., the probability of obtaining a sample at least as contradictory to H0 as the one observed when H0 is assumed to be true). So, if P is very small, then it implies that the observed sample is very rare if H0 is really true, leading to the conclusion that H0 must not be true. If one test has P = 0.10 and a second test has P = 0.01, then the evidence against H0 is 10 times stronger in the second test than in the first test in the sense that the probability of obtaining a sample at least as contradictory to H0 as the observed sample is 10 times higher in the first test than in the second test. That is, the sample in the first test is not as extreme when H0 is true as the sample in the second test.
Type I and II Errors, Statistical Power When making the decision about whether the evidence in the data is strong enough to reject H0, the only two possible outcomes are (1) reject H0 or (2) fail to reject H0. In this decisionmaking process, there are only two possible errors that can be made: (1) incorrectly reject H0 (i.e., reject H0 even though H0 is true), or (2) incorrectly fail to reject H0 (i.e, fail to reject H0 even though H0 is false). The first error is called the type I error and its probability of occurring is denoted by alpha (α). The second error is called the type II error and its probability of occurring is denoted by beta (β). In practice we would like both α and β to be small. The statistical test that is used to make the decision about rejecting or failing to reject H0 is designed to ensure that α is no larger than the level of significance chosen by the researcher (again, 0.05 is the most common choice for the level of significance). Hence, when testing a set of hypotheses one can be confident that the likelihood of incorrectly rejecting H0 is at most, say, 0.05. The type II error rate, β, is controlled by, among other things, the sample size, n. That is, the larger n is, the lower β is.
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Section 1 Basic Science Statistical power is defined as 1 – β , which is the probability of correctly rejecting H0 (i.e., rejecting H0 when H0 is really false). In practice, we would like the statistical power to be high (at least 0.8) for those alternatives (i.e., values of the parameter in HA) that are deemed to be clinically important. As indicated above, β decreases as n increases, and hence power increases with n.
STATISTICAL PROCEDURES Comparison of Means When the means of k ≥ 2 populations are compared, then the one-way analysis of variance (ANOVA) is used for the analysis; it is based on k-independent samples and the corresponding design is the CRD. The hypotheses being tested are: H0: μ1 = μ2 = . . . = μk versus HA: at least one mean differs from the others For example, one may be interested in comparing the mean fetal HSTT among four ethnic groups of women: white, AfricanAmerican, Asian, and “other.” If H0 is rejected (e.g., P < 0.05), then it is concluded that the mean fetal HSTT is not the same for all four ethnic groups. The determination of how the four means differ from one another is made through a multiple comparisons procedure. There are many such procedures, but the recommended ones are Tukey’s HSD (“honestly significant difference”) post hoc test, the Bonferroni-Dunn post hoc test, or the Neuman-Keuls test.18 In the special case of the ANOVA in which k = 2, so that the means of two populations are compared based on two independent samples, the statistical test is called the two-sample (or pooled-sample) t-test. If the k samples are not independent, but rather matched (i.e., correlated), then an ANOVA based on the RCBD is conducted. In the special case where k = 2, so that the means of two populations are compared based on paired samples, then the statistical test is called the paired t-test. For instance, if the fetal HSTT for each of n subjects is measured at 20 weeks’ gestation and again at 30 weeks’ gestation, then the two observations are correlated because they come from the same subject. In this case, the P-value is based on the paired differences of the two measurements. If we wish to test that the mean fetal HSTT is higher at 30 weeks than at 20 weeks, the hypotheses would be written H0: μ30 weeks ≤ μ20 weeks
142
versus
HA: μ30 weeks > μ20 weeks,
where μ represents the mean fetal HSTT. What is an appropriate sample size to use for a two-sample t-test or a paired t-test? If the two populations have comparable standard deviations, then a sample of size at least n = (16)(sc/δ)2 for each group will ensure 80% power for the two-sample t-test conducted at the 0.05 level of significance, where sc is the estimate of the common standard deviation of the two samples, and δ is a mean difference that is deemed to be clinically important.19 For a paired-sample t-test, a sample of size at least n = (8)(sd/δ)2 pairs will ensure 80% power for a 0.05 level test, where sd is the standard deviation of the differences of the paired measurements.19
If means are compared among the levels of each of two factors, then a two-way ANOVA is conducted. Consider comparing the mean fetal HSTT between two age groups and among four ethnic groups of pregnant women. In addition to the two effects, age and ethnic group, there is a third effect to consider— the statistical interaction between age and ethnic group. A twofactor statistical interaction exists if, for instance, the difference in mean fetal HSTT between “young” and “old” pregnant women is not the same for every ethnic group. For example, AfricanAmerican young and old women may have fetuses that differ widely in mean HSTT, whereas Asian young and old women may have fetuses with comparable mean HSTT levels. In general, a design with N factors is analyzed using an N-way ANOVA, where 2-factor interactions, 3-factor interactions, …, and the N-factor interaction may be analyzed.
STUDYING RELATIONSHIPS/PREDICTION Often in medical research one is interested in studying the effects of a set of independent variables, X1, X2, …, Xk, on a continuous dependent variable, Y. Alternatively, one may be interested in predicting Y from a set of predictor variables. This can be done using a multiple regression analysis. Such an analysis models the mean, or expected, Y value, E(Y), on a multiple linear function of the independent (or predictor) variables: E(Y) = β 0 + β 1x1 + β 2x2 + . . . + βkxk A major result of the multiple regression analysis is the estimation of the regression coefficients βi = 1, 2, …, k, and the statistical test of significance for each coefficient. The hypotheses being tested are: H0: βi = 0
versus
HA: βi ≠ 0
for i = 1, 2, …, k. A regression coefficient βi is interpreted as the amount by which E(Y) changes for a unit increase in xi while all other predictor variables are held constant. Suppose we regress a pregnant woman’s body temperature on (1) number of days gestation, (2) age, (3) ethnic group (where 1=white and 0=other), and (4) BMI. Notationally, we would write E (temperature) = β0 + β1 (#days) + β 2 (age) + β 3 (ethnic) + β4 (BMI) There are two cautionary notes concerning the predictor variables in any regression model, including logistic and Cox regression models: (1) Each predictor variable is only allowed to be continuous or binary. If a predictor variable is discrete with k > 2 levels, then k – 1 “dummy” or “indicator” variables must be formed to represent the k-level discrete variable in the regression equation. (2) The predictor variables in a regression model should not be highly correlated with each other. For instance, a correlation coefficient between any two predictors exceeding 0.8 or 0.9 in absolute value would lead to a condition called multicollinearity, which leads to severe instability of the
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Chapter 9 Statistics for the Clinical Scientist estimated regression coefficients. See any standard regression text for further discussion of these two points.20–23 What is an appropriate sample size for a multiple regression? In general, a sample size of at least n = 10k should be used,22 where k is the number of predictors in the model. However, this guarantees nothing about the statistical power. To ensure 80% power of detecting a “medium” size effect, the sample size should be at least n = 50 + 8k.24
logit(recurrence) = 1.2 + (0.8)*X1 + (1.3)*X2 + (0.3)*X3 – (2.5)*X4 Each of the coefficients is statistically significant at the 0.05 level of significance. The results of the analysis are given below.
Regressor
Estimated Coefficient
Odds Ratio
X1
0.8
2.2
For each additional year between the two deliveries, the odds of recurrence increase by a factor of 2.2.
X2
1.3
3.7
The odds of recurrence are higher for those who received an episiotomy in the second delivery by a factor of 3.7.
X3
0.3
1.3
For each additional unit of increase in weight of the second infant over the first infant, the odds of recurrence increase by 30%.
X4
–2.5
0.08
The odds of recurrence for women who received analgesics during the second labor are 92% lower than for those who did not receive analgesics during the second labor.
COMPARING PROPORTIONS Consider the comparison of two population proportions, H0: p1 = p2
versus
HA: p1 ≠ p2.
As an example, suppose we wish to compare the proportion of neonates with fetal growth restriction (FGR) between urban and rural first-time mothers. H0: purban = prural
versus
HA: purban ≠ prural
Suppose that in samples of 100 urban and 100 rural first-time mothers, 12 urban mothers and 15 rural mothers had babies with FGR. For these data, the P-value associated with the above hypotheses is P = 0.535; there is not strong evidence that the two proportions are different. As a generalization, consider the regression of a discrete variable on a set of predictor variables. The logistic regression equation is used in this case; if p represents a probability of interest (e.g., probability of FGR), then the logistic regression equation is: log( p/(1−p)) = β 0 + β 1x 1 + β 2x 2 + . . . + β k x k The quantity p/(1–p) is the odds of the event of interest (i.e., occurrence of FGR), and the left side of the equation, log(p/(1–p)), is called the logit of the event of interest. So, βi represents the amount by which the logit changes for a unit increase in xi, and eβi respresents the odds ratio (i.e., the ratio of the odds of the event of interest associated with a unit increase in xi). As an example, an obstetrics and gynecology resident from the Wright State University School of Medicine wished to identify the predictors of the recurrence of third- and fourthdegree obstetrical lacerations for women who had given birth to two children. A retrospective chart review of vaginal births at Miami Valley Hospital in Dayton, Ohio was conducted. The outcome is “recurrence of third- and fourth-degree obstetrical lacerations” (coding: 0=No, 1=Yes), and the predictors were: X1 = number of years between the two deliveries, X2 = whether an episiotomy was performed in the second delivery (coding: 0=No, 1=Yes), X3 = birthweight of second infant minus birthweight of first infant, and X4 = whether analgesics were received during the second labor (coding: 0=No, 1=Yes). The data were analyzed by the Wright State University Statistical Consulting Center. The logit of recurrence of third- and fourth-degree obstetrical lacerations was regressed on the four predictors for a sample of 1852 women. The estimated model is:
Interpretation
What is an appropriate sample size for a logistic regression? Consider a binary outcome variable. In general, the number of subjects falling into the smaller of the two outcome levels should be at least 10k, where k = number of predictor variables in the logistic regression equation.25-27 To ensure a specified power, a sample size software or a table28 must be used.
COMPARING SURVIVAL RATES In survival studies, one is typically interested in the occurrence of a particular event over time (e.g., death). It is common to observe subjects from a well-defined starting point and to establish an ending time of the study, which may be days, or weeks, or …, years later. During this follow-up period, one of three things will happen for a given subject: (1) the event of interest will occur before the end of follow-up, (2) the subject will fall out of the study (e.g., move away, die from a cause having nothing to do with the event under study, or refuse to participate in the study any further), or (3) the subject is observed through the entire follow-up period without experiencing the event of interest. In the latter two cases, the observations are said to be censored (i.e., incomplete information is available for these subjects). For instance, in the case of death, all that is known about the subject who survives the entire follow-up period without dying is that he or she dies at some time after the end of follow-up. In the former case, complete information is available (i.e., the “survival” time until the event occurs is known), so the observation is not censored. Two important quantities for evaluating survival data are (1) the survival function and (2) the hazard function. The survival function, S(t), is the probability that a subject experiences the event of interest after time t; S(t) = P[X>t], where X represents the time until the event of interest occurs. The estimated values of S(t) plotted against t are called KaplanMeier curves.29
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Section 1 Basic Science The hazard function is, mathematically, d(ln(S(t)) h(t) = − ––––––––– dt Practically, it is interpreted as the average number of times the event of interest occurs in one unit of time at time t. If the event of interest is, say, death, then an increasing hazard function corresponds to an increased death rate. The hazard ratio is the ratio of two hazard functions. The standard statistical model for analyzing survival data is the Cox proportional hazards regression model.30 In this model the hazard rate is regressed on a set of regressor variables, h(t) = h0(t)e
β 0 + β 1x1 + β 2x2 + . . . + β kxk
where h0(t) is an arbitrary baseline hazard rate. This model is used to study the effects of the regressor variables on the hazard function. Suppose that 1000 new mothers are monitored from delivery to the baby’s first unscheduled hospital visit. The study period lasts 2 years, and new deliveries are enrolled during the first year. The hazard function (for baby’s first unscheduled hospital visit) is regressed on mother’s age, mother’s BMI, and whether the mother delivered by cesarean section (coding: 1=Yes, 2=No). In the table below, the results are presented along with the interpretation. Assume that all of the β-coefficients are statistically significant.
Term
Estimated Coefficient
Hazard Ratio
Proper study design and proper analysis of data are crucial for arriving at correct, supportable conclusions concerning any research endeavor involving data. Medical research has become increasingly complex and multidisciplinary. Simple t-tests or chisquared tests are rarely sufficient to fully address the multidimensional, complicated research questions that are currently investigated. For this reason, statistical scientists have endeavored to keep up with the vast data sets having complex data structures and intricate designs that arise in medical research.
PEARLS ●
●
●
●
Interpretation
Age
1.5
4.5
For each additional year in Age, the risk of an unscheduled visit increases by a factor of 4.5
BMI
1.1
3.0
For each additional unit in BMI, the risk of an unscheduled visit triples
–1.4
0.25
The risk of an unscheduled visit for those who did not have a Cesarian section is one fourth of those who did have a Cesarian section
Cesarian section
CONCLUSION
What is the appropriate sample size for a Cox regression? In general, the number of events (i.e., uncensored observations) in the sample should be at least 10k, where k = number of predictors in the Cox regression model.31 Van Belle27 recommends that the sample size should be n = 16/(ln(h))2 per group, where h is a hazard ratio that is deemed to be clinically important.
●
The proper form of analysis for a given data set is inextricably linked to the experimental design. Therefore, careful thought should be devoted to the design phase of the study. Statistical significance is not necessarily the same as clinical or practical significance. If the sample size is inordinately large, then statistical significance will be achieved even for small, meaningless effects.10,32,33 Failure to achieve statistical significance does not necessarily mean that there is not an important effect. Possible alternative explanations for a statistically nonsignificant result are that (1) the sample size was not large enough to ensure adequate statistical power (i.e., a type II error is committed), (2) one or more study variables are not sufficiently reliable, or (3) there are deficiencies in the study design. Every statistical model has underlying assumptions that must be at least approximately satisfied by the data for the results of the analysis to be valid. Violation of one or more model assumptions by the data may result in misleading conclusions.34 It is crucial that the data be diagnosed for violations of model assumptions. If there is clear evidence of such violations then remedial actions must be taken (e.g., transformations of certain variables or use of alternative methodologies such as nonparametric statistical methods).22,35,36 Consult an applied statistician or biostatistician throughout the research project, starting at the design phase. Inclusion of such a person on your research team will ensure that any conclusions will be clearly and strongly supported by the data in a documented way.
REFERENCES
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1. Khamis HJ: Deciding on the correct statistical technique. J Diagn Med Sonogr 8:193–198, 1992. 2. McClave JT, Sincich T: Statistics, 8th ed. Upper Saddle River, N.J., Prentice-Hall, 2000. 3. Zar JH: Biostatistical Analysis, 3rd ed. Upper Saddle River, N.J., Prentice-Hall, 1996. 4. Hicks CR: Fundamental Concepts in the Design of Experiments, 4th ed. New York, Saunders College Publishing, 1993. 5. Montgomery DC: Design and Analysis of Experiments, 5th ed. New York, John Wiley & Sons, 2001.
6. The Practice Committee of the American Society for Reproductive Medicine: Interpretation of clinical trial results. Fertil Steril 81:1174–1180, 2004. 7. Thompson S: Sampling, 2nd ed. New York, John Wiley & Sons, 2002. 8. Tryfos P: Sampling Methods for Applied Research. New York, John Wiley & Sons, 1996. 9. Burns N, Grove SK: The Practice of Nursing Research, 4th ed. Philadelphia, W.B. Saunders, 2001. 10. Cohen J: Statistical Power Analysis for the Behavioral Sciences, 2nd ed. Mahwah, N.J., Lawrence Erlbaum Associates, 1988.
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Chapter 9 Statistics for the Clinical Scientist 11. Goodman LA, Kruskal WH: Measures of Association for Cross Classifications. New York, Springer-Verlag, 1979. 12. Khamis HJ: Measures of association. In Armitage P, Colton T (eds): Encyclopedia of Biostatistics, 2nd ed. New York, John Wiley & Sons, 2004. 13. Marcoux S, Maheux R, Berube S: Laparoscopic surgery in infertile women with minimal or mild endometriosis, Canadian Collaborative Group on Endometriosis. NEJM 337:217–222, 1997. 14. Khamis HJ: Statistics refresher: Tests of hypothesis and diagnostic test evaluation. J Diagn Med Sonogr 3:123–129, 1987. 15. Khamis HJ: An application of Bayes’ rule to diagnostic test evaluation. J Diagn Med Sonogr 6:212–218, 1990. 16. Riegelman RK: Studying a Study and Testing a Test: How to Read the Medical Literature. Boston, Little, Brown and Company, 1981. 17. Metz CE: Basic principles of ROC analysis. Semin Nuclear Med 8:283–298, 1978. 18. Hsu JC: Multiple Comparisons, Theory and Methods. New York, Chapman & Hall, 1996. 19. Lehr R: Sixteen s-squared over d-squared: A relation for crude sample size estimates. Statistics Med 11:1099–1102, 1992. 20. Draper NR, Smith H: Applied Regression Analysis, 2nd ed. New York, John Wiley & Sons, 1981. 21. Myers RH: Classical and Modern Regression with Applications, 2nd ed. Boston, PWS-Kent, 1990. 22. Kutner MH, Nachtsheim CJ, Neter J, Li W: Applied Linear Statistical Models, 5th ed. Boston, McGraw-Hill, 2005. 23. Tabachnik BG, Fidell LS: Using Multivariate Statistics, 4th ed. Boston, Allyn and Bacon, 2001. 24. Green SB: How many subjects does it take to do a regression analysis? Multivar Behav Res 26:499–510, 1991.
25. Harrell FE, Lee KL, Matchar DB, Reichert TA: Regression models for prognostic prediction: Advantages, problems, and suggested solutions. Cancer Treat Rep 69:1071–1077, 1985. 26. Peduzzi PN, Concato J, Kemper E, et al: A simulation study of the number of events per variable in logistic regression analysis. J Clin Epidemiol 99:1373–1379, 1996. 27. van Belle G: Statistical Rules of Thumb. New York, John Wiley & Sons, 2002. 28. Hsieh FY: Sample size tables for logistic regression. Statistics Med 8:795–802, 1989. 29. Kaplan EL, Meier P: Nonparametric estimation from incomplete observations. J Am Statistic Assoc 53:457–481, 1958. 30. Cox DR: Regression models and life tables (with discussion). J Roy Statist Soc B 34:187–220, 1972. 31. Harrell FE, Lee KL, Califf RM, et al: Regression modeling strategies for improved prognostic prediction. Statist Med 3:143–152, 1984. 32. Khamis HJ: Statistics refresher II: Choice of sample size. J Diagn Med Sonogr 4:176–184, 1988. 33. Khamis HJ: Statistics and the issue of animal numbers in research. Contemp Topics Lab Animal Sci 36:54–59, 1997. 34. Khamis HJ: Assumptions in statistical analyses of sonography research data. J Diagn Med Sonogr 13:277–281, 1997. 35. Gibbons JD: Nonparametric Statistical Inference, 2nd ed. New York, Marcel Dekker, 1985. 36. Sheskin DJ: Parametric and Nonparametric Statistical Procedures, 3rd ed. New York, Chapman & Hall, 2004.
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10
Ethics of Reproduction Pasquale Patrizio and Dorothy Greenfeld
INTRODUCTION
Autonomy
Reproductive medicine and the use of assisted reproductive technologies (ART) for the treatment of infertility have rapidly evolved. Because these techniques are directly involved in the handling of human gametes and embryos, they are open to a number of ethical analyses and moral concerns. In addition, with the practice of ART, the union in vitro of gametes has also created situations where the boundaries of science, religion, interest of the society, and family law are all intermingled with the rights of individuals to reproduce, thereby creating various dilemmas for both patients and professionals. The complexities of the different clinical scenarios call for the creation of policies—currently in the format of voluntary guidelines—so that ART clinics can utilize a rational approach when deciding in favor of or against participation in the use of technologies for a particular reproductive scenario. Before discussing some of the most common ethical dilemmas in ART, it is necessary to provide some background information and explain the most common medical ethical constructs used to formulate policies and guidelines.
Autonomy, or respect for persons, acknowledges an individual’s right to hold views, make choices, and take actions based on personal values and beliefs. This principle is at the base of informed consent and respect for privacy. In the reproductive field, this principle is the basis for reproductive rights and reproductive choices. Some examples: Should in vitro fertilization (IVF) be allowed for a woman who knows the donor of the sperm but does not intend to have a relationship with him? Should an unmarried woman be allowed to use donated embryos or sperm from a sperm bank? Should a woman in a long-term lesbian relationship be allowed to use sperm from a known or unknown donor? Should a widower be permitted to use embryos frozen while his wife was alive and to use a member of his or her family as a gestational carrier? Is it permissible to allow gay men in stable relationships to create families using donor eggs and surrogacy? As to each question posed, the formulation of guidelines must take into account the right of an individual to decide, with the understanding that procreative liberty has some limits when these rights conflict with the child’s interest. Beneficence
GENERAL ETHICAL CONSTRUCTS Any policy or guideline needs to have a certain degree of flexibility built in, because natural rights and human dignity, in the context of creating families, cannot always be clearly defined. We do not have unequivocal answers regarding when life begins, which leaves room for debate in the discussion of the ethics of researching on embryos to obtain stem cells. Furthermore, if we recognize the natural rights of individuals to reproduce, why should this right not be conceded to same-sex couples? It is understandably difficult to balance an individual’s right to reproductive autonomy and privacy with the societal obligations to protect the potentiality of life. A recent ruling by a judge in Chicago that a couple can sue a fertility clinic for wrongful death of an embryo not cryopreserved further exacerbates this moral confusion.1 The most common ethical norms used to conduct ethical analyses are based on principle-based ethics, communitarian-based ethics, and case-based ethics.
The principle of beneficence represents the obligation to promote the patient’s well-being. Beneficence represents the balancing of risks and benefits of an intervention. It is the principle that dictates that subjects be protected from harm and that efforts be taken to secure their well-being. It may conflict with the principle of autonomy. Examples where this principle comes into play include a patient who demands a cesarean section and a patient who requests the transfer of five or more embryos. Nonmaleficence
The principle of nonmaleficence is the obligation of “do no harm,” also known by its original Latin expression of “primum non nocere,” which must be balanced with the principle of autonomy. Both beneficence and nonmaleficence may overlap, as, for example, in the case of a patient who refuses to receive a lifesaving blood transfusion or a patient who, despite having a very little chance of success and despite previous IVF attempts, insists and demands additional IVF treatments. Justice
Principle-based Ethics The moral reasoning of principle-based ethics is based on four principles: autonomy, beneficence, nonmaleficence, and justice.
The principle of justice concerns fairness and equity (i.e., the need to be fair in sharing the burden [costs] and the distribution of resources [benefits] to all members of the community). In particular, the concept of distributive justice is often applied to situations requiring a decision about the equitable allocation of
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Section 1 Basic Science resources. The current practice of IVF, however, is not just. State variations in insurance coverage for IVF and the frequent determination by insurance companies that infertility is “not a disease,” make infertile low-income people unable to have access to these services. Particularly with third-party reproduction (egg donation and surrogacy), it is clear that at present, only wealthy couples can afford these reproductive services. In terms of research, the principle of justice stipulates that one class of persons, due to their inherent vulnerability, may not be overrepresented as research subjects so that others may benefit. Moreover, it means that these same classes of persons may not be unduly excluded from research participation and denied the benefits derived from it.
Communitarian-based Ethics In communitarian-based ethics, the moral reasoning emphasizes the interest of the community over individual autonomy. Solutions to ethical questions are to be formulated keeping in mind values and goals that benefit the need of many instead of few. Classical examples are the decisions to report cases of sexually transmitted disease (including human immunodeficiency virus). In ART the interest of the community could be affected if pre-implantation genetic diagnosis (PGD) for gender selection would be widely applied and would consistently favor the selection of one gender.
Case-based Ethics In case-based ethics, the moral reasoning is based on previous solutions set for specific cases. It is analogous to case law in jurisprudence and because it asserts priority of practice over theory, it may conflict with and reject the primacy of the principles. Because there is not one fundamental approach on which to rely exclusively, the practical use of medical ethics is a mix of all of these approaches. In summary, the moral principles should be applied in the context of community interest, respecting gender equality and building (if available) on the foundation of prior good ethical reasoning. There are several clinical situations that are common in reproduction and are associated with introspection and debate. Some of these case scenarios are reviewed in this chapter.
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Programs offering fertility services are increasingly faced with requests from women of advanced reproductive age who seek assistance to become pregnant. Oocyte donation has afforded older women the opportunity to give birth well beyond menopause, and many are taking advantage of this opportunity. Without clear guidelines programs have concerns about the ethical propriety of this extension of the normal reproductive age. As a result they struggle with the following questions: Given that menopause no longer constitutes a biological limit to reproduction, when is a woman too old to give birth? How should the risks of pregnancy in older women be weighed against the rights of women to control their own reproductive lives? How should a woman’s age and life expectancy factor into a clinic policy concerning these services? What do we know about the capacity for postmenopausal women to parent infants and toddlers? What do we know about the development of
children resulting from such services and how they fare as the children of comparatively aged parents? There is no question that the phenomenon of older women seeking to become pregnant through egg donation has increased greatly in the past decade. In the United States between 1991 and 2001, the birth rate for women between ages 40 and 44 increased by 70%, and in 2003 there were 263 births reported in women between ages 50 and 54.2 Although a small number of these births occurred spontaneously, most are attributable to egg donation.3 Why do women of advanced reproductive age want to have children? Their motivations vary widely. A part of the explanation involves the fact that women are marrying later in life, often working in pursuit of their careers and consequently postponing motherhood. Of these women, some have been involved in prolonged infertility treatment with no success and have been referred to egg donation. Others are divorced and remarried and want to have children with their new husbands. In some cases the death of a child prompts a woman to attempt to have another.4 One study found an increased incidence of cosmetic surrogacy among older candidates for oocyte donation and suggested that the desire for pregnancy in this population is motivated by the “desire for youth” and the younger appearance that pregnancy provides.5
How Old Is Too Old? The question, according to Sauer, has not been answered because the long-term consequences of pregnancy in older women are unknown. He describes the irony that older women, whose ages ordinarily would mean that they would have the poorest prognoses for pregnancy, with donor eggs now have the highest success rates in ART.6 The question of how old is too old presents an ethical dilemma for ART programs because the medical risks are disputable and guidelines for appropriate age restrictions are inadequate. Thus, programs offering oocyte donation are left to their own devices for determining age limits. Pregnancy complications in older women (women over age 40) are well known. They include pregnancy-induced hypertension, premature rupture of the membranes, vaginal bleeding, and gestational diabetes.3 Those arguing against ART for older women say that this treatment exposes older women to physical risks wholly different from those that younger women are exposed to—risks to the cardiovascular system, for example. Older women have a greater chance of postpartum hemorrhage and are at greater risk for perinatal mortality, cesarean section, and multiple gestations. Those in favor of this treatment argue that studies on older mothers are misleading because they include spontaneous pregnancies, women who have not been prescreened before pregnancy, women who are socioeconomically disadvantaged, and women who were in poor health before pregnancy.6,7 They contend that women over age 40 entering oocyte donation programs are typically rigorously screened before acceptance into the program. One study reported on women in their sixth decade of life who had safely delivered babies and presented no problems.6 Discipline-wide guidelines are inconsistent or entirely lacking, so programs have no generally accepted standards to provide guidance in making decisions about these patients. For example, the American Society for Reproductive Medicine (ASRM), in its Practice Guidelines, recommends that all recipients of oocyte donation over age 45 undergo thorough medical evaluation,
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Chapter 10 Ethics of Reproduction including cardiovascular testing and a high-risk obstetrical consultation before treatment. The guidelines do not include recommendations for age restrictions, however.8 A statement from the ASRM Ethics Committee asserted that oocyte donation to postmenopausal women “should be discouraged” and that patients and programs should determine on a case-by-case basis whether a woman’s health, medical and genetic risks, and provision for child rearing justify proceeding with treatment.9
What About the Children? Concerns about the children of older mothers seem to fall into two categories: one is about the life expectancy of the mothers and the fear that children will be orphaned at an early age; the other is about the health of the older mothers and the fear that they will not have the energy and the stamina to care for young children. The Human Fertilization and Embryology Authority (HFEA) law enacted in 1990 in the United Kingdom determined that recipients of donor oocytes should not be over age 45, based on the view that it is in the best interest of the child to be parented into young adulthood. Another clinician in the United States used the same argument—that children need an adult to raise them until they can live independently—but recommended that the treatment should be limited to women under the age of 60.10 Those arguing in favor of oocyte donation for postmenopausal women say that society is accepting of older men marrying younger women and having children, so to deny treatment to older women would be agist and sexist. In making this argument they ignore the fact that many older men are biologically capable of fathering children if they choose to do so, so that treatment issues enter into the equation only if donor sperm are required. They also argue that grandparents often take on the parenting role and “bring economic stability, parental responsibility, and maturity to the family unit,” so there is no reason to assume that older women would lack the stamina to raise children.9 It is unclear whether legislators or physicians are better able to judge an older woman’s suitability to be a mother than the woman herself. If an age guideline is to be evidence based, rather than a personal judgment, we presently do not have adequate data to determine an appropriate age limitation. Perhaps the most useful guideline would be to conduct a careful psychological evaluation of older women requesting this treatment, assessing their physical and emotional health status, and inquiring whether they have considered issues and potential problems of raising children in late middle age.
TREATING SAME-SEX COUPLES An increasingly common ethical concern in fertility treatment centers offering ART is whether or not to accept couples of the same sex as patients. Often the question applies only to gay male couples because many clinics may already routinely treat lesbian women. Yet in recent years gay men as well as lesbian women have become more open about their homosexuality, their relationships, and their determination to become parents.11,12 There has been dramatic recent growth in societal awareness about homosexuality and acceptance of same-sex civil unions. In addition, a growing body of research supports the notion that being reared in homosexual homes does not harm children and that such children are not more likely to become homosexuals
themselves.12 These factors have led more ART programs to consider treating same-sex couples of both genders. A recent survey of ART programs in the United States makes clear that there is no consistent policy regarding the issue of treating same-sex couples, although programs are more likely to reject gay males than they are lesbians.13 Neither is there consistency in ethical concerns about this treatment. Concerns range from questions about the health and well-being of children conceived in all homosexual relationships to specific concerns about the children of gay men. Some common questions about gay fathers include: Can men (and in particular, gay men) be sufficiently nurturing? Are gay men more likely to be pedophiles that abuse their children? Are the sons of gay men more likely to become gay? Others may question whether it is ethically acceptable for programs to accept lesbians for ART while refusing to treat gay males. Why do lesbian and gay couples want to become parents? It seems that they are motivated by the same factors that motivate heterosexuals to become parents. In fact, a recent study looked at desire and motivation for parenthood in 100 two-mother lesbian families compared to 100 heterosexual families. The author found that the desire to have children was stronger in lesbian women and that they gave more thought to the idea of having children.14 Gay males give the same reasons for parenthood that heterosexual males do; that is, the desire to nurture children, to have the constancy of children in their lives, and to achieve the sense of family that children provide.15,16 The health and well-being of the children of lesbian women conceived through ART has been described in several studies. Researchers found no differences between children raised by lesbian mothers and those raised by heterosexual mothers in terms of gender identity, behavioral development, and psychological development.11,17–21 A recent study, the first based on a national sample, compared 44 adolescents in lesbian families and 44 adolescents living in heterosexual families and found no significant differences between subjects on psychosocial adjustment, school outcomes, and romantic relationships.22 Adult offspring of lesbians were studied as well. Young adults between ages 17 and 35 who had been conceived in a heterosexual relationship but raised in a lesbian household were found to have healthy peer relations, to be psychologically stable, and to be no more likely to report same-sex attraction than offspring of heterosexual mothers.23 Though an estimated 6 to 14 million children in the United States live with at least one gay or lesbian parent, children of gay men have not been as thoroughly studied as those of lesbian women.12 For example, in a recent review of 23 empirical studies of children of gay and lesbian parents published between 1978 and 2000 only three studied gay fathers.24 Parental motivation was considered in a study comparing attitudes toward parenting of heterosexual and gay fathers. Gay fathers were more likely to express “the higher status accorded to parents as compared to nonparents” as a motivation for parenting. The authors also asked subjects to describe their interaction with their children. They found no reported differences in terms of intimacy or involvement with the children, although gay fathers reported greater warmth and responsiveness and more limit setting.15,16 Three studies examined the sexual preferences of adolescent and adult offspring of gay fathers and found that most reported a heterosexual orientation.25–27 Studies of gender identity, gender
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Section 1 Basic Science role behavior, and sexual orientation found no differences between children of gay men and children of heterosexual fathers. Children of gay fathers are not more likely to become homosexual nor are they more likely to be sexually molested by their fathers.28,29 Gay men who choose to become fathers within a gay relationship most commonly do so via adoption. However, the number of gay men who want to become fathers through ART is growing. Some become fathers through a coparenting arrangement with a lesbian whom they have artificially inseminated; others seek infertility treatment with a surrogate and egg donor.12 It appears that same-sex couples, including gay male couples, are increasingly determined to become parents and many are seeking infertility programs to assist them. Programs need to develop appropriate policies if they are to serve these couples with a focus on the specific needs and concerns they bring to the treatment. There is also a need for continuing studies of treatment outcome for gay couples to help improve the quality of care.
DISCLOSURE VERSUS NONDISCLOSURE WHEN USING DONOR GAMETES Failure to disclose the origin of the gametes among couples who have conceived a child through the use of donor gametes (whether eggs or sperm) is relatively common.30 Recently, however, many— particularly in European countries—are advocating that couples resorting to donor gametes for reproduction should be obliged to disclose the use of donor gametes to their children once they reach the age of understanding, following policies analogous to those governing disclosure to children that are adopted.31 However, mandating disclosure by a couple is problematic on a number of fronts, and the claim that the practice of gamete donation is similar to adoption is incorrect for many reasons. With gamete donation, one of the parents is the biological parent and the other is the social parent; with adoption, both parents are social parents. With gamete donation the child’s mother, whether biological or not, carries the pregnancy with all of the accompanying psychological interplay. In the case of a donor egg, to ask such a mother (and she is a mother under any definition of motherhood) to tell the child that technically she is not the mother because she is not totally genetically related would strain reasonable medical practice and certainly challenge the bond between mother and child.32 Certainly a preeminent concern is the welfare of the child. However, the benefits accruing to a child from disclosure are difficult to assess and still remain open to many interpretations. In debates about child welfare with adoptions, researchers and policy makers have not yet provided a consensus on what is the best interest of the child.33,34
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In addition to considerations of child welfare, one must address the impact on the other participants in the process, including the donor, the couple, and the healthcare providers. A donor has to be willing to donate his sperm or her eggs knowing that later he or she can be identified; the couple has to agree in revealing the origin of the gametes to their offspring; the providers have to restrict reproductive services only to couples who agree in writing to disclosure. Without uniform requirements for the collection and maintenance of records, the usefulness of revealing the
information is questionable. Accessing any such records from private clinics and banks is likely to be difficult, and certainly the quality of the information contained in them is uneven. In addition, where the child is not in physical harm, courts and legislatures are generally reluctant to intervene in family relationships, including questioning parental judgment about the best interests of the child.32 To force fertility specialists to participate in implementing forced disclosure is problematic as well. Including acquiescence to disclosure as part of screening criteria unjustly interjects social factors (vis-à-vis health factors) into criteria for program acceptance and encourages desperate couples to lie if they disagree. Because relationships vary greatly with background, ethnic origin, and attitudes of both the male and female partner, it would not be unreasonable for a healthcare provider to raise the issue of informing offspring of his/her genetic background at the time the use of donor gametes is considered by a couple. To do more than raise the issue and present known data on the potential psychological ramifications of disclosure and nondisclosure would violate the privacy of the couple’s relationship and interfere with their authority to decide. Programs that use donor gametes should, however, prepare policies on how to handle requests of information from children of donor gametes in future. They may choose to disclose only nonidentifying information when the requesting party has reached age 18, or they may disclose more based on the particular willingness of donors to remove more of their information from anonymity.35
PRE-IMPLANTATION GENETIC DIAGNOSIS Today there are a number of genetic tests available to detect single-gene and chromosomal disorders. Furthermore, new research tools are being implemented to aid in the discovery of how multiple genes interact in the etiology of multifactorial diseases. PGD allows screening of embryos produced in vitro for the disease of interest and the transfer of unaffected embryos. Some see this practice as reopening the issue of “eugenics” and opening the possibility of attempts to improve or manipulate the human gene pool, contending that this practice may convey negative messages about the social acceptability of genetic disorders and/or disability.36 Others argue that, on the contrary, PGD is providing information and allowing couples to make choices about the tests they have done (i.e., it is not an imposition from the state to the people) and reflecting the rights of individuals to choose what is best for them and their families. For women with a history of recurrent pregnancy loss, for carriers of known single-gene disorders (e.g., cystic fibrosis, Tay-Sachs disease) or balanced chromosomal translocations, and for women with recurrent failure to achieve a pregnancy after IVF, PGD is justifiable because it should decrease the overall reproductive risks. In fact, it should reduce the risk of pregnancy loss (by allowing transfer only of unaffected embryos) and it should reduce the need for terminating a pregnancy (by avoiding the late discovery of an abnormal fetus). Additionally, it should reduce the risk of multiple pregnancies and associated comorbidity (by transferring the single best embryo) and improve the overall efficiency of IVF (by avoiding embryo transfers when none of the embryos are normal). The ethical ramifications of PGD are essentially related to the issue of requesting PGD for nonmedical indications, such as
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Chapter 10 Ethics of Reproduction family balancing (also known as gender selection or preconception sex selection) and HLA-matching (also known as designer babies). Simply stated, is it permissible to sex embryos? And if not, what are the moral justifications to deny it? Is it morally justified to create embryos and then transfer only the ones HLA-matched with an existing sibling, so to design a perfect tissue donor? The medical reasons clearly offset the moral arguments of gender selection for the prevention of gender-specific genetic disorders (e.g., hemophilia [X-linked recessive]), muscular dystrophy or incontinentia pigmenti [X-linked dominant]). But in the absence of clear medical indications—as in the case of PGD for family balancing—the moral arguments to deny PGD service become stronger. The main concerns are based on the assumption that by offering sex selection on demand, the natural sex ratio would be altered, because in aggregate couples might request preferentially the gender of one sex over the other. It is therefore important to establish guidelines when the request of gender selection is made: (1) To correct a large disparity in the gender of one’s offspring (e.g., 4 boys and no girls). Would community gender ratio be impacted if PGD for gender selection were offered after the fourth child? Why not after the first or second? Or why not with the first? It could be argued that if consistently used to ensure the presence of one gender this could be discriminatory, but we have no data on this. (2) For personal or paternal preference for offspring of a particular gender. Is this request discriminatory? Does it violate dignity and natural rights of humans? (3) For cultural preference for offspring of a particular gender. In particular ethnic groups, the widespread preference for males would make gender selection unjust because it would distort evolution and limit reproductive options within that culture. As practiced today, this would clearly discriminate against female fetuses and violate their dignity and natural rights. Issues that need to be addressed for both human leukocyte antigen (HLA) matching and for gender selection requests are the fates of the non-HLA-matched embryos and of the embryos of the undesired gender. Using procreation and ART as a means to save another sibling life could be seen as exploitation. Creating a child (savior) whose own value and identity could later be affected by the act of being organ donor for their sibling requires a full psychological evaluation of the requesting families, and the risks of instrumentation and exploitation, albeit potential, need to be fully addressed. Currently, only a minority of couples seem to give importance to the sex of their children, and even fewer seem to be willing to use the service of preconception sex selection for nonmedical reasons.37
FERTILITY PRESERVATION: ETHICAL CONSIDERATIONS FOR ADULTS AND CHILDREN Adults The contemporary use of powerful chemotherapeutic and radiotherapy protocols are procuring cure or significantly extending survival for many patients with cancer. As a result of this progress
quality of life issues after cancer are emerging. Included in this quality of life paradigm is a consideration to protect fertility from the toxicity of these treatments. Many strategies have been devised to pursue fertility preservation, some well-established, such as embryo freezing (which is not always an option; e.g., unmarried women or young prepubertal girls); others, such as egg freezing and ovarian tissue freezing, still experimental. Likewise for men, the option of semen cryopreservation before chemotherapy or radiotherapy is well established, but scarcely used; spermatogonial harvesting and testicular tissue freezing for later autotransplant or xenografting are also still experimental. From an ethical standpoint, the key reason for pursuing fertility protection is to restore personal autonomy to those who are unable to conceive.38 However, because many of the technologies are innovative but experimental, it is difficult to design clinical trials: how to provide proper informed consent and respect for autonomy? Who to include or exclude in the trials? How to assess the risks? Can the moral principle of beneficence be upheld if ovarian tissue or testicular tissue cryopreservation poses future risks to any children who might result from this technique? Ideally the decision about who is a candidate for fertility preservation should be rendered by a team including a medical oncologist, reproductive endocrinologist, pathologist, and psychologist, all guided by written protocols that can be shared with patients.38 Patients should not be provided with false hopes, and alternative plans such as no intervention should also be part of the discussion. It is reasonable in the absence of grant funds to seek reimbursement from patients to cover the expenses of the research, but there should be no charge for clinical fees. Finally, for the time being, fertility preservation involving ovarian and testicular harvesting for freezing should be performed only in a few specialized centers working with proper International Review Board-approved consents.
Children Impaired future fertility is a remote consequence of exposure to cancer therapies that is difficult for children to conceptualize but potentially traumatic to them as adults. Unfortunately, the modalities that are available to children to preserve their fertility are limited by their sexual immaturity and are essentially experimental. For boys who cannot produce mature sperm, harvesting and cryopreservation of testicular stem cells with the hope of future autologous transplantation or in vitro maturation represents a promising method of fertility preservation. For girls, isolation and cryopreservation of ovarian cortical strips/primordial follicles followed by in vitro maturation of gametes when fertility is desired is a possible option. Extensive research is still required to refine these modalities in order to safely offer them to patients.38 Assisted reproductive technologies must be scrutinized on the basis of efficacy and subjected to rigorous ethical deliberation before they can be offered to patients. The modalities involved in fertility preservation of young children are no exception to this rule. In addition to ensuring that the basis for offering the intervention is morally just, the execution of the intervention must be deemed ethically sound. This determination requires that the intervention in question be evaluated within an ethical framework that considers it in terms of beneficence, respect for persons (autonomy), and justice.39 It can be argued that fertility preservation aimed at children is ethical because it prevents
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morbidity (reproductive and psychosocial) and safeguards their reproductive autonomy.40 Therefore, the main ethical question concerns the process involved in achieving fertility preservation and the techniques required. The answer is found in an exploration of the potential risks of the intervention to the patient and his/her progeny, the special situation of children as research subjects and patients, and the potential abuse of the technologies in the future.40,41 Children represent a unique and vulnerable population with respect to medical research. They have diminished autonomy, diminished capacity to understand the risks and benefits of research objectives, and lack the ability to provide consent for research studies. As a result, they require special protection against potential violation of their rights that may occur during research investigations.39,42 Until very recently, institutional attitudes impeded significant participation by children in medical research for fear of such exploitation.39 This attitude was attributed to several historical episodes of the unethical targeting of children as medical research subjects. One of the most notorious episodes was the Willowbrook Hepatitis Study, an examination of the natural course of infectious hepatitis and of the use of gamma globulin for its treatment and prevention. All children studied were patients at the Willowbrook State School—a New York State inpatient psychiatric facility. Enrollment into the study began in 1956. The subjects were deliberately infected with hepatitis by injection of purified viral preparations or by ingestion of stool extracts from infected persons. At one point during the study, admission to the hospital was contingent on permission to enroll a child in the study.42 Ethical guidelines to protect children as research subjects were outlined with the publication of the Belmont report in 1979, generated by the National Commission for the Protection of Human Subjects of Biomedical and Behavioral Research. Children should not be exploited to participate in pediatric research, nor should they be deprived of the benefits research has to offer because of their vulnerable status. Research involved in childhood fertility preservation should be conducted on patients who could experience personal benefit from the research, eliminating the prospect of exploitation for the gain of others. The immediate risks associated with gamete isolation to the individual child may be slightly greater than minimal. However, in the context of his or her illness this might be tolerable, especially if the procedure to procure the gonadal tissue is combined with a therapeutic procedure that requires anesthesia.43 Additional risks associated with fertility preservation are more difficult to assess due to the lack of data available to quantify them. For instance, the risk of reintroduction of malignant cells to the patient when gonadal tissue is autografted cannot be estimated becausee only limited animal data exist. Moreover, the risk to offspring conceived through such technologies, such as inheritance of genetic predisposition to cancer or other unforeseen genetic risks are unknown presently.40 Patients and their families must be informed of the potential benefits and the treatment alternatives for the process to be considered ethical. With respect to childhood fertility preservation, proper attainment of informed consent from a legally authorized representative (i.e., parent or guardian) and of childhood assent must be ensured.39,42 Assent— the active affirmation by the research subject—can be obtained from incompetent minors and it should be obtained from children whenever possible.
The benefits of gamete cryopreservation are promising, but they are largely unquantifiable because human data on the survival of gametes after the freeze-thaw-transplant process is limited. Until more data become available, we cannot tell patients what percentage of gametes will survive and what the probability of conception is and must not provide them with false hope. Alternatives to gamete cryopreservation should be discussed, and patients should be given the option of no intervention.40 Barriers to the consent process for fertility preservation interventions may develop. Parents may be competent to consent for their children, but the scenario is very complex both clinically and emotionally. Therapeutic obligations may limit the amount of time allotted to families to consent in a truly informed and voluntary way. It has been suggested that to overcome some of the practical obstacles involved in the consent process, it should be performed in stages.44 If a two-stage process is adopted, the issues of gonadal harvesting/storage and gamete manipulation could be handled as two separate subjects at two distinct time points. The decision to harvest gametes would be made at the time of cancer diagnosis and consent for the procedure would be left to parents/guardians. The decision of how to use the gametes after they have been isolated could be made at a future point by the patient in adulthood. At such a point in time, the patient would be better able to express personal preferences about the handling of the tissue based on an enhanced capacity to understand the nature and ramifications of the interventions proposed.
ETHICS OF EMBRYO RESEARCH FOR STEM CELL EXRACTION The subject of research on embryos created through IVF presents a variety of ethical and legal issues. The central part of the debate is the moral status of the embryo.45 This debate is not unique to the 21st century scientist or bioethics scholar; in fact it can be traced to Aristotle, who wrote of the “ensoulment” of the human at a particular stage, as did the pre-Socratic philosopher Heraclites before him. Religious views of conception have been extensively debated in Judeo-Christian and Muslim scholarship dating to the earliest religious texts in those traditions. The contemporary question of the moral status of the embryo emerged during the U.S. controversy over the legality of abortion in the 1960s through the 1980s, and continues to be a central issue in the discussion of embryo research as grounding for stem cell research. Views on the moral status of the human embryo normally take one of the following three forms: 1. The human embryo has no intrinsic moral status; it derives its value from others. 2. The human embryo has intrinsic moral status, independent of how others value it. 3. Embryos begin with little or no moral status and continue to achieve more and more status as they develop. The position that an embryo has no moral status can be argued in several different manners. Because the fetus fully depends on the pregnant woman for development, many ethicists believe that it cannot be viewed as a unique entity. The moral concerns expressed by those who hold this position about embryo research are focused on the long-term social implications of embryo research for the status of born persons, particularly those with
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Chapter 10 Ethics of Reproduction disabilities. However, it is not held that the destruction of an embryo is inherently morally problematic. The position that the fetus has intrinsic moral status is grounded in the view that a person is created at a moment in time that can be linked both to the consummation of an act by those who participate in its creation, and to the physical and legal initiation of that person’s participation in the human community. The metaphor most often used to describe the status of the fetus for these purposes is that of baby; the ever-increasing presence of the fetus in public and private life has contributed to the view that from the “moment” of conception a person can be identified, independent of the risks that face a person so defined, and regardless of the plain differences between such a person (e.g., in the case of a frozen embryo) and a person who participates as a baby, child, or adult in the institutional life of the community. Given this view of conception and the embryo, the use of an embryo for research purposes is exactly tantamount to the use of any other vulnerable subject in research without consent, research that poses not only a great risk, but in many cases also has the clearly anticipatable outcome of death for the subject. The moral issues surrounding embryo research leave the status of the embryo highly contested. The lack of consensus about the status of the embryo and the morality of research has resulted in what might be somewhat contradictory and unclear legal definitions in the United States at the state and federal level. Because it is extremely difficult to define the status of the embryo and the question still remains hotly contested, most of the legislation tries to steer away from making a definitive statement that would outrage either side of the debate. The legality of embryo research also varies from country to country. Experimentation on the embryo for the purposes of developing stem cell and other technologies, and for general knowledge, is legal in the United Kingdom and three Australian states under certain circumstances. In Germany and Italy, embryo research is banned completely. In the United States, debates over the legality of embryo research tend to pivot on prior state court holdings, federal agency rules and directives, or state laws on the status of the embryo. One’s position on the ethics of stem cell research depends on the question of when life begins and what bearing each developmental milestone has on the moral standing of a fetus, but also on the underlying view one holds about values and ethics. For the consequentialist theory, the ends determine an action’s moral status, and good ends justify the means necessary to achieve those ends. Embryos can be experimented on or even destroyed, because the ends of embryo research outweigh whatever damage is done to embryos—including the destruction of embryos—as long as it is clear that the embryo’s suffering or death is not more morally undesirable (to itself or to others, understood in a variety of ways) than is the suffering of the patient or community or family affected by a treatable or potentially treatable disease. Whatever its religious or scientific underpinnings, the ethical debate surrounding human stem cells has recently centered on how the human stem cells are derived and on whether or not they should be protected from destruction, much like an adult is.45 Using leftover IVF embryos for the purposes of human stem cell research raises complex questions about the status of the embryo, the value of human life, and whether limits should be set regarding the interventions into human cells and tissues.
Furthermore, questions about adequate informed consent, oversight, and regulation also come prominently into play. Those who support human stem cell research argue that an embryonic stem cell, even though it is derived from an embryo, is not itself an embryo and thereby would never continue to develop into a fetus, child, and adult. Each stem cell is only a cell that can be triggered to become a specific kind of tissue yet could not be triggered to become an individual. Furthermore, the embryo at the blastocyst stage has not developed any kind of nervous tissue, and thus extracting individual stem cells would not be painful for the embryo. Because the embryos used for stem cell research come mostly from leftover IVF embryos, which would otherwise be discarded, the proponents of stem cell research argue that it is better to use such embryos to find cures for debilitating diseases rather than to discard them, benefiting no one. One attempt to resolve the debate over stem cell research involved the suggestion that researchers might obtain stem cells from embryos without actually engaging in the destruction of those embryos.46 It also was suggested that totipotent cells might be removed from 4- or 8-cell preimplantation embryos destined for PGD.47
Embryos for Research Purposes Another ethical problem is the permissibility of making embryos specifically for research purposes. There are two different types of embryos used: those classified as “spare” embryos, which are left over from unsuccessful IVF, and those produced specifically for the purposes of being tested. Some people have ethical concerns about both of these methods; however, those who support research are more likely to question the ethical nature of the second of these two alternatives. The argument that it is acceptable to use spare embryos but not to create embryos specifically for that purpose centers on Kant’s categorical imperative, specifically the formulation of that imperative that centers on the claim that the ultimate moral wrong is to treat someone as a means to some other end, rather than as an end in himself or herself. Those who do not support the use of embryos for the sole purpose of enhancing research argue that it is morally unacceptable to use embryos for scientific purposes on the grounds that this is a clear use of a person as a means. Some of these same arguments can apply to the use of embryos under any circumstances. In the case of spare embryos, by contrast, many are too old or morphologically inappropriate to be implanted, and thus have no other use; it is thus argued that the use of these for research is not nearly as questionable.
Implications for ART Clinics The processes whereby embryos are created (whether from donor eggs and/or sperm intended for research purposes or as a byproduct of reproductive healthcare), analyzed, stored, thawed, or destroyed are all processes that require the technologies, clinical expertise, patient population, and institutions of ART. It is thus no surprise that the largest research programs in the field have employed reproductive endocrinologists, biologists, ART psychologists, and social workers. Ethical issues related to participation in stem cell research include three key problems. First is the question of whether and under what circumstances
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Section 1 Basic Science patients or research subjects should be allowed to participate in the donation of reproductive materials for stem cell research, particularly where that research involves the creation of embryos for research purposes. Second is the question of whether reproductive clinicians and technologists should be involved in the nonreproductive use of cloning technologies for the creation of nuclear transfer-derived stem cells. Third is whether and when
clinicians involved in the derivation of embryonic stem cells should be held responsible for the failure of those cells in clinical trials or therapies using those cells. At this time, on none of these issues is there professional consensus, although all three issues continue to receive the attention of the ethics boards of professional societies, such as the ASRM in the United States, and of bioethicists.
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1. The American Fertility Association: Life in a petri dish? Available at www.theafa.org. Accessed 10 Feb. 2005. 2. Heffner LJ: Advanced maternal age—How old is too old? NEJM 351:1927–1929, 2004. 3. Tarlatzis BC, Zepiridis L: Perimenopausal conception. Ann NY Acad Sci 997:93–104, 2003. 4. Cohen CB (ed): New Ways of Making Babies: The Case of Egg Donation. Indianapolis, Indiana University Press, 1996. 5. Sauer MV, Paulson RJ: Demographic differences between younger and older recipients seeking egg donation. J Assist Reprod Genet 9:400–402, 1992. 6. Sauer MV. Treating women of advanced reproductive age. In Sauer MV (ed): Principles of Oocyte and Embryo Donation. New York, Springer, 1998. 7. Sauer MV, Paulson RJ, Lobo RA: Pregnancy after age 50: Application of oocyte donation to women after natural menopause. Lancet 341:321–323, 1993. 8. American Society for Reproductive Medicine: Guidelines for oocyte donation. Fertil Steril 77(Suppl):S6–S8, 2002. 9. Ethics Committee of the American Society for Reproductive Medicine: Ethical considerations of assisted reproductive technologies. Fertil Steril 67(Suppl):25–35, 1997. 10. Mori T: Egg donation should be limited to women below 60 years of age. J Assist Reprod Genet 12:229–230, 1995. 11. Patterson CJ: Family relationships of lesbians and gay men. J Marriage Family 62:1052–1069, 2002. 12. Johnson SM, O’Connor E: The Gay Baby Boom: The Psychology of Gay Parenthood. New York, New York University Press, 2002. 13. Gurmankin AD, Caplan AL, Braverman AM: Screening practices and beliefs of assisted reproductive technology programs. Fertil Steril 83:61–67, 2005. 14. Bos HMW, Van Balen F, Van den Boom DC: Planned lesbian families: Their desire and motivation for children. Hum Reprod 18:2216–2224, 2003. 15. Bigner JJ, Jacobsen RB: Parenting behaviors of homosexual and heterosexual fathers. J Homosex 18:163–172, 1989. 16. Bigner JJ: Raising our sons: Gay men as fathers. J Gay Lesbian Soc Serv 10:61–68, 1999. 17. Braeways A, Ponjaert I, Van Hall E, Golombok S: Donor insemination: Child and family development in lesbian-mother families with children of 4 to 8 years old. Hum Reprod 12:1349–1359, 1997. 18. Golombok S, Tasker F, Murray C: Children raised in fatherless families from infancy: Family relationships and the socioemotional development of children of lesbian and single heterosexual mothers. J Child Psychol Psychiat 38:783–791, 1997. 19. Chan R, Raboy B, Patterson CJ: Psychosocial adjustment among children conceived via donor insemination by lesbian and heterosexual mothers. Child Dev 69:443–457, 1998. 20. Golombok S, Perry B, Burston A, et al: Children with lesbian parents: A community study. Dev Psych 39:20–33, 2003. 21. Flaks D, Ficher L, Mastepasqua F, Joseph G: Lesbians choosing motherhood: A comparative study of lesbian and heterosexual parents and their children. Dev Psych 31:105–114, 1995. 22. Wainwright JL, Russell ST, Patterson CJ: Psychosocial adjustment, school outcomes, and romantic relationships of adolescents with same-sex parents. Child Dev 75:1886–1898, 2004.
23. Tasker FL, Golombok S: Growing Up In A Lesbian Family: Effects on Child Development. New York, Guilford, 1997. 24. Anderssen N, Amlie C, Ytteroy EA: Outcomes of children with lesbian or gay parents: A review of studies from 1978 to 2000. Scand J Psychol 43:335–351, 2002. 25. Bozett FW: Gay fathers: How and why they disclose their homosexuality to their children. Fam Relat 29:173–179, 1980. 26. Bailey JM, Bobrow D, Wolfe M, Mikach S: Sexual orientation of adult sons of gay fathers. Dev Psychol 31:124–129, 1995. 27. Miller B: Gay fathers and their children. Fam Coord 28:544–552, 1979. 28. Mallon GP. Gay Men Choosing Parenthood: New York, Columbia University Press, 2004. 29. Jenny C, Roessler TA, Poyer KL: Are children at risk for sexual abuse by homosexuals? Pediatrics 94:41–44, 1994. 30. Klock S, Jacob M, Maier D: A prospective study of donor insemination of recipients: Secrecy, privacy and disclosure. Fertil Steril 62:477–484, 1994. 31. McGee G, Vaughan Brakman S, Gurmankin A: Disclosure to children conceived with donor gametes is not optional. Hum Reprod 16:2033–2035, 2001. 32. Patrizio P, Mastroianni A, Mastroianni L: Disclosure to children conceived with donor gametes should be optional. Hum Reprod 16:2036–2038, 2001. 33. Fernandez E: Significant Harm. Aldershot Brookfield, UK, Avebury Press, 1996. 34. Blyth E, Cameron C: The welfare of the child: An emerging issue in the regulation of assisted conception. Hum Reprod 13:2339–2342, 1998. 35. Ethics Committee of the American Society for Reproductive Medicine: Informing offspring of their conception by gamete donation. Fertil Steril 81:27–31, 2004. 36. Human Genetic Commission: Choosing the Future: Genetics and Reproductive Decision Making. London, United Kingdom Dept. of Health, July 2004. 37. Dahl E, Beutel M, Brosig B, Hinsch KD: Preconception sex selection for nonmedical reasons: A representative survey from Germany. Hum Reprod 18:2231–2234, 2003. 38. Patrizio P, Butt S, Caplan A: Ovarian tissue preservation and future fertility: Emerging technologies and ethical considerations. JNCI 34:107–110, 2005. 39. Hirtz DG, Fitzsimmons LG: Regulatory and ethical issues in the conduct of clinical research involving children. Curr Opin Pediatr 14:669–675, 2002. 40. Grundy R, Larcher V, Gosden RG, et al: Fertility preservation for children treated for cancer: Ethics of consent for gamete storage and experimentation. Arch Dis Child 84:360–362, 2001. 41. Thompson A, Critchley H, Kelnar C, Wallace WHB: Late reproductive sequelae following treatment of childhood cancer and options for fertility preservation. Best Practice Res Clin Endocrinol Metab 16:311–334, 2002. 42. Burns J: Research in children. Crit Care Med 31(Suppl):S131–S136, 2003. 43. Grundy R, Larcher V, Gosden RG, et al: Fertility preservation for children treated for cancer: Scientific advances and research dilemmas. Arch Dis Child 84:355–359, 2001. 44. Bahadur G: Ethics of testicular stem cells medicine. Hum Reprod 19:2702–2710, 2004.
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Chapter 10 Ethics of Reproduction 45. McGee G, Patrizio P, Kuhn V, Kraft-Robertson C: The ethics of stem cell therapy. In Patrizio P, Guelman V, Tucker M (eds): A Color Atlas for Human Assisted Reproduction, Laboratory and Clinical Insights. Philadelphia, Lippincott Williams & Wilkins, 2003, pp 297–309.
46. McDonald JW, Liu XZ, Qu Y, et al: Transplanted embryonic stem cells survive, differentiate, and promote recovery in injured rat spinal cord. Nature Med 5:1410–1412, 1999. 47. National Bioethics Advisory Commission. Ethical issues in human stem cell research 1999.
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Section 2 Pediatric and Adolescent Disorders Chapter
11
Normal Puberty and Pubertal Disorders Jonathon M. Solnik and Joseph S. Sanfilippo
INTRODUCTION The activation of the hypothalamic-pituitary-ovarian (HPO) axis represents the commencement of reproductive life in the adolescent female. Fantastic changes such as somatic growth and the development of secondary sexual characteristics occur as a result of a complex and well-orchestrated series of events that will lead to the propagation of life. From a less scientific and more cultural stance, puberty reflects the hallmark unveiling of adulthood. Accompanied by such drastic changes and novel responsibilities, it is an awkward and often challenging time for the young adult. It also presents the clinician with the opportunity to provide care to this vulnerable group of patients. A thorough understanding of the appropriate timing of events and an awareness of the stressors that frequently complement these changes is then essential for the pediatrician, gynecologist, or primary care provider.
–
The HPO axis lies dormant before puberty, although welldeveloped and functional during fetal development. In the higher cortical centers, from the arcuate nucleus of the hypothalamus, gonadotropin-releasing hormone (GnRH) is synthesized and released.1 This decapeptide is secreted in a pulsatile fashion and has a fleeting half-life of 2 to 4 minutes. Through its effect on the anterior pituitary, GnRH regulates the synthesis, storage, and release of the pituitary gonadotropins follicle-stimulating hormone (FSH) and luteinizing hormone (LH). These hormone levels approach those of an adult in the fetal circulation by midgestation. However, with increasing maternal steroid hormone production closer to term, gonadotropin levels decline. Shortly after delivery, as the maternal source of estrogen is withdrawn, gonadotropin levels are noted to increase as a result of the release from the negative feedback circuit.2 The HPO feedback system is illustrated in Figure 11-1. This sequence of events demonstrates the functional capability of the HPO axis early in development and results in follicular growth in the prepubertal ovary and an increase in circulating estradiol. This effective and exquisitely sensitive negative feedback system, often referred to as the gonadostat, develops rapidly, and in the years preceding puberty, gonadotropin levels remain low in response to suppression by low levels of circulating estrogen (10 pg/mL). It is thought that the two primary inhibitory influences on the pulsatile release of GnRH and the downregulation of the HPO
–
• GABA • Body composition/leptin
Hypothalamus (GnRH)
–
? Adrenal Gland Anterior pituitary (LH/FSH)
NORMAL PUBERTY Hypothalamic-Pituitary-Ovarian Axis
Central nervous system
Maternal sex steroid hormones
• DHEAS • Androstenedione
– Ovary • Estrogen • Testosterone • Androstenedione Figure 11-1 Neuroendocrine Control of the Hypothalamic-Pituitary Axis Sexual maturation begins with the activation of the hypothalamic-pituitaryovarian axis. Release of central nervous system inhibitory influence results in gonadotropin-releasing hormone (GnRH) secretion, which stimulates the anterior pituitary to produce the gonadotropins luteinizing hormone (LH) and follicle-stimulating hormone (FSH). Ovarian steroidogenesis follows, and the feedback circuit is created. Through an undetermined pathway, the adrenal gland begins to produce androgens, primarily dehydroepiandrosterone sulfate (DHEA-S).
axis during childhood are the (1) intrinsic central nervous system (CNS) inhibition via γ-aminobutyric acid and the (2) negative feedback system driven by ovarian steroid hormones.3,4 With continued maturation of the CNS after birth, a more profound internal inhibitory effect can be noted in reference to GnRHsecreting neurons. In premature infants with less developed neuronal pathways, pituitary gonadotropins are higher than in term counterparts, presumably due to a weaker inhibitory influence.5 The presence of a nonsteroidal regulator of these pathways is
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further substantiated by the ability of patients with gonadal agenesis to secrete moderate levels of gonadotropins in response to GnRH.6 Other potential executors of the CNS regulation of steroid hormone production have been assessed, but none have shown a definitive effect.
in GnRH pulsatility and pituitary response to GnRH.16 Increased levels of NPY have been documented in females with eating disorders such as anorexia nervosa and bulimia,17 indicating another possible correlation with percentage of body fat and reproductive potential.
Onset of Puberty
Characteristics of Sexual Development
The events that then lead to the onset of puberty are fairly well understood; however, the signal for the CNS to release its inhibitory influence on the hypothalamus remains a mystery. Pulsatile secretion of GnRH from the arcuate nucleus of the hypothalamus leads to gonadarche, documented by profound increases in sex steroid hormone production.1 Early pubertal changes are temporally associated with an increase in GnRH pulse frequency, primarily during the sleep cycle.7 As menarche approaches, GnRH pulses increase in amplitude and can be detected throughout the day, similar to those in an adult.8,9 Ovulatory cycles occur with the arrest of the inhibitory effect of the CNS, and regulation of the HPO axis is then managed primarily by circulating steroid hormones via functional feedback circuits. LH and FSH are also released in a pulsatile fashion, which increases with the preceding increase in GnRH activity. In prepubertal girls, FSH responses to GnRH action are marked, whereas the response seen by LH is quite low (LH/FSH ratio < 1). Conversely, during puberty, a predominant LH response is seen and the LH/FSH ratio reverses. LH pulsatility is always dependent on GnRH secretion regardless of age, whereas there is a diminished FSH response to GnRH with the increase in ovarian activity that occurs during puberty.10 This may help explain the dichotomous maturation of the LH/FSH response. Both genetic and environmental pressures may play a role with the initiation of pubertal development. It has been suggested that appropriate weight gain and percentage of body fat are required for these events to occur.11 This postulate is based on data from adolescent females who suffer from chronic illness, malnutrition, or have low body mass indices due to extreme athletic pursuits. These young girls frequently have delays in sexual maturation and often present with primary amenorrhea resulting from hypothalamic hypogonadism. Normal menstrual cycles resume with reversal of their nutritional status.12 Whether the increase in body fat occurs as a result of these hormonal changes or whether it is a prerequisite for activation of the HPO axis was challenged by investigators who followed healthy females throughout puberty and found that body composition did not change prior to, but rather along with, the increase in GnRH secretion.13 Leptin, an adipocyte-derived hormone, has received much attention in recent years. Plasma concentrations correlate well with body composition and have been shown to rise throughout puberty in female patients.14 Accordingly, several investigators have attempted to establish a causal relationship between leptin and the activation of the HPO axis. Specific leptin deficiencies have been shown to prevent sexual maturation, which can then be triggered by restoring normal levels.15 Nevertheless, the role of leptin in pubertal development has not been clearly elucidated. Another molecule that may play a role in the reversal of HPO downregulation is neuropeptide Y (NPY). Circulating levels are regulated by steroid hormones as well as nutritional status, with a net influence on gonadotropin synthesis through an alteration
The series of events that occur during puberty have been welldefined. These predictable events, which are currently utilized as the standard for sexual development and somatic growth, were initially described by Tanner and Marshall more than 30 years ago (Fig. 11-2).18 Tanner stages describe characteristic (1) breast development, (2) pubic hair distribution, and (3) growth and maturation of genitalia by dividing each into five groups. For each characteristic, Stage I describes the prepubertal state and Stage V represents adult development. These guidelines are traditionally used to determine if an adolescent female is developing in a typical fashion. Thelarche
The first sign of development in the majority of white females is breast budding. According to Tanner and Marshall, this initial event occurs between ages 8 and 13 in most, with a mean of 10.6 years. The transition period from Stage II to Stage V breast development may last 4.2 years.18
Pubic hair
Breast I
Prepubertal
Prepubertal
II Sparse, lightly pigmented chiefly along the medial border of the labia major
Breast and papilla are elevated as a small mound. Areolar diameter increases III
Darker, beginning to curl, increased amount spreading over the mons
Further enlargement of the breast bud with loss of the contour separation between breast and areola IV
Increased amount of coarse, curly but limited to the mons
Areola and papilla form a secondary mound
V Mature areola is part of the general breast contour
Adult feminine triangle with spread to the medial surface of the thighs
Figure 11-2 Tanner Staging. Stages of female breast and pubic hair development during puberty as described by Marshall and Tanner. (From Marshall WA, Tanner JM. Variations in pattern of pubertal changes in girls. Arch Dis Child 44:291, 1969.)
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Chapter 11 Normal Puberty and Pubertal Disorders Adrenarche
Pubic hair growth typically occurs after thelarche but may occur concomitantly, with the activation of the hypothalamic-pituitary axis. Although adrenarche may also present before breast development in a normally maturing female, adult hair distribution should not be detected at this early stage; if present, it may represent an excess of androgen production. Accordingly, breast maturation should not be so advanced in the absence of pubic hair development, a potential sign of androgen insensitivity syndrome. Adrenarche typically occurs between ages 11 and 12, with adult hair distribution by age 14. Androgen levels change without a corresponding change in corticotropin and cortisol secretion throughout life. And so, the means by which adrenal androgens are produced is not as clearly delineated and appears to occur independent of the hypothalamic-pituitary axis. Perhaps the control of adrenal androgen production is intrinsic to the gland itself by means of key regulatory enzymes. Growth Spurt
The growth spurt (peak growth velocity), during which adolescents achieve approximately 20% of their adult final height, occurs with the onset of puberty (Fig. 11-3).19 Peak growth velocity (2 to 3 cm/year) precedes menarche and typically occurs earlier in girls than in boys. Rapid growth of the extremities occurs first, followed by a gradual lengthening within the vertebral column. The timing of the growth spurt varies according to ethnicity and environmental factors that may influence the onset of puberty. Growth charts are useful in predicting final height achievement. There are conflicting reports in reference to final height and timing of the onset of puberty. Patients with a later onset had smaller gains throughout puberty; however, they were initially taller than those who had earlier onset. Final adult height among these groups was comparable.20,21 Growth hormone through the actions of insulin-like growth factor I (IGF-I) is likely the principal factor responsible for somatic growth and final height. As low levels of sex steroid hormones rise early in puberty, there is
Height spurt
Menarche
Breast 2 (Tanner stage) Pubic hair (Tanner stage) 8
9
10
3 2
4
3
4 3 4
11
12 13 Age (years)
According to Tanner, girls in the United Kingdom in 1969 had their first menses at the average age of 13.5 years, with a range of 9 to 16 years.18 The mean age of menarche for a white adolescent in the United States is approximately 12.7 years. At the time of menarche, most have achieved Tanner Stage IV breast development,18 and the interval from initial breast development to menarche is 2.3 years.18 There seems to have been a decline in the average age of menarche in the first half of the 20th century, in part due to the improvement in general health and nutrition.23 Nonetheless, few reports have documented any further changes since the mid-20th century. There is good evidence that African-American girls have an earlier onset of puberty compared to white girls.24,25 This was well demonstrated by the Pediatric Research in Office Settings (PROS) study published by Herman-Giddens in 1999.24 This multicenter, cross-sectional study evaluated over 17,000 female patients between ages 3 and 12.24 On average, African-American females show early signs of puberty up to 1.5 years earlier than their white counterparts. By age 7, 27.2% of African-American girls and 6.7% of white girls showed breast or pubic hair development. Menarche was achieved almost a year earlier. The mean age for onset of breast development was 8.87 years in AfricanAmerican girls and 9.96 years in white girls. At each consecutive stage of development, African Americans were more advanced per year than white girls. Girls of other ethnic backgrounds may also demonstrate characteristic differences in onset of pubertal maturation. However, only white and African-American girls were included in this study. The PROS was the first large publication to address current and demographically relevant standards for assessing normal and abnormal onset of puberty. Updated guidelines have since been proposed and recommend a formal evaluation for precocious puberty be initiated in African-American girls who present before age 6 and white girls who present before age 7. Although this provocative investigation has drawn much criticism, it does invite us to reconsider the current standards (see Fig. 11-3).
The first gynecologic encounter is an event that the patient may remember for years to come. It is paramount that she understands the confidential agreement she has made with the healthcare provider.
5
2 2
Menarche
History and Physical Examination
5
3 4
a concomitant increase in the pulsatile secretion of growth hormone. As such, the initial growth spurt typically occurs before advanced secondary sexual characteristics appear. Higher levels of estrogens suppress the action of IGF-I, and so the same factors that promote growth can also impact final height by inducing epiphyseal closure.22
5 5 14
15
16
17
Figure 11-3 Timing of events of puberty. 1969 data (purple) from a study of British schoolchildren. 1997 data (green) from a study of American schoolchildren. (From Marshall WA, Tanner JM. Variations in pattern of pubertal changes in girls. Arch Dis Child 44:291–303, 1969; and Pediatrics in Review, Vol 8, no 2. Columbus, Ohio: Ross Laboratories, 1986.)
History
A thorough and comprehensive history should include past medical and family history, as well as social and academic concerns. Psychosocial history should be obtained, focusing on relationships with peers, authority figures, parents, teachers, coaches, as well as siblings. A nutrition history focused on fad diets, fast food, and overt eating disorders should be assessed.
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Section 2 Pediatric and Adolescent Disorders At times, it may be necessary to excuse the parent to address specific issues that the adolescent may feel uncomfortable discussing with the parent present. This may include issues dealing with sexual health and contraception. The clinician should be aware of specific state laws regarding consent and reporting. All states allow for the treatment of minors without parental consent, specifically for sexually transmitted diseases and routine obstetrical care. A trusting relationship often requires several visits, and confidentiality must be assured from the beginning. Comments should not be judgmental on the part of the healthcare provider. Physical Examination
During the physical examination, a chaperone should be present. In addition to an approach similar to that used for the adult, information regarding Tanner staging as related to breast and pubic hair development is appropriate. The physical examination should include a pelvic examination in the sexually active adolescent or individual over age 18. Cervical cytology should be obtained by age 21 or 3 years after initiation of sexual activity. Psychosocial Concerns and Sexuality
Although cognitive function may not be impaired with the great changes that occur during puberty, the social concerns that commonly afflict these young teens may influence overall functioning. Appearance plays a crucial role in social acceptance among peers and may be affected by the development of acne vulgaris, a common occurrence during puberty. Excessive acne should prompt the physician to rule out endocrinologic abnormalities such as nonclassic congenital adrenal hyperplasia or other disorders related to androgen excess. An adolescent female who has earlier but normal onset of puberty may be taller than her peers. As a result, she may be taunted by her classmates and feel isolated from her peers. Episodes of depression may be twice as common in girls as in boys after the onset of puberty.26 Human sexuality includes the physical characteristics and capacity for sexual activity, together with psychological values, norms, attitudes, and learning processes that influence behavior. Human sexuality involves a sense of gender identity and related concepts and attitudes about self and other women in the context of society. As children become adolescents, concrete thought processes become more abstract. The ability to think in this manner is achieved by age 15 to 16 . As a result, sexual curiosity may be apparent; contraceptive measures may not be well thoughtout. Healthcare providers should take the time to educate these young adults to prevent unwanted pregnancies and limit sexually transmitted infections.
PRECOCIOUS PUBERTY
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In the presence of ovarian or adrenal steroid hormones, the phenotypic changes that occur with sexual maturation will be apparent regardless of age. Both the physical and psychological stigmata associated with early onset of puberty can produce significant distress felt by the developing child and her family. Hence, it is crucial not only to identify children with signs of precocious puberty, but to also have a thorough understanding of the processes that result in abnormal sexual development. Shortand long-term concerns of social adjustment, final height, and reproductive potential must be addressed early in the course of the evaluation.
Effects of Precocious Puberty on Adult Height Low levels of estrogens have been shown to promote bone growth, as is manifest by rapid growth velocity during the growth spurt. Conversely, high levels promote closure of the epiphyseal plates. Girls who present early in the course of central precocious puberty are generally taller than their age-respective cohorts due to increased levels of steroids and the actions of IGF-I. This growth is premature and limited, so that the final height in untreated patients will likely be less than 155 cm.27 As a result, by the time most adolescents achieve menarche, they have likely reached their final height. Notwithstanding the apparent risk for short stature, a significant number of untreated patients with idiopathic disease will likely attain relatively normal adult height, greater than the 3rd percentile.27
When to Initiate an Assessment One challenge each clinician faces is when to initiate the assessment of a child suspected of having precocious puberty. Historical accounts from the 19th century report a relative later age of onset of menstruation (16 to 17 years), presumably due to malnutrition. The definition of precocious puberty has since remained stable, such that any female who presented before age 8 was observed, if not evaluated, for progression of sexual growth.18 As referred to earlier, the traditional definition was challenged by Herman-Giddens, who strongly suggested that normal pubertal development may begin as early as age 6.24 Isosexual precocity is characterized by early onset of otherwise normal physiologic development. This heterogeneous disorder can be categorized into central (GnRH-dependent), peripheral (GnRH-independent), or incomplete precocious puberty. Heterosexual precocity is evidenced by excessive androgen production and virilization of a female child. Causes of precocious puberty are listed in Table 11-1.
Central Precocious Puberty Central precocious puberty is more frequently noted among girls, with an incidence of 1:5,000 to 1:10,000.28 It results
Table 11-1 Causes of Precocious Puberty Central precocious puberty (GnRH-dependent) Idiopathic CNS tumors Craniopharyngiomas Trauma Infection Primary hypothyroidism Syndromes associated with elevation of gonadotropins Silver’s syndrome (dwarflike characteristics) Peripheral precocious puberty (GnRH-independent) Exogenous steroids (estrogens) Ovarian tumors Granulosa cell Adrenal Functional cyst McCune-Albright syndrome Heterosexual precocious puberty Exogenous steroids (androgens) Adrenal and ovarian androgen-producing tumors
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Chapter 11 Normal Puberty and Pubertal Disorders from premature activation of the hypothalamic GnRH neurons. Approximately 70% to 90% of such cases are idiopathic in nature; however, other potential etiologies must first be considered.29,30 Recent evidence suggests an inheritable risk with an autosomal dominant mode of transmission for certain cases of central precocious puberty.31 Approximately 27% of 453 Israeli children evaluated for precocious puberty were determined to have a familial form of central precocious puberty. Although a small study, it is consistent with the current opinion that the majority of cases of central precocious puberty are constitutional in nature. Known organic causes of central precocious puberty, however, include a multitude of CNS lesions. These include benign hamartomas, space-occupying lesions that can involve the hypothalamus and result in early precocious development, generally before age 4.29,30 Other differential diagnoses of central precocious puberty include congenital hydrocephalus, neural tube defects, CNS irradiation, encephalitis, and neurofibromatosis type I.32 While evaluating a child with precocious puberty, it is important to remember that this disorder may not progress along a well-defined course. Central precocious puberty is a dynamic condition in which the initial presentations may be similar, but the eventual clinical manifestations may vary significantly. Hormonal assays will be considerably different in girls with central, peripheral, or incomplete precocious development. A group of patients given the diagnosis of central precocious puberty may also progress at different rates, some slowly and others quite rapidly. This not only presents a challenge to the clinician, but it also confirms the need for longitudinal follow-up to provide the most accurate diagnosis and appropriate therapy.
History The initial assessment should begin with a thorough history to include age of onset, progression of secondary sexual characteristics, and linear growth for at least 6 months. Patients typically present with a complaint of breast budding and/or pubic hair growth, similar to that encountered with early physiologic puberty. In the absence of a foreign body or infection, vaginal bleeding may also signal the onset of central precocious puberty. The parents may be able to provide helpful information in regard to other family members who had early onset of sexual development. They may also have birth records, potentially eliminating a CNS insult or congenital adrenal hyperplasia as a differential diagnosis. A careful review of systems should be included to evaluate for persistent neurologic or psychological complaints indicative of a CNS lesion. Abdominal pain or discomfort could be a presenting symptom of an abdominal tumor. Nutritional status should also be determined, especially when dealing with young athletes.
Physical Examination Height and weight should be charted on a linear growth curve and followed until final height is achieved. Predicted final height has traditionally been based on the methodology described by Bayley and Pinneau.33 Target height (cm) considers genetic potential and is calculated from the averages of the height of the child’s parents:
girl = [(father’s height – 13) + mother’s height] / 2 boy = [father’s height + (mother’s height + 13)] / 2 Physical findings suggestive of central precocious puberty include Tanner Stage II breast development with darkening of the areola, labial fullness with a dullness of the vaginal mucosa, and leukorrhea. Coarse pubic hair, acne, oily skin, clitoromegaly, and deepening of the voice are signs of androgen production, which may occur in the setting of heterosexual development and should likewise be investigated. Tall stature and adult-type body odor are other indications that should prompt an evaluation for precocious puberty. A complete neurological examination, psychological evaluation, and skin assessment should be performed initially and with subsequent visits as well. A pelvic examination can be accomplished first by a thorough abdominal examination followed by inspection of the genitalia. Assistance from the child’s parent is especially helpful in accomplishing this task. Attempt to examine the patient using a gentle tact rather than being forceful. Fortunately, a bimanual examination is often unnecessary. In the event that an intra-abdominal tumor or foreign body is suspected, proceeding to the operating room with use of moderate sedation or general anesthesia may be advisable. A vaginal smear in an estrogenized system will reveal increased numbers of superficial squamous cells. An estrogensecreting tumor may be suspected when more than 40% of the cells are superficial and when rapid increase in height is noted. As previously mentioned, if extensive virilization is noted in the absence of estrogenic effects, evaluation for an androgenproducing tumor is indicated.
Laboratory Findings The function of the HPO axis is assessed using hormone assays. Baseline gonadotropin levels in the pubertal range with a predominant LH response is suggestive of central precocious puberty. Random daytime levels may be of less use in early central pubertal development because the initial increase in pulsatility occurs at night. To help distinguish central precocious puberty from GnRHindependent forms of precocious puberty, a GnRH stimulation test should be performed. To accomplish this, 100 μg of GnRH (gonadorelin acetate) is administered intravenously and gonadotropin levels are drawn at baseline and at 20, 40, and 60 minutes following. One of the earliest signs of physiologic puberty is the nocturnal, pulsatile secretion of GnRH with a subsequent increase in serum LH. There is a corresponding rise in LH for each pulse of GnRH secreted. As one would suspect, these same events occur with early onset, and an LH/FSH ratio greater than 1 would be expected. Serum estradiol levels in the pubertal range would be detected as well. To maintain the diagnosis of central precocious puberty, androgen (DHEA, DHEA-S, testosterone) and 17-hydroxyprogesterone (17OHprogesterone) levels should be drawn. The diagnostic values for GnRH-independent and incomplete forms of precocious puberty are discussed later in this chapter.
Imaging Studies Imaging studies play a key role in the evaluation of children with precocious puberty because a rapid increase in growth and bone
161
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Section 2 Pediatric and Adolescent Disorders age are typically seen in children with rapidly increasing levels of sex steroid hormones. Linear growth and skeletal maturation are often a more accurate assessment of pubertal development than progression of secondary sexual characteristics. Bone age is typically evaluated by radiographic plain films of the left hand and wrist. This is a simple and noninvasive test that is well tolerated by most children. Bone age advance over chronological age is diagnostic for precocious puberty, and a disparity of greater than 2 years is more suspicious for a progressive disorder.34 Given the higher prevalence of CNS abnormalities, neuroimaging is always indicated to rule out space-occupying lesions, malignant neoplasms, and other CNS anomalies even in the absence of neurologic complaints. A diagnostic approach to precocious puberty is given in Figure 11-4.
Treatment The ultimate therapeutic goal is to suppress the HPO axis and return the hormonal milieu to that of the prepubertal state (serum estradiol < 10 pg/mL). Of great clinical significance is the normalization of linear growth velocity and bone maturation. Clearly, the decision to proceed with any therapeutic intervention depends on the ability to correctly diagnose a progressive condition that will result in detriment to the child. The outcome for patients with central precocious puberty can vary significantly, which further limits our ability to predict who will benefit most from therapy. Psychological Issues of Premature Puberty
An important goal of treatment is to reverse sexual maturation, thereby limiting psychosocial repercussions and early reproductive potential. Girls who experience early puberty are at risk of persistent difficulty during adolescence.35 It is important to remember that these patients are young and naïve, and lack the psychosocial maturity often expected of them given their
appearance. It is also reasonable to assume that due to early physical development, sexual activity and the potential for abuse may occur at an earlier age. It is assumed that these reasons explain why girls with precocious puberty have been found to have more emotional problems, increased antisocial behavior, and are at risk for both dropping out of school and early pregnancy. For this reason, the parents of these girls should be made aware of these potential problems so that appropriate counseling and preventive efforts can be made.36 Hypothalamic Suppression
Initial attempts to achieve such a degree of hypothalamic suppression included the use of progestins; however, these were unsuccessful at limiting progressive changes and their use has since been abandoned.37 The use of GnRH analogs to treat central precocious puberty was popularized more than 20 years ago and has become the gold standard of therapy. The most commonly used preparations in the United States are leuprolide, nafarelin, and goserelin. Children with precocious puberty generally require higher doses to achieve suppression, which can be monitored with serum estradiol levels and GnRH stimulation tests. To improve compliance, subcutaneous formulations are currently used. Monthly intramuscular injections are also available. Early treatment protocols using long-acting GnRH agonists reported significant regression of secondary sexual characteristics and overall improvement in final height compared to nonrandomized controls.38 The difficulty with interpreting these results came from the lack of well-designed randomized trials and a limited ability to accurately predict adult height. In the absence of a more effective system, the methodology described by Bayley and Pinneau more than 50 years ago has been maintained throughout the literature despite the potential for overestimating predicted final height.39 Furthermore, children with suspected idiopathic precocious puberty were grouped together,
Breast development (<7 years)
Normal bone age Prepubertal LH and FSH
– Virilization
Advanced bone age (GnRH stimulation test)
+ Virilization
High FSH response
DHEAS
Premature thelarche Premature adrenarche • Elevated DHEAS
162
Figure 11-4
Elevated
Normal
Adrenal tumor
Cushing’s syndrome Ovarian tumor CAH
Premature thelarche Hypothyroidism
Evaluation of central, peripheral, and incomplete precocious puberty.
High LH response
Prepubertal LH + FSH levels
MRI
Pelvic/renal sonogram
GnRH dependent
GnRH independent
Constitutional CNS tumor CNS malformation
McCune-Albright ovarian tumor Adrenal tumor
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Chapter 11 Normal Puberty and Pubertal Disorders and the investigators did not delineate which of the patients were more at risk for significantly shortened stature. This, in part, is due to our inability to properly identify such patients. The variable presentation of central precocious puberty creates a dilemma for investigators who would otherwise design a randomized trial. Several months of simple observation are often required before progression can be documented. A few randomized series have been published that addressed the effect of GnRH agonists on final height in girls who presented with early or slowly progressive puberty.40,41 They confirmed results from previous observational and nonrandomized reports, which documented very little effect of hypothalamic suppression on improving final height in patients presenting at a later age. Furthermore, children presenting with either “early puberty” or advanced “slowly progressive puberty” were likely to achieve reasonable adult height without hypothalamic suppression. One theory that may help explain impaired growth during GnRH analog therapy in this group is early growth plate senescence related to estrogen exposure before onset of treatment.42 And so it may be this rate-limiting step, patients presenting beyond the window of opportunity, which limits final height. A summary of predicted and final height in patients treated for CPP is provided in Table 11-2. Significant consideration should then be given to promptly initiating therapy in girls presenting early with advanced bone age, because they will likely benefit most from GnRH agonist therapy.43–46 The question still remains as to what criteria should be used to determine maximum therapeutic benefit. Adan and colleagues suggested the following as risk factors for decreased stature and appropriate indications for therapy, especially at an earlier age of onset: (1) predicted adult height below 155 cm (may include those with a predicted height over 155 cm if the LH/FSH ratio is consistent with central precocious puberty) and (2) bone age advanced over chronological age by more than 2 years.46 Hormonal monitoring of therapy can be performed with the GnRH stimulation test at 3, 6, and 12 months after initiation, with annual follow-up thereafter. Although the optimal time of discontinuing therapy remains unclear, many recommend that suppression stop at a bone age of 12 to 12.5 years. Other elements to consider include the total
Table 11-2 Comparison of Predicted, Target, and Final Height in Patients with Central Precocious Puberty Predicted Height (cm)
Target Height (cm)
Final Height (cm)
Source
Study Design
Treatment Arm
Sigurjonsodottir et al.27
Observational
None
–
–
153.2
Sorgo et al.37
Observational
Cyproterone
157.1
153.1
161.0
Kauli et al.39
Observational
Triptorelin
156.6
157.7
159.6
Brauner et al.45
Prospective Triptorelin Non-randomized
153.4
159.1
157.4
Bouvattier et al.40 Prospective Randomized
Triptorelin
154.1
157.6
157.6
Cassio et al.41
Prospective Randomized
Triptorelin
158.0
157.0
158.1
Adan et al.46
Prospective Triptorelin Non-randomized
156.0
161.2
159.5
duration of therapy and growth velocity over the months preceding. Routine evaluation of secondary sexual characteristics, weight, and sonographic measurements of pelvic structures should be performed on an ongoing basis as well. Bone mineral density may be affected by prolonged use of GnRH agonists, and so attention to bone health should not be omitted. Recombinant Growth Hormone
Some children with precocious puberty will have early closure of their epiphyseal plates despite the use of GnRH analogs. As a result, these girls will grow up to be short adults without further intervention. Since the 1980s, recombinant human growth hormone (somatropin) has been available to treat patients with growth hormone deficiency and other conditions associated with poor growth. The use of growth hormone as an adjunct to GnRH agonists in girls with precocious puberty has been evaluated by several observational and randomized series and has been found to improve final height prognosis.47 Early initiation of therapy in patients with central precocious puberty may further enhance the response. The long-term effects of prolonged therapy with growth hormone, outside of bone growth, are unknown. Although the use of growth hormone in certain patients has become extremely popular among pediatric endocrinologists, the studies evaluating efficacy are troubled by obstacles quite similar to those seen with the analysis of GnRH agonists on final height: patient compliance, dosing, and the inability to monitor efficacy. Care should then be prescribed when administering growth hormone in patients whose final height is expected to be within normal adult range, and a thorough discussion with the child’s parents should precede such therapies. It is important to be aware that growth hormone has not yet been approved by the U.S. Food and Drug Administration for treatment of girls with short stature as a result of precocious puberty.
GNRH-INDEPENDENT PRECOCIOUS PUBERTY When precocious puberty occurs independent of pituitary gonadotropins, the source of estrogen production must be established. One common source is surreptitious ingestion of exogenous hormones, such as those found in oral contraceptive pills or anabolic steroids. Other less common sources include primary hypothyroidism. However, the most common origin of GnRHindependent estrogen production is frequently the ovary itself.
Autonomous Ovarian Estrogen Production Ovarian tumors are uncommon but important childhood neoplasms that present with precocious puberty in approximately 10% of cases.48 Granulosa cell tumors are the most common estrogenproducing neoplasms detected. However, other tumors, such as thecal cell tumors, gonadoblastomas, teratomas, cystadenomas, and ovarian cancers, may be responsible. Intra-abdominal masses are often palpable, but sonography or magnetic resonance imaging (MRI) may help characterize the tumor, and surgical exploration is generally warranted. Laboratory criteria that help distinguish these processes from a central source include low baseline gonadotropin levels and a prepubertal response to the GnRH stimulation test. As with central precocious puberty, estradiol levels will be high and bone age
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Section 2 Pediatric and Adolescent Disorders advanced (see Fig. 11-4). Treatment is based on surgical extirpation of the source, which results in regression of pubertal changes.
McCune-Albright Syndrome McCune-Albright syndrome, also known as polyostotic fibrous dysplasia, is a genetic disease affecting the bones and pigmentation of the skin. The hallmark of McCune-Albright syndrome in girls is precocious puberty, and this condition accounts for approximately 5% of cases with with precocious puberty. These patients have estrogen-producing ovarian follicular cysts that develop independent of gonadal hormone stimulation, a condition termed autonomous follicle development. Menstrual periods usually begin in early childhood, long before the appearance of breast buds or pubic hair development. Children with this rare disorder also have fibrous dysplasia in their bones, which leads to fractures, deformities, and X-ray abnormalities. Facial bone deformities may cause cosmetic problems. In addition, these children have café-au-lait spots, which are light tan birth marks. McCune-Albright syndrome is often associated with several other endocrinopathies, including hyperthyroidism, acromegaly, pituitary adenomas, and adrenal hyperplasia.49 McCune-Albright syndrome is caused by a postzygotic somatic mutation in the GNAS-1 gene that is sporadic rather than inherited. The GNAS-1 gene encodes for the Gsα (guanine-nucleotide binding) protein. The substitution of arginine into histidine or cysteine results in continuous overactivity of the adenylate cyclase system and unregulated productivity from affected tissues. The abnormalities associated with this syndrome are related to this overactivity. McCune-Albright syndrome results in mosaicism, such that the abnormal gene is present in only a fraction of the patient’s cells. The timing of the mutation determines which organ systems are affected and the severity of the presentation, thus explaining the heterogeneity of these syndromes. In a recent, large collaborative study, investigators were able to identify the Gsα mutation in 43% of patients presenting with at least one sign of McCune-Albright syndrome and in 33% of those presenting with isolated signs of gonadotropin-independent precocious puberty.50 Treatment
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In contrast to central precocious puberty, girls with McCuneAlbright syndrome exhibit a lack of GnRH pulsatility, low gonadotropin levels, and estradiol production from autonomous follicle development. Accordingly, diagnostic GnRH administration results in a prepubertal LH/FSH response (see Fig. 11-4). As would be expected, therapy with GnRH agonists is rarely effective. Hence, treatment protocols for McCune-Albright syndrome are aimed at inhibiting peripheral estradiol production with aromatase inhibitors or blocking the effects at the receptor level with selective estrogen receptor modulators (SERMs). Aromatase inhibitors offer several theoretical benefits for the treatment of McCune-Albright syndrome. Unfortunately, results from studies evaluating testolactone have been inconclusive.51–53 Testolactone is a synthetic antineoplastic agent that also inhibits aromatase activity, thereby lowering estrogen levels. Testolactone may induce regression of breast development and menstruation in the short term; however, the beneficial effect wanes and frequent dosing intervals are often required. Other formulations may someday prove more useful.
It has been suggested that continuous estrogen exposure from a peripheral source may secondarily induce the HPO axis, such that a central component may occur simultaneously.54 These findings may help to explain the lack of therapeutic benefit of aromatase inhibitors in certain patients with McCune-Albright syndrome. Evaluation and management of these complicated patients should then be based on algorithms used for central precocious puberty. The SERM tamoxifen was studied in a prospective, multicenter trial for the 12-month treatment of 25 girls with McCuneAlbright syndrome. This treatment decreased the incidence of vaginal bleeding, and also decreased bone growth velocity and bone maturation.55
Other Causes Other causes of GnRH-independent precocious puberty include adrenal disorders such as congenital adrenal hyperplasia (see Table 11-1). Patients present with heterosexual development, and androgen levels, including 17OH-progesterone, will be elevated. Corticosteroid therapy is the treatment of choice. Primary hypothyroidism, albeit uncommon, may result in ovarian cyst development, resulting in high estradiol levels. This has been hypothesized to be the result of cross-reactivity of high levels of thyroid-stimulating hormone (TSH) with FSH at the level of the ovarian receptors.56
PREMATURE THELARCHE Early breast development in the absence of other signs of sexual maturity is typically a benign, self-limited event. Initial laboratory evaluation will reveal prepubertal gonadotropin levels and normal bone age. GnRH stimulation will result in a predominant FSH response. Continued observation is nonetheless mandatory, and breast development, which may be unilateral or bilateral, will likely regress or may persist until the normal onset of puberty. Parental reassurance is the only recommended therapy.
PREMATURE ADRENARCHE Adult pubic hair growth before age 6 may result from an abnormal adrenal secretory response that promotes androgen production (17-hydroxypregnenolone, DHEA, and DHEA-S). Like premature thelarche, the diagnosis can only be made after longitudinal evaluation, in the absence of other signs of sexual development. Although mild increases in bone age may occur, no treatment is necessary because these children will likely achieve normal adult height.57 A morning 17OH-progesterone level is generally sufficient to rule out nonclassic CAH unless there is significant bone age advance. A corticotropin stimulation test should then be performed. Only patients with conclusively high levels of 17OHprogesterone warrant treatment. In the absence of other pathology, no therapy is indicated.
Premature Adrenarche and Polycystic Ovary Syndrome There is evidence to suggest that girls with premature adrenarche may be at risk for developing polycystic ovary syndrome (PCOS). Known outcomes of this syndrome include obesity, dyslipidemia, hyperinsulinemia, hirsutism, and infertility. A recent randomized
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Chapter 11 Normal Puberty and Pubertal Disorders trial evaluating the effectiveness of metformin therapy in adolescents with a history of precocious pubarche and low birth weight noted significant reversal in dyslipidemia, excess truncal fat, increased levels of IGF-I, and insulin insensitivity compared to controls. Early therapy aimed at improving insulin resistance and reducing percentage of body fat may improve cardiovascular risk later in life.58
DELAYED PUBERTY AND PRIMARY AMENORRHEA Delayed puberty in girls is defined as lack of thelarche by age 13 or when more than 4 years pass between thelarche and menarche. Primary amenorrhea is diagnosed when girls who have developed secondary sexual characteristics do not reach menarche by age 16. Both physical and psychosocial concerns of these patients and their parents must be considered. Most girls with delayed puberty have normal ovaries (eugonadal) and their sexual development is constitutionally delayed. Others are hypogonadal, such that their ovaries do not secrete estrogen appropriately. Hypogonadism can be the result of ovarian failure, termed hypergonadotropic hypogonadism, or occur because normal ovaries are not stimulated to secrete hormones, referred to as hypogonadotropic hypogonadism.
Hypergonadotropic Hypogonadism Hypergonadotropic hypogonadism, often referred to as ovarian failure, is the single most common etiology of pubertal delay. The essential condition required to make this diagnosis is elevated gonadotropins, both FSH and LH. Turner’s syndrome is the most commonly (1:2000 liveborn females) diagnosed condition within this subset. Karyotype may reveal 45,X or a mosaic, which may occur in up to 40% to50% of patients with gonadal dysgenesis. DNA analysis is crucial because the presence of the Y chromosome places patients at risk for gonadal neoplasia such as gonadoblastoma and dysgerminoma. Several forms of primary and secondary ovarian failure with normal sex chromosomes also exist. Pure gonadal dysgenesis, Swyer syndrome, typically presents with delayed puberty. Chemotherapy and/or radiation therapy may result in gonadal dysfunction and delayed development in an otherwise genetically and phenotypically normal female. Other causes of ovarian failure include autoimmune oophoritis, galactosemia, gonadotropin-resistant ovary syndrome, steroidogenesis enzyme deficiency, infection, or gonadotropin receptor gene mutation. Autoimmune disorders associated with hypergonadotropic hypogonadism include Hashimoto’s thyroiditis and Addison’s disease. Patients with 17α-hydroxylase deficiency present with adrenal insufficiency, hypertension, and lack of sex steroids, including androgens. Although rare, patients with gonadotropin-resistant ovary syndrome will have normal appearing ovaries with multiple primordial follicles that do not respond to endogenous or exogenous gonadotropins.
Hypogonadotropic Hypogonadism Hypogonadotropic hypogonadism is diagnosed when the gonadotropins are not elevated in girls with delayed puberty. This
condition results from a failure of the HPO axis and deficiency of GnRH. The most common cause of this is constitutional delay. The diagnosis of constitutional (or physiologic) delayed puberty is one of exclusion. Bone age and height age (age at which height is at the 50th percentile on growth charts) are delayed, unlike hypothyroidism, where bone age is delayed more than height age. Unfortunately, the only way to discern constitutional delay from idiopathic hypogonadotropic hypogonadism is by longitudinal observation. Central etiologies of hypogonadotropic hypogonadism include brain tumors, Kallmann syndrome, hypothyroidism, and chronic disease states (Crohn’s disase, Cushing’s disease, anorexia nervosa, or malnutrition). Pituitary causes are also possible, such as a tumor or gonadotropin insufficiency.
Primary Amenorrhea with Otherwise Normal Sexual Development Genetically normal patients with a normally functioning HPO axis who present with primary amenorrhea typically have anomalies of the genital outflow tract, such as imperforate hymen or vaginal septum (Table 11-3). The classic presentation is cyclic abdominal pain with a tender midline pelvic mass on rectal examination (see Chapters 12 , 14, and 16). One of the most common causes of primary amenorrhea in these patients is Mayer-Rokitansky-Küster-Hauser (MRKH) syndrome. This condition is characterized by a blind vaginal pouch in an otherwise normally sexually developed adolescent and results from the failure of development of the müllerian (paramesonephric) duct system in genotypic females. Androgen insensitivity syndrome is another common cause of primary amenorrhea. Previously termed testicular feminization, this condition is the result of an abnormal androgen receptor. This maternal X-linked recessive disease occurs in individuals with XY
Table 11-3 Causes of Primary Amenorrhea Hypogonadism Hypergonadotropic hypogonadism Abnormal sex chromosomes Turner’s syndrome Normal sex chromosomes 46,XX gonadal dysgenesis 46,XY gonadal dysgenesis Pseudo-ovarian failure Hypogonadotropic hypogonadism Congenital abnormalities GnRH deficiency Gene mutations Constitutional delay Acquired abnormalities Endocrine disorders Pituitary tumors Systemic disorders Eugonadism Anatomic abnormalities Congenital absence of uterus and vagina Imperforate hymen Transverse vaginal septum Intersex disorders Androgen insensitivity Polycystic ovary syndrome Data from Timmreck LS, Reindollar RH. Contemporary issues in primary amenorrhea. Obstet Gynecol Clin North Am 30:287-302, 2003
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Section 2 Pediatric and Adolescent Disorders genotypes and normal but partially or completely undescended testicles that produce testosterone (see Chapter 16). Because of the abnormal androgen receptors, high levels of circulating testosterone result in appropriately timed puberty in females who appear phenotypically normal. A harbinger is sparse or absent pubic hair. Primary amenorrhea or delayed menarche is frequently associated with hyperandrogenemia, secondary to either PCOS or adult-onset congenital adrenal hyperplasia. These patients have otherwise normal puberty but will also present with signs of excess androgen ranging from hirsutism and acne to virilization.
Evaluation A complete evaluation should be undertaken for any adolescent who meets the standard criteria for delayed puberty or primary amenorrhea: • Lack of any breast development by age 13 • More than 5 years between thelarche and menarche, if it occurs before age 10 • No menses by age 15 Both physical and psychosocial concerns of these patients and their parents must be considered.
History Extensive neonatal and family history, including ages of pubertal development and attainment of final height extending to members beyond the nuclear family, is helpful. History pertinent to information of prior exposure to exogenous steroid hormones or chemotherapy must also be elicited. Review of systems to evaluate for chronic illnesses and pattern of exercise and diet may uncover the diagnosis.
Physical Examination
166
Physician examination and height and weight plotted on a growth chart should be completed as well as blood pressure, thyroid examination, Tanner staging, and abdominal examination. A complete neurologic evaluation, including assessing the ability to smell, should also be performed. Patients with hypergonadotropic hypogonadism often present short in stature. Patients with Turner’s syndrome (45,XO), the most common presentation of hypergonadotropic hypogonadism, may present during infancy with lymphedema or during childhood with typical features such as short stature, webbed neck, and shortened fourth metacarpals. Cardiovascular anomalies and renal abnormalities, such as coarctation of the aorta, bicuspid aortic valves, and horseshoe kidney, can be determined with imaging studies. Patients with mixed gonadal dysgenesis (mosaic XY/XO) may present phenotypically similar to those with Turner’s syndrome; however, virilization or ambiguous genitalia may also be evident in the presence of the Y chromosome. Patients with 46,XX complete gonadal dysgenesis are normal to tall in stature and are commonly phenotypically female. Sexual infantilism with lack of müllerian structures and 46,XY karyotype is consistent with Swyer syndrome. Hypogonadotropic hypogonadism can be seen in adolescents who are extremely athletic or malnourished. Minimal body fat
from either cause is associated with reversible hypothalamic dysfunction. Patients with CNS tumors may present with persistent headaches or visual field defects. Marked centripetal obesity and moon facies are typical of Cushing’s syndrome. Anosmia along with hypothalamic hypogonadism is consistent with the diagnosis of Kallmann’s syndrome (isolated GnRH deficiency). A patient with a prolactinoma may present with hyperprolactinemia and galactorrhea. Adolescents with primary amenorrhea who have normal development of other secondary sexual characteristics are usually of normal stature. Pelvic or recto-abdominal examination is performed in these patients to exclude anatomic abnormalities of the reproductive tract. Examples include vaginal septum and the blind vaginal pouch associated with MRKH and androgen insensitivity syndrome.
Laboratory Evaluation Initial assessment of the adolescent presenting with delayed sexual development should include a complete blood count, as well as TSH, thyrotropin, FSH, LH, and prolactin levels. A chemistry panel will be helpful if chronic illness is suspected. If FSH and LH are normal or low, a GnRH stimulation test will be useful. If FSH and LH are elevated indicating ovarian failure, a karyotype should be obtained. Regardless of gonadotropin levels, a karyotype should be considered in short girls with delayed puberty, because many adolescents with chromosomal abnormalities will not have classic clinical features of disorders such as Turner’s syndrome.
Imaging Bone age is defined as the age consistent with the degree of bone ossification of a child and is determined by taking an x-ray of the left wrist and hand. Bone age more strongly correlates with sexual development than chronological age. This measurement will be normal to delayed in most patients with delayed puberty arising from a pathologic cause. Stature, consequently, will be decreased in patients with hypergonadotropic hypogonadism with the exception of pure gonadal dysgenesis (46,XX). If gonadotropin levels are low with delayed puberty, a central cause must be determined. Likewise, an elevated prolactin level suggests a pituitary or hypothalamic problem. In these cases, MRI scan of the brain and pituitary gland is indicated to exclude abnormality of the hypothalamic-pituitary axis such as pituitary or hypothalamic tumors. Adolescents with primary amenorrhea but otherwise normal sexual development require pelvic ultrasound to evaluate the internal reproductive organs and detect the presence of a fluid collection consistent with hematocolpos related to a vaginal septum. Abdominal and pelvic MRI is helpful in evaluating for renal or skeletal anomalies in patients with vaginal agenesis.
Treatment of Delayed Puberty Specific Therapy
Therapy for hypogonadotropic disorders is focused at treating the primary etiology whenever possible. If an intracranial lesion compresses the pituitary stalk, surgical therapy is indicated. If prolactinoma is the cause, bromocriptine or cabergoline becomes the first line of therapy. Medical therapy generally restores
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Chapter 11 Normal Puberty and Pubertal Disorders menses and fertility, and although surgical treatment may portend good results initially, there is a high incidence of recurring hyperprolactinemia. Surgery may therefore be postponed unless the condition is refractory to medical management. Treatment for competitive athletes and patients with anorexia nervosa becomes somewhat more challenging. Because total body fat of at least 12% to 14% has been associated with return of menses, many clinicians feel that patients should be encouraged to change their lifestyle and improve their diet before introducing pharmaceutical management. Whereas patients with idiopathic or irreversible gonadal failure who have not demonstrated sexual development begin therapy at age 14 to 15, therapy may be initiated later for these patients.
Patients and their parents should be educated about their condition and encouraged to ask questions. Addressing future issues such as treatment of infertility and prevention of osteoporosis early in the course of treatment may allow for gradual acceptance. Referral to support groups often proves beneficial because teens can discuss their concerns with those who have experienced the same problem. Girls with delayed puberty inevitably feel different and underdeveloped from their peers, which may result in social isolation and pathologic dependency on their parents. The role of the clinician, therefore, must expand beyond the medical scope of the specific problem and consider the long-term sequelae of the problem at hand.
Estrogen Therapy
CONCLUSIONS
If the cause of delayed puberty is determined to be irreversible or idiopathic (i.e., constitutional delay), sex steroid hormone replacement is indicated. The goal shared by both patient and physician involves induction of breast development, bone growth, and menses. Hormone replacement for patients with ovarian failure is important not only to induce pubertal development, but also to decrease the risk of subsequent osteoporosis and cardiovascular disease due to the prolonged hypoestrogenic state. Timing is quite important when starting hormone replacement. In most instances, therapy is initiated when patients present with delayed puberty during their early teenage years. However, some Turner’s syndrome patients will be referred for evaluation during childhood. If these patients begin estrogen therapy too early, their potential growth may be limited by epiphyseal closure. Hormone replacement for treatment of delayed puberty is begun with low-dose estrogens, typically 0.3 mg conjugated estrogens for 6 to 12 months. The main goal is to induce normal breast development, because too high of an estrogen dose can result in the development of tuberous breasts.59 Subsequent goals include regulation of menses and maintenance of bone mass. This can be achieved by increasing the dosage of estrogen slowly after the first year until menstruation occurs. Progestin therapy (e.g., medroxyprogesterone acetate [5–10 mg]) is initiated approximately 3 months after the increase in dosage of estrogen, typically when breakthrough bleeding occurs. The most common formulation includes continuous estrogen therapy with sequential progestins given orally in the latter part of the cycle to create regular menses. Alternative forms include transdermal estrogen replacement and micronized progestins that have less negative impact on lipid profiles. Gonadotropins have also been used to induce ovulation, but are costly and more difficult to administer, especially in an adolescent patient population.
A perceptive and knowledgeable clinician can successfully treat many of the physical and hormonal problems associated with both precocious and delayed puberty. Medical conditions associated with either of these problems can put girls at risk for decreased adult height and increased emotional difficulties. Early medical and psychological intervention can often help these girls attain normal adult height and avoid long-term adverse social consequences.
PEARLS ●
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Sexual maturation begins with the activation of the hypothalamic pituitary axis The two primary controls are the intrinsic CNS inhibition via GABA and negative feedback system driven by ovarian steroid hormones. The first event of puberty is accelerated growth velocity, followed by thelarche, adrenarche, the growth spurt and then menarche. Initiation of puberty before age 8 is considered precocious, although in most circumstances observation rather than investigation is all that is required. Obtaining a bone age is the first step in the investigation of precocious puberty Central precocious puberty is treated with a GnRH agonist while peripheral precocious puberty is treated with agents that block the effects of estrogen. The most frequent causes of primary amenorrhea are gonadal dysgenesis and mullerian agenesis. A confirmed elevated serum FSH indicates ovarian failure and mandates a karyotype
Psychological Implications The ability to establish open channels of communication is extremely important in treating patients with delayed puberty.
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1. Emans SJ, Laufer MR, Goldstein DP (eds): Pediatric and Adolescent Gynecology: The Physiology of Puberty. Baltimore, Lippincott Williams & Wilkins, 1998, pp 109–140. 2. Kaplan SL, Grumbach MM, Aubert ML: The ontogenesis of pituitary hormones and hypothalamic factors in the human fetus: Maturation of central nervous system regulation of anterior pituitary function. Recent Prog Hor Res 32:161, 1976. 3. Grumbach MM, Kaplan SL: The neuroendocrinology of human puberty: An ontogenetic perspective. In Grumbach MM, Kaplan SL, Sizoneko PC, Aubert ML (eds): Control of the Onset of Puberty. Baltimore, Williams & Wilkins, 1990, pp 1–68. 4. Mitsushima D, Hei DL, Terasawa E: γ-Aminobutyric acid is an inhibitory neurotransmitter restricting release of luteinizing hormone-releasing hormone before the onset of puberty. Proc Natl Acad Sci USA 91:395–399, 1994. 5. Tapanainen J, Koivisto M, Vijko R, et al: Enhanced activity of the pituitary-gonadal axis in premature human infants. J Clin Endocrinol Metab 52:235–238, 1981. 6. Roth JC, Kelch RP, Kaplan SL, et al: FSH and LH response to luteinizing hormone-releasing factor in prepubertal and pubertal children, adult males and patients with hypogonadotropic and hypergonadotropic hypogonadism. J Clin Endocrinol Metab 37:680, 1973. 7. Boyar R, Finkelstein J, Roffwarg H, et al: Synchronization of augmented luteinizing hormone secretion with sleep during puberty. NEJM 287:582, 1972. 8. Landy H, Boepple PA, Mansfield MJ, et al: Sleep modulation of neuroendocrine function: Developmental changes in gonadotropinreleasing hormone secretion during sexual maturation. Pediatr Res 28:213–217, 1990. 9. Yen SS, Apter D, Butzow T, et al: Gonadotropin releasing hormone pulse generator activity before and during sexual maturation in girls: New insights. Hum Reprod 8(Suppl 2):66–71, 1993. 10. Apter D, Bhtzow TL, Laughlin GA, et al: Gonadotropin releasing hormone pulse generator activity before and during sexual maturation in girls: New insights. Hum Reprod 8:66, 1993. 11. Frisch RE, Revelle R: Height and weight at menarche and a hypothesis of critical body weights and adolescent events. Science 169:397, 1970. 12. Warren MP: The effects of exercise on pubertal progression and reproductive function in girls. J Clin Endocrinol Metab 50:1150, 1980. 13. Penny R, Goldstein IP, Frasier SD: Gonadotropin secretion and body composition. Pediatrics 61:294, 1978: 14. Apter D: Leptin and puberty. Curr Opin Endocrinol Diabet 7:57–64, 2000. 15. Farooqi IS, Jebb SA, Langmack G, et al: Effects of recombinant leptin therapy in a child with congenital leptin deficiency. NEJM 341:879–884, 1999. 16. Sahu A, Phelps CP, White JD, et al: Steroidal regulation of hypothalamic neuropeptide Y release and gene expression. Endocrinology 130:3331, 1992. 17. Kaye WH, Berrettini W, Gwirtsman H, et al: Altered cerebrospinal fluid of neuropeptide Y and peptide YY immunoreactivity in anorexia and bulimia nervosa. Arch Gen Psychiatry 47:548, 1990. 18. Marshall W, Tanner J: Variations in the pattern of pubertal changes in girls. Arch Dis Child 44:291, 1969. 19. Abbassi V: Growth and normal puberty. Pediatrics 102:507, 1998. 20. Kaplowitz PB, Oberfield SE: Reexamination of the age limit for defining when puberty is precocious in girls in the United States: Implications for evaluation and treatment. Drug and Therapeutics and Executive Committees of the Lawson Wilkins Pediatric Endocrine Society. Pediatrics 104:936–941, 1999. 21. He Q, Karlberg J: BMI in childhood and its association with height gain, timing of puberty and final height. Pediatr Res 49:244–251, 2001. 22. Mansfield MJ, Rudlin CR, Crigler Jr JF, et al: Changes in growth and serum growth hormone and plasma somatomedin-C levels during suppression of gonadal sex steroid secretion in girls with precocious puberty. J Clin Endocrinol Metab 66:3, 1988.
23. Wyshak G, Frisch RE: Evidence for a secular trend in age of menarche. NEJM 306:1033, 1982. 24. Herman-Giddens ME, Slora EJ, Wasserman RC, et al: Secondary sexual characteristics and menses in young girls seen in office practice: A study from the Pediatric Research in Office Settings network. Pediatrics 99:505–512, 1997. 25. MacMahon B: National Health Examination Survey: Age at menarche. National Center for Health Statistics. DHEW publication (HRA). 12:74–1615, 1973. 26. Angold A, Worthman CW: Puberty onset of gender differences in rates of depression: A developmental, epidemiologic and neuroendocrine perspective. J Affect Disord 29:145, 1993. 27. Sigurjonsdottir TJ, Hayles AB: Precocious puberty. A report of 96 cases. Am J Dis Child 115:304–321, 1968. 28. Cutler GB: Precocious puberty. In Hurst JW (ed): Medicine for the Practicing Physician, 2nd ed. Woburn, Mass., Butterworth, 1988, pp 526–530. 29. Cisternimo M, Arrigo T, Pasquino AM, et al: Etiology and age incidence of precocious puberty in girls: A multicentric study. J Pediatr Endocrinol 13(Suppl I):695–701, 2000. 30. Chalumeau M, Chemaitilly W, Trivin C, et al: Central precocious puberty in girls: An evidence-based diagnosis tree to predict central nervous system abnormalities. Pediatrics 109:61, 2002. 31. de Vries L, Kauschansky A, Shohat M, et al: Familial central precocious puberty suggests autosomal dominant inheritance. J Clin Endocrinol Metab 89:198–200, 2004. 32. Partsch CJ, Sippell WG: Treatment of central precocious puberty. Best Pract Res Clin Endocrinol Metab 16:165–189, 2002. 33. Bayley N, Pinneau SR: Tables for predicting adult height from skeletal age: Revised for use with the Greulich-Pyle hand standards. J Pediatr 40:423–441, 1952. 34. Fontoura M, Brauner R, Prevot C, et al: Precocious puberty in girls: Early diagnosis of a slowly progressing variant. Arch Dis Child 64:1170–1176, 1989. 35. Graber JA, Seeley JR, Brooks-Gunn J, Lewinsohn PM: Is pubertal timing associated with psychopathology in young adulthood? J Am Acad Child Adolesc Psychiatry 43:6718–6726, 2004. 36. Waylen A, Wolke D: Sex ‘n’ drugs ‘n’ rock ‘n’ roll: The meaning and social consequences of pubertal timing. Eur J Endocrinol 151(Suppl 3):U151–U159, 2004. 37. Sorgo W, Kiraly E, Homoki J, et al: The effects of cyproterone acetate on statural growth in children with precocious puberty. Acta Endocrinol 115:44–56, 1987. 38. Comite F, Cutler Jr GB, Rivier J, et al: Short-term treatment of idiopathic precocious puberty with a long-acting analogue of lutenizing hormone-releasing hormone. NEJM 305:1546–1550, 1981. 39. Kauli R, Galatzer A, Kornreich L, et al: Final height of girls with central precocious puberty, untreated versus treated with cyproterone acetate or GnRH analogue. A comparative study with re-evaluation of predictions by the Bayley-Pinneau method. Horm Res 47:54–61, 1997. 40. Bouvattier C, Coste J, Rodrigue D, et al: Lack of effect of GnRH agonists on final height in girls with advanced puberty: A randomized long-term pilot study. J Clin Endocrinol Metab 84:3575–3378, 1999. 41. Cassio A, Cacciari E, Balsamo A, et al: Randomised trial of LHRH analogue treatment on final height in girls with onset of puberty aged 7.7–8.5 years. Arch Dis Child 81:329–332, 1999. 42. Weise M, Armando F, Barnes KM, et al: Determinants of growth during gonadotropin-releasing hormone analog therapy for precocious puberty. J Clin Endocrinol Metab 89:103–107, 2004. 43. Oerter KE, Manasco P, Barnes KM, et al: Adult height in precocious puberty after long-term treatment with deslorelin. J Clin Endocrinol Metab 73:1235–1240, 1991. 44. Kauli R, Galatzer A, Kornreich L, et al: Final height of girls with central precocious puberty, untreated versus treated with cyproterone acetate or GnRH analogue. A comparative study with re-evaluation of predictions by Bayley-Pinneau method. Horm Res 47:54–61, 1997.
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Chapter 11 Normal Puberty and Pubertal Disorders 45. Brauner R, Adan L, Malandry F, et al: Adult height in girls with idiopathic true precocious puberty. J Clin Encodrinol Metab 79:415–420, 1994. 46. Adan L, Chemaitilly W, Trivin C, et al: Factors predicting adult height in girls with idiopathic central precocious puberty: Implications for treatment. Clin Endocrinol 56:297–302, 2002. 47. Khadilkar VV, Khadilkar VV, Maskati GB: Growth hormone and GnRHα combination therapy in the management of precocious puberty. Indian Pediatr 42:157–160, 2005. 48. Schultz KA, Sencer SF, Messinger Y, et al: Pediatric ovarian tumors: A review of 67 cases. Pediatr Blood Cancer 44:2167–2173, 2005. 49. Lumbroso S, Paris F, Sultan C. McCune-Albright syndrome: Molecular genetics. J Pediatr Endocrinol Metab 15(Suppl 3):875–882, 2002. 50. Lumbroso S, Paris F, Sultan C: Activating Gsα mutations: Analysis of 113 patients with signs of McCune-Albright syndrome—a European Collaboarative Study. J Clin Endocrinol Metab 89:2107–2113, 2004. 51. Roth C, Freiberg C, Zappel H, Albers N: Effective aromatase inhibition by anastrozole in a patient with gonadotropin-independent precocious puberty in McCune-Albright syndrome. J Pediatr Endocrinol Metab 3(Suppl 15):945–948, 2002. 52. Nunez SB, Calis K, Cutler Jr GB, et al: Lack of efficacy of fadrozole in treating precocious puberty in girls with the McCune-Albright syndrome. J Clin Endocrinol Metab 88:5730–5733, 2003.
53. Feuillan PP, Jones J, Cutler Jr GB: Long-term testolactone therapy for precocious puberty in girls with the McCune-Albright syndrome. J Clin Endocrinol Metab 77:647–651, 1993. 54. Speroff L, Glass RH, Kase NG (eds): Abnormal puberty and growth problems. In Clinical Gynecologic Endocrinology and Infertility, 6th ed. Baltimore, Lippincott Williams & Wilkins, 1999, pp 381–420. 55. Eugster EA, Rubin SD, Reiter EO, et al: Tamoxifen treatment for precocious puberty in McCune-Albright syndrome: A multicenter trial. J Pediatr 143:9–10, 2003. 56. Anasti JN, Flack MR, Froehlich J, et al: A potential novel mechanism for precocious puberty in juvenile hypothyroidism. J Clin Endocrinol Metab 80:276, 1995. 57. Ibáñez L, Virdis R, Potau N, et al: Natural history of premature pubarche: An auxological study. J Clin Endocrinol Metab 74:254, 1992. 58. Ibáñez L, Ferrer A, Ong K, et al: Insulin sensitization early after menarche prevents progression from precocious pubarche to polycystic ovarian syndrome. J Pediatr 144:23–29, 2004. 59. Griffin JE: Hormonal replacement therapy at the time of expected puberty in patients with gonadal failure. Endocrinologist 13:3211–3213, 2003.
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12
Congenital Anomalies of the Female Reproductive Tract Lawrence S. Amesse and Teresa Pfaff-Amesse
INTRODUCTION Congenital anomalies of the female reproductive tract are among the most fascinating disorders encountered by the obstetrician and the gynecologist. Aberrations in the development of the müllerian ducts and ovarian anlage result in abnormalities of internal reproductive structures as well as ambiguity of the external genitalia. These anomalies are often caused by errors in organogenesis, but other etiologies, including deficiencies in steroidogenesis, receptor defects, and genetic abnormalities, are also involved. Most müllerian duct abnormalities are associated with functioning ovaries and age-appropriate external genitalia. Individuals with müllerian duct defects often present during adolescence as normal females with appropriate primary and secondary sexual characteristics. However, their internal structures will be abnormal on further investigation. In contrast, when congenital anomalies involve either ovaries or external genitalia, the müllerian-derived structures are often normal. In these cases, identifiable aberrations of the external genitalia are often noted in early infancy, with delays in secondary sexual characteristics occurring in later life. Specific congenital anomalies of the reproductive tract can be difficult to diagnose because of the wide variety of clinical presentations. Once an accurate diagnosis is rendered, many treatment options exist and are often individualized for a given malformation. For infants born with ambiguous genitalia, a multidisciplinary approach is often necessary. Refinements in surgical and medical techniques have enabled many women with these disorders to have normal satisfying sexual relations. Advances in reproductive technologies have resulted in improved fertility and obstetrical outcomes. Indeed, assisted reproductive technologies now allow many women with congenital anomalies of the reproductive tract to conceive and deliver healthy babies.1 This chapter describes the normal embryology of the female reproductive system, followed by a discussion of the pathogenesis and diagnostic methods used to identify the various abnormalities of these structures. Additionally, a scheme used for the evaluation of patients with ambiguous genitalia is discussed and counseling is addressed.
EMBRYOLOGY OF THE FEMALE REPRODUCTIVE TRACT In the normal female embryo, a series of well-orchestrated, complex interactions is required for proper differentiation of the müllerian ducts and urogenital sinus. Although originating from different germ layers, the fates of the müllerian ducts
(mesoderm) and urogenital sinus (endoderm) are interconnected as they differentiate to form the female reproductive tract. The müllerian ducts are the primordial anlage of the internal female reproductive organs and differentiate to form the fallopian tubes, uterus, cervix, and superior aspect of the vagina.1 When the dynamic processes of differentiation, migration, fusion, and canalization are interrupted, a wide spectrum of congenital anomalies of the reproductive tract can result. The anatomic malformations can range from agenesis of the uterus and vagina to duplication of the reproductive organs. Disruption of local mesoderm development and its contiguous somites can account for associated urologic and axial skeletal abnormalities, respectively, that quite often coexist. The ovaries develop initially as indifferent gonads and are derived from three sources: the mesothelium, underlying mesenchyme, and primordial germ cells. Under the influence of both X chromosomes and autosomes, the indifferent gonads differentiate into ovaries beginning at approximately week 10 of embryogenesis; at week 16, primary follicles begin to develop. Development of external genitalia begins at week 4 with proliferating mesenchyme producing a genital tubercle that elongates to produce the phallus. The urogenital folds will eventually differentiate to form the labia minora and surround the phallus.
Development of the Fallopian Tubes, Uterus, and Uterine Cervix Two sets of paired genital ducts, paramesonephric (müllerian) and mesonephric (Wolffian), are present in female and male embryos at 6 weeks of development (Fig. 12-1). We use the two terms that refer to each duct somewhat interchangeably. For example, although most embryology books use the term paramesonephric duct, most clinicians use the term müllerian. Development of the mesonephric ducts precedes that of the paramesonephric ducts, and for a short period, the mesonephric ducts drain the contents of the primitive mesonephric kidney into the cloaca.2 A key gene for the development of paramesonephric and mesonephric ducts is PAX2. Mutations in this gene will result in impaired duct and renal development in both sexes. In the female, the mesonephric ducts will degenerate in the absence of testosterone, and the paramesonephric ducts develop because of the absence of anti-müllerian (AMH).2–4 At the same time, the paramesonephric ducts, which originated as longitudinal invaginations of coelomic epithelium, begin to elongate bidirectionally along the anterolateral aspects of the gonads.2 The regressing mesonephric ducts provide an ideal template for the elongating paramesonephric ducts. This primordial connection
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Mesonephros Mesonephric nephrons Paramesonephric (Mullerian) duct Proliferating coelom epithelium Mesonephric duct Gubernaculum
Urogenital sinus
Tunica albuginea Appendix testis
Appendix epididymis
Testis
Uterine tube
Efferent ductules
Ovary
Epididymis Vas deferens Gubernaculum ovarii
Seminal vesicle
Uterus
Gartner's duct Utricle of prostate
Cervix
Gubernaculum testis Figure 12-1
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Embryologic development of the male and female ducts.
explains the frequent associations seen later between paramesonephric duct anomalies and urinary system malformations. In the male the paramesonephric ducts will regress under the influence of antimüllerian hormone secreted by the Sertoli cells of the testes. Persistence of the paramesonephric ducts in the male is seen with a mutation of the gene coding for antimüllerian hormone or its receptor. As the paramesonephric ducts elongate at week 9, three recognizable regions can be identified: the cranial, horizontal, and caudal aspects. Each of these regions will have a distinct fate.2,5 The funnel-shaped cranial regions open directly into the early peritoneal cavity and will form the fimbria of the fallopian tubes. The paramesonephric ducts at this level are lateral to the mesonephric ducts (see Fig. 12-1). The paired horizontal segments migrate lateral to the mesonephric ducts, then cross ventrally and extend caudomedially to form the remainder of the fallopian tubes. The caudal regions come into contact with their contralateral component at the median plane in the future pelvis and fuse, forming a single Y-shaped tubular structure known as the uterovaginal primordium.
The uterovaginal primordium consists of a uterine and vaginal region.2,5 The uterine region gives rise to the uterus; correspondingly, the vaginal component will develop into the superior aspect of the vagina.2,3,5 The uterus has a bicornuate appearance at this stage, but its anatomic configuration will continue to develop through the processes of fusion and subsequent canalization. Uterine septum canalization or regression is mediated by apoptosis, which is regulated by the bcl-2 gene.6 Fusion was thought to occur from a caudal to cranial direction. However, anomalies found in postnatal life, such as a double cervix and vagina but a normal uterus, suggests that fusion may occur initially at the level of the internal uterine isthmus and then proceed in both directions.3 By week 12, the uterine fundus assumes its mature shape. The uterine endometrium is derived from the lining of the fused paramesonephric (müllerian) ducts, and the endometrial stroma and myometrium are derived from adjacent mesenchyme.4,7 This entire process is completed by week 22 of development and results in a uterine cervix and uterus with a single uterine cavity.2
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Chapter 12 Congenital Anomalies of the Female Reproductive Tract Development of the Vagina and Hymen Normal vaginal development requires the fusion of two different embryologic structures, the mesodermal paramesonephric (müllerian) ducts and the endodermal urogenital sinus. After formation of the Y-shaped uterovaginal primordium, the caudal tip of the uterovaginal primordium inserts into the dorsal wall of the urogenital sinus (see Fig. 12-1). This event creates an elevation called the müllerian or sinus tubercle. The sinus tubercle induces the formation of the sinovaginal bulbs at its distal aspect. As paired endodermal evaginations, the sinovaginal bulbs extend as a solid core from the urogenital sinus to the caudal aspect of the uterovaginal primordium and then fuse to form the vaginal plate.2,7,8 The vaginal plate and the sinovaginal bulbs restructure the urogenital sinus from its original long, tubular structure into a flat vestibule. This restructuring is responsible for positioning the female urethra at the primitive perineum. Meanwhile, the vaginal plate canalizes caudal to cephalad; when this process is complete at week 20, the vaginal canal is formed. The precise boundary between the uterovaginal primordium and urogenital sinus, as well as their individual contributions to the vagina, has not been established. Some authorities maintain that the superior one third of the vaginal epithelium is derived from the uterovaginal primordium and the inferior two thirds from the uterogenital sinus. However, most other experts consider the entire vaginal lining to be derived from the vaginal plate of the uterogenital sinus.2,7 The vaginal fibromuscular wall develops from the surrounding mesenchyme. The hymen is formed by expansion of the caudal aspect of the vagina with the subsequent invagination of the posterior wall of the urogenital sinus.2,7 It serves to separate the vaginal lumen from the urogenital sinus cavity until late in fetal development. It ruptures perinatally, with the remnants remaining as a thin mucous membrane.8
Development of the Ovary Chromosomal and genetic sex is determined at fertilization when the X ovum is fertilized by either an X-bearing or Ybearing sperm. The XX or XY chromosomal complement of the embryo provides the genes coding for a group of transcription factors—Wilms’ tumor suppressor gene (WT1), DAX1, and steroidogenic factor (SF-1)—that orchestrate gonadal differentiation into either an ovary or testis. WT1 is also important for renal development. Renal and gonadal agenesis will occur with a mutation in the WT1 gene. SF1 and DAX1 gene mutations are associated with gonadal dysgenesis and impaired development of the adrenal cortex. DAX1, an X-linked molecule, suppresses testicular differentiation. Therefore, patients with a mosaic karyotype such as 45,XO/46,XY may have sufficient expression of DAX1 to suppress testicular development. The same concept applies to XXY Klinefelter’s syndrome. Sex determination of the gonads depends on a number of complex molecular events that direct the interactions of the genes encoding these factors.9 The key gene that determines testicular differentiation is SRY (sex-determining region Y), which is located on the distal short arm of the Y chromosome. The absence of a functional SRY and associated gene cascade results in gonads that differentiate into ovaries. The SRY homeobox 9 (SOX9) gene expression is important for testes development, and its deficiency is
also associated with gonadal dysgenesis. The SOX9 gene is involved in the activation of antimüllerian hormone. Just as the Y chromosome influences the development of the male gonad and phenotype, the X chromosome similarly influences ovarian differentiation and phenotype. The presence of two X chromosomes is crucial to maintenance of normal ovarian function after differentiation. Ovaries of 45,X females demonstrate accelerated oocyte atresia.10 Autosomal genes also influence ovarian development.11 The bipotential or indifferent gonads are identical in the male and female until week 7 of development. During week 5, the mesothelium (mesothelial epithelium from the posterior abdominal wall) and underlying mesenchyme (embryonic connective tissue) near the medial aspect of the mesonephros begin to proliferate, producing the urogenital ridges, which will become the gonad. The primordial germ cells begin to migrate from the base of the allantois, along the dorsal mesentery of the hindgut, to the urogenital ridges. These cells can be identified because they stain with alkaline phosphatase. Mitosis of germ cells occurs all during the migration to the urogenital ridge. In the male this process of mitosis arrests and meiosis does not occur until after birth. In the female, the germ cells enter meiosis and arrest at prophase. By week 6, the primordial germ cells have integrated into the mesenchyme to become part of the primary sex cords. As the primary sex cords regress, the primordial germ cells then become incorporated into the secondary sex cords, which connect to the ovarian epithelium. At week 12, the ovarian cortex can be identified. Approximately 1 week later, the secondary cords fragment, leaving the primordial follicles.10 The primordial follicle is composed of a primordial germ cell surrounded by one layer of sex cord-derived follicular cells; it is now known as the oogonium. The oogonia undergo active mitosis and initiate meiosis during fetal development. Many degenerate before birth, and only about 2 million will remain after birth; they will enlarge to become primary oocytes.
Development of the External Female Genitalia The external genitalia of female and male are similar at the indifferent stage of development between weeks 4 and 7 (Fig. 12-2). Distinguishing sexual characteristics begin to appear at week 9, although full differentiation is not achieved until week 12.2 Mesenchyme at the cranial aspect of the cloacal membrane proliferates, forming the genital tubercle. The genital tubercle elongates to form the phallus and later, the clitoris. The genital folds and the labioscrotal swellings develop bilaterally along the cloacal membrane. At the completion of week 6, the urorectal septum fuses with the cloacal membrane, dividing the membrane into anal (dorsal) and urogenital (ventral) aspects.2,8 The urogenital membrane lies in the floor of the urogenital groove and is bound by the genital folds. Approximately 1 week later, the membranes rupture to form the anus and urogenital orifices, respectively. The urogenital orifice in the female is the primordial urethra and vaginal vestibule. The genital folds meet posteriorly, fuse, and form the labia minora frenulum. Their unfused anterior counterparts become the labia minora (minus) proper. The labioscrotal folds also fuse posteriorly and form the posterior labial commissure.2 When they fuse anteriorly, the anterior labial commissure and mons
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Section 2 Pediatric and Adolescent Disorders Umbilical cord Early bladder
Allanto-enteric diverticulum Genital tubercle Endodermal cloaca
Cloacal membrane
Tail
Urogenital sinus
Hindgut
Genital tubercle Genital fold Urogenital orifice
Labioscrotal swelling
Anal orifice and tubercles
Glans penis
Glans clitoris Urethral groove Urethral orifice
Genital fold Vagina
Scrotal Labial swelling swelling Anus
Glans penis
Glans clitoris
Urethral orifice Fused genital folds Vestibule Labium majus Median raphe
Labium minus Scrotum Anus
174
Figure 12-2 Embryologic development of the external genitalia from an indifferent stage.
pubis are formed. However, most of the labioscrotal folds remain unfused and form the labia majora.
CLASSIFICATION OF CONGENITAL ANOMALIES OF THE INTERNAL REPRODUCTIVE TRACT Müllerian anomalies have been reported dating as far back as the 16th century.12 The epidemiology of these anomalies has been vastly outpaced by the remarkable technical achievements used in their diagnosis and treatment. The actual incidences of these anomalies are not well understood. Indeed, reports widely vary, with most authors reporting an incidence ranging from 1:200 to 1:600 in fertile women.13–15 Most structural anomalies of the internal reproductive tract are a consequence of arrests at specific developmental stages. Although the definitive etiology is often elusive, some genetic, intrauterine, and extrauterine factors, as well as teratogens, such as diethylstilbestrol (DES) and thalidomide, have been implicated. The genetics of various congenital anomalies of the reproductive tract are quite complex and beyond the scope of this chapter. Briefly, most cases occur sporadically. In familial cases, many anomalies appear to be multifactorial. Associations with other modes of inheritance also exist and include autosomal dominant and autosomal recessive patterns of inheritance as well as X-linked disorders. Müllerian anomalies can also represent a component of a multiple malformation syndrome.5,16,17, Müllerian defects are associated with a higher incidence of other congenital anomalies, most notably those of the urinary tract (20% to 25%), gastrointestinal tract (12%), musculoskeletal system (10% to 12%), and heart, eye, and ear (6%). As many as 80% of patients with uterus didelphys and unicornuate uterus have associated renal agenesis because of the intimate association of development between the mesonephric and paramesonephric (müllerian) duct systems.
CLASSIFICATION SYSTEM FOR REPRODUCTIVE TRACT CONGENITAL ANOMALIES In 1988, the American Society for Reproductive Medicine (ASRM), formerly known as the American Fertility Society (AFS), published their classification scheme for female reproductive tract anomalies (Fig. 12-3).18 Their classification represents the most widely accepted method of categorizing these abnormalities and has the major advantages of allowing for standardization of reporting methods and providing a template for long-term studies of reproductive outcomes for each anomaly. The system is organized into seven classes according to the major developmental failure and separates the defects into groups having similar clinical manifestations. It also includes a class characterizing uterine abnormalities related to in utero DES exposure. Although vaginal anomalies are not included, the scheme allows for their incorporation.
Class I: Agenesis or Hypoplasia: Segmental or Complete Agenesis or hypoplasia may involve the vagina, cervix, fundus, fallopian tubes, and/or any combination. The Mayer-Rokitansky-
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Chapter 12 Congenital Anomalies of the Female Reproductive Tract
Patient's Name G
Age
Chart#
Date P
Sp Ab
VTP
Ectopic
Infertile Yes
No
Other Significant History (i.e. surgery, infection,etc.) HSG
Sonography I. Hypoplasis/Agenesis
Photography
Laparoscopy
b. cervical
a. vaginal*
a. communicating b. noncommunicating
c. fundal
Laparotomy IlI. Didelphus
II. Unicornuate
d. tubal e. combined V. Septate
a. complete**
c. no cavity
lV. Bicornuate
d. no horn
a. complete
b. partial
VIl. DES Drug Related
VI. Arcuate
b. partial
*Uterus may be normal or take a variety of abnormal forms. **May have two distinct cervices.
Type of Anomaly Class I
Class V
Class II
Class VI
Class III
Class VII
Additional Findings:
Vagina:
Class IV
Cervix:
Treatment (Surgical Procedures)
Tubes: Right
Left
Kidneys: Right
Left
Prognosis for Conception & Subsequent Viable Infant* Excellent (> 75%)
L
Drawing
R
Good (50-75%) Fair (25-50%) Poor (< 25%) *Based upon physician's judgment. Recommended Followup Treatments:
Figure 12-3 1998.)
Diagram from the American Fertility Society Classification of Müllerian Abnormalities (American Fertility Society, Fertil Steril 49:944–955,
Küster-Hauser syndrome is the most common example in this category.
Class II: Unicornuate Uterus, with or without Rudimentary Horn When a rudimentary horn is present, the unicornuate uterus is divided into either communicating or noncommunicating groups. Communicating designates actual continuity of the horn with the main uterine cavity, and noncommunicating designates no communication with the uterine cavity. Noncommunicating
defects are further subdivided on the basis of whether the rudimentary horn has an endometrial cavity. These malformations have also been grouped previously in the asymmetric lateral fusion defects category and are invariably accompanied by ipsilateral renal and/or ureter agenesis.
Class III: Uterus Didelphys In uterus didelphys, there is either complete or partial duplication of the vagina, cervix, and uterus.
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Section 2 Pediatric and Adolescent Disorders Class IV: Bicornuate Uterus: Complete or Partial The bicornuate uterus can be either complete or partial. In the complete form, the uterine division extends from the fundus to the internal cervical os. The uterine division in the partial bicornuate uterus is located at the fundus. The vagina and cervix are single-chambered. However, there have also been reports of duplication of the cervix.
Class V: Septate Uterus: Complete or Partial Either a complete or partial midline septum is present within a single uterus.
Class VI: Arcuate Uterus There is a small (<1.5 cm) fundal projection into a single endometrial cavity, and the external surface of the uterine fundus is convex or flat.
Class VII: Diethylstilbestrol-Related Abnormalities A T-shaped uterine cavity with or without dilated horns is evident.18
PATHOGENESIS AND DIAGNOSIS OF DEVELOPMENTAL ANOMALIES OF THE REPRODUCTIVE TRACT In this section, the pathogenesis of developmental anomalies and diagnostic approaches to these anomalies are discussed. Müllerian malformations are organized according to the ASRM classification; the discussion then considers abnormalities not classified by the ASRM system. Some anomalies are extremely rare; for these, even within a given class, specific diagnostic and management strategies have not been delineated in the literature.
Vaginal Agenesis Description and Pathogenesis
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Vaginal agenesis is the most common defect involving the vagina and uterus and is characterized by the absence or hypoplasia of the uterus and proximal vagina and, in some cases, the fallopian tubes. Frequently, this malformation is accompanied by urinary tract anomalies. Vaginal agenesis occurs when the sinovaginal bulbs fail to develop because the vaginal plate cannot form in the absence of the sinovaginal bulbs.2 It occurs in an estimated 1:5000 newborn females.19 Multiple variants have been reported, with some exhibiting complicated associated anomalies. Although the uterus is usually absent, 7% to 10% of cases will have a normal, albeit obstructed, uterus or a rudimentary uterus with functional endometrium.20 In the presence of active endometrium, the patient may experience cyclical pain. Vaginal agenesis can be partial or complete. Partial vaginal agenesis is less commonly seen and is characterized by a normal uterus with a small vaginal pouch located distal to the cervix. Complete vaginal agenesis, known as the Mayer-RokitanskyKüster-Hauser syndrome, is more common. In 90% to 95% of reported Mayer-Rokitansky-Küster-Hauser cases, the uterus is
also absent.20–22 The fallopian tubes are normal and the ovaries demonstrate normal endocrine function. Associated anomalies often coexist with vaginal agenesis. The incidence of associated urologic abnormalities varies from 15% to 40%; skeletal anomalies such as congenital fusion or absence of vertebra occur in approximately 12% to 50%.20,23 An association between the Mayer-Rokitansky-Küster-Hauser syndrome and the Klippel-Feil syndrome has been reported. Components of the Klippel-Feil syndrome include congenital fusion of the cervical spine, short neck, a low posterior hairline, and limited range of motion in the cervical spine.24 The MayerRokitansky-Küster-Hauser is also associated with the MURCS syndrome. MURCS syndrome is characterized by aplasia of the müllerian ducts and renal system as well as cervicothoracic somite dysplasia.25,26 Patients with vaginal agenesis are 46,XX. Most cases occur sporadically, although approximately 4% of reported cases are clustered in families.20,21 Abnormalities in the expression of homeobox (Hox) genes are associated with müllerian duct agenesis. It has been reported that increased exposure to galactose is responsible for abnormal vaginal development based on the finding that vaginal agenesis has been reported to be associated with variants of the galactose 1-phosphate uridyl transferase enzyme.27–29 Other authorities have speculated that mutations in either the antimüllerian hormone or müllerian inhibitory substance gene or its receptor gene are responsible for this disorder.4 In a recent report, a de novo translocation in a young woman with Mayer-Rokitansky-Küster-Hauser syndrome is discussed, suggesting that this break point may be involved in midmüllerian differentiation.30 Diagnosis of Vaginal Agenesis
Vaginal agenesis is usually diagnosed at puberty when young adolescents present with primary amenorrhea. Indeed, vaginal agenesis is the second most common cause of primary amenorrhea in adolescents.20,21 Normal growth and development and the presence of age-appropriate secondary sexual characteristics are all evident. The external genitalia have a normal appearance, although visual inspection can often reveal a patulous urethra.30,31 The appearance of the vagina can be diverse; it can be completely absent or can be present as a short, blindingending pouch or as a vaginal dimple. The appearance of the vaginal dimple can range from a slight indentation to up to 5 to 6 cm in length. A uterus is not palpated on rectal examination. Pelvic ultrasonography can support the clinical findings of an absent uterus or uterine remnant and the presence of normal ovaries. Magnetic resonance imaging (MRI) is extremely useful for those cases in which ultrasound findings are not definitive; lack of visualization of the vagina and a uterus in a technically adequate study indicates agenesis or hypoplasia of these structures.32–34 Laparoscopy is not usually indicated unless the diagnosis cannot be determined by other studies or if there is concern over the presence of a functioning uterus or rudimentary uterine tissue.
Unicornuate Uterus Description and Pathogenesis
A unicornuate uterus occurs when one of the paired müllerian ducts fails to elongate while the other develops normally. This
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Chapter 12 Congenital Anomalies of the Female Reproductive Tract anomaly accounts for approximately 13% of all müllerian duct abnormalities.35 These ASRM class II uterine defects are structurally quite diverse. The unicornuate uterus may occur in isolation but is frequently accompanied by a rudimentary horn.35,36 Associated urologic anomalies frequently (44%) occur, especially when the rudimentary horn is obstructed. These anomalies include ipsilateral renal agenesis (67%), horseshoe kidneys, or ipsilateral pelvic kidney (15%).35,36 Obstetric outcomes are generally poor, although normal pregnancies can occur. Because these anomalies are uncommon, most reports do not classify reproductive outcomes according to the various malformation subclasses.35 For the entire unicornuate class, the spontaneous abortion rate is 51%, the preterm birth rate is 15%, and the fetal survival rate is approximately 40%.37 Common obstetrical complications include malpresentation, intrauterine growth retardation, and preterm birth.37–41
identified. A history of second-trimester spontaneous abortions is often a clue to this condition. Uterus didelphys with obstructed unilateral vagina can be diagnosed early and accurately. The clinical presentation is similar to that in patients having a unicornuate uterus and noncommunicating, functional horn.35,38 Ipsilateral renal agenesis frequently accompanies both these conditions as well.46,47 On pelvic examination, one cervix is identified, and a paravaginal cystic-type structure can usually be palpated that represents the noncommunicating second vagina. Preoperative diagnostic studies are similar to those used for the unicornuate uterus and include HSG, pelvic ultrasound or MRI, and an IVP or renal ultrasound to either confirm or exclude associated urinary tract anomalies.33,34,42
Diagnosis of Unicornuate Uterus
Pathogenesis
Although a hysterosalpingogram (HSG) is useful in diagnosing a unicornuate uterus, it cannot detect a noncommunicating rudimentary horn. MRI can reliably identify a noncommunicating horn and is characteristically not opacified when the endometrium is absent.32 High-resolution ultrasound evaluation can usually identify rudimentary horns and is more reliable than laparoscopy in determining whether the horn is communicating. Indeed, laparoscopy is rarely indicated as part of the diagnostic evaluation of an obstructed, noncommunicating horn. Additional studies should include an intravenous pyelogram (IVP) or renal ultrasound to evaluate for ipsilateral renal agenesis, a horseshoe kidney, or an ipsilateral pelvic kidney.35,42
Müllerian ducts that incompletely fuse at the level of the uterine fundus result in the bicornuate uterus malformation. The lower uterus and cervix are completely fused, but the incompletely fused ducts elongate and develop into two separate uterine horns. Their respective endometrial cavities communicate, although an intervening muscular uterine septum is present. A single-chamber cervix and vagina are present. The subclassification of this anomaly is contingent on whether the separation is complete or partial. Complete variants include the uterus bicornis unicollis, in which the uterine cavity division extends to the internal os, and the uterus bicornis bicollis, in which the division extends to the external os. Partial bicornuate uteri are characterized by a uterine division that is confined to the fundal region. In this anomaly, the uterine cavity division corresponds to a visible sagittal groove on the external fundal uterine surface. The depth of the groove and the extent of the separation are subject to the length of the incompletely fused müllerian ducts.35,48 Usually the bicornuate uterus is an incidental finding. Women with this uterine malformation usually have no difficulty becoming pregnant, and approximately 60% can expect to deliver a viable infant.36 However, they can present with late abortion or premature labor. This observation may be related to whether the bicornuate uterus is partial or complete. According to one study, women with partial bicornuate uterus experienced a spontaneous abortion rate of 28% and preterm delivery rate of 20%. These rates contrasted with a spontaneous abortion rate of 66% and a higher rate of preterm deliveries in women diagnosed with a complete bicornuate uterus.35
Uterus Didelphys Pathogenesis
Either unilateral or bilateral duplication of the müllerian ducts can result in uterus didelphys. This anomaly is characterized by the presence of two separate, normal-sized uteri and cervices that are fused at the lower uterine segment. Vaginal duplication is frequently a component, and an associated vaginal septum is often seen. A longitudinal (horizontal) septum extends either completely or partially from the cervices to the introitus. A complete vaginal septum with a sagittal orientation occurs in approximately 75% of cases; some have occasional obstructing transverse septum.43–45 Uncommonly, patients can present with an obstructed unilateral vagina. This abnormality is frequently associated with ipsilateral renal and ureter agenesis and is a component of the Wunderlich-Herlyn-Werner syndrome.46,47 Reported reproductive outcomes are slightly better for uterus didelphys than for the unicornuate uterus. Fertility is not compromised, but the spontaneous abortion rate is high (40%). However, when the pregnancies are carried to term, few obstetrical difficulties occur.35,37,38 Diagnosis of Uterus Didelphys
A nonobstructed uterus didelphys is usually asymptomatic until menarche. Thereafter, the most frequent complaint is the inability to obstruct menstrual flow with a tampon due to the second, unimpeded vaginal outlet. Often the diagnosis is rendered at the initial pelvic examination when two cervices are
Bicornuate Uterus
Diagnosis of Bicornuate Uterus
It is extremely important to distinguish the bicornuate from the septate uterus for two reasons. First, bicornuate uteri are associated with minimal reproductive problems, whereas septate uteri have a high association with reproductive failure. Secondly, the surgical approaches involved in their treatment markedly differ. Evaluation begins with an ultrasound performed during the luteal phase of the menstrual cycle when the endometrial echo complex is better identified.42 Ultrasound based on the angle between the two cornu cannot accurately distinguish the bicornuate uterus from the septate uterus, and MRI must be
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Section 2 Pediatric and Adolescent Disorders performed to establish this diagnosis. HSG, usually the cornerstone in diagnosing most uterine structural anomalies, cannot reliably distinguish between these two entities because they can display similar uterine cavity images.49,50
Septate Uterus Pathogenesis
Diagnosis of Arcuate Uterus
The septate uterus is the most common müllerian duct abnormality. The anomaly is a result of incomplete resorption of the medial septum and occurs after the fusion of the paramesonephric ducts. The septum is located in the midline fundal region and is composed of poorly vascularized fibromuscular tissue. This contrasts with the muscular septum found in the septum of the bicornuate uterus; the differences in these components reflects developmental arrests at different points in time. There are three types of septa: complete, partial, and segmental. The complete septum extends from the fundus to the internal os, dividing the endometrial cavity. The partial septum is located at the fundus; the segmental septum, also located at the fundus, is noncontiguous, allowing for partial communication between the endometrial cavities.51,52 The fertility of women with this type of anomaly is not significantly compromised. However, the septate uterus is associated with the poorest reproductive outcomes of all the müllerian duct anomalies. Spontaneous abortion rates of 67% have been reported, and the live birth rate ranges from 15% to 28%; obstetric complications such as incompetent cervix, premature labor, and abnormal presentation are common.53–56 Hysteroscopic resection of the septum increases the live birth rate to as high as 75%.
There is limited data regarding the diagnosis, management, and reproductive outcomes for the arcuate uterus. Using HSG, a single uterine cavity with a saddle-shaped fundus can be identified. MRI shows a normal fundal contour with a minimal indentation.58,59 Renal ultrasound and IVP may be performed to exclude any associated urinary tract anomalies, although these studies generally are not part of a standard evaluation. Management is similar to the septate uterus with only selected patients fulfilling criteria for poor reproductive performance recommended for surgical correction.
Diagnosis of the Septate Uterus
HSG is an essential study in diagnosing and planning surgery for the septate uterus. It can assess the presence of a twochambered uterus, determine the length and thickness of the septum, and permit concomitant assessment of tubal patency. However, HSG is limited since it cannot distinguish the septate from the bicornuate uterus or detect minor septal defects.50 MRI provides excellent tissue characterization and can reliably differentiate between septate uterus and bicornuate uterus.56 Transvaginal ultrasound can also be useful in identifying this abnormality. In one study, transvaginal ultrasound had a sensitivity of 100% and a specificity of 80% in detecting the septate uterus.57 Additionally, if three-dimensional ultrasound is available, the reported accuracy was 92% for the diagnosis of septate uterus.
Arcuate Uterus Description
178
uterus represents a normal variant because it is not associated with an increased risk of spontaneous abortion or other pregnancy complications. Interestingly data on outcome after resection of the septum in a septate uterus demonstrates that leaving approximately 1 cm of septum will not affect pregnancy outcomes.
The arcuate uterus has a small (<1.5 cm) septate projection located at the fundal aspect of the uterine cavity. The external contour of the uterus is convex or flat. This congenital anomaly is the most common uterine abnormality detected using HSG.58,59 Classifying the arcuate uterus has been challenging. Earlier classification systems considered it a mild form of the bicornuate uterus and the ASRM classification places this anomaly in a separate class.18 Some speculate that the arcuate
Diethylstilbestrol-Related Anomalies Pathogenesis
DES is a synthetic estrogen prescribed from the late 1940s to the 1970s to prevent recurrent pregnancy loss, premature delivery, and other obstetric problems. In the early 1970s it was found to be a teratogen and its use during pregnancy was banned.60 It is now known that there is a strong association between in utero DES exposure and an increased risk of developing vaginal adenocarcinoma later in life. Additional studies revealed that in utero DES exposure was also associated with structural abnormalities of the developing uterus, cervix, and vagina. Although some women exposed to DES in utero are in their midthirties, the majority of these women are now postmenopausal or approaching the end of their reproductive years. Uterine anomalies include a T-shaped endometrial cavity, widened lower uterine segment, midfundal constrictions, endometrial filling defects, and uterine hypoplasia.61,62 DESassociated structural abnormalities of the cervix also have been identified but are less frequent than those of the uterus. These abnormalities include cervical hypoplasia, anterior ridge or collar (cock’s comb cervix), and pseudopolyps. Vaginal adenosis and vaginal constrictions have also been associated with DES.61,62 Interestingly, uterine anomalies similar to those related to DES exposure have been reported in women without in utero DES exposure. Although there is no convincing evidence that in utero DES exposure has an unfavorable impact on fertility, there is considerable evidence to indicate that many patients with DES exposure will have poor obstetrical outcomes. Complications include an increased risk of spontaneous abortions, ectopic pregnancies, and cervical incompetence.63 However, it remains uncertain whether the anomalies themselves or some subclinical abnormality of these women’s reproductive tracts are responsible for these associations. Diagnosis of DES-Related Anomalies
These anomalies of the uterine cavity and endocervix are diagnosed exclusively by HSG. MRI and ultrasound are uncommonly required.49,50 Abnormalities of the vagina and ectocervix are diagnosed by direct visualization at the time of speculum
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Chapter 12 Congenital Anomalies of the Female Reproductive Tract examination. Cervical changes often indicate coexisting uterine anomalies. In one study, 86% of women with a history of in utero DES exposure that had cervical changes also had concomitant uterine abnormalities.61 No associations between DESrelated anomalies and urinary-renal system anomalies have been identified, and this would preclude the need for imaging of the renal system. Unfortunately, DES-related abnormalities are not amenable to surgical repair. Any pregnant patient having any of these anomalies must be monitored for the potential complications described.
Transverse Vaginal Septum Pathogenesis
A transverse vaginal septum is one of the rarest congenital anomalies of the female reproductive tract, with a frequency of 1 in 70,000 females.64,65 This malformation arises either from incomplete vertical fusion between the caudal aspect of the sinus tubercle and sinovaginal bulbs or because the vaginal plate fails to canalize. The septum divides the vagina into two segments, thereby reducing its functional length. It can be located at nearly all levels in the vagina and may be perforate or imperforate. The majority of septa (46%) are located at the superior aspect, at the putative junction between the vaginal plate and caudal aspect of the uterovaginal primordium. The next most common site is the midvagina (40%), followed by the inferior vagina (14%).66 Urologic defects are only occasionally seen with a transverse vaginal septum. Instead this anomaly is often associated with other structural anomalies, including imperforate anus, bicornuate uterus, coarctation of the aorta, atrial septal defect, and malformations of the lumbar spine.65 Although there are no indications that a transverse vaginal septum is genetic, an autosomal disorder associated with a transverse vaginal septum and hydromucocolpos has been discovered in the Amish community.65 Diagnosis of Transverse Vaginal Septum Fetus, Neonate, and Infant
Before puberty, a transverse vaginal septum can sometimes manifest as hydromucocolpos. In rare cases, a hydromucocolpos can be diagnosed in utero during a third-trimester transabdominal ultrasound, which reveals fetal abdominal distension secondary to an abdominal or pelvic mass.67 Diagnosis of hydromucocolpos in the neonate and infant can be challenging. Indeed, unless significant hydromucocolpos is evident, a transverse vaginal septum is rarely diagnosed. In these cases a large mass is palpated in the lower abdomen, but unlike an imperforate hymen, the obstruction is well within the vagina so that an introital bulge will not be visible. Although rare, profuse amounts of fluid can collect in the vagina superior to the obstructing septum, resulting in a mass effect that compresses the surrounding organs. The compression may cause serious consequences if not promptly diagnosed and treated.68 Initial studies include an abdominal-pelvic ultrasound. Proper imaging studies can frequently eliminate the need for laparoscopy or laparotomy. MRI is useful in depicting pelvic anatomy and determining the thickness of the vaginal septum and should also be performed.65
Young Adolescent
In young adolescents, the transverse vaginal septum is usually undetected until menarche. After menarche, the presentation varies, depending on whether the septum is complete or incomplete. When the septum is complete, the patient commonly presents with primary amenorrhea and cyclic pelvic pain. Similar to an imperforate hymen, the symptoms are related to obstructed menstrual flow with retention of mucus and/or blood. A lower abdominal or pelvic mass is often palpated and is secondary to a hematocolpos, hematometrium, hematosalpinx, or even hemoperitoneum. The hymen is generally open and there are no bulging membranes on Valsalva. When the septum is incomplete, presenting complaints often include a foul-smelling vaginal discharge, dyspareunia secondary to a short vagina, and infertility. Because an incomplete transvaginal septum allows menstrual flow to escape periodically, a hematocolpos and hematometrium often develop over time. For patients who become pregnant, a transverse vaginal septum can cause soft tissue dystocia.64
Imperforate Hymen Pathogenesis
This anomaly is the most common obstructive condition of the female reproductive tract. The embryonic defect that gives rise to the imperforate hymen occurs when the inferior aspect of the vaginal plate fails to perforate (open). It appears to be an isolated condition, although there are some reports of familial occurrences.69 Diagnosis of Imperforate Hymen
In many cases the diagnosis is rendered at birth, because these infants will often have a mucocolpos, which results in distension of the imperforate hymen. When this occurs, a thin membrane can be visualized within the hymenal ring. If not diagnosed in early infancy, the mucus is resorbed and the distended hymen retracts. At puberty, the hymen can then again become distended from menstrual-associated hematocolpos.70 Often the patient complains of back and cyclic abdominal pain, pain on defecation, difficulty with micturition, and amenorrhea. Examination of the external genitalia reveals a bulging, blue mass at the introitus, and rectoabdominal palpitation confirms a distended vagina (Fig. 12-4). In these cases, retrograde menstrual flow into the abdominal cavity can predispose the patient to endometriosis.
Vaginal Atresia Pathogenesis
This anomaly results when the urogenital sinus fails to contribute to the inferior portion of the vagina.2,8 The müllerian structures are usually normal, but the lower portion of the vagina is completely replaced by fibrous tissue. Vaginal atresia can clinically mimic vaginal agenesis and an imperforate hymen. Most cases of vaginal atresia occur sporadically. However, vaginal atresia has also been described as a component of an autosomal recessive syndrome that includes a multitude of other anomalies, including middle ear ossicle anomalies and renal dysgenesis.71,72
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Section 2 Pediatric and Adolescent Disorders Table 12-1 Causes of Ambiguous Genitalia Genetic Female (female pseudohermaphrodite) Congenital adrenal hyperplasia Cytochrome P450 21-hydroxylase deficiency 3 β-hydroxysteroid dehydrogenase deficiency 11 β-hydroxylase deficiency Maternal ingestion of androgenic steroids Androgen-producing tumors in the fetus or mother Genetic Male (male pseudohermaphrodite) Impaired development of the testes Leydig cell aplasia Androgen insensitivity syndrome Maternal ingestion of estrogens or anti-androgens Enzyme defects 5 α-reductase type 2 deficiency Cytochrome P-450 17-hydroxylase deficiency 3 β-hydroxysteroid dehydrogenase 17-ketosteroid reductase
Figure 12-4
Hematocolpos resulting from an imperforate hymen.
Diagnosis of Vaginal Atresia
Young women with vaginal atresia usually present with primary amenorrhea. Physical examination reveals achievement of ageappropriate developmental milestones and normal secondary sexual characteristics. A midline pelvic mass can often be palpated on abdominal-rectal examination. External genitalia are generally normal with a vaginal dimple at the introitus. Abdominal ultrasound reveals the presence of ovaries, uterus, cervix, and an obstructed, blind-ending superior vagina. This is in contradistinction to vaginal agenesis, in which the uterus and cervix are absent and only the ovaries are seen.73 MRI can aid in detecting the presence of a cervix, which distinguishes this anomaly from cervical agenesis. Additionally, MRI can determine the presence of a functioning endometrial cavity.74 Obviously, these patients are not candidates for HSG studies. The karyotype is 46,XX and endocrine studies are normal.
CONGENITAL ABNORMALITIES OF THE EXTERNAL GENITALIA
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Ambiguity of the external genitalia is the result of defects during the processes of sexual determination and differentiation (Table 12-1).9 Four major groups account for most disorders resulting in ambiguous genitalia; they include female pseudohermaphroditism, male pseudohermaphroditism, gonadal differentiation disorders, and malformation syndromes. The discovery of ambiguous genitalia in an infant requires special investigative studies to determine the presence of life-threatening conditions. Multispecialty consultations are indicated. An important issue to be addressed at this time includes determining the sex of rearing. In older patients presenting with ambiguity of sexual development, quality of life issues and reproductive potential are the major concerns.
Female Pseudohermaphroditism In general, two pathophysiologic groups account for nearly all cases of female pseudohermaphrodites; these groups include congenital adrenal hyperplasia (CAH) and exogenous in utero androgen exposure. Salient characteristics of female pseudohermaphrodites include a 46,XX karyotype and virilized external genitalia in the presence of ovaries, well-developed müllerian structures, and regression of Wolffian ducts. Many of these individuals are potentially fertile.
Congenital Adrenal Hyperplasia The most frequent metabolic cause of ambiguous genitalia in the newborn is female pseudohermaphroditism due to CAH.75,76 CAH represents a group of autosomal recessive disorders that includes enzymatic defects resulting in impaired adrenal steroidogenesis (Fig. 12-5).75–77 All forms of CAH have in common these endocrine irregularities: diminished cortisol production, increased corticotropin levels, adrenal hyperplasia, and overproduction of intermediate steroids. The metabolic intermediates are typically shunted to other enzymatic pathways and result in the production of androgenic steroids. It is these steroids that cause virilization of the female fetus in utero. The extent of virilization will depend on androgen levels, but often includes varying degrees of posterior labial fusion, clitorimegaly, and vaginal introitus abnormalities. When CAH occurs in males, genital enlargement and hyperpigmentation of the skin are often seen. 21-Hydroxylase Deficiency: Classic Salt-Losing and Simple Virilizing Variants
The most common form of CAH is a deficiency of cytochrome P450 21-hydroxylase; this is responsible for 90% to 95% of these cases.78 Cytochrome P450 21-hydroxylase deficiency is categorized into classic and nonclassic types. In the classic form, the condition presents at birth. It is divided into two subtypes based on the severity of the enzymatic defect. Seventy-five
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Cholesterol CYP11A (P450scc)
Δ4 PATHWAY
Δ5 PATHWAY
LH
Pregnenolone 3βHSD
CYP17 (P450c17)
Corpus Luteum 17OH Pregnenolone
Progesterone
Theca cells 17,20 lyase
CYP17
17OH Progesterone
CYP21
CYP21
CYP17
DHEA
3βHSD
CYP17
11- Deoxycorticosterone CYP11
11 Deoxycortisol
Corticosterone
CYP11B1
17βHSD ANDROSTENEDIONE
Cortisol
TESTOSTERONE
CYP19 (P450arom)
18-OH Corticosterone
CYP19
FSH
17βHSD ESTRONE
ESTRADIOL
Aldosterone Granulosa cells Adrenal gland Figure 12-5 Steroid hormone biosynthesis pathways. The Δ4 pathway converts pregnenolone to progesterone and is the main pathway in the corpus luteum. The Δ5 pathway converts pregnenolone to androgens and subsequently estrogens and is the preferred pathway in the thecal cells. Also shown are the conversion of 17OH-progesterone to aldosterone and cortisol as a result of CYP21 and CYP11, which occurs exclusively in adrenal gland. A single arrow denotes irreversible reactions, and double arrows denote reversible reactions.
percent of these infants will have the severe salt-losing form, in which aldosterone production is significantly impaired.78 The remainder of infants with classic 21-hydroxylase deficiency have the simple virilizing form, in which aldosterone production is adequate and there is no salt wasting. The incidence of classic CAH varies among different ethnic groups and occurs in 1:15,000 live births worldwide.78,79 Nonclassic 21-hydroxylase deficiency is characterized by a partial enzymatic defect; this type is associated with neither ambiguous genitalia nor salt wasting. It is usually detected later in life and is often confused with polycystic ovary syndrome.80 Pathogenesis
The enzyme 21-hydroxylase is a cytochrome P450 protein, designated CYP21, and functions in both cortisol and aldosterone synthesis. The CYP21 gene is localized to chromosome 6p21.3
and encodes this enzyme. Either a mutation or partial deletion in this gene can result in markedly reduced or absent enzyme activity.78,79 In classic 21-hydroxylase deficiency, both alleles of the CYP21 gene are affected and three major endocrine regulatory systems are disrupted: the hypothalamic-pituitaryadrenal axis, renin-angiotensin-aldosterone axis, and hypothalamicpituitary-gonadal axis. As a consequence, cortisol, aldosterone, and gonadal sex steroid production is altered. Excess androgen production in utero results in abnormal clitoral growth and virilization of the urogenital structures. Newborn females with either the salt-losing or simple virilizing forms of cytochrome P450 21-hydroxylase deficiency have ambiguous genitalia with appearances that can range from mild clitorimegaly to fully masculinized penile urethra. Affected male infants generally have no genital malformations at birth, but continued androgen excess results in accelerated body growth.
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Section 2 Pediatric and Adolescent Disorders In classic salt-losing 21-hydroxylase deficiency, infants are unable to retain sodium and excrete potassium from the renal tubules. The infant will often present with hyponatremia, hyperkalemia, hypotension, and metabolic acidosis. Importantly, this condition can lead to cardiovascular collapse.78,79
associated with mild virilization in female infants and undervirilization of newborn males. Newborns of both sexes may have salt-wasting because of deficiencies in aldosterone and other mineralocorticoids.85 Pathogenesis
Diagnosis
The accurate diagnosis of 21-hydroxylase deficiency is based on observations from the physical examination and laboratory studies. Laboratory tests reveal the following abnormalities: decreased serum cortisol and aldosterone levels (in salt-losing form), increased serum 17-hydroxyprogesterone and increased urinary pregnanetriol, a metabolite of 17-hydroxyprogesterone. Salt-losing 21-hydroxylase deficiency is also accompanied by decreased serum sodium, increased potassium, and increased plasma renin activity. The diagnosis of cytochrome P450 21-hydroxylase deficiency can also be rendered using allele-specific polymerase chain reaction in affected infants.81 11β-Hydroxylase Deficiency
Defects in 11β-hydroxylase are the second most common cause of all CAH-associated ambiguous genitalia, representing 5% to 8% of these cases. The clinical presentation can be quite varied, with symptoms occasionally overlapping with those seen in 21hydroxylase deficiency. Excessive virilization of genitalia is often seen in 46,XX females and gender-appropriate masculinization in 46,XY males.82 Pathogenesis
The CYP11B1 gene, located on chromosome 8q21, encodes for the enzyme 11β-hydroxylase.82,83 Mutations in the gene result in impaired conversion of 11-deoxycortisol to cortisol and 11-deoxycorticosterone to corticosterone. The intermediate corticoids are shunted to form androgenic steroids. Accumulation of mineralocorticoids results in hypernatremia, hypokalemia, plasma volume expansion, and hypertension. Diagnosis
The diagnosis of 11β-hydroxylase deficiency can be established by the clinical observation of ambiguous genitalia in the female along with laboratory abnormalities. The following abnormalities are commonly identified: increased serum sodium, decreased serum potassium, decreased serum cortisol, increased serum 11deoxycortisol, increased serum desoxycorticosterone, increased 24-hour urinary 17-ketosteroids, decreased plasma renin activity, and increased ratio of tetrahydrocompounds (11-deoxycortisol to cortisol).84 3β-Hydroxysteroid Dehydrogenase Deficiency
182
Deficiency of 3β-hydroxysteroid dehydrogenase (3βHSD) accounts for less than 5% of all CAH cases.85 It is the only form of CAH associated with genital ambiguity in both males and females. In most cases the adrenal insufficiency is quite severe. There is reduced synthesis of all three groups of adrenal corticosteroids, with elevated serum levels of pregnenolone, 17hydroxypregnenolone, and dehydroepiandrosterone (DHEA). A variety of phenotypic manifestations can present in infants as well as older individuals. Production of the more potent androgens is blocked, and DHEA is the major intermediate that accumulates. DHEA is a weak androgen, and it is
The HSD3B2 gene is located on chromosome 1 and encodes for two isoforms of the 3βHSD enzyme, Type I and Type II. Type I, located in the liver and peripheral tissue, is not associated with mutations affecting enzymatic activity of the enzyme. Type II is located in the adrenal glands and gonads and is associated with a number of mutations affecting enzymatic activity. Patients with the salt-losing disorder have no functional 3βHSD Type II activity; those with the nonsalt-wasting variant will demonstrate partial enzyme activity.86,87 Diagnosis
In infants with the salt-wasting form, early diagnosis and replacement of glucocorticoids and/or mineralocorticoids are essential to avoiding adrenal crisis and death. Affected female neonates can appear normal or have clitorimegaly and labial fusion. Most newborn males will have incompletely masculinized genitalia with varying degrees of hypospadias.85,86 The testes often descend and can be palpated in the inguinal canal or labioscrotal folds. Signs of adrenal insufficiency may also be present. Salt-losing manifestations occur between day 6 to 14 of life and are evidenced by the following laboratory studies: decreased serum sodium, increased serum potassium, and decreased serum aldosterone. The increase in plasma renin activity is the most sensitive indicator of aldosterone deficiency. Elevated ratios of 17-hydroxypregnenolone to 17-hydroxyprogesterone and DHEA to androstenedione are often present. In aldosterone deficiency, dietary salt tablets can be provided along with the mineralocorticoid fludrocortisone acetate. Close monitoring of daily weights, electrolytes, fluid status, and plasma renin activity is indicated.88 In some cases, plasma renin activity increases in the absence of aldosterone deficiency and salt losing. For these patients, fludrocortisone acetate improves renin activity and hormonal control. Therapy is initiated as soon as possible. In infants, hydrocortisone therapy may reverse the virilizing effects of the excess androgens.
Exogenous Androgens due to Medications or Maternal Production Maternal ingestion of androgens or other medications, such as danazol and progestins, before week 14 of gestation can result in clitorimegaly and labial fusion. Clitorimegaly without labial fusion is seen when exogenous androgens are given at or after 14 weeks’ gestation. If maternal ingestion has been excluded, a physical examination and laboratory studies directed at locating the source of virilization are indicated.
Male Pseudohermaphroditism Male pseudohermaphrodites are genetic 46,XY males; they have testes but exhibit incompletely masculinized external genitalia. Discovery of this condition generates a number of diagnostic and therapeutic challenges for the clinician. Unlike female
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Chapter 12 Congenital Anomalies of the Female Reproductive Tract pseudohermaphroditism, in which most cases are caused by CAH and exogenous androgens, a constellation of disorders can result in male pseudohermaphroditism and in many cases a definitive diagnosis cannot be rendered.87 The various etiologies of male pseudohermaphroditism can be generically grouped into two categories based on whether there is a defect in androgen action or androgen synthesis. The two most common disorders of androgen action include 5-αreductase deficiency, which is inherited as an autosomal recessive trait, and androgen insensitivity, an X-linked recessive disorder. Defects in androgen synthesis all exhibit autosomal recessive inheritance. Another etiology, persistent müllerian duct syndrome, is caused by defects in antimüllerian hormone synthesis and it also exhibits autosomal recessive inheritance. Defects in Androgen Action: 5-α-Reductase Type 2 Deficiency
In 5-α-reductase type 2 deficiency (5-ARD), the external genitalia can manifest a wide spectrum of appearances, ranging from normal female anatomy to male anatomy exhibiting hypospadias and/or micropenis. The characteristic findings often include a clitoris-like phallus, hypospadias, bifid scrotum, and a persistent urogenital sinus that opens at the perineum. A vaginal introitus leading to a blind-ending pouch can often be encountered. Testes are often palpated in the labioscrotal folds or inguinal canals, although intra-abdominal testes also occur. Many individuals with 5-ARD virilize during early adolescence, and this disorder has been historically referred to as “penis at 12.” In the past, these individuals were often reared as females. At puberty, when the genitalia underwent masculinization due to an increase in type 1 enzyme activity, they then changed gender.89 Obviously, the major issue with 5-α-reductase type 2 deficiency is determining the sex of rearing. Pathogenesis
The defect in androgen action is related to mutations in the 5-α-reductase type 2 enzyme, which converts testosterone to the more physiologically active form, dihydroxytestosterone (DHT) in androgen-dependent tissues. The enzyme is encoded by the SRD5A2 (or 5α-RD2) gene on chromosome 5. More than 40 mutations have been reported in all five exons of this gene. Although most mutations are amino acid substitutions, other mutations, including complete deletions, nonsense, and/or splice site mutations, have been reported.90 Masculinization of external genitalia and differentiation of the urogenital sinus depends on DHT. Incomplete masculinization occurs as the result of decreased conversion of testosterone to the active DHT. Because testosterone levels are normal, dependent Wolffian duct structures are not affected. Antimüllerian hormone is normally produced and therefore all müllerian duct development is arrested. Diagnosis
The diagnosis of 5-ARD is often rendered at birth. However, near-identical phenotypes can occur in androgen insensitivity syndrome. Preliminary laboratory testing reveals normal or slightly increased serum testosterone levels with decreased DHT. On stimulation by human chorionic gonadotropin (hCG), the characteristic lab finding is an increased testosterone to DHT ratio (>20). Cultured genital skin fibroblasts are used to measure 5-α-reductase type 2 enzyme activity by assaying the
conversion of testosterone to DHT.89 In androgen insensitivity syndromes the ratio of testosterone to DHT is not increased. Androgen Insensitivity Syndrome
There are two forms of androgen insensitivity syndrome, complete and partial; each depends on the amount of residual androgen receptor function. Complete androgen insensitivity syndrome is characterized by the failure of Wolffian duct-derived structures to develop. There are no ambiguous genitalia, although features of testicular feminization, such as a normal labia, clitoris, and a vaginal introitus, are evident. Testes can occasionally be palpated in the inguinal region; when this occurs in a phenotypic female, it is imperative to determine the contents,90 because 7% of newborn females with an inguinal hernia and no cervix by palpation or vaginoscopy are either male pseudohermaphrodites, usually secondary to androgen insensitivity syndrome, or have mixed gonadal dysgenesis.91 In partial androgen insensitivity syndrome, ambiguous genitalia with varying degrees of Wolffian development and labioscrotal fusion are found. Pathogenesis
The androgen action defect is due to a mutation in the androgen receptor gene with impaired binding of testosterone and DHT in androgen-dependent target organs. The androgen receptor gene has a loss-of-function mutation localized to Xq11-13. The typical postreceptor events that mediate androgen effects on target tissues do not occur, despite normal levels of androgen synthesis, and prenatal undervirilization of external genitalia occurs.92 More than 250 mutations have been described, including complete and partial gene deletions, point mutations, and small insertions/deletions.93 As expected, an assortment of functional defects can arise from any of these mutations. Some defects result in complete loss of cell surface receptors, whereas others exhibit incomplete protein synthesis due to modifications in substrate binding affinity. Binding affinity alterations can contribute to a loss of signal transmission, despite the presence of normal cell surface receptors. In complete androgen insensitivity syndrome, the genotypes are consistent with most phenotypic presentations. However, the same is not true for partial androgen insensitivity syndrome.93 Normal antimüllerian hormone levels result in müllerian duct regression. However, Wolffian duct structures fail to develop properly due to diminished to absent testosterone and DHT binding. Diagnosis
Screening hormone levels are within normal limits. However, the hCG stimulation study reveals an increase in both testosterone and DHT. Diagnostic confirmation can be rendered either by mutational analysis of the androgen receptor gene, which detects greater than 95% of the complete and partial androgen insensitivity syndrome mutations or by measuring androgen receptor binding in scrotal skin, which should be reduced.91 Sonography can be useful in identifying the presence of any müllerian structures. When present, the diagnoses of complete and partial androgen insensitivity syndrome are excluded. Leydig Cell Hypoplasia or Agenesis
Leydig cell hypoplasia is an autosomal recessive disorder in which Leydig cell differentiation and testosterone production are impaired. The estimated incidence of Leydig cell hypoplasia
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Section 2 Pediatric and Adolescent Disorders is 1:1,000,000 and preliminary laboratory findings usually reveal markedly reduced serum testosterone and elevated LH levels.94 The phenotype depends on the extent of intrauterine testosterone secretion, and affected males can present with a wide variety of external genital abnormalities.
3β-Hydroxysteroid Dehydrogenase Deficiency
Pathogenesis
17-α-Hydroxylase Deficiency
In most cases of Leydig cell hypoplasia, the androgen action defect is due to point mutations in exon 11 of the LH receptor gene.94,95 Testosterone synthesis by the fetal testes is diminished, and masculinization of the external genitalia is altered. Sertoli cells are present, producing antimüllerian hormone, and müllerian duct structures regress. Type I Leydig cell hypoplasia is the most severe form of this disorder and involves inactivating mutations in the LH receptor gene that prevent signal transduction.96 This break in the signal pathway results in significant decreases in testosterone production by the fetal testes. The androgen deficiency is milder in type II Leydig cell hypoplasia, in which mutations in the LH receptor gene only partially inactivate signal transduction.94,95
Deficiency of 17-α-hydroxylase is characterized by reduced to absent gonadal and adrenal sex hormones with increased synthesis of mineralocorticoid precursors. In newborn males, ambiguous genitalia are evident, whereas sexual infantilism is present in newborn females. Varying degrees of hypertension and hypokalemia accompany this disorder. In the female, 17-αhydroxylase deficiency is often diagnosed in the young adolescent during an evaluation for delayed puberty, absent secondary sexual characteristics, or primary amenorrhea, although some cases are diagnosed at birth.99
Diagnosis
Hormone levels reveal decreased serum testosterone, decreased DHT, and increased serum LH. In the hCG stimulation study, serum levels of testosterone and DHT do not increase. On rectal examination, a uterus cannot be palpated. Abdominal ultrasound usually reveals intra-abdominal gonads. Confirmation of the diagnosis is rendered by testicular biopsy, which reveals absence or marked hypoplasia of Leydig cells, presence of Sertoli cells, and arrest of spermatogenesis in the seminiferous tubules.93 Defects in Androgen Synthesis
A defect in any of the enzymatic steps of testosterone biosynthesis from cholesterol can result in altered androgen synthesis; in the developing male, ambiguous genitalia can result. Like most inherited enzymatic disorders, these disorders are all autosomal recessive. Congenital Lipoid Adrenal Hyperplasia
Congenital lipoid adrenal hyperplasia is a rare, severe form of CAH that is fatal in two thirds of affected neonates. There is complete deficiency of all adrenal steroid hormones, and neonates present with female external genitalia and marked saltwasting. Symptoms of severe adrenal insufficiency, including failure to thrive, vomiting, diarrhea, hyponatremia, and hypokalemia, present at birth.97
3β-hydroxysteroid dehydrogenase deficiency is the only form of CAH that can manifest as either female or male pseudohermaphroditism. See the discussion of this disorder in the section on female pseudohermaphroditism in this chapter.
Pathogenesis
Mutations in the CYP17 gene can manifest as 17-α-hydroxylase deficiency, 17,20-lyase deficiency, or a combination of the two.99,100 In 17-α-hydroxylase deficiency, decreased cortisol levels stimulate corticotropin and although steroid production is increased, it is blocked proximal to the 17-α-hydroxylase step. There is compensatory accumulation of 17-deoxysteroids, including pregnenolone, progesterone, deoxycorticosterone, and corticosterone. Diminished androgen production results in hypogonadism. The mineralocorticoid activity of deoxycorticosterone causes hypernatremia and sodium retention, plasma volume expansion, and hypertension. Hypokalemia and subsequent decreased serum aldosterone and plasma renin activity are usually evident.99 Diagnosis
Markedly increased serum levels of 11-deoxycorticosterone and corticosterone confirm the diagnosis. Pregnenolone and progesterone levels are slightly increased. Serum levels of the following steroids are very low or absent: 17-α-hydroxypregnenolone, 17-α hydroxyprogesterone, 11-deoxycortisol, DHEA, androstenedione, and testosterone. Serum and urinary estrogens are decreased and corticotropin, FSH, and LH levels are all increased. The urinary metabolites 17-α-hydroxycorticosteroid and 17-ketosteroid are reduced or absent. Prenatal diagnosis of affected infants is possible by measuring adrenal steroid levels in amniotic fluid.99 17,20-Desmolase (Lyase) Deficiency
Pathogenesis and Diagnosis
184
Congenital lipoid adrenal hyperplasia is associated with mutations in two different genes. Mutations in the gene encoding steroidogenic acute regulatory protein (StAR) are responsible for most cases of this disorder. The StAR protein mediates rapid entry of cholesterol into the mitochondria and is an acute regulator of steroidogenesis.98 Mutations involving the CPY11A gene that encodes for the cholesterol side chain cleavage enzyme 20,22desmolase are less common causes of this disorder.98 Preliminary laboratory testing on infants reveals decreased glucocorticoids, mineralocorticoids, testosterone, and DHT along with decreased sodium and potassium. Most newborns do not survive infancy, and the ones that do require hormone replacement.97
In 17,20-desmolase (lyase) deficiency, the biosynthetic pathways that convert 21-carbon steroids, 17-hydroxypregnenolone, and 17-hydroxyprogesterone to 19-carbon steroids, DHEAS, and androstenedione, respectively, are disrupted.100 Diminished to absent levels of androgens, testosterone, and estradiol also occur. There can be either partial or complete blockages of these pathways, and presenting symptoms will differ depending on the enzyme block. Pathogenesis and diagnosis
As stated previously, the CYP17 gene encodes the 17-αhydroxylase 17,20-lyase complex, and defects in the gene can result in 17,20-desmolase (lyase) deficiency.99,100 Laboratory
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Chapter 12 Congenital Anomalies of the Female Reproductive Tract tests diagnostic of 17,20-desmolase deficiency include increased serum 17-hydroxypregnenolone, increased 17hydroxyprogesterone, normal FSH, increased LH, decreased testosterone (estradiol), decreased DHEA, decreased androstenedione, and normal to slightly increased pregnenolone and progesterone. 17β-Hydroxysteroid Dehydrogenase Deficiency
The diagnosis of this disorder is often rendered at puberty in genetic males. These males have either been raised as females and present with primary amenorrhea and hirsutism or have been raised as males and present with gynecomastia and incomplete male genital development.101 In affected males, the virilization, including phallic enlargement and male secondary sexual characteristics at puberty, is very similar to that seen in 5-AHD. Affected individuals are infertile. Pathogenesis
The enzyme 17β-hydroxysteroid dehydrogenase, or 17ketosteriod reductase, catalyzes the conversion of androstenedione to testosterone in the testes. Mutations in the 17-βHSD type 3 isozyme gene (HSD17B3), located on chromosome 9q22, result in deficient testosterone production. Most of these mutations are missense/nonsense.101 No significant correlation between the genotype and phenotype has been determined. Diagnosis
Ambiguous external genitalia are usually evident at birth. The most common findings include clitorimegaly, fusion of the labioscrotal folds, and blind-ending vaginal pouch. Testes can often be palpated in the inguinal canal or the labioscrotal folds, although intra-abdominal testes can occur. Similar to other forms of male pseudohermaphroditism, the internal urogenital tract is well developed. The epididymis, vas deferens, seminal vesicles, and ejaculatory ducts are all present; the prostate and müllerian structures are absent. Characteristic laboratory findings include increased ratio of androstenedione to testosterone, with serum levels revealing increased androstenedione and decreased testosterone. Prenatal diagnosis is available in the kindred of affected patients if causal mutations have been characterized.101
Persistent Müllerian Duct Syndrome Persistent müllerian duct syndrome is characterized by the presence of completely developed müllerian duct derivatives in an otherwise normally masculinized 46,XY male. Fewer than 200 cases have been reported.102 Failure of müllerian duct regression results in the presence of internal female reproductive organs in affected males, who also have varying degrees of Wolffian duct structures. Ambiguous genitalia are not often associated with this disorder, although unilateral or bilateral cryptorchidism may be present.102
Gonadal Differentiation Disorders Gonadal Dysgenesis
Gonadal dysgenesis is a descriptive term that refers to a broad category of individuals born with female genitalia, müllerian duct structures, and dysgenetic or streak gonads. The term is often used in association with Turner’s syndrome, although additional forms of gonadal dysgenesis have been described. Patients with Turner’s syndrome will not only have dysgenic ovaries, but other associated findings as well, including short stature, shield chest, and coarctation of the aorta. Chromosomal analysis reveals either an abnormality or absence of an X chromosome. Turner’s syndrome accounts for approximately 50% of patients with gonadal dysgenesis.103,104 Two additional classes of gonadal dysgenesis include pure and mixed forms. The gonads fail to develop in mixed dygenesis. Because these individuals lack proper hormonal stimulation, they often have abnormalities associated with the development of secondary sexual characteristics. They do not have any phenotypic findings associated with Turner’s syndrome. Karyotypes are either 46,XX or 46,XY.
Pure Gonadal Dysgenesis In pure gonadal dysgenesis, the gonads are dysgenetic, although the internal reproductive organs and external genitalia are normal. Occasionally, hypoplastic genitalia occur. Most cases are 46,XY, although some are 46,XX. The condition can occur sporadically or be inherited as either an autosomal recessive or X-linked trait in some cases of XY gonadal dysgenesis. In Swyer syndrome, 46,XY females present as phenotypic females, achieve average height, and exhibit none of the physical stigmata associated with Turner’s syndrome. FSH levels become elevated in early adolescence because “streak” gonads do not produce steroid hormones or inhibin. Microscopically, the dysgenetic gonads are often composed of ovarian stroma and fibrous tissue with no evidence of primordial follicles. The diagnosis is usually rendered during adolescence when these patients are evaluated for primary amenorrhea. However, in a recent report an adolescent with Swyer syndrome presenting with secondary amenorrhea is discussed.105 Patients with pure XY gonadal dysgenesis require gonadectomy because of the high risk for developing gonadoblastomas, which may transform into dysgerminomas or other germ cell neoplasms.106
Mixed Gonadal Dysgenesis Most patients with mixed gonadal dysgenesis have a mosaic karyotype, 45,X/46,XY. The condition is characterized by asymmetric gonadal development and persistence of müllerian duct structures.107 Either an abnormal testis or a germ cell neoplasm is identified along with a contralateral dysgenetic or absent gonad. Incomplete müllerian duct development is the result of a functional deficit imposed by the abnormal testis. As indicated previously, gonadectomy is indicated.
Pathogenesis and Diagnosis
This disorder is due to mutations either in the antimüllerian hormone or antimüllerian hormone receptor II genes. Ultrasound and MRI can be used to diagnose the presence of müllerian structures.
Diagnosis of Gonadal Dysgenesis
Ovarian dysgenesis is often first suspected in a young adolescent who fails to achieve normal secondary sexual milestones, such as adequate breast development and menstruation. Ultrasonography
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Section 2 Pediatric and Adolescent Disorders can confirm the presence of the dysgenetic ovaries and often reveals small atrophic structures. Although rare, steroidproducing gonadoblastomas can develop in the dysgenetic gonads and may resemble normal ovaries on ultrasound.106 Other useful imaging studies include MRI and computed tomography scan. Both 46,XX and 46,XY patients benefit from exogenous estrogens and are potential candidates for assisted reproductive technology, particularly donor oocytes.
True Hermaphroditism True hermaphroditism is the rarest of all the intersex disorders. Individuals have both ovarian and testicular tissue, although the gonad combinations vary. Gonad combinations can include one ovary and one testis, two ovotestes, one ovotestis and one ovary, or one ovotestis and one testis. More than 50% of these individuals are 46,XX; one third can be either chimeric 46,XX/46,XY or mosaic 46,XY/47,XXY or 45,X/46,XY. Very few true hermaphrodites are 46,XY.107 The amount of functional testicular tissue determines how the internal reproductive tract will differentiate. Characteristically, Wolffian ducts differentiate into male structures on the side in which the gonad is a testis, whereas müllerian ducts differentiate into female structures on the side in which testicular tissue is absent. A majority of true hermaphrodites will have a uterus, although it may be hypoplastic, and ambiguous genitalia. During puberty, most true hermaphrodites develop breasts and some even menstruate. Gender assignment should follow extended counseling that takes into consideration the internal reproductive tract, external genitalia and, depending on the age at diagnosis, the patient’s desire to be assigned one gender over another.
Congenital Abnormalities of the Ovaries Congenital anomalies of the ovaries include agenesis, supernumerary ovaries, and gonadal dysgenesis. These anomalies are all quite rare. Ovarian agenesis or dysgenesis is most often associated with a 46,XY karyotype and sexual infantilism, although cases involving 46,XX karyotype have been reported.108 Indeed, Gorgojo and colleagues recently reported a 46,XX female with gonadal agenesis and Mayer-Rokitansky-KüsterHauser syndrome.109 Supernumerary ovaries occur when ovarian tissue has been separated during development from the normally located ovary.110 Such ovaries have been found in the omentum or retroperitoneum, and their location corresponds to the migration path of the primordial germ cells. Only 15 cases have been reported, and in 5 of those (33%) cases, primary neoplasms were identified arising in the supernumerary tissue.110,111 This condition is distinguished from accessory ovaries. In accessory ovaries, the additional ovarian tissue is connected to the normally positioned ovary. It has been estimated that accessory ovaries occur in about 1 in 93,000 patients.110
Malformation Syndromes Associated with Genital Ambiguity Genital ambiguity is not always an isolated finding. Often, it can
186 be associated with a variety of malformation syndromes. A
detailed description of all of these disorders is beyond the scope of this chapter. However, some of the more common syndromes having ambiguous genitalia as one component and for which the molecular mechanisms are beginning to be elucidated are discussed here. In addition, two well-known malformation associations related to congenital abnormalities of the reproductive tract are described. Denys-Drash syndrome is associated with XY gonadal dysgenesis and mutations of the WT1 gene. In addition to dysgenetic testis and hypoplastic müllerian duct derivatives, these patients have focal or diffuse mesangial sclerosis of the kidneys. Approximately 75% will develop Wilms’ tumor in the first decade of life.112 Camphomelic dysplasia is a lethal bony dysplasia associated with a male to female sex reversal in two-thirds of affected males. Approximately 70% of these patients present with ambiguous genitalia. Camphomelic dysplasia is inherited as an autosomal dominant trait, and the condition is associated with a heterozygous loss of function of the SOX9 coding region.113 Smith-Lemli-Opitz syndrome type I is characterized by microcephaly, mental retardation, ptosis, micrognathia, polydactyly, and micropenis. Approximately 75% of XY patients will have abnormalities of the external genitalia that vary from hypospadias to complete failure of masculinization. This syndrome is caused by a deficiency of 7-dehydrocholesterol reductase, an enzyme required in the biosynthesis of cholesterol from acetate. It is inherited as an autosomal recessive disorder.113 Antley-Bixler syndrome is a rare disorder characterized by craniosynostosis, multiple joint contractures, including radiohumeral synostosis, and ambiguous genitalia. It is associated with abnormal steroid metabolism resulting from a deficiency of lanosteral 14-α-demethylase required for cholesterol synthesis and is inherited as an autosomal dominant trait.114 Another malformation syndrome associated with ambiguous genitalia is the Meckel-Gruber syndrome. This syndrome is inherited in an autosomal recessive manner and is characterized by polycystic kidneys, occipital encephalocele, polydactyly, cleft palate, and eye abnormalities. The gene responsible for this condition has not been identified.115 Finally, two associations that have ambiguous genitalia as one component include the CHARGE and VATER associations. The CHARGE association is characterized by coloboma, heart disease, atresia choanae, retarded growth, genital hypoplasia, and ear defects. The cause of this heterogeneous condition is unknown, although a familial inheritance pattern is occasionally reported. The VATER association is characterized by vertebral, anal, tracheoesophageal, and renal anomalies. Inheritance type is unknown. These patients present with ambiguous genitalia as part of other cloacal abnormalities.116
Diagnostic Evaluation of Ambiguous Genitalia in the Infant Evaluation of an infant with ambiguous genitalia requires a thorough maternal history, physical examination, a karyotype, laboratory testing and, in some cases, radiographic studies. The results of these preliminary studies should determine whether the infant is a female or male pseudohermaphrodite, has a gonadal
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Chapter 12 Congenital Anomalies of the Female Reproductive Tract differentiation disorder, or has a malformation syndrome. Subsequent studies should be individualized to the patient and will depend on the initial findings. A detailed maternal history should be obtained as part of the initial evaluation. This history should include a comprehensive review of medications used by the mother during her pregnancy with a particular emphasis on androgens and progestational agents taken during the first trimester. Maternal exposure to environmental toxins is an important aspect of this history. A history of consanguinity renders autosomal recessively inherited disorders, such as CAH and 5-ARD, more likely. Other important aspects include unexplained early neonatal deaths that may suggest previously undiagnosed adrenal insufficiency. A complete physical examination and a thorough genital examination are essential and may indicate the etiology of the genital ambiguity. As an example, hypertension, hyperpigmentation, and signs of dehydration are suggestive of CAH. Correspondingly, observations from the physical examination may be suggestive of a malformation syndrome with ambiguous genitalia as one component. The external genitalia should be examined for the presence of gonads, noting their size, number, and location. Gonads palpated inferior to the inguinal canal region are testes until proven otherwise, and their presence renders the diagnosis of female pseudohermaphroditism unlikely. Importantly, testes do not always descend properly into the labioscrotal folds, so the absence of a palpable mass inferior to the inguinal canal does not exclude the presence of male gonads. Phallus length, diameter, and development level, along with the location of the urethral meatus, are important elements of the genital examination. The labioscrotal folds should be examined for the degree of fusion, which is suggestive of androgen exposure in utero. A rectal examination can help determine the presence of a uterus, which excludes male pseudohermaphroditism. Laboratory studies are an integral component of the initial evaluation. Because the most common etiology of ambiguous genitalia is CAH, a condition often associated with salt-wasting, electrolytes should be routinely obtained. Other important studies include a blood karyotype and the following hormone levels: 17-hydroxyprogesterone, DHEAS, testosterone, dihydrotestosterone, LH, and FSH. An ultrasound study is useful in defining the internal structures, such as uterus, ovaries, and/or intra-abdominal gonads. Either a retrograde genitogram or a voiding cystourethrogram should be performed to determine additional abnormalities of the urogenital system. Results from the history, physical examination, and laboratory studies should enable the clinician to distinguish the etiology of the ambiguity and outline a treatment course.
COUNSELING The diagnosis of any congenital anomaly involving the reproductive system will have profound implications on the patient’s sexual development and future fertility. In many cases, particularly those involving gender ambiguity, the abnormalities are often detected and diagnosed in infancy. When any deviation from normal involves the external genitalia in the neonate, gender assignments should be delayed until necessary studies have been completed. In the interim, the parents are to be
reassured that they have a “healthy baby,” but that the external genitalia have not completed development. They should be informed that additional testing should clarify the sex of rearing. Most clinicians recommend referring to the infant as the “baby” until gender assignment can be rendered. Determining the sex of rearing must be made with the parents, taking into account cultural and religious beliefs, as well as fertility issues. Once diagnosed, effective communication with family members is critical. In addition to providing details to the family on the infant’s condition, the physician should also supply information regarding support groups.117 Counseling should include a number of specialists, including geneticists, pediatricians, surgeons, and psychologists as well as obstetricians and gynecologists. A multifaceted approach is essential because the family members will be required to make decisions that will affect the patient’s sex of rearing and possibly future fertility. In some cases, families will benefit from speaking to others who have undergone similar experiences. Most centers can supply information regarding support groups, and the National Organization of Rare Disorders is a valuable resource. Gender assignment should be rendered as soon as test results are completed. Once assignment is made, steps should be made to reinforce the gender identity. Aside from patients with 5ARD, reversing gender identity after the first 2 years of life will have serious consequences. The physician should make every effort—including surgery, hormonal manipulation, and psychological support—to ensure that the infant’s genital structures conform to the patient’s own sexual identity.117 This task is sometimes difficult in infancy because one can only speculate on the newborn’s gender identity. Indeed, there has been a movement in recent years to address the problems of surgery timing in these cases. This problem is of particular concern in patients with CAH. A number of interest groups believe that genitoplasty should not be conducted without the informed consent of the involved patient. Requirements for such consent would require rethinking when such surgeries should be performed and would obviate surgery being performed in infancy. If this approach is adopted, problems still exist as to the sex of rearing, because the first 2 years of life appear to be critical in reinforcing gender identity. Müllerian duct anomalies are often diagnosed later in life and may be discovered during an evaluation for infertility. In these cases, counseling should focus not only on the prospect for the patient becoming pregnant, but also on the possibility of associated urogenital system anomalies. Counseling will also focus on the diagnosis and prevention of urogenital anomalies in future generations. This is particularly true for patients who are known carriers of the gene for CAH or have a child with this disorder. When one child is affected with CAH or if the parents are known carriers of these genes, genetic counseling can explain how the disease is inherited and what their options are during subsequent pregnancies. Prenatal prediction of CAH attributable to classic 21-hydroxylase deficiency is possible by using a number of modalities: determination of amniotic fluid hormone levels, human leukocyte antigen typing of chorionic villus cells and/or amniotic fluid cells, and molecular genetic studies of chorionic villus cells and amniotic fluid cells. Advances in genetic diagnostic techniques have rendered molecular genetic studies the diagnostic test of choice.
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gender of rearing and future reproductive potential, rendering appropriate communication and counseling imperative.
PEARLS ●
●
●
●
●
CONCLUSIONS ●
Congenital anomalies involving the internal female reproductive tract represent a morphologically diverse group of disorders. Establishing an accurate diagnosis is essential. With respect to congenital anomalies of the reproductive tract, diagnostic accuracy is essential for further management and planning treatment strategies, particularly because the surgical approach for their correction is contingent on the type of malformation and may vary within a specific group. For infants born with ambiguous genitalia, treatment will have a direct impact on the
●
●
Congenital anomalies of the female reproductive tract are almost exclusively the result of random developmental errors and rarely have identifiable underlying genetic bases. Renal and urologic abnormalities are common in women with reproductive tract anomalies, because these systems develop together. Diagnostic testing for congenital anomalies of the female reproductive tract focuses on characterizing the anomalies so that therapy, usually surgical, can optimize reproductive function. Ambiguous genitalia as a group are morphologically similar but can usually be attributed to one of a number of dissimilar etiologies. The most common cause of ambiguous genitalia is congenital adrenal hyperplasia. Infants with ambiguous genitalia should be immediately screened for electrolyte imbalances, because they can be lifethreatening. For infants born with ambiguous genitalia, gender assignment is made with the parents after thorough evaluation and is based on hormonal, anatomic, and chromosomal findings as well as cultural and religious beliefs. Adults born with ambiguous genitalia are at risk for difficulties with sexual and reproductive function as well as gender identity.
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Section 2 Pediatric and Adolescent Disorders Chapter
13
Pediatric Gynecology Ellen S. Rome
INTRODUCTION In the pediatric and early adolescent population, the gynecologic history and physical examination are a part of both routine health maintenance and the diagnosis and treatment of gynecologic problems, such as: • • • • • •
Vaginal or genital discharge, odor, rash, or itching Early or delayed sexual maturation Heavy, irregular, frequent, or painful menses Abdominal or pelvic pain or masses Genital injuries Congenital anomalies of the reproductive tract
Pediatricians, family practice physicians, and gynecologists need to emphasize that the visual inspection of the prepubertal and adolescent girl’s genitalia is a normal and expected part of a routine physical examination, much as a testicular examination is in boys. The gynecologic examination provides an opportunity to educate both the parent and child on hygiene and preventive care, and to give correct anatomic names for private parts (so that the little girl’s vagina is not just a “hoo hoo” or “wee wee”). It also is a time to teach that private parts are private, setting the stage for dialogues on “stranger danger” and how to keep the child safe. The pediatric gynecologic examination requires a special degree of patience and communication, necessary to put both patient and parent(s) at ease during what can often be an anxiety-producing situation. Pediatric gynecologic examinations range from the normal look at a bottom during a routine pediatric well-child visit, which ideally should be anxiety free, to forensic examinations in cases of suspected abuse, where stress levels are high. The proper evaluation of the external genitalia is critical to the diagnosis of pediatric reproductive endocrine disorders such as precocious puberty. This chapter provides guidelines for how to perform an appropriate history and physical examination on the prepubertal child, including helpful hints on positioning the child (and parent) for visual inspection, necessary office equipment, and communication with both child and parent. Diagnosis and management of vulvovaginitis in the prepubertal child are covered, as well as recognition of lichen sclerosis and other dermatologic presentations of disease. Finally, strategies for recognition of sexual abuse and effects on hymenal anatomy in the prepubertal child are addressed, along with helpful hints for the child presenting with vaginal bleeding or a mass.
APPROACH TO THE PEDIATRIC GYNECOLOGY PATIENT There are several components to the evaluation of a pediatric gynecology patient, all of which may not occur at the initial consultation. If a problem is complex, the physical examination may have to be postponed to a subsequent office visit. There is a natural progression of events that needs to occur to establish a proper rapport with the child and parents.
Obtaining a History When evaluating a child in a routine office setting or in a specialized gynecologist’s practice, the clinician can ask the child directly if she has any worries or concerns about her body or health. If the child defers to the parent, the clinician can then direct questions to the parent or care provider while the child plays in the office or examining room. Having child-friendly toys and books available, with safety precautions such as electric socket covers for outlets, can help allow the child to relax in a safe way. Periodically, questions can be directed to the child to put the child at ease, focusing on toys, school, and other nonthreatening topics at first. The parent should be asked about their current specific concerns, along with background history of growth, development, and past problems. If the parent raises a specific gynecologic concern, the child can then be asked if she has pain or itching in her bottom or vagina. If sexual abuse is a concern, she should be asked if anyone has ever touched her “girl parts” or private parts, and asked, “Tell me about it.” Openended questions are most useful to prevent having answers influenced by the questioner. In trying to glean specific details, it may be necessary to ask whether she or anyone else has ever placed something in her vagina. All questions should be asked without stern or judgmental looks, with good eye contact maintained with the child; this approach helps to make the child feel that she is an important member of the team and gives her a chance to ask questions. In cases of abuse, it can also help prevent or minimize shame, guilt, and negative feelings that the child may be directing at herself.
Establishing Confidentiality With an older child (over age 10) with concerns of sexual abuse and with all adolescents, all questions regarding sexual history, vaginal discharge, and vulvar itching should be asked without a
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Section 2 Pediatric and Adolescent Disorders parent in the room. Adolescents are often loathe to answer questions honestly with a parent listening, especially if they are engaging in a risk behavior about which they don’t want the parents to know. Older children with suspected sexual abuse may not wish to disclose with the perpetrating parent or the spouse of the perpetrator present for fear of punishment at disclosure or for fear of not being believed, with consequences for “lying.” Establishing confidentiality provides an opportunity to ask questions directly of the child without the influence of the parents, with an expectation of honesty. The child or adolescent may still withhold the truth, often delaying to determine whether the clinician is “trustworthy” or if he/she can really help. Before establishing confidentiality, the clinician should obtain information on current concerns, past medical history, family illnesses, and other less personal questions, with the parent and the child together. The parent can then be asked if there are any private concerns he or she wishes to discuss without the child present. At this time, the clinician should clearly and concretely define confidentiality with both parent(s) and child present. One way to do so would be to state, “Everything I talk about alone with your parent is confidential, meaning I will not share with you any of your parents’ private concerns. In the same way, everything I talk about with you without your parent is confidential, meaning I will not share with them your private concerns. The only exception is if you or your parent tell me something life-threatening or dangerous; then, I would say, ‘we need to talk to your parent about this.’ ” When possible, getting parent confidential history before patient confidential history works better, because it guides you toward the parent’s immediate concerns sooner and also helps the child not feel “reported on.” The child also recognizes that you didn’t “spill the beans” or disclose the parent’s confidential concerns, building trust so that they do not feel the clinician will disclose the child’s private concerns. After confidentiality has been outlined/established, the child can be asked if she prefers the parent in the room or out of the room for the examination. If she prefers the parent in the room, the clinician can state, “I will take a few minutes with your daughter alone to address any of her private concerns. Then, we will bring you back in the room for the exam.” If the child prefers the parent to leave the room for the examination, confidential questions can be asked during the performance of the examination.
The HEADS Questions
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The major adolescent morbidities and mortalities stem from risk-taking behaviors rather than disease processes. Therefore, questions designed to elucidate those risk-taking behaviors in an expedient way can be used to avoid the “Oh By the Way” experience, or the major problem casually mentioned in the last few minutes allotted for a visit. A useful acronym for obtaining the psychosocial history from an older child or adolescent is HEADS.1,2 Table 13-1 outlines these questions, which are geared more toward the adolescent but can be modified into simpler terms for the child. With risk behaviors such as cigarettes or drugs, asking about peers’ or friends’ use can be particularly helpful with the older child or younger adolescent, because they may easily talk about others’ risk behaviors, which can then make it easier to talk about themselves.
Table 13-1 The HEADS Examination Home: Who lives in the home? What happens when there is an argument in the home? If father is not in the home, how often does the child see him? Does that feel like the right amount? In cases of sexual abuse, any boy babysitters? Any alone time with stepfathers, uncles, neighbors, cousins? Education: What grade is the child in? How are their grades this year? How were they last year? Activities: How does the child spend their time? Any sports, or other activities? For teens, are they in a gang or do they have access to a gun? Drugs: Do they know anyone who smokes cigarettes? Do they smoke cigarettes? How much, how often, what have they tried to quit? Do their friends use any drugs? If so, which ones? Have they tried any drugs? Do their friends drink alcohol? Have they tried alcohol? How much, how often, ever to the point of blacking out or passing out? D is also for depression: Ever been depressed? Ever to the point of wanting to hurt yourself? Have you tried to hurt yourself? Ever to the point of wishing you were dead? (passive suicidal ideation). Ever to the point of wanting to kill yourself? Have you specifically had a plan? Which plan(s)? Have you ever tried to kill yourself? Which ways? Sex: Have you ever had sex? Are you sexually attracted to guys, girls, or both? Sexually, has anyone ever touched you in a way that made you uncomfortable? Have you ever had to swap sex for food, clothes, drugs, or shelter?
If a teen perceives that all of her friends smoke, but she states that she does not smoke, the clinician can then ask what she says to her friends when they ask her to smoke with them. If the teen has no answer, the clinician has the chance to suggest an appropriate response (e.g., “I like my lungs the way they are” or “I choose not to smoke.”). Thus, the clinician can role-model responses without artificially setting up a role-play. This strategy represents a form of motivational interviewing or helping the teen build skills while obtaining the history. Similarly, with a younger child, the clinician can ask, while examining private parts, “What would you do if another adult or child wanted to look at or touch your private parts?” If the child has no response, the clinician can help guide her towards ways to keep herself safe, often providing the parent with strategies to initiate/ continue these educational moments. Asking questions in a nonjudgmental manner inspires confidence in the child and adolescent, increasing the likelihood that they will disclose sensitive information that may have an impact on their health. With adolescents, prior sexually transmitted diseases, vaginal discharge or odor, methods of contraception used, menstrual history, and other related questions should also be asked confidentially.
The Gynecologic Examination Itself: The Rules The genital examination of the child should be approached with special verbal acknowledgement to the child and parent before requesting the child to disrobe. With the younger child at preventive healthcare visits, the clinician can state that he/she will look at her bottom every year to make sure that everything is okay, reminding the child and parent that this part of the examination is an expected and routine part of every well-child visit. With younger children, it is useful to state, “It is okay if a doctor looks at your private parts with your mommy here, but it’s not okay if anyone else looks at your private parts without your mommy’s permission. If anyone ever did that, what would
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Chapter 13 Pediatric Gynecology you do?” If the child does not respond, often the parent will chime in, “Oh, she knows about strangers, tell the doctor what you know.” Give positive feedback for whatever response the child gives, especially if the child states that she would tell mommy (and the doctor and the police). If the child does not respond or does not say that she would tell mom, the clinician needs to state that it is very important for her to tell her mommy and/or the doctor so that we can keep her safe and healthy. The clinician can further elaborate on stranger danger, stating that sometimes strangers or even people the child might know can try to scare her into silence, telling her that she must not tell when something bad has happened. The clinician can then state that telling is the best way to have us protect the child, and that the bad person keeps power only through the child’s silence, or not telling. In cases of abuse, this can be a sophisticated concept that can be put into understandable terms for the child. The examination can also be used to educate the child on the rules of hygiene. For instance, the clinician can state, “I want to talk to you about the rules. One rule is that you don’t let poop get near your girl parts. That is why we wipe from front to back (demonstrating), so that the poop stays away from where you tinkle.” (Other phrases can be substituted, but here layman’s terms tend to be more useful than elimination, voiding, and other more medically accurate terms; the point is to have the child understand the concept). A mirror can be used to teach a child how to wipe correctly after elimination and to show her which parts are where. Education on avoidance of bubble bath can also be reiterated, teaching parents to use baby shampoo rather than bubble baths that may cause a chemical irritation (bubble bath vaginitis). As the clinician performs the examination, he or she should state clearly what he or she is doing, describing findings and using words like “normal,” “perfect,” and “everything is in the right place.” The patient’s comfort remains the priority, with the child feeling in total control over the examination. The clinician must promise not to hurt the child or to cause any pain, and should keep that promise! Parents often have misconceptions about the hymen. Before and during the examination, the clinician can teach the parents that hymens come in varying shapes and sizes, and that the examination will not harm or “break” the hymen in any way. Use of a diagram can help educate the parent or child about normal female anatomy and can help clear up any misconceptions (Figs. 13-1 and 13-2). Because not all clinicians routinely inspect genitalia despite national recommendations that it should be part of the annual examination, parental anxiety may set a tone for the child. The clinician can educate both parent and child while allaying anxiety and teaching parents to send calming cues to their child, helping reassure the child rather than raise anxiety. Occasionally, this may require more than one visit to complete a gynecologic examination. Use of “tricks” such as hiding behind drapes, use of headphones, or murals on the ceiling should be avoided, because they may not allow a child to feel in control of the examination and be an active participant, thus destroying a child or parent’s confidence in the clinician. Rather, a straightforward approach with both parent and child can allow for proper examination while maximizing educational moments for both the parent and child.
Skin folds of mons pubis Clitoral hood (prepuce) Clitoris
Labia majora (undeveloped) Anterior vestibulum
Urethra
Labia minora Vaginal orifice
Posterior vestibulum Figure 13-1
A
Normal female anatomy in the prepubertal child.
B
E
Hymen
C
F
D
G
Figure 13-2 Various hymenal configurations. A, Normal posterior crescentic appearance. B, Normal annular hymen. C, Hymen with redundant or fimbriated appearance. D, An imperforate hymen. E, A microperforate hymen. F, A cribriform hymen. G, A septate hymen.
Helping the Child Feel in Control Attention to the little things can help a child feel in control. Rather than asking if the child wants to be in a gown, asking, “Do you prefer the green gown or the yellow one?” allows the child some autonomy in the process. The otoscope or hand lens can be used for magnification; allowing the child to look through the lens to see how it works can help put her at ease. If a
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Section 2 Pediatric and Adolescent Disorders colposcope will be used, letting the child view jewelry or fingers through the instrument and showing her how the light turns on and off can demystify the examination. Asking the older child if she prefers the parent in or out of the room can also help the child feel in control. Most children are comfortable lying on the examination table with a parent close by. If a child appears anxious, the clinician can ask if the child prefers to be a big girl on the table herself or to lie in the parent’s lap for the examination to help the child maintain control. The parent can then be placed in a semireclining position on the examination table with the parent’s feet in the stirrups and the child’s legs straddling the parent’s thighs. Even a father can be taught to assume this position, with the child on his lap—often as more of a challenge for him than for his child! If necessary, this position can be tried with the patient in clothes before performing the actual examination. A handheld mirror can be used to educate the patient (and parent) on normal anatomy while providing a means of recruiting the child as an active participant. The child can also maintain control by being asked to assist in holding her labia apart. If the clinician acts relaxed and confident, the patient (and parent) will usually cooperate.3 An abrupt or hurried approach may lead to a child’s refusal to continue, so patience and a calm, confident tone are required. If a child needs more time, the examiner can leave the room until the patient feels ready. Several visits may be necessary to set the child at ease and build confidence that she will not be hurt. If an acute need for an examination exists, as in the case of vaginal bleeding, often an examination under anesthesia may be necessary.
The Actual Examination
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Examination of the child with gynecologic complaints should include measuring height, weight (and body mass index if obese), performing a visual inspection from head to toe, including head, neck, heart, lungs, abdomen, Tanner staging (see Chapter 11), breasts (inspection and palpation for masses or discharge), and skin for rashes/lesions. A simple way to remember Tanner staging is as follows. For pubic hair, Tanner I means prepubertal, or no hair. Tanner II hair is fine and downy, and you can count them. Tanner III hair is coarse, in a triangular pattern, and you can count them if you are obsessivecompulsive! Tanner IV pubic hair means too many to count, and Tanner V means out to the thighs. For breast development, Tanner I means no bud yet, or prepubertal. Tanner II means just a breast bud under the nipple. Tanner III extends beyond the nipple, and Tanner IV is a mound of areola on top of a mound of breast. Tanner V refers to adult breasts, with the areola now flush with the breast but the nipple protruding. Gynecologic assessment includes inspection of the external genitalia, palpation of the inguinal area for hernias or masses, and visualization of the vagina. Hymenal anatomy should be noted and documented in the medical record (see Figs. 13-1 and 13-2). Hymens come in different configurations, with many variants of “normal.” Hymens can be classified as crescentic or posterior rim, annular, or redundant.3,4 Recognition of an imperforate hymen before puberty is generally greatly appreciated by parents, so that anticipatory guidance can be given and an easy procedure accomplished before menstrual flow
accumulates behind a blocked passageway. Cribriform or microperforate hymens and septate hymens can also be confusing to the untrained eye; pictures of each are seen in Figure 13-2. Further subtleties of the hymenal examination are addressed in the section Approach to the Child who Has Been Sexually Abused. For a complete gynecologic examination, rectoabdominal palpation should be performed and the cervix should also be visualized. For the younger child, the latter can usually be performed in frogleg position, either on or off the parent’s lap. If, however, the hymen cannot be fully assessed or concerns about the presence of a foreign body exist, the child can be placed in knee-chest position. The child can be told that she should lie on her tummy with her bottom in the air, “just as you may have done when you were a baby sleeping.” The parent or the child herself can be recruited to spread the buttocks gently, and an otoscope can be used on the outside to illuminate the area. Two thirds of the vagina and even the cervix may be visualized in this manner. Often foreign bodies such as bits of toilet paper can be identified with the child in this position. A butterfly catheter of any size with the needle cut off can be attached to a tuberculin syringe with 1 μL of saline, and then placed inside a 12-inch red rubber bladder catheter to irrigate or wash off the genitalia.5 This catheter within a catheter can be squirted on the patient’s hand or thigh, so as not to surprise her, with explanation that it may feel cold and wet, allowing the area to be irrigated easily. During the gynecologic examination, the clinician should note the presence of pubic hair, the size of the clitoris, hymenal configuration, signs of estrogenization of the vagina and hymen, and perineal hygiene.3 A clitoris larger than 10 mm in a pubertal girl is considered enlarged. The clitoris in the premenarchal child averages 3 mm in length and 3 mm in transverse diameter.6 If the hymen is viewed in lithotomy or frogleg position and likened to the face of a clock, irregular notching or transactions of the hymen between 5 and 7 o’clock are suggestive of sexual abuse, forced sexual intercourse, or trauma. If the hymenal orifice and edges cannot be easily visualized in this position, the labia can be gently gripped and pulled forward with gentle traction. The child can be asked to cough or take a deep breath and hold it for a few seconds, allowing the hymen to gape open. In the prepubertal girl, the vaginal mucosa tends to be red, thin, with erythematous perihymenal tissue. In the pubertal girl, the mucosa becomes dull pink and moist under the influence of estrogen. Estrogenized tissues tolerate instrumentation better than do atrophic or prepubertal tissues. With the development of secondary sexual characteristics, the teen girl needs to hear that she is normal, even if she has been subjected to past sexual abuse. Sexual activity can cause friction, trauma, or infection, along with exposure to irritant or contact dermatitis if the teen is allergic to latex or sensitive to a particular spermicide or lubricant. Issues of hygiene and grooming can cause problems, with irritation from shaving, waxing, or laser hair removal. Ornamentation or body piercing can also be a source of infection or scarring. Genital mutilation can still occur in various countries and be a source of shame plus physical discomfort. The rules for evaluating all girls still apply: if you don’t look, you won’t find. In the adolescent, inspection of the genitalia allows for identification of normal versus abnormal medical findings,
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Chapter 13 Pediatric Gynecology including folliculitis or “razor burn” in patients who shave or use other means of hair removal (usually noninfectious). Candidal vulvovaginitis can also be seen and may be the first presenting sign of diabetes. In patients who present repeatedly with yeast vaginitis, a urinalysis can rule out diabetes, and a culture on bismuth sulfate (BiGGY) agar can determine whether Candida is the offending organism. Visual inspection allows the opportunity to educate the adolescent in tampon use and in proper hygiene techniques; it may also elicit questions that the teen may have been too embarrassed to ask about (e.g., clitoral size, irregularities in size or shape of labia). A “lump” felt by a teenager may be a Bartholin’s cyst rather than perceived cancer.
Specialized Techniques for the Gynecologic Examination A small vaginoscope, cystoscope, hysteroscope, or flexible fiberoptic scope with water insufflation of the vagina can be used when knee-chest or lithotomy position does not provide sufficient visualization.3 Capraro first described a step-by-step approach for insertion of the vaginoscope in a young child.7 The child is first allowed to touch the instrument and told that it feels “slippery, funny, and cool.” The instrument is then placed against her inner thigh, repeating the same phrase, and then against her labia, with the physician again stating, “This feels slippery, funny, and cool.” As the vaginoscope is inserted through the hymen, the clinician repeats the same words while firmly pressing the child’s buttocks with the other hand to divert her attention.3 Lidocaine jelly or EMLA cream may be used at the introitus to ease insertion. A Killian nasal speculum with an attached fiberoptic light source or a narrow veterinary otoscope speculum can also be used; the former may not be long enough to visualize the upper aspect of the vagina.8 Office supplies should include kits to test for Neisseria gonorrhoeae and Chlamydia trachomatis, including both culture media/swabs for cases of sexual abuse and nucleic acid amplification test (e.g., GenProbe) for nonabuse cases. Slides, microscope (when permitted by CLIA), saline solution, and 10% potassium hydroxide (KOH) should also be available for use performing wet preps to visualize trichomonads and clue cells, and yeast with KOH. Some clinicians’ offices are not cleared for microscope use; in that case, vaginal swabs for Trichomonas, yeast, and bacterial vaginosis have been shown to be efficacious.9 Having 5% acetic acid available can be useful to identify the gray-white changes of human papillomavirus, and tests for herpes simplex virus should also be available. Newer methods such as DNA probes remain inconsistently accepted evidence in court cases of suspected sexual abuse. Cotton-tipped applicators and small nasopharyngeal calcium alginate-tipped applicators should be available. For the adolescent patient undergoing a first pelvic examination, the kind clinician uses the smaller Huffman speculum; for sexually active adolescents, the medium-sized Pedersen speculum is acceptable. Only multigravida or morbidly obese patients should require the wider Graves speculum. With a very obese patient, a fingertip of a glove can be cut off, with the glove finger then placed over the speculum blades, preventing the vaginal sidewalls from involuting and obscuring the view of the cervix.
If a vaginal discharge is present in a prepubertal child, cultures can be obtained using a nasopharyngeal Calgiswab moistened with nonbacteriostatic saline. Individual ampules of nebulized saline solution may be kept for convenient office use.3 In obtaining the sample, the clinician should avoid touching the hymenal edges, because the child may find those areas to be particularly sensitive. Asking the child to cough during this part of the examination can both distract the child and allow for the hymen to gape open for a quick swab. The catheter-in-acatheter technique described earlier can also be useful for sampling vaginal secretions. A Dacron male urethral swab scraped along the vaginal wall can be obtained and directly plated for a Chlamydia culture.3 Muram describes a technique of squirting saline with an Angiocath (needle removed) to fill the vagina followed by holding three swabs perpendicular just outside the vagina with the examiner holding the labia closed over the swabs. The child is asked to cough hard to expel the solution, and the wet swabs can then be used for the needed tests.3 Adolescents who do not require a pelvic examination can still be screened for C. trachomatis and N. gonorrhoeae using urine samples sent for nucleic acid amplification tests (e.g., GenProbe). In amenorrheic adolescent girls, a vaginal smear can be obtained to assess estrogenization. A saline-moistened cottontipped applicator or moistened Calgiswab can be inserted through the hymenal opening and scraped along the upper lateral sidewall of the vagina.3 If a speculum is being used, the sample can be obtained at that time. The swab is then rolled onto a glass slide, and the slide is sprayed with Pap fixative. The cytologist reads the smear, determining percentages of: parabasal, intermediate, and superficial cells. Parabasal cells are given a score of 0, intermediate cells 0.5, and superficial cells, which are associated with estrogenization, a score of 1. A score of 0 to 30 is seen in prepubertal girls, 50 to 60 in normal pubertal girls, 31 to 50 in hypoestrogenic patients, 60 to 70 in newborns (from maternal estrogen), and 90 to 100 in hyperestrogenic patients. Of course pregnancy should always be considered in the amenorrheic patient. Urine pregnancy tests should be available routinely in the office and emergency department (ED) setting. These highly sensitive, rapid pregnancy tests can detect human chorionic gonadotropin levels of 25 mIU/mL or more, or should be positive 7 to 10 days after conception. Patients who have been sexually active and conceived within the week before the urine pregnancy test may have a false-negative test. It may be necessary to follow up with the patient to verify that a period has occurred.
Screening Interval Sexually active adolescents should be screened 3 to 6 months after every new partner, with a first pelvic examination within 3 years of initiating sexual activity or by age 21, according to the latest American Cancer Society recommendations.10 Hormonal contraception per se does not mandate a pelvic examination or Papanicalou (Pap) test; linking prescriptions for hormonal contraception to an annual pelvic examination can be an insurmountable barrier to a teenager, resulting in unplanned teen pregnancy.3,11 Adolescents often equate a pelvic examination
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Section 2 Pediatric and Adolescent Disorders with Pap smear; if her examination was performed in an ED setting, where Pap smears are not obtained routinely, she may have never received screening for cervical cancer or human papillomavirus. Immunosuppressed girls and teens with multiple partners may require more frequent screening.
APPROACH TO THE CHILD WITH SUSPECTED VULVOVAGINITIS Poor hygiene, lack of estrogenization, proximity of the vagina to the anus, and lack of protective hair and labial fat pads contribute to the frequency of vulvovaginitis in the prepubertal child. Nylon tights and underwear, wet bathing suits worn poolside or at the beach, close-fitting jeans, and sweating may cause nonspecific vulvar itching or overgrowth of yeast, which prefers to grow in moist areas such as the vagina or folds of the groin. Bubble baths and perfumed soaps may cause a chemical irritation.
Infectious Causes
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Pinworms (Enterobius vermicularis) can be found in this age group, with ova easily visualized by pressing scotch tape onto the perianal skin for several seconds, then transferring it onto a slide. Parents may see adult pinworms using a flashlight in the middle of the night to illuminate the perianal area. When diagnosed, pinworms are easily treatable with 100 mg of mebendazole. Nonspecific vaginitis accounts for 25% to 75% of cases of vulvovaginitis evaluated at referral centers.12–16 Candida, Peptostreptococcus, and Bacteroides species have been found more commonly in girls with vaginal discharge and/or with vulvovaginitis than in asymptomatic girls.16 In a study of 80 prepubertal girls aged 2 to 12 with vulvovaginitis, pathogenic bacteria were isolated from vaginal swab in 36% of cases, with 59% of this group positive for group A β-hemolytic streptococci.17 The presence of leukocytes in vaginal secretions was associated with the finding of pathologenic bacteria, with a sensitivity of 83% and a specificity of 59%. Pathogenic bacteria can include group A β-hemolytic streptococci (Streptococcus pyogenes), Haemophilus influenzae, Staphylococcus aureus, Moraxella catarrhalis, Streptococcus pneumoniae, Neisseria meningitides, Shigella, and Yersinia entercolitica.3,17 Vaccination against H. influenzae may be having the unplanned positive effect of lowering the incidence of vaginitis caused by that organism. E. coli was found in the vagina of 36% of girls presenting with vaginitis and in 23% of asymptomatic girls.18 Ninety percent of girls under age 3 had E. coli vaginal colonization, as compared to 15% of 3- to 10-year-old asymptomatic girls.19 In one case report, a prepubertal girl was diagnosed with a prolonged course of vulvovaginitis caused by antibiotic-resistant Shigella flexneri.20 After 3 years of intermittent vaginal bleeding, dysuria, and foul smelling vaginal discharge, unsuccessfully treated with ampicillin, trimethoprim-sulfamethoxazole, cefixime, and amoxicillin/clavulinic acid, symptoms finally resolved with a 14-day course of ciprofloxacin. Bloody discharge is less common in this age group and should warrant culture in the prepubertal child.20,21 Patients may present with or without recent diarrhea.
Noninfectious Causes A majority of cases of vulvovaginitis in the prepubertal age group are noninfectious; when infectious in etiology, symptoms tend to include more severe inflammation and vaginal discharge.12 Given the great overlap between normal flora and potential pathogens, a positive culture may or may not indicate infection.12 If a young girl presents with green vaginal discharge and no foreign body is found (a common cause, mainly with toilet paper as the offending object), and the culture grows predominantly one organism, infection should be considered and appropriately treated. Cultures should be obtained when visible or profuse discharge is noted and in patients with moderate to severe inflammation. Treatment usually will consist of sitz baths and removal of offending agents (foreign body locally; environmental irritants such as bubble bath or cleaning solution overly aggressively applied and not rinsed out of the bathtub). Sexual abuse is a rare cause of vulvovaginitis, but should be considered when specific patterns of injuries occur or with suspicious histories.
APPROACH TO THE CHILD WHO HAS BEEN SEXUALLY ABUSED Acquired abnormalities of the hymen can be the result of either sexual abuse or, more rarely, accidental trauma. Tampon use rarely will cause lacerations of the hymen.22 Signs of acute trauma with sexual abuse can include hymenal transections, hematomas, abrasions, lacerations, and vulvar erythema or irritation. Physical healing after trauma occurs quickly, with complete resolution often by 10 to 12 days.3 Although a hymenal notch, remnant, or scar may be visualized, most girls with a history of substantiated sexual abuse have a completely normal examination.3 Appropriate testing in cases of sexual abuse include a culture for N. gonorrhoeae on modified Thayer-Martin-Jembec medium, with the bacteriology laboratory notified that the specimen is from the vagina of a prepubertal child, so that if a Neisseria species grows, it is properly and unequivocally identified as N. gonorrhoeae for medicolegal purposes.3 Bacterial isolates initially identified as N. gonorrhoeae from children may be other species such as N. lactamica, N. meningitidis, and N. cinerea.23,24 Culture tests for C. trachomatis should be used in the diagnosis of prepubertal infections, especially because falsepositive results can occur with some nonculture tests. If culture is not available, nucleic acid amplification tests (NATs) are acceptable if another NAT that targets a different sequence can be performed if the first NAT test is found to be positive.3,25,26
APPROACH TO THE CHILD WITH VAGINAL BLEEDING Vaginal bleeding in the prepubertal child requires a sensitive approach and careful assessment. In the newborn, vaginal bleeding usually represents withdrawal from maternal estrogen and can be impressive to the clinician or parent, with the passing of clots. After the initial newborn period, the differential diagnosis expands, with foreign body near the top of the list, and including sexual abuse, lichen sclerosis, vulvovaginitis, precocious puberty, and tumors. Other conditions causing vaginal bleeding
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Chapter 13 Pediatric Gynecology include urethral prolapse, hemangiomas, and condyloma (although the latter rarely bleed). Questions for the parent and child include timing and duration of the bleeding, any history of trauma, hematuria, rectal bleeding, symptoms of vaginitis, pubertal development, and potential abuse. Pubertal findings in a child under age 7 or 8, especially with accelerated linear growth, may indicate precocious puberty. Patients with thrombocytopenia are likely to have evidence of bleeding elsewhere, as in petechiae, easy bruising, or epistaxis.3 On close physical inspection, hymenal tears or injuries of the posterior fourchette should be strongly suspicious for abuse. In contrast, straddle injuries tend to produce labial or perineal hematomas. With a significant injury causing a large hematoma, ice packs should be applied immediately, and the child should be watched for urine retention; a Foley catheter may need to be inserted for urinary drainage before further swelling distorts genital anatomy. Significant bleeding may require an examination under anesthesia to clarify findings and stop bleeding acutely. With more minor bleeding, 2% lidocaine jelly or EMLA cream can be used over the cut, with warm water in a syringe used to irrigate the injury gently. The parent or child can assist by applying cool compresses with pressure. Gelfoam or Surgicel can be applied to areas still oozing.
OTHER GENITAL FINDINGS IN PREPUBERTAL CHILDREN Labial Adhesions Labial adhesions are relatively common in children. The labia minor or majora can agglutinate to a variable extent from clitoris to the posterior fourchette, partially or completely obstructing urine flow. A secondary dermatitis from pooling urine or vaginal secretions can occur infrequently, with urinary tract infection found occasionally. Most children are asymptomatic, with the adhesions bothering the parent more than the child. Labial adhesions are easily treatable with topical estrogen cream (Premarin) applied directly to the area in tiny amounts daily. Because the skin of this area is constantly exposed to chronic irritants, adhesions can easily recur. Parental education must include preventive measures such as minimizing exposure to chronic irritants and the use of appropriate protective emollients. It is also important to educate the parents on how not to use too much estrogen to avoid systemic secondary effects. It is uncommon to require mechanical separation of the adhesions. If it becomes necessary to separate the adhesions surgically, then appropriate anesthesia should be provided.
Lichen Sclerosis et Atrophicus Lichen sclerosis et atrophicus is found in prepubertal children and postmenopausal women. This disorder is associated with a hypoestrogenic state. Girls tend to present with itching, soreness, vaginal or perineal bleeding, dysuria, and more rarely with constipation. This is a diagnosis where a picture is worth a thousand words; the classic hourglass or figure of 8 demarcation of hypopigmented skin from above the clitoris to the anus with scattered telangiectasia is classic, with or without fissuring of the perineum. Midpotency to stronger topical corticosteroids
usually work initially, with the goal of providing relief with the lowest steroid formulation possible. Midpotency steroids include hydrocortisone valerate 0.2% (Westcort); high-potency steroids include fluocinonide 0.05% (Lidex). Rarely, a patient will need a superpotent steroid, such as clobetasol proprionate 0.05% (Temovate) or halobetasol proprionate 0.05% ointment (Ultravate). Ointments tend to sting less than creams. Emollients such as Vaseline or aquaphor can also help. The steroid cream is usually applied sparingly twice a day for 2 weeks, then once a day for 2 to 4 weeks, and then every other day for 2 weeks. With chronic use of steroids, the clinician and patient/family must watch for atrophy, telangiectasias, striae, hypopigmentation, and superinfection (fungal or viral). Close follow-up and ongoing education can help minimize both recurrences and the sequelae of overaggressive steroid use.
Atopic Dermatitis A few children may be sensitive to various diaper creams, wipes, or to a specific brand of diapers themselves. In these children, the perineal area will be brightly erythematous without the satellite lesions common with candida. A simple brand change will usually suffice; in extreme cases, wiping with water on a washcloth rather than using commercially available wipes may be necessary. Given the moist nature of the diaper area, typical atopic dermatitis tends to spare the diaper area until the child is out of diapers. Once toilet trained, the child may scratch at the buttocks or perineum enough to cause superinfection with S. aureus or Streptococcus species; S. aureus infection rarely involves the vagina.27 Use of emollients, hypoallergenic soaps (e.g., Aveeno, Lever 2000, Dove, Neutrogena), and light-handed use of 1% hydrocortisone cream will usually relieve symptoms. Parents need to be taught not to overuse steroid creams to avoid creation of atrophic areas.
Psoriasis More common in the vulvar area in children than in adults, psoriasis may present as an itchy, well-demarcated, brightly erythematous, nonscaly symmetric plaque involving the vulva, perineum, and gluteal folds. On close examination, the child may have evidence of nail pitting, posterior auricular erythema, or rash elsewhere with scaling. Simple use of 1% hydrocortisone may not work except as maintenance therapy; start with lowpotency to midpotency topical corticosteroids, increasing in strength if necessary to induce a response. Concurrent infection needs to be treated.
Systemic Diseases Common illnesses such as infectious mononucleosis can present with uncommon findings, such as vulvar ulcers that can mimic herpes simplex virus.27,28 Kawasaki syndrome can be accompanied by desquamation of the perineum, as can StevensJohnson syndrome. Crohn’s disease is more likely to involve the perianal area than the vulvar area. Rarely seen in pediatrics, Behçet’s disease is an autoimmune response characterized by the clinical triad of iridocyclitis, oral ulceration, and genital ulceration. Other findings include retinal vasculitis, optic atrophy, meningoencephalitis, proteinuria and hematuria, thrombophlebitis, aneurysms, and arthralgias. With a prevalence
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Section 2 Pediatric and Adolescent Disorders ranging from 1:10,000 in Japan to 1:500,000 in North America and Europe, Behçet’s syndrome usually starts with oral apthous ulcers, with genital ulcers often occurring over time and ocular symptoms starting usually in the teenage years.27,29,30 Again, ulcers and excoriation of the vulva may mimic herpes simplex virus infection and cause pain and/or embarrassment to the child, adolescent, and parent. Zinc deficiency can be associated with acrodermatitis enteropathica, or perioral cracking, along with an eroded bilateral vulvar rash with a well-demarcated edge.31,32
Genital Tumors Although rare, genital tumors should be considered in any girl presenting with chronic genital ulceration, nontraumatic swelling of the external genitalia, protrusion of a mass from the vagina, foul-smelling bloody discharge and no evidence of foreign body, or virilization or precocious puberty. Embryonal carcinoma of the vagina (botyroid sarcoma) is found more commonly in young children, with a peak incidence in 2 year olds, and 90% of cases occurring in children under age 5. In younger children, the tumor is often found in the lower vagina, in contrast to tumors of children over age 10, in whom the tumor more often affects the upper vagina or cervix.27 Originating in the lamina propria from undifferentiated mesenchyme, the tumor spreads rapidly below the vaginal epithelium, infiltrating the vaginal wall, bulging outward with polypoid growths containing edematous stroma and dilated blood vessels. Thus, the tumor takes on a cluster-of-grapes appearance. Chemotherapy and conservative surgery, with or without radiation therapy, has resulted in a survival rate of 80% to 90% in girls with localized pelvic rhabdomyosarcoma.3,33,34 Vulvar melanomas are rare but malignant. Langerhans’ cell histocytosis may involve the genital area. Congenital perineal lipomas can be found, as well as masses that do not represent tumors such as urethral prolapse, condyloma accuminata, prolapsed ectopic ureterocoele, and other more rare conditions.
CONCLUSION The prepubertal examination gives a time to educate the patient and parent on normal findings and hygiene, as well as to inspect for disease or potential abuse. Patience combined with a
child-oriented approach can make this examination tolerable to most children and their potentially anxious families; several visits may be required in the case of a very fearful child or one who has faced genital trauma. Sexual abuse needs to be considered when relevant, both to detect real harm to the child and to prevent overdiagnosis of abuse when it truly has not occurred. Virtually any vulvar condition may be mistaken for sexual abuse by parents and clinicians not accustomed to seeing the various vulvar disease that present in childhood. Vulvar dermatologic problems in girls remain very common, very uncomfortable emotionally and physically to the child and parent, and may be neglected due to embarrassment or fear on the part of the child. Lichen sclerosis, Behçet’s disease, and acquired anomalies such as labial adhesions require careful education of parent and child, when of toddler age and above, to reassure, help them feel “normal,” and prevent/treat recurrence of symptoms. Simple rules for diagnosis and treatment of infection prevail: (1) If there’s pus, culture it. (2) If there’s an abscess, incise and drain it. (3) Treat systematically and topically. (4) Warm soaks help. Most prepubertal gynecologic problems will not require instrumentation but can be handled with simple strategies for close visual inspection, cultures when appropriate, simple flushing for foreign body removal, and time spent on education and prevention.
PEARLS ●
●
●
●
●
●
●
The examination of a prepubertal child should include the Tanner staging. The normal hymen has a varied appearance and the absence of an anterior part (crescent shape) does not signify sexual abuse. The majority of cases of vulvovaginitis in the prepubertal child are noninfectious. Nonspecific vaginitis accounts for 25% to 75% of cases seen in prepubertal children. Pathogenic bacteria were isolated in 36% of cases of vulvovaginitis and over half were group A streptococcus. Labial adhesions are treated with topical estrogen and although commonly recurrent do not require surgical therapy. Lichen sclerosis is treated with topical steroids.
REFERENCES
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1. Goldenring JM, Cohen E: Getting into adolescent heads. Contemp Pediatr July: 75–90, 1988. 2. Goldenring JM, Rosen DS: Getting into adolescent heads: An essential update. Contemporary Pediatrics 60:28–30, 2004. 3. Emans SJ, Laufer MR, Goldstein DP: Pediatric and Adolescent Gynecology, 5th ed. Philadelphia, Lippincott Williams & Wilkins, 2005. 4. Pokorny SF: Configuration of the prepuberatal hymen. Am J Obstet Gynecol 157:950–956, 1987. 5. Pokorny SF, Stormer LVN: Atraumatic removal of secretions from the prepubertal vagina. Am J Obstet Gynecol 157:950–956, 1987. 6. Huffman JW, Dewhurst CJ, Capraro VJ: The gynecology of childhood and adolescence. Philadelphia, WB Saunders, 1981. 7. Capraro VJ: Gynecologic examination in child and adolescents. Pediatr Clin North Am 19:511–528, 1972. 8. Hairston L: Physical examination of the prepubertal girl. Clin J Obstet Gynecol 40:127–134, 1997.
9. Blake DR, Duggan A, Quinn T, et al: Evaluation of vaginal infections in adolescent women: Can it be done without a speculum? Pediatrics 102:939, 1998. 10. Saslow D, Runowicz CD, Solomon D, et al: American Cancer Society guideline for the early detection of cervical neoplasia and cancer. CA Cancer J Clin 52:342, 2002. 11. Stewart FH, Harper CC, Ellertson CE, et al: Clinical breast and pelvic examination requirements for hormonal contraception: Current practice vs evidence. JAMA 285:2232, 2001. 12. Jaquiery A, Stylianopoulos A, Hogg G, Grover S: Vulvovaginitis: Clinical features, aetiology, and microbiology of the genital tract. Arch Dis Child 81:64–67, 1999. 13. Paradise JE, Compos JM, Friedman HM, et al: Vulvovaginitis in premenarchal girls: Clinical features and diagnostic evaluation. Pediatrics 70:193, 1982. 14. Emans SJ, Goldstein DP: The gynecologic examination of the
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15. 16. 17. 18.
19.
20.
21. 22.
23. 24.
prepubertal child with vulvovaginitis: Use of the knee-chest position. Pediatrics 65:758, 1980. Heller RH, Joseph JH, David HJ: Vulvovaginitis in the premenarchal child. J Pediatr 74:370, 1969. Pippo S, Lenko H, Vuento R: Vulvar symptoms in paediatric and adolescent patients. Acta Paediatr 9:431, 2000. Stricker T, Navratil F, Sennhauser FH: Vulvovaginitis in prepubertal girls. Arch Dis Child 88:324–326, 2003. Gerstner GJ, Grunberger W, Boschitch E, et al: Vaginal organisms in prepubertal children with and without vulvovaginitis. Arch Gynecol 231:247, 1982. Hammerschlag MR, Albert S, Rosner I, et al. Microbiology of the vagina in children: Normal and potentially pathogenic organisms. Pediatrics 68:57, 1978. Baiulescu M, Hannon PR, Marcinak JF, et al: Chronic vulvovaginitis caused by antibiotic-resistant Shigella flexneri in a prepubertal child. Pedatr Infect Dis J 21:170–172, 2002. Murphy TV, Nelson JD: Shigella vaginitis: Report of 38 cases and review of the literature. Pediatrics 63:511–516, 1979. Emans SJ, Woods ER, Allred EN, Grace E: Hymenal findings in adolescent women: Impact of tampon use and consensual sexual activity. J Pediatr 125:153, 1994. Alexander ER: Misidentification of sexually transmitted organisms in children: Medicolegal implications. Pediatr Infec Dis J 7:1, 1988. Whittington WL, Rice RJ, Biddle JW, et al: Incorrect identification of Neisseria gonorrhoeae from infants and children. Pediatr Infect Dis J 7:3, 1988.
25. Centers for Disease Control and Prevention: Screening tests to detect Chlamydia trachomatis and Neisseria gonorrhoeae infections 2002. MMWR 51(RR-15):1, 2002. 26. Centers for Disease Control and Prevention: Sexually transmitted diseases treatment guidelines 2002. MMWR 51(RR-6):1, 2002. 27. Mroueh J, Muram D: Common problems in pediatric gynecology: New developments. Curr Opin Obstet Gynecol 11:463–446, 1999. 28. Sisson BA, Glick L: Genital ulceration as a presenting manifestation of infectious mononucleosis. J Pediatr Adolesc Gynecol 11:185–187, 1998. 29. Uziel Y, Brik R, Padeh S, et al: Juvenile Behçet’s disease in Israel. The Pediatric Rheumatology Study Group of Israel. Clin Exp Rheumatol 16:502–505, 1998. 30. Elem B, Onur C, Ozen S: Clinical features of pediatric Behçet’s disease. J Pediatr Ophthalmol Strabismus 35:159–161, 1998. 31. Fischer GO: Vulvar disease in pre-pubertal girls. Australas J Dermatol 42:225–236, 2001. 32. Stapleton KM, O’Loughlin E, Relic JP: Transient zinc deficiency in a breast-fed premature infant. Australas J Dermatol 36:157–159, 1995. 33. Copeland LJ, Gershenson DM, Saul PB, et al: Sarcoma botyroides of the female genital tract. Obstet Gynecol 66:262, 1985. 34. Arndt CA, Donaldson SS, Anderson JR, et al: What constitutes optimal therapy for patients with rhabdomyosarcoma of the female genital tract. Cancer 91:2454, 2001.
USEFUL WEB SITES The Center for Young Women’s Health, Children’s Hospital, Boston, provides a useful site for clinicians, educators, parents, and youth, at www.youngwomenshealth.org For hymenal anatomy: www.youngwomenshealth.org/hymen.htm American College of Obstetrics and Gynecology (ACOG): www.acog.org Policy statements for professionals, educational materials for teens and families. American Academy of Pediatrics (AAP): www.aap.org Policy statements for pediatricians/health care professionals, educational materials for patients, with links to the Bright Futures web site: http://brightfutures.aap.org/web
American Medical Association (AMA): www.ama-assn.org/ama/pub/category 1979.html Adolescent-specific section with educational resources. The North American Society for Pediatric and Adolescent Gynecology (NASPAG): www.naspag.org Useful site for clinicians, including teaching slide set that is available for purchase.
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Section 2 Pediatric and Adolescent Disorders Chapter
14
Reproductive Disorders in the Adolescent Patient Marjan Attaran and Gita Gidwani
INTRODUCTION Consultations for adolescent reproductive disorders range in scope from simple reassurance to investigation of complex endocrine problems. The reproductive disorders usually focus on the menstrual period and deal with lack of a menstrual period, irregular cycles, or painful periods. Other medical or social problems such as eating disorders often have a profound impact on the diagnosis and management of the presenting problem. This chapter focuses on adolescent reproductive disorders. Many of the disorders discussed in this chapter are reviewed in more detail in other chapters that deal specifically with the disease. The purpose of this chapter is to highlight specific issues encountered in the adolescent population.
MENSTRUAL DISORDERS Menstrual disorders are a common complaint among adolescents. However, secondary to embarrassment, fear, or lack of knowledge, many adolescents never consult a gynecologist. The likelihood that these symptoms are caused by significant gynecologic pathology is low. However, the encounter provides an opportunity for the gynecologist to impart knowledge and empower the patient.
Dysmenorrhea In adolescents, the incidence of dysmenorrhea can be quite high and is often underreported or ignored by healthcare providers.1–3 In a survey of 2699 normal adolescents, the prevalence of dysmenorrhea was 59.7%.2 The authors noted that the prevalence of dysmenorrhea increased with age from 39% at age 12 to 72% at age 17. In a large Swedish epidemiologic study on adolescents with dysmenorrhea, 15% of responders reported disrupted daily activity secondary to severe dysmenorrhea.1 Although the severity of dysmenorrhea was enough to cause almost 51% of the respondents to miss school or work at least once, only 30% of respondents had mentioned this problem to their physicians. Thus, despite the high frequency of dysmenorrhea among adolescents, many do not seek help from their healthcare providers. Primary and secondary dysmenorrhea must be differentiated because management may vary significantly (Table 14-1). Primary dysmenorrhea is defined as menstrual pain that is not associated with a specific underlying pathology. Secondary dysmenorrhea is menstrual-associated pain that is due to an underlying pathologic process. History and pelvic examination are used to rule out secondary dysmenorrhea. Primary dysmenorrhea requires the
Table 14-1 The Gynecologic Differential Diagnosis of Pain with Menses Primary
Prostaglandin production abnormalities
Secondary
Endometriosis Pelvic inflammatory disease Ectopic pregnancy Missed abortion Uterine fibroids Outflow tract obstruction Ovarian cyst/mass Torsion Adenomyosis
initiation of ovulatory cycles. Thus, primary dysmenorrhea will present typically within the first 12 to 24 months after menarche. The onset, duration, and intensity of pain should be recorded. Cramps commonly begin on the first day of menses. The median duration of dysmenorrhea is 2 days.4 Typically, pain diminishes after the third day of bleeding. The patient may report associated symptoms of nausea, vomiting, low back pain, headache, diarrhea, dizziness, and occasionally fainting.5 The severity of dysmenorrhea appears to increase with the duration of menstruation.6 Certain features of the personal history may point the investigation in a particular direction. For example, a family history of endometriosis may increase the level of suspicion for this disease. The onset of pain with menarche raises the possibility of an obstructive müllerian anomaly. If the physical examination reveals cervical motion tenderness, adnexal masses, and increased uterine size the potential for pelvic infection or a pregnancy-related disorder such as an ectopic pregnancy is increased. If the patient has never been sexually active and the results of the examination are suboptimal, ultrasound should be performed. Laparoscopy is indicated only if clinical suspicion for secondary dysmenorrhea is high or if medical therapy for primary dysmenorrhea was unsuccessful. Pathogenesis of Dysmenorrhea
Release of prostaglandin F2α (PGF2α) from the secretory endometrium leads to myometrial contractions and subsequently primary dysmenorrhea (Fig. 14-1). Multiple studies have documented increased levels of PGF2α in the menstrual fluid and endometrial tissue of women who are dysmenorrheic versus eumenorrheic women.7,8 Release of prostaglandins into the circulation, typically within the first 48 hours from initiation of menses, accounts for some of the associated symptoms of nausea, headache, vomiting, and diarrhea.
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Section 2 Pediatric and Adolescent Disorders Endometrium cell wall Phospholipase A2
Arachidonic acid Cyclooxygenase
5-lipooxygenase
Cyclic endoperoxides
Leukotriene A4
LTC4 PGF2α, PGE2 LTD4
There is clear evidence that adolescents taking oral contraceptives have reduced rates of dysmenorrhea.12 Because depot medroxyprogesterone acetate (DMPA) inhibits ovulation and causes endometrial atrophy, it may be used to decrease dysmenorrhea symptoms in adolescents. However, the possible side effects—including osteoporosis—may limit its long-term use in adolescents. Dietary changes may impact dysmenorrhea. In a prospective, randomized, double-blind crossover study, 42 adolescents between the ages of 15 and 18 were given placebo or fish oil for 2 months.13 The results showed a significant reduction in dysmenorrhea in those who received the fish oil supplementation. This study seems to suggest that supplementation with omega-3 fatty acids may alleviate dysmenorrhea in adolescents. It has been suggested that omega-3 fatty acids prevent buildup of the more potent prostaglandins and leukotrienes that are associated with vasoconstriction and myometrial contractions.
Polycystic Ovary Syndrome LTE4 Myometrial contraction Vascular vasoconstriction
Ischemia Figure 14-1 Prostaglandin metabolism in the endometrium. Decrease in serum progesterone in the luteal phase results in the release of arachidonic acid from phospholipids in the cell membrane. PG, prostaglandin; LT, leukotriene.
The uterus can produce and metabolize leukotrienes (LT). Higher leukotriene levels are present in the myometrium and endometrium of adult women with dysmenorrhea.9 Levels of LTC4 and LTD4 have been found to be significantly higher in the menstrual blood of women with primary dysmenorrhea than in those without.10 Thus, these potent vasoconstrictors and inflammatory mediators may play a role in producing the symptom of dysmenorrhea. Treatment
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Many adolescents self-medicate, but it is typically in subtherapeutic doses. Lower doses of over-the-counter nonsteroidal antiinflammatory drugs (NSAIDs) have been used in conjunction with other modes of treatment such as local heat therapy, exercise, and herbal therapy. NSAIDs reduce prostaglandin production by inhibiting cyclo-oxygenase. Multiple studies have shown that NSAIDs reduce the severity of symptoms associated with dysmenorrhea.11 A clear advantage of one NSAID over another has not been demonstrated. If NSAIDs are unsuccessful in the management of symptoms, oral contraceptives are recommended as the next tier of therapy. By decreasing endometrial growth, oral contraceptives limit the production of prostaglandins and leukotrienes. Indeed, lower levels of prostaglandins have been reported in the menstrual fluid of women on oral contraceptives compared with patients with dysmenorrhea who were not taking these drugs.7
Irregular menstrual cycles, an important characteristic of polycystic ovary syndrome (PCOS), are frequently encountered during the first couple years of menstruation.14 Most of these menstrual abnormalities normalize in the first 2 years after menarche, but careful follow-up and examination are necessary. In one study, half of adolescent girls between the ages of 14 and 16 with oligomenorrhea still had this menstrual problem at age 18.15 Polycystic ovary syndrome is the most common reproductive endocrine abnormality associated with irregular periods in adult women of reproductive age. Because this syndrome starts at puberty, adolescents must be monitored closely for signs of this disorder because early intervention may have a beneficial longterm effect.16 Although subtle signs and symptoms may exist during childhood, the diagnosis is typically deferred until puberty when patients present with irregular menstruation. During the peripubertal period, the hypothalamic-pituitary-ovarian (HPO) axis is relatively immature, which can lead to anovulatory cycles and make it difficult to diagnose PCOS during this time. Menarche usually occurs at a normal age in adolescents with PCOS. But data suggest that premature pubarche may be associated with development of PCOS.17–19 In a group of postpubertal adolescents with premature pubarche, 45% of the patients showed evidence of functional ovarian hyperandrogenism.17 In a study comparing 98 children with premature pubarche to Tanner stage and bone age-matched controls, mean serum insulin levels were elevated in all participants with premature pubarche for all Tanner stages. Hyperinsulinemia was noted in all participants with premature pubarche, implying that insulin resistance was present during childhood.20 Signs and Symptoms
According to the Rotterdam European Society of Human Reproduction (ESHRE)/American Society for Reproductive Medicine (ASRM)-sponsored PCOS consensus workshop, two of the following three criteria must be present in order to diagnose PCOS: irregular periods, polycystic ovaries on ultrasound, and physical or biochemical evidence of excess androgens.16 Other etiologies, such as late-onset congenital adrenal hyperplasia (CAH), hyperprolactinemia, or androgen-secreting tumors, which may lead to hyperandrogenism, must be excluded.
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Chapter 14 Reproductive Disorders in the Adolescent Patient The most common presenting complaint of adolescents with PCOS is oligomenorrhea followed by episodes of menorrhagia. The presence of oligomenorrhea at age 15 was shown to be a better predictor of oligomenorrhea at age 18 than high testosterone levels, luteinizing hormone (LH) concentration, or polycystic ovaries at ultrasound.14 Hirsutism in adolescents is most commonly caused by PCOS.21 Other skin manifestations of hyperandrogenism include acne and alopecia. Acanthosis nigricans and skin tags may be seen secondary to the accompanying hyperinsulinemia. Girls with PCOS had higher LH and androgen concentrations than controls.22 The same findings have been reported in women with PCOS. Increased LH pulsatility, elevated LH/follicle stimulating hormone (FSH) ratios, and increased ovarian volume have been described in girls with PCOS.23 During childhood, obesity is the prime cause of insulin resistance.24 However, PCOS in adolescents (and women as well) bestows a risk for hyperinsulinemia independent of weight and body composition. Euglycemic clamp studies in two groups of obese 12-year-old girls with and without PCOS showed that fasting plasma glucose levels in the PCOS group were higher than those in the non-PCOS group. Insulin sensitivity was decreased by 50% in the PCOS group compared with the non-PCOS group.25 This metabolic abnormality is a precursor to type 2 diabetes mellitus and is generally detected early in the course of PCOS. Indeed, a 33% rate of impaired glucose tolerance is noted in obese adolescents with PCOS.26 Hyperinsulinemia has also been detected in lean oligomenorrheic and hyperandrogenic adolescents.27 Thus, lean PCOS adolescents are also at increased risk of developing type 2 diabetes mellitus. Depression has been detected in one half of women with PCOS. The symptoms of hirsutism, obesity, acne, and alopecia place significant emotional stress on the adolescent during a time when she is particularly vulnerable. Because social acceptance is so important during adolescence, the girl who physically looks different from her peers is more likely to feel social anxiety.28-30 It is important to obtain a complete family history of significant endocrine problems. A family history of PCOS appears to be a significant risk factor for the development of PCOS. The rates of PCOS in premenopausal mothers and sisters of patients with PCOS are 35% and 40%, respectively.31 The patient is questioned regarding the existence of PCOS, male alopecia, female hyperandrogenism, menstrual irregularities, diabetes, obesity, and infertility on either her mother’s or father’s side of the family. Laboratory Evaluation
Endocrinologic evaluation in the adolescent is the same as that in adults and includes assessment of serum androgens as well as exclusion of other endocrine disorders associated with similar presentations such as late-onset CAH and hyperprolactinemia. Details of this investigation are discussed in detail in Chapter 15. Periodically, an oral glucose tolerance test may be necessary to assess for impaired glucose tolerance—especially in obese adolescents. Although ultrasound of the pelvis may be performed instead of a pelvic examination in the apprehensive young patient, it is not absolutely necessary. Treatment
The initial focus of treatment of PCOS is on the presenting complaint. Menstrual abnormalities are managed effectively with
hormones such as oral contraceptives and progestins. Cyclic use of progestins leads to stabilization of the endometrial lining and provides protection against endometrial cancer and hyperplasia. However, in sexually active adolescent girls, the oral contraceptive is ideal. Oral contraceptives not only regulate menses, but also decrease hirsutism and acne. By inhibiting gonadotropin secretion and increasing sex hormone-binding globulin, oral contraceptives decrease the amount of free testosterone, with a subsequent beneficial effect on the hair follicle. Contrary to what most adolescents believe, oral contraceptives do not increase body weight or fat in teenagers with PCOS.32 However, there is some concern that they may increase insulin resistance in a group already at risk for hyperinsulinemia.33 Antiandrogens such as spironolactone are quite effective in diminishing the symptoms of hirsutism and acne. A decrease in the width of the hair shaft and amount of sexual hair growth is noted at doses up to 200 mg/day. Menstrual abnormalities may occur with use of spironolactone; thus, concomitant use of oral contraceptives is commonly recommended. Hair growth changes may not be evident for 6 to 9 months. But once the rate of hair growth is decreased, she may proceed with use of cosmetic agents such as electrolysis and laser therapy. Eflornithine cream, which inhibits ornithine decarboxylase—an enzyme within the hair follicle—can slow hair growth.34 It may be applied twice a day to the affected area, but as with spironolactone, it may take several months to see any improvement in hair growth. The role of insulin-sensitizing agents in the management of PCOS in adolescents is not clear. Like adults, many PCOS adolescents have insulin resistance and are at increased risk for developing diabetes and cardiovascular disease. But the first line of therapy to normalize the abnormal metabolic profile of such patients is lifestyle modification, which includes exercise and diet. Lifestyle modification in adolescent girls is especially important because behavioral changes during puberty may have long-lasting effects. Lifestyle modification may be even more beneficial than metformin therapy in the prevention of diabetes.35 In addition, data documenting the safety of metformin use and long-term outcome in adolescents are lacking. Thus, it may be difficult to justify lifelong use of metformin in this population. There is good evidence, however, that metformin can normalize abnormal metabolic parameters both in obese and nonobese adolescents. A study of 15 obese adolescents with PCOS and impaired glucose tolerance who were given metformin 850 mg twice a day showed that the therapy decreased hepatic and peripheral insulin resistance, improved glucose tolerance, and decreased free and total testosterone levels.36 When metformin was given to nonobese adolescents, an improvement in hirsutism, free androgen index, lipid profile, and insulin parameters was again noted.37 Unfortunately, all improvements in lipid profile, hyperandrogenism, menstruation, and hyperinsulinemia are reversed within 3 months of termination of metformin.37,38
Abnormal Uterine Bleeding Abnormal uterine bleeding (AUB) is very common in girls for the first 1 to 2 years after menarche. It is defined as excessive, prolonged, or irregular bleeding in the absence of structural lesions of the uterus. In a study evaluating the menses of over 5000
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Section 2 Pediatric and Adolescent Disorders Table 14-2 Differential Diagnosis of Abnormal Uterine Bleeding Pregnancy-related disorders Disorders of blood hemostasis Chronic illness Sexually transmitted disease Endocrine disorders Medication Local gynecologic abnormalities
adolescents, the incidence of irregular menstrual cycles was 43% during the first year of menses and 20% in the sixth year.3 Thus, most adolescents eventually experience normal menses, but in the longest follow-up study on record, 5% continued to have severe episodes of anovulatory bleeding in adult life.39 Etiology
In adolescents, the most common cause of AUB is anovulation. Anovulatory cycles are usually the result of an immature HPO axis. The constant exposure of the endometrium to unopposed estrogens results in disorganized endometrial shedding. Bleeding occurs irregularly and is usually painless. The amount ranges from light spotting to levels that result in profound anemia. Because AUB is a diagnosis of exclusion, other possible causes of vaginal bleeding must be considered. The differential diagnosis of AUB is vast; a summary is given in Table 14-2. A more detailed review is given in Chapter 21. In most instances, the cause of anovulation remains unknown in adolescents. Chronic illnesses such as liver cirrhosis and renal failure may contribute to anovulation and subsequent AUB. Other circumstances that can lead to anovulation include eating disorders, weight changes, and vigorous athletics. Because it may be difficult to obtain a correct sexual history from a teenager, pregnancy complications such as a missed abortion must be considered. Although local disorders such as leiomyomas are uncommon, others such as cervicitis are more common and present as prolonged vaginal bleeding. Teenagers presenting with ovulatory AUB (menorrhagia) must be assessed for bleeding disorders. In one retrospective study, a primary coagulation defect was found in 19% of patients who were admitted to the hospital with acute menorrhagia. The prevalence of bleeding disorders rose to 50% in the subgroup of girls with menarchal menorrhagia.40 More recent studies in which the bleeding disorder was more likely to have been detected during premenarche showed a much lower rate of newly diagnosed coagulopathy.41,42 Only 3% of patients admitted for menorrhagia in these studies had a newly diagnosed coagulation disorder. On the other hand, patients hospitalized with hematologic disorders that require chemotherapy may develop severe vaginal bleeding. Evaluation
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The history should include a detailed menstrual calendar, including duration and severity of symptoms. Particular attention should be paid to past medical history, especially hematologic problems and current medication that may cause thrombocytopenia. Symptoms that may be associated with thyroid disease, excess androgen production, and prolactinomas must be sought. A sexual history should be obtained.
Certain aspects of the sexual history obtained from a young adolescent may be inaccurate. Cervical cultures for sexually transmitted disease and urine pregnancy tests should be liberally obtained. Even if a complete pelvic examination cannot be performed, an assessment of the external genitalia can provide valuable information about the amount of vaginal bleeding and evidence of androgenization. A vaginal or rectal examination should give an initial impression of the size of the uterus. The physical examination should also focus on the presence of skin changes, such as hirsutism and acanthosis nigricans. The laboratory evaluation in teens with excess vaginal bleeding initially includes a pregnancy test and complete blood count with platelets. The complete blood count can be used to evaluate the severity of the bleeding and as a guideline to determine the urgency of care. In addition, it may help rule out some major hematologic problems. If a bleeding disorder is suspected, a bleeding time, a prothrombin time, and activated partial thromboplastin time as well as a screening test for Von Willebrand disease should be ordered. Details of these are given in Chapter 21. Patients should be evaluated for potential endocrine disorders such as thyroid disease and pituitary adenomas. Treatment
In most cases, the anovulatory bleeding that girls experience is self-limited and resolves with the maturation of the HPO axis. Therefore, the goal of treatment is support and prevention of anemia. Patients with known medical conditions that may contribute to anovulation and those with bleeding disorders that were identified premenarche should be treated aggressively to prevent the problem from occurring. It is important to discuss the patient’s chronic hematologic disorder with her hematologist so that a plan can be implemented that will prevent or reduce the severity of the AUB. Treatment of AUB is based on the severity and duration of vaginal bleeding. If the hemoglobin and hematocrit are within normal range and the adolescent’s periods are slightly prolonged or cycles are slightly shortened, she can be reassured and seen every 3 months. During this time, she should be instructed to keep a menstrual diary, which can be reviewed at each visit and used to teach the adolescent about her menses. Eventually, most of these teens will begin to experience normal menses. Patients in whom the bleeding occurs frequently (every 2 to 3 weeks) and the blood counts are normal or slightly below normal will benefit from cyclic addition of medroxyprogesterone acetate (10 mg for 10 to 14 days). Patients with prolonged amenorrhea or oligomenorrhea followed by episodes of abnormally heavy bleeding may be given medroxyprogesterone acetate every 2 to 3 months to initiate bleeding and preempt abnormal endometrial shedding. Iron supplementation should be initiated. There are data to support the use of NSAIDs to decrease the amount of blood loss.43,44 This is especially the case in patients with ovulatory AUB (menorrhagia). Patients presenting with mild anemia frequently experience moderate to heavy menses every 2 to 3 weeks. In such cases, oral contraceptives or progesterone may be used to control the bleeding. Use of medroxyprogesterone acetate or norethindrone acetate for 10 to 14 days can help stabilize the endometrium followed by global shedding and controlled period. These agents may not be successful in cases where the bleeding has been heavy and prolonged. In such cases, the endometrium usually is very thin and some amount of
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Chapter 14 Reproductive Disorders in the Adolescent Patient estrogen is necessary to heal the lining. Thus, monophasic combined oral contraceptives may be more effective. Although 10 to 14 days of cyclic progestin therapy is adequate for anovulatory AUB, luteal phase progestin therapy is less effective for ovulatory AUB. Progestin therapy for 21 days of the cycle (day 5 to day 26, for example) is more effective. If the bleeding is heavy but not emergent, an oral contraceptive pill may be taken every 8 to 12 hours until the bleeding has stopped. The dose can then be tapered down slowly to one pill a day. Patients are instructed to call back daily with updates on their bleeding and any complaints. After 3 weeks of not bleeding, the oral contraceptive is withdrawn and the patient should be told to expect a period. It is typically recommended that she cycle on oral contraceptives for a couple of months before re-evaluation. Treatment of Severe Anemia
In some cases, the degree of anemia and amount of bleeding require administration of an oral contraceptive pill every 4 to 6 hours. Within 24 to 36 hours, a significant decrease in the amount of bleeding should be noted, at which point the dose can be tapered back. Because these patients will experience significant nausea, an antiemetic must be prescribed to keep them comfortable enough to adhere to the treatment regimen. Another option is use of oral high-dose estrogen such as conjugated estrogens (Premarin) or micronized estradiol (Estrace) every 4 to 6 hours. Once bleeding has stopped, the dose can be tapered and progesterone added to the regimen. Adolescents whose initial hemoglobin level is less than 7 g/dL and are bleeding actively and heavily may need to be admitted for blood transfusion. A coagulation panel must be assessed prior to any blood transfusion or hormonal manipulation. If deemed clinically stable, she may be initiated on oral contraceptives. However, if she is severely hemorrhaging or unable to take medications orally, she can be given intravenous conjugated estrogens (Premarin) 25 mg every 4 hours for 24 hours or less if she stops bleeding.45 Once the bleeding has decreased or stopped, the patient should be given a combination oral contraceptive or progesterone. In instances where high-dose estrogen therapy is contraindicated, high doses of progesterone such as norethindrone and medroxyprogesterone acetate may be used. Gonadotropinreleasing hormone agonists have also been used to manage AUB in patients who are unresponsive to hormonal management or have contraindications to their use. Antifibrinolytic agents have been used successfully to manage menorrhagia. However, there is minimal data on their use for this indication in adolescents. In one comparative study in adults, mefenamic acid decreased blood loss by 20% and tranexamic acid reduced blood loss by 54%.46 Its use in adolescents has been reserved for patients with organic pathology in whom hormonal therapy has failed. Dilatation and curettage and hysteroscopy are indicated only when the patient is unresponsive to medical therapy—they are the last line of evaluation and therapy for teenagers. A report of successful endometrial ablation on a teen with severe uterine bleeding complicated by end-stage renal disease exemplifies the critical nature of some patients.47 However, this procedure is only considered an alternative to hysterectomy. Other medical treatments that are used in adults have been sporadically used in adolescent girls (see Chapter 21).
Long Term Outcome
Continued follow-up is mandatory in adolescents experiencing AUB, as illustrated by the results of a 25-year follow-up study.39 This study was performed before hormonal therapy was an option. However, it is quite revealing that the change to normal menses was greatest in the first 2 years of the study. By 4 years, 50% still had AUB. No patient developed normal periods after 10 years of persistent abnormal bleeding. More than half of these patients presented with infertility. Hence, follow-up provides an opportunity to either reassure the adolescent as she normalizes or to educate her about the need for continued medical therapy and potential options for the future.
AMENORRHEA Primary amenorrhea is defined as the absence of any menstrual flow by age 15 if the patient has developed secondary sexual characteristics or within 5 years of breast development. Secondary amenorrhea is defined as the absence of menstruation for 6 months in an adolescent who has previously established menstruation or the absence of menstruation for a minimum of 3 previous cycle intervals. Although these terms provide information regarding the menstrual cycle, they do not help exclude various diagnoses. Amenorrhea is discussed in detail in Chapter 16. However, an overview is given here to address the differential diagnosis in an adolescent girl who has gone through puberty normally but presents without a period. These patients typically enter the healthcare system through a gynecologist. Patients may have amenorrhea associated with a pubertal disorder. This topic is covered in a separate chapter (see Chapter 11).
Amenorrhea without Pubertal Delay The differential diagnosis of the adolescent presenting with normal secondary sexual characteristics and amenorrhea is vast (Table 14-3). Hence, only the most common ones are discussed here. Pregnancy must be excluded first. The adolescent is
Table 14-3 Differential Diagnosis of Amenorrhea without Pubertal Delay Congenital anomalies of the genital tract
Imperforate hymen Transverse septum Cervical agenesis Vaginal agenesis Müllerian agenesis
Receptor anomalies
Androgen insensitivity syndrome
Enzyme defects
21-hydroxylase deficiency 11-hydroxylase deficiency
Specific gonadal disorders
Iatrogenic/chemotherapy/radiation Premature ovarian failure Gonadal dysgenesis Polycystic ovary syndrome
Hypothalamic/pituitary disorders
Chronic illness Pituitary adenoma Craniopharyngioma Eating disorder Athlete Psychiatric illness Obesity Drugs
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Section 2 Pediatric and Adolescent Disorders with imperforate hymen, but abnormalities such as a bifid clitoris, ectopic ureter, polydactyly, hypoplastic kidney, and imperforate anus have been reported. The reproductive tract must be further assessed via imaging techniques. A large hematocolpos is usually easy to identify. The clinical presentation, examination, and imaging studies must all support the diagnosis. The following case illustrates the importance of this concept. SB is a 15-year old female who presented with complaint of cyclical abdominal pain and amenorrhea to her gynecologist. She had been experiencing pelvic and abdominal pain for 2 years. She runs track, and the delay in her menstruation had been attributed to her running. Upon examination of the external genitalia, no hymeneal opening could be appreciated. No pelvic masses could be appreciated via rectal examination. Imaging of her pelvis revealed only mild hematometra. The patient was subsequently scheduled for a hymenectomy.
Amenorrhea and cyclical pelvic/abdominal pain occurs with imperforate hymen, but the lack of a hematocolpos on the imaging studies should lead the physician to another diagnosis. The differential diagnosis should include vaginal agenesis, cervical agenesis, or high transverse septum. Treatment Figure 14-2 In this photograph, a bulging bluish membrane is easily seen that represents an imperforate hymen.
questioned and assessed for signs of hirsutism, galactorrhea, weight changes, dietary changes, changes in exercise patterns, chronic illness, visual changes, and headaches. Despite the young age of the patient, the external genitalia must be evaluated. This entails at least a visual inspection of the external genitalia and possibly a rectal examination to assess for any pelvic masses. A young adolescent should never be forced into a speculum examination. If imaging studies are inconclusive, an examination under anesthesia may be necessary. Imperforate Hymen
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This anomaly results from incomplete canalization of the hymen (Fig. 14-2). It is most commonly detected during adolescence. It may be diagnosed in utero or during the neonatal period.48 The incidence of this anomaly is approximately 0.1% of term infant girls, and it is believed to occur sporadically. However, there have been rare reports of familial occurrence of imperforate hymen.49,50 Although a common mode of inheritance has not been identified, it seems prudent to obtain a family history of reproductive tract defects. When detected during infancy, the imperforate hymen presents as a mucocele. It is typically asymptomatic and evident on inspection of the external genitalia. In some instances, the hydrocolpos is large enough to cause urinary tract obstruction and urine retention. In such cases, surgical decompression of the hydrocolpos is necessary. Urinary tract infections have been reported in patients with mucoceles and may potentially lead to formation of a pyocolpos.51 The perimenarchal adolescent typically presents with a complaint of cyclic abdominal pain. It may take several months before the cyclic nature of the pain becomes evident to the adolescent and her family. Evaluation of the external genitalia usually reveals a thin bulging hymen, which may have a bluish hue secondary to the obstructed blood. Associated anomalies are rare
When the diagnosis is clear, a cruciate incision is made and the hymen is removed. Due to risk of incomplete removal of tissue, reformation of hymenal adhesions, and possible pyocolpos, the imperforate hymen should only be removed in the sterile conditions of the operating room. Unlike other vaginal anomalies, placement of a vaginal mold is not required after this repair. Long-term studies are few. Fifteen patients with imperforate hymen were evaluated over a period of 14 years.52 Although half of the patients expressed concern about their future fertility, the 11 patients who had become sexually active at the time of the questionnaire denied any sexual dysfunction. On examination, all 15 patients had normal external genitalia and no difficulty with micturition or defecation. In a similar study, Rock53 assessed the reproductive outcome of 22 women who underwent repair of their imperforate hymen. Of the 15 women who attempted pregnancy, 86% conceived. Androgen Insensitivity Syndrome
Complete androgen insensitivity syndrome is the third most common cause of primary amenorrhea after gonadal dysgenesis and müllerian agenesis. The incidence of androgen insensitivity syndrome is between 1/40,000 and 1/99,000; it was first reported in the literature by Morris in 1953.54,55 Such adolescents have a 46,XY karyotype. In 85% to 90% of cases of androgen insensitivity syndrome, a mutation may be found in the androgen receptor gene.56 This mutation is located on the X chromosome at Xq11-1257 and leads to a continuum of virilization disorders ranging from mild androgen insensitivity syndrome to the complete form. Over 300 mutations in the X-linked androgen receptor gene have been identified.58 The inability to recognize androgens leads to development of female external genitalia in these patients. However, due to the existence of the testes and production of müllerian inhibiting substance (MIS), the müllerian system usually regresses.59,60 These patients have normal-appearing female external genitalia associated with a blind-ending vaginal pouch. Although most patients are diagnosed after puberty and on occasion at birth or during infancy, this diagnosis is encountered when a baby girl with no evidence
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Chapter 14 Reproductive Disorders in the Adolescent Patient of sexual ambiguity presents with unilateral or bilateral inguinal hernias. On examination, such patients are noted to be of normal or slightly above average height. They have undergone breast development, but on close inspection the breasts have an abnormal appearance. The nipples are typically smaller and the areolae are pale. They may have scant or no axillary and pubic hair. The labia minora of the external genitalia may be underdeveloped. Laboratory evaluation reveals normal male range serum testosterone levels and slightly elevated LH levels. Imaging of the pelvis fails to show a uterus. It is important to determine the location of the testes. They may be intra-abdominal or within the inguinal canal. Although tubular development is noted within the testes, there is no evidence of spermatogenesis. Because these patients are at an increased risk for gonadal neoplasia, gonadectomy is indicated. The timing of gonadectomy is unclear. Some clinicians advocate removal of the gonads after the patient has completed puberty if the diagnosis is made before or during puberty. Adolescents appear to undergo smoother pubertal changes with their own hormones versus exogenous hormone therapy. The probability that the short delay will result in neoplastic gonads is probably small. Other clinicians have advocated removal of the gonads upon diagnosis to prevent any potential androgenization that may occur with puberty. If gonadectomy is performed after puberty, the patient and her family must be advised of the need for estrogen therapy to help maintain breast development and bone health. Differential Diagnosis
Patients with androgen insensitivity syndrome must be differentiated from patients with Mayer-Rokitansky-Küster-Hauser syndrome. Both types of patients will have breast development and primary amenorrhea. However, the latter has a 46,XX karyotype and ovaries. Because the testosterone level of patients with androgen insensitivity syndrome is in the male range, measuring the testosterone level can help distinguish these
two entities. After documenting an elevated testosterone level, the clinician should perform a karyotype to confirm the diagnosis. Treatment
Such patients typically have a blind-ending vaginal pouch. Thus, vaginal lengthening may be necessary through serial dilatation of the pouch. Surgery is typically not indicated. In one long-term study performed at Johns Hopkins University, 14 women with complete androgen insensitivity syndrome were followed for decades.62 Their ages ranged from mid-20s to mid-60s. More than half of these women did not require lengthening of the vagina. All the women were satisfied with their female gender, 71% reported satisfaction with their sexual function, and 77% experienced orgasm. More than half of the women exhibited a limited amount of knowledge about androgen insensitivity syndrome. But only half of them were dissatisfied with this limited knowledge. This study stresses the importance of continued counseling and support for adolescents as they progress into adulthood.
EATING DISORDERS Eating disorders are complex disorders with social, cultural, psychological, physiologic, and behavioral components. These patients usually present to the gynecologist with a menstrual disorder such as amenorrhea. Due to the irregularities in their menses, adolescents with eating disorders may initially present to a gynecologist. Hence, an understanding of the prevalence of this entity and modes of diagnosis, treatment, and long-term concerns must be obtained. The incidence of eating disorders peaks during the early teens around the time of menarche and also in the late teens when the adolescent is about to leave home for college or a new job. Eating disorders can be categorized into anorexia nervosa, bulimia nervosa, and eating disorder not otherwise specified (Table 14-4). Adolescents with anorexia nervosa have a fear of becoming fat and
Table 14-4 Diagnostic Criteria for Eating Disorders Anorexia nervosa 1. Intense fear of becoming fat or gaining weight, even though underweight 2. Refusal to maintain body weight at or above a minimally normal weight for age and height 3. Disturbed body image, undue influence of shape or weight on self-evaluation, or denial of the seriousness of the current low body weight 4. Amenorrhea or absence of at least three consecutive menstrual cycles (persons with periods only inducible after estrogen therapy are considered amenorrheic) Bulimia nervosa 1. Recurrent episodes of binge eating, characterized by a. Eating a substantially larger amount of food in a discrete period of time (i.e., in 2 hours) than would be eaten by most people in similar circumstances during that same time period b. A sense of lack of control over eating during the binge 2. Recurrent inappropriate compensatory behavior in an attempt to prevent weight gain, such as self-induced vomiting, use of laxatives, diuretics, fasting, or hyperexercising 3. Binges or inappropriate compensatory behaviors occurring, on average, at least twice weekly for at least 3 months 4. Self-evaluation unduly influenced by body shape or weight 5. Disturbance not occurring exclusively during episodes of anorexia nervosa Other 1. 2. 3. 4.
eating disorders (persons who do not meet criteria for anorexia nervosa or bulimia nervosa) All criteria for anorexia nervosa except has regular menses All criteria for anorexia nervosa except weight still in normal range All criteria for bulimia nervosa except binges < twice a week or for < 3 months A patient with normal body weight who regularly engages in inappropriate compensatory behavior after eating small amounts of food (ie, self-induced vomiting after eating two cookies) 5. A patient who repeatedly chews and spits out large amounts of food without swallowing 6. Binge eating disorder—recurrent binges but does not engage in the inappropriate compensatory behaviors of bulimia nervosa
Adapted from American Psychiatric Association: Diagnostic and Statistical Manual of Mental Disorders, 4th ed., Washington, D.C., American Psychiatric Association, 1994, pp. 539-550.
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Section 2 Pediatric and Adolescent Disorders a distorted body image and have experienced extreme weight loss or lack of weight gain. Anorexia nervosa affects 1% of adolescents, the majority of whom are females.63 Patients with bulimia may have normal weight or be overweight. They consume or “binge” large amounts of food at least twice a week for a period of at least 3 months. This is typically followed by purging via self-induced vomiting, use of laxatives, or hyperexercising. It is estimated that 1% to 5% of high school females and as many as 19% of college girls have bulimia.64 The incidence of eating disorder is dependent on tests used to assess the problem. When the modified eating attitudes test was administered, the rate of eating disorder among girls who came to the hospital or endocrinology clinic was 17% compared with a rate of 7% in those presenting for health maintenance visits in the same institution.65 Female athletes are particularly vulnerable to eating disorders. Unhealthy eating behavior has been reported in up to 62% of college gymnasts.66 Many employ unhealthy behaviors to control their weight, including the use of diet pills, diuretics and laxatives, binging, and self-induced vomiting. The female athletic triad is the combination of amenorrhea, eating disorder, and osteopenia. To improve her athletic performance, the patient attempts to lose weight. However, with time, the desire to lose weight eventually becomes the primary goal even at the expense of her athletic performance.
Signs and Symptoms The signs and symptoms of anorexia nervosa and bulimia are noted in Tables 14-5 and 14-6. Menstrual abnormalities such as amenorrhea and oligomenorrhea are the usual presenting symptoms to the gynecologist. A common symptom in such patients is constipation, which may be accompanied by abdominal pain. The methods by which patients attempt to control their weight may contribute to their symptoms. Thus, cardiac arrhythmias and electrolyte abnormalities are noted in patients who lose weight very quickly via severe purging and binging and use of laxatives and diuretics. Chronic problems of binge eating and purging include enlargement of the parotid gland, mouth sores, eroded dental enamel, and osteoporosis.
Evaluation
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The evaluation of a patient with an eating disorder is described in Table 14-7. An attempt is made to determine maximum and minimum weight and the patient’s ideal body weight. Screening questions such as stress associated with sports, family, and school must be asked. To determine eating attitudes, a screening test for eating disorder should be performed. Concern by family members or peers about an eating disorder should raise a red flag. Other behaviors that may be suspicious are isolation from friends, recent changes in dietary habits, change in bowel habits, and frequent trips to the bathroom after meals. The physical examination should focus on measuring the patient’s height and weight, orthostatic blood pressure, and pulse. The endocrine abnormalities noted in patients with anorexia nervosa include low estradiol and gonadotropin levels, high cortisol levels, and normal prolactin levels.67 Although thyroid-stimulating hormone (TSH) and free thyroxine (T4) levels are normal, the reverse T3 is high and T3 levels are low. In adolescents with anorexia nervosa, LH regresses to prepubertal levels at the nadir
of the weight loss.68 Finally, the leptin level is low in patients with anorexia nervosa and is predictive of amenorrhea in underweight women. Although these hormonal abnormalities normalize with weight gain, some patients still remain amenorrheic. Table 14-5 Symptoms and Signs of Anorexia Nervosa Symptoms General well-being Weakness Fatigue, low energy (despite high physical activity) Fainting Cold intolerance Menstrual history Primary or secondary amenorrhea Gastrointestinal symptoms Constipation Bloating Early satiety (from delayed gastric emptying and slowed metabolism) Integument Dry skin Blue hands and feet Scalp hair loss Signs Vital signs and biometrics Hypothermia, bradycardia, orthostatic hypotension Short stature (with earlier onset of eating disorders) Delayed puberty Lanugo hair Hypoestrogenic signs (ex. vagina) Cardiac murmurs
Table 14-6 Symptoms and Signs of Bulimia Nervosa Symptoms Menstrual disorder Oligomenorrhea Amenorrhea Irregular periods Nonspecific symptoms Heartburn Chest pain Muscle cramps Weakness Fainting Signs Vital signs Orthostatic hypotension Oral cavity Swollen parotid gland Mouth sores Dental caries Bloody diarrhea Easy bruising
Table 14-7 Evaluation of Patient with an Eating Disorder Document eating attitudes Menstrual disorder Check urine pregnancy test Rule out other endocrine disorders Hypoestrogenemia Verify with serum estradiol Amenorrhea Check bone density if more than 6 months If associated with delayed puberty check bone age Blood tests Serum electrolytes Complete blood count and erythrocyte sedimentation rate
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Chapter 14 Reproductive Disorders in the Adolescent Patient Complications
Incidence
A well-known complication of anorexia nervosa is bone loss.69 Adolescence is a critical period for bone accretion because over half of the entire bone mass is achieved during the teen years. In a study of 50 adolescents with anorexia, 90% had reduction in bone mass if they had amenorrhea lasting for more than 6 months. Those who developed anorexia before menarche had lower bone mass than those who developed the disease after menarche. In addition, the premenarchal girls with anorexia were followed for 3 years, and no increase in bone mass was noted, which suggests that the insult was potentially permanent.70
Ovarian torsion causes venous congestion, intraovarian hemorrhage, and eventual tissue necrosis. It is encountered in 3% of all emergent gynecologic surgery.80 The true incidence of ovarian torsion is unknown in children and adolescents. However, when the pathology of 140 girls younger than age 21 (median age, 15) presenting with a pelvic mass was reviewed in one institution in Louisville, Ky., 17.8% of the patients had ovarian torsion.81 A review of a children’s hospital 15-year experience with surgical management of ovarian masses in 102 young children (mean age, 9.8 ± 5.5 years) showed that nearly one third of their patients had ovarian torsion.82
Management Detection at a younger age, shorter duration of illness, and less weight loss are associated with a better prognosis. On the other hand, patients with extreme weight loss, depression, and eating disorder associated with vomiting have a worse prognosis. The best approach to promote recovery is early identification and treatment via a multidisciplinary team. This team usually consists of a physician, dietician, and therapist. Psychiatric consultation is necessary to rule out comorbid diagnoses such as depression, anxiety disorder, or obsessive-compulsive disorder. Adequate coping skills must be developed to potentially help prevent relapse, which is not uncommon in these disorders. Criteria for hospitalization have been established; the main goals are medical stabilization and weight maintenance. Weight restoration is essential to allow spontaneous resumption of menses.71 Increase in body weight and resumption of menses are usually associated with increase in bone mineral density.72,73 However, it is not clear whether this bone loss is completely reversible.74 The role of estrogen therapy in the treatment of osteopenia in adolescents with eating disorders is unclear and has less benefit if there is little weight gain.75 In a randomized clinical trial of 48 women, no significant change was noted in the bone mineral density of the group that received estrogen compared with the control group. However, a subset of the estrogen group with an initial body weight that was 70% less than their ideal weight had a 4% increase in mean bone mineral density, whereas the controls of comparable low initial body weight had a 20% decrease in bone mineral density. This study suggested that estrogen therapy might benefit a subset of very low-weight women with anorexia nervosa.76 Although full recovery in regards to weight, development, menstruation, and normal eating behavior occurs in 50% to 70% of treated adolescents,77,78 physical and mental disorders are noted into adulthood.79 These include anxiety disorders, cardiovascular symptoms, chronic pain, and chronic fatigue and depressive disorders. These findings suggest that not only is increased recognition and identification of eating disorders in adolescents of utmost importance, but also once detected, patients should be directed toward specialized treatment programs.
OVARIAN TORSION A relatively common disorder that has major implications for reproductive health in an adolescent population, ovarian torsion was often managed by nongynecologists in the past, sometimes with poor results (e.g., loss of a gonad).
Etiology There are two main risk factors for ovarian torsion: prior existence of an ovarian mass or cyst and prior pelvic surgeries. The most common pathologies are ovarian cysts, benign teratomas, and serous cystadenomas.83 Normal ovaries have also been noted, and torsion in such instances may be secondary to increased mobility of the adnexa secondary to an elongated utero-ovarian ligament or long fallopian tube and mesosalpinx.84,85 Malignant lesions are not a common cause of ovarian torsion in the adolescent population.81,82
Signs and Symptoms Typical presenting complaints may include sudden onset, sharp and stabbing pain, or colicky pelvic/abdominal pain radiating to flank, back, or groin. The pain is usually associated with nausea and vomiting that waxes and wanes.83 Peritoneal signs of rebound and guarding are very late signs and thus are rare at presentation. The patient may or may not have fever and leukocytosis depending on the timing of presentation. Pelvic examination may reveal just mild adnexal tenderness or severe pain. In most cases, the patient has ovarian enlargement, although in some cases the ovaries are of normal size. The differential diagnosis is extensive and includes ovarian cysts, ectopic pregnancy, appendicitis, pelvic inflammatory disease, diverticulitis, and renal colic. A high index of suspicion remains the most valuable tool for making this diagnosis. Patients with ovarian torsion have a delayed diagnosis as a result of failure to consider the possibility of ovarian torsion at presentation. In a review of 87 cases of confirmed ovarian torsion in two hospitals, ovarian torsion was considered in the differential diagnosis in only 47% of the cases.83
Imaging Ultrasound of the pelvis is the primary imaging modality used to evaluate patients with suspected ovarian torsion, but magnetic resonance imaging (MRI) may also be useful (Figs. 14-3 and 14-4). The ovarian ultrasound image may be very nonspecific and must be differentiated from an ovarian cyst or an ovarian mass. The sonographic features of a twisted ovary include a complex, solid or cystic central ovarian mass associated with multiple peripheral small cysts.86 This appearance reflects congestion of the ovary and is considered to be moderately sensitive but highly specific for torsion.87 The presence of these findings (ovarian mass and peripheral small cysts) in a study of 41 girls ages 3 to 13 was
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Figure 14-5 Laparoscopic view of twisted adnexa. Simple detorsion with removal of the ovarian cyst is all that was necessary. Figure 14-3 A transabdominal ultrasound, tranverse view, showing an ovary with minimal vascular flow, suggestive of torsion of the ovary.
ovaries.89 There are conflicting data as to the utility of this modality. Normal Doppler flow to the ovaries does not exclude torsion, and Doppler flow was noted to be present in 60% of surgically confirmed twisted ovaries.90,91 Intermittent torsion or incomplete vascular occlusion may account for the continued flow to the ovary. Technical difficulties may also lead to false-negative results.92 In adolescents in whom trans-abdominal ultrasonography may be the more common means of assessing the ovary, it is likely that the twisted vascular pedicle may not even be appreciated. Doppler ultrasound may potentially be useful in predicting the viability of the ovarian tissue. A report that showed both arterial and venous flow in 16 of 28 surgically confirmed twisted ovaries also demonstrated that 15 of these ovaries were viable.90 Thus, in conjunction with the findings at the time of surgery, Doppler flow to the ovaries may be able to assist with the decision to proceed with conservative surgery versus oophorectomy.
Management
Figure 14-4 Magnetic resonance image of the pelvis showing an edematous ovary suggestive of torsion.
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associated with a sensitivity of 64% but a specificity of 97%.88 However, these findings are not always observed because the appearance of the ovary may be related to the duration and degree of the torsion. Intermittent torsion may cause venous or lymphatic obstruction alone, leading to massive ovarian edema. Ovarian edema may be associated with ascites. The triad of hydrothorax, ascites, and a benign solid tumor such as a fibroma is referred to as Meig’s syndrome. Color Doppler ultrasound to detect the absence of blood flow to the ovary is another modality commonly used to assess ovarian torsion. Lack of flow to the ovary should indicate torsion. On the other hand, absence of internal ovarian flow may be nonspecific and may be found in cystic ovarian lesions as well as in twisted
Once the diagnosis of ovarian torsion is made, the time to surgery should be minimized to maximize ovarian viability (Fig. 14-5). However, in one review, only 26 of 87 patients had surgery within 24 hours of presentation. The mean time from presentation to surgery was 5.8 days.83 The goal of surgery is “detorsion” and possible salvage of the ovary.93,94 After the ovary is untwisted, it is assessed for signs of reperfusion. In a review of 58 women who had laparoscopic detorsion of their ovaries, 54 of the 58 (93%) ovaries showed sonographic evidence of ovarian function by 3 months postsurgery.95 Thus, although ovaries were noted to be necrotic or ischemic at the time of surgery, ovarian function is conserved. After detorsion of the blue/black ovary and establishment of reperfusion, the ovary should be assessed for signs of viability. Mild postoperative febrile morbidity may be noted. It may take several months for the size of the ovary to decrease to normal.96 During surgery, an attempt should be made to find the cyst or mass that may have caused the torsion. However, edematous, friable ovarian tissue may make it difficult to find the mass. All cases of detorsion should be followed up with ultrasound imaging of the ovaries. Given the low malignancy potential in adolescents,
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Chapter 14 Reproductive Disorders in the Adolescent Patient a persistent mass may warrant follow-up laparoscopy for cystectomy. Ovariopexy
The role of ovariopexy is not clearly defined by the literature.97,98 Ovariopexy seems to be indicated in cases of repeat or bilateral ovarian torsion, prior loss of adnexa, or abnormally elongated utero-ovarian ligament. This decision has typically been left to the surgeon’s discretion. It would seem likely that ovariopexy could reduce the risk of future ovarian torsion, but there are no data to support this supposition. Several methods of ovariopexy have been described. They include fixation to the pelvic sidewall or attachment to the round ligament or the posterior aspect of the uterus. Shortening of the utero-ovarian ligament by placing a running stitch through the elongated utero-ovarian ligament may maintain the ovary in the most anatomically correct position.99
Table 14-8 Etiology of Recurrent Abdominal Pain Gynecologic causes
Dysmenorrhea Mittlesmertz Endometriosis Pelvic inflammatory disease Ovarian cysts, rupture, torsion, hemorrhage Obstructing müllerian anomalies
Nongynecologic causes
Constipation Lactose intolerance Irritable bowel syndrome Interstitial cystitis Abdominal wall trigger points Inflammatory bowel disease Pancreatitis Ureteral calculus
Psychogenic
Sexual abuse Physical abuse Depression Eating disorders Drug use
Recurrence Although subsequent asynchronous ovarian torsion is rare, an active attempt should be made to educate the adolescent about her pathology. With this knowledge, she may seek care earlier during a recurring episode and thereby increase possibility of ovarian salvage. In a patient with a known history of ovarian torsion, it seems reasonable to prevent any cyst formation—which may be an impetus to torsion—by suppressing cyst formation with the use of oral contraceptives.
CHRONIC PAIN DISORDERS Recurrent abdominal pain or chronic pelvic pain in the adolescent population is a problem that frustrates both the physician and the adolescent and her family. The diagnosis of chronic pelvic pain is made if the following criteria are met: 1. The patient has pain in the lower abdomen of at least 3 months’ duration. 2. The pain has disrupted the adolescent’s normal activities and is not relieved by non-narcotic analgesics. 3. Multiple visits have been made to the emergency department or to the physician’s office and no definitive diagnosis has been made. The incidence of recurrent abdominal pain in children and adolescents is estimated at 10% of school-age children.100 In one study, organic causes were identified in 1 of 20 patients.101 In recent years, an increasing number of teenagers have had chronic pelvic pain from a variety of organic causes.102 The etiology of recurrent abdominal pain can be secondary to gynecologic or nongynecologic causes. The rare and the not-sorare causes are discussed in Table 14-8. Rare causes of abdominal pain include appendiceal colic, Henoch-Schönlein-purpura, and chronic pancreatitis. Before 1980, many adolescents with chronic pelvic pain underwent laparotomy.103 However, the modern multidisciplinary approach used in the investigation and management of chronic pelvic pain rarely resorts to laparotomy. The team should consist of representatives from gynecology, gastroenterology, urology, physical therapy, psychology, and/or psychiatry for assessment and treatment.
Endometriosis in the Adolescent Multiple studies have confirmed the existence of endometriosis in adolescents. The incidence ranges from 38% to 73%.104–106 Although rare cases of premenarchal endometriosis have been described, the mean age of presentation is 15.9 years. Adolescents can present with both cyclic and acyclic pain. Other presenting symptoms are dysmenorrhea, irregular periods, dyspareunia, abdominal pain, nausea, constipation, and diarrhea. The physical examination usually fails to reveal an underlying pathology. In most series, pelvic tenderness is noted on examination. Diffuse or localized pelvic tenderness is noted in most patients. The likelihood of finding and palpating an endometrioma is small in adolescents. Few patients will have an adnexal mass.107 Hence, neither the physical examination nor the history is very helpful in identifying this diagnosis. The history and physical examination are performed to primarily rule out other causes of chronic pelvic and abdominal pain. Evaluation of pelvic pain includes pelvic imaging. Ultrasonography and magnetic resonance imaging can reveal obstructed müllerian anomalies or adnexal or uterine masses. However, they are typically not helpful in diagnosing nonovarian endometriosis. Thus, the primary means of detecting endometriosis in the adolescent is laparoscopy. Once the patient has failed to respond to NSAIDs and oral contraceptives, laparoscopy for assessment of the pelvis may be indicated. Low-stage disease is found in the majority of cases. But as in adults, the stage of disease is not a good indicator of the degree of pain experienced. The distribution of severity of disease is typically weighted to the early stages. In one study, stage I endometriosis was seen in 80% of patients and stage II in 12% of patients.106 Stage III and stage IV disease was seen in only 6% and 2% of their subjects, respectively, and these patients were more likely to have obstructive müllerian anomalies. Relief of the obstruction leads to regression of these endometriotic lesions and pain.108 Hence, extensive ablation and excision of these lesions may not be indicated in this subgroup of patients. The laparoscopist must be aware of the unique aspects of endometriosis in the adolescent. The lesions noted in the adolescent are atypical and may appear as clear papules, red lesions, flamelike lesions, white lesions, and glandular lesions. Clearly,
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Section 2 Pediatric and Adolescent Disorders the appearance of endometriosis changes as the woman ages. To help identify clear lesions, Laufer described the technique of filling the pelvis with fluid and assessing the pelvic sidewalls laparoscopically “under water.”109 Subtle endometriotic lesions have been reported in 40% to 55% of patients.110,111 Hence, a biopsy of atypical lesions may be warranted to help confirm the diagnosis. The goal of therapy in such patients is control of pain and preservation of fertility. Due to the long-term nature of the disease, medical therapy is the mainstay of treatment. Surgical therapy is used primarily for diagnosis and occasionally for extirpation of disease. The response to removal of disease via excision or ablation of lesions in stage I patients (seen primarily in adolescents) has been reported to be relatively poor.112 As in adults, agents used for pain control in adolescents include oral contraceptives, NSAIDs, progestational agents, and GnRH agonists. Although danazol improves pain, its androgenic side effects are intolerable to the adolescent considering long-term therapy.113 Concomitant symptoms, such as constipation and irritable bowel syndrome, should be treated aggressively and the adolescent seen every 3 to 6 months. This type of follow-up will be reassuring to the patient and her family. Questions regarding the long-term nature of the disease and fertility issues should be addressed. Free and open discussion will also provide the opportunity to educate and empower the patient and help her avoid the need for repetitive surgery.
Chronic Constipation This is marked by a history of infrequent bowel movements or straining with bowel movements. A careful physical examination, including a rectal examination, may also point to the diagnosis. Irregular bowel movements may also accompany other disorders such as endometriosis. A double-blind, randomized study showed that the use of empirical fiber decreased the frequency of recurrent abdominal pain, possibly due to alterations in colonic transit time.116
Irritable Bowel Syndrome Irritable bowel syndrome (IBS) may also be a cause of recurrent abdominal pain. It affects 14% of high school students and 6% of students in earlier years.117 Symptoms include alternating constipation and diarrhea, abdominal pain, frequent bowel movements, straining, bloating, and a sense of incomplete evacuation. Children who suffer from depression, headaches, and anxiety seem more prone to IBS.118 A recent study measured rectal sensation and rectal contractile response to a meal in eight children with IBS and concluded that they had a significantly lower threshold response for pain and a disturbed contractile response to a meal.119 They further concluded that sensory and motor abnormalities may play a pathologic role in childhood IBS. Dietary therapy includes adding extra fiber and may provide symptomatic relief.
Pelvic Inflammatory Disease A high index of suspicion must be maintained for pelvic inflammatory disease (PID) in the adolescent population. Most clinicians will use laparoscopy to definitively diagnose PID in adolescents if they have recurrent symptoms and cultures are negative.114 In addition, laparoscopy is indicated if symptoms of pelvic pain persist despite treatment of culture-proven PID. An empathic approach must be maintained in both relieving pain and dealing honestly with the patient’s questions regarding future fertility.
Müllerian Anomalies Müllerian anomalies are more commonly the cause of pelvic pain and dysmenorrhea in adolescents than adults. Hence, it is mandatory to confirm normal müllerian anatomy either via pelvic examination or imaging in the adolescent presenting with pain to the gynecologist. These anomalies are discussed in detail in Chapters 12 and 51.
Lactose Malabsorption
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A nongynecologic cause of chronic abdominal pain is lactose malabsorption. At least one study identified lactose malabsorption in 24% of patients ages 6 to 18 with recurring abdominal pain.115 Presenting symptoms are increased flatus, diarrhea, bloating, and abdominal pain. An inquiry regarding gastrointestinal symptoms should be routine during the history and physical examination of an adolescent presenting with pelvic/abdominal pain. If the level of suspicion is high for gastrointestinal causes, an evaluation should be requested from a pediatric gastroenterologist. Lactose malabsorption can usually be identified by an abnormal breath hydrogen test.
Inflammatory Bowel Disease One quarter of cases of inflammatory bowel disease (IBD) are diagnosed during childhood or adolescence.120 Many patients with IBD have a genetic predisposition. A relatively small percentage of patients with Crohn’s disease present with isolated abdominal pain.121 Concomitant symptoms can include weight loss, anorexia, diarrhea, and fever. An increased sedimentation rate and abnormal complete blood count may suggest the presence of Crohn’s disease. All patients with recurrent abdominal pain should be checked for occult blood via rectal examination, and both the perianal and vulvar area must be examined carefully. Any patient with nocturnal bowel movements, tenesmus, fecal urgency, heme-positive stool, and abdominal pain relieved by loose bowel movements must be investigated for IBD. A diagnosis is usually made by a colonoscopy and biopsy. Ulcerative colitis symptoms are usually more dramatic. Symptoms include rectal bleeding, weight loss, and persistent diarrhea and thus come to medical attention earlier. Again, this is a disease to be diagnosed and treated by the gastroenterologist.
Abdominal Wall Trigger Points Over 90% of patients with chronic pelvic pain have been found to have abdominal wall trigger points.122 By tensing the rectus abdominis muscles, trigger points may be better elucidated.123 These tender abdominal or pelvic muscles can be easily treated in pain therapy units by local infiltration or by a physical therapist who is well versed in pelvic floor therapy. The therapist can be useful in teaching the patient exercises that can help reduce the pain and supporting patient education efforts (e.g., explaining that the disease is not in the pelvis).
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Primary dysmenorrhea is defined as menstrual pain that is not associated with specific underlying pathology. Secondary dysmenorrhea is menstrual-associated pain that is due to an underlying pathologic process. Primary dysmenorrhea will present typically within the first 12 to 24 months after menarche. The onset of pain with menarche raises the possibility of obstructive müllerian anomaly. Increased levels of PGF2α have been observed in the menstrual fluid and endometrial tissue of women who are dysmenorrheic versus eumenorrheic women. Higher leukotriene levels are present in the myometrium and endometrium of adult women with dysmenorrhea. In half of adolescent girls between age 14 and 16 with oligomenorrhea, this menstrual problem persists at age 18. Premature pubarche may be associated with development of PCOS. Oligomenorrhea at age 15 was shown to be a better predictor of oligomenorrhea at age 18 than high testosterone, LH concentration, or polycystic ovaries on ultrasound. Hirsutism in adolescents is most commonly caused by PCOS. Life-style modification such as exercise and diet are important in adolescent girls with PCOS because behavioral changes may have a more long-lasting impact. In adolescents, the most common cause of AUB is anovulation. Teenagers presenting with menorrhagia (ovulatory AUB) must be assessed for bleeding disorders. If the bleeding is heavy but not emergent, an oral contraceptive pill may be taken every 8 to 12 hours until the bleeding has stopped and then tapered to one pill per day. This dosage may be increased to one pill every 4 to 6 hours. Patients with severe hemorrhage or inability to take medications orally can be given intravenous conjugated estrogens 25 mg every 4 hours for 24 hours or less if bleeding stops.
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When detected during infancy, the imperforate hymen presents as a mucocele. Evaluation of the external genitalia in a perimenarchal girl reveals a thin bulging hymen that may have a bluish hue secondary to the obstructed blood. In 85% to 90% of cases of androgen insensitivity syndrome, a mutation may be found in the androgen receptor gene. Female athletes are particularly vulnerable to eating disorders. The female athletic triad is the combination of amenorrhea, eating disorder, and osteopenia. Chronic problems of binge eating and purging include enlargement of the parotid gland, mouth sores, eroded dental enamel, and osteoporosis. The focus of the physical examination of patients with an eating disorder is measurement of height and weight, orthostatic blood pressure, and pulse. The endocrine abnormalities noted in patients with anorexia nervosa include low estradiol and gonadotropin levels, high cortisol levels, and normal prolactin, TSH, and free thyroxine (T4) levels; the reverse T3 is high and T3 levels are low. Nearly one third of ovarian masses that are surgically treated in young children have torsion. Risk factors for development of ovarian torsion are prior existence of an ovarian mass or cyst and prior pelvic surgeries. The goal of surgery in patients with ovarian torsion is “detorsion” and possible salvage of the ovary. Ovariopexy seems to be indicated in cases of repeat or bilateral ovarian torsion, prior loss of adnexa, or abnormally elongated utero-ovarian ligament. Endometriosis is a common cause of chronic pelvic pain in adolescent girls. Most adolescent girls with endometriosis have stage 1 disease.
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88. Graif M, Itzchak Y: Sonographic evaluation of ovarian torsion in childhood and adolescence. Am J Roentgenol 150:647–649, 1988. 89. Quillin SP, Siegel MJ: Transabdominal color Doppler ultrasonography of the painful adolescent ovary. J Ultrasound Med 13:549–555, 1994. 90. Lee EJ, Kwon HC, Joo HJ, et al: Diagnosis of ovarian torsion with color Doppler sonography: Depiction of twisted vascular pedicle. J Ultrasound Med 17:83–89, 1998. 91. Pena JE, Ufberg D, Cooney N, Denis AL: Usefulness of Doppler sonography in the diagnosis of ovarian torsion. Fertil Steril 73:1047–1050, 2000. 92. Hamper UM, DeJong MR, Caskey CI, Sheth S: Power Doppler imaging: Clinical experience and correlation with color Doppler US and other imaging modalities. Radiographics 17:499–513, 1997. 93. Zweizig S, Perron J, Grubb D, Mishell Jr DR: Conservative management of adnexal torsion. Am J Obstet Gynecol 168:1791–1795, 1993. 94. Oelsner G, Bider D, Goldenberg M, et al: Long-term follow-up of the twisted ischemic adnexa managed by detorsion. Fertil Steril 60:976–979, 1993. 95. Cohen SB, Oelsner G, Seidman DS, et al: Laparoscopic detorsion allows sparing of the twisted ischemic adnexa. J Am Assoc Gynecol Laparosc 6:139–143, 1999. 96. Templeman C, Hertweck SP, Fallat ME: The clinical course of unresected ovarian torsion. J Pediatr Surg 35:1385–1387, 2000. 97. Grunewald B, Keating J, Brown S: Asynchronous ovarian torsion—the case for prophylactic oophoropexy. Postgrad Med J 69:318–319, 1993. 98. Crouch NS, Gyampoh B, Cutner AS, Creighton SM: Ovarian torsion: To pex or not to pex? Case report and review of the literature. J Pediatr Adolesc Gynecol 16:381–384, 2003. 99. Germain M, Rarick T, Robins E: Management of intermittent ovarian torsion by laparoscopic oophoropexy. Obstet Gynecol 88:715–717, 1996. 100. Wyllie R, Kay M: Causes of recurrent abdominal pain. Clin Pediatr (Phila) 32:369–371, 1993. 101. Apply J, Nash N: RAP-field survey of disease in childhood. Arch Dis Child 33:165, 1958. 102. Poole SR: Recurrent abdominal pain in childhood and adolescence. Am Fam Physician 30:131–137, 1984. 103. Goldstein DP, deCholnoky C, Leventhal JM, Emans SJ: New insights into the old problem of chronic pelvic pain. J Pediatr Surg 14:675–680, 1979. 104. Vercellini P, Fedele L, Arcaini L, et al: Laparoscopy in the diagnosis of chronic pelvic pain in adolescent women. J Reprod Med 34:827–830, 1989. 105. Laufer MR, Goitein L, Bush M, et al: Prevalence of endometriosis in adolescent girls with chronic pelvic pain not responding to conventional therapy. J Pediatr Adolesc Gynecol 10:199–202, 1997. 106. Reese KA, Reddy S, Rock JA: Endometriosis in an adolescent population: The Emory experience. J Pediatr Adolesc Gynecol 9:125–128, 1996. 107. Chatman DL, Ward AB: Endometriosis in adolescents. J Reprod Med 27:156–160, 1982. 108. Sanfilippo JS, Wakim NG, Schikler KN, Yussman MA: Endometriosis in association with uterine anomaly. Am J Obstet Gynecol 154:39–43, 1986. 109. Laufer MR: Identification of clear vesicular lesions of atypical endometriosis: A new technique. Fertil Steril 68:739–740, 1997. 110. Redwine DB: Age-related evolution in color appearance of endometriosis. Fertil Steril 48:1062–1063, 1987. 111. Stripling MC, Martin DC, Chatman DL, et al: Subtle appearance of pelvic endometriosis. Fertil Steril 49:427–431, 1988. 112. Sutton CJ, Ewen SP, Whitelaw N, Haines P: Prospective, randomized, double-blind, controlled trial of laser laparoscopy in the treatment of pelvic pain associated with minimal, mild, and moderate endometriosis. Fertil Steril 62:696–700, 1994. 113. Selak V, Farquhar C, Prentice A, Singla A: Danazol for pelvic pain associated with endometriosis. Cochrane Database System Rev 2006;CD000068. 114. Rome ES, Moszczenski SA, Craighill M, et al: A clinical pathway for pelvic inflammatory disease for use on an inpatient service. Clin Perform Qual Health Care 3:185–196, 1995.
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Section 2 Pediatric and Adolescent Disorders 115. Webster RB, DiPalma JA, Gremse DA: Lactose maldigestion and recurrent abdominal pain in children. Dig Dis Sci 40:1506–1510, 1995. 116. Feldman W, McGrath P, Hodgson C, et al: The use of dietary fiber in the management of simple, childhood, idiopathic, recurrent, abdominal pain. Results in a prospective, double-blind, randomized, controlled trial. Am J Dis Child 139:1216–1218, 1985. 117. Hyams JS, Burke G, Davis PM, et al: Abdominal pain and irritable bowel syndrome in adolescents: A community-based study. J Pediatr 129:220–226, 1996. 118. Hyams JS, Treem WR, Justinich CJ, et al: Characterization of symptoms in children with recurrent abdominal pain: Resemblance to irritable bowel syndrome. J Pediatr Gastroenterol Nutr 20:209–214, 1995.
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119. Van Ginkel R, Voskuijl WP, Benninga MA, et al: Alterations in rectal sensitivity and motility in childhood irritable bowel syndrome. Gastroenterology. 120:31–38, 2001. 120. Hait L, Bousvaros A, Grand R: Pediatric inflammatory bowel disease: What children can teach adults. Inflam Bowel Dis 11:519–527, 2005. 121. Wyllie R, Sarigol S: The treatment of inflammatory bowel disease in children. Clin Pediatr (Phila) 37:421–425, 1998. 122. Slocumb JC: Neurological factors in chronic pelvic pain: Trigger points and the abdominal pelvic pain syndrome. Am J Obstet Gynecol 149:536–543, 1984. 123. Thomson WH, Dawes RF, Carter SS: Abdominal wall tenderness: A useful sign in chronic abdominal pain. Br J Surg 78:223–225, 1991.
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Section 3 Adult Reproductive Endocrinology Chapter
15
Polycystic Ovary Syndrome John K. Park, Tammy L. Loucks, and Sarah L. Berga
INTRODUCTION Polycystic ovary syndrome (PCOS) is a complex, multidimensional disorder resulting in defects in reproduction and metabolism. Although one of the primary characteristic of PCOS is the presence of multiple cysts on the ovaries, this syndrome involves far more than the ovary. The complexity of the syndrome is reflected in the wide range of its clinical manifestations, most notably insulin resistance, obesity, irregular menses, and signs of hyperandrogenism, such as hirsutism and acne. In 1935, Stein and Leventhal described patients who had a constellation of amenorrhea, infertility, and enlarged, polycystic ovaries.1 They found that bilateral ovarian wedge resection resulted in regular menses and even pregnancy in some. They reasoned that the thickened tunica was preventing follicles from reaching the surface of the ovary, resulting in the classic appearance of an enlarged ovary with multiple follicles beneath the cortex. Today we know that the mere finding of a polycystic-appearing ovary is not pathognomonic of PCOS, because many females without the disorder will have similar ovarian morphology.2,3
DIAGNOSTIC CRITERIA In 1990, a conference on PCOS sponsored by the National Institutes of Health (NIH) led to diagnostic criteria based on a majority opinion of conference participants.4 The criteria included: hyperandrogenism and/or hyperandrogenemia, chronic anovulation, and exclusion of other known disorders. In 2003, the European Society of Human Reproduction and Embryology (ESHRE)/American Society of Reproductive Medicine (ASRM)sponsored PCOS consensus workshop in Rotterdam revised the diagnostic criteria for PCOS.5 The revised criteria state that PCOS remains a diagnosis of exclusion, but that two out of the following three criteria must be present: (1) oligo-ovulation or anovulation, (2) hyperandrogenism and/or hyperandrogenemia, and (3) polycystic ovaries. The differential diagnosis should include other causes of hyperandrogenism and menstrual dysfunction, such as nonclassic congenital adrenal hyperplasia, hypothalamic amenorrhea, Cushing’s syndrome and disease, hyperprolactinemia, thyroid disease, acromegaly, and androgen-secreting neoplasms of the ovary or adrenal gland.
PREVALENCE The prevalence of PCOS is estimated to be 4% to 12% of reproductive-age women. The largest U.S. study on PCOS
prevalence was published in 1998.6 Out of 277 women included in the study, 4.0% had PCOS as defined by the 1990 NIH criteria. The prevalence was 4.7% for white women and 3.4% for black women. The inclusion of polycystic ovaries in the 2003 Rotterdam criteria calls for re-evaluation of the prevalence of PCOS, because 21% to 23% of normal women have polycysticappearing ovaries on ultrasound.2,3
CLINICAL PRESENTATION Typical presenting complaints for women with PCOS involve manifestations of hyperandrogenism, menstrual irregularity, and infertility. PCOS is characterized by phenotypic heterogeneity and therefore not all parameters of the syndrome will be found in individual patients.
Hyperandrogenism Clinical manifestations of hyperandrogenemia include hirsutism, acne, and male pattern alopecia. Hirsutism is defined as the growth of coarse, pigmented hairs in androgen-dependent areas such as the face, chest, back, and lower abdomen. Approximately 80% of hirsute patients will have PCOS.7 The modified Ferriman-Gallway scoring system can be used for clinical assessment of hirsutism. This was originally used in the United Kingdom for a population of presumably white women, and scores hair growth in nine body areas from 0 (absence of terminal hairs) to 4 (extensive terminal hair growth).8 Sex hair growth differs among various ethnic and genetic groups, being decreased in Asians, even when high androgen levels are present.9 Other hyperandrogenic manifestations commonly found in PCOS patients include acne and alopecia.10,11 Acne is a result of androgen stimulation of the pilosebaceous unit with increased skin oiliness.10 Cela and colleagues investigated a multiethnic group of 89 women who presented with androgenic alopecia and found that 67% had polycystic ovaries, compared to 27% of controls.11 In addition, women with alopecia had higher androgen levels and a higher prevalence of hirsutism.
Obesity Obesity is very common in PCOS, with the android pattern present in approximately 44% of women with PCOS.12 This central obesity is more characteristic of PCOS, because these patients have an increased waist-to-hip ratio compared to obese women without PCOS.13 Hyperinsulinemia may stimulate central adiposity, which, in turn, exacerbates underlying or
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Section 3 Adult Reproductive Endocrinology latent insulin resistance.14 It has been shown that obese women with PCOS have greater insulin resistance than weight-matched controls.15
Acanthosis Nigricans Acanthosis nigricans is a dermatologic condition of hyperkeratosis and increased skin pigmentation with raised, symmetric, darkened, velvety plaques that commonly appear on the nape of the neck. It can also be found in the axilla, groin, and other intertriginous areas of the body. This skin finding is a common manifestation of insulin resistance in patients with PCOS. Mor and coworkers found that acanthosis nigricans is more likely to be found in PCOS patients with insulin resistance compared to PCOS patients without insulin resistance (OR = 6.0, P < 0.5).16 The elevated insulin level has a mitogenic effect on basal cells of the epidermis, making acanthosis nigricans a relatively specific clinical marker of insulin resistance.17 Other pathologic conditions associated with acanthosis nigricans include insulinoma and malignant disease, especially adenocarcinoma of the stomach.
Reproductive Aberration
Polycystic Ovarian Morphology The Rotterdam ESHRE/ASRM-sponsored PCOS consensus workshop group included the polycystic morphology of the ovary as one of the diagnostic criteria for the syndrome.5 A polycystic ovary is defined as having 12 or more follicles in one ovary measuring 2 to 9 mm in diameter, and/or increased ovarian volume of greater than 10 mL, which is the maximum size of a normal ovary3 (Fig. 15-1). This definition should not be substituted with a subjective appearance of a polycystic ovary. The classic image is that of an enlarged ovary containing an increased number of small follicles around the periphery of the cortex (i.e., a string of pearls) with a bright echogenic stroma. The characteristic increase in stromal volume differentiates the polycystic ovary from a multifollicular ovary.3 The follicle distribution is omitted from the definition of a polycystic ovary, as well as the increase in stromal echogenicity and volume, but ovarian volume has been shown to be a good surrogate for stromal volume.27 Oral contraceptives modify ovarian morphology; thus the definition of a polycystic ovary does not apply to women taking these medications. When there is a dominant follicle (>10 mm) or a corpus luteum, the ultrasound should be repeated during the early follicular phase of the next cycle.
Irregular Menses
Some of the menstrual abnormalities seen with chronic anovulation include secondary amenorrhea, oligomenorrhea, and dysfunctional uterine bleeding. Menarche typically begins at a normal or early age, but the menstrual irregularities often seen in adolescence may never resolve for the PCOS patient. The irregular menses may be masked in PCOS patients if they are on oral contraceptives. Infertility
PCOS is the most common cause of anovulatory infertility, which often serves as the impetus for the patient to seek medical attention. These patients often present with frustration over the sudden, irregular nature of their menstrual cycles after having many years of predictable cycles while using oral contraceptives. Patients may be further aggravated by false-positive urinary ovulation predictor tests due to chronic elevation in luteinizing hormone (LH).
PATHOGENESIS Altered Gonadotropin Secretion One of the well-described features of PCOS is an increase in LH and relative decrease in follicle stimulating hormone (FSH).28 The relative decrease in FSH is the chief cause of anovulation, because increasing FSH will lead to folliculogenesis. The pulsatile secretion of LH from the pituitary is increased in amplitude and frequency in PCOS.29 In addition, the pituitary has a greater LH response to gonadotropin-releasing hormone (GnRH) compared with normal women.29,30 Elevations in LH could be secondary to
Miscarriage
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The risk of a first-trimester spontaneous abortion (i.e., miscarriage) is reported to be significantly higher for patients with PCOS than in normal women. The spontaneous abortion rate in PCOS is reported to be 30%.18 In comparison, retrospective studies find the risk of spontaneous abortion to be 5% to 14% for normal women.19,20 Of patients with recurrent miscarriage, 36% to 82% have polycystic ovaries.18,21,22 Several explanations have been offered. For example, Homburg and colleagues demonstrated that high concentrations of LH during the follicular phase in women with polycystic ovaries have a deleterious effect on rates of conception and are associated with early pregnancy loss.23 In another study, those with elevated LH levels had a 65% miscarriage rate compared to 12% of pregnancies with normal LH levels.24 Elevated serum androgen levels, obesity, and hyperinsulinemia have also been implicated as risk factors for early pregnancy loss.25,26
Figure 15-1 The classic image of polycystic ovary syndrome; an enlarged ovary containing an increased number of small follicles around the periphery of the cortex, resembling a string of pearls, along with a bright echogenic stroma.
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Chapter 15 Polycystic Ovary Syndrome increased GnRH pulse frequency, stimulatory factors other than GnRH, or a combination of these effects. The pulsatile secretion of GnRH cannot be studied in humans, so it must be inferred by detecting peripheral LH patterns. A study of PCOS women by Berga and colleagues found increased pulse frequency and amplitude for LH and α-subunit, providing evidence for aberrant increases in GnRH pulse frequency (Fig. 15-2).29 Furthermore, increased GnRH pulse frequency in rats has been shown to increase LHβ gene expression.31 Elevated LH is not caused by altered pituitary sensitivity to GnRH; GnRH receptor blockade resulted in similar LH decreases in PCOS and normal women.32 These findings suggest a derangement of the hypothalamicpituitary axis, which appears to play a major role; many of the cardinal features of PCOS can be traced to alterations in gonadotropins. The basis for decreased FSH secretion in PCOS has not been determined, although the negative feedback effect of chronic unopposed estrogen secretion in these women has been implicated as a mechanism.33
Altered GnRH Drive Neuroanatomic Considerations
The GnRH pulse generator refers to the synchronized pulsatile secretion of GnRH from neurons that are widely distributed in
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the medial basal hypothalamus. GnRH is synthesized in neuronal cell bodies that have migrated during fetal life from the olfactory placode to the hypothalamus and is secreted from neuroendocrine terminals localized in the median eminence. Knobil conducted experiments with the Rhesus monkey to establish that the GnRH system exhibits rhythmic electrical behavior in the arcuate nucleus of the medial basal hypothalamus.34 There was remarkable synchrony between pulses of GnRH in the portal blood and LH pulses in peripheral blood. This phenomenon was later studied in isolated human medial basal hypothalamus where GnRH pulses were found to occur at a frequency of 60 to 100 minutes.35 Thus, the GnRH neurons per se, with their intrinsic pulsatile secretion, appear to constitute the GnRH pulse generator. There is compelling evidence that non-neuronal cells, such as glial and endothelial cells, regulate GnRH secretion in the median eminence. Glial processes belonging to either astrocytes or tanycytes separate GnRH nerve endings from the pericapillary space in the median eminence and, through signaling molecules such as nitric oxide, play a role in regulation of GnRH secretion into pituitary portal blood vessels.36,37 The secretion of GnRH into the portal vasculature also appears to be regulated by dynamic remodeling of GnRH neurovascular junctions. Morphologic plasticity of the median eminence during the menstrual cycle has been demonstrated, where the maximal
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Figure 15-2 24-hour concentration profiles of LH (top) and α-subunit (bottom) in an eumenorrheic woman (EW)(left), studied in the follicular phase (day 2) and in a woman with hyperandrogenic anovulation/polycystic ovary syndrome (PCOS, right). (Data from Berga S, Guzick D, Winters S: Increased luteinizing hormone and α-subunit secretion in women with hyperandrogenic anovulation. J Clin Endocrinol Metab 77:895–901, 1993.)
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Mellon and coworkers developed a cell line of immortalized hypothalamic GnRH neurons (GT1 cells) that were determined to have an inherent ability to secrete GnRH in a pulsatile fashion.40 The development of GnRH cell lines, such as the GT1 cells, has permitted numerous studies to identify putative factors that regulate pulsatile GnRH secretion. Substances implicated in the modulation of the GnRH pulse generator include norepinephrine, dopamine, insulin-like growth factor I (IGF-I), γ-aminobutyric acid (GABA), and opioids, among others. There also appears to be an autocrine regulation of GnRH release, because GT1 cells themselves express GnRH receptors. The activation of GnRH receptors enhances action potentials, heightens synchronization of neuronal activities, and results in pulsatile release of GnRH. In Vivo GnRH Neuroregulation in PCOS
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The GnRH pulse generator in PCOS patients is intrinsically faster, and the frequency is less likely to be suppressed with continuous estrogen and progesterone treatment.40 A persistently rapid GnRH pulse generator would increase LH secretion and could suppress FSH levels low enough to prevent folliculogenesis. Increased central adrenergic tone has been implicated as a cause of the aberrations of GnRH and gonadotropin secretion in PCOS. One possible mechanism is the increase in local blood flow and permeability of the portal vascular system, permitting the entry of increased amounts of GnRH.41 Dopamine injection into the third ventricle led to a rapid increase in GnRH and prolactin inhibitory factor in portal blood, suggesting dopaminemediated regulation of GnRH and prolactin inhibitory factor.42 The identification of β1-adrenergic and D1-dopaminergic receptors on GT1 GnRH neurons provides a mechanism by which norepinephrine and dopamine could regulate gonadotropin release via direct synapses on GnRH neurons.43 Other studies have examined the effect of dopamine on immunoreactive LH. Dopamine exerts an inhibitory effect on LH secretion in normally cycling women44 and also has been shown to lower circulating LH in PCOS patients.45 It has been suggested that an impairment of the dopaminergic inhibitory activity on LH secretion leads to the increased frequency of LH pulses seen in PCOS women.46 In fact, the dopamine agonist bromocriptine has been shown to lower circulating LH and improve menstrual function in normoprolactinemic PCOS women.47 This finding has not been consistently demonstrated, as Lobo and coworkers did not find an increase in the ratio of bioactive to immunoreactive LH in response to dopamine alone or a dopamine-carbidopa combination, and concluded that dopamine did not play a critical role in LH secretion.48 The role of IGF-I in modulation of GnRH cells has also been investigated. IGF-I regulates growth, differentiation, survival, and reproductive function. The IGF receptor is a tyrosine kinase receptor located in the periphery and central nervous system, including the median eminence.49 Mouse studies have shown that IGF-I mRNA in the hypothalamus increases through peripubertal and adult development.50 IGF-I was found to stimulate GnRH gene expression in postnatal and peripubertal
mice.50 Another study using the GT1 cell line demonstrated that IGF-I treatment caused a significant increase in GnRH nuclear primary transcript levels and cytoplasmic mRNA.51 In PCOS women, an increased ratio of IGF-I to IGF binding proteins correlated significantly with increased concentrations of circulating LH.30 These findings suggest that IGF-I can modulate GnRH neurons by inducing gene expression, resulting in more circulating LH. Other substances found to affect GnRH and LH secretion include GABA and opioids. GABA may tonically inhibit LH secretion, as evidenced by an increase in LH secondary to a GABA-A receptor blocking drug, bicuculline.52 Naloxone is an opioid antagonist that has been shown to increase luteal phase LH, suggesting that opiates have an inhibitory effect on pituitary gonadotropins.53
Hyperandrogenemia Circulating androgens are elevated in PCOS, with contributions from the ovary and adrenal glands. The elevated androgens can only be partially suppressed with combination oral contraceptive therapy. Daniels and Berga treated PCOS women with 3 weeks of combination oral contraceptives and found that androstenedione levels remained significantly higher compared to treated controls.40 Pulse frequency of LH was suppressed in both PCOS women and controls, but the frequency remained significantly higher in PCOS patients (Fig. 15-3). This suggests reduced sensitivity of the GnRH pulse generator to suppression by sex steroids. The authors also suggest that the GnRH drive in PCOS women may be intrinsically and irreversibly faster than in eumenorrheic women. GnRH output may be affected by peripheral androgens. Androgen blockade restores hypothalamic sensitivity to feedback inhibition by ovarian steroids.54 Administration of estrogen and progesterone to PCOS women and controls pretreated with the anti-androgen flutamide demonstrated similar reductions in LH pulse frequency. Theca Cell Function
Ovarian hyperandrogenism is driven by LH acting on theca cells, and the effect is amplified by the increased sensitivity of PCOS theca cells to LH.55 Hyperandrogenism may also result from dysregulation of the androgen-producing enzyme P450c17, which has 17α-hydroxylase and 17,20-lyase activity. The dysregulation appears to be an intrinsic abnormality of P450c17, but autocrine/paracrine factors may also be involved.56 Insulin and IGF have also been shown to play a role in ovarian androgen production. Receptors for insulin, IGF-I, and IGF-II have been localized to the theca compartment of ovaries from normal and PCOS patients.57,58 When given IGF-I, IGF-II, and insulin, thecal cell cultures from euandrogenic women produced increased androgens, and the effect was potentiated when LH was added.57,59 Ovarian stroma from hyperandrogenic patients also released more androstenedione and testosterone in response to insulin, however, no synergy was found between insulin and LH.60 In contrast, in vivo studies do not find significant increases in androgen secretion in PCOS or normal women despite considerable increases in insulin levels. Dunaif and Graf studied PCOS and normal patients undergoing evaluation with the hyperinsulinemic euglycemic clamp, and found that insulin
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Figure 15-3 Representative 12-hour pulse patterns in two women with polycystic ovary syndrome/hyperandrogenic anovulation are shown on the right side and those from eumenorrheic women on the left. ON means subjects were studied on day 21 of a combination oral contraceptive containing 35 μg of ethinyl estradiol and 1 mg of norethindrone. OFF refers to day 7 after cessation of the combination oral contraceptive. (Data from Daniels T, Berga S: Resistance of gonadotropin releasing hormone drive to sex steroid-induced suppression in hyperandrogenic anovulation. J Clin Endocrinol Metab 82:4179–4183, 1997.)
decreased androgens in PCOS women and did not increase androgens in normal women.13 This argues against a simple causal relationship between hyperinsulinemia and hyperandrogenism, but a role for insulin is strongly suggested by the observation that reduction of hyperinsulinemia is associated with decreases in serum androgens. Treatment of PCOS patients with metformin, which reduces hepatic glucose production and secondarily lowers insulin, has been shown to decrease levels of testosterone, dehydroepiandrosterone sulfate (DHEAS), and androstenedione.61 Adrenal Function
Excess adrenal androgen production is seen in PCOS women, with a 48% to 64% increase in DHEAS and 11βhydroxyandrostenedione.9 The underlying cause of elevated
adrenal androgens is yet to be elucidated, but PCOS women do not have increased corticotropin levels.62 Increased adrenal androgen production in PCOS is likely caused by either altered adrenal responsiveness to corticotropin or abnormal adrenal stimulation by factors other than corticotropin. A recent study by Moran and colleagues found that adrenal androgen excess in PCOS is associated with a greater 17α-hydroxylase activity in response to corticotropin.63 The cytochrome P450c17 (CYP17) gene regulates 17α-hydroxylase and 17,20-lyase activity. A defect in the P450c17 enzyme or in the regulation by autocrine/paracrine factors appears to be involved.56 Hyperinsulinemia may also play a role in adrenal androgen production in PCOS. PCOS patients treated with troglitazone experienced improvement in insulin resistance with a concomitant decrease in DHEAS levels, regardless of initial
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Section 3 Adult Reproductive Endocrinology DHEAS levels.64 Obese PCOS women treated with pioglitazone had significant improvement in insulin sensitivity with a decrease in corticotropin-stimulated androstenedione levels.65 These data support the notion that insulin enhances corticotropin-stimulated steroidogenesis.
Anovulation The cause of anovulation in PCOS patients has yet to be clarified. However, several observations about granulosa function have been described that may give insight into this process. Granulosa Cell Function
FSH levels are characteristically low in PCOS women, resulting in arrested follicular development. Insufficient granulosa cell aromatase activity was the basis of earlier studies that tried to explain poor follicular development, because follicular fluid estradiol concentrations were thought to be low. To the contrary, more recent studies found that PCOS granulosa cells are hyperresponsive to FSH in vitro, and estradiol concentrations from PCOS follicles and normal follicles are no different.66 A dose–response study in PCOS women demonstrated a significantly greater capacity for estradiol production in response to recombinant human FSH compared with normal women.67 The incremental response of serum estradiol was almost two times greater and considerably accelerated compared with that found in normal women. Van Der Meer and coworkers demonstrated that the accelerated estradiol production may simply be explained by the increased number of follicles.68 Another study of granulosa cells from polycystic ovaries discovered that there are more FSH receptors compared with cells from normal ovaries.69 Whether the increased estradiol responsiveness to FSH is due to increased number of follicles, increased granulosa cell sensitivity to FSH, or increased FSH receptor binding, women with PCOS appear to be susceptible to ovarian hyperstimulation in response to gonadotropins. Insulin has been investigated as a modulator of both theca and granulosa cell function. As noted earlier, insulin has been shown to augment the effect of LH on thecal cell androgen secretion. The effects of insulin on granulosa cells are less well known. In vitro studies have shown that insulin augments two actions of FSH on granulosa cells: basal production of estrogen and progesterone and induction of LH responsiveness.70,71 The latter effect results in further enhanced LH-stimulated steroid production of estradiol and progesterone. Willis and Franks showed that the effects of insulin were apparent at low concentrations, underscoring the fact that insulin acts via its own receptor and suggesting that the ovary is not insulin resistant.72 The premature responsiveness of granulosa cells to LH may lead to untimely differentiation of granulosa cells, resulting in premature arrest of follicular growth. This might explain the presence of the many 5- to 10-mm follicles commonly observed in PCOS ovaries containing steroidogenically active granulosa cells that do not progress spontaneously to the preovulatory stage.
Insulin Resistance Although 50% to 70% of PCOS patients have insulin
222 resistance,73 it is not one of the diagnostic criteria for PCOS. The
topic deservedly receives much attention because many of the clinical signs and symptoms of PCOS may be attributed to excess insulin exposure. The precise molecular basis for insulin resistance is unknown, but it appears to be a postreceptor defect.74 There is tissue specificity of insulin resistance in PCOS: muscle and adipose tissue are resistant; the ovaries, adrenals, liver, skin, and hair remain sensitive. The resistance to insulin in skeletal muscle and adipose tissue leads to a metabolic compromise of insulin function and glucose homeostasis, but there is preservation of the mitogenic and steroidogenic function in other tissues. The effect of hyperinsulinemia on the sensitive organs results in the downstream effects seen in PCOS, such as hirsutism,7 acanthosis nigricans,17 obesity,14 stimulation of androgen synthesis,57 increase in bioavailable androgens via decreased sex hormone-binding globulin (SHBG),75 and, potentially, modulation of LH secretion.60 In 1992, Hales and Barker proposed the concept that the environmental influence of undernutrition in early life increased the risk of type 2 diabetes in adulthood.76 They discovered a relationship between low birth weight and type 2 diabetes in men from England. The finding has been replicated in many different populations and ethnic groups, and the relationship has been extended to include the antecedent condition of insulin resistance.77 In the thrifty phenotype hypothesis, malnutrition serves as a fetal and infant insult that results in a state of nutritional thrift. The adaptations result in postnatal metabolic changes that prepare the individual for survival under poor nutritional conditions. One advantageous change is the development of insulin resistance in muscle and adipose tissue, with selective protection of brain growth and activity. The adaptations become detrimental when the postnatal environment changes to one of an overabundance of nutrients, resulting in obesity and diabetes. Recognition of insulin resistance can identify those who are most likely to respond to lifestyle and pharmacologic intervention. Insulin resistance puts patients at increased risk for certain metabolic sequelae, such as diabetes, hypertension, dyslipidemia, and cardiovascular disease.78 Insulin resistance is a component of the World Health Organization (WHO) definition of the metabolic syndrome, which is a cluster of risk factors for cardiovascular disease.79 The WHO defines the metabolic syndrome as the presence of glucose intolerance or insulin resistance, with at least two of the following: hypertension, dyslipidemia, obesity, and microalbuminuria. Women with PCOS are 4.4 times more likely to have the metabolic syndrome, so it becomes prudent to screen these patients, especially in those with insulin resistance.80
LONG-TERM CONSEQUENCES OF PCOS Metabolic Syndrome PCOS has many hallmarks of the metabolic syndrome and should no longer be considered a purely gynecologic disorder. However, the gynecologic symptoms may be one of the earliest manifestations of the metabolic syndrome in many young women. The early presentation affords a clinician the opportunity for diagnosis, counseling, and treatment to alter the risk profile for development of the metabolic syndrome or cardiovascular disease and to forestall or ameliorate the development of classical phenotypic features that compromise self-esteem.
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Chapter 15 Polycystic Ovary Syndrome Numerous studies have established that there is an increased risk of diabetes and cardiovascular disease in PCOS women. One third of PCOS patients have impaired glucose tolerance, and they also have a fivefold to tenfold greater risk for type 2 diabetes mellitus, regardless of ethnicity.73 By the time these patients reach menopause, they will have significantly more hypertension and diabetes compared to controls.81 Lipid abnormalities are also more prevalent in PCOS patients. There can be significant increases in total cholesterol, LDL cholesterol, and triglycerides and a decrease in HDL cholesterol compared to weight-matched controls.82 The dyslipidemia, impaired glucose intolerance, central obesity, hyperandrogenism, and hypertension seen in PCOS patients greatly increase the risk for cardiovascular disease. Based on this risk profile, women with PCOS have a sevenfold increased risk of myocardial infarction.83 Direct evidence for the increased cardiovascular risk was shown when women in their 40s with a history of PCOS were found to have subclinical atherosclerosis detected by carotid ultrasonography.84 PCOS women have also been found to have a higher prevalence of coronary artery and aortic calcification compared to age- and BMI-matched controls.80 Women with PCOS also have decreased global fibrinolytic capacity, suggesting the presence of a prothrombotic state, yet another risk for cardiovascular disease.85 Whether PCOS itself constitutes a risk factor independent of known risk factors remains to be elucidated. Despite the elevated risk of cardiovascular disease, a large retrospective study of almost 800 PCOS women in the United Kingdom did not find a markedly higher than average mortality from circulatory disease nor increased overall excess mortality.86
Cancer Women with PCOS have unopposed estrogen and are more likely to be obese, which leads to concerns about an increased risk for endometrial hyperplasia or malignancy. One long-term follow-up study of PCOS women in the United Kingdom found a significantly elevated risk of endometrial cancer, but no increased risk of breast cancer.87 The elevated risk of endometrial cancer may be a consequence of more than just unopposed estrogen in these patients. Hormone analyses from endometrial cancer patients reveal a 3.6-fold and 2.8-fold increased risk of endometrial cancer among premenopausal and postmenopausal women, respectively, who have high levels of androstenedione.88 The elevations in LH may have a role as well, because LH/hCG receptors are overexpressed in endometrial hyperplasia and carcinoma.89 The authors concluded that the overexpression of these receptors is a feature of endometrial disease developing in younger anovulatory women, including those with PCOS. An investigation into the possible risk of postmenopausal breast cancer in PCOS women was performed using data from the Iowa Women’s Health Study. This prospective cohort study received completed questionnaires from over 41,000 women aged 55 to 69 and found no increased risk for breast cancer in women with a history of PCOS.90
LABORATORY EVALUATION In addition to confirming elevations of androgens, the laboratory evaluation of PCOS should have the objective of excluding other causes of hyperandrogenic anovulation. Androgen-
producing tumors of the ovary and adrenal glands must be excluded. The adrenal glands contribute 98% of circulating DHEAS, whereas both the ovaries and adrenals contribute equal amounts of circulating testosterone and androstenedione. If total testosterone is greater than 200 ng/dL or DHEAS is greater than 7000 ng/dL, magnetic resonance imaging is warranted to identify the hormone-secreting lesion. Measuring 17α-hydroxyprogesterone will screen for 21-hydroxylase deficiency, the most common enzyme deficiency in nonclassic congenital adrenal hyperplasia. A 17-hydroxyprogesterone level of greater than 3 ng/mL is defined as elevated and should be followed by a corticotropin stimulation test, using 250 μg of synthetic corticotropin given intravenously after an overnight fast. A 1-hour increase in 17α-hydroxyprogesterone of more than 10 ng/mL is indicative of an enzyme defect in 21-hydroxylase. Cushing’s syndrome is extremely rare but may masquerade as PCOS, with hyperandrogenic anovulation and obesity. Those who have additional signs of Cushing’s syndrome, such as a moon facies, buffalo hump, abdominal striae, easy bruising, and proximal myopathy, should undergo screening with a 24-hour urinary free cortisol test. A normal value should be less than 100 μg. An abnormal value requires further testing with a dexamethasone suppression test. If suppression of cortisol does not occur, imaging studies should be performed to evaluate for adrenal hyperplasia, adrenal adenoma, or ectopic sources of corticotropin production. In the workup for anovulation, prolactinoma should be excluded. It is not uncommon to detect mild elevations in prolactin levels in PCOS patients, but high levels deserve magnetic resonance imaging of the pituitary to exclude prolactinoma. Thyroid-stimulating hormone (TSH) should be evaluated to exclude hyperthyroidism or hypothyroidism. Serum LH, FSH, and estradiol levels should be obtained to exclude hypothalamic amenorrhea or premature ovarian failure. A recent study suggested the combination of LH, FSH, and androstenedione levels provide the highest clinical utility in diagnostic sensitivity and specificity for PCOS.91
Diabetes Screen The 2003 Rotterdam PCOS consensus group recommends a 2-hour oral glucose tolerance test (OGTT) for obese PCOS patients and nonobese PCOS patients with risk factors for insulin resistance, such as family history of diabetes.5 Women with PCOS are at significantly increased risk for impaired glucose tolerance and type 2 diabetes compared to age-, weight-, and ethnicity-matched controls.92 The 2-hour OGTT is the preferred method for the detection of diabetes in PCOS patients due to its increased sensitivity over fasting plasma glucose, and it can be used to detect impaired glucose tolerance, an independent risk factor for diabetes that is associated with cardiovascular disease and increased mortality. If either the fasting glucose is 126 mg/dL or more, or the 2-hour level is 200 mg/dL or more, diabetes is detected and should be confirmed with a repeat test. Impaired fasting glucose is defined as a glucose level between 100 mg/dL and 126 mg/dL. Impaired glucose tolerance is defined as a 2-hour glucose level between 140 mg/dL and 200 mg/dL. Both impaired fasting glucose and impaired glucose tolerance are independent risk factors for the future development of diabetes.
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Section 3 Adult Reproductive Endocrinology Insulin Resistance Evaluation Defining insulin resistance is difficult because the concept is nebulous with no universally accepted diagnostic strategy. Generally speaking, insulin resistance is defined as “a subnormal biologic response to a given concentration of insulin.”93 The WHO defines insulin resistance as the lowest quartile of measures of insulin sensitivity.79 Once the diagnosis of insulin resistance is made, there are many implications given the numerous effects hyperinsulinemia may have on reproduction and metabolism. The gold standard for the diagnosis of insulin resistance is the hyperinsulinemic euglycemic clamp, which is expensive, timeconsuming, labor-intensive, and impractical for clinical use. Alternative tests have been developed and can be grouped by whether they involve insulin infusion, minimal modeling, or fasting. Tests that involve insulin infusion include the clamp techniques, as well as the insulin tolerance test and insulin sensitivity test. The minimal models require intravenous or oral administration of glucose only and include the frequently sampled intravenous glucose tolerance test and the OGTT. Insulin infusion dynamic tests and the frequently sampled glucose tolerance test are feasible only in the research setting due to the time and resources required. Fasting methods to assess insulin sensitivity include the homeostasis model assessment (HOMA), quantitative insulin sensitivity check index, and fasting glucose/insulin (G0/I0) ratio. The G0/I0 ratio was first described by Legro and coworkers as a measure of insulin sensitivity in white, obese PCOS women from Pennsylvania. The G0/I0 ratio detected insulin resistance
Ins > 20 ulU/mL Sens = 68.7 Spec = 93.2 AUC 0.874 ± 0.087
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with a sensitivity of 95% and specificity of 84% compared to the frequently sampled intravenous glucose tolerance test.94 Ducluzeau and coworkers later confirmed that the G0/I0 ratio is a predictor of insulin resiatnce in nonobese women as well.95 This study sought to identify the best markers of insulin resistance compared to the hyperinsulinemic euglycemic clamp. They measured serum SHBG, leptin, adiponectin, OGTT, and HOMA in addition to the G0/I0 ratio. The G0/I0 ratio emerged as the strongest independent parameter to appraise insulin resistance. The 2-hour OGTT can also be used to detect insulin resistance, with a 2-hour G0/I0 ratio of less than 1.0 suggestive of the diagnosis in the PCOS population.94 Correlation of insulin levels to glucose levels from the OGTT reveals how impaired glucose tolerance appears to be the result of decreased insulin sensitivity while impaired fasting glucose is a result of defective insulin secretion.96 One must be cognizant that there is considerable ethnic variability when screening for diabetes and insulin resistance. No normative values have been developed that are ethnicityspecific. Kauffman and colleagues studied white and Mexican American women with PCOS and found differing values for G0/I0 ratios to detect insulin resistance in the two populations.97 A fasting insulin greater than 20 μU/mL and G0/I0 ratio less than 7.2 detected insulin resistance in white women; a fasting insulin greater than 23 μU/mL and G0/I0 ratio less than 4.0 detected insulin resistance in Mexican American women (Fig. 15-4). In the clinical setting, the 2-hour OGTT that measures both fasting and postprandial glucose and insulin levels will yield the most information about glucose intolerance and
60 40
G/I < 4.0 Sens = 78.9 Spec = 94.4 AUC 0.947 ± 0.039
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Figure 15-4 Receiver operating characteristic (ROC) curves for fasting insulin, glucose-to-insulin (G/I) ratio, and homeostasis model assessment (HOMA) values in white and Mexican American populations. If different cutoff values are implemented in each ethnic group, good sensitivity and specificity for each screening test is found. There is no statistical difference among each test of insulin resistance when applied to nonglucose-intolerant populations. (Data from Kauffman RP, Baker VM, DiMarino P, et al: Polycystic ovarian syndrome and insulin resistance in white and Mexican American women: A comparison of two distinct populations. Am J Obstet Gynecol 187:1362–1369, 2002.)
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Chapter 15 Polycystic Ovary Syndrome hyperinsulinemia. It is recommended that the 2-hour OGTT be used to screen for the metabolic syndrome in obese women with PCOS, as well as any nonobese women with PCOS who have risk factors for insulin resistance.98 It is also reasonable to obtain a fasting lipid profile in women suspected of having risk factors for cardiovascular disease.
TREATMENT There are many considerations when deciding on therapy for PCOS (Fig. 15-5). Identification of patient concerns is necessary when prioritizing goals and formulating a treatment plan. A combination of therapies may be warranted, and the practitioner should appropriately counsel the patient on treatment expectations. Amelioration of long-term health risks should be emphasized regardless of the primary complaints of the patient.
Weight Loss Weight reduction should be a major component of any treatment plan for the overweight patient (BMI 26 or greater). Any sustained improvement in weight should involve diet and exercise, and consultation with a nutritionist may be helpful for those with difficulty achieving weight reduction. Obese PCOS patients who achieve weight loss will have an increase in SHBG, decrease in free testosterone, and improvement in fasting insulin levels.99
Oral Contraceptives Combination oral contraceptives have been the mainstay of PCOS management for the patient not interested in conception. Contraceptives suppress pituitary LH and consequently reduce ovarian androgen secretion, increase SHBG, and reduce free testosterone, while regulating menses and reducing the risk of endometrial hyperplasia or malignancy. However, there may be mild attenuation of insulin sensitivity. Korytkowski and coworkers have shown that short-term use of combination oral contraceptives in PCOS women results in a small decrease in insulin sensitivity and no change in the baseline elevation in triglyceride levels.100 However, in normal women, combination oral contraceptives were shown to produce an even more pronounced decline in insulin sensitivity, along with a significant elevation in triglyceride levels. The longer-term effects of combination oral contraceptives on insulin sensitivity and lipoprotein profiles have not been well documented. PCOS women are at greater risk for the development of diabetes and cardiovascular disease, and further investigation into the safety of long-term hormonal therapy is needed.
Antiandrogens Antiandrogens are commonly used as an adjunct to oral contraceptive therapy for treatment of hirsutism, but they have also been found to improve ovulation and restore regular
Desires conception?
Yes
No
Diabetes or glucose intolerance?
No
Yes Anovulatory?
Anovulatory? Yes
• Anti-androgens • Oral contraceptives
Hirsutism or acne?
Yes No
Expectant management Oral contraceptives
No
Yes
Ovulation induction: • Clomiphene • Gonadotropins • Exercise • Weight loss • ? Insulin sensitizers
Ovarian hyperstimulation
Expectant management No
• Exercise • Weight loss • Insulin sensitizers
Yes
No
• Ovarian drilling • Aromatase inhibitors
Persistent hirsutism? Yes
• Further evaluation • Anti-androgens • Glucocorticoids • GnRH-agonist+ addback HRT
Dyslipidemia or glucose intolerance? Yes
• Nutritional counseling • Weight loss • Medication • Insulin sensitizers
Figure 15-5 Polycystic ovary syndrome treatment algorithm. (Data from Berga S: The obstetrician-gynecologist’s role in the practical management of polycystic ovary syndrome. Am J Obstet Gynecol 179:109S–113S, 1998.)
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Section 3 Adult Reproductive Endocrinology
Insulin-Sensitizing Agents
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Insulin-sensitizing agents have been shown to improve endocrine and reproductive abnormalities in PCOS. Metformin is the most thoroughly investigated insulin-lowering agent used in PCOS. It is a biguanide that primarily works by suppressing hepatic gluconeogenesis and, to a lesser degree, increasing peripheral insulin sensitivity (Fig. 15-6).103 Thiazolidinediones are peroxisome proliferator activating receptor agonists that improve peripheral insulin sensitivity but do not appear to have an effect on hepatic glucose production (see Fig. 15-6).103 This class of medications includes troglitazone, pioglitazone, and rosiglitazone. Troglitazone is the oldest but was removed from the market in 2000 due to hepatotoxicity. Rosiglitazone and pioglitazone are still available and appear to be safer. The role of insulinsensitizing agents is still an area of active investigation. Many studies have demonstrated the positive effects of metformin on the reproductive axis of PCOS patients, with one of the most comprehensive studies recently demonstrating a dramatic improvement after 6 months of treatment. Metformin administration to nonobese hyperandrogenic PCOS patients resulted in a reduction of (1) LH pulse amplitude; (2) androstenedione levels; (3) testosterone levels; (4) ovarian volume; and (5) Ferriman-Gallway scores. Menstrual cyclicity was also improved in most patients.104 The investigators did not determine if metformin increased the likelihood of ovulation or if FSH levels rose. Similarly, troglitazone-treated PCOS patients demonstrated improved ovulation, decreased hirsutism, decreased free testosterone level, and increased SHBG.105 Insulin-sensitizing agents have a favorable effect on hyperandrogenism by reducing LH secretion, thereby removing the main stimulus for pathologic ovarian and adrenal androgen production. The reduction in insulin levels elevates hepatic SHBG production, decreasing free androgen levels. The concurrent improvement in hyperinsulinemia and hyperandrogenemia conferred by the use of insulin-sensitizing agents may ameliorate hirsutism.
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menses. It is important to remember that all antiandrogens are teratogenic and pose a risk of feminizing a male fetus, and thus should be used along with an effective form of contraception. Spironolactone is an aldosterone antagonist and is the most commonly used adjunctive agent in the treatment of hirsutism. It competes for testosterone binding sites on the pilosebaceous unit, inhibits 5α-reductase, and inhibits androgen production by interfering with cytochrome P450.102 The potassium-sparing effect warrants judicious use in the patient on potassium supplementation or with preexisting hypertension. Flutamide is a nonsteroidal antiandrogen that competes for the androgen receptor. Anovulatory PCOS patients treated with flutamide experienced resumption of ovulation with restoration of normal ovarian appearance with one dominant follicle.103 This study also reported a reduction in plasma levels of LH, androstenedione, and testosterone. Liver toxicity is a rare but potentially serious side effect of flutamide. Finasteride is a potent inhibitor of 5α-reductase used for treatment of prostatic hyperplasia with promising results as a treatment for hirsutism. All antiandrogens should be used along with a form of contraception because they are teratogenic and pose a risk of feminizing a male fetus.
75
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Figure 15-6 Mean (±SE) percent changes within subjects in endogenous glucose production and the glucose disposal rate under hyperinsulinemic clamp conditions after 3 months of therapy with metformin or troglitazone. NS, not significant. (From Inzucchi S, Maggs D, Spollett G, et al: Efficacy and metabolic effects of metformin and troglitazone in type II diabetes mellitus. N Engl J Med 338:867–872, 1998. Copyright 1998 Massachusetts Medical Society. All rights reserved.)
The improvement in ovulation and menstrual cyclicity in patients treated with insulin-sensitizing agents suggests improved fertility. Indeed, spontaneous and clomipheneinduced ovulation rates in metformin-treated PCOS women are increased.106 Spontaneous ovulation occurred in 34% of those treated with 500 mg of metformin three times daily compared to only 4% in the placebo group. Clomiphene-induced ovulation occurred in 90% of women who received metformin compared to 8% who received placebo. For those who are clomipheneresistant, significant improvements in ovulation and pregnancy rates were reported in a randomized, double-blind, placebocontrolled trial for women pretreated with metformin.107 Troglitazone alone and the combination of troglitazone plus clomiphene is also associated with increased rates of ovulation and pregnancy in insulin-resistant women with PCOS.108 Though metformin is a category B medication, its use throughout pregnancy is becoming more attractive. In one retrospective study, Jakubowicz and colleagues found a significant reduction in the rate of early pregnancy loss for PCOS women who conceived while taking metformin and continued the agent throughout pregnancy. The rate of early pregnancy loss in the metformin group was 8.8% compared to 41.9% in controls. In the women with a prior history of miscarriage, the early loss rate was 11.1% for the metformin group compared with 58.3% in the control group.109 The efficacy of metformin for pregnancy loss is not yet clear, and safety data for this indication are lacking. Another possible beneficial effect of metformin administration during pregnancy is the significant reduction in gestational diabetes, as seen in one prospective cohort study.110
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Chapter 15 Polycystic Ovary Syndrome Randomized trials are needed before use of metformin is supported to prevent gestational diabetes in PCOS women with insulin resistance. Metformin should not be given to those with conditions associated with elevated lactate levels, such as renal or hepatic disease, because there is a risk of lactic acidosis with an associated mortality of 50%.111 Although most studies of metformin in PCOS used a dose of 500 mg three times daily, no studies have been performed to determine the optimal dosing regimen for improvement in insulin sensitivity, reduction of androgens, and resumption of ovulation. A dose–response study of type 2 diabetic patients demonstrated that the 2000 mg daily dose was optimal for improvement of glucose homeostasis,112 but the relevance of this dose to the PCOS population remains to be investigated. Metformin should be initiated in a stepwise approach, titrating the dose slowly over several weeks to minimize side effects. Most patients will experience gastrointestinal symptoms such as nausea, diarrhea, indigestion, and abdominal discomfort. Side effects will resolve in several days for most patients, which allow incremental dosing increases on a weekly basis up to a maximum dose of 1000 mg twice a day. Baseline serum creatinine should be obtained with yearly monitoring to avoid lactic acidosis. If metformin is being used to improve reproductive status rather than to correct hyperglycemia, reproductive parameters can be monitored. One would want to employ the lowest dose that results in ovulation for those strictly interested in conceiving. The optimal dose for amelioration of hyperandrogenic phenotype has not been established, and the outcome variables to monitor will be cosmetic sequelae or circulating androgen levels. There are no guidelines currently on the long-term use of metformin to prevent or improve health outcomes in patients with PCOS. One of the serious reactions to the thiazolidinediones is hepatotoxicity. Initiation of treatment requires baseline liver function studies along with periodic monitoring.
Ovarian Surgery Ovarian Wedge Resection
Ovarian wedge resection is a surgical procedure that has been found to restore both regular menses and ovulation in the majority of cases when used in PCOS patients. This procedure, originally performed by laparotomy, consists of removing a wedge of ovarian tissue and reconstructing the ovary. In the past, it was recommended for women who remained anovulatory despite therapy with clomiphene citrate, and many of the patients who became ovulatory also achieved pregnancy. Laparoscopic techniques for ovarian wedge resection have been described. The primary disadvantage of this approach is the formation of significant pelvic adhesions, which occurs in at least one third of the patients. The concern is that these adhesions might actually decrease fertility and increase the risk of pelvic pain. Another concern is that the restoration of ovulation is unlikely to be permanent, because the ovaries are not the causal agents in this complex systemic disorder. However, the actual long-term effectiveness of wedge resection has never been reported. Ovarian Drilling
A laparoscopic variant with similar results to ovarian wedge resection is called ovarian drilling (see Chapter 37). This
procedure involves making multiple punctures in the ovarian cortex and destroying ovarian tissue using unipolar electrosurgery or laser. The results and complications for this approach appear to be similar or slightly less than those for ovarian wedge resection, although a prospective, randomized study has never been done. There are additional concerns about long-term effects of ovarian drilling on ovarian function.
Hair Removal In women with significant hirsutism, removal of unwanted hair, especially on the face, chest, and abdomen, is often an important concern. Shaving, plucking, waxing and depilatories are the most common approaches used for temporary removal. These approaches do not induce coarser or faster hair growth, but must be repeated at frequent intervals. Electrolysis
Electrolysis, wherein a fine needle is inserted into each hair follicle and an electrical current is applied, is probably the most commonly used technique for permanent hair removal. Hair follicles must be treated individually, and several treatments may be needed to destroy the follicle. Usually, repeated treatments are required over a 12- to 18-month period. Possible side effects include pain, infection, hyperpigmentation or hypopigmentation, and keloid formation in susceptible women. Laser Hair Removal
Lasers and related intense pulsed light devices are other options for hair removal. These techniques work by emitting light at various wavelengths, energy output, and pulse widths that are selectively absorbed by darker structures. For this reason, laser hair removal works best for light-skinned people with dark hair. As with electrolysis, laser treatments for hair removal must be repeated. There remains some controversy over whether these techniques actually result in permanent destruction of hair follicles or simply retard the regrowth of new hair. Possible side effects, though uncommon, are related to damage to the surrounding healthy tissue in the form of scars, burns, redness, and swelling. These techniques are relatively expensive. Topical Eflornithine Hydrochloride
Eflornithine hydrochloride (Vaniqa) is a prescription-only topical cream approved by the U.S. Food and Drug Administration (FDA) for reducing and inhibiting the growth of unwanted facial hair. It was initially developed as an oral drug for the treatment of malignancies (for which it is ineffective) and is currently being used overseas to treat African trypanosomiasis (sleeping sickness). This drug works by irreversibly inhibiting ornithine decarboxylase, an enzyme that facilitates cell division in hair follicles. The cream is applied twice a day to areas of unwanted facial hair, and less than 1% is absorbed systemically. It is designated by the FDA as a pregnancy category C drug. Noticeable results are usually observed after 4 to 8 weeks of therapy. Application must be continued for as long as inhibition of hair growth is desired, although facial hair growth is reduced for up to 8 weeks after discontinuation.
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Section 3 Adult Reproductive Endocrinology SUMMARY
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PCOS is a complex disorder affecting multiple aspects of the endocrine system. Reproductive endocrinologists can no longer claim sole jurisdiction over this disease; patients may be presenting to internists, medical endocrinologists, and cardiologists for problems seemingly unrelated to the hypothalamicpituitary-ovarian axis. The underlying cause remains to be identified; there are several competing schools of thought. Some believe that abnormal hypothalamic drive is responsible; others hypothesize that hyperandrogenemia resulting from altered steroidogenesis is to blame. Another theory claims that insulin resistance is the key component, although others feel that insulin resistance better describes a subset of patients with PCOS. Indeed, multiple pathogenic mechanisms result in a PCOS picture. Treatment of PCOS is usually multifaceted, directed toward salient patient treatment goals while also aiming to diminish long-term risks of morbidity. When conception is desired, some forms of treatment are incongruous with others. For example, antiandrogens may be teratogenic, and HMG-CoA reductase inhibitors are contraindicated in those seeking conception. An idealized treatment algorithm is presented in Figure 15-5, which is likely to require revision as our understanding of the pathogenesis of PCOS improves.
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The diagnostic criteria for PCOS from the Rotterdam ESHRE/ASRM-Sponsored PCOS Consensus Workshop Group require two out of the following three criteria be present: (1) oligo-ovulation or anovulation, (2) hyperandrogenism and/or hyperandrogenemia, and (3) polycystic ovaries. A polycystic ovary is defined as having 12 or more follicles in one ovary measuring 2 to 9 mm in diameter and/or ovarian volume greater than 10 mL. PCOS patients have an increase in LH pulse frequency and amplitude and a decrease in FSH.
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GnRH neurons constitute the GnRH pulse generator. The GnRH pulse generator in PCOS patients is intrinsically faster, leading to increased LH secretion. This may also be the explanation for the relative reduction in FSH. Aberrant folliculogenesis and anovulation is due to the relative reduction in FSH. Ovarian sensitivity to FSH is preserved. GnRH secretion into portal blood may be regulated by glial and endothelial cells in addition to other neurotransmitters. Many substances are implicated in the modulation of the GnRH pulse generator, such as sex steroids, insulin, IGF-I, norepinephrine, dopamine, GABA, and opioids. Ovarian hyperandrogenism is driven by LH, and the effect is amplified by increased sensitivity to LH. The cause of excess adrenal androgen production is unknown, but hyperinsulinemia may play a role. From 50% to 70% of PCOS patients have insulin resistance. Although muscle and adipose tissue are insulin resistant, ovaries, adrenals, liver, skin, and hair remain sensitive. Insulin resistance may be the first manifestation of the metabolic syndrome in many PCOS patients. PCOS women are at increased risk for diabetes, dyslipidemia, cardiovascular disease, and endometrial cancer. To exclude other causes of hyperandrogenic anovulation, one should obtain levels of: testosterone, DHEAS, 17hydroxyprogesterone, and 24-hour urinary free cortisol if Cushing’s syndrome is suspected. Rarely, acromegaly may present as a PCOS-like picture. The 2-hour OGTT is the preferred method for diabetes detection. A fasting and 2-hour insulin level will detect insulin resistance or pancreatic insufficiency, respectively. Oral contraceptives plus anti-androgens are an effective therapy for patients with hirsutism and irregular menses. Insulin-lowering agents appear to be an effective adjunct for hyperinsulinemic women attempting conception. However, optimal dosing and safety profiles need further study.
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38. Prevot V, Croix D, Bouret S, et al: Definitive evidence for the existence of morphological plasticity in the external zone of the median eminence during the rat estrous cycle: Implication of neuroglio-endothelial interactions in gonadotropin-releasing hormone release. Neuroscience 94:809–819, 1999. 39. Wetsel WC, Valenca M, Merchenthaler I, et al: Intrinsic pulsatile secretory activity of immortalized luteinizing hormone-releasing hormone-secreting neurons. Proc Natl Acad Sci 89:4149–4153, 1992. 40. Daniels T, Berga S: Resistance of gonadotropin releasing hormone drive to sex steroid-induced suppression in hyperandrogenic anovulation. J Clin Endocrinol Metab 82:4179–4183, 1997. 41. Kalro BN, Loucks TL, Berga SL: Neuromodulation in polycystic ovary syndrome. Infertil Reprod Med Clin 14:529–555, 2003. 42. Kamberi IA, Mical RS, Porter JC: Hypophysial portal vessel infusion: In vivo demonstration of LRF, FRF, and PIF in pituitary stalk plasma. Endocrinology 89:1042–1046, 1971. 43. Findell PR, Wong KH, Jackman JK, Daniels DV: β1-Adrenergic and dopamine (D1) receptors coupled to adenylyl cyclase activation in GT1 gonadotropin-releasing hormone neurosecretory cells. Endocrinology 132:682–688, 1993. 44. Leblanc H, Lachelin GC, Abu-Fadil S, Yen SS: Effects of dopamine infusion on pituitary hormone secretion in humans. J Clin Endocrinol Metab 43:668–674, 1976. 45. Quigley ME, Rakoff JS, Yen SS: Increased luteinizing hormone sensitivity to dopamine inhibition in polycystic ovary syndrome. J Clin Endocrinol Metab 52:231–234, 1981. 46. Judd SJ, Rigg LA, Yen SS: The effects of ovariectomy and estrogen treatment on the dopamine inhibition of gonadotropin and prolactin release. J Clin Endocrinol Metab 49:182–184, 1979. 47. Spruce BA, Kendall-Taylor P, Dunlop W, et al: The effect of bromocriptine in the polycystic ovary syndrome. Clin Endocrinol 20:481–488, 1984. 48. Lobo R, Shoupe D, Chang SP, Campeau J: The control of bioactive luteinizing hormone secretion in women with polycystic ovary syndrome. Am J Obstet Gynecol 148:423–428, 1984. 49. Pons S, Torres-Aleman I: Estradiol modulates insulin-like growth factor I receptors and binding proteins in neurons from the hypthalamus. J Neuroendocrinol 5:267–271, 1993. 50. Daftary S, Gore A: Developmental changes in hypothalamic insulinlike growth factor-1: Relationship to gonadotropin-releasing hormone neurons. Endocrinology 144:2034–2045, 2003. 51. Longo KM, Sun Y, Gore A: Insulin-like growth factor-1 effects on gonadotropin-releasing hormone biosynthesis in GT1-7 cells. Endocrinology 139:1125–1132, 1998. 52. Roth C, Jung H, Kim K, et al: Involvement of γ amino butyric acid (GABA) in the postnatal function of the GnRH pulse generator as determined on the basis of GnRH and GnRH receptor gene expression in the hypothalamus and the pituitary. Exper Clin Endocrinol Diabetes 105:353–358, 1997. 53. Snowden EU, Khan-Dawood FS, Dawood MY: The effect of naloxone on endogenous opioid regulation of pituitary gonadotropins and prolactin during the menstrual cycle. J Clin Endocrinol Metab 59:298–302, 1984. 54. Eagleson C, Gingrich M, Pastor C, et al: Polycystic ovarian syndrome: Evidence that flutamide restores sensitivity of the gonadotropinreleasing hormone pulse generator to inhibition by estradiol and progesterone. J Clin Endocrinol Metab 85:4047–4052, 2000. 55. de Ziegler D, Steingold K, Cedars M, et al: Recovery of hormone secretion after chronic gonadotropin-releasing hormone agonist administration in women with polycystic ovarian disease. J Clin Endocrinol Metab 68:1111–1117, 1989. 56. Barnes R: Pathophysiology of ovarian steroid secretion in polycystic ovary syndrome. Semin Reprod Endocrinol 15:159–168, 1997. 57. Bergh C, Carlsson B, Olsson JH, et al: Regulation of androgen production in cultured human thecal cells by insulin-like growth factor I and insulin. Fertil Steril 59:323–331, 1993. 58. el-Roeiy A, Chen X, Roberts VJ, et al: Expression of the genes encoding the insulin-like growth factors (IGF-I and II), the IGF and insulin receptors, and IGF-binding proteins 1-6 and the localization of
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WHO Consultation, part 1: Diagnosis and classification of diabetes mellitus. WHO, 1999. www.who.int/diabetes/currentpublication/en Talbott E, Zborowski J, Rager J, et al: Evidence for an association between metabolic cardiovascular syndrome and coronary and aortic calcification among women with polycystic ovary syndrome. J Clin Endocrinol Metab 89:5454–5461, 2004. Dahlgren E, Johansson S, Lindstedt G, et al: Women with polycystic ovary syndrome wedge resected in 1956 to 1965: A long-term follow-up focusing on natural history and circulating hormones. Fertil Steril 57:505–513, 1992. Wild RA, Painter PC, Coulson PB, et al: Lipoprotein lipid concentrations and cardiovascular risk in women with polycystic ovary syndrome. J Clin Endocrinol Metab 61:946–951, 1985. Dahlgren E, Janson PO, Johansson S, et al: Polycystic ovary syndrome and risk for myocardial infarction. Evaluated from a risk factor model based on a prospective population study of women. Acta Obstet Gynecol Scand 71:599–604, 1992. Guzick S, Talbott E, Sutton-Tyrrell K, et al: Carotid atherosclerosis in women with polycystic ovary syndrome: Initial results from a casecontrol study. Am J Obstet Gynecol 174:1224–1229, 1996. Yildiz B, Haznedaroglu I, Kirazli S, Bayraktar M: Global fibrinolytic capacity is decreased in polycystic ovary syndrome, suggesting a prothrombotic state. J Clin Endocrinol Metab 87:3871–3875, 2002. Pierpoint T, McKeigue P, Isaacs A, et al: Mortality of women with polycystic ovary syndrome at long-term follow-up. J Clin Epidemiol 51:581–586, 1998. Wild S, Pierpoint T, Jacobs H, McKeigue P: Long-term consequences of polycystic ovary syndrome: Results of a 31-year follow-up study. Hum Fertil 3:101–105, 2000. Potischman N, Hoover R, Brinton L, et al: Case-control study of endogenous steroid hormones and endometrial cancer. J Natl Cancer Inst 88:1127–1135, 1996. Konishi I, Koshiyama M, Mandai M, et al: Increased expression of LH/hCG receptors in endometrial hyperplasia and carcinoma in anovulatory women. Gynecol Oncol 65:273–280,1997. Anderson K, Sellers T, Chen P, et al: Association of Stein-Leventhal syndrome with the incidence of postmenopausal breast carcinoma in a large prospective study of women in Iowa. Cancer 79:494–499, 1997. Koskinen P, Penttila T, Anttila L, et al: Optimal use of hormone determinations in the biochemical diagnosis of the polycystic ovary syndrome. Fertil Steril 65:517–522, 1996. Legro R, Kunselman A, Dodson W, Dunaif A: Prevalence and predictors of risk for type 2 diabetes mellitus and impaired glucose tolerance in polycystic ovary syndrome: A prospective, controlled study in 254 affected women. J Clin Endocrinol Metab 84:165–169, 1999. Moller DE, Flier JS: Insulin resistance—mechanisms, syndrome, and implications. NEJM 325:938–948, 1991. Legro R, Finegood D, Dunaif A: A fasting glucose to insulin ratio is a useful measure of insulin sensitivity in women with polycystic ovary syndrome. J Clin Endocrinol Metab 83:2694–2698, 1998. Ducluzeau P, Cousin P, Malvoisin E, et al: Glucose-to-insulin ratio rather than sex hormone-binding globulin and adiponectin levels is the best predictor of insulin resistance in nonobese women with polycystic ovary syndrome. J Clin Endocrinol Metab 88:3626–3631, 2003. Carnevale Schiance G, Rossi A, Sainaghi P, et al: The significance of impaired fasting glucose versus impaired glucose tolerance. Diabetes Care 26:1333–1337, 2003. Kauffman RP, Baker VM, DiMarino P, et al: Polycystic ovarian syndrome and insulin resistance in white and Mexian American women: A comparison of two distinct populations. Am J Obstet Gynecol 187:1362–1369, 2002. Legro R, Castracane VD, Kauffman RP: Detecting insulin resistance in polycystic ovary syndrome: Purposes and pitfalls. Obstet Gynecol Surv 59:141–154, 2004. Guzick D, Wing R, Smith D, et al: Endocrine consequences of weight loss in obese, hyperandrogenic, anovulatory women. Fertil Steril 61:598–604, 1994.
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Chapter 15 Polycystic Ovary Syndrome 100. Korytkowski M, Mokan M, Horwitz M, Berga S: Metabolic effects of oral contraceptives in women with polycystic ovary syndrome. J Clin Endocrinol Metab 80:3327–3334, 1995. 101. Cumming D, Yang J, Rebar R, Yen S: Treatment of hirsutism with spironolactone. JAMA 247:1295–1298, 1982. 102. De Leo V, Lanzetta D, D’Antona D, et al: Hormonal effects of flutamide in young women with polycystic ovary syndrome. J Clin Endocrinol Metab 83:99–102, 1998. 103. Inzucchi S, Maggs D, Spollett G, et al: Efficacy and metabolic effects of metformin and troglitazone in type II diabetes mellitus. NEJM 338:867–872, 1998. 104. Genazzani A, Battaglia C, Malavasi B, et al: Metformin administration modulates and restores luteinizing hormone spontaneous episodic secretion and ovarian function in nonobese patients with polycystic ovary syndrome. Fertil Steril 81:114–119, 2004. 105. Azziz R, Ehrmann D, Legro R, et al: Troglitazone improves ovulation and hirsutism in the polycystic ovary syndrome: A multicenter, double blind, placebo-controlled trial. J Clin Endocrinol Metab 86:1626–1632, 2001. 106. Nestler J, Daniela J, Evans W, Pasquali R: Effects of metformin on spontaneous and clomiphene-induced ovulation in the polycystic ovary syndrome. NEJM 338:1876–1880, 1998.
107. Vandermolen D, Ratts V, Evans W, et al: Metformin increases the ovulatory rate and pregnancy rate from clomiphene citrate in patients with polycystic ovary syndrome who are resistant to clomiphene citrate alone. Fertil Steril 75:310–315, 2001. 108. Mitwally M, Kuscu N, Yalcinkaya T: High ovulatory rates with use of troglitazone in clomiphene-resistant women with polycystic ovary syndrome. Hum Reprod 14:2700–2703, 1999. 109. Jakubowicz D, Iuorno M, Jakubowicz S, et al: Effects of metformin on early pregnancy loss in the polycystic ovary syndrome. J Clin Endocrinol Metab 87:524–529, 2002. 110. Glueck C, Wang P, Kobayashi S, et al: Metformin therapy throughout pregnancy reduces the development of gestational diabetes in women with polycystic ovary syndrome. Fertil Steril 77:520–525, 2002. 111. De Leo V, La Marca A, Petraglia F: Insulin-lowering agents in the management of polycystic ovary syndrome. Endocrine Rev 24:633–667, 2003. 112. Garber A, Duncan T, Goodman A, et al: Efficacy of metformin in type II diabetes: Results of a double-blind, placebo-controlled, dose–response trial. Am J Med 103:491–497, 1997.
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16
Amenorrhea J. Ricardo Loret de Mola
INTRODUCTION Disorders of the menstrual cycle are one of the most common reproductive problems seen in a gynecologic practice. The absence of a menstrual period is a frequent symptom of underlying pathology of either the reproductive tract or the hypothalamic-pituitary-ovarian axis. This chapter examines both primary and secondary amenorrhea. Although some of the etiologies for these two conditions overlap, the most common causes and thus the diagnostic approaches used for the two are very different. For this reason, primary and secondary amenorrhea are considered separately in terms of etiology, diagnosis, and management. Each section concludes with a comprehensive diagnostic approach.
DEFINITIONS In common medical usage, amenorrhea refers to the abnormal cessation of menses.1 Physiologic amenorrhea exists before puberty, during pregnancy and lactation, and after menopause. However, these physiologic causes are not included in the standard amenorrhea classifications. Amenorrhea can be divided into two major groups based on presentation: primary or secondary amenorrhea (Table 16-1).2,3 Although many of the causes of primary and secondary amenorrhea are similar, the most likely causes, and thus the diagnostic approach, are distinct.
is diagnosed depends on the presence or absence of secondary sexual characteristics. In the absence of increased growth or development of secondary sexual characteristics, primary amenorrhea is diagnosed when the patient has no menses by age 13. In the presence of normal growth and development of secondary sexual characteristics, the diagnosis of primary amenorrhea is reserved for patients who have no menstruation by age 15. The incidence of primary amenorrhea in the United States is less than 0.1%. The majority of patients with primary amenorrhea will be found to have either gonadal dysgenesis (49%) or müllerian agenesis (16%).4
Secondary Amenorrhea Secondary amenorrhea refers to cessation of menses after establishment of menstruation for reasons other than pregnancy, lactation, or menopause. By convention, the diagnosis is applied after menses have been absent for a length of time equivalent to at least 3 of the previous menstrual cycle intervals or 6 months. The incidence of secondary amenorrhea not due to pregnancy, lactation, or menopause is approximately 4%.5,6 Although the list of causes for amenorrhea is quite extensive (Table 16-2), it appears that this list will continue to grow or be modified as more sophisticated genetic testing becomes available and the genetic understanding of human disease expands. The majority of patients with amenorrhea will have premature ovarian failure, hyperprolactinemia, hypothalamic amenorrhea, or polycystic ovary syndrome (PCOS).
Primary Amenorrhea Primary amenorrhea is the absence of menstruation in a woman who has never menstruated. Because children do not normally menstruate before puberty, the age at which primary amenorrhea
Table 16-1 Definitions of Primary and Secondary Amenorrhea Primary Amenorrhea No menstruation in a woman who has never menstruated by • age 13 in the absence of growth and development of secondary sexual characteristics, or • age 15 with normal growth and development of secondary sexual characteristics Secondary Amenorrhea Any woman who has been regularly menstruating with the absence of menses for either ≥ 3 of the previous cycle intervals, or 6 months
Classification The most widely accepted classification of amenorrhea was published by the World Health Organization (WHO) and divides amenorrhea into three groups (Table 16-3).3 This WHO amenorrhea classification is designed to help the practicing clinician summarize the causes of amenorrhea to assist in evaluating the condition. Group I include individuals who lack endogenous estrogen production, in association with normal or low follicle-stimulating hormone (FSH) levels, and no evidence of hypothalamic-pituitary pathology or elevated prolactin levels. Group II is associated with evidence of estrogen production and normal levels of prolactin and FSH. Finally, Group III involves elevated serum FSH levels that indicate gonadal failure.7 Although amenorrhea can occur among patients with sexual ambiguity or virilization, it is rarely the cause for initial consultation.8
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Section 3 Adult Reproductive Endocrinology Table 16-2 Classification of Amenorrhea, Both Primary and Secondary3 I.
Anatomic defects (outflow tract) A. Müllerian agenesis (Mayer-Rokitansky-Küster-Hauser syndrome) B. Complete androgen resistance (testicular feminization) C. Intrauterine synechiae (Asherman syndrome) D. Imperforate hymen E. Transverse vaginal septum F. Cervical agenesis—isolated G. Cervical stenosis—iatrogenic H. Vaginal agenesis—isolated I. Endometrial hypoplasia or aplasia—congenital
II. Primary hypogonadism A. Gonadal dysgenesis 1. Abnormal karyotype (Incomplete gonadal dysgenesis) a. Turner syndrome 45,X b. Mosaicism 2. Normal karyotype a. Pure gonadal dysgenesis i. 46,XX ii. 46,XY (Swyer syndrome) B. Gonadal agenesis C. Enzymatic deficiency 1. 17α-Hydroxylase deficiency 2. 17,20-Lyase deficiency 3. Aromatase deficiency D. Premature ovarian failure 1. Idiopathic 2. Injury a. Chemotherapy b. Radiation c. Mumps oophoritis 3. Resistant ovary a. Idiopathic III. Hypothalamic causes A. Dysfunctional 1. Stress 2. Exercise 3. Nutrition-related a. Weight loss, diet, malnutrition b. Eating disorders (anorexia nervosa, bulimia) 4. Pseudocyesis B. Other disorders 1. Isolated gonadotropin deficiency a. Kallmann syndrome b. Idiopathic hypogonadotropic hypogonadism 2. Infection a. Tuberculosis b. Syphilis c. Encephalitis/meningitis d. Sarcoidosis 3. Chronic debilitating disease 4. Tumors a. Craniopharyngioma b. Germinoma c. Hamartoma d. Langerhans cell histiocytosis e. Teratoma f. Endodermal sinus tumor g. Metastatic carcinoma IV. Pituitary causes A. Tumors 1. Prolactinomas 2. Other hormone-secreting pituitary tumor (corticotropin, thyrotropinstimulating hormone, growth hormone, gonadotropin) a. Mutations of FSH receptor b. Mutations of LH receptor c. Fragile X syndrome 3. Autoimmune disease 4. Galactosemia V. Other endocrine gland disorders A. Adrenal disease 1. Adult-onset adrenal hyperplasia 2. Cushing syndrome B. Thyroid disease 1. Hypothyroidism 2. Hyperthyroidism
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Table 16-2 Classification of Amenorrhea, Both Primary and Secondary3—cont’d C. Ovarian tumors 1. Granulosa-theca cell tumors 2. Brenner tumors 3. Cystic teratomas 4. Mucinous/serous cystadenomas 5. Krukenberg tumors 6. Nonfunctional tumors (craniopharyngioma) 7. Metastatic carcinoma D. Space-occupying lesions 1. Empty sella 2. Arterial aneurysm E. Necrosis 1. Sheehan syndrome 2. Panhypopituitarism F. Inflammatory/infiltrative 1. Sarcoidosis 2. Hemochromatosis 3. Lymphocytic hypophysitis G. Gonadotropin mutations (FSH) VI. Multifactorial causes A. Polycystic ovary syndrome
Table 16-3 World Health Organization (WHO) Classification of Amenorrhea Characteristic
Group I
Group II
Group III
Estrogen
Low
Normal
Low
FSH
Low or normal
Normal
High
Prolactin
Normal
Normal
Hypothalamus/ pituitary
No pathology
Example
Hypogonadotropic hypogonadism
Polycystic ovary syndrome (PCOS)
Gonadal failure
PRIMARY AMENORRHEA The etiologies of primary amenorrhea are multiple and diverse (Tables 16-4 and 16-5). The four most common causes of primary amenorrhea have been reported to be the following:4 (1) Gonadal dysgenesis (almost half of all cases) (2) Müllerian agenesis (i.e., congenital absence of the uterus and vagina) (3) Hypothalamic disorders, including those related to exercise and nutrition (4) Constitutional delay of puberty Other causes of primary amenorrhea, while less common, include outflow obstructions (e.g., imperforate hymen, transverse vaginal septum), androgen insensitivity syndrome, and inborn defects in gonadotropin secretion or response. Several of these are examined in this chapter; others are discussed in separate chapters.
Gonadal Dysgenesis The term gonadal dysgenesis is used globally to refer to all forms of abnormal gonads, which can occur in individuals with normal
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Chapter 16 Amenorrhea Table 16-4 Common Causes of Primary Amenorrhea Category
Frequency
Normal Secondary Sexual Development Müllerian agenesis Androgen insensitivity Constitutional delay Outlet obstruction (e.g., vaginal septum, imperforate hymen)
(~1/3 of total) 10% 9% 8% 3%
Absent Secondary Sexual Development High FSH (gonadal dysgenesis) Abnormal karyotype (e.g., 46,XO, mosaic) 46,XX 46,XY Low FSH Hypothalamic disorders Constitutional delay Hyperandrogenic conditions (e.g., PCOS, CAH) Pituitary adenomas
(~2/3 of total) 20% 15% 5% 8% 10% 6% 5%
Adapted from Practice Committee of ASRM: Current evaluation of amenorrhea. Fertil Steril 82(Suppl 1):33-S39, 2004.
karyotypes (46,XX; 46,XY) as well as a variety of abnormal or mosaic states, most commonly Turner’s syndrome (45,XO). The gonads are usually streaks of fibrous tissue. Pure Gonadal Dysgenesis
Pure gonadal dysgenesis refers to phenotypically female individuals with streak gonads and normal female external genitalia and normal müllerian structures whose karyotype can be either 46,XY (Swyer syndrome) or 46,XX. This heterogeneous condition results from a structural abnormality on the Y chromosome, a mutation in the SRY gene, or a mutation in an autosomal gene. Mixed Gonadal Dysgenesis
Mixed gonadal dysgenesis refers to individuals with defective gonadal development secondary to a chromosomal mosaic variant. Their karyotypes show partial sex chromosome monosomy with an absence or abnormality of the second sex chromosome, with 45,XO/46,XY being the most common. Their phenotypes range from phenotypic female to pseudohermaphrodite to phenotypic male, depending on the ratio of 45,XO cells to those with normal (46,XX or 46,XY) karyotypes in each gonad. These patients present with abnormal sex differentiation. There can be a streak
gonad on one side and a dysgenetic gonad or normal testicle on the other and with concurrent ipsilateral Wolffian or müllerian development. Most of these individuals have short stature, and one third will show characteristics of Turner’s syndrome. The majority of patients with gonadal dysgenesis will never have menses. This group of patients make up 40% of cases of primary amenorrhea, and 40% will have an abnormal karyotype. This abnormal karyotype will be Turner’s syndrome (46,XO) 50% of the time and a mosaicism such as XO/XY 25% of the time. Patients who present with gonadal dysgenesis and a normal karyotype need to be assessed for a variety of other conditions, such as neurosensory deafness and fragile X syndrome. These clinical associations are particularly true when familial premature ovarian failure is identified.9
General Principles of X Chromosome Genetic Disorders Short stature is the result of a mutation of the SHOX gene (short stature homeobox-containing gene). The gene is located on the pseudoautosomal region of the X chromosome, and two normal copies are required for the development of normal stature. Isolated deletions of portions of the X chromosome have also been reported. Deletions affecting Xp11 result in ovarian failure in about half of women. Deletions involving the q arm of the X chromosome also usually result in ovarian failure. Even in those who achieve normal menstruation, fertility is rare. When the deletion on the X chromosome is more distal (Xp21 region), the phenotype is generally milder. However, secondary amenorrhea or infertility is common. Most women with Xp deletions are short, regardless of their ovarian function, and present with a Turner’s syndrome-like phenotype. The molecular mechanism responsible for ovarian failure in these cases is due to loss of a putative ovarian determinant gene necessary for ovarian development, increasing follicular atresia, but not to the extent of that observed in patients with Turner’s syndrome. Translocations of the X chromosome, although extremely rare, may cause amenorrhea depending on the location of breakpoints. In a balanced X translocation one X chromosome is normal, and the other is an X autosome translocation chromosome. X inactivation is not usually random so that the normal X is usually inactivated. If the translocated chromosome were inactivated, the autosome would also be inactivated, making the
Table 16-5 Genital Tract Abnormalities Associated with Amenorrhea Asherman’s Syndrome
Müllerian Anomalies
Müllerian Agenesis
Androgen Insensitivity
Severe Hyperandrogenemia/ Insulinemia
Karyotype
46,XX
46,XX
46,XX
46,XY
46,XX
Heredity
Not hereditary
Not known
Not known
Maternal-linked recessive, 25% risk of affected child, 50% risk of carrier in women
Not known, probably multifactorial
Sexual hair
Normal female
Normal female
Normal female
Absent or sparse
Hirsutism with male pattern distribution
Testosterone
Normal female
Normal female
Normal female
Normal male range
High normal female range
Other anomalies
None
Frequent, mostly urinary
Frequent, mostly urinary
Rare
None
Gonadal neoplasia
Normal incidence
Normal incidence
Normal incidence
5% incidence of malignant tumor
Normal incidence
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Section 3 Adult Reproductive Endocrinology karyotype lethal. Nearly all males and half of the females with X autosome translocations are sterile.10 Turner’s Syndrome
It is known that specific genes in the X chromosome are essential for normal functioning of the ovaries.11 It appears that both X chromosomes with normally functioning genes need to be present in the oocytes to prevent the formation of a streak gonad. Turner’s syndrome (45,XO) is the most common cause of gonadal dysgenesis. It is usually caused by nondisjunction of the sex chromosomes and occurs in approximately 1 out of 2500 live births. In some cases, Turner’s syndrome occurs in patients with normal karyotypes (46,XX) when a genetic abnormality results in one of the X chromosomes not being fully functional. The characteristic physical features common to females with Turner’s syndrome include short stature, somatic abnormalities (webbed neck, shield chest, increased angle at the elbow known as cubitus valgus, cardiovascular abnormalities), and prepubertal status associated with elevated gonadotropins.12 Patients with Turner’s syndrome require special attention to the autoimmune disorders and renal anomalies that are frequently found with the condition. All patients with Turner’s syndrome should seek expert cardiology consultation and screening, including chest X-ray and echocardiography, at the time of diagnosis. Annual cardiac examinations, including evaluation of blood pressure, and repeated screening at 3- to 5-year intervals if the initial screening reveals no abnormalities. When the cardiac echo is abnormal or the ascending aorta cannot be visualized, magnetic resonance imaging (MRI) of the chest should be performed in all patients.12 Due to the absence of one of the X chromosomes, these patients have streak gonads with complete lack of ovarian follicle development. The absence of sex hormone production from the ovary in early adolescence results in the absence of puberty and primary amenorrhea. Patients with variations of the syndrome can present with some clinical features but not all of the characteristic physical findings. For this reason, Turner’s syndrome should be suspected in every adolescent with primary amenorrhea, sexual infantilism, and poor growth during the teenage years. If the serum FSH is elevated in such a patient, a karyotype should be obtained. Even if the FSH is normal, a karyotype should be obtained to rule out mosaicism in adolescents with poor growth after puberty (i.e., <5 feet tall). Gonadal Dysgenesis 46,XY: Swyer Syndrome
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This condition is associated with normal female phenotype and an 46,XY karyotype. These patients have normal external genitalia and normal müllerian structures with normal female testosterone levels and lack of secondary sexual development. Because the gonad is dysgenetic, antimüllerian hormone is deficient, explaining the presence of a uterus. Testosterone is low and therefore there is regression of the Wolffian ducts. About 10% to 15% of patients with Swyer syndrome possess mutations of the SRY (sex-determining region on the Y chromosome) gene located on the distal portion of Yp.13,14 Due to the significant increased risk for tumor development in patients with a Y chromosome and streak gonads, gonadectomy is recommended at an early age.
Noonan’s Syndrome
A disorder that can be confused with Turner’s syndrome is Noonan’s syndrome. In this autosomal dominant syndrome there is no chromosomal defect, but the affected individuals (both males and females) have a Turner phenotype, with webbed neck, short stature, lowset ears, and cardiac and skeletal deformities. Management of Gonadal Dysgenesis
Adolescents with gonadal dysgenesis will require hormone therapy to induce puberty and stimulate increased growth. Lowdose estrogen (0.25 to 0.3 mg/day) is used for the first year to reproduce normal pubertal development and to minimize the effect on epiphysis closure and therefore try to achieve a more acceptable final height. In some cases growth hormone is used as well to increase final adult height. After about 1 year of estrogen therapy, progesterone (medroxyprogesterone acetate, 5 mg/day, or other forms of progesterone) can be added during the last half of the month. The dose of estrogen is increased gradually so as to complete pubertal development over 2 or 3 years. The final maintenance dose is usually 2 mg of estradiol valerate or 1.25 mg conjugated estrogens daily. The estrogen can be started earlier if growth hormone is used. If not, estrogen initiation can be delayed for a short time but no later than age 14 or 15. The use of ethinyl estradiol has been shown to increase hypertensive risk in Turner’s syndrome patients. Patients with Y chromosomes will require gonadectomy to avoid the risk of developing a malignancy. Oocyte donation offers women with Turner’s syndrome the opportunity to achieve pregnancy. However, the increased cardiovascular demands of pregnancy also may pose unique and serious risk given their high rate of cardiovascular malformations (25% to 50% prevalence). A recent Practice Committee position from the American Society for Reproductive Medicine (ASRM) has stated that because the risk for aortic dissection or rupture during pregnancy may be 2% or higher, the risk of death during pregnancy is increased as much as 100-fold.12 Any significant cardiac abnormality should be regarded as a contraindication to oocyte donation. Even those having a normal evaluation should be thoroughly counseled regarding the high risk of cardiac complications during pregnancy because aortic dissection may still occur.12
Disorders of the Genital Tract Disorders of the genital tract encompass both abnormalities of the müllerian system (uterus, fallopian tubes, and vagina) and abnormalities of the external genitalia. In adolescents with normal pubertal development and primary amenorrhea, a genital tract disorder will be found on physical examination in 15% of cases. Common disorders include müllerian agenesis, imperforate hymen, and transverse vaginal septum. Müllerian Agenesis
Mullerian agenesis, also referred to as Mayer-Rokitansky-KüsterHauser syndrome, is a condition in which all or part of the uterus and vagina are absent in the presence of otherwise normal female sexual characteristics. This diagnosis accounts for approximately 10% of cases associated with primary amenorrhea.15 In Finland, the incidence was calculated to be approximately 1 of every 5000
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Chapter 16 Amenorrhea newborn girls.16 In müllerian agenesis, the ovaries are not affected and thus ovarian function is normal. Secondary sexual development and height are in a normal range. The differential diagnosis of patients who present with primary amenorrhea and have a genital tract anomaly is summarized in Table 16-4. Partial development of the müllerian structures can lead to obstructed menses and painful distention of a hematocolpos, hematometra, or hematoperitoneum. It is important to separate müllerian agenesis from complete androgen insensitivity syndrome, because the vagina may be absent or short in both disorders.17 It is currently unknown why müllerian agenesis occurs, but likely causes are mutations of genes that are responsible for müllerian tract maintenance. Thus far, no mutations have been reported.18 It appears that the mode of inheritance is not autosomal dominant.19 Approximately 30% of patients will have urinary tract anomalies, such as pelvic kidney, horseshoe kidney, unilateral renal agenesis, hydronephrosis, and ureteral duplication. Another 10% to 12% will have skeletal anomalies mostly associated with the spine. There are also reports of absent digits and webbing or fusion of fingers or toes (syndactyly). Although ultrasound could be an important aid in confirming the presence or absence of uterine structures, MRI is usually more definitive. Occasionally laparoscopic visualization is needed, because there is disagreement between MRI and laparoscopic findings.20 If persistent chronic pelvic pain and symptoms associated with endometriosis are present, laparoscopy can usually aid in determining the location and potential removal of incompletely formed müllerian structures. Outflow Obstructions
Imperforate hymen is the most frequent obstructive female genital tract anomaly, with an estimated frequency of approximately 0.1%. Imperforate hymen usually occurs sporadically, but familial cases have been reported.21 Although this entity can present in infants or children of any age as a mucocolpos, a bulging intact hymen with hematocolpos presenting at the time of menarche is not unusual. Hymenectomy effectively alleviates this problem. A transverse vaginal septum is somewhat less common than an imperforate hymen, occurring in fewer than 1 in 20,000 females. The presentation and surgical treatment is similar to an imperforate hymen if the transverse vaginal septa is located in the lower third of the vagina. However, more than 80% are located in the middle and upper vagina. Diagnosis is usually made by ultrasound or MRI. When located in these areas, septa tend to be thicker, and surgery is more difficult. Surgical management is described in detail in Chapter 51. Androgen Insensitivity Syndrome
Androgen insensitivity syndrome (formerly known as testicular feminization), is an X-linked recessive condition in which genotypic males (46,XY) develop into apparently phenotypic females who have no müllerian structures and intra-abdominal testes. The underlying cause is an abnormally functioning androgen receptor, which prevents normal masculinization. This syndrome will be identified in as many as 5% of all patients presenting with primary amenorrhea.17
In the case of complete androgen insensitivity syndrome, normal female external genitalia develop. Complete androgen insensitivity is uncommon, with a reported incidence as low as 1 in 60,000 live births. In cases of incomplete androgen insensitivity syndrome, the external genitalia can demonstrate a range of intersex abnormalities from mildly virilized female external genitalia to mildly undervirilized male external genitalia. Evaluation of Androgen Insensitivity Syndrome
These patients usually present with a family history of scant pubic hair and the presence of inguinal masses. Other female family members should be evaluated for the same diagnosis. Patients with the condition may have a eunuchoid habitus with long arms and large hands and feet. Although the breasts develop for the most part normally, they lack glandular tissue and the nipples are small with a pale areola. On pelvic examination, the patients will have scant or absent pubic hair and a blind vagina that is no more than a few centimeters long. More than 50% of patients have inguinal hernias and underdeveloped labia minora. Laboratory evaluation will demonstrate a 46,XY karyotype and elevated total testosterone (in the normal male range).22 This distinguishes patients with androgen insensitivity syndrome from those with müllerian agenesis, who will have an XX karyotype and total testosterone in the normal female range. Gonadal malignancies have been reported in the 20% range, but are rarely seen before age 20. Therefore, a typical plan of action for these patients is to wait, allowing them to reach their normal adult stature and full breast development, then perform bilateral laparoscopic gonadectomy after puberty has been reached. Patients with lack of 17β-hydroxysteroid dehydrogenase activity also have impaired testosterone production and present clinically as incomplete androgen insensitivity. The treatment for both conditions is essentially the same.
Rare Causes of Primary Amenorrhea Isolated Gonadotropin Deficiency
This disorder is characterized by a decrease or absence in endogenous gonadotropin-releasing hormone (GnRH) secretion, which results in very low to undetectable luteinizing hormone (LH) and FSH levels. Individuals with the disorder have incomplete development of secondary sexual characteristics, primary amenorrhea, eunuchoid features, and in some cases a decreased sense of smell or anosmia (Kallmann syndrome). Male patients with Kallmann syndrome have X-linked recessive idiopathic hypogonadotropic hypogonadism accompanied by anosmia caused by mutations in the KAL1 gene, localized to the pseudoautosomal region of Xp.23,24 The protein product of KAL1, anosmin, possesses neural cell adhesion molecule properties. Anosmin provides a guide for GnRH neurons and olfactory nerves to migrate from the olfactory placode across to the olfactory bulb. When anosmin is absent or defective, GnRH and olfactory neurons fail to synapse normally. The KAL1 gene escapes X inactivation and an inactive pseudogene is present on Yq. For individuals with anosmia or hyposmia, there is evidence of hypoplasia of the olfactory bulbs on MRI. No KAL1 gene mutations have been identified in females with idiopathic hypogonadotropic hypogonadism and
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Section 3 Adult Reproductive Endocrinology
Abnormalities of GnRH receptors have also been identified. The phenotype of GnRH resistance ranges from complete idiopathic hypogonadotropic hypogonadism to oligo-ovulation. Baseline levels of LH and FSH may be in the prepubertal or normal range. However, levels of other pituitary hormones, such as thyrotropin, growth hormone, prolactin, and corticotropin, are normal. Due to the failure to increase gonadal sex steroid secretion during puberty, secondary sex characteristics fail to develop and closure of the epiphyseal plates of the long bones is delayed, resulting in a eunuchoid habitus in which the arm span is greater than the height. Even in patients with complete forms, pulsatile GnRH administration may increase pituitary gonadotropin response; pregnancies have been reported.27
family should be questioned about familial disorders such as diabetes mellitus, previous medical disorders that may have been treated with gonadotoxic agents, and surgical disorders that involve the genital tract, including abnormal sexual differentiation. The functional inquiry should include secondary sexual development, galactorrhea, and the presence of hyperandrogenic symptoms. A detailed physical examination includes gynecologic examination, body mass index, pubertal status, signs of hyperandrogenism or other skin manifestations of endocrine disorders, and genital tract evaluation. Milestones of sexual development and growth should be documented. The most important single feature on history and physical examination is the presence or absence of breast development, which is a clear indication of the initiation of puberty. The presence of galactorrhea either described by the patient or observed by a careful breast examination is of great clinical significance. Specific clinical features of the galactorrhea, such as whether it is unilateral or bilateral, constant or intermittent, will determine the potential endocrine nature of the symptom. Galactorrhea of hormonal origin comes from multiple duct openings on the breast. This is in contrast to secretions occurring from a single duct, which are usually related to a local problem. Gynecologic examination will usually reveal the presence of any genital abnormities, including obstructive processes.
Treatment
Imaging
Treatment of isolated gonadotropin deficiency and receptor abnormalities will require low-dose estrogen (0.25 to 0.3 mg/day) to induce progressive pubertal maturation in a manner similar to Turner’s syndrome. Patients should be monitored at 2- or 3-month intervals to determine the rate of skeletal growth and development. After the first year, the addition of a progestin (medroxyprogesterone acetate, 5 mg/day) can be added for the last half of the month to induce menses and protect the endometrium from cancer. Once sexual maturation is completed, patients can be maintained on cyclic hormones or oral contraceptives.
In patients with primary amenorrhea, physical examination will often detect genital tract anomalies. However, the characterization of the specific anomaly often requires imaging studies. In some cases, abdominal ultrasonography is adequate to determine the presence or absence of a uterus. Probably the most effective imaging method for characterizing congenital anomalies is MRI of the pelvis. Congenital anomalies are considered in depth in Chapters 12 and 51. In patients without secondary sexual development, radiographic determination of bone age should be obtained. In patients with elevated prolactin, an MRI of the pituitary is required.
anosmia, suggesting that other autosomal genes may be involved.25 LH Receptor Abnormalities
Abnormalities of the LH receptor in 46,XX females will result in normal female sexual development and primary amenorrhea.26 Serum LH may be normal to increased, FSH is normal, follicular phase estradiol levels are normal, and progesterone is low. The uterus is small and the ovaries are consistent with anovulation. Gonadotropin-Releasing Hormone Receptor Abnormalities
Diagnostic Approach for Primary Amenorrhea What Age?
An evaluation of primary amenorrhea is indicated when an adolescent fails to menstruate by age 15 in the presence of normal secondary sexual development (two standard deviations above the mean of 13 years), or within 5 years after breast development, if that occurred before age 10.2 This age has recently been adjusted to a younger age, because girls are menstruating at a younger age. If there is a failure to initiate breast development by age 13 (two standard deviations above the mean of 10 years), an investigation should also be initiated.2 These criteria are not absolute, and complete evaluation should be initiated if the patient presents with amenorrhea and obvious associated pathology such as cyclic pain or a blind vaginal pouch. History and Physical Examination
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A careful history is a key component to the evaluation and planning for the treatment of amenorrhea (Fig. 16-1). Special emphasis should be focused on physical or emotional stress, nutritional status, and history of genetic inherited disorders. The
Laboratory Evaluation
Patients with primary amenorrhea should have an initial set of laboratory studies, which will often determine the next series of diagnostic or therapeutic management steps. Patients with normal secondary sexual development should have a pregnancy test in most cases. For patients without signs of secondary sexual development, a karyotype should be performed. For all patients regardless of sexual development, the investigation starts with measurement of serum FSH, thyrotropin, and prolactin. The estimation of thyrotropin is still indicated to evaluate for subclinical hypothyroidism, even in the absence of overt thyroid disease. However, only severe forms of hypothyroidism lead to amenorrhea, and an evaluation of the thyroid would probably be performed before amenorrhea occurs. If hirsutism is present or if androgen insensitivity syndrome is suspected, androgens should be evaluated. Total testosterone will be elevated in this syndrome as well as in cases of ovarian tumors. Dehydroepiandrosterone sulfate (DHEAS) will be elevated in patients with adrenal tumors and Cushing’s disease. Borderline elevation of these androgens is often seen with
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Chapter 16 Amenorrhea History Physical examination
Absent secondary sexual development
Normal secondary sexual development
Normal Gynecological Examination
Normal
Hirsutism Acne
Laboratory Evaluation Gynecological Examination Abnormal Beta-hCG
FSH
Prolactin
TSH
Imaging Studies Positive
High
Pregnancy Midline mass
Hypothyroidism
Testosterone DHEAS 17-hydroxyprogesterone
High Pituitary Adenoma
Absent Uterus
High TSH, PRL,FSH Normal; Beta-hCG negative
High Gonadal Dysgenesis
Karyotype Low or normal
Testosterone 46,XY ↑ testosterone
Outflow Obstruction Figure 16-1
Androgen Insensitivity
Constitutional Delay
Mullerian Agenesis
Excercise induced, stress, weight loss
PCOS or Other Hyperandrogenic Condition
Hypothalamic Dysfunction
Flow diagram in the evaluation of adolescents with primary amenorrhea, showing major decision points.
polycycstic ovary syndrome. 17-hydroxyprogesterone is often elevated in patients with adult onset congenital adrenal hyperplasia, although a provocative test is often necessary in subtle cases.
(e.g., hyperprolactinemia), and (4) premature ovarian failure (Table 16-6).
Hypothalamic Amenorrhea
SECONDARY AMENORRHEA
Regulation of GnRH Secretion
Secondary amenorrhea is a condition in which menstruation begins at the appropriate age but later stops for reasons not due to pregnancy, lactation, or menopause. For clinical purposes, the length of amenorrhea should be equal to at least 3 of the previous cycle intervals, or 6 months, although patients with oligomenorrhea (menstruation <9 times per year or bleeding intervals >40 days) often have similar underlying pathology. This condition affects at least 4% of women and is more common in those whose weight is below or above the normal range. The four most common causes of secondary amenorrhea are (1) hypothalamic amenorrhea (e.g., exercise induced), (2) hyperandrogenic states (e.g., PCOS), (3) pituitary disorders
The secretion of LH and FSH from the pituitary is regulated by pulsatile secretion of GnRH from the hypothalamus. Small alterations in GnRH pulsatile frequency and/or amplitude can result in a range from subtle luteal phase defects to anovulation and amenorrhea. The neurohormone GnRH is produced in specific neurons localized in the preoptic area of the hypothalamus. GnRH is secreted in a pulsatile manner into the portal bloodstream at the level of the median eminence. It travels to the anterior pituitary, where it stimulates gonadotrophs to secrete LH and FSH via membrane receptors. GnRH is degradated by proteolysis within a few minutes. It is not possible to directly assess GnRH secretion, because this
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Section 3 Adult Reproductive Endocrinology Table 16-6 Common Causes of Secondary Amenorrhea Categories with Examples
Approximate Frequency
Hypothalamic origin Weight loss/anorexia Postcontraception contraceptives
34%
Hyperandrogenic states PCOS Ovarian/adrenal tumors Adult-onset congenital adrenal hyperplasia
30%
Pituitary disorders (hyperprolactinemia)
14%
Premature ovarian failure 46,XX Abnormal karyotype
12%
Uterine pathology Asherman’s syndrome Cervical stenosis
7%
Systemic disease Hypothyroidism Cushing’s syndrome
3%
From Herman-Giddens ME, Slora EJ, Wasserman RC, et al: Secondary sexual characteristics and menses in young girls seen in office practice: A study from the Pediatric Research in Office Settings network. Pediatr 99:505-512, 1997; and Reindollar RH, Novak M, Tho SP, McDonough PG: Adult-onset amenorrhea: A study of 262 patients. Am J Obstet Gynecol 155:531–543, 1986.
decapeptide is rapidly metabolized within 2 to 4 minutes in the peripheral circulation. Clinical investigation relies on measurement of LH concentrations as the surrogate marker for hypothalamic GnRH secretion. In women with regular menstrual cycles, clinical studies have demonstrated a characteristic pulsatile secretion of LH at a frequency of 90 to 120 minutes during the follicular phase and a frequency of 180 to 240 minutes during the luteal phase. Gonadotropin-releasing hormone secretion is modulated by many other endocrine and neuronal systems. Some of the most important neurotransmitter agents that regulate GnRH secretion are dopamine, norepinephrine, and serotonin. Activation of the noradrenergic system is associated with increased GnRH release, whereas dopaminergic or serotonergic activation inhibit GnRH release. These observations explain the disruption of normal menstrual cycles in patients who take dopamine receptor antagonists (e.g., phenothiazine), stimulants, antidepressants, and sedatives. Two amino acids, glutamate and aspartate, have been implicated in a regulatory role for GnRH secretion, primarily during pubertal maturation. These two amino acids have been shown to be localized to the arcuate nucleus in the media basal hypothalamus adjacent to GnRH neurons and appear to activate GnRH secretion during puberty in monkeys. Endogenous opiate peptides (e.g., endorphins, enkephalin, and dynorphin) appear to play an inhibitory role in GnRH secretion. In patients with hypothalamic amenorrhea, blockade of opiate receptors with antagonists (e.g., naloxone or naltrexone) induces an increase in pulsatile release of GnRH and LH. Long-term treatment of hypothalamic amenorrhea patients with naltrexone can result in return of normal menstrual cycles in some individuals.
that there is a slowing of the GnRH pulse generator, as reflected by a decrease in peripheral pulsatile LH secretion in these women. The pattern of LH secretion may vary. During the early onset, LH pulse frequency and amplitude may be normal. In more severe cases, regression to a pubertal pattern with sleepassociated increases may be observed. The pituitary gland is fully capable of synthesis and release of LH and FSH. However, responses to exogenous GnRH in these individuals may vary depending on the endogenous GnRH priming of the pituitary gland. LH and FSH responses to exogenous GnRH may be absent, normal, or supranormal. In these patients, after a period of priming with intravenous pulsatile GnRH (1 to 2 mg/90 minutes), normal levels of LH and FSH can be restored and responses to exogenous GnRH become normal. Taken together, these observations suggest that endogenous GnRH secretion is deficient and gonadotropin secretion and ovarian function can be normalized with physiologic replacement of exogenous, pulsatile GnRH. Primary Hypothalamic Amenorrhea
Primary hypothalamic amenorrhea is a diagnosis of exclusion when no specific cause of amenorrhea has been found. Patients with hypothalamic amenorrhea unrelated to stress will usually have normal prolactin and thyrotropin levels with a low or normal serum FSH level. Patients with hypothalamic amenorrhea also have decreased pulsatile frequency and amplitude for LH, which is believed to be a direct reflection of changes in GnRH pulses. Stress-Related Amenorrhea
Exposure to chronic stress often disrupts reproductive function. Chronic environmental stressors lead to long-term activation of the hypothalamic-pituitary-adrenal (HPA) axis, which in turn induces ovulatory dysfunction at either the hypothalamic or the pituitary level. An acute stress response is much less likely to alter ovulatory function. The stress response associated with chronic stress involves activation of the HPA axis and increased secretion of a “stress response complex” of hormones such as corticotropin-releasing hormone (CRH), corticotropin, cortisol, prolactin, oxytocin, vasopressin, norepinephrine, and epinephrine (Table 16-7). These hormonal effects impact on reproductive function at several levels. For example, CRH has been shown to directly inhibit GnRH secretion in rats, monkeys, and humans at the hypothalamic level in vitro and in vivo. This inhibition can be negated by administration of a CRH receptor antagonist or by naloxone. Taken together, these observations suggest that the inhibitory effect of CRH is mediated in part by increased secretion of endogenous opioids. The increased secretion of corticotropin at Table 16-7 Associated Neuroendocrine Abnormalities in Hypothalamic Amenorrhea Increased daytime cortisol secretion Increased amplitude and duration of nocturnal melatonin secretion
Hypothalamic Dysfunction and Amenorrhea
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The basic defect in women with hypothalamic amenorrhea is the failure of the hypothalamus to increase GnRH output in the presence of severe hypoestrogenism. Most investigators believe
Increased nocturnal secretion of GH Elevated CRH levels in cerebrospinal fluid Blunted elevation of prolactin, corticotropin, and cortisol during the noon meal
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Chapter 16 Amenorrhea the pituitary level may also suppress pituitary response to GnRH. In addition, increased cortisol levels may also dampen pituitary response to GnRH. Exercise-Induced Hypothalamic Amenorrhea
Menstrual cycle disturbances are common among competitive athletes, including ballet dancers, marathon runners, gymnasts, and figure skaters.28 Depending on the type of activity and competition level, the incidence of amenorrhea varies from 5% to 25%. The incidence of menstrual irregularities appears to be greatest in activities that favor a low body weight, such as ballet (6% to 43%) and middle and long distance running (24% to 26%). The incidence appears to be less frequent in bicycling (12%) and swimming (12%). In athletes with menstrual irregularities, LH pulsatility is altered and can range from a decreased frequency to a transitional pattern. It is well known that acute exercise leads to hyperactivation of the HPA axis. However, LH pulsatility is not disrupted by the stress of exercise but rather because of reduced energy availability. The role of leptin in these circumstances is similar to its role in other energy deprivation states. Many of these athletes have the “female athlete triad” of amenorrhea, osteoporosis, and eating disorders. Bulimia and Anorexia Nervosa
Severe eating disorders such as bulimia and anorexia nervosa disrupt menstrual function. Bulimia is characterized by alternating episodes of consumption of large amounts of food over a short time (binge eating) followed by periods of self-induced vomiting, excessive use of laxatives or diuretics, and food restriction. The incidence of bulimia is estimated to be 4.5% to 18% percent among high school and college students. Bulimia usually begins between ages 17 and 25. Anorexia nervosa is a severe eating disorder characterized by extreme weight loss (>25% of ideal body weight), body image disturbances, and an intense fear of becoming overweight and refusal to take action to increase the weight. The overall incidence of anorexia ranges from 0.64 per 100,000 to 1.12 per 100,000. It is extremely important for the clinician to recognize early signs of these disorders so that appropriate intervention and treatment can be obtained. The mortality associated with anorexia is as high as 9%, usually secondary to cardiac arrhythmia precipitated by electrolyte abnormalities and diminished heart muscle mass. Suicide is also more common. The clinical features of bulimia and anorexia are listed in Tables 16-8 and 16-9.
Table 16-8 Common Features of Bulimia
Anorexia nervosa is associated with multiple neuroendocrine abnormalities (Table 16-10). As a result of decreased caloric intake, thyroxine (T4) conversion to triiodothyronine (T3) is decreased, resulting in lowered basal metabolism. As a result, thyroxine is converted to an inactive isoform, reverse triiodothyronine (reverse T3). Profound hypothalamic dysfunction is manifest by hypothermia and impaired secretion of vasopressin that can result in partial diabetes insipidus with the inability to concentrate urine. Hyperactivation of the HPA axis results in hypersecretion of cortisol, but manifestations of hypercortisolism are rarely present due to number of decreased cellular glucocorticoid receptors. These patients also have increased central opioid activity. Bulimia and anorexia result in a prepubertal pattern of LH similar to patients with functional hypothalamic amenorrhea secretion, presumably due to a marked decrease in GnRH secretion. With weight gain, patients with anorexia will resume Table 16-9 Common Features of Anorexia Nervosa Preoccupation with handling of food Bulimic behavior Calorie counting Distortion of body self-image Hyperactivity Obsessive-compulsive personality Increased incidence of past sexual abuse Amenorrhea Constipation Coarse, dry skin Soft, lanugo-type hair Hypothermia with defective thermoregulation Mild bradycardia Cardiac arrhythmias Hypotension Hypokalemia secondary to diuretic or laxative abuse Osteopenia Increased serum beta-carotene levels Anemia, leukopenia Elevated hepatic enzymes
Table 16-10 Neuroendocrine Abnormalities Associated with Anorexia Nervosa Diminished GnRH LH pulsatile frequency and amplitude Low blood LH and FSH levels Impaired corticotropin response to CRH stimulation testing
Irregular menstrual cycles
Resistance to dexamethasone suppression
Dental enamel erosion
Increased corticotropin levels
Enlargement of salivary glands
Increased 24-hour urinary free cortisol levels
Acute irritation of esophageal mucosa
Normal prolactin level
Esophageal or gastric rupture
Normal TSH levels with high reverse T3 and low T3 levels
Hypokalemia
Elevated GH levels
Aspiration pneumonia
Decreased IGF-I levels
Ipecac poisoning
Diabetes insipidus
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Section 3 Adult Reproductive Endocrinology normal patterns of LH secretion and may have normal or supranormal responses to GnRH. Despite return to normal body weight, up to 50% remain anovulatory. As in all energy deprivation states, leptin plays a critical role in the disruption of the hypothalamic function that results in amenorrhea. Leptin is a protein hormone secreted by adipose tissue and has an important role in adaptation to starvation. Leptin-deficient ob/ob mice and leptin-resistant db/db mice show obesity and hypogonadotropic hypogonadism. However, the principal role of leptin is in caloric deprivation; it acts as the signal from the periphery to the brain about energy deficit. This energy deficit is signaled to the hypothalamicpituitary axis through decreased leptin levels. Leptin may have a role in the other neuroendocrine abnormalities such as thyroid and insulin-like growth factor-I (IGF-I) seen in anorexics and in other energy-deficient states such as excessive exercise.29 Evaluation of Hypothalamic Amenorrhea
Because this is a diagnosis of exclusion, significant organic diseases must be excluded (see Table 16-2). A detailed interview may identify a stressful event or emotional crisis (divorce, relationship breakup, death of a friend or relative) preceding the amenorrhea. Other interpersonal and environmental stressors may also be present, such as academic pressures, job stresses, or psychosexual problems. A careful review of the patient’s current lifestyle, including exercise intensity, dietary choices, and the use of sedatives or hypnotics, may be helpful in characterizing the psychogenic stress components.30 Patients with hypothalamic amenorrhea will have a history of normal menarche and regular menstrual cycles between 26 and 35 days in length. These women typically are intelligent, highachievers who are usually thin or of normal body weight. The physical examination should focus on identifying galactorrhea, thyroid dysfunction, and evidence of hyperandrogenemia (i.e., acne, hirsutism). Oral examination may identify the peculiar dentition or enlarged salivary glands of a bulimic patient. The pelvic examination should be normal except for a thinned vaginal mucosa or absent cervical mucus, which are characteristics of hypoestrogenism. Despite these findings, these patients do not usually experience hot flushes. Laboratory evaluation should include measurement of serum LH, FSH, prolactin, thyrotropin, and estradiol. LH and FSH can be either low or normal, and estradiol levels will be either low or within the lower limits of normal. Most of the other pituitary hormones should be in the normal range. In many patients, the progestin challenge test (medroxyprogesterone acetate 10 mg for 7 days) will not result in uterine bleeding. This test is a bioassay for the absence of estrogen priming of the endometrium and reflects the low circulating levels of estradiol. Clinical Management of Hypothalamic Amenorrhea
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The first step in clinical management is to identify and treat environmental stressors. Appropriate support and counseling often helps patients develop coping mechanisms that allow them to live healthier lifestyles. In patients with eating disorders and in many athletes, dietary consultation is extremely helpful. After lifestyle modification, spontaneous recovery of menstrual function will occur in 70% to 80% of patients. For patients
who continue to have oligomenorrhea, periodic evaluation of menstrual status every 4 to 6 months is prudent. The primary medical concerns for these patients are infertility and bone loss. Athletes have been characterized as having the “female athlete triad” of amenorrhea, osteoporosis, and eating disorders. Management of these patients should emphasize measurement of bone density, dietary and psychological counseling, weight change, and calcium intake. One goal of therapy may be to decrease the level of exercise, improve the diet, and achieve weight gain. For others, exercise may not induce amenorrhea but may be associated with longer menstrual cycles, luteal phase defects, and intermenstrual spotting. These reproductive defects may be reversible with a decrease in exercise level or intensity. Infertility
In patients who desire fertility but fail to resume normal cycles, ovulation induction is indicated. Clomiphene citrate (25 to 50 mg for 5 days) can be attempted, but this approach will rarely induce ovulation in patients with hypothalamic amenorrhea. In contrast, human menopausal gonadotropin is usually highly successful for inducing ovulation. These patients are generally exquisitely sensitive to human menopausal gonadotropins, and thus treatment should be started at the lowest dose. Some centers use a modified insulin pump to administer intravenous pulsatile GnRH at a dose of 5 μg every 90 minutes. This approach will successfully induce ovulation after a 13- to 14-day treatment period. Pump therapy is associated with ovulation rates of greater than 90%, with generation of a single dominant ovarian follicle in most cases, and lower rates of ovarian hyperstimulation. After ovulation, the corpus luteum should be supported with either GnRH or human chorionic gonadotropin (1500 units intramuscularly or 2500 units subcutaneously) every 3 days for four doses. Supplemental progesterone can also be used. Bone Loss
The greatest long-term health risk is bone loss that can put the patient at risk for osteoporosis, particularly later in life. In athletes with hypothalamic amenorrhea, the type of exercise activity significantly affects the overall osteogenesis. In young women with persistent hypoestrogenism, the bone mass can decrease at a rate of 2% to 5% per year for the first 3 to 5 years. The primary cause of bone loss in these patients is hypoestrogenemia, and thus patients not desiring fertility will benefit from hormone replacement therapy. Bone loss is most sensitive to estrogen.31,32 Although several forms of hormone replacement have been described, placing young women on oral contraceptives has been the treatment of choice. Although many women prefer to have menses in association with hormone replacement, athletes who find this to be inconvenient can be safely kept on continuous hormone replacement or birth control pills. Periodic measurements of mineral bone density are worthwhile to monitor the progress of patients both from a dietary and hormone replacement point of view. Dual energy X-ray absorptiometry (DEXA) is often helpful in convincing patients to begin estrogen therapy. The use of bisphosphonates in women of reproductive age should be carefully considered, given their accumulation in bone and unknown effects on a fetus in cases where fertility is being sought.
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Chapter 16 Amenorrhea Treatment of Anorexia Nervosa
Therapeutic approaches to anorexia nervosa include behavior modification, group therapy, and individual psychotherapy. Generally, a team approach consisting of a psychiatrist and a general medicine specialist with expertise in eating disorders is desirable. Because of the high mortality rate and the significant morbidity associated with anorexia, it is important to obtain psychiatric consultation and follow-up in all patients with eating disorders. The long-term success rates for treatment of anorexia nervosa and bulimia remain low. Postcontraception Amenorrhea
Amenorrhea after long-term contraception use remains a concern, but the issues of concern have changed. In the past, use of highdose (>50 μg ethinyl estradiol) oral contraceptives was associated with prolonged amenorrhea after discontinuation. With modern low-dose oral contraceptives, amenorrhea is uncommon, but reversible cycle disturbances after discontinuing oral contraceptives can last up to 9 months or longer.33 Fortunately, oral contraceptives do not affect fertility in the long term. Amenorrhea that continues more than 2 months after discontinuation of an oral contraceptive should trigger an investigation for other causes of amenorrhea. A more common problem has become amenorrhea after the intramuscular use of medroxyprogesterone acetate (Depo-Provera) for contraception. Amenorrhea is common after discontinuation of this type of contraception, and the return to baseline fertility takes an average 10 months.34 For this reason, investigation for amenorrhea after discontinuation of depot medroxyprogesterone should be limited until 12 months after the last injection.
Hyperandrogenic States Polycystic Ovary Syndrome
Polycystic ovary syndrome (PCOS) is one of the most common causes of ovulation dysfunction (see Chapter 19). Although this complex syndrome has a wide range of clinical manifestations, amenorrhea was one of the primary manifestations first described by Stein and Leventhal in 1935 along with infertility and enlarged ovaries.35 Contemporary series suggest that only about 25% of patients with PCOS will have amenorrhea.36 The pathology, diagnosis, and treatment of PCOS is discussed in depth in Chapter 15. Other Hyperandrogenic States
Other hypoandrogenic states that mimic PCOS can also result in amenorrhea. Probably the most serious of these conditions are ovarian and adrenal tumors. Likewise, Cushing’s syndrome can cause amenorrhea secondary to increased androgens. Another cause is adult-onset congenital adrenal hyperplasia. The basis of the workup to exclude these conditions includes measurement of serum androgens, including total testosterone, DHEAS, and 17-hydroxyprogesterone. Imaging of the ovaries and, in some cases, adrenal glands is also important. This details of this evaluation are given in Chapter 18.
Disorders of the Anterior Pituitary Pituitary tumors commonly interfere with normal reproduction. Small pituitary tumors can present clinically as irregular or
absent menses or galactorrhea. Less commonly, large pituitary tumors manifest as headaches and compression of the optic chiasm and bitemporal hemianopsia related to their growth in a confined anatomic space. The most common pituitary tumor is the prolactin-secreting adenoma, which accounts for almost 70% of all pituitary adenomas. The second most commonly encountered pituitary tumor is a nonfunctioning pituitary adenoma, which constitutes at least 25% of all pituitary tumors. Less common pituitary tumors secrete growth hormone, corticotropin, thyrotropin, FSH, or LH. These tumors increase prolactin levels by compressing the pituitary stalk and interfering with the release of dopamine, which acts as a prolactin inhibiting factor. Amenorrhea results in addition to diseases caused by other pituitary tumors, including acromegaly (growth hormone-secreting tumors), Cushing’s disease (corticotropin-secreting tumors), or hyperthyroidism (thyrotropin-secreting tumors). Diagnosis and management of these tumors is discussed in depth in Chapter 22. Prolactin-Secreting Adenomas
Prolactin-secreting adenomas are the most common pituitary tumors, accounting for half of all pituitary adenomas found at autopsy. Classification has been attempted by a variety of different histologic findings; however, the most useful form of classification is according to function. Hyperprolactinemia is associated with decreased estradiol concentrations as well as amenorrhea or oligomenorrhea. In women with hyperprolactinemia, the prevalence of pituitary tumor is 50% to 60%,37 and the likelihood of a pituitary tumor is unrelated to the level of prolactin found.37 The poor correlation between tumor size and serum prolactin indicates that MRI or computed tomography (CT) scanning of the pituitary should be performed whenever serum prolactin levels are consistently elevated.38 Although the exact incidence of these tumors is unknown, autopsy series have shown the presence of microadenomas to range from 9% to 27%.39,40 The distribution of these types of tumors appears equal among gender. Empty Sella Syndrome
This syndrome refers to a congenital incompleteness of the diaphragm of the sella turcica, allowing for extension of the subarachnoid space into the pituitary fossa. This can also occur secondary to surgery, radiation therapy, or infarction of a pituitary tumor. This anatomic abnormality is found in approximately 5% of autopsies, with a high predominance in women. Empty sella is found in 4% to 16% of patients with amenorrhea-galactorrhea.41 Galactorrhea and elevated serum prolactin levels can be seen. Annual surveillance with serum prolactin levels is sufficient since they rarely develop prolactinomas. The purpose of treatment is alleviation of symptoms. Postpartum Pituitary Necrosis (Sheehan’s Syndrome)
Postpartum pituitary necrosis is usually preceded by a history of severe obstetrical hemorrhage with hypotension, circulatory collapse, and shock.42 After fluid resuscitation of the patient, this condition may be manifested by clinical evidence of partial or panhypopituitarism. Simmonds was the first to describe this clinical syndrome although the most complete description has been attributed to Sheehan. This condition constitutes an endocrine emergency that can be life-threatening.
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Section 3 Adult Reproductive Endocrinology The pathophysiology of this process is not entirely clear. With pregnancy, there is an increase in blood supply to the pituitary bed and the pituitary gland enlarges. During the period of profound hypotension, Sheehan postulated that occlusive spasm of the arteries that supply the pituitary and stalk occurs. This leads to venous stasis and thrombosis of the pituitary portal vessels, causing a variable degree of pituitary ischemia and cell death. Many patients initially present with a failure to have breast engorgement and lactation due to a deficiency in prolactin secretion. These women may also have other anterior pituitary deficiencies. The posterior pituitary is usually spared because it is less dependent on the portal blood supply. In some patients, the absence of corticotropin secretion leads to inadequate cortisol secretion, resulting in postural hypotension, nausea, vomiting, and lethargy. Hypothyroidism may be noted later in this syndrome. Recovery of pituitary function has been reported in a few cases. Post-traumatic Hypopituitarism
This condition can arise after severe head trauma as a result of a sudden deceleration of the head and occult damage to the pituitary stalk or hypothalamus during a motor vehicle accident. Trauma may also be associated with a basal skull fracture or an episode of unconsciousness. These individuals will often manifest a delay from injury to presentation and may display evidence of partial hypopituitarism or panhypopituitarism. These symptoms can include amenorrhea, galactorrhea, hypogonadism, loss of axillary and pubic hair, anorexia, and weight loss. In these patients, evaluation of adrenal function is most critical because adrenal failure is life-threatening. The diagnostic evaluation and management is similar to that described for Sheehan’s syndrome. Pituitary Apoplexy
This medical emergency is characterized by an acute infarction of the pituitary gland. Patients will complain of a sudden onset of a severe retro-orbital headache and visual disturbances that may be accompanied by lethargy or loss of consciousness. These symptoms may mimic other neurologic emergencies such as hypertensive encephalopathy, cavernous sinus thrombosis, ruptured aneurysm, or basilar artery occlusion. CT or MRI may indicate hemorrhagic changes in the pituitary sella region. Patients with pituitary tumors are at higher risk for this complication. For some patients, neurosurgical consultation and emergency decompression may become necessary. Provocative testing as described for Sheehan’s syndrome should be performed to evaluate for multiple pituitary deficits. Appropriate replacement of target tissue hormones should be instituted based on testing. Postirradiation Hypopituitarism
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Exposure to therapeutic radiation sources for treatment of midline tumors of the central nervous system can place patients at increased risk for delayed development of hypopituitarism. In general, sensitivity to radiation is greatest for gonadotrophs, followed by corticotrophs and thyrotrophs. The onset of pituitary deficiencies may be insidious but can occur within 1 year of radiotherapy. Periodic assessment of hypothalamic-pituitary function should be performed for an indefinite period of time, and appropriate replacement hormone therapy should be instituted as these deficiencies develop.
Evaluation of Pituitary Adenomas
The clinical manifestations of these adenomas are usually more obvious in women, due to the disruption of menses. The most common symptoms of a prolactin-secreting adenoma in women are galactorrhea, irregular periods, headaches, and infertility. Men can experience hypogonadism due to these tumors, but the tumors are usually large and produce high serum prolactin levels. Approximately one third of women with amenorrhea will have elevated prolactin levels; one third of women with galactorrhea and elevated prolactin levels will have normal menses and one third of women will have a high prolactin level without galactorrhea.43 As many as a third of patients with secondary amenorrhea will have a prolactinoma and when associated with galactorrhea, half of the patients will have normal findings on imaging of the sella turcica.43,44 The apparent clinical difficulty in associating clinical symptoms, laboratory values, and sella turcica imaging is the fact that there is tremendous variability in the detection of prolactin in clinical assays. The immunoreactivity of clinical assays usually detects the small form of prolactin, which also has more biologic activity. Big forms of prolactin can also be secreted by pituitary adenomas and, since this prolactin type cannot usually be detected by the immunoassays, the diagnosis of a pituitary adenoma may be missed. Therefore, whenever the clinical scenario of galactorrhea is present, particularly in a patient with irregular menstruation, imaging of the pituitary gland must be considered and clinical intervention should be instituted.45,46 Some patients with high serum prolactin levels can also have what is referred to as a “high-dose hook effect” where large amounts of prolactin prevent accurate assessment by the immunoassay. Dilutions of serum samples are able to detect the abnormality.47 The mechanism by which prolactin causes oligomenorrhea and amenorrhea is due to the inhibition of pulsatile secretion of GnRH by elevated prolactin.48,49 The measurement of thyrotropin should be included as part of the evaluation. Although prolactin levels associated with hypothyroidism are generally less than 100 ng/mL, these levels can induce galactorrhea. Hyperprolactinemia in hypothyroidism is the result of increased thyrotropin-releasing hormone (TRH) stimulation of the pituitary gland. TRH is a potent stimulant of prolactin-secreting cells. The extent of pituitary deficiencies can be characterized by provocative testing with combined intravenous injection of the hypothalamic releasing factors GnRH, TRH, growth hormone releasing hormone, and CRH.50 Management of Pituitary Adenomas
The use of dopamine agonists such as bromocriptine lowers the circulating levels of prolactin and restores the normal response of the ovary to gonadotropins and restores normal menstrual function. The treatment with bromocriptine, a dopamine agonist, inhibits pituitary prolactin secretion. This medication is associated with many side effects; 10% of patients cannot tolerate the medication and will discontinue it. Most patients complain of nausea, headache, and faintness, usually due to orthostatic hypotension. Other side effects include dizziness, fatigue, nasal congestion, vomiting, and abdominal cramps, which can be diminshed by starting the patient on a low dose of the medication and slowly increasing it. Some patients can benefit from vaginal administration of bromocriptine to avoid the
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Chapter 16 Amenorrhea gastrointestinal side effects.51 Vaginal administration is effective largely by avoiding the first pass through the liver. There is no evidence that bromocriptine harms the fetus. However, most clinicians recommend discontinuing the medication during pregnancy.52 More than 80% of patients with amenorrhea and galactorrhea in association with hyperprolactinemia will have their menses restored 5 to 7 weeks after therapy is started.53 The cessation of galactorrhea is much slower than the restoration of menses, and complete cessation of galactorrhea occurs in half of patients after 4 months of use. Up to 75% of patients who stop the treatment will develop symptoms again.54 It is possible for macroadenomas to regress with bromocriptine treatment, but it requires higher doses and a longer period of use. Most patients have a rapid shrinkage in the first 3 months of therapy followed by a slower reduction.55 Patients who initially present with serum prolactin levels over 1000 ng/mL have tumors that invade into their cavernous sinuses. These individuals usually have inoperable tumors and require long-term suppression with dopamine agonists. Bromocriptine can also be used for patients who have failed surgery and radiation therapy. Cabergoline is an alternative to bromocriptine. Side effects seem to develop less frequently and the medication is taken once or twice weekly. Due to a limited experience on fetal safety, this agent should be used with caution in patients who are trying to conceive.56-58 Transsphenoidal surgery has also been used to treat pituitary adenomas. Symptom resolution is achieved in 30% of patients with macroadenomas and 70% of patients with microadenomas; this is highly dependent on the experience of the neurosurgeon.59 Tumor recurrence is high, especially after surgery for macroadenoma. Potential postoperative complications include panhypopituitarism, meningitis, cerebrospinal fluid leaks, and diabetes insipidus. The high success rate of medical therapy, recurrence of disease, and potential complications of surgery have limited the use of surgical intervention to patients who have failed medical therapy. Radiation therapy is less satisfactory than surgery for the treatment of pituitary adenomas, and the response is very slow. Under specific circumstances radiation can be delivered with a gamma knife procedure. Patients who respond to treatment of hyperprolactinemia can breast-feed if desired and usually can experience normal lactation without fear of tumor growth. There is only a small chance of growth of most pituitary tumors during pregnancy. Up to 5% of patients will have tumor enlargement, which is usually asymptomatic; less than 2% will develop symptoms.60 Most symptomatic patients present with headaches, which usually precede any visual abnormalities. During pregnancy there is normal pituitary growth, typically due to the increased size of the prolactin-secreting cells. Insufficient blood supply to the adenoma may cause this infarct. Occasionally patients may have restoration of normal menses from tumor infarction in pregnancy or postpartum. Surveillance during pregnancy with monthly visual field examinations or serum prolactin measurements has not been clinically useful. Patients who become symptomatic should be assessed and treated. Most patients will respond to bromocriptine, and it is very uncommon to require termination of pregnancy or neurosurgery.61 Dopamine agonists used during pregnancy do not affect decidual secretion of prolactin, which is under control of estrogen and progesterone rather than dopamine.
Cushing’s Disease and Acromegaly
Although amenorrhea and/or galactorrhea are usually encountered with pituitary prolactinomas, these symptoms may also precede corticotropin- or growth hormone-secreting tumors. If the patient presents clinical symptoms of glucocorticoid excess suggestive of Cushing’s disease, a corticotropin serum level and a 24-hour urine collection for free cortisol should be ordered. Excessive production of growth hormone can rarely occur in children and is referred to as gigantism. In adults excessive production of growth hormone from a pituitary tumor is called acromegaly. After the final height is achieved, the excessive growth of this syndrome is restricted to the acral areas, such as hands, feet, and facial features. Excessive sweating and fatigue are common. If the patient presents with signs and symptoms of acromegaly, a serum IGF-I level is the most appropriate test. This evaluation can be performed on a random blood test. On the contrary, growth hormone levels are only of value if obtained during an oral glucose tolerance test. The expected suppression of growth hormone with a glucose load is not seen. Glucose intolerance and hypertension are commonly found with both acromegaly and Cushing’s disease. Because the initial presentation of acromegaly can be amenorrhea, an elevated serum prolactin level, and a macroadenoma (>10 mm in diameter) on MRI, a serum IGF-I should be obtained in all patients who present with these findings.
Premature Ovarian Failure Premature ovarian failure is defined as amenorrhea with persistent estrogen deficiency and elevated FSH levels before age 40. This affects at least 1% of women.62,63 Most causes of premature ovarian failure are easily identified, such as chemotherapy and radiation therapy for cancer. Premature ovarian failure is usually irreversible, although spontaneous recovery of ovarian function can occur. Premature ovarian failure is a common cause of secondary amenorrhea, accounting for 4% to 18% of cases.64 This topic is examined in depth in Chapter 20. The etiology for the majority of patients with premature ovarian failure is unknown. However, for patients younger than age 30 presenting with amenorrhea, a karyotype should be obtained to rule out sex chromosome translocation, short arm deletions, or persistence of an occult Y chromosome, because these conditions are associated with an increased risk of ovarian malignancies. Some experts recommend that all patients with premature ovarian failure have a chromosomal analysis. However, in patients with amenorrhea secondary to premature ovarian failure, the single most common karyotype is XX (see Table 16-6). Gonadal Dysgenesis
Rare patients with gonadal dysgenesis may go through normal puberty and present with secondary amenorrhea, almost always before age 30. Women with secondary amenorrhea as a result of gonadal dysgenesis will usually have a normal 46,XX karyotype, although some will be found to have deletions, 47,XXX, or 46,XO. Patients who present with gonadal dysgenesis and a normal karyotype need to be assessed for a variety of other conditions, such as neurosensory deafness (Perrault’s syndrome), as well as fragile X syndrome, the most common genetic cause of developmental disorders. About 16% of women who are carriers of the
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Section 3 Adult Reproductive Endocrinology premutation allele for fragile X syndrome experience premature ovarian failure, particularly when familial premature ovarian failure or mental retardation is identified.9 When women with sporadic premature ovarian failure are screened, approximately 3% will be premutation carriers. Some females with premutation alleles may be affected with mild degrees of mental deficiency or learning disability. There is also an association of premature ovarian failure with autosomal-dominant eyelid abnormalities. This is known as blepharophimosis-ptosis-epicanthus inversus syndrome. This syndrome is caused by a mutation in FOXL2, which is a transcription gene factor found on chromosome 3.65,66 Several other autosomal disorders have been associated with ovarian failure; these will produce elevations of FSH without necessarily having oocyte depletion. Some of these include mutations of the phosphomannomutase 2 (PMM2) genes, the galactose-1-phosphate uridyltransferase (GALT) gene, the FSH receptor gene, and the autoimmune regulator gene (ARE), which is responsible for polyendocrinopathy-candidiasis-ectodermal dystrophy.67 Autoimmune Causes
A common form of premature ovarian failure is due to autoimmune disease. Up to 40% of women with premature ovarian failure may have autoimmune abnormalities, most commonly autoimmune thyroiditis resulting in hypothyroidism.68,69 Premature ovarian failure is also more common in women with insulin-dependent diabetes, myasthenia gravis, and parathyroid disease than in healthy women.70 In 10% to 60% of cases of Addison’s disease, autoimmune ovarian failure may also be present. Because these individuals are at increased risk for endocrine autoimmune conditions, patients should be evaluated every other year for occurrence of these abnormalities so early intervention can be achieved. Patients with unexplained premature ovarian failure should have a complete evaluation to exclude other autoimmune disorders; tests to perform include tests for calcium, phosphorus, fasting glucose, adrenal antibodies to 21-hydroxylase enzyme, free T4, thyrotropin, and thyroid antibodies. This evaluation should be repeated on a yearly or every other year basis.71 Screening for antiovarian antibodies is not warranted because the assays have poor sensitivity and specificity. Patients should be screened for adrenal disease with an evaluation for antiadrenal antibodies. If that test is positive, more sophisticated testing such as a corticotropin stimulation test is necessary. A fasting morning serum cortisol is not sufficiently sensitive. Premature Ovarian Failure: Other Causes
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Although elevated serum FSH levels are virtually synonymous with ovarian disorders, there are uncommon conditions that can raise FSH but are associated not with a primary ovarian problem but a central problem. These include pituitary adenomas that secrete FSH or specific enzyme defects such as 17-hydroxylase deficiency (P450c17) or galactose-1-phosphate uridyl transferase deficiency (galactosemia). There have been a few reports of single gonadotropin deficiency; the measurement of both LH and FSH together will uncover these unusual disorders. In premature ovarian failure you will always find elevations of both hormones; a single elevation is suspicious.72 Most of these abnormalities are due to
single-gene or amino acid substitutions. In these cases, an MRI of the pituitary will also uncover a pituitary adenoma that secretes these hormones, particularly if associated with an elevated α-subunit. However, these tumors are generally not associated with amenorrhea. There can also be mutations of the receptors for gonadotropins; these patients are diagnosed with resistant or insensitive ovary syndrome. These patients generally have secondary amenorrhea with normal secondary sexual characteristics and do not respond to gonadotropins and have small antral follicles on ultrasound.73 Mutations for the human FSH receptor gene have also been identified, both in females74 and males. Females display hypergonadotropic hypogonadism from FSH resistance. The phenotype ranges from absent to normal breast development and primary or secondary amenorrhea. This is a relatively uncommon finding, but is found predominantly in certain populations such as Finland (1% of females are heterozygotes). Mutations of the LH receptor in 46,XX females consist of normal sexual development and amenorrhea.26 Serum LH may be normal to increased, FSH is normal, follicular phase estradiol levels are normal, and progesterone is low. The uterus is small and the ovaries are consistent with anovulation. Diagnosis of Premature Ovarian Failure
The initial screen, as in all cases of amenorrhea, is with serum thyrotropin, prolactin, and FSH levels. The diagnosis of premature ovarian failure is made in the presence of elevated serum FSH, normal serum prolactin, and normal serum thyrotropin. Estradiol will also be decreased, and thus progesterone challenge will not result in withdrawal bleeding. Ovarian biopsies are usually not necessary in patients with premature ovarian failure. The costs and risks of surgical intervention are substantial, and they do not change patient management. A transvaginal ultrasound to assess antral follicle count and ovarian volume may be useful. Management of Premature Ovarian Failure
Patients with ovarian failure should be offered estrogen and progesterone replacement to maintain their secondary sexual characteristics and reduce the risk of osteoporosis. This can be easily achieved with combined oral contraceptives until the age of natural menopause as long as no contraindications to combined oral contraceptives are met. Some women who take lowdose exogenous estrogen therapy with a progestin, who have some ovarian follicles left with premature ovarian failure, can have spontaneous ovulation and conception is possible in rare cases.75
Disorders of the Genital Tract Although disorders of the genital tract are one of the less common cause of secondary amenorrhea, they are usually discovered relatively early in the diagnostic workup. Intrauterine adhesions (i.e., Asherman’s syndrome), although relatively common, accounts for only 7% of women presenting with secondary amenorrhea. Another infrequent cause of amenorrhea is outflow obstruction secondary to cervical stenosis. This is usually due to treatment of cervical dysplasia with modalities such as cryosurgery, electrocautery, or cold knife cone biopsy.
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Chapter 16 Amenorrhea Asherman’s Syndrome
Asherman’s syndrome is commonly used to describe the presence of intrauterine adhesions (or synechiae), most commonly secondary to uterine surgery. Patients are found to have Asherman’s syndrome after undergoing aggressive curettage for postpartum bleeding, after removal of multiple submucosal fibroids, or after metroplasty.76 Recently uterine artery embolization has also been associated with the development of Asherman’s syndrome; although its mechanism is not well understood, it is believed to be secondary to ischemia associated with the embolization procedure.77 Although the syndrome was first described as amenorrhea secondary to intrauterine synechiae, the presence of hypomenorrhea or amenorrhea is not considered a requirement for making this diagnosis today.76,78 Typically, the diagnosis is made when synechiae are seen at the time of a hysterosalpingogram. Adhesions can be isolated or diffuse dense scarring. Amenorrhea is most commonly seen with diffuse scarring. Regardless of bleeding pattern, patients typically have normal ovarian function and normal changes in their basal body temperature. Management of Asherman’s Syndrome
Asherman’s syndrome is treated with hysteroscopy, by lysing the synechiae with scissors, cautery, or laser. To prevent the reformation of adhesions, patients in the past have had an intrauterine device or a pediatric Foley catheter placed inside the uterine
cavity in the postoperative period. More recently, a balloon uterine stent that mimics the normal shape of the uterus has been developed. The balloon is typically kept inside the uterus for 7 to 10 days. Oral antibiotics are administered for variable lengths of time, typically for the length of treatment or a few days more. For patients who complain of cramping, nonsteroidal anti-inflammatory drugs are usually helpful. Although little prospective data are available, most clinicians give the patient 4 to 6 weeks of oral therapy with conjugated estrogens (2.5 mg) to regenerate the endometrium. This is followed by progestin to induce withdrawal bleed. If the initial therapy is unsuccessful, patients sometimes have to undergo multiple surgeries until menstruation is restored. Some authors report a subsequent pregnancy rate of 70% to 80% if menses can be restored, although this is sometimes difficult in severe cases. Patients who become pregnant may be at increased risk for complications, including premature labor, placenta accreta, placental previa, and postpartum hemorrhage.
Diagnostic Approach for Secondary Amenorrhea Evaluation of the woman with secondary amenorrhea begins with a careful history to detect sometimes subtle symptoms of one of a wide variety of conditions that can bring a halt to menses (Fig. 16-2). Physical examination will sometimes give hints of the most likely etiologies. Initial laboratory evaluation is an
History Physical examination
Hirsutism Acne
Laboratory evaluation
Progestin challenge No bleeding
Beta-hCG
TSH
Prolactin
FSH
Estrogen plus progestin challenge No bleeding
(FSH, E2 normal)
Estradiol Positive
Pregnancy
High
Hypothyroidism
Further evaluation required Asherman's Syndrome
High
Low or normal FSH, low E2
High FSH, low E2
Pituitary adenoma Hypothalamic dysfunction
Premature ovarian failure
Testosterone DHEAS 17 hydroxyprogesterone
High
PCOS or other hyperandrogenic condition Figure 16-2
Flow diagram in the evaluation of women with secondary amenorrhea, showing major decision points.
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Section 3 Adult Reproductive Endocrinology important step, not only to exclude physiologic causes of amenorrhea (e.g., pregnancy), but also to detect subtle hormonal conditions that often have no other symptoms or physical signs. Progestin challenge is then used to detect genital tract disorders and hypoestrogenemic states. By the second visit, enough information can be gathered to pursue more directed diagnostic tests to come up with a definite diagnosis.
Laboratory Evaluation
Basic to every history for women with amenorrhea is the menstrual history, sexual activity, and means of contraception. Years of irregular menses suggest PCOS but do not exclude pregnancy. Several modern means of contraception are prone to iatrogenic amenorrhea. In young women, eating and exercise habits must be explored. Although hypothalamic amenorrhea is common in underweight young women, so is unintended pregnancy. Young women are also at greater risk for premature ovarian failure related to abnormal karyotype. Genital tract disorders will almost always be accompanied by a history of gynecologic surgery, especially after a pregnancy. However, postpartum hemorrhage necessitating uterine curettage also brings up the possibility of Sheehan’s syndrome. The history should identify subtle symptoms of endocrinologic or systemic disorders, such as vaginal dryness associated with premature ovarian failure, galactorrhea often associated with hyperprolactinemia, and the increased hair growth often seem in women with PCOS. Systemic diseases often have associated symptoms, such as the weight gain associated with both hypothyroidism and Cushing’s syndrome. Acne and increased midline hair are often signs of hyperandrogenic conditions such as PCOS or adult-onset congenital adrenal hyperplasia. Clearly, many of these symptoms overlap and it is often tempting to prematurely jump to the diagnosis in a patient with classic symptoms of a common disorder. For this reason, it is important to let the history guide the additional tests, while not omitting parts of the basic workup.
All patients presenting with secondary amenorrhea should have an initial set of laboratory studies, including a pregnancy test and thyrotropin, prolactin, and FSH levels. A positive pregnancy test will initiate a workup for pregnancy to determine location and viability. Elevated thyrotropin or prolactin levels indicate a need to evaluate the patient further for hypothyroidism or pituitary adenoma, respectively. The results of the FSH measurement must be determined in relationship to other test results. An elevated FSH is an indication for further evaluation for premature ovarian failure. A normal or low FSH can be normal in patients with PCOS, and these patients will normally have withdrawal bleeding after a progestin challenge. In the presence of hypoestrogenemia as evidenced by low serum estradiol and failure to bleed after progestin challenge, either a low or normal FSH are abnormal and require an evaluation for hypothalamic disorders. Evaluation of androgens is indicated in women with amenorrhea and any sign of androgen excess such as hirsutism or acne. Although many women with PCOS will have modestly elevated androgens (see Chapter 15), the most important objective of measuring androgens in women with apparent PCOS is exclusion of other causes of hyperandrogenic amenorrhea, most notably androgen-producing tumors of the ovary and adrenal glands, Cushing’s syndrome, and adult-onset adrenal hyperplasia. Some women with elevated androgens will have minimal signs. This uncommon situation should be considered in women who do not appear to be hypoestrogenemic but do not bleed after progestin challenge. Evaluating both estradiol and androgen levels in these patients can sometimes help make the diagnosis.
Physical Examination
Progestin Challenge Test
The physical examination will often give obvious or subtle hints of the underlying cause of secondary amenorrhea. Patients with PCOS will often be overweight with increased hair on the upper lip, chin, chest, and inner thighs. These signs tend to occur at the time of menarche and are more pronounced in adolescents with adult-onset congenital adrenal hyperplasia. Sudden and dramatic hirsutism suggests an ovarian or adrenal tumor. Short stature and Turner’s syndrome can suggest premature ovarian failure with a genetic basis. Endocrinologic and systemic diseases often, but not always, have classic signs. Galactorrhea on breast examination suggests hyperprolactinemia, although only one third of women with elevated prolactin level will have this finding. Cushing’s syndrome is often associated with central obesity, moon face, abdominal striae, and “buffalo hump.” Gynecologic examination is occasionally illustrative in women with secondary amenorrhea. During speculum examination, significant stenosis of the external cervix or vaginal atrophy associated with hypoestrogenemia can be obvious. Bimanual examination will often detect the enlarged uterus of pregnancy, but less commonly the bilaterally enlarged ovaries seen in PCOS.
A traditional step early in the evaluation of secondary amenorrhea is the progestin challenge test. With a normal outflow tract and the presence of normal levels of circulating estrogen, menses will usually be induced by administering synthetic or natural progesterone. This can be in the form or medroxyprogesterone 10 mg a day for 7 days, intramuscular progesterone in oil 200 mg, or micronized progesterone 200 mg once a day for 7 days. Any amount of bleeding or spotting that occurs up to 7 days after the last progestin pill is considered to be a normal progestin challenge. Lack of withdrawal bleeding after a progestin challenge requires further evaluation. If not already evaluated, determination of serum FSH and estradiol is important to exclude premature ovarian failure or occult hypothalamic amenorrhea. Even in women with no clinical signs of androgen excess, serum total testosterone and DHEAS should be measured, because high levels of androgens can result in endometrial atrophy, thus preventing withdrawal bleeding. Failure to bleed after a progestin challenge is usually the result of estrogen deficiency or Asherman’s syndrome. To differentiate between these two, the patient should be pretreated
History
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As with the history, the physical examination should be used to guide the accessory tests. However, because many causes of secondary amenorrhea will not be obvious on physical examination, a comprehensive, stepwise approach to the basic workup is important.
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Chapter 16 Amenorrhea with estrogen (e.g., conjugated estrogens 1.25 mg daily for 6 to 8 weeks) and the progestin challenge should be repeated. Patients who do not bleed after administration of both estrogen and progestin are likely to have an anatomic problem that is preventing menses.
●
●
Imaging
Transvaginal ultrasound is perhaps the most common modality used to image the pelvic organs. In patients with secondary amenorrhea, this approach will rarely be helpful. Polycystic ovaries can often be seen in patients with PCOS. However, their absence does not exclude this diagnosis. Most anatomic abnormalities that cause amenorrhea, such as intrauterine adhesions, are difficult to see by ultrasound. Saline infusion sonohysterogram is more accurate. Hysterosalpingogram is typically used to visualize intrauterine adhesions. However, it should be performed in the evaluation of secondary amenorrhea only in patients who have a history of a predisposing factor.
●
●
●
●
Surgical Evaluation
The etiology of secondary amenorrhea can usually be determined without surgical evaluation. In some cases, diagnostic hysteroscopy may be necessary to assess the endometrial cavity when imaging modalities give ambiguous results.
●
●
PEARLS ●
The most common causes of primary amenorrhea are gonadal dysgenesis (almost half of all cases), müllerian agenesis (i.e.,
●
congenital absence of the uterus and vagina), hypothalamic disorders, and constitutional delay of puberty. The most common causes of secondary amenorrhea are premature ovarian failure, hyperprolactinemia, hypothalamic amenorrhea, and PCOS. The investigation of amenorrhea starts with three serum hormonal measurements: FSH, thyrotropin, and prolactin. Women with disorders of the genital tract (e.g., müllerian anomalies) have normal serum FSH, thyrotropin, and prolactin levels. The differential diagnosis for a blind vaginal pouch include müllerian agenesis and androgen insensitivity syndrome. Approximately 30% of patients with müllerian anomalies will have urinary tract anomalies, such as pelvic kidney, horseshoe kidney, unilateral renal agenesis, hydronephrosis, and ureteral duplication. Another 10% to 12% will have skeletal anomalies mostly associated with the spine. Forty percent of cases of primary amenorrhea have gonadal dysgenesis, and at least half of these patients have abnormal karyotypes. The diagnosis of Turner’s syndrome should be suspected in every young woman with sexual infantilism or poor growth after puberty, because these patients can present without the characteristic physical findings. The most common symptoms of a prolactin-secreting adenoma in women are galactorrhea, irregular periods, headaches, and infertility. Causes of hypothalamic amenorrhea are often related to energy deprivation syndromes, such as anorexia or stress.
REFERENCES 1. Stedman’s Medical Dictionary, 27th ed. Philadelphia, Lippincott Williams & Wilkins, 2000, p 56. 2. Herman-Giddens ME, Slora EJ, Wasserman RC, et al: Secondary sexual characteristics and menses in young girls seen in office practice: A study from the Pediatric Research in Office Settings network. Pediatr 99:505–512, 1997. 3. Practice Committee of the American Society for Reproductive Medicine: Current evaluation of amenorrhea. Fertil Steril 82(Suppl 1):S33–S39, 2004. 4. Timmreck LS, Reindollar RH: Contemporary issues in primary amenorrhea. Obstet Gynecol Clin North Am 30:287–302, 2003. 5. Pettersson F, Frieds H, Nillius SJ: Epidemiology of secondary amenorrhea. I. Incidence and prevalence rates. Am J Obstet Gynecol 117:80–86, 1973. 6. Bachmann G, Kemmerman E: Prevalence of oligomenorrhea and amenorrhea in a college population. Am J Obstet Gynecol 144:98–102, 1982. 7. Insler V: Gonadotrophin therapy: New trends and insights. Int J Fertil 33:85–97, 1988. 8. Doody KM, Carr BR: Amenorrhea. Obstet Gynecol Clin North Am 17:361–387, 1990. 9. Allingham-Hawkins DJ, Babul-Hirji R, Chitayat D, et al: Fragile X premutation is a significant risk factor for premature ovarian failure: The International Collaborative POF in fragile-X study/preliminary data. Am J Med Genet 83:322–325, 1999. 10. Layman L: Familial ovarian failure. In Lobo RA (ed). Perimenopause. New York, Springer-Verlag, 1997, pp 46–77. 11. Powell CN, Taggart DT, Drumheller TC, et al: Molecular and cytogenic studies of an X: Out to some translocation in a patient with premature ovarian failure in a review of the literature. Am J Med Genet 52:19–26, 1994.
12. Practice Committee of the American Society for Reproductive Medicine: Increased maternal cardiovascular mortality associated with pregnancy in women with Turner syndrome. Fertil Steril 83:1074–1075, 2005. 13. Jager RJ, Anvret M, Hall K, Scherer G: A human XY female with a frame shift mutation in the candidate testis-determining gene SRY. Nature 348:452–454, 1990. 14. Ostrer H: Sexual differentiation. Semin Reprod Med 18:41–49, 2000. 15. Reinhold C, Hricak H, Forstner R, et al: Primary amenorrhea: Evaluation with MR imaging. Radiology 203:383–390, 1997. 16. Aittomaki K, Eroila H, Kajanoja P: A population-based study of the incidence of müllerian aplasia in Finland. Fertil Steril 76:624–625, 2004. 17. Jagiello J: Prevalence of testicular feminization. Lancet 1:329–333, 1962. 18. Imbeaud S, Faure E, Lamarre I, et al: Insensitivity to anti-müllerian hormone due to a mutation in the human anti-müllerian hormone receptor. Nat Genet 11:382–388, 1995. 19. Petrozza JC, Gray MR, Davis AJ, Reindollar RH: Congenital absence of the uterus and vagina is not commonly transmitted as a dominant genetic trait: Outcomes of surrogate pregnancy. Fertil Steril 67:387, 1997. 20. Economy KE, Barnewolt C, Laufer MR: A comparison of MRI and laparoscopy in detecting pelvic structures in cases of vaginal agenesis. J Pediatr Adolesc Gynecol 15:101–104, 2002. 21. Stelling JR, Gray MR, Davis AJ, et al: Dominant transmission of imperforate hymen. Fertil Steril 74:1241–1244, 2000. 22. Wilson JD: Syndrome of androgen resistance. Biol Reprod 46:168–173, 1992. 23. Franco B, Guioli S, Pragliola A, et al: A gene deleted in Kallmann’s syndrome shares homology with neural cell adhesion and axonal pathfinding molecules. Nature 353:529–536, 1991. 24. Legouis R, Hardelin J, Levilliers J, et al: The candidate gene for the X-linked Kallmann syndrome encodes a protein related to adhesion molecules. Cell 67:423–435, 1991.
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25. Layman LC: Human gene mutations causing infertility. J Med Genet 39:153–161, 2003. 26. Toledo SPA, Brunner HG, Kraaij R, et al: An inactivating mutation of the luteinizing hormone receptor causes amenorrhea in a 46,XX female. J Clin Endocrinol Metab 81:3850–3854, 1996. 27. Layman LC, Cohen DP, Jin M, et al: Mutations in the gonadotropinreleasing hormone receptor gene cause hypogonadotropic hypogonadism. Nat Genet 18:14–15, 1998. 28. Goodman LR, Warren MP: The female athlete and menstrual function. Curr Opin Obstet Gynecol 17:466–470, 2005. 29. Montague CT, Farooqi S, Whitehead FP, et al: Congenital leptin deficiency is associated with severe early-onset obesity in humans. Nature 387:903–908, 1997. 30. Berga SL: Behaviorally induced reproductive compromise in women and men. Semin Reprod Endocrinol 15:47–53, 1997. 31. Drinkwater BL, Nilson K, Chesnut CH, et al:. Bone mineral content of amenorrheic and eumenorrheic athletes. NEJM 311:277–281, 1984. 32. Drinkwater BL, Nilson K, Ott S, Chesnut CH: Bone mineral density after resumption of menses in amenorrheic athletes. JAMA 256:380–382, 1986. 33. Gnoth C, Frank-Herrmann P, Schmoll A, et al: Cycle characteristics after discontinuation of oral contraceptives. Gynecol Endocrinol 16:307–317, 2002. 34. Schwallie PC, Assenzo JR: The effect of depo-medroxyprogesterone acetate on pituitary and ovarian function, and the return of fertility following its discontinuation: A review. Contraception 10:181–202, 1974. 35. Stein IF, Levinthal M: Amenorrhea associated with bilateral polycystic ovaries. Am J Obstet Gynecol 29:181–191, 1935. 36. Franks S: Polycystic ovary syndrome. NEJM 333:853–861, 1995. 37. Brenner SH, Lessing JB, Quagliarello J, Weiss JG: Hyperprolactinemia in associated pituitary prolactinomas. Obstet Gynecol 65:661–664, 1985. 38. Schlechte J, Dolan K, Sherman B, et al: The natural history of untreated hyperprolactinemia: A perspective analysis. J Clin Endocrinol Metab 68:412–418, 1989. 39. Costello RT: Subclinical adenoma of the pituitary gland. Am J Pathol 12:191–197, 1936. 40. Burrow GN, Wortzman G, Rewcastle MB, et al: Microadenomas of the pituitary and abnormal cellar tomograms in an unselected autopsy series. NEJM 304:156–158, 1981. 41. Hodgson SF, Randall RV, Holman CB, MacCarty CS: Empty sella syndrome. Med Clin North Am 56:897–907, 1972. 42. Sheehan HL, Murdoch R: Postpartum necrosis of the interior pituitary: Pathological and clinical aspects. J Obstet Gynaecol Br Emp 45:456–464, 1938. 43. Schlechte J, Sherman B, Halm IN, et al: Prolactin-secreting pituitary tumors. Endocr Rev 1:295–298, 1980. 44. Kleinberg DL, Noel GL, Frantz AG: Galactorrhea: A study of 235 cases including 48 with pituitary tumors. NEJM 296:589–600, 1977. 45. Jackson RD, Wortsman J, Malarkey WB: Characterization of a large molecular weight Prolactin in women with idiopathic hyperprolactinemia and normal menses. J Clin Endocrinol Metab 61:258–264, 1985. 46. Hattori N, Inagaki C: Anti-prolactin auto-antibodies cause a symptomatic hyperprolactinemia: Bioassay and clearance studies of prolactin-immunoglobulin G complex. J Clin Endocrinol Metab 82:3107–3110, 1997. 47. Schofl C, Schofl-Siegert B, Karstens JH, et al: Falsely low serum prolactin in two cases of invasive microprolactinoma. Pituitary 5:261–265, 2002. 48. Cook CB, Nippoldt TB, Kletter GB, et al: Naloxone increases the frequency of pulsatile leuteinizing hormone secretion in women with hyperprolactinemia. J Clin Endocrinol Metab 73:1099–1105, 1991. 49. Sauder SE, Frager M, Case GD, et al: Abnormal patterns of pulsatile leuteinizing hormone secretion in women with hyperprolactinemia and amenorrhea: Responses to bromocriptine. J Clin Endocrinol Metab 59:941–948, 1984. 50. Veldhuis JD, Hammond JM: Endocrine function after spontaneous infarction of the human pituitary: Report, review, and reappraisal. Endocr Rev 1:100–107, 1980. 51. Katz E, Schran HF, Adashi EY: Successful treatment of a prolactinproducing pituitary macroadenoma with intervaginal bromocriptine
52. 53.
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mesylate: A noble approach to intolerance to oral therapy. Obstet Gynecol 73:517–520, 1989. Turkalj I, Braun P, Krupp P: Surveillance of bromocriptine in pregnancy. JAMA 247:1589–1591, 1982. Cuellar FG: Bromocriptine mesylate (Parlodel) in the management of amenorrhea-galactorrhea associated with hyperprolactinemia. Obstet Gynecol 55:278–284, 1980. Passos PQ, Souza JJ, Musolino NR, Bronstein MD: Long-term follow up of prolactinomas: Normal prolactinemia after bromocriptine withdrawal. J Clin Endocrinol Metab 87:3578–3582, 2002. Mori H, Mori S, Saitoh Y, et al: Effects of bromocriptine on prolactinsecreting pituitary adenomas. Cancer 56:230–238, 1985. Rains CP, Bryson HM, Fitton A: Cabergoline. A review of its pharmacologic properties and therapeutic potential in the treatment of hyperprolactinemia and inhibition of lactation. Drugs 49:255, 1995. Robert E, Musatti L, Piscitelli G, Ferrari CI: Pregnancy outcome after treatment with the ergot derivative cabergoline. Reprod Toxicol 10:333–337, 1996. Webster J, Piscitelli G, Polli A, et al: The Cabergoline compared to a study group. A comparison of cabergoline and bromocriptine in the treatment of hyperprolactinemic amenorrhea. NEJM 331:904–909, 1994. Schlechte JA, Sherman BM, Chapler FK, Vangilder J: Long-term follow-up of women with surgical treated prolactin-secreting tumors. J Clin Endocrinol Metab 62:1296–1301, 1986. Molitch ME: Pregnancy and the hyperprolactinemic woman. NEJM 312:1364–1370, 1985. Bevan JS, Webster J, Berke CW, Scanlon MF: Dopamine agonist and pituitary tumor shrinkage. Endocr Rev 13:220–240, 1992. Jones GS, DeMoraes-Ruehsen M: A new syndrome of amenorrhea in association with hypergonadotropism and apparently normal ovarian follicular apparatus. Am J Obstet Gynecol 104:597–600, 1969. Van Campenhout J, Vauclair R, Maraghi K: Gonadotropin-resistant ovaries in primary amenorrhea. Obstet Gynecol 40:6–12, 1972. Anasti JN: Premature ovarian failure: An update. Fertil Steril 70:1–15, 1998. Schlessinger D, Herrera L, Crispni L, et al: Genes and translocation involved in POF. Am J Med Genet 111:328, 2002. Hundscheid RD, Smits AP, Vomis CM, et al: Female carriers for fragile-X pre-mutation have no increased risk for additional disease other than premature ovarian failure. Am J Med Genet 117:6, 2003. Laml T, Preyer J, Umek W, et al: Genetic disorders in premature ovarian failure. Hum Reprod Update 8:483–491, 2002. LeBarbera AR, Miller MM, Ober C, Rebar RW: Autoimmune etiology in premature ovarian failure. Am J Reprod Immunol Microbiol 16:115–122, 1988. Hoek A, Schoemaker J, Drexhage HA: Premature ovarian failure and ovarian autoimmunity. Endocr Rev 18:107–134, 1997. Nelson LM, Anasti JN, Flack MR: Premature ovarian failure. In Adashi EY, Rock JA, Rosenwalks Z (eds). Reproductive Endocrinology, Surgery and Technology. Philadelphia, Lippincott-Raven, 1996, pp 1393–1410. Bakaolv VK, Vanderhoof VH, Bondy CA, Nelson LM: Adrenal antibodies detect asymptomatic auto-immune adrenal insufficiency in young women with spontaneous premature ovarian failure. Hum Reprod 17:2096, 2002. Weiss J, Axelrod L, Whitcomb RW, et al: Hypogonadism caused by a single aminoacid substitution in the β-subunit of luteinizing hormone. NEJM 326:179–183, 1992. Aittomaki K, Herva R, Stenman U-H, et al: Clinical features of primary ovarian failure caused by a point mutation in the follicle-stimulating hormone receptor gene. J Clin Endocrinol Metab 81:3722–3726, 1996. Touraine P, Beau I, Gougeon A, et al: New natural inactivating mutations of the follicle-stimulating hormone receptor: Correlations between receptor function and phenotype. Mol Endocrinol 13:1844–1854, 1999. Rebar RW, Connolly HV: Clinical features of young women with hypergonadotropic amenorrhea. Fertil Steril 53:804–810, 1990. Schenker JG, Margalioth EJ: Intrauterine adhesion: An updated appraisal. Fertil Steril 37:593–610, 1982.
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Chapter 16 Amenorrhea 77. Davies C, Gibson M, Holt EM, Torrie EPH: Amenorrhea secondary to endometrial ablation and Asherman’s syndrome following uterine artery embolization. Clin Radiology 57:317–318, 2002.
78. Asherman JC: Amenorrhoea traumatica (atretica). J Obstet Gynecol Br Empire 55:23–30, 1948.
USEFUL WEB SITES • Asherman’s syndrome: An excellent source of information for physicians, families, and patients can be found at http://www.ashermans.org/. • An interesting internet site for patients with müllerian anomalies can be found at http://health.groups.yahoo.com/group/MullerianAnomalies/. Another patient resource can be found at http://www.inletmedical.org/ html/uterine_abnormality.htm. • An excellent resource is the Androgen Insensitivity Syndrome Support Group, which can be accessed at www.medhelp.org/www/ais/.
• A very strong patient advocacy group for patients with Turner’s syndrome can be found at http://www.turner-syndrome-us.org/. • An excellent support group for patients who are XY females is http://www.xyxo.org/. • An excellent link to patient support groups, literature, and ongoing research studies in premature ovarian failure can be found at http://www.pofsupport.org/.
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17
Lactation and Galactorrhea Elizabeth Ann Kennard and Elizabeth M. Hurd
INTRODUCTION Lactation is one of the most important physiologic processes necessary for the survival of mammalian offspring in the absence of human intervention. Breast milk contains species-specific nutrients and immune factors that allow for the appropriate growth and development of newborns. For breastfeeding to be successful, the mammary glands must develop and transform into milk-producing organs by a hormone-driven process referred to as lactogenesis. An understanding of this process has taken on increasing importance as the tremendous benefits of breastfeeding have become widely known in the past two decades. Galactorrhea, in its broadest sense, refers to the spontaneous flow of milk from the nipple at any time other than during breastfeeding. Derived from the Greek, galactorrhea literally means “milk flow.” Physiologic galactorrhea is experienced by many pregnant women late in gestation, as well as during the first few weeks or months after delivery when not breastfeeding or after cessation of breastfeeding. Clinically, the term galactorrhea is used to refer to abnormal or inappropriate secretion of breast milk or a milklike fluid. This term often applies to milk secretion that occurs more than 6 months after either cessation of breastfeeding or delivery when not breastfeeding or in a woman who has never been pregnant. However, it is important to be aware that nonphysiologic galactorrhea has no universally agreed-upon definition. Nonphysiologic galactorrhea can span the continuum from an incidental finding on examination to a significant social problem for the patient. The discharge may be unilateral or bilateral and it may occur spontaneously or only with nipple stimulation. Galactorrhea must be differentiated from a nipple discharge other than milk. The etiology can be idiopathic or related to any of a number of potentially serious underlying or iatrogenic causes. This chapter begins with a review of the normal physiology of the breast and lactation. The various etiologies of pathologic galactorrhea are discussed, followed by a discussion of evaluation, treatment, and long-term prognosis for women with this problem.
PROLACTIN A thorough comprehension of prolactin is required to understand both lactation and galactorrhea. Prolactin is responsible for the primary endocrine control of breast secretions, although multiple other hormones also influence breast milk production. Prolactin is a 198-amino acid polypeptide hormone secreted in pulsatile fashion from the anterior pituitary (adenohypophysis) by
specific cells referred to as lactotrophs.1 These cells have a common origin with the growth hormone-secreting cells (i.e., somatotrophs). Both prolactin and growth hormone are classified as somatomammotropic hormones based on their structural similarities. Due to its structural similarity to growth hormone, prolactin was the last pituitary hormone to be isolated. Prolactin has a short half-life of only 20 minutes and exists in heterogeneous forms, including big prolactin, a dimeric glycosylated form, and big big prolactin.2,3 Secretion has a circadian rhythm, with a higher average level of serum prolactin during sleep, especially during the rapid eye movement phase. The prolactin receptor is a member of the cytokine receptor family. It is a single transmembrane polypeptide found in multiple tissues in addition to the mammary glands, including the liver, adrenal glands, lungs, testes, and ovaries.4 The effects of prolactin in many of these tissues remains unknown.5
Neuroendocrinology of Prolactin Secretion The control of prolactin secretion by the anterior pituitary lies within the hypothalamus and is predominantly inhibitory. However, the hypothalamus releases both prolactin-inhibiting factors (PIF) and prolactin-releasing factors (PRF) that modulate the secretion of prolactin.6 Prolactin-inhibiting factors are released by the hypothalamus into the hypothalamo-hypophyseal portal system. Although other compounds have been shown to have inhibitory activity, dopamine appears to be the most important PIF.7 Interruption of the tuberoinfundibular tract and blocking dopamine receptors with “gene knockout” techniques both result in high prolactin levels.8 Gonadotropin-associated peptide and γ-aminobutyric acid are also PIFs.9 Prolactin secretion is regulated by a negative feedback loop wherein prolactin, acting via prolactin receptors in the median eminence, stimulates dopamine secretion.10 Dopamine acts via the adenylyl cyclase pathway to reduce prolactin secretion from the pituitary lactotrophs. The predominant dopamine receptor in the adenohypophysis is D2 (DRD2). Binding of dopamine to this receptor decreases cellular adenylyl cyclase activity and cyclic adenosine monophosphate. Although the major control mechanism for prolactin is inhibitory, the hypothalamus also releases PRFs, which stimulate lactotrophs to secrete prolactin (Table 17-1). The primary physiologic PRF appears to be vasoactive intestinal peptide. However, there appear to be two more clinically relevant PRFs.11,12 The ability of thyrotropin-releasing hormone (TRH) to act as a PRF is believed to be the basis of the association between hypothyroidism
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Section 3 Adult Reproductive Endocrinology Table 17-1 Prolactin Releasing Factors
Table 17-2 Hormones Required for Normal Mammary Development
Thyrotropin-releasing hormone
Estrogen
Serotonin
Progesterone
Vasoactive intestinal peptide
Prolactin
Opioids
Cortisol
Growth hormone-releasing hormone
Insulin
Gonadotropin-releasing hormone
Thyroxine Growth hormone
and hyperprolactinemia, a condition that resolves with thyroid hormone replacement. Serotonin appears to be another PRF; use of any of the various selective serotonin reuptake inhibitors (SSRIs) is commonly associated with hyperprolactinemia.
LACTATION The process of lactation requires normal breast development followed by appropriate hormonal and mechanical stimulation of the breast.
Breast Development Prenatal
Normal development in utero requires fetal exposure to many hormones, including estrogens, progesterone, prolactin, insulin, cortisol, thyroxine, and growth hormone (Table 17-2). The endocrine system is essential for the proper development and function of the mammary glands.13,14 Gene knockout studies have demonstrated the importance of each of these hormones in fetal mammary gland development.15. These hormones work through normal hormone–receptor interactions using local growth factors in many cases.16,17
Puberty
At puberty, estradiol is the major influence on breast development, and the breast contains both α and β estrogen receptors. However, multiple hormones are necessary for normal development, including all the hormones necessary for normal in utero development (see Table 17-2). Under the influence of rising estradiol levels at puberty, the breast increases in size and the areola gains pigmentation.18 Most breast development at puberty is adipocyte differentiation under the influence of estrogens. Estrogens stimulate the lactiferous ducts to branch extensively. The terminal alveoli unit, however, is rudimentary.
The Mature Breast Anatomy
The breasts consist of glands, fat, and connective tissue. The basic glandular unit consists of ducts and secretory lobules (Fig. 17-1). Twenty or more lactiferous ducts converge on the nipple. Each large duct is connected to smaller branching ducts and eventually lobules. The ducts are lined by a cuboidal or columnar epithelium, at the base of which are myoepithelial cells. Each lobule contains alveoli, milk glands lined by epithelium.19,20 In a nonactive state,
Nipple areolar complex
Lobules
Lactiferous sinus
Nipple
Sebaceous gland
Gland of Montgomery
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Figure 17-1 The breast and nipple–areolar complex. Distal ducts are lined by epithelial and myoephithelial cells. The breast lobules empty into lactiferous ducts, which terminate at the nipple. The glands of Montgomery are associated with sebaceous glands and terminate on the areola. (From Powell DE: The normal breast: Structure, function and epidemiology. In Powell DB, Stelling CB. The Diagnosis and Detection of Breast Disease. Mosby, 1995,)
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of the alveolar cells first leads to colostrum formation. Within the next 2 to 3 days, there is a relatively rapid onset of mature milk production.24
Cyclic Changes During the Menstrual Cycle
Breast changes occur with the different phases of the menstrual cycle. In the luteal phase, breast stromal water content and density increases under the influence of increased levels of circulating estrogen and progesterone. Clinically, the breasts become larger and fuller. On mammogram, breast tissue becomes more fibrous and dense, and thus more opaque. The “cloudy” mammography images make it difficult to detect small abnormalities in premenopausal women. Cell proliferation is also increased in the late luteal phase.
Pregnancy Breast development and lactogenesis during pregnancy occurs under the influence of multiple hormones, most notably prolactin, estrogen, and progesterone. Prolactin is secreted in large amounts by the decidua, and levels will be 5 to 10 times normal by the end of the first trimester.21 Under the influence of increased estrogen, the pituitary lactotrophs undergo hyperplasia. After delivery, prolactin declines to a normal baseline by 6 weeks postpartum and then pulses with breastfeeding. Lactogenesis
Final differentiation of the breast into a lactating organ occurs during pregnancy. Lactogenesis is a three-stage process whereby mammary glands develop the ability to produce and secrete milk.22 Starting in early pregnancy and ending within a week of parturition, the mammary glands are hormonally transformed from an undifferentiated state to a fully differentiated state with an established supply of mature milk. Stage I Lactogenesis
During this stage, mammary glands become competent to secrete milk. This stage begins early in gestation and is nearly complete by midpregnancy. As a result of rising levels of estrogen, progesterone, prolactin, and human placental lactogen, the terminal duct lobular units expand and secretory cells begin to differentiate. Prolactin induces the transcription of β-casein and lactalbumin genes.23 Mammary cells start accumulating large numbers of fat droplets. The character of secreted glandular fluid changes, with increases in lactose, total protein, and immunoglobulin concentrations and decreases in sodium and chloride concentrations. The mammary glands remain quiescent as a result of elevated estrogen and progesterone levels, but are prepared to initiate milk production around parturition. Stage II Lactogenesis
This stage begins at the time of birth and ends with the establishment of an appropriate milk supply. Delivery of the placenta results in a sudden drop in circulating progesterone levels. At the same time, both glucocorticoid and prolactin levels increase. This leads to increased synthesis of lactose. Lactose draws water by osmosis into the secretory vesicles. At the same time, synthesis of other milk components (e.g., nutrients and minerals) is increased under the influence of maternal insulin, growth hormone, cortisol, and parathyroid hormone. Secretion
Stage III Lactogenesis
The last phase of lactogenesis, also referred to as galactopoiesis or simply lactation, is defined as secretion and continued production of mature milk by the mammary glands once lactation has been established. Lactation occurs in response to sensory signals from suckling transmitted to the paraventricular and supraoptic nuclei in the brain. This results in release of oxytocin from the posterior pituitary. Oxytocin causes mammary myoepithelial cell contraction, resulting in milk letdown. As long as prolactin and oxytocin secretion are maintained and milk is removed from the mammary glands, milk production will be maintained. Milk production appears to require the presence of other hormones as well, including insulin and glucocorticoids. Suckling by the nursing young is the best-known physiologic stimulus of prolactin secretion. The mechanism of this classic neuroendocrine reflex appears to be decreased release of dopamine (a PIF) into portal blood.25 Breastfeeding
In nature, species-specific breast milk is necessary for survival of the neonate, because it is the only bioavailable source for the neonate of water, organic nutrients, and minerals. For human infants, breast milk gives the best opportunity for ideal growth and development because it contains a species-specific assortment of important nutrients and bioactive substances. These elements are critical during early developmental periods, especially for the brain, immune system, and intestinal tract. Colostrum, the first milk produced after parturition, is lower in fat than mature milk, but is higher in carbohydrates, protein, and antibodies. Mature milk is higher in calories as a result of higher fat content, but also contains antibodies and other bioactive factors. When human milk is unavailable, modern infant formulas are acceptable but incomplete substitutes. Most commonly made from cow’s milk or soybeans, formulas are similar to human milk in terms of water, fat, carbohydrates, and calories, but are devoid of antibodies and other bioactive factors. The exceptional benefits of human breast milk compared to formulas are so numerous that the American Academy of Pediatrics policy statement is that “pediatricians and other health care professionals should recommend human milk for all infants in whom breastfeeding is not specifically contraindicated.”26 Breastfeeding and Anovulation
Breastfeeding is associated with decreased ovarian function for a variable period of time. This is clinically manifested as anovluation, amenorrhea, hypoestrogenemia, and some degree of vaginal atrophy. The underlying mechanism of breastfeeding-related anovulation is related to the ability of suckling and prolactin release to inhibit gonadotropin-releasing hormone (GnRH) release. The amount of GnRH suppression varies with the amount and frequency of breastfeeding, use of infant supplements, and the weight and nutritional health of the mother. As a result of these variables, the length of time a breastfeeding woman will have amenorrhea is highly variable, and women should not rely on lactation to prevent pregnancy.
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Section 3 Adult Reproductive Endocrinology As many as 10% of breastfeeding women will ovulate within 10 weeks of giving birth.27 Two thirds of women who breastfeed for more than 9 months will resume ovulation and menstruation during that time. A small fraction of breastfeeding women will remain anovulatory and amenorrheic for more than 1 year. Involution
After cessation of breastfeeding (or after delivery in women not breastfeeding), postlactation changes result in involution of ducts and alveoli by apoptosis. Involution is a process whereby the mammary glands regress from their lactogenic state, resulting in a progressive decline and ultimate cessation of milk production. Prolactin levels will return to normal within 2 weeks of parturition if breastfeeding does not occur. After breastfeeding has been established, cessation of milk removal from the mammary glands will lead to rapid changes in the mammary tissue. Involution is complete in an average of 40 days after breastfeeding is stopped. Apoptosis of a large percentage of the alveolar cells and a remodeling of the mammary glands results in a return of the mammary glands to a mature quiescent state, although they never return to their prepregnant state.
GALACTORRHEA Nonphysiologic galactorrhea is a common problem that has been estimated to occur in approximately one fourth of all previously parous women sometime during their reproductive life. The condition is most common in women between ages 20 and 35 and is less common in nulligravid women.28 The most common pathologic condition resulting in galactorrhea is hyperprolactinemia, which has several possible underlying causes (Tables 17-3 and 17-4). Table 17-3 Pathologic Etiologies of Hyperprolactinemia Central nervous system disorders Pituitary tumors/lesions Adenomas (most common: prolactinomas, gonadotroph or nonfunctioning adenomas) Empty sella syndrome Hypothalamic tumors Craniopharyngioma Astrocytoma Hypophysitis Autoimmune Infections (e.g., tuberculosis, schistosomiasis) Sarcoidosis Hypothyroidism Chest wall irritation Thoracotomy Herpes zoster Atopic dermatitis Burns Breast surgery or tumors Thoracic neoplasms Ectopic prolactin secretion Bronchogenic carcinoma Renal adenocarcinoma Hypernephroma Gonadoblastoma
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Hyperprolactinemia Hyperprolactinemia occurs in less than 1% of the general population. When patients present with secondary amenorrhea, approximately 30% will be found to have hyperprolactinemia. When patients present with both galactorrhea and amenorrhea, 75% will have hyperprolactinemia. Approximately 30% of these patients will be found to have prolactin-secreting tumors.
Clinical Manifestations of Hyperprolactinemia The most common presenting symptoms of hyperprolactinemia are galactorrhea, infertility, menstrual dysfunction, and headaches. Galactorrhea is seen in more than 80% of hyperprolactinemic patients. Hyperprolactinemia is known to be causally related to several pathologic conditions (see Table 17-3). As noted, a physiologic response to hyperprolactinemia is anovulation.29,30 High levels of prolactin inhibit the pulsatile release of GnRH, thereby reducing pituitary release of both luteinizing hormone (LH) and folliclestimulating hormone (FSH). The LH surge is also inhibited. There is evidence that high serum prolactin levels also have a direct effect on the ovary.28 Hyperprolactinemia inhibits androgen synthesis, thereby reducing substrate for estrogen formation, and may block aromatase activity. All of these effects lead to hypoestrogenism and explain the disrupted or absent menstrual cycles in women with high prolactin levels. Elevated serum prolactin levels have a luteolytic effect that can disrupt the cycle. Elevated prolactin levels should be considered in the differential diagnosis of luteal phase disorders.
ETIOLOGIES OF HYPERPROLACTINEMIA Galactorrhea is most commonly a normal response of the breast to a normal or abnormal endocrine signal (i.e., hyperprolactinemia). Once elevated prolactin is detected, the goal of the clinician is to determine the underlying cause. After pregnancy is excluded, the clinician must assess the patient for drug causes, thyroid disease, Table 17-4 Drug Class Associated with Galactorrhea Neuroleptics Butyrophenones Phenothiazines Risperidone Antidepressants Selective serotonin reuptake inhibitors Tricyclic antidepressants Anti-emetics Metoclopramide Cardiovascular drugs Methyldopa Reserpine Verapamil Opiates Codeine, morphine, heroin Histamine(H2)-receptor antagonists Cimetidine
Decreased prolactin metabolism Renal failure Cirrhosis
Stimulation of lactotrophs High-dose oral contraceptives
Pseudocysesis false pregnancy
The listed drugs are only examples and do not represent a complete list
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Chapter 17 Lactation and Galactorrhea anatomic breast or chest wall abnormalities, and pituitary disorders (see Table 17-3).
Hypothyroidism
Whenever investigating hyperprolactinemia, clinicians should exclude an unrecognized early pregnancy. As discussed, the primary physiologic function of prolactin is to induce breast development and lactogenesis during pregnancy. By the end of the first trimester, prolactin levels will be 5 to 10 times the nonpregnant levels.
Hypothyroidism, even if subclinical, may result in elevated prolactin levels. When levels of circulating thyroxine are low, the lack of negative feedback on the hypothalamus results in increased release of thyrotropin-releasing hormone (TRH) into the portal circulation. As thyrotrophs are stimulated to release thyrotropin, lactotrophs are stimulated to release prolactin. This cross-reactivity is thought to be related to the embryologic derivation of both of these cell types from the same precursor cells.33 Thyroid replacement will uniformly reduce both thyrotropin and prolactin release, and alleviate the associated galactorrhea.34
Activities that Stimulate Prolactin Release
Chest Wall Lesions
When evaluating a patient’s serum prolactin levels, it is important to be aware of activities that can stimulate a temporary increase in prolactin through normal physiologic mechanisms. These include sleeping, eating, sexual intercourse, breast or chest stimulation, and stress. For this reason, if a borderline elevation of serum prolactin is detected on initial evaluation, it is prudent to avoid these stimulants by repeating the prolactin determination in the morning after fasting remote from any breast stimulation to avoid expensive evaluation of a fallacious prolactin elevation.31
Because chest stimulation can result in elevations of prolactin, it isn’t surprising that trauma or lesions of the chest wall may result in hyperprolactinemia and galactorrhea.35 Tumors, herpes zoster, spinal cord injury, and other lesions have been associated with hyperprolactinemia.36
Central Nervous System Disorders
Decreased Prolactin Metabolism
Physiologic Causes Pregnancy
Pituitary Adenomas
Pituitary adenomas can result in hyperprolactinemia by two different mechanisms. Prolactinomas, which account for approximately 70% of pituitary adenomas, secrete prolactin and are the most common cause of very high serum prolactin levels (usually >100 μg/L). Other types of pituitary adenomas result in hyperprolactinemia by a completely different mechanism. Clinically nonfunctioning adenomas usually originate from gonadotroph cells. They represent almost 30% of pituitary adenomas. Less common adenomas are those that originate from the somatotrophs (produce growth hormone), corticotrophs (secrete corticotropin), or thyrotrophs (secrete thyrotropin). The gonadotroph adenomas incommonly secrete FSH or LH. These tumors increase prolactin by compressing the pituitary stalk and interfering with the release of dopamine, the putative PIF. As a result of decreased exposure of the lactotrophs to the inhibitory influence of dopamine, prolactin levels increase, usually to the range of 30 to 100 μg/L. The nonfunctioning tumors usually present with neurologic symptoms rather than symptoms related to the hyperprolactinemia. These include visual impairment (bitemporal hemianopsia) and headache. Large tumors of the hypothalamus may also cause compression of the portal system that carries the prolactin inhibitors. Structural lesions such as empty sella syndrome or a cyst of Rathke’s pouch can also cause hyperprolactinemia and associated galactorrhea.32 The diagnosis and treatment of pituitary abnormalities are addressed in Chapter 22. Any disease that causes pituitary inflammation can result in hyperprolactinemia, probably as a result of decreased dopamine effect on lactotrophs. Uncommon causes of hypophysitis include autoimmune disease, infections (e.g., tuberculosis, schistosomiasis), and sarcoidosis.
Ectopic Prolactin Production
Rarely, malignant tumors have been reported to secrete prolactin, resulting in hyperprolactinemia. A list of some reported tumor types is given in Table 17-3.
Because most prolactin is excreted by the kidneys, renal disease is associated with galactorrhea due to high prolactin levels resulting from decreased excretion. This effect disappears once normal renal function is restored via transplant.37 Elevated prolactin has long been associated with cirrhosis of the liver, although the mechanisms for this remain unclear. Medications
Many psychotropic medications have been shown to cause galactorrhea via elevations of prolactin (see Table 17-4). The mechanism by which dopamine blocking agents (such as phenothiazines) increase prolactin is obvious, because they result in decreased exposure of lactotrophs to dopamine. It is less obvious how other centrally acting drugs increase prolactin levels, but this side effect is common with major neuroleptics such as haloperidol and antidepressants, including the tricyclics and the SSRIs.38–42 The SSRIs are probably the most frequent drug class associated with increased serum prolactin. Other commonly used drugs associated with hyperprolactinemia include antihypertensive medications such as methyldopa and verapamil.43 Protease inhibitors used for the treatment of human immunodeficiency virus infections have also been associated with hyperprolactinemia.44 The list of other medications associated with hyperprolactinemia is extensive. For this reason, the clinician should consult the product information for any medications being taken by women found to have hyperprolactinemia to determine if they could be associated with the galactorrhea.
EVALUATION OF GALACTORRHEA A general approach to the investigation and management of galactorrhea is outlined in Fig 17-2.
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History and Physical Exam
Palpable mass or discharge not consistent with milk
Evaluate with mammogram/ needle aspiration/breast surgeon referral
Figure 17-2
Galactorrhea/normal menses
TSH, PRL, pregnancy test
TSH and PRL
Normal
Elevated PRLx2
Elevated TSH
Elevated PRLx2
Observe
Pituitary image
Treat hypothyroidism
Pituitary image
Treat or observe
Repeat TSH, PRL
Pregnant
Treat hyperprolactinemia
Flow diagram for the evaluation of galactorrhea.
History It is important to determine the time of onset, duration, and frequency of galactorrhea. The amount and quality of the discharge should be defined as well as whether the leakage is spontaneous or needs to be induced. Galactorrhea associated with hyperprolactinemia is usually bilateral and spontaneous. Gynecologic history should include menstrual and contraception history, with special attention to the possibility of pregnancy. Obstetric history should include number of pregnancies, time since last delivery, menstrual cycle data, and medications. General symptoms can often give clues to underlying diseases associated with hyperprolactinemia. Symptoms of hypothyroidism include lethargy, weight gain, heat or cold intolerance, and nail and skin changes. Brain tumors are often associated with headaches and visual symptoms. History or symptoms of underlying renal or liver disease should be elicited. Finally, any history of chest lesion or trauma should be noted.
Physical Examination
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Galactorrhea/amenorrhea
The physical examination of the breast for the presence of masses and discharge should be performed. An important objective is to differentiate galactorrhea from other pathology. A dark or bloody secretion is clearly not milk, and a local cause should be sought. Palpable masses should be evaluated following normal protocols for this finding. The clinician should attempt to express the discharge or ask the patient to demonstrate the galactorrhea. The fluid may be milky, tan, green, or clear but should not be bloody. Placing a
drop of the fluid under the microscope and visualizing multiple fat droplets can easily verify galactorrhea. The presence of a bloody discharge or fluid is not galactorrhea and should prompt consideration of ductogram or other localized evaluation to rule out malignancy. An examination for galactorrhea should also include assessment for thyroid disorders, including palpation of the thyroid, and neurologic assessment, including visual fields.
Diagnostic Tests Serum Prolactin Levels
In the nonpregnant woman, the range of normal prolactin levels is from 1 to 20 ng/mL. There is a diurnal variation, such that prolactin levels are higher during sleep. During pregnancy, prolactin levels normally increase to as high as 300 ng/mL. Prolactin levels can be temporarily increased by breast stimulation related to medical or self-examination or sexual activity. However, in the nonpregnant patient, routine breast examination does not acutely alter serum prolactin levels, and thus measurement. If prolactin is elevated, the test should be repeated fasting and in the morning, when it would be expected to be lowest. The patient should be instructed to abstain from any breast or nipple stimulation immediately prior to the test. Other Laboratory Tests
Whenever hyperprolactinemia is suspected, a urine or blood pregnancy test and a serum thyrotropin level should be evaluated simultaneously with a serum prolactin level. In women at risk for kidney disease, a serum creatinine level should also be evaluated.
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Chapter 17 Lactation and Galactorrhea Imaging Studies
In the presence of reproducible hyperprolactinemia, evaluation of the pituitary and hypothalamus with magnetic resonance imagining is indicated to check for an intracranial lesion. Computed tomography can be used, but has the disadvantage of lower resolution. The most common brain tumor in women with hyperprolactinemia is a benign pituitary adenoma. These are classified as being either a microadenoma (<1 cm) or a macroadenoma (>1 cm). Their treatment and prognosis are discussed in Chapter 22. Postmenopausal women with no evidence of pituitary or hypothalamic lesions should be further evaluated with a chest radiogram and a mammogram, because hyperprolactinemia has been associated with both breast and lung cancer.
TREATMENT FOR GALACTORRHEA RELATED TO HYPERPROLACTINEMIA When galactorrhea is found to be a symptom of significant pathology, the treatment of the underlying problem becomes paramount. Many women will have resolution of their galactorrhea with appropriate therapy that normalizes their prolactin levels. When women are found to have a pituitary microadenoma or idiopathic hyperprolactinemia, the treatment decision is usually made based on the symptoms the patient is having. The most common symptoms associated with hyperprolactinemia are excessive galactorrhea, infertility, and hypoestrogenemic amenorrhea.
Indications for Treatment Excessive Galactorrhea
Galactorrhea itself is not a dangerous condition but can have significant impact on lifestyle if excessive. Whereas most women with minimal galactorrhea rarely request treatment for symptoms alone, women who have enough leakage to keep their clothing moist will often request treatment to avoid social embarrassment and/or the skin disorders associated with chronic dampness, including excoriation and fungal infections. Infertility
Women unable to achieve pregnancy found to have galactorrhea and hyperprolactinemia are at risk for ovulation dysfunction that can range from subclinical to obvious anovulation and amenorrhea. If a pituitary adenoma is diagnosed, the prognosis of this lesion during pregnancy should be discussed prior to therapy. Treatment with dopamine agonists will often result in pregnancy without further treatment.
increase estrogen will increase bone mass in these women.46 However, eumenorrheic women with galactorrhea demonstrate normal bone density and do not require treatment for this indication.47
Treatment Options The treatment of hyperprolactinemia is covered fully in Chapter 22. In brief, elevated prolactin levels related to pituitary causes can usually be decreased to the normal range using a dopamine agonist. In most cases, this will result in resolution of galactorrhea, associated menstrual abnormalities, and infertility. If infertility persists with normalized prolactin, ovulation induction medications may be used successfully in these patients.48 Conversely, if pregnancy is not desired, care must be taken to avoid pregnancy when hyperprolactinemia is corrected because a previously anovulatory patient has an 80% chance of becoming ovulatory after 6 months or less of treatment.49 If pregnancy is not desired, oral contraceptives can be used, especially if menstrual abnormalities persist. Oral contraceptives with higher levels of ethinyl estradiol (i.e., ≥ 50 μg) have been associated with galactorrhea and hyperprolactinemia.50 However, modern oral contraceptives (i.e., ≤ 35 μg) can be used in women with hyperprolactinemia with no measurable risk of enlargement of pituitary lesions.51 Galactorrhea not associated with elevated prolactin is uncommon. In the absence of other lesions, it is believed that some women have an increased sensitivity to normal levels of prolactin. Other women are thought to have elevated levels of abnormal prolactin that is not measured using normal assays. If these women have indications for treatment, a trial of dopamine agonist therapy is warranted.
PEARLS ●
●
●
●
●
●
Hypoestrogenemic Amenorrhea
●
Menstrual abnormalities in women with galactorrhea and hyperprolactinemia are often the result of hypoestrogenemia. The most significant long-term medical problem associated with this condition is decreased bone mineral density due to their hypoestrogenic state.45 Treatment to lower prolactin and thus
●
Lactation is a complex multistep process under hormonal control. Breast milk is a neonate’s best source of water, organic nutrients, minerals, and bioactive substances. Pregnancy and hypothyroidism should be excluded in women with hyperprolactinemia. Galactorrhea of endocrine origin is often associated with amenorrhea. Galactorrhea associated with a normal menstrual cycle and a normal serum prolactin level is usually not associated with a pituitary tumor. Centrally acting drugs associated with galactorrhea include antipsychotics, antidepressants (e.g., imipramines, SSRIs) opiates, histamine (H2) receptor antagonists (e.g., cimetidine), and calcium channel blockers. The highest levels of serum prolactin are usually related to pituitary prolactinomas; lower levels can be seen with any lesion that compresses the pituitary stalk. Treating hyperprolactinemia with dopamine agonists will resolve galactorrhea and usually result in normalized menstrual cycles and fertility.
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51. Testa G, Vegetti W, Motta T, et al: Two-year treatment with oral contraceptives in hyperprolactinemic patients. Contraception 58:69–73, 1998. 52. Powell DE, Stelling CB: The normal breast: Structure, function and epidemiology. In The Diagnosis and Detection of Breast Disease. St. Louis, Mosby, 1994.
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Section 3 Adult Reproductive Endocrinology Chapter
18
Hirsutism Cynthia Abacan and Charles Faiman
INTRODUCTION Hirsutism refers to excessive hair growth in areas of the body under androgen control. Although hirsutism may occur in both men and women, it is typically only a problem for women. The areas in which normally only postpubescent males have terminal hair growth include the upper lip, chin, chest, back, buttocks, and inner thigh. Hirsutism is a cosmetic concern from the patient’s perspective. Various studies have shown an increased prevalence of social fear and depression among hirsute women.1,2 Whether or not these psychological symptoms have a neuroendocrine basis remains to be elucidated.3 The old adage that “Even a single hair casts its own shadow” may help the clinician deal with the problem objectively. Indeed, even minor degrees of hirsutism may have major consequences on self-image in certain individuals. Hirsutism needs to be differentiated from hypertrichosis. Hypertrichosis, referring to a diffuse increase in fine (vellus) hair that is not androgen dependent, may be congenital or associated with other medical conditions such as hypothyroidism or porphyria or may be associated with certain medications4,5 (Table 18-1). From a practical viewpoint, hirsutism is most often the manifestation of an underlying benign process. However, the association of androgen excess with insulin resistance and its concomitant metabolic consequences is of increasing concern.
used and the population studied. There is a wide degree of variation of what is considered normal hair growth. It is influenced heavily by the woman’s race and cultural background. It is generally accepted that women of Mediterranean origin have more body hair per unit area than Asians of the mongolian race. Traditionally, hirsutism has been quantified according to criteria established by Ferriman and Gallwey.8 In this system, nine body areas sensitive to androgen are graded from 0 (absent), through 1 (minimal terminal hair) to 4 (frank virilization). In this scoring system, the minimum score is 0 and the maximum is 36. In their study of 161 women, Ferriman and Gallwey noted that 9.9% had a score of greater than 5, 4.3% had a score above 7, and 1.2% obtained a score above 10. In general, a score of 8 or more has been considered to represent hirsutism. Various investigators have modified this scoring system over the years.9,10 Hirsutism scores vary widely among women of different ethnic origins (Table 18-2). Consequently, a numeric cutoff point for hirsutism needs to be defined in the context of the population of interest. In clinical practice, the use of a standardized scoring system is impractical. It is limited by subjective variability as well as varying cutoff points depending on ethnicity.5,11 From a practical point of view, hirsutism may be classified simply as mild, moderate, or severe. Specifying the affected areas is helpful in following the response to therapy.
PREVALENCE
THE HAIR FOLLICLE AND HAIR GROWTH CYCLE
It has been estimated that between 5% and 15% of women surveyed are affected with hirsutism, although the exact prevalence remains uncertain.6,7 These estimates depend on the criteria
The hair follicle is composed of dermal and epidermal components.12 Together with the arrector pili muscles and sebaceous glands, it forms the pilosebaceous unit. In androgen-sensitive
Table 18-1 Disorders and Drugs Causing Hypertrichosis
Table 18-2 Prevalence of Hirsutism in General Population Surveys
Disorders
Drugs
Thyroid disorders
Diphenylhydantoin
Population
Anorexia nervosa
Diazoxide
8% 7.1%
Knochenhauer ES, et al.158
Minoxidil
174 white women 195 black women
≥ 6
Dermatologic disorders
Cyclosporine
145 white women
≥8
7.1%
Asuncion M, et al.159
Streptomycin
4780 Kashmiri women ≥ 6
Prolonged administration of cortisone
531 Thai women
Penicillamine Psoralens
*Ferriman-Gallwey Score8
Criterion for Prevalence Hirsutism* of Hirsutism Authors
≥3
10.5%
Zargar AH, et al.160
2%
Cheedwadhanaraks S, et al.11
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Section 3 Adult Reproductive Endocrinology areas, each pilosebaceous unit has the capacity to differentiate into a terminal hair or into a sebaceous follicle. There are three main types of human hair follicles. These have been classified according to the size and depth of the follicle13:
Adrenal Glands
Ovaries
• Vellus hair follicles—fine, soft, and poorly pigmented hair found in most areas of the body • Medium follicles—thicker than vellus hair, penetrating deeper into the dermis, pigmented, and present in the upper arms, lower legs, and in the transitional zone between thick and fine hair regions • Terminal follicles—large, thick, pigmented hair, penetrating into the entire skin layer and found in the scalp, axillae, and pubic areas. In men, these are also found in the face and chest. The hair follicle undergoes repetitive cycles of growth postnatally.14 In fact, the hair growth cycle has been described as a recapitulation of embryogenesis.15 The hair cycle includes three phases: telogen (resting), anagen (growth), and catagen (shortening). In humans, hair growth occurs in a mosaic pattern, where the activity of each follicle is independent of its neighbors.15 In human scalp hair, 85% to 90% of the hair follicles are in anagen, 13% are in telogen, and less than 1% are in catagen at any given time.16 Factors mediating the close relationship between the epidermal and dermal components of the hair follicle are the subject of increasing studies. Different growth factors have been implicated in the control of hair development—epidermal growth factor, fibroblast growth factor, tumor necrosis factor-β, and insulin-like growth factors.17–20 Hair growth is therefore the culmination of interactions between an organism’s genetic make-up influenced by environmental signals from the endocrine and paracrine environment. Although the morphologic changes in the hair growth cycle are well documented, the molecular mechanisms underlying the regulation of the phases of hair growth are still not well understood.
ANDROGENS AND HAIR GROWTH Hirsutism is caused by high circulating androgen levels and/or by an increased sensitivity of the hair follicle to androgen exposure. Androgen excess has been described as the most frequent endocrine disorder in women of reproductive age.21 It is believed to occur in 75% to 85% of women with hirsutism.7 Hirsutism is only one of the clinical signs of androgen excess, which also includes androgenic alopecia, acne, and infertility.22 Much of our current knowledge about the role of androgens in adult human hair growth is based on the early observations of individuals with testicular feminization (androgen resistance) syndrome or with pseudovaginal perineoscrotal hypospadias (now known as steroid 5α-reductase 2 deficiency) or those who underwent castration. All of these conditions are characterized by decreased to absent androgen level or action, leading to variations in hair growth pattern observed phenotypically.
Androgen Production and Metabolism In women, direct secretion from the ovaries and the adrenal glands
264 accounts for 30% to 50% of circulating testosterone (Fig. 18-1).
30%-50% Circulating Testosterone 50%-70%
Peripheral conversion of androgen precursors in skin, liver and adipose tissue
Figure 18-1
Testosterone production in premenopausal women.
Table 18-3 Role of SHBG in the Regulation of Free Estrogen and Testosterone High estrogen state: free estrogen increases and free testosterone decreases Normal estrogenic state: balance High androgen state: free estrogen decreases and free testosterone increases
The rest arises from peripheral conversion of androgen precursors to testosterone, mainly in the skin, liver, and adipose tissue.23 Androgen precursors include androstenedione, dehydroepiandrosterone (DHEA), and dehydroepiandrosterone sulfate (DHEAS). Testosterone is the most important circulating androgen. It is present either protein-bound or free in the circulation. Approximately 98% to 99% of plasma testosterone is protein bound—with higher affinity to sex hormone-binding globulin (SHBG) and more loosely to the larger pool of albumin and other proteins. Various factors affect the hepatic production of SHBG. Androgens, insulin, and growth hormone lower SHBG levels, whereas estrogens and thyroid hormone excess result in increased SHBG levels.24 Because of the greater affinity of SHBG to testosterone compared to estradiol, changes in SHBG concentration produce a much greater alteration in the percentage of unbound testosterone than of unbound estradiol. This relationship has been characterized as a see-saw, with SHBG as the fulcrum whose position moves in response to estrogens and androgens (Table 18-3).25 In this way the balance between the levels of free estrogen and free testosterone is determined by the amount of SHBG, whose concentration is determined by these hormones. Accordingly, SHBG acts to amplify the tissue exposure and response to androgen/estrogen balance.
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Chapter 18 Hirsutism The free fraction of plasma testosterone is the biologically active portion. It is believed to enter the target cell by passive diffusion and then binds to the nuclear androgen receptor. Androgen binding leads to an allosteric conformational change, which in turn leads to receptor dimerization, nuclear transport, and target DNA interaction.26–28 These events culminate in target gene transcription. Both testosterone and dihydrotestosterone bind to the same receptor but with different affinities, that for dihydrotestosterone being much greater than that for testosterone.29 The affinity for DHEA and androstenedione is markedly less.30
Site of Androgen Action in the Skin The skin is a major site for the peripheral conversion of weak androgen precursors to active androgens.30 DHEA and DHEAS have little androgenic activity. However, these may be converted to androstenedione and subsequently to testosterone in the adrenal glands and in the peripheral tissues. The active androgen in the skin is dihydrotestosterone.23 Conversion from the testosterone precursor is catalyzed by the enzyme 5α-reductase. Two forms of 5α-reductase are known. Type 1 is found mainly in nongenital skin; the gene responsible is found on chromosome 5. Type 2, encoded on chromosome 2, is primarily found in androgen target tissue such as the prostate, epididymis, seminal vesicle, and genital skin.31 The two types share 50% homology. Dermal papilla cells taken from androgen-dependent areas such as the beard have been demonstrated to express a greater number of androgen receptors as compared to nonbalding scalp cells.15 Higher levels of 5α-reductase activity have also been demonstrated in beard cells.32 The varying sites of expression of the androgen receptor in the different cell types in the skin likely account for the diverse effects of androgens in the skin. These likely account for the disparity in hair distribution and thickness observed among hirsute individuals with similar androgen levels. The increased sensitivity of the pilosebaceous unit to normal levels of androgen is believed to be due to enhanced peripheral 5α-reductase activity, polymorphisms of the androgen receptor, or altered androgen metabolism.
ETIOLOGY OF HIRSUTISM Hirsutism is a sign of increased androgen level or increased sensitivity of the hair follicles to androgen. Hyperandrogenemia is seen in 85% of patients with moderately severe hirsutism.6 Hirsutism may be idiopathic or due to androgen excess from either the ovary or the adrenal gland. Conditions associated with androgen excess from the ovaries include polycystic ovary syndrome (PCOS), hyperthecosis, and androgen-secreting ovarian tumors. Adrenal causes of androgen excess include Cushing’s syndrome, congenital adrenal hyperplasia (CAH), and androgen-secreting tumors. Most hirsute women will have PCOS33,34 (Fig. 18-2).
Idiopathic Hirsutism The most widely accepted definition of idiopathic hirsutism includes normal androgen levels and normal ovulatory function in a hirsute patient.35 Using these criteria, the prevalence of
PCOS IH
0.2% 0.7% 2.6% 3.8% 11.2%
HAIRAN-S 21-NCCAH 21-CAH
82%
Androgen-secreting Neoplasm
Figure 18-2 Causes of androgen excess. PCOS, polycystic ovary syndrome; IH, idiopathic hirsutism (includes patients with normal or elevated androgens without a specific diagnosis); HAIRAN, hyperandrogenic insulin-resistant acanthosis nigricans; 21-NCCAH, 21-hydroxylase deficient nonclassic congenital adrenal hyperplasia; 21-CAH, 21-hydroxylase deficient classic adrenal hyperplasia. (Data from Azziz R, et al: Androgen excess in women: Experience with over 1000 consecutive patients. JCEM 89:453–462, 2004).
idiopathic hirsutism has been estimated to be between 5% and 15%.36,37 Among 64 hirsute women claiming regular menses at intervals shorter than 35 days, 25 (39%) had an anovulatory cycle documented by a day 22 to 24 serum progesterone level of less than 4 ng/mL.36
Polycystic Ovary Syndrome Although initially described in 1935 by Stein and Leventhal, a uniform definition for PCOS still does not exist.38 At the recent joint meeting of the European Society for Human Reproduction and the American Society of Reproductive Medicine, it was suggested that the diagnosis of PCOS is met when at least two of the three following elements are present: hyperandrogenism, chronic anovulation, and polycystic ovaries.39 The different diagnostic criteria for PCOS reflect the heterogeneous nature of this disorder. PCOS is still a diagnosis of exclusion. The prevalence of PCOS is estimated to be at 5% to 7% of reproductive age women.40 It is the most common cause of anovulatory infertility. Polycystic ovary syndrome needs to be distinguished from polycystic ovaries alone. Although most women with PCOS have polycystic ovaries, a substantial population of normal women does as well. Polycystic ovarian morphology may be found in 20% or more of women of reproductive age.41,42 The significance of polycystic ovaries alone is unclear given that it seems to have no impact on fertility.43 Women with PCOS present with some or all of the following clinical features: oligomenorrhea, infertility, hirsutism, acne, alopecia, or obesity. It is important to remember that the syndrome has multiple components—reproductive, metabolic, and cardiovascular—that have health implications throughout the woman’s life.44 Insulin resistance, which refers to the diminished ability of insulin to exert its metabolic effects, is now thought to play a central role in PCOS.45,46 Beta-cell dysfunction, independent of insulin resistance, is also thought to contribute to the pathogenesis of the complications of PCOS.47 Women with PCOS have higher basal insulin concentrations and an increased prevalence of central
265
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Section 3 Adult Reproductive Endocrinology obesity, type 2 diabetes mellitus, and hypertension.48 An estimated 50% to 70% of women with PCOS have insulin resistance.49 Not surprisingly, insulin resistance in women with PCOS is associated with obesity but may also be present in lean women with PCOS.50–52 The consequent hyperinsulinemia is believed to lead to androgen excess through several mechanisms: (1) stimulation of ovarian androgen production, (2) stimulation of adrenal androgen biosynthesis, (3) stimulation of luteinizing hormone (LH) release, and (4) decreasing hepatic SHBG production.53–56 Differentiating those women with PCOS with insulin resistance from those without insulin resistance therefore becomes important given the metabolic consequences and required surveillance for these women.57–59 Considering the paucity of data on the use of simple laboratory markers of insulin resistance in predicting risks and therapeutic response in women with PCOS, it is recommended that the best clinical approach may be the heightened surveillance in all patients for the clinical sequelae of insulin resistance, such as glucose intolerance, dyslipidemia, and hypertension.60
Congenital Adrenal Hyperplasia CAH is a family of autosomal recessive disorders resulting from deficiency in one of the five enzymes necessary for the biosynthesis of cortisol and aldosterone.61 Clinical features depend on the degree of the enzyme defect. The classic forms of neonatal virilization result from a severe enzyme deficiency. Nonclassic forms, due to a less severe enzyme deficiency, may result in delayed signs of androgen excess. In this chapter, the three enzyme deficiencies that result in features of postnatal androgen excess are discussed (see Chapter 2 for details on steroidogenesis). 21-Hydroxylase Deficiency
This enzyme deficiency accounts for the majority (90% to 95%) of CAH cases.61,62 There is a wide variability in phenotypic expression, depending on the extent of the enzyme impairment. All the various forms of 21-hydroxylase deficiency are caused by either homozygous or compound heterozygous mutations in the CYP21A2 gene. The incidence is estimated to be 1:15,000 live births for the severe classic form of CAH.63 The prevalence is higher in certain ethnic groups, such as the Ashkenazi Jews. Nonclassic 21-hydroxylase deficiency (21-OHD) has been reported to occur in from 1% to 10% of hyperandrogenic women.64 Affected individuals produce normal amounts of cortisol and aldosterone at the expense of elevated sex hormone precursors. Onset of symptoms is variable. Some may present with premature pubarche; others may be diagnosed after puberty when they present with symptoms resulting from androgen excess—menstrual irregularity, hirsutism, acne, or infertility. They are clinically indistinguishable from women with PCOS. Up to 50% of affected women (with nonclassic 21-OHD) have been reported to have polycystic ovaries on ultrasound examination.65 Serum androgen levels are comparable with those seen in PCOS as well.66 Measurement of 17-hydroxyprogesterone (basal or stimulated) currently is the main test used to diagnose nonclassic 21-OHD. 11-Hydroxylase Deficiency
This is the second most common cause of CAH, seen in about 5%
266 to 8% of cases.63 Clinical features are similar to the virilizing form
of CAH. However, hypertension is a clinical feature believed to be due to the excess production of the mineralocorticoid deoxycorticosterone. Hypokalemia may be seen as well. Mild, late-onset presentations have been reported. Diagnosis is based on the response to a corticotropin stimulation test similar to 21-OHD; however, in this condition, deoxycorticosterone and 11-deoxycortisol are elevated. 3-Hydroxysteroid Dehydrogenase Deficiency
This is a rare form of CAH due to mutations within the HSD3B2 gene. Salt-losing and nonsalt-losing types have been identified. The diagnosis is established by demonstrating an increased corticotropin-stimulated ratio of Δ5-17-hydroxypregnenolone to 17-hydroxyprogesterone or to cortisol.
Androgen-secreting Tumors Adrenal Tumors
A purely androgen-secreting adrenal tumor is rare. More frequently, a mixed picture of Cushing’s syndrome with virilization is seen in adults.67 In a review of cases of androgen excess seen in the Mayo Clinic from 1946 to 2002, 11 female patients were identified to have pure androgen-secreting adrenal tumors. Five of these were malignant.68 Malignant tumors were bigger (9.8 cm vs. 4.2 cm) and heavier (232 g vs. 44 g). Surprisingly, mortality was reported in only one patient, a finding in marked contrast to the lower survival rates observed in other forms of adrenocortical carcinoma.69 Ovarian Tumors
Androgen-secreting ovarian tumors are also rare.70 Sertoli-Leydig cell tumors are the most common virilizing ovarian tumor and account for 0.5% of all ovarian neoplasms; however, even nonfunctional ovarian tumors may cause hyperandrogenism, probably mediated by stimulation of stromal cells adjacent to the tumor.71,72
Ovarian Hyperthecosis Hyperthecosis refers to the nests of luteinized theca in the ovarian stroma. There is a considerable clinical overlap between patients with PCOS and those with ovarian hyperthecosis. The latter, however, often present with a more severe form of hyperandrogenism with associated virilization. Laboratory evaluation typically shows a normal serum DHEAS level with extremely elevated testosterone levels, often greater than 200 ng/dL.71
Hyperandrogenism, Insulin Resistance, and Acanthosis Nigricans (HAIRAN) Syndrome A unique disorder of severe insulin resistance associated with hyperandrogenism, HAIRAN syndrome is becoming more widely recognized. It is characterized as follows:73 (1) early age of onset of hyperandrogenism, (2) acanthosis nigricans, (3) marked insulin resistance, (4) positive correlation of the severity of the insulin resistance with the severity of androgen excess, (5) ovarian source for the androgen overproduction, and (6) ovarian hyperthecosis. Most affected women will have normal glucose concentration at the expense of markedly elevated levels of circulating insulin (>80 μU/mL fasting insulin and/or
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Chapter 18 Hirsutism >500 μU/mL after an oral glucose challenge).7 The molecular cause of the insulin resistance in patients with HAIRAN syndrome is still not well understood.
Cushing’s Syndrome
the patient’s benefit and satisfaction. Most underlying etiologies for hirsutism are benign, considering that it may take months to even years of androgen exposure to transform vellus hair to terminal hair.81 Onset of Symptoms
The reported incidence of hirsutism in patients with Cushing’s syndrome is 64% to 81%.74 However, Cushing’s syndrome is a rare cause of hirsutism. Increased adrenal androgen production may accompany the increased production of cortisol. The onset of hirsutism is often distinct from menarche. There may also be increased growth of lanugo hair as a result of the hypercortisolism.75
Increased androgen exposure of the pilosebaceous unit occurs at puberty. Hence, hirsutism often starts at around this time or a few years thereafter. On occasion, it may accompany an early adrenarche. Not infrequently, increased facial hair development in women occurs postmenopausally. It is thought to result from the altered estrogen/androgen balance.82 Rapid hair growth of recent onset should be viewed with suspicion.
Hyperprolactinemia
Extent of Hair Growth
Elevated prolactin levels have been noted in some hirsute women. In a study of 158 women with hirsutism, elevated prolactin was noted in 6% of the women.76 The exact relationship between hyperprolactinemia and hirsutism is still unclear. It is postulated that elevated prolactin level may increase androgen production via an effect on the adrenal cortex. Use of dopamine agonists in hirsute, hyperprolactinemic women has been shown not only to reduce serum androgen levels, but also to improve hirsutism scores.77 On the other hand, the use of bromocriptine in women with PCOS but without hyperprolactinemia has not been demonstrated to alter serum androgen levels.78
Drug-Induced Hirsutism Multiple medications have been implicated in hirsutism. Anabolic steroids such as danazol, oral contraceptives containing progestins that are 19-nortestosterone derivatives, and medications that can increase serum prolactin have been implicated.4 Among 19-nortestosterone derivatives, first-generation (norethynodrel) and second-generation progestins (norethindrone and its metabolites; levonorgestrel and its derivatives) are more androgenic than the third-generation progestins (desogestrel and norgestimate).79 With the increasing use of testosterone replacement in postmenopausal women, iatrogenic hirsutism will likely occur more frequently.80
APPROACH TO THE PATIENT WITH HIRSUTISM Patients’ Goals In evaluating hirsutism, it is important to find out what is of most concern for the patient. Often, cosmetic concerns are paramount. On the other hand, some women will present because of concern for the metabolic complications often thought to be associated with hirsutism. It is becoming widely appreciated that hypertension, dyslipidemia, and type 2 diabetes mellitus are increasingly recognized to be closely linked to PCOS.
History A thorough history is necessary in the evaluation of a woman with hirsutism. Recognizing the patient’s concerns and goals for the visit will allow the physician to tailor the eventual therapy to
The patient will often volunteer the areas of concern, particularly if these involve the face or the chin. However, areas that can be covered by clothing are often overlooked. Hence, one also needs to ask about hair growth in the upper chest, around the areolae, in the upper abdomen, buttocks, and the lateral area of the pubis to the inner thighs. Hair growth in the upper back also needs to be assessed because it is not noticeable to the patient. Knowledge of the method and frequency of depilation is helpful. This gives the clinician an idea of the severity of the hirsutism as well as efficacy of therapy. The clinician may make a false impression of the severity of the problem because a number of women may go to their doctor’s office with the areas of concern recently waxed or shaved. Associated Symptoms Acne
Androgen action on the pilosebaceous unit leads to increased sebum production. Sebum production is important in the process of acne development. As is the case with hirsutism, estrogen and androgen appear to have opposing roles in this process. Alopecia
Androgenic alopecia, another distressing condition associated with androgen excess, needs to be differentiated from other types of alopecia. Different patterns of hair loss have been described:83 • Progressive thinning of the crown with preservation of the frontal hairline • Male-pattern form with bitemporal recession. Virilization
Rapid progression of hirsutism associated with virilization is suggestive of an androgen-secreting neoplasm of the ovary or the adrenal gland. Deepening of the voice, increased muscle mass, increased libido, and clitoral enlargement are clues suggestive of androgen excess. Menstrual History
Oligomenorrhea is one of the features of PCOS. In adolescents, oligomenorrhea that persists after the first few years from the menarche may be an early sign of PCOS.30 Regular menses, however, do not predict normal androgen status in hirsute women. Although 40% of hirsute women will have regular menses, on evaluation, half of these women will be found to have elevated levels of one or more androgens.84
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Section 3 Adult Reproductive Endocrinology Regular menses do not prove normal androgen status or reliably normal ovulatory/luteal function. In one study, 39% of women reporting normal menstrual cycles actually had oligoovulation/anovulation when basal body temperature and day 22 to 24 progesterone levels were measured.36
Signs of Virilization
Weight Changes
Abdominal and Pelvic Examination
Weight gain and distribution need to be assessed. Central obesity is seen in patients with Cushing’s syndrome. Obese women with PCOS have a greater prevalence (73% vs. 56%) of hirsutism compared to nonobese women with PCOS.85 Obesity tends to enhance the androgenic state by two mechanisms:29 (1) the resultant insulin resistance and hyperinsulinemia leads to lowered hepatic SHBG production, in turn resulting in increased levels of free testosterone, and (2) the activation of androgenic precursors in the peripheral tissues is enhanced.
Presence of a neoplasm may be suggested by a mass palpable either in the abdominal area or in the pelvic region. Clitorimegaly can be defined by a clitoral index (length × width) of greater than 35 mm2 or a length greater than 10 mm.87
Deepening of the voice and changes in muscle mass and distribution may be observed. Loss of breast tissue and subcutaneous fat may lead to loss of the normal female body contour in some women.
DIAGNOSTIC TESTS Usually a few serum hormone determinations is all that is required to arrive at a diagnosis. However, under certain clinical circumstances dynamic endocrine testing and special imaging is required.
Family History
An increased prevalence of hirsutism, acne, and male-pattern balding has been observed in relatives of hirsute women.10 Among families of women diagnosed with PCOS, an autosomal dominant pattern of inheritance has been reported for the inheritance of polycystic ovaries and premature male-pattern balding.86 Whether this familial clustering is due to the genetic pattern of the underlying disorder or to some other factor is still unclear. Ethnicity
Ethnic differences in hair quantity and distribution need to be kept in mind. Clearly, the criteria for assessing hirsutism among women of different racial background need to be adjusted and individualized (see Table 18-2). Drug History
Anabolic steroids such as testosterone and danazol can cause hirsutism. The other classes of drugs that can be associated with hirsutism are those that elevate prolactin, such as the phenothiazines (e.g., chlorpromazine), gastrointestinal motility drugs (e.g., metoclopramide), and some antihypertensive medications (e.g., methyldopa).
Physical Examination
Laboratory Tests Testosterone
Measurement of total and/or free testosterone is useful in the evaluation of any state of androgen excess. Although there have been considerable improvements in the commercially available assays for measuring total serum testosterone, there is still a wide degree of between-kit variability, especially in samples from women.88 It is important to keep in mind that an accurate measurement of free testosterone is highly dependent on an accurate assay for total testosterone.89,90 Consequently, it is important for a clinician to be familiar with the assay used and the normal ranges in the laboratory. Total testosterone value above 200 ng/dL has been suggested to signify an androgen-secreting neoplasm.91 However, in a more recent review, Friedman and colleagues92 followed 18 women with serum testosterone level greater than 200 ng/dL (7 nmol/L) for 5 years. Only two women were diagnosed with an androgen-secreting neoplasm. Most of the women were overweight. Conversely, if virilization is present even in the setting of only a modest elevation in serum testosterone, then further workup is warranted. It remains possible that small neoplasms are not being detected by conventional means (i.e., computed tomography [CT] scan of adrenal glands, transvaginal ultrasound of the ovaries).
Skin
268
A thorough examination of androgen-sensitive areas is warranted when evaluating a woman with concerns regarding hirsutism. Hirsutism needs to be differentiated from hypertrichosis. The latter is manifested by increased vellus hair over the whole body. The conditions causing hypertrichosis have been mentioned previously. Noting the sites involved and the severity of involvement will allow the physician to document response to therapy. Acanthosis nigricans is a hyperpigmented, velvety reactive skin change often associated with insulin resistance. It is usually found in flexural areas such as the posterior neck, axillae, and inguinal regions. In cases of rapid development of acanthosis nigricans, an occult malignancy (most commonly gastrointestinal or pulmonary) needs to be sought. Plethora, telangiectasia, and violaceous abdominal striae are characteristic skin findings in Cushing’s syndrome. Acne and androgenic alopecia may also be present.
Dehydroepiandrosterone Sulfate
Dehyroepiandrosterone sulfate is primarily produced by the adrenal glands; hence, it is a good marker for adrenal androgen production. Although a weak androgen, its main importance in androgen excess states is to provide a pool of precursor for testosterone formation in the periphery. It is frequently elevated in anovulatory women.93 Levels decline with age but with marked individual variability.94 DHEAS values greater than 700 μg/dL (24.3 μmol/L) are suggestive of a virilizing adrenal tumor.4 Testing for Congenital Adrenal Hyperplasia
As previously mentioned, most cases of CAH are due to 21-hydroxylase deficiency. Nonclassic 21-OHD is often clinically indistinguishable from PCOS. An unstimulated early-morning follicular phase 17-hydroxyprogesterone determination has been recommended as a screening tool for this condition because a value
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Chapter 18 Hirsutism of less than 2 ng/dL has been shown to have a negative predictive value of 100%.95 Patients who have 17-hydroxyprogesterone levels greater than or equal to 2 ng/dL should proceed to a corticotropin stimulation test. Measuring 17-hydroxyprogesterone level at baseline and 60 minutes after an intravenous injection of 250 μg of synthetic corticotropin is used to establish the diagnosis of late-onset 21-hydroxylase deficiency Post-stimulation values greater than 10 ng/mL (30.3 nmol/L) constitute a positive test.66 Testing for Cushing’s Syndrome
In those hirsute women with other clinical signs suggestive of hypercortisolism, screening for Cushing’s syndrome is warranted. A 24-hour urine free cortisol is widely used to establish the presence of Cushing’s syndrome. The concomitant measurement of creatinine in the urine sample ensures the adequacy of the collection. Sensitivity ranging from 95% to 100% and specificity from 94% to 98% has been cited by other authors.97 Other screening tests include low-dose (1 mg) overnight dexamethasone suppression testing, midnight serum cortisol, and midnight salivary cortisol. To date, there is no specific protocol advocated or one test shown as being clearly superior to the others in confirming the diagnosis of Cushing’s syndrome. Most clinicians will use a combination of these tests. Once the diagnosis is confirmed, additional tests are required to establish the specific etiology of Cushing’s syndrome. Referral to a center that deals with such patients is usually recommended. Hyperprolactinemia
Hyperprolactinemia has been associated with hirsutism. Consequently, a serum prolactin level should be measured in the workup for hirsutism, particularly in those hirsute women with irregular menstrual cycles. A review of the patient’s medications is warranted to rule these out. Elevated prolactin level may also be seen in association with untreated hypothyroidism as a cause of the hyperprolactinemia warranting a screening thyrotropin test as well. Magnetic resonance imaging of the hypothalamicpituitary region may be warranted. Serum Luteinizing Hormone and Follicle-Stimulating Hormone
Measurements of serum LH and follicle-stimulating hormone (FSH) are of little clinical utility in most cases of hirsutism. A disproportionate increase in serum LH as compared to FSH has been observed frequently in women with PCOS.97 A LH:FSH ratio of greater than 3 has been used by some to indicate PCOS; however, a ratio lesss than 3 does not exclude the diagnosis. Women with irregular or absent menses suspected of ovarian failure are an exception to this principle. In these women, measurement of serum FSH is important to exclude ovarian failure.
Imaging Studies Ultrasonography
The diagnosis of PCOS is often established on clinical grounds with minimal supportive laboratory data. Polycystic ovaries using ultrasonography are not found in all women with PCOS; conversely, as many as 20% to 25% of normal women may have polycystic ovaries on ultrasound. Some women with CAH and adrenal tumors may also have polycystic ovaries. Hence, ultrasound is most often utilized when an ovarian neoplasm is suspected. The positive predictive value of ultrasound for adnexal
malignancy is cited to be 73%, with a negative predictive value of 91%.98 Transvaginal ultrasonography is the preferred method of imaging the ovary with the principal aim of lateralizing the lesion. Adrenal Imaging
Due to the rarity of androgen-secreting adrenal tumors, adrenal imaging is not indicated unless there is a strong suspicion for an adrenal neoplasm. Incidental adrenal masses (“incidentalomas”) are found in 1% to 4% of abdominal imaging studies of patients without suspected adrenal pathology.99 In postmortem autopsies, incidental adrenal masses are seen in up to 8.7% of unselected populations.100 If clinically indicated CT or MRI are quite sensitive for detecting adrenal tumors. Ovarian and Adrenal Venous Sampling
In cases in which adrenal and ovarian imaging fail to identify a source for excessive androgen levels, biochemical analysis of blood samples from the adrenal and ovarian veins have been advocated by some authors.101 However, use of this technique should be restricted to centers experienced in its use.102
MANAGEMENT Treatment of hirsutism is directed toward the underlying etiology. It also needs to be tailored to the patient’s goal for therapy. Often a combination of mechanical therapy targeting local manifestations of hirsutism and pharmacologic therapy aimed toward the underlying cause are used. Treatment options can be broadly divided into (1) mechanical/local removal of unwanted hair, (2) androgen suppression, and (3) blockade of peripheral androgen action. Before beginning treatment, it is important to inform the patient that improvement in hair growth may not be noticeable for at least 6 months due to the intrinsically long half-life of the hair follicle. Beyond the directed therapy for hirsutism, the management of a hirsute patient should also consider the consequences of chronic anovulation and the increased cardiovascular risk from possible insulin resistance. Chronic anovulation is associated with endometrial hyperplasia or carcinoma as well as dysfunctional uterine bleeding. Insulin resistance associated with most cases of PCOS increases the risk for development of type 2 diabetes mellitus, hypertension, dyslipidemia, and coronary artery disease. Consequently, diet, exercise and a weight loss program need to be incorporated into the treatment plan for women with PCOS.
Hair Removal Nonpharmacologic measures of hair removal include waxing, shaving, plucking, bleaching, and use of depilatory creams as well as electrosurgical methods such as electrolysis and laser therapy. Most of these methods are effective transiently; none treats the underlying etiology. Shaving, epilation (plucking and waxing), chemical depilation, and bleaching are all safe, easy, and inexpensive. Shaving is not popular among women for facial hair removal because of the unsightly stubble that occurs once regrowth occurs. Mild skin irritation either due to local trauma or to chemical reaction may occur with any of these methods.103,104 Hair removal is achieved in electrolysis by delivering an electric current to the hair follicle using a probe. This is a slow,
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Section 3 Adult Reproductive Endocrinology expensive, and often painful process. Scarring, as well as hypopigmetnation and hyperpigmentation, have been reported to occur.105 Laser Hair Removal
Laser hair removal targets the melanin in the hair bulb.103 It is based on the principle that selective thermal injury is achieved only in the target capable of absorbing the specific wavelength used for a given amount of time.106 Only hair in the anagen phase is susceptible to injury from the lasers. Different lasers are available, such as the ruby, alexandrite, diodide, and neodymium;yttrium-aluminum-garnet (Nd:YAG) lasers. These appear to be equally efficacious.105 More studies with longer follow-up are needed to be able to define their role conclusively. Topical Agents Eflornithine
Eflornithine (Vaniqa) is a topical agent that inhibits ornithine decarboxylase—a rate-limiting enzyme in the biosynthesis of polyamines.104 Reduction in hair growth rates have been reported in 32% of patients who used this product as compared to placebo.4 Its effects may last up to 8 weeks after the therapy is discontinued.103 Side effects reported include stinging, tingling, and rash.
Androgen Suppression Oral Contraceptive Pills
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Like gonadotropin-releasing hormone (GnRH) analogs, exogenous estrogen and progesterone in oral contraceptives inhibit gonadotropin secretion, leading to decreased ovarian androgen production. In addition, oral contraceptives have also been shown to increase SHBG levels and to decrease adrenal production of androgens and their precursors.107–109 All of these make oral contraceptives ideal for use in hirsute women with hyperandrogenism. In general, 60% to 100% of hirsute women show improvement with oral contraceptive use. Currently, low-dose estrogen formulations in almost all the oral contraceptives available in the United States have circumvented the adverse effects associated with high estrogen content while demonstrating comparable reduction in androgen level and improvement in hair growth.110 However, there are differences in the oral progestins available. Not all oral progestins are purely progestational, and most of these have been shown to have androgenic activity.79 In the older oral contraceptive pills, lowering the progestin dose minimized its androgenic side effects. Currently, newer progestins with improved progesterone-receptor selectivity are available. These include norgestimate, desogestrel, and gestodene.111 Oral contraceptives formulations containing these newer progestins have been shown to be efficacious in the treatment of hirsutism.112,113 Drosperinone is a new progestin contained in one oral contraceptive pill as well as in an agent used for hormone replacement therapy. It is an analog of spironolactone that has both anti-mineralocorticoid and progestogenic properties. In most hirsute women treated with 30 μg ethinyl estradiol plus 3 mg drosperinone for 12 cycles, hirsutism scores improved from the sixth cycle onward.114 However, no direct comparative trials with other oral contraceptive pills have been reported.
Gonadotropin-releasing Hormone Agonists
GnRH is a hypothalamic decapeptide hormone released in a pulsatile fashion and regulates the production and release of both LH and FSH from the anterior pituitary gland.115 GnRH and its agonists have been used either to stimulate the pituitary-gonadal axis (an acute event) or to down-regulate the GnRH receptor by continuous exposure, leading to gonadotropin/gonadal suppression (chemical castration).116,117 Several studies have shown the efficacy of using GnRH agonists in the treatment of hirsutism.118 Treatment of hirsute women with nafarelin for 6 months results in significant decreases in serum gonadotropin, testosterone, free testosterone, and androstenedione levels, as well as significant decreases in hirsutism scores.119 However, cost of therapy and clinical consequences of hypoestrogenism—such as hot flashes and decreased bone mineral density—limit its usefulness. Currently, their use is not recommended for first-line therapy of hirsutism. Combination of GnRH agonists with estrogen therapy has ameliorated the side effects from hypoestrogenism. In a comparative study of leuprolide plus estrogen versus an oral contraceptive pill for the treatment of hirsutism, the combination of leuprolide plus estrogen demonstrated a more rapid improvement in hirsutism.120 Glucocorticoids
Glucocorticoid treatment lowers adrenal androgen production. However, its efficacy in treating hirsutism is limited. Low doses need to be used to avoid side effects such as weight gain, osteoporosis, glucose intolerance, and adrenal suppression. Even in women with late-onset CAH, the results of treating hirsutism with glucocorticoids are often disappointing. In a comparative study of cyproterone acetate versus hydrocortisone in treating hirsutism in women with this condition,121 a 54% reduction in hirsutism score was noted in cyproterone acetate-treated patients versus a 26% reduction noted in the hydrocortisone group after 1 year. However, hydrocortisone has a shorter halflife as compared to prednisone or dexamethasone, which may have accounted for these results. The latter two agents are preferred in this condition. The commonly used dosage for prednisone is 2.5 mg twice a day, whereas for dexamethasone, it is 0.125–0.25 mg at bedtime. Higher doses are not recommended. Insulin Sensitizers
Insulin resistance, with its consequent hyperinsulinemia, plays an important role in the pathogenesis of PCOS. Hyperinsulinemia has been shown to increase ovarian androgen production122,123 and to decrease the production of SHBG.56 Dietary weight loss in obese women with PCOS has been shown to improve insulin resistance and reduce hyperandrogenism with consequent decreased hirsutism and improved ovulation, and fertility rates.124,125 On the other hand, metformin is an effective treatment for anovulation in women with PCOS.126 Metformin is a biguanide that lowers glucose in the presence of insulin by reducing hepatic gluconeogenesis and increasing peripheral cellular glucose uptake.127 Metformin also reduces levels of free testosterone, which has been attributed to increased SHBG levels rather than decreased total serum testosterone levels.128–130 There is also the question of whether it is the weight loss from the anorectic effects of metformin rather than an independent effect of metformin that leads to improvement in free testosterone levels.131
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Chapter 18 Hirsutism Metformin has been shown to improve hirsutism in several but not all studies.131–134 In a 12-month study comparing metformin with ethinyl estradiol/cyproterone acetate, metformin resulted in a greater reduction in the hirsutism score.135 In another study, the opposite was observed.136 Currently, the use of metformin in doses between 1.5 and 2.0 g/day is recommended to ameliorate hirsutism in the PCOS population.135,137 Thiazolidinedione compounds comprise another class of insulin-sensitizing drugs, which are selective ligands of the nuclear transcription factor peroxisome-proliferator-activated-receptor γ (PPARγ). These enhance glucose uptake mainly in adipose and muscle tissues. Two drugs are currently available—rosiglitazone and pioglitazone. The Food and Drug Administration (FDA) withdrew troglitazone, the first available thiazolidinedione, from the market in 1999 because of hepatotoxicity. Earlier studies done using troglitazone in PCOS demonstrated significant reductions in mean serum free testosterone levels, improvement in ovulatory frequency, and improvement in hirsutism scores.138–140 Similarly, small studies using rosiglitazone or pioglitazone showed improved ovulatory rates and insulin sensitivity.141–144 Results of hormonal assessments were variable but only two studies using pioglitazone alone and in combination with metformin showed an increase in SHBG levels.143,145 Overall, measures to improve insulin resistance are important in the management of hirsute women with underlying PCOS. However, one should keep in mind that metformin is in pregnancy category B (drugs that have been used during human pregnancy and do not appear to cause major birth defects or those in which animal studies show no risk), whereas rosiglitazone and pioglitazone are category C (drugs that are either more likely to cause problems to the mother or fetus or are still lacking human data). Consequently, current use of thiazolidinediones in women desirous of pregnancy is not recommended.
Peripheral Androgen Blockade Blocking the binding of testosterone and dihydrotestosterone to the androgen receptor is an effective way of treating hirsutism. Currently, there are several medications included in this class. However, all have teratogenic potential and should be used in conjunction with adequate contraception in women of childbearing age. Spironolactone
The aldosterone antagonist spironolactone also competes with testosterone and dihydrotestosterone for the androgen receptor. Spironolactone (50 to 200 mg/day) will reduce the quantity and quality of facial hair growth in the majority of women with moderate to severe hirsutism.146 The maximal effect is noted by 6 months and maintained at 12 months of treatment. It was equally effective in treating hirsutism in women with either idiopathic or PCOS-related hirsutism. Reduction in ovarian androgen production was observed, whereas it had no effect on adrenal androgen or cortisol levels. Diuresis was limited to the first few days of treatment. A similar reduction in total testosterone has been demonstrated in doses of 100 mg/day to 200 mg/day of spironolactone.147 Anagen hair shaft diameters decreased in both groups (19% and 30%, respectively). Although no direct comparative trial with an oral contraceptive and spironolactone is available,
combination therapy has been shown to significantly improve hirsutism and reduce serum total and free testosterone levels.148 Furthermore, the addition of an oral contraceptive will decrease the frequency one of the side effects of spironolactone that could decrease compliance: irregular menstrual cycles. Side effects commonly associated with spironolactone include gastrointestinal discomfort, polyuria, nocturia, fatigue, headaches, irregular menstrual bleeding, decreased libido, and atopic reactions.24 Hyperkalemia is uncommon in women with normal renal function. Flutamide
An agent used for the hormonal treatment of prostate cancer, flutamide is effective in the treatment of hirsutism.149 In a study of 18 hirsute women treated with flutamide 125 mg three times a day for 12 months,150 hirsutism scores were markedly improved in all women, with concomitant reduction in serum androgen levels. It is also more effective than spironolactone in treating hirsutism, with reduction in hirsutism scores to almost normal after 6 months of therapy with flutamide versus only a 30% reduction in women treated with spironolactone.151 Major concerns include the expense and rare hepatotoxicity, which can sometimes be fatal.152 Consequently, its use for hirsutism is currently off-label; it is not approved for this use by the FDA. Cyproterone Acetate
Cyproterone acetate is an antiandrogen as well as a progestin. It is used as a part of an oral contraceptive or added to an estrogen or an oral contraceptive pill.153 It reduces circulating testosterone and androstenedione levels by suppressing LH.7 In the periphery, it inhibits androgen binding to its receptor.121 In a prospective, randomized trial comparing low dose flutamide, finasteride, ketoconazole, and cyproterone acetate–estrogen in treating hirsutism, cyproterone acetate–estrogen and flutamide were noted to be the most efficacious.154 The cyproterone acetate–estrogen combination reduced hair growth most rapidly. However, cases of fatal hepatitis have also been reported in association with use of cyproterone acetate. Currently, it is not available in the United States. Finasteride
Finasteride is an inhibitor of type 2 5α-reductase and is currently approved for the treatment of benign prostatic hyperplasia.155 It has also been approved for the treatment of androgenic alopecia in men at a dose of 1 mg/day. In a study of 27 women with idiopathic hirsutism,156 treatment with finasteride 5 mg/day alone or in combination with an oral contraceptive for 6 months showed significant improvement in clinical hirsutism scores. No change in serum androgen levels was noted in the finasteride only group. However, the group that received combination therapy showed decreased dihydrotestosterone levels. Finasteride treatment appears to be as effective as spironolactone in treating hirsutism.157 In a prospective study comparing low-dose flutamide, finasteride, ketoconazole, and cyproterone acetate–estrogen regimens, improvement in hirsutism scores was smaller in the group receiving finasteride.154,157 That group was also slowest in decreasing hair growth rate. However, it was the best tolerated among the four regimens. The FDA has not approved finasteride for use in hirsutism.
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Hirsutism is a common reason for women to seek medical attention. Most often, it results from conditions that are benign. The history and physical examination will often provide the clinician enough clues as to the possible underlying etiology. Simple screening tests using serum total and/or free testosterone, DHEAS, and follicular-phase 17-hydroxyprogesterone will direct the clinician as to the most likely etiology. In women with associated oligomenorrhea and/or infertility, a serum prolactin and thyrotropin level should be assessed as well. Most women with hirsutism have PCOS. With the recognition of the increased risk for the development of diabetes, hypertension, and hyperlipidemia in this population, an increased surveillance for the detection of any of these conditions is warranted. Ultimately, the patient’s goal for the consultation must direct the therapy as well. In some women, simple reassurance of the benign nature of this condition may be enough. In others, a combination of mechanical methods and pharmacologic agents may be needed. Whatever the treatment option chosen, it must be emphasized that noticeable improvement in hair growth occurs slowly.
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PEARLS ●
In women, direct secretion from the ovaries and the adrenal glands accounts for 30% to 50% of circulating testosterone. The rest arises from peripheral conversion of androgen precursors.
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Approximately 98% to 99% of plasma testosterone is protein bound—with higher affinity to SHBG. Androgens, insulin, and growth hormone lower SHBG levels, whereas estrogens and thyroid hormone excess result in increased SHBG levels. Rapid progression of hirsutism associated with virilization is suggestive of an androgen-secreting neoplasm of the ovary or the adrenal gland. Regular menses do not predict normal androgen status in hirsute women. PCOS is responsible for most cases of hirsutism. Androgen-secreting neoplasms are uncommon and usually present with new onset of symptoms that are rapidly progressive. Serum testosterone >200 ng/dL (7 nmol/L) and DHEAS values greater than 700 μg/dL (24.3 μmol/L) are suggestive but not diagnostic of a tumor. Most patients with these serum levels will not have tumors. An unstimulated early-morning follicular phase 17-hydroxyprogesterone determination is recommended as a screening tool for CAH; a value of <2 ng/dL has been shown to have a negative predictive value of 100%. Mechanical hair removing techniques and oral contraceptives are the main approaches to treatment. Spironolactone is an effective treatment for hirsutism. All other peripheral antiandrogens have significant limitations. Since all antiandrogens are potentially teratogenic, adequate concomitant contraception is required.
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80. Bates GW, Cornwell CE: Iatrogenic causes of hirsutism. Clin Obstet Gynecol 34:848–851, 1991. 81. Redmond G.P: Androgenic disorders of women: Diagnostic and therapeutic decision making. Am J Med 98:120S–129S, 1995. 82. Spark RF: Dehydroepiandrosterone: A springboard hormone for female sexuality. Fertil Steril 77(Suppl 4):S19–S25, 2002. 83. Cela E, et al: Prevalence of polycystic ovaries in women with androgenic alopecia. Eur J Endocrinol 149:439–442, 2003. 84. Mehta A, et al: Should androgen levels be measured in hirsute women with normal menstrual cycles? Int J Fertil 37:354–357, 1992. 85. Kiddy DS, et al: Differences in clinical and endocrine features between obese and non-obese subjects with polycystic ovary syndrome: An analysis of 263 consecutive cases. Clin Endocrinol (Oxf) 32:213–220, 1990. 86. Govind A, Obhrai MS, Clayton RN: Polycystic ovaries are inherited as an autosomal dominant trait: Analysis of 29 polycystic ovary syndrome and 10 control families. J Clin Endocrinol Metab 84:38–43, 1999. 87. Tafaro E, et al: Importance of serum androgens chromatography on the ACTH stimulated adrenal steroidogenesis evaluation in hirsute women. Boll Soc Ital Biol Sper 59:1877–1882, 1983. 88. Boots LR, et al: Measurement of total serum testosterone levels using commercially available kits: High degree of between-kit variability. Fertil Steril 69:286–292, 1998. 89. Miller KK, et al: Measurement of free testosterone in normal women and women with androgen deficiency: comparison of methods. J Clin Endocrinol Metab 89:525–533, 2004. 90. Matsumoto AM, Bremner WJ: Serum testosterone assays—accuracy matters. J Clin Endocrinol Metab 89:520–524, 2004. 91. Meldrum, DR, Abraham GE: Peripheral and ovarian venous concentrations of various steroid hormones in virilizing ovarian tumors. Obstet Gynecol 53:36–43, 1979. 92. Friedman CI, et al: Serum testosterone concentrations in the evaluation of androgen-producing tumors. Am J Obstet Gynecol 153:44–49, 1985. 93. Hoffman DI, Klove K, Lobo RA: The prevalence and significance of elevated dehydroepiandrosterone sulfate levels in anovulatory women. Fertil Steril 42:76–81, 1984. 94. Tannenbaum C, et al: A longitudinal study of dehydroepiandrosterone sulphate (DHEAS) change in older men and women: The Rancho Bernardo Study. Eur J Endocrinol 151:717–725, 2004. 95. Azziz R, Zacur HA: 21-Hydroxylase deficiency in female hyperandrogenism: Screening and diagnosis. J Clin Endocrinol Metab 69:577–584, 1989. 96. Boscaro M, Barzon L, Sonino N: The diagnosis of Cushing’s syndrome: Atypical presentations and laboratory shortcomings. Arch Intern Med 160:3045–3053, 2000. 97. Waldstreicher J, et al: Hyperfunction of the hypothalamic-pituitary axis in women with polycystic ovarian disease: Indirect evidence for partial gonadotroph desensitization. J Clin Endocrinol Metab 66:165–172, 1988. 98. Benacerraf BR, et al: Sonographic accuracy in the diagnosis of ovarian masses. J Reprod Med 35:491–495, 1990. 99. Duh QY: Adrenal incidentalomas. Br J Surg 89:1347–1349, 2002. 100. Hamrahian AH, et al: Clinical utility of noncontrast computed tomography attenuation value (hounsfield units) to differentiate adrenal adenomas/hyperplasias from nonadenomas: Cleveland Clinic experience. J Clin Endocrinol Metab 90:871–877, 2005. 101. Moltz L, et al: Ovarian and adrenal vein steroids in seven patients with androgen-secreting ovarian neoplasms: Selective catheterization findings. Fertil Steril 42:585–593, 1984. 102. Kaltsas GA, et al: Is ovarian and adrenal venous catheterization and sampling helpful in the investigation of hyperandrogenic women? Clin Endocrinol 59:34–43, 2003. 103. Shenenberger DW, Utecht LM: Removal of unwanted facial hair. Am Fam Phys 66:1907–1911, 2002. 104. Ramos-e-Silva M, de Castro MC, Carneiro Jr LV: Hair removal. Clin Dermatol 19:437–444, 2001. 105. Lanigan SW: Management of unwanted hair in females. Clin Exp Dermatol 26:644–647, 2001.
106. DiBernardo BE, et al: Laser hair removal: Where are we now? Plastic Reconstruct Surg 104:247–258, 1999. 107. Givens JR, et al: The effectiveness of two oral contraceptives in suppressing plasma androstenedione, testosterone, LH, and FSH, and in stimulating plasma testosterone-binding capacity in hirsute women. Am J Obstet Gynecol 124:333–339, 1976. 108. Fern M, Rose DP, Fern EB: Effect of oral contraceptives on plasma androgenic steroids and their precursors. Obstet Gynecol 51:541–544, 1978. 109. Madden JD, et al: The effect of oral contraceptive treatment on the serum concentration of dehydroisoandrosterone sulfate. Am J Obstet Gynecol 132:380–384, 1978. 110. Raj SG, et al: Normalization of testosterone levels using a low estrogen-containing oral contraceptive in women with polycystic ovary syndrome. Obstet Gynecol 60:15–19, 1982. 111. Bringer J: Norgestimate: A clinical overview of a new progestin. Am J Obstet Gynecol 166:1969–1977, 1992. 112. Dewis P, et al: The treatment of hirsutism with a combination of desogestrel and ethinyl oestradiol. Clin Endocrinol (Oxf) 22:29–36, 1985. 113. Volpe A, et al: Efficacy on hyperandrogenism and safety of a new oral contraceptive biphasic formulation containing desogestrel. Eur J Obstet Gynecol Reprod Biol 53:205–209, 1994. 114. Guido M, et al: Drospirenone for the treatment of hirsute women with polycystic ovary syndrome: A clinical, endocrinological, metabolic pilot study. J Clin Endocrinol Metab 89:2817–2823, 2004. 115. Henzl MR: Gonadotropin-releasing hormone and its analogues: From laboratory to bedside. Clin Obstet Gynecol 36:617–635, 1993. 116. Rittmaster RS: Use of gonadotropin-releasing hormone agonists in the treatment of hyperandrogenism. Clin Obstet Gynecol 36:679–689, 1993. 117. Chang RJ, et al: Steroid secretion in polycystic ovarian disease after ovarian suppression by a long-acting gonadotropin-releasing hormone agonist. J Clin Endocrinol Metab 56:897–903, 1983. 118. Rittmaster RS, Thompson DL: Effect of leuprolide and dexamethasone on hair growth and hormone levels in hirsute women: The relative importance of the ovary and the adrenal in the pathogenesis of hirsutism. J Clin Endocrinol Metab 70:1096–1102, 1990. 119. Andreyko JL, Monroe SE, Jaffe RB: Treatment of hirsutism with a gonadotropin-releasing hormone agonist (nafarelin). J Clin Endocrinol Metab 63:854–859, 1986. 120. Azziz R, et al: Leuprolide and estrogen versus oral contraceptive pills for the treatment of hirsutism: A prospective randomized study. J Clin Endocrinol Metab 80:3406–3411, 1995. 121. Spritzer P, et al: Cyproterone acetate versus hydrocortisone treatment in late-onset adrenal hyperplasia. J Clin Endocrinol Metab 70:642–646, 1990. 122. Barbieri RL, Makris A, Ryan KJ: Effects of insulin on steroidogenesis in cultured porcine ovarian theca. Fertil Steril 40:237–241, 1983. 123. Erickson GF, et al: The ovarian androgen producing cells: A review of structure/function relationships. Endocrine Rev 6:371–399, 1985. 124. Pasquali R, et al: Clinical and hormonal characteristics of obese amenorrheic hyperandrogenic women before and after weight loss. J Clin Endocrinol Metab 68:173–179, 1989. 125. Jakubowicz DJ, Nestler JE: 17 α-Hydroxyprogesterone responses to leuprolide and serum androgens in obese women with and without polycystic ovary syndrome offer dietary weight loss. J Clin Endocrinol Metab 82:556–560, 1997. 126. McCarthy EA, et al: Metformin in obstetric and gynecologic practice: A review. Obstet Gynecol Surv 59:118–127, 2004. 127. Moghetti, P, et al: Metformin effects on clinical features, endocrine and metabolic profiles, and insulin sensitivity in polycystic ovary syndrome: A randomized, double-blind, placebo-controlled 6-month trial, followed by open, long-term clinical evaluation. J Clin Endocrinol Metab 85:139–146, 2000. 128. Lord JM, Flight IH, Norman RJ: Metformin in polycystic ovary syndrome: Systematic review and meta-analysis. BMJ 327:951–953, 2003.
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Chapter 18 Hirsutism 129. Nestler JE, Jakubowicz DJ: Decreases in ovarian cytochrome P450c17 α activity and serum free testosterone after reduction of insulin secretion in polycystic ovary syndrome. NEJM 335:617–623, 1996. 130. Vandermolen DT, et al: Metformin increases the ovulatory rate and pregnancy rate from clomiphene citrate in patients with polycystic ovary syndrome who are resistant to clomiphene citrate alone. Fertil Steril 75:310–315, 2001. 131. Ehrmann DA, et al: Effects of metformin on insulin secretion, insulin action, and ovarian steroidogenesis in women with polycystic ovary syndrome. J Clin Endocrinol Metab 82:524–530, 1997. 132. Pasquali R, et al: Effect of long-term treatment with metformin added to hypocaloric diet on body composition, fat distribution, and androgen and insulin levels in abdominally obese women with and without the polycystic ovary syndrome. J Clin Endocrinol Metab 85:2767–2774, 2000. 133. Ibanez L, et al: Sensitization to insulin in adolescent girls to normalize hirsutism, hyperandrogenism, oligomenorrhea, dyslipidemia, and hyperinsulinism after precocious pubarche. J Clin Endocrinol Metab 85:3526–3530, 2000. 134. Sturrock ND, Lannon B, Fay TN: Metformin does not enhance ovulation induction in clomiphene resistant polycystic ovary syndrome in clinical practice. Br J Clin Pharmacol 53:469–473, 2002. 135. Harborne L, et al: Metformin or antiandrogen in the treatment of hirsutism in polycystic ovary syndrome. J Clin Endocrinol Metab 88:4116–4123, 2003. 136. Morin-Papunen LC, et al: Endocrine and metabolic effects of metformin versus ethinyl estradiol–cyproterone acetate in obese women with polycystic ovary syndrome: A randomized study. J Clin Endocrinol Metab 85:3161–3168, 2000. 137. Kelly CJ, Gordon D: The effect of metformin on hirsutism in polycystic ovary syndrome. Eur J Endocrinol 147:217–221, 2002. 138. Dunaif A, et al: The insulin-sensitizing agent troglitazone improves metabolic and reproductive abnormalities in the polycystic ovary syndrome. J Clin Endocrinol Metab 81:3299–3306, 1996. 139. Ehrmann DA, et al: Troglitazone improves defects in insulin action, insulin secretion, ovarian steroidogenesis, and fibrinolysis in women with polycystic ovary syndrome. J Clin Endocrinol Metab 82:2108–2116, 1997. 140. Azziz R, et al: Troglitazone improves ovulation and hirsutism in the polycystic ovary syndrome: a multicenter, double blind, placebocontrolled trial. J Clin Endocrinol Metab 86:1626–1632, 2001. 141. Ghazeeri G, et al: Effect of rosiglitazone on spontaneous and clomiphene citrate-induced ovulation in women with polycystic ovary syndrome. Fertil Steril 79:562–566, 2003. 142. Belli SH, et al: Effect of rosiglitazone on insulin resistance, growth factors, and reproductive disturbances in women with polycystic ovary syndrome. Fertil Steril 81:624–629, 2004. 143. Brettenthaler N, et al: Effect of the insulin sensitizer pioglitazone on insulin resistance, hyperandrogenism, and ovulatory dysfunction
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in women with polycystic ovary syndrome. J Clin Endocrinol Metab 89:3835–3840, 2004. Romualdi D, et al: Selective effects of pioglitazone on insulin and androgen abnormalities in normo- and hyperinsulinaemic obese patients with polycystic ovary syndrome. Hum Reprod 18:1210–1218, 2003. Glueck CJ, et al: Pioglitazone and metformin in obese women with polycystic ovary syndrome not optimally responsive to metformin. Hum Reprod 18:1618–1625, 2003. Cumming DC, et al: Treatment of hirsutism with spironolactone. JAMA 247:1295–1298, 1982. Lobo RA, et al: The effects of two doses of spironolactone on serum androgens and anagen hair in hirsute women. Fertil Steril 43:200–205, 1985. Board JA, Rosenberg SM, Smeltzer JS: Spironolactone and estrogen–progestin therapy for hirsutism. South Med J 80:483–486, 1987. Ciotta L, et al: Treatment of hirsutism with flutamide and a low-dosage oral contraceptive in polycystic ovarian disease patients. Fertil Steril 62:1129–1135, 1994. Moghetti P, et al: Flutamide in the treatment of hirsutism: Long-term clinical effects, endocrine changes, and androgen receptor behavior. Fertil Steril 64:511–517, 1995. Cusan L, et al: Comparison of flutamide and spironolactone in the treatment of hirsutism: A randomized controlled trial. Fertil Steril 61:281–287, 1994. Wysowski DK, et al: Fatal and nonfatal hepatotoxicity associated with flutamide. Ann Intern Med 118:860–864, 1993. Rittmaster RS: Hirsutism. Lancet 349:191–195, 1997. Venturoli S, et al: A prospective randomized trial comparing low dose flutamide, finasteride, ketoconazole, and cyproterone acetate–estrogen regimens in the treatment of hirsutism. J Clin Endocrinol Metab 84:1304–1310, 1999. Rittmaster RS: Finasteride. NEJM 330:120–125, 1994. Faloia E, et al: Effect of finasteride in idiopathic hirsutism. J Endocrinol Invest 21:694–698, 1998. Wong IL, et al: A prospective randomized trial comparing finasteride to spironolactone in the treatment of hirsute women. J Clin Endocrinol Metab 80:233–238, 1995. Knochenhauer ES, Key TJ, Kahsar-Miller M, et al: Prevalence of the polycystic ovary syndrome in unselected black and white women of the southeastern United States: A prospective study. J Clin Endocrinol Metab 83:3078–3082, 1998. Asuncion M, Calco RM, San Millan JL, et al: A prospective study of the prevalence of the polycystic ovary syndrome in unselected Caucasian women from Spain. J Clin Endocrinol Metab 85:2434–2438, 2000. Zargar AH, Wani AI, Masoodi SR, et al: Epidemiologic and etiologic aspects of hirsutism in Kashmiri women in the Indian subcontinent. Fertil Steril 77:674–678, 2002.
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19
Anovulation and Ovulatory Dysfunction Margo Fluker and Stephanie Fisher
INTRODUCTION
directed toward potential dysfunction in the three components of the hypothalamic-pituitary-ovarian (HPO) axis.
Anovulation and ovulatory dysfunction are frequent reasons for gynecologic referral. The most common form of ovulatory dysfunction, polycystic ovary syndrome (PCOS), is estimated to occur in up to 6% to 10% of women.1 Ovulatory dysfunction may result in a spectrum of clinical symptoms ranging from amenorrhea to frequent, irregular, and heavy menses. In addition to menstrual irregularities, many women will experience subfertility or other endocrine symptoms, such as hirsutism. Choice of therapy will depend on numerous factors, including the presenting symptom, age, desire for fertility, and associated conditions. Regardless of the etiology, a spectrum of ovulatory disorders exists that may precede the eventual development of amenorrhea or occur during the recovery from amenorrhea (Fig. 19-1). Underlying abnormalities in ovulatory function may present clinically with either quantitative or qualitative changes in the menstrual cycle. A prolonged follicular phase or intermittent anovulation both result in infrequent (cycles greater than 35 days) and often heavy menstrual flow; a shortened follicular or luteal phase is associated with frequent menstrual flow and often premenstrual spotting. Because ovulatory disorders encompass a spectrum of clinical presentations and a variety of underlying etiologies, this chapter necessarily overlaps with other chapters that focus on specific endocrine abnormalities. The current chapter is not intended to be an in-depth review of each of these associated topics, but rather a brief overview to help understand how they are related to the pathophysiology of anovulation.
PATHOPHYSIOLOGY To develop an approach to the problem of anovulation, one must first have a clear understanding of the components of normal ovulation. The clinical history and functional inquiry can then be
The pathway ultimately responsible for ovulation is initiated by pulsatile release of gonadotropin-releasing hormone (GnRH) from neurons in the arcuate nucleus of the hypothalamus into the portal circulation. From there, GnRH induces release of the anterior pituitary hormones, luteinizing hormone (LH) and follicle-stimulating hormone (FSH). The amplitude and frequency of GnRH release are critical to normal functioning of the HPO axis.2 Numerous hormones and neurotransmitters are known to modulate GnRH release, including dopamine, norepinephrine, neuropeptide Y, and endorphins. Factors affecting release of these hormones and neurotransmitters or the physical delivery of GnRH to the anterior pituitary may ultimately disrupt ovulation. Suppression of GnRH release is associated with excessive stress (including severe chronic disease) and eating disorders, such as anorexia nervosa and bulimia. Even in the face of a normal body mass index (BMI), excessive exercise or disordered eating such as bulimia nervosa may result in ovulatory dysfunction. A spectrum of GnRH deficiency may be observed, ranging from altered frequency and amplitude of GnRH pulses to complete suppression of GnRH activity. The resulting clinical presentation ranges from oligomenorrhea to amenorrhea. Because GnRH cannot be measured directly, this is a diagnosis of exclusion. Women with hypothalamic causes of amenorrhea rarely report hypoestrogenic symptoms such as vasomotor flushing. In the presence of chronic hypoestrogenism, estrogen receptor down-regulation renders them relatively insensitive to the usual hypothalamic-mediated vasomotor symptoms triggered by low estrogen levels. This same phenomenon also renders them relatively refractory to ovulation induction with clomiphene citrate.
Amenorrhea
Normal cycles Short follicular phase
Short luteal phase
Erratic bleeding
Anovulation
Oligomenorrhea Light bleeding
Figure 19-1
The Hypothalamus
Heavy bleeding
Spectrum of menstrual bleeding patterns, from normal ovulatory cycles to amenorrhea.
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Section 3 Adult Reproductive Endocrinology Excessive cortisol secretion (due to high corticotropinreleasing hormone activity), high levels of endogenous neuropeptide Y and opioids (specifically endorphins) are all thought to play a role in suppression of GnRH activity associated with psychological stress and eating disorders. Less commonly, injury, infection, or central nervous system (CNS) tumors may interfere with delivery of GnRH to the anterior pituitary via the portal circulation. Hypothalamic dysfunction or failure has been reported following severe deceleration injuries that cause pituitary stalk transection, CNS tumors such as craniopharyngiomas or hamartomas that cause stalk compression, and infiltrative diseases such as tuberculosis or sarcoidosis. Lastly, hypogonadotropic hypogonadism may result from a GnRH receptor defect or GnRH deficiency due to failure of migration of the GnRH-producing neurons (Kallmann syndrome). These patients generally present with primary amenorrhea and lack of secondary sexual development rather than with secondary ovulatory disturbances. More recently, the role of leptin in maintenance of BMI, regulation of appetite, and control of reproductive function has been investigated. Leptin is a 146-amino acid protein hormone expressed in numerous sites but mainly in adipose tissue. It has been shown to have a direct stimulatory effect on GnRH pulsatility, as well as LH/FSH secretion from the anterior pituitary, and is likely central to control of the HPO axis through a number of complex endocrine and paracrine actions.3 Leptin may act as a sensor of energy deficiency, limiting the high-energy cost of reproduction and growth during periods of starvation. Concentrations decrease rapidly with fasting, resulting in suppression of reproductive, thyroid, and growth hormones. A preliminary study suggests that administration of recombinant human leptin may reverse the neuroendocrine abnormalities associated with hypothalamic amenorrhea, inducing a return of hormone secretion reminiscent of puberty.4
Pituitary Gonadotropins At the extremes of reproductive age, anovulation can be considered to be physiologic. With the onset of puberty, the hypothalamus is released from its prepubertal negative inhibition, and pulsatile GnRH secretion is initiated. This pulsatile GnRH release is initially nocturnal, and as puberty progresses, pulsatile secretion occurs throughout the day. In response to increasing secretion of GnRH, LH and FSH are released from the anterior pituitary gland in a similar pulsatile fashion, resulting in the production of gonadal steroids that will ultimately result in thelarche and menarche. The secretion of LH and FSH in response to GnRH stimulation varies as puberty progresses. As the HPO axis matures, it is common to see abnormalities in ovulatory function. The average time from onset of menses to establishment of regular ovulatory cycles is 2 to 3 years.5
The Ovary
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Depletion of follicles is a common cause of abnormalities in ovulatory function during the perimenopausal transition. Early follicular (day 3) FSH levels rise due to the relative resistance of the remaining follicles to FSH-dependent stimulation and a concomitant decrease in serum inhibin. Accelerated follicular
development may occur in response to increased FSH levels, with elevated estradiol secretion early in the follicular phase, ovulation as early as day 8 to 11, and corresponding shortening of the menstrual interval (e.g., from a 28-day to a 23-day pattern).6,7 As follicular number and responsiveness decline, the pattern progresses to oligo-ovulation or anovulation and eventual amenorrhea. This inevitable process of reproductive aging usually begins in the late 30s and may become clinically manifest with changing menstrual patterns throughout the 40s.7 A similar process, albeit occurring at an earlier age, may occur in young women who develop premature ovarian failure with loss of ovarian function before age 40.8,9 Some young women with premature ovarian failure experience premature follicular depletion; others likely have a normal complement of follicles that are unresponsive to gonadotropin stimulation, possibly on an autoimmune basis. Young women with premature ovarian failure may also experience sporadic and transient return of ovarian function after diagnosis, ranging from intermittent estrogen-withdrawal bleeding to normal ovulatory cycles and the possibility of conception.10–12 Lastly, the most common cause of ovulatory dysfunction is PCOS, a complex condition of uncertain etiology. PCOS is the most common endocrine disorder in women and is characterized by hyperestrogenic hyperandrogenic chronic anovulation, which may present clinically with various ovulatory and menstrual disorders, infertility, acne, hirsutism, and obesity.13 Numerous metabolic aberrations may also be associated with PCOS, including obesity, insulin resistance, type 2 diabetes, dyslipidemia, and cardiovascular disease. Insulin resistance appears to play a central role in the reproductive dysfunction and long-term health consequences of PCOS.12 When evaluating women with ovulatory dysfunction, it is important to recognize that PCOS is a syndrome with a broad spectrum of clinical phenotypes, and that no existing classification will encompass all possible phenotypes. The Rotterdam PCOS consensus workshop recently published revised criteria for the diagnosis of PCOS.14 After exclusion of other etiologies (congenital adrenal hyperplasia, androgen-secreting tumors, Cushing’s syndrome), two of three of the following criteria must be present to establish a diagnosis of PCOS: ● ● ●
Oligo-ovulation or anovulation Clinical and/or biochemical signs of hyperandrogenism Polycystic ovaries (presence of ≥ 12 follicles in each ovary measuring 2 to 9 mm and/or ovarian volume ≥ 10 mL).
Although frequently associated with PCOS, obesity in itself may contribute to ovulatory dysfunction.15 Numerous studies, including the Nurses’ Health Study, have reported increased rates of ovulatory infertility with increasing BMI.16,17 It is believed that obesity leads to a state of functional hyperandrogenism. Central (abdominal) obesity is associated with insulin resistance and high circulating insulin levels. Because the production of sex hormone-binding globulin (SHBG) in the liver is directly inhibited by insulin, it follows that women with central obesity have lower levels of SHBG and higher levels of free testosterone than age- and weight-matched controls with peripheral obesity.18 This functional hyperandrogenism, in combination with increased peripheral aromatization of estrogen in adipose tissue, leads to alteration in the balance of sex steroids and ultimately contributes to ovulatory dysfunction.
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Chapter 19 Anovulation and Ovulatory Dysfunction Other Endocrine Disorders A number of other endocrine disorders may result in ovulatory dysfunction through disruption of the HPO axis. Hyperprolactinemia, for example, leads to suppression of GnRH secretion.19 Similarly, increased thyrotropin-releasing hormone (TRH) activity in women with hypothyroidism ultimately results in reduced GnRH pulsatility through the direct stimulatory effect of TRH on prolactin secretion. Hyperthyroidism may result in a range of menstrual disturbances, from frequent heavy bleeding to amenorrhea.
the fertile population and are hampered by a lack of consensus regarding diagnostic criteria. Performance of repeated endometrial biopsies to assess histology is often impractical and the interpretation of results limited by a high degree of interobserver variability. Similarly there is no agreement on the appropriate normal values for serum progesterone. Finally, lack of a clear treatment effect with progesterone supplementation has led many to question the importance of luteal phase defect as a cause of infertility.24–26 Luteinized Unruptured Follicle
Women with both classic and late onset congenital adrenal hyperplasia (CAH) may present with ovulatory disturbances similar to PCOS.20 Menstrual abnormalities in these women were initially attributed to inadequate glucocorticoid suppression of adrenal androgen production, resulting in suppression of the HPO axis. Particularly in classic CAH, there is evidence of ovarian hyperandrogenism similar to PCOS despite adequate adrenal suppression with dexamethasone. It has been postulated that perinatal exposure to hyperandrogenism in women with CAH results in hypersecretion of LH in response to GnRH stimulation at puberty. This allows the development of ovarian hyperandrogenism independent of control of adrenal androgen production.21 A similar abnormality has been reported but is less common in late-onset CAH.
Lastly, luteinized unruptured follicle syndrome has been reported as a transient or ongoing cause of ovulatory disturbance. The syndrome involves absence of sonographic signs of ovulation or lack of an ovulatory stigma at laparoscopy 48 to 72 hours after the LH surge. The phenomena may occur in conjunction with periovulatory nonsteroidal anti-inflammatory ingestion, leading to inhibition of prostaglandin-induced follicular rupture.27,28 Other cases have been reported in conjunction with suboptimal doses or improperly timed human chorionic gonadotropin injections during ovulation induction cycles.29 Aside from these iatrogenic cases, there is no clear etiology, no documented treatment, and considerable controversy over the diagnostic criteria with their inherent variability and observer biases.29,30 A survey of practice patterns in the United States indicated that only 8% of university-based board-certified reproductive endocrinologists would screen for this disorder.31
Luteal Phase Defect
ESTABLISHING A DIAGNOSIS
Congenital Adrenal Hyperplasia
Luteal phase defect is a controversial entity thought to consist of inadequate endometrial development in the luteal phase leading to impaired endometrial receptivity, failed implantation, and early pregnancy loss. Qualitative or quantitative progesterone deficiency is felt to be central to the abnormal endometrial development. Two subgroups likely exist: 1. Short luteal phase. A short luteal phase (<10 days) is usually documented by urinary LH testing or basal body temeperature (BBT) charting. This is generally secondary to suppression of pulsatile GnRH secretion,19 leading to inadequate luteinization and reduced progesterone production. Short luteal phases occur in association with other endocrine disorders (e.g., hyperprolactinemia or hypothyroidism) or during development of or recovery from the hypothalamic-pituitary suppression that accompanies lactational amenorrhea, steroidal contraceptive use, and strenuous exercise. Correction of the underlying cause usually results in normalization of the luteal phase. 2. Disordered endometrial development. Endometrial histologic development that lags 2 or more days behind chronologic dating is often independent of luteal phase length.22 This variant of luteal phase defect is thought to be due to suboptimal progesterone secretion or inadequate endometrial response to progesterone. Although the precise etiology is uncertain, it is known to occur more commonly in the exaggerated hormonal milieu that accompanies ovarian stimulation with exogenous gonadotropins, with or without GnRH analog therapy.23 The role of luteal phase defect in infertility remains controversial, however. Studies designed to address this issue have demonstrated a significant prevalence of luteal phase defect in
The diagnosis of anovulation or ovulatory dysfunction can be made solely on the basis of history in most cases. Menstrual bleeding occurring at regular intervals between 21 and 35 days, particularly in the presence of premenstrual molimina (i.e., breast tenderness, abdominal bloating, mood disturbance) is suggestive of ovulation; bleeding at longer or irregular intervals generally reflects anovulation. Identification of more subtle ovulatory dysfunction may require the use of ancillary testing such as urine LH monitoring, BBT charting, or luteal phase serum progesterone measurement. A woman with 40- to 50-day cycles may indeed be ovulatory, albeit with a prolonged and irregular follicular phase. The diagnosis will be most likely be made from biphasic BBT charts in which the progesterone-induced temperature rise occurs late (e.g., from day 26 to 36 in this case). Serum progesterone measurements are helpful if obtained in the 7 to 10 days prior to the next menses, but appropriate timing can be challenging in women with long or erratic cycle intervals. Progesterone levels may be misleading in this case if performed on the “traditional” day 21, although they could confirm ovulation if ordered on day 38 to 39, for example. Basal body temperature charting or urine LH testing may also be useful in identification of women with ovulatory cycles accompanied by a shortened luteal phase (<10 days). This can occur in the context of a normal menstrual interval but is frequently associated with a short menstrual interval (e.g., every 21 to 24 days) and should prompt evaluation of thyroid function and prolactin secretion.
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Section 3 Adult Reproductive Endocrinology Considerable controversy exists over the criteria used to define luteal phase defects.25,32 Histologic dating of a luteal phase endometrial biopsy specimen has been considered the gold standard, requiring a 2- to 3-day difference between histologic and chronologic dating in two separate cycles.22 However, the test is invasive and uncomfortable, and suffers from substantial intraobserver and interobserver variability.33 Serum progesterone measurements are less invasive, although less accepted due to debate over the threshold level used for diagnosis, the number of suboptimal tests needed, and the relatively poor correlation with endometrial response.24,25,34 Progesterone secretion is both pulsatile (in response to episodic LH release) and parabolic (with peak levels in the midluteal phase), so low levels may occur physiologically in the trough prior to each LH pulse and at the beginning and end of each luteal phase.35 The threshold progesterone value used to differentiate ovulatory from anovulatory cycles (6 to 18 nmol/L or 2 to 5 ng/mL) should not be confused with that suggested for the diagnosis of defective luteal phase (21 to 32 nmol/L or 7 to 10 ng/mL).24,34
DIAGNOSIS Various classification systems have been developed for ovulatory disorders (Table 19-1). Such systems also provide the basis for a timely and cost-effective evaluation. They revolve around three key principles that can also be used to guide the history, physical examination, investigations, and management (Table 19-2).
History History taking in women with ovulatory disorders focuses on evaluating the current and previous menstrual pattern, identifying precipitating factors or underlying medical disorders that require specific therapy, and assessing associated symptoms that may also require treatment. The menstrual history should commence with menarche and a brief assessment of the pubertal development, particularly in the adolescent patient. This may be addressed simply by ensuring that pubertal development occurred in parallel with
Table 19-2 Key Principles for Evaluation of Ovulatory Dysfunction 1. Identify hypoestrogenic patients who lack spontaneous or progestin-induced menstrual bleeding. 2. Differentiate hypogonadotropism, hypergonadotropism, and normo-gonadotropism. 3. Exclude underlying medical conditions that produce secondary ovulatory dysfunction.
the patient’s peers. Bear in mind that anovulatory cycles can be a normal physiologic pattern up to 3 years from menarche. The menstrual pattern can be described as the number of menses experienced per year (e.g., 2 or 3 menses per year) or as the shortest and longest interval between menstrual bleeding (e.g., 35 to 90 days). Cycles occurring at intervals longer than 35 days are considered oligo-ovulatory or anovulatory and may often be prolonged or heavy. In some cases, helpful information about follicular or luteal phase length and the timing of ovulation may be gleaned from BBT charts or urinary ovulation detection kits. Although no menstrual pattern is pathognomonic of the underlying condition, shortened follicular phases (e.g., 8 to 10 days) often occur early in the perimenopausal transition, shortened luteal phases (e.g., <10 days) are common with hyperprolactinemia, whereas infrequent, heavy menses are more common with PCOS. A review of the hypothalamic-pituitary axis may reveal precipitating factors or underlying medical disorders that require specific investigation and treatment. However, many of these symptoms are nonspecific. Hypothalamic factors are common among thin women who present with oligomenorrhea or amenorrhea. Questioning should include sources of excessive life stress, chronic illness, excessive exercise, significant weight change, disordered eating, and an overall preoccupation with thinness.13 Recall that women with hypothalamic causes of amenorrhea rarely report hypoestrogenic symptoms such as vasomotor flushing. Symptoms of pituitary adenoma or prolactin excess such as severe headaches, visual field change (typically bitemporal
Table 19-1 Classification of Ovulatory Disorders
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HPO* Axis
Clinical Presentation
Hormonal Features
Examples
Hypothalamic-pituitary failure
Absence of spontaneous or progestinwithdrawal bleeding
Hypogonadotropism Low or normal FSH Low estradiol
Kallmann syndrome Anorexia nervosa
Hypothalamic-pituitary dysfunction
Presence of spontaneous or progestinwithdrawal bleeding
Normogonadotropism Normal FSH Normal estradiol ± Hyperandrogenism
PCOS Stress- or weight-related anovulation Idiopathic ovulatory dysfunction
Ovarian failure
Progressive loss of spontaneous and progestinwithdrawal bleeding Vasomotor symptoms
Hypergonadotropism High FSH Low estradiol
Premature ovarian failure Perimenopause
Secondary HPO dysfunction
Variable
Variable Low/normal FSH Low/normal estradiol
Hyperprolactinemia Thyroid disease Congenital adrenal hyperplasia Tumors
*Hypothalamic-pituitary-ovarian axis
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Chapter 19 Anovulation and Ovulatory Dysfunction hemianopsia), or galactorrhea should be elicited. A medication history may reveal drugs that affect prolactin secretion, including dopamine antagonists (metoclopramide, domperidone) and antipsychotics (risperidone, haloperidol, phenothiazines). Symptoms of thyroid dysfunction (particularly hypothyroidism) are common and notoriously nonspecific, but should be sought in addition to a personal or family history of thyroid disease. The most common disorder of the HPO axis that will be encountered in anovulatory patients is PCOS. Menstrual disorders, infertility, weight gain, central obesity, hirsutism, and acne are common presenting symptoms. Some affected women will also present with a history of known hypertension, dyslipidemia, or glucose intolerance. Other causes of hyperandrogenism must be excluded, including androgen-secreting tumors, CAH, and Cushing’s syndrome.14 In the assessment of hirsutism, it is important to differentiate between the slow insidious onset of hirsutism associated with PCOS or late-onset CAH and the rapidly progressive onset of hirsutism associated with virilization due to an androgensecreting tumor. Symptoms of true virilization, such as deepening of the voice, clitorimegaly, and change in body habitus (not simply weight gain) must be excluded because their presence mandates much more extensive investigation to rule out the presence of an androgen-secreting tumor. Specific questions regarding the severity of hirsutism will aid in assessing the need for and response to treatment. It is often helpful to document the frequency, duration, and method of hair removal and to assess a change in those parameters with treatment (i.e., electrolysis diminishing from 30 to 15 minutes weekly). The possibility of premature ovarian failure is high in a young woman who presents with amenorrhea and vasomotor symptoms. However, these patients will frequently progress through a period of shortened menstrual cycles or oligo-ovulation before the onset of amenorrhea.7 Depending on the degree and duration of hypoestrogenism, progestin-withdrawal bleeding may disappear. Symptoms of hypoestrogenism may be absent if the onset was insidious; other women will present with the sudden onset of hot flashes, sleep disturbances, and mood disturbances that may be more marked than those typically seen in the natural menopausal transition. A history of precipitating factors such as chemotherapy, radiation, or extensive ovarian surgery should be sought. A family history of premature ovarian failure is present in 4% to 30%.10 A personal or family history of autoimmune disease such as diabetes, thyroid disease, Addison’s disease, lupus, or vitiligo can also be a valuable clue to potential autoimmune-mediated causes of premature ovarian failure.10 In any patient presenting with ovulatory dysfunction, the desire for fertility, the need for contraception, and the need for menstrual regulation and endometrial protection will necessarily guide the therapeutic options considered. The age of the patient and the duration of anovulatory cycles are important in establishing the potential risk of endometrial hyperplasia and the need for an endometrial biopsy and subsequent endometrial protection.
elevated BMI (>30 kg/m2) may be suggestive of hypothyroidism (if related to recent increase in weight) or insulin resistance associated with PCOS. Other features of insulin resistance associated with PCOS include central obesity (increased waist/hip ratio) or the presence of acanthosis nigricans, a grey-brown velvety pigmentation frequently seen in the neck, axillae, and groin. Finally, consideration of PCOS should prompt an assessment of clinical hyperandrogenism. The presence of acne or hirsutism and the pattern and severity of each should be documented. An objective tool for assessment of hirsutism is the Ferriman-Gallwey score,36 which is helpful, particularly in the context of research studies in which objective response to antiandrogen treatment is desirable; its utility in routine clinical assessment may be more limited. Male pattern alopecia (temporal hair loss) is also a feature of clinical hyperandrogenism. The remainder of the physical examination should include a systematic head to toe assessment, including visual fields (bitemporal hemianopsia), a thyroid examination to exclude goiter, and breast examination for galactorrhea. The abdominal examination should pay particular attention to the presence of striae and/or male pattern hair distribution. Extensive abdominal striae may suggest cortisol excess associated with Cushing’s syndrome; a male escutcheon is further evidence of clinical hyperandrogenism. Abdominal or pelvic masses are encountered rarely.
Physical Examination
Gonadotropins
The physical examination of the anovulatory patient should commence with basic observations including height, weight, calculation of BMI, and assessment of body habitus. Low BMI (<20 kg/m2) may be a clue to hypothalamic dysfunction, whereas
The gynecologic examination should commence with assessment of the external genitalia for clitorimegaly. Normal estrogenization is confirmed by healthy vaginal rugae, often accompanied by copious clear cervical mucus. In contrast, low estrogen levels due to prolonged hypothalamic anovulation or premature ovarian failure results in pale, smooth vaginal mucosa with little cervical mucus. Bimanual examination should be performed to rule out adnexal masses. Finally, in women with prolonged anovulation and evidence of normal estrogenization, an endometrial biopsy should be considered to exclude pathology such as endometrial hyperplasia.
Laboratory Evaluation The systematic and cost-effective laboratory evaluation of ovulatory dysfunction is based on the three key principles described in Table 19-2. In the initial investigation, one should always consider the possibility of pregnancy and perform a pregnancy test when clinically indicated. Once pregnancy has been excluded, the investigation should commence with measurement of thyrotropin, prolactin, and FSH (Fig. 19-2). Thyrotropin and Prolactin
Elevated thyrotropin or prolactin levels will require appropriate investigation and therapy (see Chapter 22), keeping in mind that elevation of both thyrotropin and prolactin is usually the result of hypothyroidism and that hyperprolactinemia will respond to treatment of the underlying thyroid condition.
For the purpose of assessing ovarian reserve, measurement of early follicular FSH (day 3) is ideal; however, this may not be practical in the setting of very infrequent menses.6 Elevated FSH concentrations raise the possibility of premature ovarian failure and should be repeated in another
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Low or normal FSH
High FSH (>15-20 IU/L)
Assess estrogenization: progestin challenge test if amenorrheic or uncertain hypoestrogenism
Confirm high FSH at least one month later, on day 3 if possible
Abnormal TSH or prolactin
Treat underlying problem
(Impending) Premature Ovarian Failure Progestin withdrawal bleed (–)
Spontaneous menses or (+) Progestin withdrawal
Hypothalamic Amenorrhea
If <40 yrs, look for chromosomal and autoimmune disorders
Ovulatory Dysfunction
Clinical or biochemical hyperandrogenism
Virulization present: Rule out Tumor
Virulization absent: PCOS
No clinical or biochemical hyperandrogenism
Unexplained Ovulatory Dysfunction
Assess lipid profile, glucose tolerance and insulin resistance Figure 19-2
282
Guidelines for the investigation of ovulatory dysfunction.
cycle for confirmation. Although there is considerable variation among centers, FSH concentrations above 10 to 15 IU/L are suggestive of diminished ovarian reserve, whereas concentrations above 15 to 20 IU/L are highly suggestive of impending or established premature ovarian failure.6 If confirmed, additional testing is prudent in women under age 40 to identify underlying karyotype abnormalities (e.g., Turner’s mosaicism), fragile X premutations, and associated autoimmune disorders.9 Low or normal FSH requires further assessment of estrogen status. If the patient clearly has normal estrogen levels based on physical examination (vaginal rugae, watery cervical mucus), further investigation may not be required. If this is unclear clinically, a progestin challenge test should be done. Absence of bleeding following administration of a progestin challenge suggests clinical hypoestrogenism and is in keeping with a diagnosis of hypothalamic dysfunction. A positive progestin challenge is in keeping with ovulatory dysfunction such as PCOS.
Androgens
In the absence of clinical hyperandrogenism, identification of biochemical androgen excess is rarely of value in the management of ovulatory dysfunction, because the course of management (ovulation induction or endometrial protection) would not be altered by its presence. Therefore, screening for biochemical evidence of hyperandrogenism in every patient with anovulation is generally unnecessary and not cost-effective. In the context of clinical hyperandrogenism, it is essential to rule out the possibility of an androgen-secreting tumor. This can frequently be done on the basis of history and physical examination alone. In the absence of rapid onset of hirsutism associated with virilization, an androgen-secreting tumor is extremely unlikely, and serum androgen screening is not required. If uncertain, measurement of testosterone (adrenal or ovarian origin), androstenedione (ovarian origin), and dehydroepiandrostenedione sulfate (adrenal origin) may be helpful.
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Chapter 19 Anovulation and Ovulatory Dysfunction The reliability of different methods of testosterone assessment is highly variable between laboratories. Depending on local assay methodology, free testosterone or free androgen index will likely represent the most accurate assessment of biologically active testosterone. Once androgen-secreting tumors have been ruled out, the most likely diagnosis is PCOS. However, late-onset (nonclassic) CAH may be clinically indistinguishable from PCOS. For patients desiring pregnancy, CAH should be excluded by assessment of a follicular phase 17-hydroxyprogesterone level and possibly a corticotropin stimulation test. The value of screening for this rare disorder in every anovulatory patient with evidence of hyperandrogenism is controversial; in the absence of virilizing symptoms or the desire for pregnancy, management is essentially the same as for PCOS. Finally, a diagnosis of PCOS should prompt an assessment of associated conditions, including hypercholesterolemia and insulin resistance. Although the benefit of screening for these conditions in thin women with PCOS is unclear, a fasting cholesterol panel and an assessment of insulin resistance/glucose intolerance (glucose tolerance test ± insulin levels) are certainly warranted in obese women with PCOS or those with other risk factors (e.g., family history of hypercholesterolemia or type 2 diabetes). The etiology of ovulatory dysfunction will ultimately remain unclear (idiopathic ovulatory dysfunction) for many patients who do not strictly fit the criteria for a diagnosis of PCOS. Once diseases requiring specific therapy have been excluded, it is acceptable to manage these patients according to their presenting symptoms and desire for pregnancy.
Progestin Challenge Test If the estrogen status of the patient is unclear from the physical examination, a progestin challenge test can be arranged at the same time as the initial blood work. Medroxyprogesterone acetate (5 to 10 mg) is administered daily for 7 to 14 days, after which a menstrual bleed should ensue in normally estrogenized patients. Any amount of spotting or bleeding in the 2 weeks after progestin withdrawal is considered a positive progestin challenge.
MANAGEMENT Management options for women with ovulatory disorders vary according to the presenting symptoms and clinical circumstances. The principles of therapy involve the following: 1. Identify underlying disorders that require specific treatment 2. Determine if the woman desires pregnancy, contraception, or menstrual regulation 3. Offer individualized therapy based on the presenting signs and symptoms. After ruling out underlying medical disorders that require specific therapy, the next priority is to identify predisposing or contributing factors and provide appropriate counseling or therapy. Examples include excessive stress, anxiety or depressive disorders, excessive weight gain, overt or insidious eating disorders, strenuous exercise without appropriate nutritional intake, or a preoccupation with thinness. Remember that the menstrual cycle is often a barometer of underlying health. The etiology of hypothalamic amenorrhea can often be thought of as
“energy drain,” whether it be emotional, physical, or caloric. There is a metabolic cost associated with a menstrual cycle, a luteal phase thermal shift, and subsequent menstrual blood loss. Ovulatory dysfunction is unlikely to resolve until the HPO axis senses sufficient “energy” in reserve to cover this metabolic expenditure and sustain an ensuing pregnancy. The process of identifying and discussing factors that contribute to HPO dysfunction is key to initiating the necessary lifestyle changes and/or therapy.13,37 The next step is to assess the woman’s needs in terms of contraception, menstrual regulation, and the management of any associated symptoms.
Fertility For women who desire fertility, induction of ovulation can produce the secondary benefits of cycle control and endometrial protection. Depending on clinical circumstances, it may be prudent to rule out endometrial hyperplasia prior to ovulation induction attempts. For overweight or underweight women, achievement of a healthy body weight and healthy eating habits may be sufficient to correct the underlying ovulatory disorder. Increased activity and modest weight reduction (at least 5% of body weight) among obese oligo-ovulatory women (BMI >30 kg/m2) with PCOS leads to improvement in ovulatory function and an increase in spontaneous and treatment-associated pregnancy rates.38,39 Similarly, ovulatory function frequently improves among women with a low BMI in response to stepwise reductions in exercise frequency or intensity, increased BMI, increased caloric and protein intake, and/or modification of restricted eating patterns.13 After normalization of body weight and other lifestyle changes as appropriate, ovulation can be induced with clomiphene citrate.40 Induction of ovulation with clomiphene citrate is effective in 75% to 80% of patients, although only 40% to 50% will conceive.41 Predictors of clomiphene citrate resistance include high basal FSH concentrations (impending ovarian failure), absence of progestin-induced withdrawal bleeding (hypogonadotropic amenorrhea), and PCOS associated with high BMI (>30 kg/m2) or severe hyperandrogenism.42,43 More recently, aromatase inhibitors such as letrozole have been used for ovulation induction.44,45 Their role in the treatment of PCOS, and specifically clomiphene-resistant PCOS, remains unclear.46 Various approaches have been examined for the treatment of clomiphene-resistant anovulation. Extending the duration of clomiphene citrate administration to 7 to 10 days (i.e., 100 mg from days 3 to 12) is useful in some women, with a total dose that does not exceed the amount used in a conventional protocol of 200 mg for 5 days.42 In clomiphene-resistant women with documented insulin resistance and/or impaired glucose tolerance, addition of metformin may improve the response to clomiphene citrate.47 Appreciating that insulin resistance is felt to be central to the pathophysiology of PCOS, particularly in obese women, there has been great interest in the use of insulin-sensitizing agents as an adjunct to ovulation induction therapy. A number of randomized, controlled trials support improved ovulation rates with metformin, either alone or in conjunction with clomiphene citrate.47,48 A variable improvement in cycle parameters and
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Section 3 Adult Reproductive Endocrinology pregnancy rates has been reported with metformin use during in vitro fertilization treatment cycles.47 Limited information exists regarding the outcome of pregnancies conceived on metformin or those pregnancies in which metformin was continued during pregnancy. Similarly, there is little information about the optimal duration of therapy prior to conception. It has been our practice to discontinue metformin when conception occurs, or after a 3-month trial if there has been no appreciable weight loss or improvement in clinical or endocrine parameters. Women who do not ovulate or conceive after making appropriate lifestyle changes and receiving therapy with oral agents become candidates for injectable exogenous gonadotropins. Women with hypothalamic amenorrhea or WHO group I ovulatory disorders lack endogenous gonadotropin activity. As such, exogenous gonadotropins can be expected to restore normal ovulation and pregnancy rates.49 A less predictable response is observed in the heterogeneous group of women with WHO group II ovulatory disorders. Predictors of lower ovulation and pregnancy rates include increasing age, obesity, hyperandrogenism, and failure to conceive despite successful ovulation with clomiphene citrate.49,50 Due to the cost associated with exogenous gonadotropin therapy and the increased risk of multiple pregnancy, some women with clomiphene citrate-resistant PCOS will elect to undergo laparoscopic ovarian drilling in an attempt to restore spontaneous ovulatory function. This technique has been shown to reduce circulating androgen levels and restore ovulation in up to 75% of women treated.51 Concern regarding the longevity of its effect and ultimately compromised fertility due to postoperative adhesions has limited the broad application of this technique. However, it is a reasonable alternative in selected patients.
Contraception
284
If contraception is needed, combination oral contraceptives (OCs) are generally the first line of therapy because of their combined contraceptive and noncontraceptive benefits. In addition to contraception, they provide menstrual regulation, protection of the endometrium from the effects of prolonged unopposed estrogen stimulation, and relief of acne and hirsutism in hyperandrogenic women. The antiandrogenic effects arise predominantly from hypothalamic-pituitary suppression that leads to diminished androgen production from the ovarian stroma. In addition, the estrogen component rapidly produces an increase in hepatic SHBG production, resulting in a decrease in free testosterone levels.52 Where available, cyproterone acetate, the progestational component of some OCs, has intrinsic antiandrogenic activity and is an effective choice for the treatment of menstrual irregularities associated with hyperandrogenism. Progestin-only contraceptives (tablets, depot injections, and implants) provide contraception, cycle control, and endometrial protection and may be appropriate alternatives for some women unable to tolerate estrogen-containing OCs or in whom such OCs are contraindicated. Relief of androgenic conditions such as acne and hirsutism is more variable. Progestin-only therapy produces suppression of the HPO axis with a resulting reduction in ovarian androgen production, although possibly to a lesser degree than combination OCs. Although testosterone clearance from the circulation is increased, there is no effect on SHBG production.53 In addition, the synthetic progestins possess some
intrinsic androgenic activity that, for some women, will result in a paradoxical exacerbation of their androgenic symptoms.52
Cycle Control and Endometrial Protection If contraception is not required and fertility is not an issue, the need for menstrual cycle control and endometrial protection should be assessed. There are no clear guidelines for the frequency or pattern of menstrual bleeding that ensures endometrial protection in this young population of women. However, chronic anovulation is associated with an increased risk of endometrial hyperplasia and neoplasia,54,55 particularly in obese women (weight >90 kg).56 Clinical experience suggests that progestinwithdrawal bleeds should be induced every 4 to 12 weeks in the face of chronic anovulation or if menses occur less frequently than every 8 weeks.57 Endometrial biopsy should be performed prior to therapy in women with prolonged anovulation, in those with irregular or heavy bleeding, and in women with other risk factors for endometrial hyperplasia (weight >90 kg, infertility with nulliparity, or PCOS).51,56,58–60 For women who do not wish to have cyclic menses, hypomenorrhea or amenorrhea can be induced with continuous systemic progestin therapy using a depot progestin preparation, progestin implants, or continuous local administration via a progesterone-containing intrauterine system.
Hirsutism Women with hyperandrogenic anovulation (PCOS) frequently experience acne or hirsutism. In women desiring pregnancy, mechanical hair removal is the only appropriate option given the concern regarding antiandrogen therapy in pregnancy. However, for those who are not attempting conception, various combination therapies are available, some of which provide simultaneous contraception and cycle control. The most effective treatment for hirsutism usually involves a combination of weight loss (where appropriate), mechanical hair removal, and medical therapy. The latter usually involves androgen suppression (e.g., oral contraceptives) and/or specific antiandrogen therapy (e.g., with spironolactone, cyproterone acetate, flutamide, or finasteride).
Ovarian Failure Fertility is often still a concern for young women with hypergonadotropism (see Chapter 20). However, women with rising FSH levels, diminished ovarian reserve, or premature ovarian failure are rarely suitable candidates for ovulation induction therapy.60 Depending on age and other factors, there is a small chance of spontaneous conception during occasional ovulatory cycles. Approximately 5% to 10% of young women with premature ovarian failure conceive spontaneously if they enter into a remission after the diagnosis. Beyond this, oocyte donation offers the only realistic possibility of achieving a pregnancy.10,11 Women with rising FSH levels have a presumptive diagnosis of impending ovarian failure, but may still have a relatively normal menstrual pattern and few other symptoms. Although they generally require no specific therapy, they may benefit from counseling about cardiovascular and bone health, including a healthy diet, regular weight-bearing and muscle strengthening
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Chapter 19 Anovulation and Ovulatory Dysfunction exercise, smoking cessation, modest alcohol intake, and appropriate intake of calcium and vitamin D. As ovarian function declines and eventually ceases, women with premature ovarian failure may benefit from measures aimed at menstrual cycle control, endometrial protection, relief of hypoestrogenic symptoms, and osteoporosis prevention. Either cyclic OCs or traditional estrogen/progestin hormone replacement therapy can be used for this purpose, although OCs may achieve better cycle control in cases where some residual ovarian function persists. Young women who are still hoping for the possibility of a remission and a pregnancy may be better served by low-dose hormone replacement therapy using micronized estradiol and progesterone. Such low-dose regimens are not likely to inhibit or mask the return of spontaneous ovulation during a remission, nor do they pose safety concerns about inadvertent exposure during an early pregnancy because they involve hormones identical to those produced by the human ovary.
Long-term Health Issues Traditionally, the focus of gynecologic treatment in women with PCOS has been on infertility, hirsutism, and menstrual irregularity. However, women with hyperandrogenism and PCOS are also at risk for long-term health sequelae, including
android obesity, diabetes, dyslipidemia, hypertension, and heart disease. Many women with PCOS present early in their reproductive years, giving gynecologists a unique opportunity to modify long-term health consequences by encouraging interventions aimed at controlling weight and insulin resistance. Counseling can be offered about lifestyle modifications, including regular exercise, healthy body weight, healthy eating habits, and smoking cessation.
PEARLS ●
●
●
●
●
Ovulatory dysfunction is a spectrum of disorders ranging from amenorrhea to frequent, irregular, and/or heavy menses. Rule out underlying disorders that require specific treatment or have other health implications. The menstrual cycle may serve as a barometer of general health. PCOS is the most common form of ovulatory dysfunction, but many women have a normal workup with no clear etiology for anovulation. Offer individualized therapy based on the presenting symptoms, the desire for pregnancy or the need for contraception, and the associated symptoms (e.g., hirsutism). Arrange follow-up and monitor long-term health consequences.
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46. Al-Omari WR, Sulaiman WR, Al-Hadithi N: Comparison of two aromatase inhibitors in women with clomiphene-resistant polycystic ovary syndrome. Int J Gynaecol Obstet 85:289–291, 2004. 47. Costello MF, Eden JA: A systematic review of the reproductive system effects of metformin in patients with polycystic ovary syndrome. Fertil Steril 79:1–13, 2003. 48. Lord JM, Flight IH, Norman RJ: Insulin-sensitising drugs (metformin, troglitazone, rosiglitazone, pioglitazone, D-chiro-inositol) for polycystic ovary syndrome. Cochrane Database Syst Rev 2003:CD003053. 49. Fluker MR, Urman B, Mackinnon M, et al: Exogenous gonadotropin therapy in World Health Organization groups I and II ovulatory disorders. Obstet Gynecol 83:189–196, 1994. 50. Mulders AG, Laven JS, Eijkemans MJ, et al: Patient predictors for outcome of gonadotrophin ovulation induction in women with normogonadotrophic anovulatory infertility: A meta-analysis. Hum Reprod Update 9:429–449, 2003. 51. Farquhar CM, Lethaby A, Sowter M, et al: An evaluation of risk factors for endometrial hyperplasia in premenopausal women with abnormal menstrual bleeding. Am J Obstet Gynecol 181:525–529, 1999. 52. van der Vange N, Blankenstein MA, Kloosterboer HJ, et al: Effects of seven low-dose combined oral contraceptives on sex hormone binding globulin, corticosteroid binding globulin, total and free testosterone. Contraception 41:345–352, 1990. 53. Gordon GG, Southren AL, Tochimoto S, et al: Effect of medroxyprogesterone acetate (Provera) on the metabolism and biological activity of testosterone. J Clin Endocrinol Metab 30:449–456, 1970. 54. Coulam CB, Annegers JF, Kranz JS: Chronic anovulation syndrome and associated neoplasia. Obstet Gynecol 61:403–407, 1983. 55. Cheung AP: Ultrasound and menstrual history in predicting endometrial hyperplasia in polycystic ovary syndrome. Obstet Gynecol 98:325–331, 2001. 56. Ballard-Barbash R, Swanson CA: Body weight: Estimation of risk for breast and endometrial cancers. Am J Clin Nutr 63:437S–441S, 1996. 57. Balen A: Polycystic ovary syndrome and cancer. Hum Reprod Update 7:522–525, 2001. 58. Gibson M: Reproductive health and polycystic ovary syndrome. Am J Med 98:67S–75S, 1995. 59. Munro MG: Abnormal uterine bleeding in the reproductive years. Part I—pathogenesis and clinical investigation. J Am Assoc Gynecol Laparosc 6:393–416, 1999. 60. Scott RT, Opsahl MS, Leonardi MR, et al: Life table analysis of pregnancy rates in a general infertility population relative to ovarian reserve and patient age. Hum Reprod 10:1706–1710, 1995.
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Section 3 Adult Reproductive Endocrinology Chapter
20
Premature Ovarian Failure Khalid Ataya
INTRODUCTION Premature ovarian failure is defined as hypergonadotropic hypogonadism before age 40. Premature ovarian failure is commonly but not uniformly associated with depletion of ovarian follicles, as is seen in menopause. It results in cessation of regular menses. This condition affects approximately 1% of all women, with 90% of cases occurring between ages 30 and 40. Premature ovarian failure will be found in 10% to 28% of women presenting with primary amenorrhea and 4% to 18% of women presenting with secondary amenorrhea.1 In some cases, the etiology is identical to menopause and thus represents the occurrence of a normal physiologic process at an unusually young age. However, in many cases, the underlying cause is an identifiable pathology. The goal of the clinician is to diagnose and, if possible, treat any ongoing pathologic conditions. Equally important is to help the affected woman reach any unfulfilled reproductive goals via assisted reproductive technologies and psychologically adjust to her condition. Finally, the clinician must ensure that the patient does not suffer the adverse sequelae of prolonged estrogen deprivation, most notably genital atrophy and osteoporosis. This chapter describes normal ovarian development and gradual loss of function. Premature ovarian failure is described, including the various known causes and its standard evaluation. Finally, long-term management is covered.
OVARIAN EMBRYOLOGY The primordial germ cells are known to originate from the endoderm of the yolk sac. These cells can be identified histologically as early as the end of the third week of gestation and migrate to the genital ridge.2 By 8 weeks of intrauterine life, persistent mitosis increases the total number of oogonia to 600,000.3 From this point on, the oogonial endowment is subject to three simultaneous ongoing processes: mitosis, meiosis, and oogonial atresia. At approximately 20 weeks’ gestation, the ovaries possess the maximal complement of up to 6 million to 8 million primary oocytes, approximately two thirds of which have entered and arrested in the prophase of the first meiotic division.1 From midgestation onward, relentless and irreversible attrition progressively diminishes the germ cell endowment of the gonad.4 Some of the oogonia depart from the mitotic cycle to enter the prophase of the first meiotic division between weeks 8 and 13 of fetal life. This change marks the conversion of these cells to primary oocytes well before actual follicle formation.
A role for steroids has been suggested in the control of ovarian primordial follicle assembly and early follicular development.5 It is generally presumed that usually no oogonia are present at birth. Unconfirmed data from mice has challenged this concept, however.6 These investigators have challenged the dogma that germline stem cells are not present and follicular renewal does not occur in the postnatal mammalian ovary. Only 1 million germ cells are present at birth.7 This decreases further to approximately 300,000 by the onset of puberty. Of these follicles, only 400 to 500 (i.e., less than 1% of the total) ovulate in the course of a reproductive lifespan.8 Once formed, the primary oocyte persists in prophase of the first meiotic division until the time of ovulation, when meiosis is resumed and the first polar body is formed and extruded. It is generally presumed that a granulosa cell-derived putative meiosis inhibitor is in play. This hypothesis is based on the observation that denuded (granulosa-free) oocytes are capable of spontaneously completing meiotic maturation in vitro. The primary oocyte is converted into a secondary oocyte by completion of the first meiotic metaphase and formation of the first polar body, before actual ovulation but after the luteinizing hormone (LH) surge. At ovulation, the secondary oocyte and the surrounding granulosa cells (cumulus oophorus) are extruded.
NORMAL OVARIAN AGING Ovarian aging, ultimately leading to ovarian failure and menopause, is a continuum. An early sign is a poor response to ovarian stimulation, followed by menstrual irregularities and eventually ending in cessation of ovarian follicle function. The time interval between the loss of menstrual regularity and the menopause is approximately 6 years, regardless of age at menopause.9 Consistent with this is the finding that the age of last delivery for Canadian women in the nineteenth century showed the same variation as the age of menopause but occurred 10 years earlier.10
Loss of Fertility and Ovarian Aging Natural fertility is known to decline with maternal age. Normal women experience their peak fertility in their early 20s, and an accelerated decline is observed after age 35, as recorded in natural populations around the world.11 The risk of clinical miscarriage and fetal aneuploidy both increase with maternal age, with a steep rise in the late 30s.12,13 The cause of age-related deterioration of oocyte quality is generally accepted to be
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Section 3 Adult Reproductive Endocrinology meiotic nondisjunction due to accumulation of damage in DNA and the microtubules of the meiotic spindle.10 Elevation of early follicular phase follicle-stimulating hormone (FSH) is a hallmark of diminishing ovarian follicular reserve, heralding the menopause transition.14 Elevated FSH levels noted in the premenopause are believed to cause a more rapid recruitment of the cohort of preantral follicles.15 Thus, a period of accelerated oocyte depletion begins until nearcomplete exhaustion of the follicles.16 Poor response to ovarian stimulation most likely represents women in a stage between onset of accelerated decline and total loss of fertility, whereas nonresponse corresponds to a total loss of fertility.17 The basis of the link between a poor response and an early menopause lies in the physiology of follicular development and depletion in the ovary. It has been suggested that the size of the antral follicle cohort is a reflection of the actual resting follicle pool.18–21 “Poor responders” also become menopausal earlier.22,23
Table 20-1 Causes of Premature Ovarian Failure Genetic X chromosome-related Abnormal chromosome number Gene deletions Fragile-X permutations Single-gene mutations Galactosemia Gonadotropin receptor defects Inhibin defects Steroidogenesis enzyme defects Other Genetic syndromes Polyglandular autoimmune syndromes BPEI (blepharophimosis, ptosis, and epicanthus inversis) syndrome Myotonia dystrophica Perrault’s syndrome (congenital deafness) Ataxia-telangiectasia Autoimmune Isolated ovarian disorder Polyglandular autoimmune syndromes 1 and 2 Infectious
Menopause The clinical sequelae of physiologic ovarian failure is menopause, which is defined as the permanent cessation of menses. The median age of menopause in the United States is 51 years, with menopause occurring before age 40 for 1% of women and beyond age 60 for another 1%.24 Despite a progressive prolongation in the mean age of the population and a trend toward accelerated menarche, the age of menopause has remained relatively unaffected over the last century.25 Evidence suggests that the time of the natural menopause is under strong genetic control, although environmental factors can play a significant role.26
PATHOPHYSIOLOGY OF PREMATURE OVARIAN FAILURE
Iatrogenic Chemotherapy Radiation Repetitive ovarian surgery Environmental toxins Idiopathic
Gonadotropin Receptor Polymorphism
A mutation of the FSH receptor has been described in a subset of patients with premature ovarian failure.31 This is associated with loss in receptor function and appears confined to specific families in the Finnish population. A defect in the LH receptor gene associated with ovarian resistance has also been described.32 Inhibin Polymorphism
Premature ovarian failure is the absence of ovarian function before age 40. Although it can be the result of a physiologic process at an unusually young age, it is often due to a broad range of underlying etiologies. Regardless of etiology, the clinical results are decreased fertility, and hypoestrogenemia ultimately manifesting as amenorrhea. In most cases, the etiology of premature ovarian failure will not be clear, and the majority of cases occur sporadically. However, there is a genetic component in some woman, and the risk of premature ovarian failure in a woman with a first-degree relative with premature ovarian failure is between 4% and 30%.27,28 Multiple known etiologies of premature ovarian failure are presented here (Table 20-1).
Genetic Causes Genetic errors such as single-gene defects, abnormalities in the sex chromosomes, and other poorly defined genetic diseases have been associated with premature ovarian failure. The list of potential disorders associated with premature ovarian failure is extensive; however, some general patterns have been observed. Single-Gene Defects
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Single-gene defects may give rise to ovarian failure. These include mutations of FSH and LH receptors, inhibin, and galactosemia, among others.29,30
Mutations in the inhibin α and β genes have been associated with relatively severe symptoms of premature ovarian failure. Amenorrhea usually develops by the second decade of life in 7% of patients exhibiting this mutation, compared to 0.7% of controls.33 Galactosemia
In females affected with this autosomal recessive disorder, the incidence of premature ovarian failure is at least 80%.34 A relevant murine model suggests that this might be due to a decrease in the germ cell number during fetal oogenesis.35 Mutations of the galactose-1-phosphate uridyltransferase gene can also result in premature ovarian failure because of ovarian accumulation of galactose metabolites at toxic levels.36 Other possible mechanisms contributing to premature ovarian failure in these patients include defective isoforms of FSH, and follicular dysfunction that may be related to interference with nucleotide sugar metabolism and the synthesis of galactose-containing glycoproteins and glycolipids consequent to the enzymatic defect.1,37 Other Genetic Abnormalities
Several autosomal loci have been implicated in premature ovarian failure.38 For the chromosome 3 locus, a forkhead transcription factor gene (FOXL2) has been identified, whereby lesions result in decreased follicles. Deficiencies of 17α-hydroxylase and 17,20-desmolase are associated with primary amenorrhea, sexual
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Chapter 20 Premature Ovarian Failure infantilism, and hypertension.1 The impaired steroidogenesis results in loss of negative feedback and elevation in the endogenous FSH. This in turn has been implicated in recruiting larger cohorts of follicles, resulting in an accelerated exhaustion of the oocyte complement.14–16 HLA-DR3-linked predisposition to premature ovarian failure with autoimmune polyglandular endocrinopathies has been demonstrated.39 Autoimmune polyglandular syndromes are a series of disorders characterized by autoimmunity against two or more endocrine organs. BPEI syndrome (blepharophimosis, ptosis, and epicanthus inversis), an autosomal dominant disorder mapped to chromosome 3q, is associated with development of premature ovarian failure.40,41 Myotonia dystrophica, secondary to a mutation of a gene located on chromosome 19, may be associated with premature ovarian failure.41 Moreover, the genes FRAXA and POF1B have been implicated in premature ovarian failure.42 Autosomal disorders such as mutations of the phosphomannomutase 2 (PMM2) gene have been identified in patients with premature ovarian failure.43 Perrault’s syndrome, with deafness and familial autosomal recessive premature ovarian failure, has also been described.44 Sex Chromosome Abnormalities
Specific sex chromosome anomalies may be identified in some patients presenting with premature ovarian failure.45 Among them, 45,X and 47,XXY are most prevalent, followed by variable mosaicism.46 The X chromosome contains genes critical to ovarian function. It is generally believed that the Y chromosome directs the indifferent gonad toward testicular differentiation and that differentiation toward ovarian differentiation requires less specific gene activation. It is clear that both X chromosomes are required to maintain the function of the ovary. The critical region spans Xq13-26.1 Proximal deletions (Xq13-21) can be associated with primary amenorrhea while the more distal ones are associated with premature ovarian failure. Genes termed POF1 and POF2 have been localized to Xq21.3-27 and Xq13.3-q21.1, respectively.1 The age at menopause is significantly younger with the latter. Deletions in these genes are typically not associated with short stature. Within the short arm of the X chromosome, some regions have been associated with risk for premature ovarian failure. The chance of having an abnormal karyotype increases with earlier age of onset of the ovarian failure.45 A chromosomal analysis is recommended for patients younger than age 30 because of increased risk of a gonadal tumor associated with the presence of a Y chromosome.47–49 Swyer syndrome, with 46,XY chromosome compliment and a uterus, may result from a defective Y chromosome and usually presents with primary amenorrhea. The frequency of Y chromosome material detected by polymerase chain reaction is high in Turner’s syndrome (12.2%), but the occurrence of a gonadal tumor among these Y-positive patients is low (7% to 10%).50 It has been estimated that 75% of premature ovarian failure patients presenting with primary amenorrhea have a 45,X or mosaic chromosome patterns.51 Fragile X syndrome premutation carriers, typically with mental retardation and developmental delay, intention tremor, ataxia, or dementia, are at an increased risk for premature ovarian failure, with an incidence of 16% to 21%.52 A higher risk for premature
ovarian failure (28%) has been proposed for carriers inheriting the premutation from the father, compared to a 4% risk when inherited from the mother.53 Expansion of a triplet repeat within exon 1 of the FMR1 X-linked gene causes the fragile X syndrome. Expansions of between 50 and 200 repeats are premutations. Evidence suggests that female carriers of premutations in the FMR1 gene are at increased risk of premature ovarian failure. Although it is difficult to be obtain precise information, the risk has been reported to be between 22% and 26%.54
Autoimmune Etiologies Autoimmune premature ovarian failure can be isolated or part of the polyglandular autoimmune syndromes (see Table 20-1).55,56 These syndromes are associated with ovarian failure in more than 60% of patients. Polyglandular autoimmune syndrome type1 is rare, occurs before adulthood, and is inherited in an autosomal recessive manner; its components include hypoparathyroidism, mucocutaneous candidiasis, hypoadrenalism, and primary hypogonadism. The adrenal autoimmunity is directed against the side chain cleavage and the 17-hydroxylase enzymes. Polyglandular autoimmune syndrome type 2 is more common, usually occurs in adults, has a female preponderance, and has a polygenic inheritance related to HLA-DR3 and HLA-DR4; its components include adrenal insufficiency, autoimmune thyroid disease, type 1 diabetes mellitus, and gonadal failure. The adrenal defect involves antibodies to the enzyme 21-hydoxylase. A spectrum of other autoimmune disorders has been recognized in patients with premature ovarian failure, including vitiligo, myasthenia gravis, Sjögren syndrome, systemic lupus erythematosus, celiac disease, rheumatoid arthritis, and pernicious anemia. Histologic evidence of lymphocytic oophoritis has been demonstrated in 11% of patients with premature ovarian failure; 78% of these patients were positive for steroid cell antibodies, suggesting an immune-mediated insult to the ovaries.57 The lympocytic infiltration seems to spare the primordial follicles. A loss of the regulatory/suppressive CD4+ cells may be the underlying mechanism for premature ovarian failure in patients with thymic aplasia, resulting in an exaggerated autoimmune damage to various organs, including the ovary.58 Circulating immunoglobulins that inhibit the binding of FSH to its receptor have been described.59 In a prospective clinical trial of 119 women with karyotypically normal spontaneous premature ovarian failure, testing for hypothyroidism (27%) and diabetes (3%) was judged to be worthwhile. It was suggested that tests for other possible associated diseases be based on associated clinical presentation.60 Steroid cell autoantibodies seen in Addison’s disease may crossreact with the theca interna/granulosa layers of the ovarian follicles, and their presence is a marker for the association of Addison’s disease and premature ovarian failure. Steroidogenesis enzymes can be targets of autoantibodies. Three percent of women with premature ovarian failure develop adrenal insufficiency (a 300-fold increase compared with the general population). Symptoms could include anorexia, weight loss, vague abdominal pain, weakness, fatigue, salt craving, and skin hyperpigmentation. The lack of consensus on ovary-specific antibodies as markers for ovarian autoimmunity has clinical and research consequences.
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Section 3 Adult Reproductive Endocrinology Variations in detection of ovarian autoantibodies are likely to be due to study design elements such as antibody test format and antigen preparation, in addition to the multiplicity of intraovarian targets potentially involved in ovarian autoimmunity, including ovarian cellular elements and oocyte-related antigens.61 Many studies only assess one target antigen, leaving individuals with ovarian autoimmunity unidentified.
Infectious Agents A rare type of infection related to premature ovarian failure is mumps oophoritis. It appears that this aberration in menstrual function and fertility may be related to the time during which the infection occurs as well as to the severity of the infection. In addition, it is apparent that mumps oophoritis may be a more frequent cause of premature ovarian failure than commonly suspected.62,63
Iatrogenic Etiologies
supply, with resulting ischemia. Multiple procedures on the same ovary can have a negative cumulative effect. The intraovarian use of electrocautery and other tissue destruction modalities may reduce the number of viable ovarian follicles.
Environmental Toxins Smoking, among other environmental factors, has been shown to accelerate the onset of menopause by approximately 2 years.80
Idiopathic Etiologies Many women with premature ovarian failure may have none of the above etiologies. Population-based studies have suggested an association between various epidemiologic parameters and risk of premature ovarian failure. A low socioeconomic status, a higher education level and nulliparity,81 a higher body mass index and anthropometric measurements have all been proposed risk factors for developing premature ovarian failure in different populations.82
Chemotherapy
Many chemotherapeutic agents used for the treatment of malignancies are toxic to the ovaries and cause ovarian failure. Chemotherapy is associated with exaggerated attrition of ovarian follicles through alteration of DNA, direct destruction of dividing granulosa cells, and damage to the oocytes.1,64–73 These effects may be preventable, as discussed in the Management of Premature Ovarian Failure section in this chapter. Radiation
The effect of radiation depends on age and the X-ray dose.74,75 Duration of time over which exposure occurs may also be important. Steroid levels begin to fall and gonadotropins rise within 2 weeks after radiation of the ovaries. Young women exposed to radiation are less likely to have immediate and permanent ovarian failure, possibly because of the higher number of oocytes present at younger ages. The risk of premature ovarian failure can be reduced in women undergoing pelvic irradiation by laparoscopically transposing the ovaries out of the pelvis before radiation.76 The risk does not appear to be reduced by treatment with hormone modulators before irradiation.77 The sensitivity of the cells to the adverse influences is related to the nature of the agent, the dose, and the patient’s age at the time of exposure; the younger the patient, the lesser the likelihood of complete cessation of gonad function as an immediate sequel to therapy.1,78 The duration of exposure to toxic agents may also be relevant. Resumption of menses and pregnancy have been reported after radiotherapy and chemotherapy.79 Surgery
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Surgical or vascular injury to the ovary may reduce the number of available ovarian follicles. Ovarian torsion and its effects on blood supply reduction may contribute to the damage. Operative laparoscopy has become a more commonly done procedure by an increasing number of surgical specialties. Direct surgical injury to the ovarian vessels within or outside the ovary can have deleterious effects. Destruction of intraovarian lesions such as endometriomas or other ovarian cysts may reduce intraovarian regional blood
Premature Ovarian Failure and Fertility It is important to appreciate that in premature ovarian failure, despite the occurrence of amenorrhea and elevation of the FSH levels, residual oocytes may still exist, albeit in significantly diminished numbers.1 Therefore the term premature menopause is not correct. Residual follicles, when present, usually exhibit episodic function, as opposed to the virtually inert oocyte–granulosa units seen in age-appropriate menopause.83 As many as 20% of women with premature ovarian failure will exhibit sporadic ovulatory cycles.84 Indeed, pregnancies have been reported in up to 8% of patients.85
DIAGNOSIS OF PREMATURE OVARIAN FAILURE Premature ovarian failure should be suspected in any woman younger than age 40 who presents with either amenorrhea or signs of hypoestrogenemia and menstrual irregularity. These women may go through a normal puberty and a variable period of cyclic menses followed by oligomenorrhea and amenorrhea (Table 20-2). Therefore, premature ovarian failure should always be included in the differential diagnosis of anovulation.
History and Physical Examination History and physical examination may reveal symptoms and signs of estrogen deficiency, such as hot flashes and urogenital atrophy with attenuated vaginal rugae and scant cervical mucus. The underlying ovarian defect may be manifest at varying ages, depending on the number of functional follicles left in the ovaries. The different symptoms may be regarded as phases in a process similar to perimenopausal change regardless of the actual age of the patient. If loss of follicles occurs rapidly before puberty, primary amenorrhea and lack of secondary sexual development ensue. The degree to which the adult phenotype develops and when the amenorrhea occurs depend on whether follicle loss took place before, during, or after puberty.
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Chapter 20 Premature Ovarian Failure Table 20-2 Potential Clinical Symptoms and Signs of Premature Ovarian Failure
goiter should be pursued. Evaluation for neurosensory deafness and a detailed eye examination should be considered. Hyperpigmentation, postural hypotension, and vitiligo may be signs of associated adrenal disease.
Younger than age 40 Gynecologic history Irregular menses or amenorrhea Anovulation or oligo-ovulation Hot flashes Urogenital atrophy Sexual infantilism Family history Mental retardation Premature ovarian failure Personal history Autoimmune disease Mumps infection Exposure to toxic agents (radiation, chemotherapy) Associated symptoms Fatigue Weight loss Anorexia Nausea Postural dizziness and salt craving Neurosensory deafness Dry eyes
Deafness can be suggestive of Perrault’s syndrome.44 There also appears to be an association of premature ovarian failure with dry eye syndrome.86 Family history of premature ovarian failure and familial mental retardation should be obtained. The risk of FMR1 mutation in patients with premature ovarian failure and no family history is approximately 6%. In patients with a family history of premature ovarian failure the risk is higher. History of mumps infection should be obtained. Exposure to radiation, chemotherapy, tobacco products, and other environmental toxins may result in accelerated ovarian follicular loss and should be noted. All prior ovarian surgeries should be documented. Fatigue, weight loss, anorexia, nausea, postural dizziness, and salt craving may suggest adrenal insufficiency. Most patients have normal results on physical examination except for urogenital atrophy (Table 20-3). However, features of Turner’s syndrome, such as short stature, low posterior hairline, high arched palate, shield chest with widely spaced nipples, and short fourth and fifth metacarpals, should be sought. Evidence of possible associated autoimmune diseases such as ptosis and
Table 20-3 Possible Physical Findings in Premature Ovarian Failure Short stature
Laboratory Evaluation Menopausal serum FSH levels (>40 IU/L) on at least two occasions in a woman younger than age 40 are sufficient for the diagnosis of premature ovarian failure. Any woman with irregular menses for 3 consecutive months requires FSH, estradiol, prolactin, and thyrotropin measurements to rule out premature ovarian failure among other hormonal etiologies. The progestin challenge test can be misleading in the early stages of premature ovarian failure. Significant levels of circulating estradiol can be present in women with little residual ovarian function. Once premature ovarian failure is diagnosed, the patient should be evaluated for associated autoimmune disorders. Testing for antiovarian antibodies is considered to be unreliable at this time. Far more critical is testing for antiadrenal antibodies. If they are positive further testing of adrenal function is necessary (Table 20-4). The most sensitive test is the corticotropin stimulation test. Women with premature ovarian failure are at increased risk of autoimmune thyroid disease. For this reason, thyrotropin, T4, and thyroid peroxidase autoantibodies should be obtained. Other tests for autoimmune disease include a sedimentation rate, complete blood count with differential, antinuclear antibody, and rheumatoid factor. Other tests to consider under specific circumstances are a fasting glucose test to check for diabetes mellitus, calcium and phosphorus to exclude hypoparathyroidism, pregnenolone to evaluate 17-hydroxylase deficiency in sexually infantile hypertensive women, and galactose-1-phosphate to evaluate for galactosemia. A karyotype is necessary to evaluate X chromosome abnormalities and the presence of Y chromosome material. Although most cases occur before age 30, some authorities feel that all patients with premature ovarian failure should have a karyotype. Testing for premutation in the FMR1 gene would identify fragile X pedigrees. In amenorrheic women who desire fertility, FSH, LH, and estradiol should be measured weekly for a month to detect any remaining ovarian follicular activity. The lack of significant rise of estradiol or decrease of FSH suggests irreversible ovarian failure, especially in the absence of any demonstrable antral follicles on ultrasound.82 Alternatively, indirect information about the remaining ovarian reserve of follicles in women with some menstrual function may
Low posterior hairline High arched palate Shield chest Widely spaced nipples Short 4th and 5th metacarpal Absence of vaginal rugae
Table 20-4 Suggested Initial Screening Tests for Associated Medical Disorders
Ptosis
Antiadrenal antibodies (adrenal disease) If positive, screen with corticotropin stimulation test
Goiter
Fasting glucose (diabetes)
Skin hyperpigmentation
Thyrotropin T4, antithyroid antibodies (thyroid disease)
Postural hypotension
Calcium and phosphorus (parathyroid disease)
Vitiligo
Complete blood count (pernicious anemia)
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Section 3 Adult Reproductive Endocrinology be obtained by measuring day 3 FSH and estradiol,23,87–89 performing a clomiphene challenge test,90 and obtaining an ultrasonographic antral follicle count.91
Ovarian Biopsies Ovarian biopsies are not necessary for clinical care. When done as part of a research protocol in women with premature ovarian failure, ovarian biopsies show either no follicles or a small number of follicles, sometimes with lymphocytic perifollicular infiltration consistent with an autoimmune process. In patients with the resistant ovary syndrome, many small follicles are found with little progress in folliculogenesis.82
Imaging In primary amenorrhea associated with hypergonadotropic hypogonadism and sexual infantilism, the ovarian remnants may exist as streaks, and transvaginal ultrasonography usually cannot detect any ovaries. Follicular cysts and pregnancies have been demonstrated in a subset of patients with high gonadotropin levels and menstrual irregularities diagnosed with premature ovarian failure. Pelvic ultrasonography for antral follicle count has been used as an indirect indicator of ovarian follicle reserve.91 Antral follicles will appear as round or oval echo-free structures up to 5 to 10 mm in diameter. Pelvic ultrasonography will sometimes reveal remaining follicles in patients 6 years after a diagnosis.90 Bone density should be performed as a baseline and as frequently as needed thereafter. However, it is critical to understand that the results need to be interpreted in light of the patient’s age (see Chapters 24 and 25). Treatment protocols may need to be modified to ensure that osteoporosis does not become a problem.
MANAGEMENT OF PREMATURE OVARIAN FAILURE Prevention
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Probably the most important lifestyle event for primary prevention is to stop smoking. Very little can be done to prevent premature ovarian failure caused by cytogenetic or infectious etiologies. Laparoscopic transposition of ovaries out of the pelvis before radiation reduces the risk of premature ovarian failure.92,76 This risk does not appear reduced by prior treatment with hormone modulators.77 Predictable ovarian failure related to premature ovarian aging, such as with familial premature ovarian failure, may allow several preventive intervention options, most of which remain experimental at this time. For the 10% of women in the general population who are expected to become menopausal by age 45, the critical point of 25,000 resting follicles would probably be reached 13 years earlier. By age 32, these women would begin a rapid decline of fertility and possibly have total loss of fertility by age 36. In the years following the diagnosis at age 32 or younger, these women will have a reproductive potential similar to a 37-year-old woman and could experience increased incidence of dizygotic twinning,93–95 increased incidence of aneuploidy88,96 and miscarriage,89 subfertility,90,97 and a relatively poor response to ovarian stimulation.
Under this scenario of fixed time intervals between premenopausal reproductive milestones, menstrual cycles may continue to be regular for 6 to 8 more years following the diagnosis of reduced ovarian follicular reserve.9,10,16, 98–101 The diagnosis may be suspected by finding reduced antral follicle counts,18-21,87 elevated FSH on the third day of menses and after a clomiphene challenge test, and lower inhibin B levels.23,88–90 There seems to be a large overlap between basal FSH levels of older and younger women, however.102 Variants of FSH receptor genotype were associated with different basal FSH levels and variable responses to ovarian stimulation with gonadotropins. A mildly elevated basal FSH level does not necessarily mean early ovarian aging.98,103–105 Serum antimüllerian hormone has been suggested as another marker.106,107 It is hoped that “DNA fingerprints” that identify women with a genetic predisposition to early ovarian aging may become available.10 For women at risk, it is wise to advise them to complete their families as soon as possible. For socioeconomic and career priority reasons, some of these women may elect to postpone childbearing, however. The details of surgical and nonsurgical options to preserve oocytes from being prematurely lost because of chemotherapy or premature ovarian aging are presented elsewhere in this book (see Chapter 32). The surgical approach involves excising some ovarian tissue followed by variable laboratory manipulation of the tissue. The birth of a healthy child from a frozen-thawed ovarian autograft in a 32-year-old woman with Hodgkin’s disease was reported recently.107 Crucial factors in the rapid depletion of the primordial follicles observed in the transplant can be attributed to the still rudimentary technical steps of tissue harvesting, preparation, and localization of the graft. The risk of reintroducing cancer cells through the grafted ovarian tissue calls for an extremely careful selection of patients for this still experimental treatment.108 The nonsurgical approach involves the use of hormonal manipulation to halt follicle depletion related to age or chemotherapy.72,73,109–112 Nuclear cloning techniques could also generate oocytes from stem cells.113 The recently described oogonia stem cells in postnatal ovaries, if confirmed, could also open new horizons in this arena.114 The nonsurgical approach seems to be preferred by a larger number of young American women.114
Counseling Patients determined to have premature ovarian failure should receive psychological, endocrinologic, and genetic counseling regarding the implications of their disease (Table 20-5).
Fertility Prognosis Pregnancies have been reported in women with premature ovarian failure and high gonadotropin levels.115 It has been Table 20-5 Premature Ovarian Failure Patients Referred for Genetic Counseling Women with a family history of premature ovarian failure Women with premature ovarian failure and a chromosomal abnormality Women with premature ovarian failure and family history of mental retardation
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Chapter 20 Premature Ovarian Failure suggested that approximately one half of young women who have 46,XX spontaneous premature ovarian failure have ovarian follicles remaining in the ovary.116 These follicles function intermittently and unpredictably, and pregnancies can occur without intervention. At present, there are no proven therapies that will improve follicular function for these women. Premature ovarian failure patients still have a 5% to 10% chance to conceive after diagnosis.117 A randomized trial of hormone replacement in this setting showed that folliculogenesis occurred often but was less frequently followed by ovulation and even less frequently by pregnancy (up to 14%). Controlled trials have failed to demonstrate any success with any treatment in excess of the placebo.118,119 Estrogen therapy did not improve the rate of folliculogenesis, ovulation, or pregnancy.118 The clinician should inform premature ovarian failure patients that there is a small likelihood of spontaneous pregnancy. Women desirous of achieving pregnancy are still best served by donor oocytes120; an increased susceptibility to poor ovarian response exists when utilizing a related donor. It has been suggested that corticosteroid treatment may result in normalization of serum gonadotropins, increasing serum estradiol, ultrasonographic evidence of follicular growth, and conception, especially in women with premature ovarian failure associated with autoimmune disease.121 However, this treatment is considered experimental.
Hormone Replacement The diagnosis of premature ovarian failure results in multiple profound ramifications, including psychological devastation,122 multisystem effects of estrogen deprivation such as osteoporosis,123,124 cardiovascular morbidity,123,125 depression, and cognitive difficulties.126 Bone mineral density scores of approximately 1 standard deviation below the mean for age-comparable women have been demonstrated in patients with premature ovarian failure, despite taking estrogen replacement,1 with a 2.6fold increase in risk for hip fractures. A higher mortality rate in association with diminishing age of menses cessation has been reported.127 Snowdown and colleagues127 found an odds ratio (OR) for mortality of 1.95 (CI, 1.24–3.07) for women developing premature ovarian failure. The excess mortality was associated with coronary artery disease and stroke. This persists despite use of estrogen replacement, with the OR for mortality being 3.33 (CI, 1.14–9.72) for patients ever using estrogen replacement therapy. Women in specific pathophysiological subgroups of premature ovarian failure (i.e., autoimmune, X chromosome-related) may be more susceptible to vascular disease on the basis of the underlying defect that caused the premature ovarian failure. Other women with premature ovarian failure (i.e., chemotherapy- or radiationinduced) may be more prone to long-term diseases and mor-
tality by virtue of their primary disease that necessitated chemoradiation therapy. Hormone replacement therapy, as an “antidote” for aging in women, is becoming a less compelling option as results accumulate and alternative nonhormonal medications demonstrate efficacy against the common diseases of aging. The safety, dose, administration route, and appropriateness of selection criteria of hormonal and nonhormonal interventions are discussed elsewhere in this book and for the most part are applicable to premature ovarian failure. Typically these patients require higher doses, such as 100 μg estradiol transdermal patch to give a serum estradiol level of 100 pg/mL. Cyclic progesterone is also required. Alternatively, because of the relatively younger group age and the possibility of unpredictable ovulation, the use of birth control pills may be appropriate if the patient is not interested in pregnancy. Adequate calcium intake, vitamin D, and exercise should be reinforced. In general, treatment of premature ovarian failure should be directed toward its specific cause, if possible. Associated disease processes affecting other glands or tissues (such as thyroid and adrenals) should be addressed as well.
CONCLUSION Multiple etiologies can result in premature ovarian failure before age 40. Some of these lend themselves to possible fertility preservation technologies advanced over the past decade. Of all women, 10% may become menopausal by age 45 and these may have experienced an accelerated decline of fertility before age 32. These women may be considered to have early ovarian aging in spite of having menstrual function. Appropriate clinical history, ultrasound, and hormonal testing may help identify these asymptomatic patients at risk.
PEARLS ●
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Premature ovarian failure is not synonymous with premature menopause. The most common ascertainable causes of premature ovarian failure are genetic and autoimmune. Premature ovarian failure is associated with a higher risk for the occurrence of familial fragile X syndrome. It is important to exclude autoimmune disorders. Premature ovarian failure is associated with a higher probability of other autoimmune phenomena, such as autoimmune thyroid and adrenal disease. Testing for antiovarian antibodies is not indicated because of poor reproducibility of the assays. A karyotype should be obtained in women under age 40. Higher doses of hormone replacement therapy may be required because of the young age of patients.
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83. Costoff A, Mahesh VB: Primordial follicles with normal oocytes in the ovaries of postmenopausal women. J Am Geriatr Soc 23:193–196, 1975. 84. Nelson LM, Anasti JN, Kimzey LM, et al: Development of leutinized graffian follicles in patients with karyotypically normal spontaneous premature ovarian failure. J Clin Endocrinol Metab 79:1470–1475, 1994. 85. Rebar RW, Connolly HV: Clinical features of young women with hypergonadotrophic amenorrhoea. Fertil Steril 53:804–810, 1990. 86. Smith JA, Vitale S, Reed GF, et al: Dry eye signs and symptoms in women with premature ovarian failure. Arch Ophthalmol 122:251–256, 2004. 87. van Montfrans JM, van Hooff MH, Martens F, Lambalk CB: Basal FSH estradiol and inhibin B concentrations in women with a previous Down’s syndrome affected pregnancy. Hum Reprod 17:44–47, 2002. 88. Trout S, Seifer D: Do women with unexplained recurrent pregnancy loss have higher day 3 serum FSH and estradiol values? Fertil Steril 74:335–337, 2000. 89. Scott RT, Leonardi MR, Hofman GE, et al: A prospective evaluation of clomiphene citrate challenge test screening of the general infertility population. Obstet Gynaecol 82:539–544, 1993. 90. Kalantarundou SN, Nelson LM: Premature ovarian failure is not premature menopause. Ann NY Acad Sci 900:393–402, 2000. 91. Bancsi LJM, Broekmans FJM, Eijkemans MJC, et al: Predictors of poor ovarian response in in-vitro fertilization: A prospective study comparing basal markers of ovarian reserve. Fertil Steril 77:328–336, 2002. 92. Madsen B, Giudice L, Donaldson S: Radiation-induced premature menopause: A misconception. Int J Radiat Oncol Biol Phys 32:1461–1464, 1995. 93. Turner G, Robinson H, Wake S, Martin N: Dizygous twinning and premature menopause in fragile X syndrome. Lancet 344:1500, 1994. 94. Martin NG, Heath AC, Turner G: Do mothers of dizygotic twins have earlier menopause? Am J Med Genet 69:114–116, 1997. 95. van Montfrans JM, Dorland M, Oosterhuis G, et al: Increased concentrations of follicle-stimulating hormone in mothers with Down’s syndrome. Lancet 353:1853–1854, 1999. 96. Leach RE, Moghissi KS, Randolph JF, et al: Intensive hormone monitoring in women with unexplained infertility: Evidence for subtle abnormalities suggestive of diminished ovarian reserve. Fertil Steril 68:413, 1997. 97. te Velde ER, Scheffer GJ, Dorland M, et al: Developmental and endocrine aspects of normal ovarian ageing. Mol Cell Endocrinol 145:67–73, 1998. 98. te Velde ER, Dorland M, Broekmans FJ: Age at menopause as a marker of reproductive ageing. Maturitas 30:119–125, 1998. 99. van Zonneveld P, Scheffer GJ, Broekmans FJM, te Velde ER: Hormones and reproductive ageing. Maturitas 38:83–94, 2001. 100. van Zonneveld P, Scheffer GJ, Broekmans FJ, et al: Do cycle disturbances explain the age-related decline of female fertility? Cycle characteristics of women aged over 40 years compared with a reference population of young women. Hum Reprod 18:495–501, 2003. 101. Schipper I, de Jong FH, Fauser BCJM: Lack of correlation between maximum early follicular phase serum follicle-stimulating hormone levels and menstrual cycle characteristics in women under the age of 35 years. Hum Reprod 13:1442–1448, 1998. 102. te Velde ER, Scheffer GJ, Dorland M, et al: Age dependent changes in serum FSH levels. In Fauser BCJM (ed). Studies in Profertility: FSH Action and Intraovarian Regulation, vol. 6. New York, Parthenon, 1997, pp 145–155. 103. Lambalk CB: Value of elevated basal follicle-stimulating hormone levels and the differential diagnosis during the diagnostic subfertility work-up. Fertil Steril 79:489–490, 2003. 104. Baird DT: A model for follicular selection and ovulation: Lessons from superovulation. J Steroid Biochem 27:15–23, 1987. 105. de Vet A, Laven JSE, de Jong FH, et al: Antimüllerian hormone serum levels: A putative marker for ovarian ageing. Fertil Steril 77:357–362, 2002. 106. Fanchin R, Schonauer LM, Righini C, et al: Serum anti-Müllerian hormone is more strongly related to ovarian follicular status than serum inhibin B, estradiol, FSH and LH on day 3. Hum Reprod 18:323–327, 2003.
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117. van Kasteren YM, Schoemaker J: Premature ovarian failure: A systematic review on therapeutic interventions to restore ovarian function and achieve pregnancy. Hum Reprod Update 5:583–592, 1999. 118. Taylor A, Adams J, Mulder J, et al: A randomized, controlled trial of estradiol replacement therapy in women with hypergonadotropic amenorrhea. J Clin Endocrinol Metab 81:3615–3621, 1996. 119. Lieman H, Santoro N: Premature ovarian failure: A modern approach to diagnosis and treatment. Endocrinologist 7:314–321, 1997. 120. Sauer MV, Paulson RJ, Macaso TM, et al: Oocyte and pre-embryo donation to women with ovarian failure: An extended clinical trial. Fertil Steril 55:39–43, 1991. 121. Orshan SA, Furniss KK, Forst C, Santoro N: The lived experience of premature ovarian failure. JOGNN 30:202–208, 2001. 122. Conway GS: Premature ovarian failure. Curr Opin Obstet Gynecol 9:202–206, 1997. 123. Pouilles JM, Tremolliers F, Bonneu M, Ribot C: Influence of early age at menopause on vertebral bone mass. J Bone Min Res 9:311–315, 1994. 124. Joakimsen O, Bonaa KH, Stensland BE, Jacobsen BK: “Populationbased study of age at menopause and ultrasound assessed carotid atherosclerosis: The Tromso study. J Clin Epidemiol 53:525–530, 2000. 125. Shepard JE: Effects of estrogen on cognition, mood and degenerative brain diseases. J Am Pharmaceut Assoc 41:221–228, 2001. 126. Cooper GS, Sandler DP: Age at natural menopause and mortality. Ann Epidemiol 8:229–235, 1998. 127. Snowdown DA, Kane RL, Beeson WL, Burke GL, et al: Is early natural menopause a biological marker of health and aging? Am J Public Health 79:709–714, 1989.
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21
Abnormal Uterine Bleeding William W. Hurd, Geoffrey D. Towers, and Gary Ventolini
BACKGROUND AND DEFINITIONS Abnormal uterine bleeding (AUB) is among the most common diagnostic and therapeutic challenges faced by gynecologists. Complaints of AUB account for more than a third of gynecology visits.1 An indication of how difficult this problem can be to treat is that AUB remains the indication for half the hysterectomies performed in the United States. The inability to find any pathologic abnormality in 20% of these hysterectomy specimens suggests that AUB is often caused by potentially treatable hormonal or systemic conditions.2 Each gynecologist needs to develop an approach to AUB that is expedient, cost-effective, and successful. Focused evaluation and appropriate treatment depend on knowing the most likely causes of AUB and their most common presenting symptoms.
Abnormal Uterine Bleeding Terminology The following descriptive terms are often used to describe AUB: ● ●
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Definition Abnormal uterine bleeding is an all-inclusive term used to describe any uterine bleeding outside the parameters of normal menstruation that occurs during the reproductive years. It does not include bleeding that originates lower in the genital tract (i.e., the vagina or vulva). It usually does include bleeding originating from either the uterine fundus or cervix, because these causes are difficult to distinguish clinically, and should both be considered in all patients presenting with bleeding from the uterus. Abnormal bleeding can occur during childhood or after the menopause. However, because the differential diagnoses and thus the diagnostic approach are markedly different during these time periods, bleeding in these age groups is considered separately in Chapters 13 and 24.
Normal Menstruation Exactly what is considered normal menstruation is somewhat subjective and often varies between individual women and certainly between cultures. However, normal menstruation (eumenorrhea) can be defined as bleeding that occurs after ovulatory cycles every 21 to 35 days, lasts 3 to 7 days, and is not excessive. The total amount of blood lost during a normal menstrual period has been found to be no more than 80 mL, although this is difficult to estimate clinically, because much of the menstrual effluent is dissolved endometrium.3 Normal menses do not cause severe pain, do not include passage of identifiable clots, and do not require the patient to change pads or tampons more than once per hour. It follows that AUB is any bleeding that falls outside these parameters.
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Dysmenorrhea—painful menstruation Polymenorrhea—frequent menstruation with bleeding intervals shorter than 21 days Menorrhagia—excessive menstrual bleeding, in terms of flow (>80 mL) and/or duration (>7 days). This implies regular ovulatory cycles. Metrorrhagia—irregular menstruation intervals Menometrorrhagia—irregular menstruation intervals with excessive flow and/or duration Oligomenorrhea—menstruation fewer than 9 times per year (i.e., average bleeding intervals >40 days) Hypomenorrhea—very light or short duration menstruation Intermenstrual bleeding—uterine bleeding in between apparently ovulatory menses Amenorrhea —absence of menses for at least 6 months, or three cycles Postmenopausal bleeding—uterine bleeding more than 12 months after cessation of menses.
These various types of characteristic bleeding patterns can give clues as to the etiology and help guide the diagnostic workup. However, because of the marked variation in presentation and the common existence of multiple potential causes of bleeding, presentation alone cannot be used clinically to exclude common conditions. Dysfunctional Uterine Bleeding: An Obsolete Diagnostic Term
Dysfunctional uterine bleeding is a traditional term that was used for years to refer to excessive uterine bleeding in cases where no uterine pathology could be identified.4 However, the development of a greater understanding of AUB and the continuing development of more sophisticated diagnostic techniques has made this term outdated. In most cases, bleeding unrelated to uterine pathology can be determined to be due to chronic anovulation (polycystic ovary syndrome and related conditions), exogenous steroid hormones (contraceptives or hormone replacement therapy), or hemostatic disorders (e.g., von Willebrand’s disease). In many cases that would have been referred to as dysfunctional uterine bleeding in the past, modern diagnostic techniques identify uterine or systemic pathologies that (1) result in anovulation (e.g., hypothyroidism), (2) result from anovulation (e.g., endometrial hyperplasia or cancer), or (3) coexist with anovulatory bleeding but may or may not be causal (e.g., leiomyomata).
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Section 3 Adult Reproductive Endocrinology Table 21-1 Common Uterine Conditions Associated with Abnormal Uterine Bleeding Pregnancy Early normal pregnancy Spontaneous abortion Ectopic pregnancy Gestational trophoblastic disease Infection Pelvic inflammatory disease Endometritis Cervicitis
spontaneous abortion, whereas the remaining half will ultimately prove to have a viable pregnancy. Ectopic pregnancies, which currently make up 2% of all pregnancies, will commonly present with AUB as one of the symptoms as well.7 Gestational trophoblastic disease is another pregnancy-related problem that presents as AUB in more than 80% of cases.8 Pregnancy must be ruled out in every case of AUB in reproductive-age women, no matter how obvious any alternative causal diagnoses might be.
Uterine Pathology An important and expected priority for gynecologists is to precisely identify uterine pathology that might contribute to uterine bleeding (see Table 21-1). Most of these diagnoses can be determined to be related to infection and neoplasm. An additional common uterine pathology related to AUB is adenomyosis.
Neoplasms Benign Leiomyoma Endometrial polyps Endocervical polyps Malignant Endometrial carcinoma Cervical carcinoma Adenomyosis
Infection Table 21-2 Incidence of Endometrial Polyps and the Risk of Associated Malignancies as a Function of Age. Age Group (Years of age)
Incidence of Endometrial Polyps
Risk of Associated Malignancy
25–35
9%
2%
36–45
27%
11%
46–55
29%
15%
56–65
18%
17%
>65
17%
55%
Data from Hileeto D, Fadare O, Martel M, Zheng W: Age-dependent association of endometrial polyps with increased risk of cancer involvement. World J Surg Oncol 3:8, 2005.
Clinically, treatment will always be the most effective when specific causes of AUB can be identified. Because grouping widely divergent causes of AUB together in a poorly defined group is unlikely to improve diagnosis or treatment, a national consensus group has recently concluded that dysfunctional uterine bleeding no longer has any usefulness in clinical medicine.5
ABNORMAL UTERINE BLEEDING CAUSED BY UTERINE CONDITIONS Different causes of AUB can be grouped according to their basic pathophysiology (Tables 21-1 and 21-2). The clinician must keep in mind that any individual patient can simultaneously have two or more causes of uterine bleeding. For this reason, the workup must evaluate patients simultaneously for the most likely and most serious anatomic and systemic etiologies based on clinical presentation.
Pregnancy
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Normal pregnancies, spontaneous abortions, and ectopic pregnancies together represent the most common causes of AUB in the reproductive-age group. First-trimester bleeding occurs in up to 25% of all pregnancies and is associated with an increased risk of several common complications.6 In approximately half of these cases, bleeding will be an early symptom of impending
Infection is a surprisingly common cause of AUB and is often the basis of what appears to be AUB. In obvious cases of pelvic inflammatory disease (see Chapter 33), approximately 40% of the patients will present with vaginal bleeding.9 An underrecognized cause of uterine bleeding is endometritis. Although chronic endometritis was classically diagnosed only when plasma cells were found on endometrial biopsy, recent studies have found an association between AUB and reactive changes in the surface endometrium, but no association with the presence of a particular type of inflammatory cell.10 Other studies have verified that subclinical endometritis is a common finding in patients diagnosed with AUB and can be related to any of a number of pathogens.11 Cervicitis is another common cause of AUB characterized by postcoital spotting. In addition to common sexually transmitted diseases (i.e., chlamydia and gonorrhea), other vaginal flora and pathogens can be involved.12 Postcoital bleeding is the most common presenting symptom in women found to have chlamydia infections.13 Neoplasms
AUB can be a marker for gynecologic neoplasms. These neoplasms can be benign (e.g., leiomyoma, endometrial or endocervical polyps) or malignant (e.g., endometrial or cervical carcinoma). Focal intracavitary lesions account for up to 40% of cases of AUB.14 Ovarian neoplasms can indirectly cause irregular bleeding by interfering with ovulation Some of the most common neoplasms known to cause AUB are reviewed here. Leiomyomas
These benign myometrial tumors are remarkably common and by age 50 can be found in nearly 70% of white women and more than 80% of black women on ultrasonographic examination.15 However, many of these leiomyomas are subclinical, and estimates of symptomatic leiomyomas range from 20% to 40%. Menorrhagia is more likely to be related to those lying immediately adjacent to the endometrium (e.g., submucosal or intracavitary). This is in contrast to the majority of leiomyomas that are located within the wall of the uterus (intramural), immediately adjacent to the uterine serosa (subserosal), or attached to the external uterine surface by a stalk (pedunculated).
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Chapter 21 Abnormal Uterine Bleeding Endometrial Polyps
Adenomyosis
Endometrial polyps are localized overgrowths of the endometrium that project into the uterine cavity. Such polyps may be broadbased (sessile) or pedunculated. Endometrial polyps are surprisingly common in both premenopausal and postmenopausal women, and are found in at least 20% of women undergoing hysteroscopy or hysterectomy.16 The incidence of these polyps rises steadily with increasing age, peaks in the fifth decade of life, and gradually declines after menopause. Studies have found that from 5% to 33% of premenopausal women complaining of AUB will be found to have endometrial polyps.17,18 Endometrial polyps are commonly found in patients with a long history of anovulatory bleeding, suggesting that polyps might be the result of chronic anovulation in some women. Polyps are also found in women complaining of postmenstrual spotting or bleeding in ovulatory cycles or during cyclic hormonal therapy. Although endometrial polyps in premenopausal women are usually benign, the risk of associated endometrial malignancy increases significantly with age, such that in women older than age 65 the risk of malignancy is greater than 50% (see Table 21-2).16 In one pathologic study of 513 women with endometrial polyps, associated carcinomas were endometrioid in 58, serous in 6, carcinosarcoma in 1, and clear cell in 1.16
Adenomyosis is the benign invasion of endometrium into the myometrium. Microscopic examination of the uterus reveals endometrial glands and stroma deep within the endometrium surrounded by hypertrophic and hyperplastic myometrium. This histopathologic diagnosis is made on careful microscopic evaluation of uterine specimens in more than 60% of hysterectomy specimens.22 Clinically, two thirds of patients with adenomyosis will complain of menorrhagia and dysmenorrhea, and pelvic examination usually reveals a diffusely enlarged and tender uterus. Diagnostic tests that are suggestive of adenomyosis include transvaginal ultrasonography and magnetic resonance imaging (MRI). The sensitivity for ultrasonography probably approaches 50%, and the sensitivity of MRI ranges from 80% to 100%.22,23 Hopefully, more effective diagnostic tests and treatment besides hysterectomy will be developed in the future.
Endometrial Cancer
The single most important disease to identify early in the evaluation of a perimenopausal or postmenopausal woman is endometrial cancer. In women age 40 to 49, the incidence of endometrial carcinoma is 36 per 100,000.19 After the menopause, approximately 10% of women with AUB will be found to have endometrial cancer, and the incidence increases with each decade of life thereafter. Endocervical Polyps
These soft, fleshy growths originate from the mucosal surface of the endocervical canal. They usually hang from a stalk and protrude through the cervical os, although some are broad based. They usually range in size from 3 to 20 mm, but are occasionally even larger. The cause of endocervical polyps is unclear, but they are known to be more frequent in women on oral contraceptives or with chronic cervicitis. Microscopically, endocervical polyps consist of a vascular core surrounded by a glandular mucous membrane and may be covered completely or partially with stratified squamous epithelium. In some cases, the connective tissue core may be relatively fibrous. Endocervical polyps removed from women taking oral contraceptives often show a pattern of microglandular hyperplasia.20 Endocervical polyps are relatively common in sexually active women and are rare before menarche. Many endocervical polyps are asymptomatic and are discovered incidentally on visual examination of the cervix. When symptomatic, these polyps usually manifest as intramenstrual or postcoital spotting. Cervical Cancer
As many as 17% of women presenting with postcoital spotting will be found to have cervical dysplasia; 4% will have invasive cancer.21 In the absence of a visible lesion, Papanicolaou smears and colposcopy (if indicated) are important diagnostic tools. In the presence of a visible cervical lesion, biopsy is the most important technique for confirming the clinical diagnosis.
ABNORMAL UTERINE BLEEDING UNRELATED TO UTERINE PATHOLOGY Many women experience heavy or irregular menstrual bleeding that is not caused by an underlying anatomic abnormality of the uterus. Although anovulatory bleeding is one of the most common underlying causes, a number of other unrelated causes, such as exogenous hormones and bleeding disorders, must also be considered (Table 21-3).
Table 21-3 Causes of Abnormal Uterine Bleeding Unrelated to Uterine Pathology* Exogenous hormones Hormone contraceptives Hormone replacement therapy Ovulation defects Physiologic oligo-ovulation Perimenarchal Perimenopausal Polycystic ovary syndrome Hyperandrogenic states Congenital adrenal hyperplasia, adult-onset Cushing’s syndrome Ovarian and adrenal tumors Systemic diseases that interfere with ovulation Hypothyroidism Hyperprolactinemia Renal failure Liver disease Endometrial atrophy Menopause Premature ovarian failure Hypogonadotropic hypogonadism Exogenous progestins Hyperandrogenemia Coagulopathy Hereditary bleeding disorders Von Willebrand disease Disorders of platelet function and fibrinolysis Acquired bleeding abnormalities Idiopathic thrombocytopenia purpura Leukemia Aplastic anemia Anticoagulation therapy *Referred to as “dysfunctional uterine bleeding” in the past.
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Section 3 Adult Reproductive Endocrinology Exogenous Hormones Hormonal therapy has become one of the most common causes of AUB. Irregular bleeding is one of the most common symptoms in women receiving contraceptive therapy and hormone replacement therapy (HRT) and is the most common reason for discontinuation of these therapies. Hormone Contraceptives
Today, approximately 10 million women in the United States use some type of hormonal contraception, including combination oral contraceptives, progestin-only pills, depot medroxyprogesterone acetate injections, progestin-containing intrauterine devices, subdermal levonorgestrel implants, transdermal combination hormone patches, and intravaginal rings (see Chapter 26). In addition to being a common reason to visit primary care physicians, AUB is a major cause of contraception discontinuation and subsequent unplanned pregnancy. During the first 3 months of combination oral contraceptive use, as many as one third of women will experience AUB. For the majority of women, the most effective treatment approach is patient reassurance and watchful waiting. As the uterus adapts to the new regimen of hormonal exposure, the monthly withdrawal bleeding becomes regular, lighter, and less painful than natural menstruation in most women. If abnormal bleeding persists beyond 3 months, other common causes should be excluded. In young sexually active women, sexually transmitted diseases should be excluded; in one study, almost one third of women on oral contraceptives who experienced abnormal bleeding were found to have otherwise asymptomatic Chlamydia trachomatis infections.24 If no cause for AUB other than hormonal therapy is found, treatment options include the use of supplemental estrogen and changing to an oral contraceptive with a different formulation with a different progestin or higher estrogen content (see Chapter 26). Women using progestin-only contraceptives have an even greater risk of continued AUB than those using combined oral contraceptives. Prolonged exposure to progestins results in a microscopic condition sometimes called pseudoatrophy (see Endometrial Atrophy in this chapter). When reassurance is not sufficient, administration of supplemental estrogen during bleeding episodes is sometimes useful. Hormone Replacement Therapy
300
Hormone replacement therapy (HRT) after the menopause is a common iatrogenic cause of AUB. Unopposed daily estrogen therapy is associated with the highest rates of irregular bleeding and subsequent discontinuation of therapy.25 The addition of sequential or continuous oral progestins is associated with decreased irregular bleeding and reduced rate of endometrial hyperplasia. Sequential progestins result in the lowest rate of irregular bleeding during the first year of therapy, but the rate for sequential and continuous therapy is similar thereafter. Each selective estrogen receptor modulator (SERM) is associated with a distinctive risk of AUB, which varies according to their effect on the endometrium. Tamoxifen, the first SERM used clinically as adjuvant treatment for breast cancer, exhibits antiestrogenic activity in the breast but stimulates the endometrium.26 As a result, tamoxifen has an incidence of postmenopausal vaginal bleeding similar to unopposed estrogen and likewise
increases the risk of endometrial pathology, including endometrial polyps, hyperplasia, and cancer. Raloxifene, a SERM approved for the prevention of osteoporosis, has little if any estrogenic effect on the uterus, resulting in atrophic endometrium.27 As a result, the risk of vaginal bleeding for women taking raloxifene is not increased compared to women not taking any form of HRT.
Ovulation Defects Abnormal or absent ovulation is one of the most common causes of AUB during the reproductive years. A brief description of normal menstrual physiology (which is covered in depth in Chapter 1) is helpful in understanding anovulation as an underlying cause of AUB. Normal Menstruation
Each month, the endometrium of normally ovulating women is exposed to physiologic levels of estradiol (50 to 250 pg/mL) accompanied for the last 14 days of each cycle by progesterone (midluteal phase >12 nmol/L). The result is a structurally stable endometrium 5 to 20 mm thick as measured by transvaginal ultrasound. Withdrawal of progesterone and estrogen results in menstruation, which involves the breakdown and uniform shedding of much of the functional layer of the endometrium, which is enzymatically dissolved by matrix metalloproteinases.28 Normal menses occur every 28±7 days, with duration of flow of 4±2 days and a blood loss of 40±40 mL.29 Hemostasis is achieved by a combination of normal coagulation mechanisms and vasoconstriction of the spiral arterioles. Oligo-ovulation and Anovulation
Irregularity or absence of ovulation is surprisingly common among reproductive-age women not using hormonal contraception. In the perimenarchal years, adolescents often have a number of anovulatory cycles as part of the maturation process, but only occasionally do they complain of clinically significant AUB. In the years immediately preceding menopause, anovulatory cycles again become more common for many women. These episodes of endometrial exposure to unopposed estrogen increase the risk of not only AUB, but also endometrial hyperplasia and endometrial cancer. During the intervening years, both chronic and intermittent intervals of anovulation can occur, often as the result of treatable underlying conditions. Mechanism of Anovulatory Bleeding
Anovulation results in AUB as a result of chronic exposure of the endometrium to estrogen without the benefit of cyclic exposure to postovulatory progesterone. Endometrium thus exposed to unopposed estrogen becomes abnormally thickened and structurally incompetent. The result is asynchronous shedding of portions of the endometrium unaccompanied by vasoconstriction. The bleeding associated with unopposed estrogen exposure is often heavy. Because the blood has not been lysed by endometrial enzymes, blood clots are often passed, resulting in increased menstrual cramping in many women. Prolonged periods of bleeding also appear to predispose to subclinical endometritis, which exacerbates bleeding further and is often unresponsive to hormonal therapy.
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Chapter 21 Abnormal Uterine Bleeding Polycystic Ovary Syndrome
The most common causes of chronic anovulation are grouped together under a constellation of symptoms referred to as polycystic ovary syndrome (PCOS) (see Chapter 15). PCOS is a heterogeneous endocrine and metabolic disorder that affects 6% to 10% of reproductive-age women.30 This syndrome is diagnosed when a woman without an underlying condition is found to have two out of the following three criteria: (1) oligo-ovulation or anovulation, (2) hyperandrogenism and/or hyperandrogenemia, and (3) polycystic ovaries.31 These women have circulating estrogen levels in the normal range but anovulatory progesterone levels. Polycystic ovary syndrome is often the result of insulin resistance.30 In today’s culture, insulin resistance is often related to obesity. However, not all women with PCOS have insulin resistance and obesity. Insulin resistance is a common but not universal metabolic disorder underlying PCOS.32 The mechanism whereby insulin resistance results in PCOS is fascinating.33 Insulin increases production of androgens by both the ovaries (primarily androstenedione and testosterone) and adrenal gland (primarily dihydroepiandrosterone). In the ovary, insulin increases androgen secretion by thecal cells in an LHdependent process and ovarian stroma cells. These increased androgens contribute to the hirsutism and may contribute to the increased body mass often seen in PCOS patients. These androgens can be aromatized peripherally in both fat and muscle to estrogens (primarily estrone), which acts on the pituitary to increase secretion of LH, which in turn stimulates the ovaries to secrete more androgens in concert with insulin. The resulting positive feedback loop is believed to be the cause of many cases of PCOS. The accuracy of this interpretation is supported by the observation that in many overweight patients, either weight loss or the use of an insulin-sensitizing agent (e.g., metformin) will simultaneously improve insulin resistance and restore regular ovulatory cycles.33 Systemic Diseases That Can Mimic PCOS
Some patients who are oligo-ovulatory or anovulatory have an underlying systemic disease, and these patients can be clinically indistinguishable from PCOS. Although some diseases can be detected with appropriate testing, not all of these systemic conditions can be treated such that the symptoms of PCOS completely resolve. Conditions that can result in signs and symptoms identical to PCOS can be divided into two groups. The first group includes conditions that cause hyperandrogenemia, which can in turn interfere with ovulation and result in a clinical picture identical to PCOS.34 These include adult-onset congenital adrenal hyperplasia, Cushing’s syndrome and disease, and androgen-secreting neoplasms of the ovary or adrenal gland. Adult-onset congenital adrenal hyperplasia should be suspected whenever PCOS symptoms occur simultaneously with menarche. Cushing’s and androgen-secreting tumors should be suspected when hyperandrogenism and ovulation dysfunction present rapidly in a woman with previously normal menstrual cycles. Evaluation and management of these specific syndromes are discussed in Chapters 18 and 22. The second group consists of any systemic condition that can interrupt ovulation. Both hypothyroidism and hyperprolactinemia are relatively common conditions that may have no symptoms other than interference with ovulation. Simple blood tests can
screen for these conditions in the initial evaluation of apparent PCOS. In addition, any serious systemic disease can interfere with ovulation—most notably, renal failure and chronic liver disease. Both of these systemic disorders can affect hemostasis. Patients with serious systemic diseases usually manifest significant symptoms in addition to ovulatory dysfunction and AUB.35
Endometrial Atrophy Endometrial atrophy from any cause can result in AUB, usually described as spotting. The significance of this type of AUB is that it is indistinguishable from the earliest symptoms of endometrial cancer and thus must be carefully evaluated in the perimenopausal and postmenopausal woman. Hypoestrogenemia most commonly occurs as a result of surgical or natural menopause. Although natural menopause occurs at an average age of approximately 51 years, 2% of women undergo premature menopause before age 40 years. Hypoestrogenemia also occurs in women with normal ovaries who lack gonadal hormonal stimulation because of pituitary or hypothalamic pathology, descriptively grouped together as hypogonadotropic hypogonadism. Causes of this condition include hypothalamic amenorrhea, usually secondary to conditions such as anorexia nervosa, repetitive or prolonged strenuous exercise, or starvation, and the relatively uncommon pituitary failure. Hypoestrogenemia can also be secondary to hyperprolactinemia. Histology
Histologically, hypoestrogenemia leads to atrophy of both endometrial glands and stroma. Scanty, small glands are seen in dense stroma. The result is thin endometrium less than 5 mm thick on transvaginal ultrasonography. Prolonged exposure to exogenous progestins, with or without estrogen, can also result in endometrial atrophy. Long-term use of combination oral contraceptives results in poorly developed glands lined by a single layer of low columnar to cuboidal cells. Secretory changes are minimal, but stromal decidualization is present; the result is discordance between small inactive glands and decidualized stroma. Numerous granular lymphocytes are often present. Progestin-only contraception results in endometrial atrophy with sparse, narrow glands lined by flattened epithelium in a spindle-cell stroma but no decidual reaction. Women with hyperandrogenemia can develop a similar clinical and histologic picture.
Coagulopathy A surprisingly common cause of menorrhagia is one of several inborn or acquired conditions that interfere with normal hemostatic mechanisms in the case of vascular interruption. Hereditary Bleeding Disorders
Von Willebrand’s disease and less common disorders of platelet function and fibrinolysis are characterized by excessive menstrual bleeding that begins at menarche and is usually regular. As many as 20% of adolescents who present with menorrhagia significant enough to cause anemia or hospitalization have a bleeding disorder, and thus should undergo an evaluation for coagulopathy. However, it is important to remember that most AUB in this age group is probably due to anovulation.36
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Section 3 Adult Reproductive Endocrinology The most common bleeding disorder is von Willebrand’s disease, which affects 1% to 2% of the population.37 This hereditary deficiency (or abnormality) of the von Willebrand factor (vWF) results in decreased platelet adherence. Von Willebrand factor interacts with platelets to form a platelet plug. A fibrin clot will then form on this plug. There are three main types of von Willebrand’s disease. The mild form (type 1) is responsible for more than 70% of cases and is an absolute decrease in the protein. The mechanism by which an abnormal factor leads to bleeding at the level of the endometrium is unclear. The vast majority of women with von Willebrand’s disease report AUB, specifically menorrhagia. The prevalence of this disorder in adult women with menorrhagia can range from 7% to 20%. Other inherited conditions include thrombocytopenias and rare clotting factor deficiencies (e.g., factor I, II, V, VII, X, XI, XIII deficiencies). Acquired Bleeding Disorders
New onset of extremely heavy menses not amenable to hormonal therapy can sometimes be related to acquired bleeding abnormalities causing accelerated platelet destruction, such as idiopathic thrombocytopenic purpura (ITP), hematologic diseases affecting platelet production, such as leukemia, or hematologic diseases affecting platelet function (thrombocytopathies). Other systemic disorders such as sepsis and liver disorders can also cause an acquired hemostatic disorder resulting in bleeding. Anticoagulant Therapy
Excessive bleeding can sometimes be a significant problem for woman taking anticoagulant therapy, such as warfarin or heparin. Fortunately, most women taking anticoagulants do not have problems with AUB, which is considered to be an adverse reaction to anticoagulant therapy. Life-threatening genital bleeding in women taking anticoagulants is rare but may require emergency hysterectomy.38
CLINICAL EVALUATION OF ABNORMAL UTERINE BLEEDING When evaluating a woman with AUB, the workup should be tailored according to age and presentation in order to be the most expedient and cost-effective (see Table 21-1). At the same time, the clinician must be aware of common causes of AUB that might not be clinically obvious but still must be excluded. An important fact to keep in mind is that AUB can often have more than one cause. Sometimes subtle comorbid conditions, such as anovulation and secondary endometritis, make singlefactor therapy surprisingly ineffective.11 In other women, obvious causes of chronic anovulation can be associated with endometrial hyperplasia and/or cancer. Careful evaluation of the patient for multiple simultaneous causes of AUB is requisite.
History
302
A careful history is the most important factor in determining the appropriate diagnostic approach. This should include the usual and recent menstrual patterns, the extent of recent bleeding, sexual activity, and contraception. A personal or family history of a bleeding disorder should be documented. Important questions include symptoms of pregnancy, infection, changes in body hair, excessive bleeding, and systemic disease. Current medication
and information about previous Pap smears are also important. The review of systems should include subtle symptoms of systemic disease, such as weight gain or loss, abdominal swelling, somnolence, and nipple discharge. Pregnancy
In reproductive-age women, the presence of signs and symptoms of pregnancy is important to ascertain. Current contraceptive methods and past pregnancy history are likewise important. Characterization of Bleeding
Once pregnancy is excluded, the amount and character of the bleeding is the most important information. Careful, stepwise retrospective questioning will usually give a clear picture of the bleeding pattern over the previous days, months, and even years. In nonemergency cases, the use of a prospective menstrual calendar is an excellent way to document the problem as well as the response to therapy (Fig. 21-1). It is important to determine when the bleeding problems were first noticed, because menorrhagia starting at menarche should alert the clinician to the possibility of an underlying bleeding disorder. The amount of bleeding is probably the most difficult to determine, because normal or heavy menstrual bleeding can be very subjective. For research purposes, menorrhagia can be
Year:
Menstrual Cycle Record
Month: Day:
Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 Enter appropriate letter in proper calendar day square:
Figure 21-1
Menstrual calendar.
S = Spotting B = Bleeding T = Pill taken
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Chapter 21 Abnormal Uterine Bleeding defined as a monthly blood loss of more than 80 mL on three consecutive menses as measured by the alkali hematin method.39 Unfortunately, this type of accurate evaluation is neither costeffective nor readily available. Clinically, menorrhagia can be defined as bleeding on the heaviest day requiring changing soaked sanitary pads or tampons more than once every 2 hours, or using more than one sanitary pad at a time. The presence and size of blood clots passed vaginally is important, because normal menstrual effluent is made up of dissolved endometrium and nonclotting blood. Another objective measure of the problem is the amount of days lost from school or work over the past several months.
testosterone and DHEAS. All women older than age 40 should have an endometrial biopsy after pregnancy is excluded to detect endometrial hyperplasia or cancer. Polycystic ovary syndrome and adult-onset congenital adrenal hyperplasia may sometimes be indistinguishable by clinical presentation, with both disorders often characterized by hirsutism, acne, menstrual abnormalities, and infertility.41 Unfortunately, no discriminatory screening test exists for this heterologous condition, most commonly caused by 21-hydroxylase or 11β-hydroxylase deficiency. If ovulation dysfunction and signs of androgen excess begin at the time of puberty, these women should be investigated appropriately (see Chapters 18 and 22).
Symptoms of Hemostatic Disorders
Hemostatic Disorders
In adolescents with menorrhagia, it is important to determine any past history of excess bleeding during surgical, dental, or obstetric procedures because this has been found to be predictive of von Willebrand’s disease.40 Surprisingly, in this same study epistaxis and easy bruising were not clearly discriminatory symptoms.
Patients with the new onset of significant menorrhagia should be evaluated for bleeding disorders with prothrombin time, activated partial thromboplastin time, and bleeding time.42 Any patient with a history of menorrhagia since menarche, especially with a history of surgical- or dental-related bleeding or postpartum hemorrhage, should be evaluated for hereditable bleeding disorders. These tests will include specific tests for von Willebrand’s disease such as vWF antigen, vWF functional activity (ristocetin cofactor activity), and factor VIII level. These levels can fluctuate; therefore, the tests should be repeated if clinical suspicion is high. Normal ranges should be adjusted for the observation that vWF levels are 25% lower in women with blood type O compared with other blood groups. Some centers offer a screening test referred to as a “platelet function assay” before performing detailed von Willebrand testing. Further studies such as platelet aggregation studies may be required.42 If these studies are negative, factor XI level and euglobulin clot lysis time can be evaluated.
Physical Examination The physical examination is intended to detect both gynecologic and systemic diseases. Special care should be taken to document the presence of hirsutism, acne or other signs of excess androgens, and galactorrhea. The pelvic examination begins with a speculum examination to inspect the cervicx for polyps or for signs of infection or inflammation. A bimanual examination is important to determine uterine size, adnexal masses, and the presence and character of any tenderness.
Laboratory Testing Laboratory evaluation is an important part of the initial evaluation of all patients with AUB (Table 21-4). However, rather than ordering every possibly helpful test at the first visit, laboratory tests should be obtained in a stepwise fashion based on presentation (see Fig. 21-1). The most important test for all reproductive-age women complaining of AUB is a β-human chorionic gonadotropin (hCG) test for pregnancy. For all but the most insignificant bleeding, a complete blood count (CBC), including platelets, is important to detect significant anemia and disorders of platelet production or survival. Unless precluded by extremely heavy bleeding, a Pap smear should be performed on any woman who has not had one within the past year. For patients with apparent oligoovulation or anovulation, thyrotropin and prolactin will detect subtle pituitary function disorders in which AUB might be seen as the earliest symptom. Because cervical and uterine infections are common, cervical tests for gonorrhea and chlamydia are helpful in women with intermenstrual spotting, as well as in any woman at risk for these infections. Several patient groups will require additional ancillary tests. Obese patients with apparent AUB are at increased risk for Type 2 diabetes. Several authors recommend measurement of hemoglobin A1c (HbA1c) as a good diabetes screen that does not require fasting or a return visit for a provocative test. Patients with hirsutism or other evidence of androgen excess should be screened for ovarian and adrenal malignancies with total
Table 21-4 Laboratory Testing for Abnormal Uterine Bleeding All patients Pregnancy test Complete blood count (including platelets) Papanicolaou smear Cervical tests for gonorrhea and chlamydia Anovulation Thyrotropin Prolactin Obesity Type 2 diabetes screen: HgA1c Hirsutism Testosterone Dihydroepiandrosterone sulfate Over age 40 Endometrial biopsy New-onset menorrhagia40 Prothrombin time Activated partial thromboplastin time Bleeding time Menorrhagia since menarche40 Above plus: Iron profile Serum creatinine Factor VIII level vWF antigen Ristocetin cofactor Platelet aggregation studies If the above are negative, consider: Factor XI level Euglobulin clot lysis time
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Section 3 Adult Reproductive Endocrinology Malignancies and Premalignancies Endometrial Biopsy
The incidence of endometrial carcinoma in women between ages 40 and 49 has been reported to be as high as 36 per 100,000.43 The risk after menopause continues to increase. For this reason, once pregnancy has been excluded, an endometrial biopsy should be obtained in all women older than age 40 who present with AUB.
Imaging and Hysteroscopy Before the past two decades, our ability to determine the size of the uterus and visualize the uterine cavity was limited. In addition to the bimanual pelvic examination, the only other available methods were hysterosalpingogram (HSG) and dilation and curettage (D&C). Although the radiation exposure and discomfort associated with HSG are both acceptable, this technique effectively identifies only marked abnormalities of the uterine cavity. Lesions less than 1 cm in size are often missed. Likewise, the previously blind procedure of D&C gave the operator only the roughest idea of the depth and contour of the uterine cavity. Intrauterine findings at the time of hysterectomy were often a surprise. In obese patients in whom bimanual examinations are difficult, unexpected ovarian masses at laparotomy were commonplace. Transvaginal Ultrasonography
Today, transvaginal ultrasonography and sonohysterography has made unexpected findings at surgery rare (see Chapter 30). Ultrasonography and sonohysterography have become an important step in the evaluation of AUB (Fig. 21-2). Transvaginal ultrasonography can accurately determine uterine size and configuration, and can reveal the nature of both palpable and nonpalpable adnexal masses. Knowledge before surgery about the size and location of leiomyoma and the potential that an ovarian mass might be malignant is invaluable. Sonohysterography can be used to accurately visualize most intrauterine abnormities once pregnancy has been excluded. Accurate evaluation of the uterine cavity is of the greatest importance for the evaluation and treatment of AUB. This almost painless procedure involves injection of sterile saline into the uterus while a transvaginal sonogram is performed. When the uterine cavity is distended with saline, intracavitary lesions (e.g., polyps, fibroids, cancer) as small as 3 mm can be clearly seen. Office Hysteroscopy
Office hysteroscopy (see Chapter 42) is another excellent outpatient method for visualizing the uterine cavity. The discomfort and risk is also somewhat greater than with sonohysterography, and the procedure can be difficult in the presence of cervical stenosis or when the cervix is difficult to visualize. However, the color photographs of the lesion can be very instructive for patients.
MANAGEMENT OF ABNORMAL UTERINE BLEEDING Treatment of AUB Unrelated to Pregnancy or Uterine Pathology 304
When pregnancy or a uterine condition is found to be the cause of AUB, specific treatment options are required that are
described in other chapters. In more than half the cases, it will be determined that the bleeding is unrelated to pregnancy or uterine abnormalities. Treatment for these cases consists of correcting any underlying systemic abnormalities when possible and returning the endometrium to a functional status with exogenous hormone therapy when necessary. The simplest case might be hypothyroidism, where simple thyroid hormone replacement will restore normal ovulation in most cases (see Chapter 22). Hyperprolactinemia requires careful evaluation and monitoring (see Chapter 22). In some cases, what appears clinically as PCOS is actually an adrenal enzyme deficiency that can be treated with steroid replacement (see Chapter 22). As noted below in the section “Ovulation Induction,” even idiopathic PCOS can often be treated as a systemic condition related to insulin resistance. Treatment of Women with Coagulopathy
Women with von Willebrand’s disease who complain of menorrhagia can often be successfully treated with long-term oral contraceptive therapy.43 Other medical treatments used by hematologists for acute episodes include desmopressin acetate, antifibrinolytic agents, and plasma-derived concentrates of vWF.43
Emergency Treatment of Anovulatory Bleeding The most important aspect of management of anovulatory bleeding is the expedient cessation of bleeding. The first objective of all therapy is to achieve structural stability of the endometrium as quickly as possible. In women who do not desire pregnancy, the next goal is to promote universal, synchronous endometrial shedding at regular intervals or stop menstruation altogether. These goals are accomplished with some combination of estrogen and/or progestin given parenterally or orally according to the patient’s medical condition. Hemodynamic Stabilization
Some patients will present with life-threatening uterine bleeding. Although hemorrhagic shock is uncommon secondary to AUB, critically low hemoglobin levels are not, especially in perimenopausal or postmenopausal women at increased risk for cardiac symptoms secondary to severe anemia. Concurrently with establishing that bleeding is unrelated to pregnancy or an anatomic pathology, the hemodynamically unstable patient should be resuscitated with intravenous fluids and blood replacement as indicated. Expedient Evaluation
After appropriate laboratory tests (i.e., CBC and β-hCG) have been obtained, the most important part of the initial evaluation is transvaginal ultrasonography. If sonohysterography is attempted, it is important to remember that intrauterine clots are often impossible to differentiate from anatomic lesions such as leiomyoma or polyps. An endometrial biopsy is another important part of the evaluation in all women over age 40 unless an emergency D&C is planned. However, hormonal therapy does not have to be delayed until histologic diagnosis has been made. Dilation and Curettage
In cases where massive uterine bleeding is life-threatening, D&C is the most expedient way to stop blood flow and determine the
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Chapter 21 Abnormal Uterine Bleeding History and Physical
Intial lab evaluation: • CBC, platelet count • β-hCG • Pap smear
Transvaginal ultrasonography Sonohysterography
Pregnancy
Transvaginal ultrasonography
Endometrial pathology
• Viable • Spontaneous abortion • Ectopic • Molar
• Biopsy • Hysteroscopy
Cervical lesion
Myometrial pathology: • Leiomyoma • Adenomyosis
Normal uterus
Biopsy
Taking hormonal therapy
Regular menses (assume ovulatory)
Irregular menses (anovulatory)
Intermenstrual spotting
Excessive menses
Lab evaluation: • Chlamydia • Gonorrhea
Lab evaluation: • Bleeding disorders
Lab evaluation: • Thyrotropin • Prolactin • Hemoglobin A1c Signs of androgen excess: • Testosterone (total) • DHEAS
Endometrial biopsy if >40 years old Figure 21-2
Algorithm for evaluating women with abnormal uterine bleeding.
existence of endometrial pathology when present. The disadvantage of this surgical approach is risk of anesthesia, which is dependent on the patient’s overall medical condition, and the small surgical risk. Although cost should always be a consideration in modern medicine, the usually fast and effective resolution of bleeding often allows discharge within 24 hours. Thus, the cost of surgery may actually be less than the cost of several days’ hospitalization required for the medical treatment discussed in the following. However, D&C has no long-term therapeutic effect; therefore, long-term treatment must be initiated. In most cases of AUB, medical management can be safely used as the first line of treatment.
Intravenous Estrogen Therapy
In many cases where the bleeding is not dangerously brisk, it can be improved overnight by administration of intravenous conjugated estrogens, 25 mg given every 4 hours until bleeding stops. When studied in adolescents, it was found that intravenous conjugated estrogen therapy stopped acute bleeding in 90% of cases.36 Those that do not show signs of improvement in their bleeding within 8 hours required D&C. This therapy might seem paradoxical for use in anyone who is bleeding because of prolonged unopposed estrogen effect on the endometrium. However, its effectiveness has been demonstrated in a well-designed study. In theory, estrogen acutely
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Section 3 Adult Reproductive Endocrinology Table 21-5 “Taper” Oral Contraceptive Therapy for Abnormal Uterine Bleeding* Day
Frequency
1–2
One tablet 4 times daily
3–4
One tablet 3 times daily
5–19
One tablet daily
20–25
Expect menses
26
Start oral contraceptives at standard dosage
devices, nonsteroidal anti-inflammatory drugs (NSAIDs), and danazol. In Europe, tranexamic acid, an antifibrinolytic agent, has been used to treat many women with AUB. It has been reported to be very effective in a recent Cochrane Review. Now considered to be the treatment of choice for menorrhagia in Europe, it is given during the first 5 days of menses. The original worry that it would increase thromboembolic risk has not been confirmed. Another antifibrinolytic that has been used effectively is aminocaproic acid. Finally, gonadotropin-releasing hormone (GnRH) analogues can also be used on a temporary basis.
*Regimen for low-dose (30 mcg ethinyl estradiol), monophasic oral contraceptives
Endometrial Synchronization
decreases uterine bleeding related to asynchronous shedding by stimulating clotting at capillary level and promoting vasoconstriction of spiral vessels. This therapy is often associated with nausea, and intravenous or oral antiemetics (oral or intravenous promethazine [Phenergan], 10 mg) should be given simultaneously. Oral High-Dose Combined Hormonal Therapy
Once bleeding has slowed to that consistent with heavy menses or less, “taper” therapy with oral contraceptives can be started (Table 21-5). This approach is also ideal for women with heavy bleeding who do not require hospitalization for stabilization and observation. Like the intravenous estrogen therapy, nausea is a common problem with this treatment and should be treated preemptively with oral antiemetics to optimize compliance. Women at Increased Risk for Cardiovascular Disease or Venous Thrombosis
It is well appreciated that estrogen-containing oral contraceptives are relatively contraindicated in any women at increased risk for cardiovascular disease or venous thrombosis. This includes women with a history of thromboembolic disease and woman over age 35 who have additional risk factors (e.g., cigarette smoking, hypertension, diabetes). Although no studies have been published using short-term, high-dose intravenous or oral estrogen in these patients, at least one case of fatal pulmonary thromboembolism has been reported with intravenous therapy.44 Certainly, highdose estrogen therapy should be used in these patients only if the benefits outweigh the risks.
Long-term Treatment of AUB
306
Effective long-term medical therapy for AUB can sometimes be difficult. Two approaches are discussed that might improve the medical therapy: synchronization of the endometrium at the beginning of therapy and diagnosis and treatment of subclinical endometritis. The long-term approach chosen for treatment for AUB depends on the underlying condition being treated and the woman’s reproductive desires. For anovulatory women wishing to become pregnant, ovulation induction is usually the most appropriate treatment. Women who do not desire pregnancy can use lowdose oral contraceptives. If contraception is not required, cyclic progestins can be used for the first 14 days of each month. For women who are ovulatory but have heavy or prolonged menses, both hormonal and nonhormonal therapy is available. In addition to oral contraceptives and cyclic progestins, some women will have excellent responses to progestin-containing intrauterine
In women with chronic irregular bleeding, it is helpful to synchronize the entire endometrium prior to starting cyclic hormones. This may reduce breakthrough bleeding with subsequent therapy. Two approaches for this can be used. A relatively safe method is the use of the potent progestin medroxyprogesterone in a dose of 10 mg/day for a full 14 days. This will usually abate the presenting bleeding episode within 2 to 3 days, and help decrease the endometrial height before withdrawal bleeding. Alternatively, “taper” therapy with oral contraceptives can be used for women presenting with heavy, prolonged bleeding. The patient should be advised that she might have moderately heavy bleeding within 1 to 2 days of stopping the medroxyprogesterone. Oral contraceptives should be started on the Sunday after this withdrawal bleeding. Iron supplementation should also be started in any patient with anemia. The patient should also be cautioned that occasional breakthrough bleeding is to be expected during the first 3 months of oral contraceptive use or if a pill is missed or taken late. Subclinical Endometritis
It has been recently observed that the most frequent histologic finding in endometrial biopsies of women with AUB is chronic endometritis.45 This suggests that when apparently anovulatory AUB does not respond to progestin withdrawal, subclinical endometritis might be a coexisting disorder that must be addressed. Although few studies have evaluated the role of subclinical endometritis in AUB, several have suggested a relationship. In one study, 81% of patients with irregular bleeding or vaginal discharge had positive endometrial cultures for Mobiluncus, and treatment with metronidazole resolved their irregular bleeding.46 In another study of 100 hysterectomies performed for irregular bleeding or fibroids, 25% of the endometrial cavities were found to harbor organisms, including Gardnerella vaginalis, Enterobacter, and Streptococcus agalactiae.47 Finally, a study of college-age women presenting with abnormal bleeding while on oral contraceptives found that 29% were infected with Chlamydia.48 Together, these data suggest that subclinical endometrial infections might play a role in many women with AUB. Cervical evaluation for common pathogens (i.e., chlamydia and gonorrhea) followed by specific therapy is important. In women with negative cultures who do not respond to cyclic hormonal therapy, empiric therapy with a broad-spectrum antibiotic (e.g., metronidazole or a cephalosporin) might also be reasonable, although prospective studies remain to be performed. Ovulation Induction
When fertility is desired, restoration of ovulation is paramount. This can be accomplished in many cases by restoring the hormonal
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Chapter 21 Abnormal Uterine Bleeding milieu to a more normal state. In the case of hyperprolactinemia, lowering prolactin levels with the use of a dopamine agonist will often result in ovulation and pregnancy (see Chapter 22). In the case of PCOS, recent studies have demonstrated that lowering insulin levels with an insulin-sensitizing drug (e.g., metformin hydrochloride) will often restore ovulation and result in pregnancy in many cases (see Chapter 37). While waiting for these therapies to result in resumption of ovulation and normal menses, monthly induction of withdrawal bleeding with oral progestin is important to avoid continued AUB. In women not using contraceptives, the use of micronized progesterone (100 to 200 mg daily for 14 days) will result in reasonable withdrawal bleeding and be safe should pregnancy occur. For patients who do not resume ovulation with systemic therapy, induction of ovulation is attempted using clomiphene citrate or injectable medications as required (see Chapter 37). Oral Contraceptives
Combination oral contraceptives have been used for decades to decrease both the duration and amount of menstrual flow and dysmenorrhea.49 More recently, it has been found that extending the number of consecutive days of active pills could decrease the annual number of menses, thus minimizing menstrual-related symptoms even further.50 A consequence of this is the marketing of extended-cycle oral contraceptives that have 3 months of active pills instead of 3 weeks and thus extend the time between menses, such that the patient only has 4 cycles per year. Unfortunately, this regimen has greater risk of spotting and breakthrough bleeding than those using monthly cycles. Progestins
Progestins (e.g., 10 mg medroxyprogesterone, 200 mg micronized progesterone) can be administered daily from day 15 to 26 of each cycle to regulate menses in anovulatory patients. This safe and effective approach has none of the side effects or risks associated with oral estrogens and can be used in women of all ages. Progestins given in this manner also prevent endometrial hyperplasia and cancer. In some women, progestins also result in “premenstrual” symptoms, including mood changes or depression, nausea, breast tenderness, and bloating. In menorrhagia (ovulatory AUB) luteal phase progestins have been shown to be less effective than other medications, including NSAIDs. Longer courses such as 21 days of therapy may be required.51 Luteal phase progestin therapy is less effective than tranexamic acid, danazol, or the progesterone-releasing intrauterine system (IUS). Progestin therapy for 21 days of the cycle (e.g., day 5 to day 26) is more effective.
approximately 2 weeks by pituitary down-regulation, hypoestrogenemia, and complete cessation of menses. GnRH antagonists avoid this flare, but have only recently become available and their clinical utility remains to be determined. All GnRH analogues are associated with symptoms of acute estrogen deprivation, most notably hot flashes, and bone loss that is to some degree irreversible after 6 months of use. For these reasons and because of expense, the GnRH analogues are rarely used for long-term treatment of AUB. Levonorgestrel-Containing Intrauterine System
The levonorgestrel-containing IUS, developed originally for contraception, is effective for the treatment of both menorrhagia and dysmenorrhea (see Chapter 27). The local release of levonorgestrel into the uterine cavity suppresses endometrial growth and has been shown to decrease menstrual blood loss by as much as 97%.53 Although many women complain of intermenstrual bleeding during the first few months of use, as many as 20% will have amenorrhea after a year. Even though the progestins are administered locally, some women complain of systemic side effects, such as breast tenderness. Although the initial cost of the levonorgestrel-containing IUS is high compared to other medical treatment, these devices are now approved for 10 years of uninterrupted use and are thus very cost-effective for longterm therapy. Danazol
This synthetic derivative of testosterone has been shown to be effective for menorrhagia in doses between 200 and 400 mg. However, the androgenic side effects, need for barrier contraception, and the need to take the medication daily for long periods of time limit its use. Desmopressin
This drug is useful in decreasing bleeding in women with von Willebrand’s disease. It increases factor VIII and vWF. It has several potential routes of administration, such as intravenous, subcutaneous, and intranasal. Its main side effects are vasomotor; potential hyponatremia is associated with its use. Hormone Replacement Therapy
Some women older than age 40 with ovulatory dysfunction will also complain of symptoms of reduced estrogen production, such as hot flashes or sleep disturbances. Many of these women treated with continuous estrogen and cyclic progestin therapy will obtain symptomatic relief; up to 90% will respond with predictable progesterone withdrawal bleeding.54 The potential increased risk of venous thrombosis, cardiovascular disease, and breast cancer should be discussed with the patient.
Nonsteroidal Anti-inflammatory Drugs
NSAIDs have long been used to reduce dysmenorrhea as well as the amount of menstrual flow, at least in part by inhibiting prostaglandin synthesis.52 Although studies are limited, NSAIDs appear to be an effective way to treat AUB in ovulatory women (menorrhagia). NSAIDs should not be used for women with von Willebrand’s disease or a platelet dysfunction. GnRH Analogues
Continuous administration of a GnRH antagonist results in increased ovarian stimulation (referred to as a flare) followed in
Surgical Treatment for Abnormal Uterine Bleeding without Uterine Pathology If medical management of AUB is unsuccessful and the woman is not interested in childbearing, surgical therapies, including endometrial ablation and hysterectomy, are often utilized. Endometrial ablation is the least invasive surgical procedure available and has been shown to result in less morbidity and shorter recovery periods and be more cost-effective than hysterectomy in the short term (see Chapter 42). Because women who undergo
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Section 3 Adult Reproductive Endocrinology endometrial ablation can have residual active endometrium, they should receive progestin if they are prescribed estrogen hormone replacement therapy after menopause. Hysterectomy remains a reasonable option for some women with AUB who fail medical management. As many as 20% of women who undergo endometrial ablation will subsequently undergo hysterectomy within 5 years, and some studies demonstrated a higher satisfaction rate in women who initially underwent hysterectomy rather than endometrial ablation.55,56
PEARLS ●
● ●
●
CONCLUSION AUB remains one of the most challenging gynecologic problems. Every gynecologist must have comprehensive knowledge of the most common causes of this problem. Appropriate diagnostic workup begins with a careful history, followed by indicated laboratory and imaging tests. Medical treatment improves symptoms for the majority of women with AUB. Surgical evaluation and treatment for AUB remain important aspects of gynecologic care.
●
●
●
● ●
Investigation of abnormal uterine bleeding should include an initial evaluation to rule out pregnancy and cervical pathology followed by anatomic assessment of the uterus and uterine cavity by ultrasound and possible sonohysterogram or biopsy. Irregular (nonovulatory) cycles are often due to PCOS. A patient with completely normal results on investigation with ovulatory cycles should be investigated for von Willebrand’s disease. The treatment of choice is NSAIDs or oral contraceptives. Patients with anovulatory bleeding may respond to cyclic progestins. Ovulatory AUB may require a longer course of therapy. The norgestrel-containing intrauterine system is an effective option if the more conservative treatment options fail. Desmopressin is very effective for patients with von Willebrand’s disease. Intravenous estrogens are effective for acute bleeding. D&C may be effective for an acute bleed but has no long-term benefit.
REFERENCES
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1. Coulter A, Bradlow J, Agass M, et al: Outcomes of referrals to gynaecology outpatient clinics for menstrual problems: An audit of general practice records. BJOG 98:789–796, 1991. 2. Carlson KJ, Nichols DH, Schiff I: Indications for hysterectomy. NEJM 328:856–860, 1993. 3. Fraser IS: Menorrhagia—a pragmatic approach to the understanding of causes and the need for investigations. BJOG 101(Suppl 11):3–7, 1994. 4. Bayer SR, DeCherney AH: Clinical manifestations and treatment of dysfunctional uterine bleeding. JAMA 269:1823–1828, 1993. 5. Fraser IS, Critchley HOD, Munro MG, Broder M: A process designed to lead to international agreement on terminologies and definitions used to describe abnormalities of menstrual bleeding. Fertil Steril 2007. 6. Falco P, Zagonari S, Gabrielli S, et al: Sonography of pregnancies with first-trimester bleeding and a small intrauterine gestational sac without a demonstrable embryo. Ultrasound Obstet Gynecol 21:62–65, 2003. 7. Barnhart K, Esposito M, Coutifaris C: An update on the medical treatment of ectopic pregnancy. Obstet Gynecol Clin North Am 27:653–667, 2000. 8. Soto-Wright V, Bernstein M, Goldstein DP, Berkowitz RS: The changing clinical presentation of complete molar pregnancy. Obstet Gynecol 86:775–779, 1995. 9. Eschenbach DA: Acute pelvic inflammatory disease: Etiology, risk factors and pathogenesis. Clin Obstet Gynecol 19:147–169, 1976. 10. Heatley MK: The association between clinical and pathological features in histologically identified chronic endometritis. J Obstet Gynaecol 24:801–803, 2004. 11. Eckert LO, Thwin SS, Hillier SL, et al: The antimicrobial treatment of subacute endometritis: A proof of concept study. Am J Obstet Gynecol 190:305–313, 2004. 12. Marrazzo JM, Handsfield HH, Whittington WL: Predicting chlamydial and gonococcal cervical infection: Implications for management of cervicitis. Obstet Gynecol 100:579–584, 2002. 13. Gotz HM, van Bergen JE, Veldhuijzen IK, et al: A prediction rule for selective screening of Chlamydia trachomatis infection. Sex Transm Infect 81:24–30, 2005. 14. Jones H: Clinical pathway for evaluating women with abnormal uterine bleeding. Obstet Gynecol Surv 57:22–24, 2002. 15. Day Baird D, Dunson DB, Hill MC, et al: High cumulative incidence of uterine leiomyoma in black and white women: Ultrasound evidence. Am J Obstet Gynecol 188:100–107, 2003.
16. Hileeto D, Fadare O, Martel M, Zheng W: Age dependent association of endometrial polyps with increased risk of cancer involvement. World J Surg Oncol 3:8, 2005. 17. Breitkopf DM, Frederickson RA, Snyder RR: Detection of benign endometrial masses by endometrial stripe measurement in premenopausal women. Obstet Gynecol 104:120–125, 2004. 18. Clevenger-Hoeft M, Syrop CH, Stovall DW, Van Voorhis BJ: Sonohysterography in premenopausal women with and without abnormal bleeding. Obstet Gynecol 94:516, 1999. 19. ACOG Committee Opinion: Von Willebrand’s disease in gynecologic practice. Obstet Gynecol 98:1185–1186, 2001. 20. Young RH, Clement PB: Pseudoneoplastic glandular lesions of the uterine cervix. Semin Diagn Pathol 8:234–249, 1991. 21. Rosenthal AN, Panoskaltsis T, Smith T, Soutter WP: The frequency of significant pathology in women attending a general gynaecological service for postcoital bleeding. BJOG 108:103–106, 2001. 22. Matalliotakis IM, Kourtis AI, Panidis DK: Adenomyosis. Obstet Gynecol Clin North Am 30:63–82, 2003. 23. Bazot M, Cortez A, Darai E, et al: Ultrasonography compared with magnetic resonance imaging for the diagnosis of adenomyosis: Correlation with histopathology. Hum Reprod 16:2427–2433, 2001. 24. Krettek JE, Arkin SI, Chaisilwattana P, Monif GR: Chlamydia trachomatis in patients who used oral contraceptives and had intermenstrual spotting. Obstet Gynecol 81:728–731, 1993. 25. Lethaby A, Suckling J, Barlow D, et al: Hormone replacement therapy in postmenopausal women: Endometrial hyperplasia and irregular bleeding. Cochrane Database Syst Rev 3:CD000402, 2004. 26. Barakat RR, Gilewski TA, Almadrones L, et al: Effect of adjuvant tamoxifen on the endometrium of women with breast cancer. J Clin Oncol 18:3459–3463, 2000. 27. Tsalikis T, Zepiridis L, Zafrakas M, et al: Endometrial lesions causing uterine bleeding in postmenopausal women receiving raloxifene. Maturitas 51:215–218, 2005. 28. Zhang J, Salamonsen LA: In vivo evidence for active matrix metalloproteinases in human endometrium supports their role in tissue breakdown at menstruation. J Clin Endocrinol Metab 87:2346–2351, 2002. 29. Brenner PF: Differential diagnosis of abnormal uterine bleeding. Am J Obstet Gynecol 175:766–769, 1996. 30. Tsilchorozidou T, Overton C, Conway GS: The pathophysiology of polycystic ovary syndrome. Clin Endocrinol (Oxf) 60:1–17, 2004.
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Chapter 21 Abnormal Uterine Bleeding 31. Zawadski JK, Dunaif A: Diagnostic criteria for polycystic ovary syndrome: Towards a rational approach. In Dunaif A, Givens JR, Haseltine FP, Merriam GE. Polycystic Ovary Syndrome. Boston, Blackwell Scientific, 1992, pp 377–384. 32. Lakhani K, Prelevic G, Seifalian A, et al: Polycystic ovary syndrome, diabetes and cardiovascular disease: Risks and risk factors. J Obstet Gynaecol 24:613–621, 2004. 33. Pugeat M, Ducluzeau PH: Insulin resistance, polycystic ovary syndrome and metformin. Drugs 58(Suppl 1):41–46, 1999. 34. Chang RJ: A practical approach to the diagnosis of polycystic ovary syndrome. Am J Obstet Gynecol 191:713–717, 2004. 35. Holley JL: The hypothalamic-pituitary axis in men and women with chronic kidney disease. Adv Chronic Kidney Dis 11:337–341, 2004. 36. Falcone T, Desjardins C, Bourque J, et al: Dysfunctional uterine bleeding in adolescents. J Reprod Med 39:761–764, 1994. 37. Bravender T, Emans SJ: Menstrual disorders: Dysfunctional uterine bleeding. Pediatr Clin North Am 46:545–553, 1999. 38. Minakuchi K, Hirai K, Kawamura N, et al: Case of hemorrhagic shock due to hypermenorrhea during anticoagulant therapy. Arch Gynecol Obstet 264:99–100, 2000. 39. Woo YL, White B, Corbally R, et al: Von Willebrand’s disease: An important cause of dysfunctional uterine bleeding. Blood Coagul Fibrinolysis 13:89–93, 2002. 40. Kouides PA: Menorrhagia from a haematologist’s point of view. Part I: Initial evaluation. Haemophilia 8:330–338, 2002. 41. Sahin Y, Kelestimur F: The frequency of late-onset 21-hydroxylase and 11 β-hydroxylase deficiency in women with polycystic ovary syndrome. Eur J Endocrinol 137:670–674, 1997. 42. Kouides PA: Evaluation of abnormal bleeding in women. Curr Hematol Rep 1:11–18, 2002. 43. ACOG Practice Bulletin: Management of anovulatory bleeding. Int J Gynaecol Obstet 72:263–271, 2001.
44. Zreik TG, Odunsi K, Cass I, et al: A case of fatal pulmonary thromboembolism associated with the use of intravenous estrogen therapy. Fertil Steril 71:373–375, 1999. 45. Ferenczy A: Pathophysiology of endometrial bleeding. Maturitas 45:1–14, 2003. 46. Larsson PG, Bergman B, Forsum U, Pahlson C: Treatment of bacterial vaginosis in women with vaginal bleeding complications or discharge and harboring Mobiluncus. Gynecol Obstet Invest 29:296–300,1990. 47. Moller BR, Kristiansen FV, Thorsen P, et al: Sterility of the uterine cavity. Acta Obstet Gynecol Scand 74:216–219, 1995. 48. Krettek JE, Arkin SI, Chaisilwattana P, Monif GR: Chlamydia trachomatis in patients who used oral contraceptives and had intermenstrual spotting. Obstet Gynecol 81:728–731, 1993. 49. Sulak PJ: The career woman and oral contraceptive use. Int J Fertil 36(Suppl 2):90–97, 1991. 50. Sulak PJ, Cressman BE, Waldrop E, et al. Extending the duration of active oral contraceptive pills to manage hormone withdrawal symptoms. Obstet Gynecol 89:179–183, 1997. 51. Lethaby A, Irbine G, Cameron I: Cyclical progestogens for heavy menstrual bleeding. Cochrane Database Syst Rev 3, 2005, CD001016. 52. Higham JM: The medical management of menorrhagia. Br J Hosp Med 45:19–21, 1991. 53. Hurskainen R, Teperi J, Rissanen P, et al: Clinical outcomes and costs with the levonorgestrel-releasing intrauterine system or hysterectomy for treatment of menorrhagia: Randomized trial 5 year follow up. JAMA 291:1456–1463, 2004. 54. Strickland DM, Hammond TL: Postmenopausal estrogen replacement in a large gynecologic practice. Am J Gynecol Health 2:26–31, 1988 55. Comino R, Torrejon R: Hysterectomy after endometrial ablationresection. J Am Assoc Gynecol Laparosc 11:495–499, 2004. 56. Lethaby A, Shepperd S, Cooke I, Farquhar C: Endometrial resection and ablation versus hysterectomy for heavy menstrual bleeding. Cochrane Database Syst Rev. 2000;CD000329.
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Section 3 Adult Reproductive Endocrinology Chapter
22
Management of Pituitary, Adrenal, and Thyroid Disease S. Sethu K. Reddy and Maria Fleseriu
INTRODUCTION The reproductive system is often affected by disorders of other endocrine glands, such as the pituitary, thyroid, and adrenal glands. Classic endocrine disorders bear the name of distinguished physicians such as Harvey Cushing, who in 1932 described a syndrome that included disruption of the menstrual cycle, truncal obesity, hypertension, and hirsutism. Obstetricians and gynecologists require an understanding of the physiologic adjustments of different endocrine glands in pregnancy to assess potential endocrine disorders. This chapter gives the general principles of clinical presentation, investigation, and management of the most common endocrine disorders associated with reproductive dysfunction.
PITUITARY DISORDERS Anatomy The pituitary gland weighs from 500 to 1000 mg and sits in the sella turcica immediately behind the sphenoid sinus. It has anterior and posterior bony walls and a bony floor. Above is a layer of dura (diaphragma sella) and then the optic chiasma, hypothalamus, and third ventricle. Laterally on each side is the cavernous sinus, inclusive of the internal carotid artery and cranial nerves III, IV, V1, V2, and VI. The optic chiasma may be in front of (15%), above (80%), or behind the sella (5%). Within this optic chiasma, nerve fibers from the nasal half of the retina cross over to the opposite optic tract while those from the temporal half remain uncrossed. The close association of the pituitary gland with the optic chiasma explains the visual symptoms associated with expanding masses in this region.1 The median eminence is an intensely vascular component at the baseline of the hypothalamus that forms the floor of the third ventricle. The pituitary stalk arises from the median eminence. The hypothalamus extends anteriorly to the optic chiasma and posteriorly to the mammillary bodies. It was not until the mid-1960s that hypothalamic releasing hormones were isolated and identified (Table 22-1).
Physiology Thyrotropin-releasing hormone (TRH) was the first releasing hormone to be identified. In subsequent years, other releasing hormones were identified. Of note, prolactin is under tonic inhibitory influence, with dopamine acting as a prolactin releaseinhibiting factor. Magnetic resonance imaging (MRI) is the best
method for visualization of hypothalamic–pitutiary anatomy, because the optic chiasma, vascular structures, and tumor extension to the cavernous sinuses can be well visualized on MRI compared to other imaging techniques.
Pituitary Tumors Pituitary tumors may present with either hypofunction or hyperfunction, as well as symptoms directly related to the mass effect of the tumor (Table 22-2). Since the advent of computed tomography (CT), microadenomas have been arbitrarily designated as equal to or less than 10 mm in diameter and macroadenomas as greater than 10 mm in diameter. They are invariably benign, with no sex predilection. Pituitary adenomas are rarely associated with parathyroid and pancreatic hyperplasia or neoplasia as part of the multiple endocrine neoplasia type I (MEN I) syndrome. Pituitary carcinomas are rare, but metastases from other solid malignancies can occur more frequently.2
PITUITARY ADENOMAS Approximately 50% of pituitary adenomas are prolactinomas, 15% are growth hormone (GH)-producing, 10% are corticotropinproducing, and less than 1% secrete thyrotropin. Nonfunctioning pituitary adenomas, or more appropriately named nonsecretory adenomas represent about 25% of pituitary tumors. Most of
Table 22-1 Pituitary Hormones, Hypothalamic Hormones, and Other Regulatory Factors Pituitary Hormones
Hypothalamic Hormones
Other Regulatory Factors
Thyrotropin
TRH
T4, T3, dopamine, Pit-1
Corticotropin
CRH
ADH, adrenaline, cortisol
Luteinizing hormone
LH-RH
Estrogen, progesterone, testosterone
Follicle-stimulating hormone
LH-RH
Activin, estrogen, inhibin, follistatin, testosterone
Growth hormone
GH-RH
Somatostatin, estrogens, T4, Pit-1
Prolactin
PRF
Dopamine, TRH, Pit-1, estrogen, serotonin, vasoactive intestinal peptide, GnRH-associated peptide
TRH, thyrotropin-releasing hormone; CRH, corticotropin-releasing hormone; LH-RH, luteinizing hormone-releasing hormone; GH-RH, growth hormone-releasing hormone; PRF, prolactin-releasing factor; Pit-1, pituitary-specific transcription factor; ADH, antidiuretic hormone.
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Section 3 Adult Reproductive Endocrinology Table 22-2 Clinical Manifestations of Pituitary Tumors Endocrine Effects Mass Effects
Hyperpituitarism
Hypopituitarism
Headaches
GH: acromegaly
GH: short stature in children, increased fat mass, decreased strength and well-being in adults
Chiasmal syndrome
Prolactin: hyperprolactinemia
Prolactin: failure of postpartum lactation
Hypothalamic syndrome
Corticotropin: Cushing’s disease Nelson’s syndrome
Corticotropin: hypocortisolism
Disturbances of thirst, appetite, satiety, sleep, and temperature regulation
LH/FSH: gonadal dysfunction or silent α-subunit secretion
LH or FSH: hypogonadism
Diabetes insipidus
Thyrotropin hyperthyroidism
Thyrotropin: hypothyroidism
SIADH Obstructive hydrocephalus Cranial nerves III, IV, V1, V2, and VI dysfunction Temporal lobe dysfunction Nasopharyngeal mass CSF rhinorrhea SIADH = syndrome of inappropriate antidiuretic hormone; GH = growth hormone; LH = luteinizing hormone; FSH = follicle-stimulating hormone.
these adenomas on morphologic examination reveal granules containing hormones, typically components of glycoprotein hormones. Autopsy studies suggest that up to 20% of normal individuals harbor incidental pituitary microadenomas that are pathologically similar in distribution to those that present clinically.3 Impingement on the optic chiasma or its branches by pituitary pathology may result in visual field defects, with the most common being bitemporal hemianopsia. Lateral extension of the pituitary mass to the cavernous sinuses may result in diplopia, ptosis, or altered facial sensation. Among the cranial nerves, palsy of CN III is the most common. Premenopausal women often present with smaller pituitary tumors because they seek medical attention once altered menses are noted. The initial workup for most suspected adenomas should be limited and should include a serum prolactin and insulin-like growth factor-I (IGF-I) level. Other screening tests may be performed depending on clinical features.
Prolactinoma Prolactin Physiology
The pituitary content of prolactin is approximately 100 μg but can increase 10- to 20-fold during pregnancy and lactation. Although breast tissue is the most important target organ for prolactin, prolactin receptors have been identified in various tissues, including the liver, kidney, ovaries, testes, prostate, and seminal vesicles. Dopamine is the major inhibitor of prolactin secretion, and any mechanisms that interrupt dopamine transport from the hypothalamus or reduce dopamine activity in the pituitary can lead to elevated levels of serum prolactin. Estrogens, TRH, and serotonin increase prolactin levels. Whereas H2 receptors inhibit prolactin secretion, H1 receptors stimulate its secretion. Hyperprolactinemia
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Hyperprolactinemia is the most common pituitary disorder. Estrogen therapy in the past was suggested as a cause of
prolactinoma formation, but careful case-cohort studies have found no evidence that oral contraceptives induce development of prolactinomas. Clonal analysis of tumor DNA indicates that prolactinomas are monoclonal in origin. Hyperprolactinemia impairs pulsatile gonadotropin (luteinizing hormone [LH] and follicle-stimulating hormone [FSH]) release, likely through alteration in hypothalamic luteinizing hormonereleasing hormone (LHRH) secretion. Women of reproductive age usually present with oligomenorrhea, amenorrhea, galactorrhea, and infertility. Those with longstanding amenorrhea are less likely to have galactorrhea secondary to longstanding estrogen deficiency. Postmenopausal women and men usually come to medical attention because of a mass effect, such as headaches and visual field defects.4 Many men with hyperprolactinemia do not report any sexual dysfunction, but once treated effectively for hyperprolactinemia, the majority realize the presence of problems, including decreased libido and erectile dysfunction. Men with longstanding hypogonadism may have decreased beard and body hair, with soft but usually normal-size testes. If hypogonadism starts before completion of puberty, testes will be small. Patients with microadenomas have higher frequency of headaches compared to control subjects. Drug history is an important part of the initial evaluation of patients with elevated prolactin level, because some medications are associated with hyperprolactinemia and their discontinuation (if possible) will avoid any further, often expensive, workup. Other common conditions associated with elevated prolactin levels include pregnancy and hypothyroidism (Table 22-3). The prolactin level usually correlates well with the size of the tumor. Serum prolactin level above 200 μg/L is almost always indicative of a prolactin-producing pituitary tumor. However, a serum prolactin level below 200 μg/L can be seen in the presence of a large pituitary adenoma, because stalk compression from an adenoma that does not secrete prolactin can also cause hyperprolactinemia. Stimulatory tests, including the TRH stimulation test, which are performed to determine whether an
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Chapter 22 Management of Pituitary, Adrenal, and Thyroid Disease Table 22-4 Clinical Signs and Symptoms of Acromegaly
Table 22-3 Differential Diagnosis of Hyperprolactinemia Physiologic
Pathologic
Pharmacologic
Coarsening of facial features
Pregnancy
Prolactinoma
TRH
Prominent jaw and frontal sinus
Postpartum
Acromegaly (25%)
Psychotropic medications
Broadening of hands and feet
Newborn
Hypothalamic disorders
Phenothiazines
Hyperhidrosis
Stress
“Chiari-Frommel”
Reserpine
Macroglossia
Hypoglycemia
Craniopharyngioma
Methyldopa
Signs of hypopituitarism
Sleep
Metastatic disease
Estrogen therapy
Diabetes mellitus (10%–25%)
Postprandial hypoglycemia
Pituitary stalk secretion or compression
Metoclopramide, cimetidine (especially intravenous)
Skin tags (screening for colonic polyps required)
Intercourse
Hypothyroidism
Opiates
Cardiomyopathy (50%–80%)
Nipple stimulation
Renal failure
Verapamil
Carpal tunnel syndrome
Liver disease
Some SSRIs, including fluoxetine and fluvoxamine
Sleep apnea (5%)
Chest wall trauma (burns, shingles) SSRI = Selective serotonin reuptake inhibitor.
elevated prolactin is a result of a prolactinoma, are nonspecific and cannot be used to diagnose or exclude a tumor. Large prolactinomas may be associated with a falsely low prolactin level. Dilution of serum will reveal the markedly elevated prolactin levels. Observational studies in patients with microadenomas indicate that serum prolactin concentration or adenoma size increases in only a minority of patients; indeed, serum prolactin deceases in a majority of patients over time. Details of the relationship between prolactin adenomas and amenorrhea are found in Chapter 16. Treatment
Dopamine agonists are now the first-line treatment for prolactinoma, because surgical resection is curative only in a minority of patients and is associated with a high risk of side effects and recurrence in all patients. Bromocriptine mesylate (Parlodel), pergolide mesylate (Permax), and cabergoline (Dostinex) are potent inhibitors of prolactin secretion, and their use often results in tumor shrinkage. Suppression of prolactin secretion by dopamine agonists depends on the number and affinity of dopamine receptors on lactotrope adenoma. There is usually a substantial decrease in prolactin level even when serum prolactin levels do not normalize. These medications should be initiated slowly, because side effects often occur at the beginning of treatment. The most common side effects of dopamine agonists include nausea, headache, dizziness, nasal congestion, and constipation. In men treated for prolactinomas, it may take up to 6 months before testosterone increases and normal sexual function is restored. Prolactin appears to have an independent effect on libido in men, because exogenous testosterone works poorly in restoring libido in those who continue to have elevated prolactin levels. Although patients with microadenomas or those without evidence of a pituitary tumor can sometimes be followed without therapy, patients with macroadenomas always need to be treated. Occasionally a patient with microadenoma or no definite pituitary
Hypertension (25%–30%)
tumor has no increase in prolactin concentration once the dopamine agonist is discontinued. For this reason, it would be reasonable to try a “drug holiday” after several years of therapy with close follow-up. Medical therapy during pregnancy often stirs debate about the continuation of bromocriptine. Tumor-related complications are seen in about 15% of pregnancies and in only 5% of women with microadenomas. A sensible approach would be to stop bromocriptine when pregnancy begins, and then follow the clinical status with serum prolactin levels and visual field examinations. If there is significant worsening in clinical status, bromocriptine could be reinstituted. The adenoma can be followed yearly by MRI, increasing the duration between imaging studies if size is stable.5 Transsphenoidal surgery is reserved for patients with disease refractory to medical therapy. Even in patients with a mass effect, including visual field defects, dopamine agonists are the first line of therapy, because a rapid improvement in symptoms is observed in the majority of patients. The main advantage of surgery is avoidance of chronic medical therapy. Radiation therapy may be considered for patients who poorly tolerate dopamine agonists and who will likely not be cured by surgery (e.g., tumor invasion of cavernous sinuses).
Acromegaly Acromegaly may occur at a rate of 3 to 4 cases per million per year, with mean age at diagnosis of 40 years in men and 45 years in women. The GH-secreting tumors tend to be more aggressive in younger patients. Classical clinical features are listed in Table 22-4. More than 95% of cases of acromegaly are caused by GH-secreting pituitary tumors. In rare cases, they are caused by ectopic GH-releasing hormone (GH-RH) secretion, mainly carcinoids and pancreatic islet cell tumors. Patients with acromegaly have a 3.5-fold increased mortality rate, with cardiovascular disease being the most common cause of death. Somatotrope adenomas appear to be monoclonal in origin. A gsp mutation in a GspIa subunit in GH cells, leading to continuous GH secretion, has been shown to cause acromegaly.6 Due to the pulsatile nature of GH secretion, random GH levels can overlap in acromegalic patients and controls. Therefore, a single GH level is usually inadequate to establish the diagnosis.
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Section 3 Adult Reproductive Endocrinology Insulin-like growth factor-I has a longer plasma half-life than GH and is an excellent initial screening test for those suspected to have acromegaly. An elevated IGF-I level in a clinical setting suggestive of acromegaly almost always confirms the diagnosis. Patients with poorly controlled diabetes and malnutrition may have falsely low serum IGF-I levels. The oral glucose tolerance test remains the gold standard test to confirm the diagnosis. Normal individuals suppress their GH level to less than 1 μg/L (using chemiluminescent assays) within 2 hours after ingestion of 100 grams of oral glucose solution. With respect to women’s health, one should note that GH-secreting tumors may also cosecrete prolactin; thus, women may present with symptoms of hyperprolactinemia and only subtle symptoms of acromegaly. This cosecretion may occur over several years. The patient may initially present with high prolactin levels and several years later may start secreting excess GH. Particular attention to early detection of cardiovascular disease should be made, because it is the primary cause of mortality in these patients. Patients with acromegaly have increased risk of colon polyps with potential for increased risk of malignancy, affecting their life expectancy. For this reason they should undergo colonoscopy every 3 to 5 years until more outcome data are available. It is not clear if more rigorous screening for a variety of cancers, including breast, lung, or prostate cancer, is indicated. Treatment
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The primary aims of treatment include relief of the symptoms, reduction of tumor bulk, normalization of IGF-I and GH dynamics, and prevention of tumor regrowth. Medical treatment of acromegaly has gained significance since the limitations of radiation and surgical therapy have become evident. Somatostatin analogues are the most effective medical therapy available for acromegaly. Octreotide therapy has significantly changed the management of acromegaly with lowering and normalization of IGF-I in 90% and 65% of patients, respectively. Octreotide is usually given as a subcutaneous injection three times per day. The long-acting octreotide (Sandostatin LAR) has been approved by the U.S. Food and Drug Administration (FDA) for medical therapy of acromegaly as a monthly intramuscular injection. Long-term observations of patients on somatostatin analogues have shown no evidence for tachyphylaxis. Some degree of tumor shrinkage is expected in up to 50% of patients, although in most cases there is less than 50% shrinkage in tumor size. The most common side effects are gastrointestinal, including diarrhea, abdominal pain, and nausea. The most serious side effect of somatostatin analogues is cholelithiasis, seen in up to 25% of patients. Its long-term management is similar to that for cholelithiasis in the general population, and routine ultrasonographic screening is not indicated. There have been very few reports of the use of a somatostatin analogue during pregnancy.7,8 Normalization of IGF-I is seen in only 10% to 15% of patients treated with dopamine agonists and is more likely with pituitary tumors secreting both GH and prolactin. Surgical approach is the treatment of choice in those presenting with pituitary microadenoma or when tumor is confined to the sella, with cure rates up to 90%. However, patients with acromegaly who have a macroadenoma will have a surgical cure less than 50% of the
time. Even in those not cured by surgery, tumor debulking usually results in improvement of symptoms and lowering of IGF-I levels. Radiation therapy almost always induces a decrease in size of the tumor and GH level but often fails to normalize IGF-I levels. In view of its low efficacy, high risk of hypopituitarism, and the lack of knowledge about its long-term effect on neuropsychiatric functions, radiation therapy should be reserved for those not responsive to other treatment modalities. Radiosurgery (gamma knife) seems to be superior to conventional radiation therapy, but large studies on efficacy and long-term safety profile are lacking. The most important recent development in the treatment of acromegaly is the introduction of a novel GH receptor antagonist. This is a recombinant modified GH molecule conjugated with polyethyleneglycol (PEG), which prevents the GH receptor from dimerization. In clinical practice, although pituitary-derived GH levels increase by a third, serum IGF-I levels are normalized in more than 90% of patients. This drug (Pegvisomant) is currently administered as a daily subcutaneous injection of approximately 1 mL. Theoretical concerns exist for pituitary tumor growth but have not been substantiated.
Cushing’s Disease Corticotropin-secreting pituitary adenoma is the most common cause of endogenous Cushing’s syndrome (60%), with the rest being adrenal (25%) or ectopic (15%) in origin. The term Cushing’s disease refers specifically to a pituitary tumor as the cause. Signs and symptoms suggestive of hypercortisolism are listed in Table 22-5. Many signs and symptoms of Cushing’s disease are nonspecific, including hypertension, abnormal glucose tolerance, menstrual irregularities, and psychiatric disturbances, including depression. Most women with Cushing’s disease have reduced fertility.9 Women with Cushing’s disease typically have fine facial lanugo hair and may have acne and temporal scalp hair loss secondary
Table 22-5 Signs and Symptoms of Cushing’s Syndrome Clinical Feature
Approximate Prevalence (%)
Obesity General
80–95
Truncal
45–80
Hypertension
75–90
Menstrual disorders
75–95
Osteopenia
75–85
Facial plethora
70–90
Hirsutism
70–80
Impotence/decreased libido
65–95
Neuropsychiatric symptoms
60–95
Striae
50–70
Glucose intolerance
40–90
Weakness
30–90
Bruising
30–70
Kidney stones
15–20
Headache
10–50
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Chapter 22 Management of Pituitary, Adrenal, and Thyroid Disease Suspect Cushing Syndrome Obtain 24 hr UFC and/or 1 mg ON DST
UFC > 150% ULN/ AM cortisol > 5 μg/dl CHECK AM ACTH
UFC Normal AM cortisol < 1.8 μg/dl
Supressed ACTH
Normal or Elevated ACTH
Abd. CT Scan
8 mg ON DST CRH stim. test
an undetectable or low corticotropin level is consistent with adrenal etiology, low-normal corticotropin may be seen in both ectopic Cushing’s syndrome and corticotropin-secreting pituitary tumor. The CRH stimulation test is used to differentiate between the two. Although corticotropin levels tend to be higher in those with ectopic Cushing’s syndrome compared to patients with pituitary disease, there is considerable overlap. The high-dose dexamethasone test or the CRH stimulation test is helpful in differentiation of the two disorders. Cortisol levels are not suppressed with the high-dose (8 mg) dexamethasone test in patients with ectopic corticotropin syndrome, and CRH stimulation may not lead to a further rise in corticotropin.10 The gold standard test to differentiate pituitary Cushing’s syndrome from ectopic corticotropin-producing tumor is inferior petrosal sinus sampling. This test should be performed by an experienced neuroradiologist; it is essential to note that it cannot be used to make the diagnosis of Cushing’s syndrome. Ectopic Corticotropin Syndrome
Normal ACTH response AM cortisol reduced >50%
Flat ACTH response
MRI Sella
CXR, Abd. CT, Lung CT
Figure 22-1 Laboratory investigation of a patient with a clinical suspicion of Cushing’s syndrome. ULN, upper limit of normal; ON DST, overnight dexamethasone suppression test; UFC, urinary free cortisol; CRH, corticotropin-releasing hormone; CXR, chest x-ray; MRI, magnetic resonance imaging; Abd. CT, abdominal computed tomography.
to increased adrenal androgen secretion. There is usually a 3- to 6-year delay in diagnosis of patients with Cushing’s disease, and it may be possible to date the onset of the disease by determining which scars are pigmented due to excess secretion of corticotropin and other melanotropins. Diagnosis
Twenty-four hour urinary free cortisol measurement is the single best test for diagnosis of Cushing’s syndrome (Fig. 22-1). Because of the significant overlap between normal individuals and those with Cushing’s syndrome, random serum cortisol has no role in the diagnosis of Cushing’s syndrome. A 1-mg overnight dexamethasone suppression test with a morning cortisol level below 1.8 μg/dL virtually rules out the disease but is associated with an up to 40% false-positive rate. A combination of low-dose dexamethasone suppression test and corticotropin-releasing hormone (CRH) stimulation test has been shown to have 100% diagnostic accuracy in a National Institutes of Health study. This test may have a significant value in establishing the diagnosis in those with pseudo-Cushing’s and elevated 24-hour urinary free cortisol. Other tests useful in establishing the diagnosis of Cushing’s disease include midnight serum and salivary cortisol (see Fig. 22-1). Once the diagnosis of Cushing’s syndrome has been established, the next step is to find out whether cortisol hypersecretion is corticotropin dependent (see Fig. 22-1). Although
The most important differential diagnosis of Cushing’s disease is ectopic production of corticotropin. Ectopic ACTH syndrome is the most frequent and best studied of the ectopic hormone syndromes. Most tumors associated with ectopic corticotropin syndrome are carcinomas and have a poor prognosis. They usually present as a rapid-onset syndrome (within 6 months) associated with profound muscle weakness, hyperpigmentation, hypertension, hypokalemia, and edema. Hyperpigmentation is thought to be due to cosecretion of β-melanocyte-stimulating hormone, one of the byproducts of corticotropin synthesis. Some benign tumors, such as carcinoids or islet cell tumors, have been shown to cause ectopic corticotropin syndrome and are difficult to differentiate from pituitary causes of Cushing’s syndrome. This difficulty is increased by radiologic investigations of the sella that are often negative or show a microadenoma, which is seen in up to 20% of autopsy series in normal individuals. Treatment
Surgical (transsphenoidal) removal of corticotropin-secreting pituitary tumor is the treatment of choice. Availability of an experienced surgeon is crucial, with an 80% to 90% remission rate after surgery. An undetectable postoperative cortisol level with the patient not taking steroids is considered to be an excellent marker for long-term cure. A period of temporary adrenal insufficiency follows successful surgery, usually lasting 6 to 8 months, but possibly as long as 2 years. For those not cured by the surgery, other options include second operation and radiation therapy. Patients whose tumor is unresponsive to these therapies may then be offered medical or surgical adrenalectomy. Ectopic corticotropin-producing tumors should be resected if possible. Octreotide may inhibit ectopic corticotropin secretion. Mitotane (Lysodren) is perhaps the most effective adrenolytic agent. Other medications, such as aminoglutethimide (Cytadren), ketoconazole (Nizoral), or metyrapone (Metapyrone), are useful as temporizing agents only. The glucocorticoid antagonist mifepristone (RU-486) is a promising therapy that appears to have few side effects. One difficulty is that one cannot rely on cortisol measurements to follow the effect of mifepristone. This agent blocks cortisol action but may be associated with actual higher levels of circulating cortisol.
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Section 3 Adult Reproductive Endocrinology Nonsecretory and Glycoprotein-Secreting Pituitary Adenomas
except in those with pituitary infarction. Isolated deficiencies of various anterior pituitary hormones have also been described.
Nonsecretory Adenomas
Growth Hormone Deficiency
Nonsecretory or glycoprotein-secreting tumors are usually clinically silent because they are inefficient in secreting hormones and lack a clinically recognizable syndrome. They usually come to attention because of manifestations of a mass lesion, including headache and visual field defect. Patients may present with varying degrees of hypopituitarism due to the mass effect. Glycoprotein-secreting Adenomas
Rarely, pituitary adenomas can secret glycoproteins, including FSH, LH, or thyrotropin. An FSH adenoma may cause amenorrhea in a woman, or an LH adenoma may cause precocious puberty in a boy. Diagnosis is confirmed by measurement of either intact glycoprotein hormones or their α and β subunits. Levels of the α subunit tend to be inappropriately elevated, compared with those of the intact hormone itself.11 Thyrotropin-secreting Pituitary Adenomas
The clinical picture in patients with thyrotropin-secreting pituitary adenoma includes pituitary mass lesion, hyperthyroidism, and goiter. Their most important biochemical feature is elevation of thyroid hormone levels in the presence of normal or elevated thyrotropin level. For this reason, any patient presenting with endogenous hyperthyroidism and an elevated or normal thyrotropin level should be further evaluated for the presence of a thyrotropin-secreting pituitary adenoma. Elevations in serum prolactin and α subunit of thyrotropin are in favor of a thyrotropic adenoma and against thyroid hormone resistance syndrome, which can also elevate the thyrotropin level. Treatment
The transsphenoidal surgical approach is standard for this type of adenoma, especially if visual function is abnormal. Surgery is rarely curative because of the size of adenoma on presentation, and usually radiation therapy is needed as an adjunct. Octreotide may be helpful in reducing hormone secretion, but further studies are required to assess if it has any effect on tumor size. Dopamine agonists such as bromocriptine have been used in high doses, but clinical responses (i.e., changes in tumor size or visual symptoms) occur in less than 10% of patients. Long-acting gonadotropin-releasing hormone (GnRH) agonists and antagonists may reduce secretion of FSH and LH by tumors but do not reduce tumor size. In summary, the efficacy of medical therapy in patients with nonfunctional or glycoproteinsecreting pituitary adenoma is not established but is used in an attempt to reduce tumor hypersecretion and size after unsuccessful surgery.
HYPOPITUITARISM
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Pituitary adenomas are the most common cause of hypopituitarism, but other causes, including parasellar diseases, pituitary surgery, or radiation therapy, are possible. Head injury must also be considered. Pituitary hormone deficiency secondary to a mass effect usually occurs in the following order: GH, LH, FSH, thyrotropin, corticotropin, and prolactin. Prolactin deficiency is uncommon
Growth hormone deficiency is now recognized as a pathologic state in adults, and many patients with GH deficiency now receive GH replacement. GH deficiency may contribute to increased mortality in patients with hypopituitarism, with cardiovascular disease being the most common cause of mortality. The symptoms of GH deficiency in adults are subtle and include decreased muscle strength and exercise tolerance and reduced sense of well-being (e.g., diminished libido, social isolation). Patients with GH deficiency have increased body fat, particularly intra-abdominal fat, a well as decreased lean body mass compared to normal adults. Some patients have decreased bone mineral density, which may improve with GH replacement. A trial of GH replacement in adults with documented GH deficiency and symptoms or metabolic abnormalities suggestive of GH deficiency is indicated. The most common side effects of GH therapy include fluid retention, carpal tunnel syndrome, and arthralgia. These side effects are usually dose-related and improve with dose reduction.
Gonadotropin Deficiency Gonadotropin deficiency may be secondary to a pituitary defect, hypothalamic deficiency of GnRH, or a functional abnormality such as hyperprolactinemia, anorexia nervosa, and severe disease state. In women gonadotropin deficiency causes infertility and menstrual disorders, including amenorrhea. It is often associated with lack of libido and dyspareunia. In men hypogonadism is diagnosed less often, because decreased libido and impotence may be considered as a function of aging. Hypogonadism is often diagnosed retrospectively when the patient presents with a mass effect. Osteopenia is a consequence of longstanding hypogonadism and usually responds to hormone replacement therapy.
Corticotropin Deficiency The symptoms of secondary adrenal insufficiency from corticotropin deficiency are similar to primary adrenal insufficiency with one important difference. Mineralocorticoid secretion is mainly regulated by the renin and angiotensin system and is preserved in patients with pituitary disorders. For this reason the symptoms are more chronic in nature and commonly include malaise, loss of energy, and anorexia. Hyperkalemia is not a feature of secondary adrenal insufficiency. An acute illness may precipitate vascular collapse, hypoglycemia, and coma.
Thyrotropin Deficiency Thyrotropin deficiency is a relatively late finding in patients with pituitary disorders, with symptoms being similar to those seen with primary hypothyroidism, including malaise, leg cramps, lack of energy, and cold intolerance. The degree of hypothyroidism depends on the duration of thyrotropin deficiency.
Causes of Hypopituitarism Lymphocytic Hypophysitis
Lymphocytic hypophysitis is an autoimmune disease often presenting in women during or after pregnancy. The clinical
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Chapter 22 Management of Pituitary, Adrenal, and Thyroid Disease manifestations are secondary to hypopituitarism or adrenal insufficiency or are due to a pituitary mass effect. Serum prolactin is elevated in half of patients but may be decreased. Antipituitary antibodies are present in some patients, and other autoimmune endocrine disorders, including Hashimoto’s thyroiditis and Addison’s disease, have been seen by others.12 The diagnosis may be suspected on clinical grounds in a pregnant or postpartum woman. However, surgical biopsy is needed for confirmation of diagnosis. The natural history of lymphocytic hypophysitis is variable, worsening or improving spontaneously. Some patients recover fully, while others may need selective hormone replacement. For this reason, patients need to be assessed at regular intervals to determine the necessity of continued hormone replacement. Adequate hormone replacement therapy is crucial. Although lymphocytic hypophysitis is a chronic inflammatory process, probably of autoimmune etiology, anti-inflammatory corticosteroid treatment has not been systematically used so far. Thirteen patients in the literature were treated with a mean daily dose of 27.5 mg methylprednisolone equivalent for a mean time of 4.75 months. Lasting improvements, both endocrinologic and neuroradiologic, occurred in 15%. Transient improvements, primarily neurologic, occurred in 62% of cases. Relapse of symptoms occurred days to a few months after discontinuation of corticosteroid therapy. Recent experience from Germany suggests that one should be cautiously optimistic about high-dose steroid therapy. MRI findings improved in 88% of patients treated with high-dose steroids, but clinical normalization was quite variable, with none achieving complete recovery.13 Surgery for mass effect in lymphocytic hypophysitis can lead to rapid relief of neurologic symptoms, but endocrinologic improvement was seldom reported. Indications for surgery are the presence of gross chiasma compression, ineffectiveness of corticosteroid therapy, and the impossibility of establishing the diagnosis of lymphocytic hypophysitis with sufficient certainty by conservative evaluation.14 Empty Sella Syndrome
The diagnosis of empty sella syndrome has become increasingly more common, owing to the prevalent use of CT and MRI of the brain for headaches or other symptoms. Pituitary fossa enlargement is secondary to communication between the pituitary fossa and subarachnoid space, which causes remodeling and enlargement of the sella. Primary empty sella syndrome is the result of a congenital diaphragmatic defect; secondary empty sella syndrome may result from previous surgery, irradiation, or infarction of a preexisting tumor. Most patients have no pituitary dysfunction, but a wide spectrum of pituitary deficiencies have been described, especially in those with secondary empty sella syndrome. Coexisting tumors may occur. Management is usually with reassurance and hormone replacement, if necessary. Surgery is only necessary if visual field defects occur or if cerebrospinal fluid rhinorrhea is present. Pituitary Apoplexy
Pituitary apoplexy is an endocrine emergency resulting from hemorrhagic infarction of the pituitary usually associated with a preexisting pituitary tumor. A variety of predisposing conditions,
including bleeding disorders, diabetes mellitus, pituitary radiation, pneumoencephalography, mechanical ventilation, and trauma, have been described. The clinical manifestations of this syndrome are related to rapid expansion and compression of the pituitary gland and the perisellar structures leading to hypopituitarism, visual field defect, and cranial nerve palsies. Extravasation of blood or necrotic tissue into the subarachnoid space may cause clouding of consciousness, meningismus, and fever. If pituitary apoplexy is suspected, anterior pituitary insufficiency should be presumed and the patient must be treated accordingly. The glucocorticoid dose must be adequate for the degree of stress and presumptive cerebral edema. Any evidence of sudden visual field defects, oculomotor palsies, hypothalamic compression, or coma should lead to immediate surgical decompression. The recovery of a variety of pituitary hormone deficiencies after surgery has been documented; all patients should be reevaluated for possible recovery of their pituitary hormone axes. Sheehan’s Syndrome
Sheehan’s syndrome is the result of ischemic infarction of the normal pituitary gland, leading to hypopituitarism secondary to postpartum hemorrhage and hypotension.15 Patients have a history of failure to lactate postpartum, failure to resume menses, cold intolerance, or fatigue. Some women may have an acute crisis mimicking apoplexy within 30 days postpartum. There is often subclinical central diabetes insipidus.16
ADRENAL GLAND DISORDERS Anatomy and Physiology The adrenal gland consists of the medulla and the cortex. The cortex is further divided into the zona reticularis, the zona fasciculata, and the zona glomerulosa. The medulla produces norepinephrine and epinephrine. The zonae fasciculata and reticularis produce cortisol and androgens, mainly dehydroepiandrosterone sulfate (DHEAS). The zona glomerulosa produces aldosterone. As a result of the absence of 17-hydroxylase in the zonal glomerulosa, cortisol and androgens cannot be produced in that layer. The zonae reticularis and fasciculata are under the control of corticotropin released by the pituitary gland in response to hypothalamic CRH. CRH in turn is regulated by cortisol-negative feedback, stress, and a circadian rhythm. Besides increasing the synthesis of cortisol, corticotropin is trophic for the adrenal gland so that a lack of corticotropin results in atrophy of the zonae fasciculata and reticularis. Although corticotropin has some effect on aldosterone production, the zona glomerulosa is predominantly under the control of renin. Understanding the anatomy and physiology of the adrenal gland is crucial to understanding its hypofunction and hyperfunction.17
Adrenal Insufficiency Etiology
Clinical adrenal insufficiency results from hypofunction of the adrenal cortex. This may be due to destruction of the adrenal gland itself, referred to as Addison’s disease or primary adrenal insufficiency. Alternatively, it may be due to a lack of either corticotropin (i.e., secondary adrenal insufficiency) or CRH.18
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Section 3 Adult Reproductive Endocrinology Table 22-6 Other Causes of Primary Adrenal Insufficiency in Adults Infection Viral Human immunodeficiency virus (HIV) Mycobacterial Fungal Hemorrhage/infarction Anticoagulants/coagulopathy Sepsis
secondary adrenal insufficiency. Therefore, hyperkalemia and profound dehydration with orthostatic hypotension are seen in primary adrenal insufficiency only. Likewise, hyperpigmentation of the skin or mucous membranes (secondary to increased corticotropin) is seen in primary adrenal insufficiency only. The absence of hyperkalemia or hyperpigmentation does not exclude adrenal insufficiency. In addition to hyponatremia and hyperkalemia, laboratory abnormalities in adrenal insufficiency may include hypoglycemia (usually chronic), hypercalcemia, eosinophilia, and lymphocytosis.
Thrombosis
Diagnosis
Metastatic cancer: breast, lung, gastrointestinal, renal Infiltrative disorders: amyloidosis, sarcoidosis, hemochromatosis Adrenoleukodystrophy/adrenomyeloneuropathy Disorder seen in young men (X-linked)—abnormal accumulation of verylong-chain fatty acids in adrenal cortex, brain, testes, and liver Central nervous system demyelination
Table 22-7 Adrenal Insufficiency Signs and Symptoms Primary
Secondary
Cortisol deficiency Anorexia/nausea/vomiting Weight loss/fatigue Myalgia/arthralgia Hypotension Hyponatremia
Yes
Yes
Androgen deficiency Loss of axillary and pubic hair (usually women only)
Yes
Yes
Aldosterone deficiency Hyperkalemia Orthostasis
Yes
No
Corticotropin excess Hyperpigmentation
Yes
No
The most common cause of Addison’s disease in adults (80%) is autoimmune destruction of the adrenal gland. This is often seen in association with other autoimmune diseases, including Hashimoto’s thyroiditis, Graves’ disease, or type 1 diabetes mellitus. Adrenal insufficiency in this setting is known as type II autoimmune polyglandular syndrome. Type I autoimmune polyglandular syndrome, more commonly seen in children, consists of Addison’s disease, hypoparathyroidism, and mucocutaneous candidiasis. Other causes associated with adrenal insufficiency are listed in Table 22-6. Currently, acquired immunodeficiency syndrome is the most common cause of infectious adrenal destruction, and the antiphospholipid syndrome (lupus anticoagulant) is increasingly being recognized as a cause of adrenal hemorrhage. Secondary adrenal insufficiency is a result of adrenal gland atrophy from corticotropin deficiency. This most often results from pituitary corticotroph atrophy owing to previous exogenous glucocorticoid use,19 hypopituitarism, or isolated corticotropin deficiency (usually postpartum). Clinical Presentation
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The underlying etiology of adrenal insufficiency determines the clinical presentation (Table 22-7). Under the regulation of corticotropin, cortisol and adrenal androgens are lost in both primary and secondary adrenal insufficiency. Aldosterone production, predominantly regulated by renin, remains intact in
The diagnosis of adrenal insufficiency is made by demonstrating diminished responsiveness of the hypothalamic-pituitary-adrenal (HPA) axis to stimulation. A morning cortisol value less than 3 μg/dL (assuming normal cortisol-binding globulin) can be sufficient to make the diagnosis. However, the cosyntropin (Cortrosyn or corticotropin) stimulation test is usually required and is the gold standard. In this test a baseline serum cortisol is obtained and then cosyntropin 250 μg is given intramuscularly or intravenously. The serum cortisol level is drawn again after 30 to 60 minutes. A rise in the cortisol level to 18 μg/dL is a normal response. If an abnormal response is obtained, a corticotropin level then determines primary (high corticotropin) versus secondary disease (normal or low corticotropin). In secondary adrenal insufficiency, however, the corticotropin stimulation test is not always abnormal. Adequate corticotropin may be present to prevent adrenal gland atrophy, thereby resulting in a response to the supraphysiologic dose of corticotropin used in the test. However, the HPA axis may not be able to respond to stress. In patients with suspected secondary adrenal insufficiency and a normal corticotropin stimulation test, CRH is now available to assess corticotropin response. In addition, the insulin tolerance test or the metyrapone test evaluate the integrity of the HPA axis by its response to hypoglycemia or inhibited cortisol synthesis, respectively. Although not widely used, some investigators find that a 1 μg corticotropin stimulation test may be more sensitive at detecting mild adrenal insufficiency.20 Treatment
The treatment of adrenal insufficiency is replacement of the deficient hormones. The following agents may be used in treating adrenal insufficiency: ● ● ●
Hydrocortisone, 30 mg daily Prednisone, 7.5 mg daily Dexamethasone, 0.75 mg daily
Cortisol 20 mg in the morning and 10 mg in the evening, or prednisone, 5 to 7.5 mg daily, provides dramatic relief of symptoms. However, to prevent Cushing’s syndrome, the smallest dose needed to control the patient’s symptoms should be used. For a minor illness, the glucocorticoid dose should be doubled for as short a time as needed. For a major stress, parenteral hydrocortisone, 200 to 400 mg daily, is given initially and then rapidly tapered. Aldosterone replacement is required in primary adrenal insufficiency only and is given as fludrocortisone acetate (Florinef Acetate), 0.05 to 0.2 mg daily. The dose is adjusted according to the blood pressure and potassium level. Renin levels may be required to assess plasma volume. Adrenal androgens are not replaced.21
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Chapter 22 Management of Pituitary, Adrenal, and Thyroid Disease In undiagnosed patients with suspected adrenal crisis, dexamethasone, 2 to 4 mg intravenously or intramuscularly, should be given along with saline and glucose. Dexamethasone does not interfere with the cortisol assay. The corticotropin stimulation test should then be done as soon as possible. In the management of secondary adrenal insufficiency caused by previous exogenous steroids, glucocorticoids with short halflives (usually cortisone) should be given. Typically larger doses are used in the morning and smaller doses in the evening. The evening doses are gradually tapered, as symptoms permit, to allow overnight hypothalamic-pituitary “desuppression” and a rise in corticotropin level. This leads to a return of adrenal gland function. When morning cortisol reaches 10 μg/dL, replacement glucocorticoid can generally be discontinued. Stress glucocorticoids, however, should be given until result of the corticotropin stimulation test is normal. Recovery of the HPA axis from glucocorticoid suppression generally requires 6 to 12 months. Pregnancy and Adrenal Insufficiency
Because the excess estrogens in pregnancy can result in increased synthesis of cortisol binding globulin, the doses of cortisone or prednisone may need to be increased modestly. Dosing is empiric since there is no good blood test to titrate the steroid replacement. One must avoid overreplacement as well.
Hypoaldosteronism Hypoaldosteronism results from decreased aldosterone production by the zona glomerulosa of the adrenal cortex. This may be due to deficient renin stimulation or defective aldosterone production despite renin stimulation. In adults, the most common cause of primary hypoaldosteronism is adrenal insufficiency. Renal insufficiency (or type 4 renal tubular acidosis) is the most common cause of secondary hypoaldosteronism. Children and young adults may have adrenal cortex enzyme deficiencies causing hypoaldosteronism. The symptoms and signs of mineralocorticoid deficiency include hyperkalemia and metabolic acidosis. Blood pressure may be low, normal, or high. Serum sodium may be normal or low. If necessary, the diagnosis may be established by aldosterone levels that fail to rise with standing or volume depletion with diuretics. Treatment involves mineralocorticoid replacement with fludrocortisone, 0.05 to 0.2 mg daily, with dose adjustments based on blood pressure and potassium levels. Patients with hypertension or congestive heart failure are treated with loop diuretics.
Late-Onset Congenital Adrenal Hyperplasia Congenital adrenal hyperplasia (CAH), due to deficiency of an enzyme in the cortisol synthesis pathway, occurs in three variant forms: ● ● ●
Classic CAH Simple virilizing CAH Late-onset CAH.
Late-onset CAH results in relative cortisol deficiency and increased corticotropin levels. Cortisol production is normalized but at the expense of adrenal hyperplasia and increased androgens. Therefore, late-onset CAH presents with peripubertal (or later)
evidence of androgen excess (acne, hirsutism, menstrual irregularities, infertility) and adrenal hyperplasia or nodules. Adrenal insufficiency is not present. The most common (relative) enzyme deficiency is 21-hydroxylase, resulting in an accumulation of 17-hydroxyprogesterone (17-OHP). In this case, screening for late-onset CAH should be performed before the follicular phase and may include the following: ● ●
Random early-morning follicular phase 17-OHP Stimulated (by cosyntropin) 17-OHP.
Women with severe forms of CAH tend to have reduced fertility rates because of oligo-ovulation. Successful conception requires careful endocrine monitoring and often ovulation induction.22 Late-Onset CAH and Pregnancy
Fertility rates may be lower in women with CAH, but with successful medical management, women, especially those with 21-hydroxylase deficiency, may conceive.23 From a fetal and neonatal standpoint, accurate prenatal diagnosis of 21-hydroxylase deficiency and 11β-hydroxylase deficiency is necessary to allow for prenatal treatment using dexamethasone in an attempt to minimize clinical problems in the neonate. Dexamethasone can cross the placenta and suppress fetal adrenal steroidogenesis and potentially prevent masculinization of affected female fetuses.24 Large quantities of estrogen are produced during normal human pregnancy, and, after the first 3 to 4 weeks of gestation, the placenta produces nearly all of the estrogen. The major precursor for estrogen production is DHEAS, which is synthesized in the fetal adrenal gland. The adrenals of the human fetus at term are as large as those of adults, weighing 8 to 10 g or more. The fetal adrenals are principally composed of an inner fetal zone that accounts for 85% of the total volume. The outer zone, the neocortex, develops into the mature adrenal cortex, which is only 15% of the total volume. The capacity of the fetal adrenals for steroidogenesis is enormous, and near term, the fetal adrenals secrete 100 to 200 mg of the steroid per day. The total daily steroid production by the adrenals in an unstressed adult is approximately 35 mg.25 In addition to its role in providing precursors for placental estrogen formation, the fetal adrenal cortex may participate in the events that lead to the initiation of labor and maturation of the fetal lungs. Corticotropin levels in human fetal blood decline as gestation progresses, but the adrenals continue to grow in late gestation. The trophic stimulus for the fetal adrenal may not be corticotropin, and the pattern of steroids secreted by the fetal adrenal is also different. Therefore, a trophic role has been proposed for other hormones, including GH, human chorionic gonadotropin (hCG), prolactin, and human placental lactogen. More than 90% of the estradiol and estriol and 85% or more of the progesterone formed in the trophoblast are secreted into the maternal compartment. The net transfer of steroids to maternal blood is approximately 10 times that of the net transfer to fetal blood. Only a small amount of the steroids in the maternal circulation reach the fetal compartment in normal pregnancy. For example, a small amount of cortisol in maternal plasma crosses the placenta, both because the reentry pathway dominates and because cortisol within the trophoblast is converted to cortisone
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Section 3 Adult Reproductive Endocrinology by 11β -hydroxysteroid dehydrogenase. Circulating 19-carbon steroids in the maternal compartment, such as DHEAS, DHEA, androstenedione, and testosterone, do not reach the fetal compartment because of the presence of aromatase enzymes of the syncytiotrophoblast that are used for the conversion of 19-carbon steroids to estrogens. This mechanism protects the female fetus from possible virilization in women who may be hyperandrogenic during pregnancy.
Cushing’s Syndrome Pathophysiology
Cushing’s syndrome is a result of glucocorticoid excess. Endogenously, this may be due to increased corticotropin secretion by the pituitary gland (Cushing’s disease) or ectopically or to autonomous cortisol secretion by an adrenal tumor. The most common cause of Cushing’s syndrome, however, is exogenous use of glucocorticoids.
A repeat urinary free cortisol with alcohol abstention should be normal. If necessary, the low-dose dexamethasone suppression test may document true hypercortisolism. Dexamethasone 0.5 mg orally is administered every 6 hours for 48 hours, while a 24-hour urinary free cortisol including 17-hydroxysteroids (17-OHCS) is collected before and on the second day of dexamethasone. Failure to suppress 24-hour urine 17-OHCS to less than 4 mg or the urinary free cortisol to less than 25 μg suggests pathologic hypercortisolism, although pseudo-Cushing’s states occasionally cannot be suppressed. The urine 17-OHCS level is less essential because of the advent of the urinary free cortisol. Once true Cushing’s syndrome has been documented, a corticotropin level separates corticotropin-dependent from corticotropin-independent disease. The corticotropin-dependent hypercortisol diseases and syndromes are: ●
Clinical Presentation
The clinical features of Cushing’s syndrome are listed in Table 22-5. With respect to specificity for Cushing’s syndrome, thinning of the skin, purple striae, and bruising are the best clinical signs. Hypokalemia, edema, and hyperpigmentation are more commonly seen in ectopic corticotropin secretion, in which corticotropin and cortisol levels tend to be much higher. If a pregnant woman is in a hypercortisolemic state due to exogenous glucocorticoid therapy, the fetus is at potential risk of hypoadrenalism and one needs to forewarn the neonatologist. Diagnosis
The diagnosis of Cushing’s syndrome revolves around the inability to suppress the HPA axis. Two screening tests are employed: ● ●
24-hour urine collection for free cortisol and creatinine Overnight dexamethasone suppression test, in which dexamethasone 1 mg is given at 11 p.m. and a serum cortisol is drawn the following morning. A cortisol level less than 1.8 μg/dL is a normal (or negative) response.
The 24-hour urinary free cortisol and creatinine is more specific but is also more cumbersome. The value may be elevated in depression, acute illness, and alcoholism. The 1-mg overnight dexamethasone suppression test is easy to perform but falsepositive and false-negative responses are common. Causes of a false-positive test result include increased cortisolbinding globulin (high circulating estrogen), depression, acute illness, and alcoholism. Drugs that increase the metabolism of dexamethasone (rifampin, phenobarbital, and phenytoin) may also result in a false-positive response. False-negative test results may be seen in Cushing’s disease or cyclic intermittent Cushing’s syndrome. Differential Diagnosis
320
Figure 22-1 will allow confirmation of hypercortisolism and assessment of potential causes. If an abnormal result is obtained by either the 24-hour urinary free cortisol or the 1-mg overnight dexamethasone suppression test, the pseudo-Cushing’s state of alcoholism or endogenous depression should first be sought by a careful history, physical examination, and laboratory evaluation.
● ●
Cushing’s disease ectopic corticotropin production ectopic CRH production
The corticotropin-independent hypercortisol diseases and syndromes are: ● ● ● ●
adrenal adenoma adrenal carcinoma nodular adrenal hyperplasia exogenous glucocorticoids.
A low corticotropin level prompts CT of the adrenal to look for a tumor or nodules. A normal or elevated corticotropin value suggests Cushing’s disease or ectopic corticotropin production; these can be differentiated by the high-dose (8 mg) overnight dexamethasone suppression test. If a morning cortisol level suppresses by 50% in response to 8 mg of dexamethasone the evening before, the diagnosis is presumed to be Cushing’s disease. However, the specificity is not 100%. Many occult bronchial carcinoid tumors with corticotropin secretion can suppress in response to high-dose dexamethasone. Magnetic resonance imaging is not a definitive means for distinguishing pituitary from nonpituitary tumors, because 50% of Cushing’s disease patients have occult pituitary adenomas. Furthermore, up to 10% of patients may have false-positive pituitary scans (pituitary “incidentaloma”). Inferior petrosal sinus sampling (enhanced with CRH) may be necessary; an elevated sinus-to-peripheral corticotropin gradient suggests Cushing’s disease. Treatment
It should be apparent that the diagnostic workup for Cushing’s syndrome can have many pitfalls. False-positive screening tests, pseudo-Cushing’s states, modest specificity of the high-dose dexamethasone suppression test, and limitations of pituitary imaging can all lead to an erroneous diagnosis. It is important to correctly diagnose Cushing’s disease because the most appropriate treatment is transsphenoidal pituitary adenomectomy performed by an experienced neurosurgeon, although radiation therapy, ketoconazole (Nizoral), or bilateral adrenalectomy may be needed in some cases. Resection of the underlying tumor or chemotherapy is the treatment for adrenal neoplasia and ectopic corticotropin production.
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Chapter 22 Management of Pituitary, Adrenal, and Thyroid Disease Cushing’s Syndrome and Pregnancy
Although the clinical diagnosis may be difficult during pregnancy, one should seek out catabolic signs. There is also a greater likelihood of diabetes, worsening hypertension, cardiomyopathy, and psychological and muscular symptoms. The diagnostic testing, such as low- and high-dose dexamethasone testing, remains the same. One should remember that with higher cortisol binding globulin levels, the usual serum (total) cortisol levels may be falsely high.26 Poor wound healing should be anticipated as well as prolonged bleeding from any surgical procedures. Treatment is the same as for the nonpregnant state although surgical intervention such as adrenalectomy, if required, should be performed early in the second trimester. Occasionally, ketoconazole27 has been used to medically control the hypercortisolism without adverse effects on the mother or the baby. Adrenal insufficiency can occur postoperatively and therefore preventive therapy should be initiated.28
Hyperaldosteronism Excess aldosterone results in hyperaldosteronism with hypertension, hypokalemia, and metabolic alkalosis. This may be associated with Cushing’s syndrome, particularly in patients with adrenal carcinoma. Isolated primary hyperaldosteronism, marked by an elevated aldosterone level and suppressed plasma renin activity, accounts for 1% to 2% of patients with hypertension; the presence of spontaneous hypokalemia or a serum potassium level less than 3.0 mEq/L on diuretics should prompt an evaluation.29 The ratio of aldosterone (ng/dL) to plasma renin activity (ng/mL/h) is a simple screening test. However, first hypokalemia must be corrected and interfering drugs, such as diuretics, angiotensin-converting enzyme (ACE) inhibitors, and beta blockers, discontinued. A ratio greater than 20 is quite sensitive but not specific. Because the ratio can swing widely with small changes in plasma renin activity, some rely on 24-hour urinary aldosterone levels as an indicator of excess aldosterone secretion. The saline suppression test confirms the diagnosis. The test involves determination of aldosterone and plasma renin activity before and after administration of 2 L of normal saline. Normal patients suppress aldosterone to less than 5 ng/dL. A persistently elevated aldosterone-to-plasma renin activity ratio after captopril (Capoten) may also be used to confirm the diagnosis. The next step is to differentiate adrenal adenoma from hyperplasia. An adenoma can be differentiated by CT findings, increased 18-hydroxycorticosterone levels, or bilateral adrenal vein catheterization. Spironolactone (Aldactone), an aldosterone antagonist, is the treatment of choice for patients with hyperplasia, small adenomas, or contraindications to surgery.30
methasone suppresses corticotropin and subsequently excess aldosterone production. In patients with suppressed plasma renin activity and low aldosterone levels, a mineralocorticoid other than aldosterone is present. In the syndrome of apparent mineralocorticoid excess, seen in young adults, the mineralocorticoid has been identified as cortisol (which normally has little mineralocorticoid effect). Normally, cortisol is inactivated to cortisone in the renal tubular cell by 11β-hydroxysteroid dehydrogenase. Deficiency of this enzyme allows cortisol to bind to the mineralocorticoid receptor, resulting in hypertension, hypokalemia, and suppressed plasma renin activity. Natural licorice (glycyrrhizic acid) is known to inhibit 11β-hydroxysteroid dehydrogenase, thus explaining licorice-induced hypermineralocorticoidism. Excess sodium itself serves to suppress plasma renin activity and causes hypertension in Liddle’s syndrome. In this familial syndrome, constitutive activation of the kidney’s epithelial sodium channel results in increased sodium resorption and potassium excretion independently of any mineralocorticoid. Spironolactone is therefore ineffective; triamterene (Dyrenium) is the treatment of choice. Primary hyperaldosteronism is rarely observed in pregnancy.31 Plasma aldosterone levels may be normally elevated in pregnancy and urinary potassium level may be lower than that in nonpregnant patients with hyperaldosteronism due to the effects of progesterone. Plasma renin levels should be decreased in patients with primary hyperaldosteronism. In a healthy pregnancy, plasma renin activity is usually increased and decreases in the setting of primary hyperaldosteronism.32 Another dynamic test that may be used is stimulation of renin production by positioning the patient upright. In pregnant patients, prolonged standing results in a modest increase in plasma renin activity.33 If the renin activity remains suppressed, this is suggestive of primary hyperaldosteronism. Imaging studies are necessary to localize adrenal adenomas. MRI is the preferred imaging method in pregnant women. If an adrenal adenoma is detected, unilateral adrenalectomy is the treatment of choice. Cases of successful adrenalectomy in the second trimester have been reported. The goals of medical therapy should be adequate control of blood pressure and replacement of potassium. Spironolactone and ACE inhibitors are contraindicated in pregnant patients. Methyldopa, beta blockers, and calcium channel blockers can be used. Dexamethasone-suppressible hyperaldosteronism (or glucocorticoid-remediable aldosteronism) seems to be associated with a higher likelihood of exacerbation of hypertension during pregnancy.34 There does not appear to be a higher incidence of preeclampsia.
Other Mineralocorticoid Excess Syndromes
Pheochromocytoma
The pathogenesis of several mineralocorticoid excess syndromes has recently been elucidated. Dexamethasone-suppressible hyperaldosteronism is an entity that should be suspected in a young patient with elevated aldosterone levels, suppressed renin activity, and an appropriate family history of hypertension and premature strokes. Through the development of a hybrid gene, the enzyme that catalyzes the final steps of aldosterone synthesis becomes regulated by corticotropin. Treatment with dexa-
Pheochromocytoma accounts for approximately 0.1% of hypertensive patients. This tumor should be especially suspected in multiple endocrine neoplasia type II (MEN IIA and MEN IIB), in which case the disease is frequently bilateral. Clinical Presentation
The triad of headaches, palpitations, and diaphoresis in the presence of hypertension is classic for pheochromocytoma.
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Section 3 Adult Reproductive Endocrinology Table 22-8 Signs and Symptoms of Pheochromocytoma Classic symptoms Headaches, palpitations, and diaphoresis Postural hypotension Tachycardia Weight loss Pallor Hyperglycemia Anxiety Nausea/vomiting Constipation Tremulousness
Other signs and symptoms are listed in Table 22-8. More frequently recognized are silent pheochromocytomas presenting as adrenal incidentalomas. Cocaine abuse may be mistaken for pheochromocytoma. Diagnosis
Screening for pheochromocytoma consists of a 24-hour urine collection for catecholamines and metanephrines. Plasma catecholamines may also be useful; plasma norepinephrine levels greater than 2,000 pg/mL are specific for pheochromocytoma. Borderline or indeterminate results require further testing. The clonidine (Catapres) suppression test is used to confirm the diagnosis in patients with indeterminate urine or plasma studies. The test involves the measurement of plasma catecholamines before and 3 hours after 0.3 mg of oral clonidine. A normal response is a plasma norepinephrine level less than 500 pg/mL or a 50% decrease from baseline. Plasma metanephrines is also an excellent screening tool. The glucagon stimulation test may also be used. An increase in blood pressure and plasma catecholamines strongly suggests pheochromocytoma. However, the sensitivity of this test is limited, and it is potentially dangerous (hypertensive crisis). Chromogranin A, a neuropeptide secreted with the catecholamines, is sensitive for pheochromocytoma but has poor specificity. It is elevated with even minor degrees of renal insufficiency and cosecreted with many hormones. Once the diagnosis is biochemically established, radiographic localization is indicated. Although CT is the initial choice, MRI may be especially useful because pheochromocytoma can be markedly hyperintense (white) on T2-weighted images. Scanning with iodine-131-labeled metaiodobenzylguanidine (MIBG) is most specific and is particularly useful for extra-adrenal (10%) and malignant metastatic tumors (10%).
mortality rates of 48% and 54.4%, respectively, in the late 1960s35 dropped to 17% and 26%, respectively, by the late 1980s.36 In a 1999 review of patients with pheochromocytoma in pregnancy, the maternal and fetal mortality rates were 4% and 11%, respectively. Antenatal diagnosis of pheochromocytoma reduced the maternal mortality rate to 2%.37 Pregnant patients with pheochromocytoma usually present with severe and fluctuating hypertension. The most common associated symptoms are headache, perspiration, palpitation, and tachycardia. Other signs and symptoms may include arrhythmias, postural hypotension, chest or abdominal pain, visual disturbance, convulsions, and sudden collapse. A history of multiple endocrine neoplasia type II (MEN II), familial pheochromocytoma, von Hippel-Lindau syndrome, or retinal angiomatosis should increase clinical suspicion. Preoperative management with alpha-adrenergic blockade (e.g., phenoxybenzamine) is safe in pregnancy. Combined alpha and beta blockers (e.g., labetalol) have also been used in pregnancy without adverse fetal effects. Beta blockade should not be used without prior alpha blockade because unopposed alphaadrenergic activity may lead to vasoconstriction and a hypertensive crisis. Surgical intervention should be performed before 24 weeks’ gestation, after achieving adequate alpha blockade. After 24 weeks’ gestation, uterine size makes abdominal exploration and access to the tumor difficult. Optimum results are obtained if surgery is delayed until fetal maturity is reached.38 At that time, with adequate alpha blockade, elective cesarean delivery may be performed, followed immediately by adrenal exploration. Vaginal delivery appears to be higher risk than cesarean delivery. Some authors have reported success with alpha and beta blockade from the beginning of the second trimester to term, with good fetal outcomes. Malignant pheochromocytoma may recur in pregnancy. Lifelong monitoring is necessary in all patients, with extra caution in those who are pregnant.
Incidentally Discovered Adrenal Mass Incidental adrenal masses are common, detected in approximately 2% of patients having abdominal CT scan. The differential diagnosis of such masses is listed in Table 22-9. Management of an incidentaloma is controversial; clinical judgment is required. Patients should first be clinically evaluated for evidence of adrenal hormone production (cortisol, androgens, aldosterone, catecholamines). If the tumor appears to be clinically
Table 22-9 Differential Diagnosis of Incidentally Found Adrenal Masses Functioning or nonfunctioning adenoma
Treatment
Functioning or nonfunctioning carcinoma
Treatment of a pheochromocytoma is resection after appropriate operative preparation (volume loading and adrenergic receptor blockade). Calcium channel blockers may also be effective.
Pheochromocytoma Metastasis from tumors at other sites (especially malignant melanoma, lung, breast, and gastrointestinal cancers) Myelolipoma Cyst
Pheochromocytoma and Pregnancy
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Pheochromocytoma in a pregnant woman is life-threatening, but the prognosis appears to be improving. Maternal and fetal
Focal enlargement in hyperplastic gland (e.g., Cushing’s disease, congenital adrenal hyperplasia) Pseudoadrenal mass arising from nearby organs
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Chapter 22 Management of Pituitary, Adrenal, and Thyroid Disease nonfunctional, most endocrinologists would still screen biochemically for pheochromocytoma.39 Several investigators also recommend dexamethasone suppression testing to exclude preclinical Cushing’s syndrome. These patients will not have the classic signs or symptoms of hypercortisolism but will have evidence of HPA axis dysfunction, such as loss of diurnal rhythm. The long-term implications of preclinical Cushing’s syndrome are unknown, and the optimal management is therefore controversial; however, at a minimum, these patients need to be identified before adrenal surgery because postoperative adrenal insufficiency may develop. Despite an absence of hormone excess, nonfunctional tumors greater than 4 to 6 cm should be resected owing to an increased risk of malignancy. Nonfunctional tumors measuring 4 cm and smaller can be further evaluated radiographically to determine the likelihood of benign disease. The attenuation value, obtained from a noncontrast CT scan, is a measure of a tumor’s lipid content. A value less than 10 Hounsfield units (HU) suggests fat density and is specific for adenoma. Masses of indeterminate attenuation value (10 to 20 HU) can be further classified by MRI. Masses inconsistent with adenoma on CT or MRI require repeated follow-up with CT to assess growth or fine-needle aspiration biopsy.40 A biopsy, however, is rarely necessary.
THYROID GLAND DISORDERS The thyroid gland is situated in the neck, anterior to the trachea, between the cricoid cartilage and the suprasternal notch. It has two lobes connected by an isthmus and in adults it usually weighs 10 to 20 grams.
Thyroid Physiology Synthesis and Secretion of Thyroid Hormone
Thyroid hormone synthesis involves six major steps: 1. Active transport of iodide across the basement membrane into the thyroid cell. The thyroid concentrates inorganic iodide from the extracellular fluid by an active process that is influenced by both thyrotropin and an autoregulatory system. Iodide transport can be inhibited by anions, as perchlorate and thiocyanate, and this mechanism has sometimes been therapeutically used to quickly correct severe hyperthyroidism in patients not manageable by other treatment. 2. Oxidation of iodide and iodination of tyrosyl residues in the thyroid gland. 3. Coupling of iodothyrosine. The two main thyroid hormones are T4 (thyroxine, 3,5,3′,5′-tetraiodo-L-thyronine) and T3 (3,5,3′-triiodothyronine). T4 and T3 form within thyroglobulin by a coupling reaction catalized by thyroid peroxidase. The thyroid can store several weeks’ supply of thyroid hormone in the thyroglobulin pool. 4. Proteolysis of thyroglobulin with release of free iodothyronines and iodothyrosines. 5. Deiodination of iodotyrosines in the thyroid cell and reuse of iodide.
6. Intrathyroidal 5′ deiodination of T4 to T3. Approximately 25% of circulating T3 is derived from direct secretion; the remainder comes from peripheral conversion. Iodine is a major component of thyroid hormone. Thus, adequate iodide intake is necessary for normal thyroid hormone synthesis. The minimum dietary requirement of iodide is about 75 μg/day; the daily iodine intake varies between 200 and 500 μg/day in the United States. Iodide absorption is efficient, and most of the iodide is removed by the thyroid and kidneys. Thyroid Hormone Transport
Thyroid hormones are transported in serum bound to carrier proteins, with only 0.03% to 0.04% of T4 and 0.3% to 0.4% of T3 being free and active. Thyroid-binding globulin (TBG) is the primary binding protein (about 75%); other binding proteins are TBPA (≈15% of T4 binding) and albumin (≈10% of T4). T3 is bound primarily to TBG. Changes in TBG concentration result in almost parallel changes in thyroid hormone concentrations, but the amount of free hormone does not change. Any alterations in the affinities of these globulins for thyroid hormone can cause significant alterations in the binding capacities, leading to changes in the ratio of free to bound thyroid hormone. TBG can be abnormal under several clinical circumstances. Congenital Thyroid Hormone Binding Protein Abnormalities
In a recent study of 15,000 consecutive patients over a period of 4 years, congenital complete TBG deficiency was reported in 1/2500 live births and partial deficiency in 1/200. TBG excess is found in 1/15,000 live births.41 Familial dysalbuminemic hyperthyroxinemia is a familial autosomal dominant syndrome caused by abnormal albumin with an increased affinity for T4 resulting in elevated serum total T4 but normal thyrotropin level. Familial dysalbuminemic hyperthyroxinemia is the most common cause of inherited euthyroid hyperthyroxinemia. Whenever there is a large discrepancy between the actual versus expected T4 in a situation of a normal thyrotropin, a binding protein abnormality is the most likely etiology. Current recommendations of using a thyrotropin level only as a screening test may result in the clinician missing these biochemical anomalies. Other causes of TBG abnormalities are pregnancy, estrogen therapy, acute hepatitis, and human immunodefieciency virus infection. Metabolism of Thyroid Hormones
T4 is metabolized by initial deiodination to T3 or reverse T3 and then later by further deiodination. The cytochrome P450 system in the liver is responsible for approximately 25% of hormone disposal. Drugs that stimulate the cytochrome P450 enzymes (phenytoin, phenobarbital, carbamazepine, rifampin) can increase thyroid hormone metabolism and clearance. In a euthyroid patient, this can be compensated by an increase in thyrotropin secretion, but in a hypothyroid patient on thyroid hormone therapy, doses would have to be increased. Several studies have demonstrated that there are two separate 5′- deiodinase enzymes and one 5-deiodinase. The type I 5′-deiodinase is primarily localized in the liver and kidney. The type II 5′-deiodinase is present in the anterior pituitary and has a much higher affinity for T4. The type II 5′-deiodinase is present in the central nervous system, placenta, and skin and it is the predominant deiodinase in the fetus.42
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Section 3 Adult Reproductive Endocrinology Approximately 80 to 90 μg of T4 is secreted daily and T3 secretion is approximately 20 to 30 μg/day. The rest comes from peripheral conversion. During illnesses, conversion of T4 can be routed preferentially to reverse T3.
Table 22-10 Screening Recommendations for Thyroid Disease Screening Recommendations
Hormone Receptors
The generally accepted concept is that T4 is a prohormone that is converted to T3, which then interacts with the nuclear receptor. Some recent work suggests that T4 may directly interact with cell membrane proteins, resulting in rapid, calcium-dependent actions. In the future, one could envision selective thyroid hormone receptor modulators, analogous to the selective estrogen receptor modulators (SERM) such as tamoxifen and raloxifene.
Physiologic Effects of Thyroid Hormone Thyroid hormone influences almost all tissues of the body, and some consider them tissue growth factors. Protein synthesis and catabolism is stimulated, and this is probably responsible for some of the calorigenic effect of thyroid hormone. Thyroid hormone also affects carbohydrate metabolism, increasing epinephrine effects in stimulating glycogenolysis and gluconeogenesis and enhancing the rate of intestinal glucose absorption. Thyroid hormone affects catabolism of all lipoproteins. Hypothyroidism can thus lead to increased levels of any of the lipoproteins, including low-density, very low-density, intermediate-density, and high-density lipoproteins. Pituitary Regulation of Thyroid Activity
Thyroid hormone synthesis and secretion is tightly regulated by pituitary thyrotropin and thus this becomes a sensitive indicator of thyroid hormone excess or deficiency. More importantly, the thyrotropin level also tells us how the pituitary perceives the thyroid status instead of relying on our own imprecise clinical impression.
Prevalence of Thyroid Disease
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The National Health and Nutrition Examination Survey (NHANES III)43 measured serum thyrotropin, total serum T4, and antithyroid antibodies in a sample representative for geographic distribution of U.S. population. The prevalence of hypothyroidism was 4.3% (0.3% clinical and 4.0% subclinical) and the prevalence of hyperthyroidism was 1.3% (0.5% clinical and 0.7% subclinical). It should be noted that mean serum thyrotropin in a healthy population was 1.5 mU/L. Thyrotropin levels were higher in females compared to males, higher in the white population than African Americans or Mexican Americans. Women were also more likely to have antithyroid antibodies. In 2004, the U.S. Preventive Health Task Force44 felt that there was insufficient “good strength” evidence to support testing or routine screening of thyroid function in the general population (Table 22-10). Most experts agree that although controversial, screening is warranted in women over age 35, men over age 65, and as routine screening in women at their first prenatal visit.45,46 The main areas of disagreement between the U.S. Preventive Task Force in 2004 and the joint statement by several endocrine associations in 200547 are
● ●
●
Organization
Routine screening for subclinical thyroid disease in adults, pregnant women, and women contemplating pregnancy
2005
Consensus statement of the American Association of Clinical Endocrinologists, The Endocrine Society, and American Thyroid Association47
Uncertain whether screening for subclinical thyroid dysfunction in nonpregnant adults is beneficial
2004
U.S. Preventive Services Task Force44
Against routine treatment of subclinical thyroid dysfunction Insufficient evidence to support population-based screening
2004
U.S. Preventive Services Task Force44
Levels of thyrotropin or free T4 should be monitored in pregnant patients with preexistent disease No need to measure TFTS in hypermesis Insufficient data to warrant routine screening of asymptomatic pregnant women
2002
American College of Obstetricians and Gynecologists45
Women and men over age 35, every 3 years
2000
American Thyroid Association107
routine screening for subclinical disease in general population routine screening for subclinical disease in women who are pregnant or planning pregnancy routine treatment of patients with subclinical hypothyroidism with thyrotropin between 4.5 and 10 mU/L.
Until more evidence is gathered through major clinical trials, patient preference will also have an important role in the decision making together with the best clinical judgment from the practicing physician.
Thyroid Disease and Fertility Menometrorrhagia may be evident in mild to moderate hypothyroidism, and amenorrhea may be observed with severe hypothyroidism. There may be disorders of ovulation or conception with hypothyroidism. Occasionally, with severe hypothyroidism, prolactin levels may be elevated, resulting in reduced LH and FSH secretion, leading to absent menses. Autoimmune ovarian problems can coexist with hypothyroidism, which may result in premature ovarian failure. Endometriosis has also been reported in antibody-positive women. Hyperthyroidism may also be associated with irregular or absent menses, and infertility is common. Thyroid disease should be considered in patients undergoing investigation for menstrual problems48 or infertility.49 A recent prospective study by Poppe and colleagues of more than 400 infertile women showed a higher prevalence of autoimmune thyroid disease (18%), determined by the presence of antimicrosomal antibodies, compared with controls (8%).50 A Finnish study reported an overall prevalence of hypothyroidism of 4% in infertile women.51 Fortunately, once treated adequately, neither hypothyroidism nor hyperthyroidism has a major impact on fertility. The potential effect of treatment of relative thyroid hormone deficiency on infertility is unknown.52 One intervention trial in
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Chapter 22 Management of Pituitary, Adrenal, and Thyroid Disease women with recurrent abortions, mild thyroid dysfunction, and positive antimicrosomal antibodies53 showed that early supplementation with thyroid hormone favorably affects the outcome of pregnancy. It is unknown whether treatment of women with antithyroid antibodies but normal thyrotropin levels can lead to better outcomes. Systematic screening54 should be considered in all women with a female cause of infertility.55
Subclinical Hypothyroidism
Table 22-11 Causes of Hypothyroidism Primary Agenesis Destruction of the gland Surgical removal Irradiation—therapeutic radioiodine or external irradiation Autoimmune disease (Hashimoto’s thyroiditis) Idiopathic atrophy Infiltrative process (as in scleroderma, Reidel’s thyroiditis) Inhibition of synthesis and release of thyroid hormone Iodine deficiency Excess iodide in susceptible individuals Drugs—interferon, lithium, amiodarone Inherited enzyme defects Transient Subacute thyroiditis Postpartum thyroiditis Silent thyroiditis
Subclinical hypothyroidism is defined as an elevated serum thyrotropin level associated with normal total or free levels of T4 and T3 in the absence of symptoms. The thyrotropin level is usually less than 10 μU/mL. It has been also called mild hypothyroidism, preclinical hypothyroidism, mild thyroid failure, and compensated hypothyroidism.56 The natural history of subclinical hypothyroidism is variable.57 In some individuals, the thyrotropin level will be normal several months later or may remain unchanged. This may be due to laboratory error or to transient silent thyroiditis. The patient may also develop overt hypothyroidism, which occurs at a rate of about 5% per year in patients with raised thyrotropin levels and detectable antithyroid antibodies.58 In some subjects with high titers of antithyroid antibodies, the risk of progression to overt disease may be closer to 20% per year.59 Consideration of these possible outcomes60 affects the decision about whether to treat or to observe without treatment.61
able to radioactive ablation, because they do not cause permanent hypothyroidism and thus would constitute a therapeutic/ diagnostic trial.
Potential Benefits of Treating Subclinical Hypothyroidism
Hypothyroidism
Treatment may prevent progression to overt hypothyroidism, which is estimated to be 2.6% in women with increased thyrotropin levels and 4.3% if antimicrosomal antibodies are present as well. The risk of cardiovascular disease may be decreased if the lipid profile is affected,62 even though several studies failed to show a clear association between cardiovascular disease and hypothyroidism.63 There may be an improvement of symptoms if present.64
Subclinical Hyperthyroidism Subclinical hyperthyroidism is defined as a suppressed serum thyrotropin level associated with normal total or free levels of T4 and T3. The prevalence (2%) is much lower compared with subclinical hypothyroidism. With or without a goiter, it is often difficult to make a definitive diagnosis, even with additional tests. If the thyrotropin level is not detectable or is at the lowest limit of normal, it is unlikely that the patient is hyperthyroid. If the thyrotropin level is only slightly below the normal range (i.e., 0.1 to 0.3 μU/mL), this is most likely a transient abnormality and should be monitored rather than treated. If the individual is truly hyperthyroid, there will be potential increased risk of atrial fibrillation, osteoporosis, and changes in heart contractility. Nevertheless, the abnormal test results may be a result of nonthyroidal illness and concomitant medication, underlying autonomous thyroid function, or the initial phase of thyroiditis. It would be reasonable to repeat thyroid function tests in 8 to 12 weeks. Normalization would indicate likely recovery from nonthyroidal illness or thyroiditis. If the initial pattern persists, the choice should be made between a trial of antithyroid drugs and close clinical follow-up. Antithyroid drugs would be prefer-
Secondary Pituitary disease—tumors, surgery or irradiation, infiltrative disorders, Sheehan’s syndrome, trauma, genetic forms of combined pituitary hormone deficiencies Hypothalamic disease
Hypothyroidism is a common disease, especially in women, with a 1% to 2% prevalence (up to 10% in those older than age 65).43,56,65 Congenital hypothyroidism is one of the most frequent congenital diseases, with an incidence of 1/4000 newborns. Table 22-11 lists the causes of hypothyroidism. Clinical Features
The symptoms are generally related not only to the pathogenesis of hypothyroidism, duration, and severity, but also to the age of the patient. The symptoms and signs of thyroid disease are ubiquitous and often nonspecific. Armed with a high index of suspicion, one can more easily document the clinical manifestations of thyroid disease. Hypothyroidism may manifest as modest weight gain; cold intolerance; fatigue; dry, falling hair; facial puffiness; macroglossia; slow, guttural speech; muscle aches; depression; reduced memory; somnolence; sleep apnea; constipation; galactorrhea; and a menstrual disorder such as menorrhagia. Clinical signs include dry and yellow skin, eyelid edema, puffy hands and swelling of feet, cold extremities, dry skin and brittle nails, coarse hair, slow speech, delayed relaxation phase of deep tendon reflexes, bradycardia, and serous cavity effusions. Despite popular belief weight gain is minimal and is due mostly to fluid retention. Since autoimmune processes play a major role in thyroid disorders, one should often look for other autoimmune disorders in the patient and enquire about family history of thyroid and other autoimmune disorders, especially in female relatives. Smoking increases the metabolic effects of hypothyroidism in a dose-dependent way. Thyroid gland examination should include the size, symmetry, consistency, tenderness, nodularity, mobility, vascularity, and any
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Section 3 Adult Reproductive Endocrinology associated lymphadenopathy. The presence of goiter is not essential for diagnosis. Laboratory Tests
The best screening test for both hypothyroidism and hyperthyroidism is the level of thyrotropin (TSH). The thyrotropin response to decreasing free T4 levels is hyperbolic. Once the patient is hypothyroid, thyrotropin rises beyond the normal range, but subsequent drops in free T4 levels can result in exponential rise in thyrotropin levels. Although the thyrotropin level is helpful in making the diagnosis of hypothyroidism, the levels of TSH do not correlate with the severity of the hypothyroidism. Once an abnormal TSH level is detected, one should confirm the diagnosis with measurement of free T4 or T3 levels. Total T4 reflects bound and free T4. T4 uptake is an estimate of binding that correlates with the amount of TBG. The free thyroxine index is a calculated value (product of total T4 and the T4 uptake). The free T4 is a direct immunoassay detecting unbound T4. This is a more economical method compared to the more accurate but laborious dialysis assay. Total T3 and free T3 are additional tests that are not immediately necessary for thyroid evaluation. Thyroglobulin levels may be high, indicating inflammation or damage to the thyroid gland, and may be low in situations of excessive exogenous thyroid hormone administration. Antithyroid Antibodies
Microsomal antibodies (or thyroid perioxisomal antibodies) usually represent underlying Hashimoto’s thyroiditis. Approximately 5% to 15% of euthyroid women and up to 2% of euthyroid men have antithyroid antibodies and these patients have an increased risk of developing thyroid dysfunction. Thyroglobulin antibodies may also be present in Hashimoto’s thyroiditis (autoimmune thyroiditis). In scenarios where thyroglobulin levels are being monitored, the presence of thyroglobulin antibodies may interfere with the thyroglobulin assay, resulting in falsely low or falsely high levels of thyroglobulin. Thyrotropin receptor antibodies are antibodies that bind to the thyrotropin receptor. Their presence signifies Graves’ disease. Some antibodies may be stimulatory, such as thyroid-stimulating immunoglobulin; others may be inhibitory (thyroid binding inhibitory immunoglobulin. Antithyroid antibodies may cross the placenta and can cause transient thyroid dysfunction in the fetus. Other Diagnostic Methods
The thyroid ultrasound examination is now widely available and is the best delineator of thyroid structure. A radioactive iodide scan can determine which areas of the thyroid are able to trap and organify iodide. Radioactive iodide uptake is a numerical (not visual) measure, describing the percentage of iodide that is being taken up specifically by the thyroid tissue. Measurements can be typically made 4 hours or later after the isotope (131I or 125I) is administered. Lipids
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An association between hypothyroidism and lipid disorder has been observed for decades, but the exact effects are still unknown. In a study on 295 patients with overt hypothyroidism, just 8.5% had a normal lipid profile.66 However, in another study of hypothyroidism in hypercholesterolemic patients (cholesterol level
over 200 mg/dL) the prevalence of overt hypothyroidism was 1.3% and subclinical hypothyroidism 11.2%.67 The effects of replacement with thyroxine are even more controversial. T4 replacement can reduce LDL cholesterol by 11% to 36%, depending on the degree of basal LDL elevation.63 Myxedema Coma
Myxedema coma is now extremely rare due to much earlier diagnosis of hypothyroidism. The patients have profound hypothermia, bradycardia, and typical skin and facial changes; mortality is close to 100% with or without treatment. Aggressive treatment with intravenous T4 (up to 500 μg) with possible addition of T3 can reduce mortality.68 Treatment
The thyroid hormone replacement preparations available are: ● ● ●
sodium levothyroxine dessicated thyroid synthetic T3 or synthetic T4/T3 combination.
The most commonly used preparation is levothyroxine, usually with a daily replacement of 1.6 μg/kg. Thyroid function tests should be assessed at 2 months, then 6 months, and then annually to monitor compliance and dosage requirements. The dosage is smaller if the patient still has residual thyroid function. Due to its short half-life, T3 is used before some diagnostic tests. There are some data indicating that adding T3 to T4 treatment will improve mood and quality of life, but other studies don’t show any beneficial effect.69 The medication should be taken at least 1 hour from a meal. Medications such as calcium, soy, iron, aluminum, and cholestyramine can interfere with the absorption or metabolism of levothyroxine, and they should be separated by 4 hours from the thyroid hormone. In elderly patients, with or without cardiac disease, a lower dose (12.5 to 25 μg/day) is started and increased slowly, by 25 μg/day every 4 to 6 weeks. Special consideration should be taken when treating pregnant women with preexistent hypothyroidism (see “Thyroid Disease in Pregnancy” in this chapter) and to treat adrenal insufficiency first in secondary hypothyroidism. The interchangeability of thyroxine products has been closely watched for several decades, but in 2004, the American Association of Clinical Endocrinologists, The Endocrine Society (TES), and the American Thyroid Association issued a joint statement addressing the introduction to the market of several generic levothyroxine products that had been approved by the U.S. Food and Drug Administration (FDA).70 The main concern was related to the FDA’s method in determining bioequivalence. Bioequivalence establishes therapeutic equivalence; this would be better reflected with an endocrine endpoint, such as serum thyrotropin, but this measurement was not used by the FDA. Thus the difference in some preparations was large (33% [uncorrected] and 12.5% to 25% [corrected for baseline values]). The panel recommended not substituting thyroxine preparations for one another, but if it is clinically indicated, then it suggested monitoring thyrotropin at 6 weeks. Estrogen Therapy
In women with hypothyroidism, estrogen therapy may increase thyroxine requirements.71 The serum TBG concentration
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Chapter 22 Management of Pituitary, Adrenal, and Thyroid Disease Table 22-12 Causes of Thyroid Hormone Overproduction Primary thyroid overproduction Thyrotropin-independent Graves’ disease Toxic multinodular goiter Toxic adenoma Metastatic thyroid carcinoma hCG-mediated thyrotoxicosis Iodide excess (jodbasedow) Thyrotropin-dependent Thyrotropin-mediated thyrotoxicosis (thyrotropin adenoma) Pituitary resistance to T4 and T3
Table 22-13 Symptoms and Signs of Thyrotoxicosis Symptoms (listed in order of prevalence)
Emotional nervousness, irritability Tremulousness Insomnia or decreased sleep requirement Palpitations or pounding of the heart Heat intolerance, sweating Weight loss with increased appetite Increased frequency of stools Polyuria Oligomenorrhea; menstrual irregularity or amenorrhea Decreased fertility Prominence of eyes, puffiness of lids Pain or irritation of eyes Blurred or double vision, decreasing acuity, decreased motility Dyspnea Less frequently, orthopnea, paroxysmal tachycardia, anginal pain
Physical Examination (listed in order of prevalence)
Tachycardia, overactive heart, widened pulse pressure, bounding pulse Goiter/thrill and bruit Fine, warm, moist skin Coarse or thinning hair Oncholysis (Plummer’s nails) Tremulousness, hyperreflexia Exophthalmos, lid edema, chemosis, extraocular muscle weakness Congestive heart failure, paroxysmal tachycardia or fibrillation Hyperkinetic behavior, thought, and speech Lymphadenopathy and occasional splenomegaly Prominence of eyes, lid lag, globe lag Decreased visual acuity, scotomata, papilledema, retinal hemorrhage, edema Pretibial myxedema Acropachy Hyperpigmentation or vitiligo Hypokalemic periodic paralysis
Thyroid destruction Subacute painful thyroiditis Painless and postpartum thyroiditis Amiodarone-induced thyroiditis Nonthyroidal excess Thyrotoxicosis factitia—excessive dose Struma ovari
increases at 6 weeks in response to estrogen, reaching a peak at 12 weeks. Serum T4 level rises in parallel. Estrogen increases serum TBG levels by increasing hepatic biosynthesis. Androgens decrease serum TBG levels.
Hyperthyroidism Hyperthyroidism may be a result of either overproduction of thyroid hormone or destruction of the thyroid gland. One may also see hyperthyroidism from exogenous (oral intake) or ectopic synthesis of thyroid hormone (struma ovari) (Table 22-12). Clinical Examination
Hyperthyroidism may manifest as involuntary weight loss; occasional hyperphagia; thin, brittle hair; reduced ability to concentrate; personality change; initial hypomanic symptoms followed by fatigue; insomnia; increased sweating; heat intolerance; fine tremor; proximal muscle weakness; tachyarrhythmia; more frequent bowel movements; lighter menses with reduced rate of ovulation; thin, brittle nails; and eye stare and lid lag. The presence of proptosis on ocular examination or pretibial myxedema (a nonpitting edema of the shins) strongly suggests Graves’ disease72 (Table 22-13). The differential diagnosis is listed in Table 22-14. Laboratory Evaluation
Finding a suppressed thyrotropin level with an elevated T4 or T3 level confirms the diagnosis of hyperthyroidism. New generations of thyrotropin assays can detect levels as low as 0.002 IU/mL. Truly hyperthyroid patients will have low thyrotropin levels that are in this range or most likely undetectable. The presence of thyrotropin receptor antibodies indicates Graves’ disease but by themselves do not indicate hyperthyroidism. Radioactive iodine uptake can help determine if the thyroid is autonomously overactive. This procedure can be performed in a nonpregnant woman but is not an option in a pregnant woman.
Family history of any thyroid disease, especially Graves’ disease Italicized items are more specific for Graves’ disease.
Table 22-14 Differential Diagnosis of Hyperthyroid Symptoms Acute psychosis Severe illness High-altitude exposure Selenium deficiency Medications Amphetamnes Iodide administration Amiodarone Gallbladder contrast High doses of propranolol Prednisone Estrogen withdrawal
Treatment Antithyroid Drugs
Thionamides, including propylthiouracil (PTU) and methimazole, are approved by the FDA for the treatment of hyperthyroidism. Both inhibit thyroid hormone synthesis by interfering with thyroid peroxidase-mediated iodination of tyrosine residues in thyroglobulin, an important step in the synthesis of T4 and T3.
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Section 3 Adult Reproductive Endocrinology PTU has an additional effect in blocking the conversion of T4 to T3. The medications may also have direct immunosuppressive effects in the thyroid, accounting for some of their effects in Graves’ disease.73 Personal preference has usually determined the initial choice of antithyroid medication. Recently methimazole has become the treatment of choice due to its better side effect profile and once-a-day schedule. The usual starting dose of methimazole is 15 to 30 mg; of PTU is 300 mg daily. After starting the treatment, close follow-up testing at 4 weeks is recommended and then every 4 to 6 weeks until euthyroidism is achieved. Some authors prefer using high doses first to block the gland and supplement with exogenous thyroid hormones,74 but these benefits have not been replicated in North America.75 There do not appear to be any good predictors of clinical remission or response to antithyroid drugs. Typically antithyroid medication is used for between 12 and 18 months. Once the medication is stopped, relapse occurs, usually within the first 3 to 6 months, but remission may last as much as 40 years. Side Effects of Antithyroid Drugs
Antithyroid drugs have a variety of minor side effects, such as skin reactions, arthralgias, gastrointestinal effects, and sialadenitis. Almost all patients taking antithyroid drugs will have transient elevation of liver transaminases within the first 2 to 6 weeks. The most fearful side effect is agranulocytosis, thought to occur in 0.3% of cases, mostly at the beginning of the treatment (first 3 months). A complete blood count is recommended after initiating therapy, but follow-up tests are not helpful because the agranulocytosis is idiosyncratic. However, all patients should be aware of this risk and should be told to stop the drug and seek urgent medical therapy if they develop sudden fever or sore throat without explanation. Rarer side effects include hepatic necrosis, vasculitis, and cholestasis.76 Radioactive Iodine
Radioactive iodine is used to definitively treat patients with hyperthyroidism.77 This will result in subsequent hypothyroidism. Radioiodine has not been shown to cause infertility or birth defects but certainly can cause fetal hypothyroidism, especially if given after the first trimester.
Thyroid Disease and Pregnancy Glinoer reported a higher miscarriage rate in patients from Belgium with antithyroid antibodies.78 However, it is unclear whether this represents a cause-effect relationship.79 A retrospective study published in 2005 reviewing 17,000 women delivering in one center found that pregnancies in women with subclinical hypothyroidism were three times more likely to be complicated by placental abruption (relative risk [RR]: 3) and two times more predisposed to premature birth (RR, 1.8).80 Thyroid Function in Pregnancy
Thyroid disorders are observed 4 to 5 times more frequently in women than in men. Consequently, physicians should be aware of the physiologic changes of thyroid function in pregnancy. Pregnancy results in a number of physiologic changes81: ●
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●
an increase in TBG due to higher levels of estrogen alterations in the requirements for iodine and an increase in urinary iodine excretion. In iodine-deficient areas, the thyroid
● ●
●
size enlarges but increasing iodine intake by 200 μg/day may prevent goitrogenic changes. changes in autoimmune regulation placenta has a role in deiodination of iodothyronines due to an increase in type II deiodinase. This leads to high reverse T3. an increase in hCG has an effect on the maternal thyroid that peaks near the end of first trimester. An increase in hCG by 10,000 U/L lowers thyrotropin by 0.1 μU/mL and raises free T4 by 0.6 pmol/L.
Total thyroid hormone (T4) is increased mostly in the first half of gestation due to a profound increase in TBG. Serum T4 levels increase between 6 and 12 weeks and slowly after that; T3 rise is more progressive. Serum T4 has a 20-fold higher affinity for TBG than T3, so the ratio between T4 and T3 is constant. The changes in TBG imply that the extrathyroidal T4 pool must increase to ensure the same free hormone level. The daily increased secretion is between 1% and 3 % until it reaches a steady state and then returns to previous levels. The free levels of T3 and T4 are maintained usually in a normal range. The indirect calculated free T4 indices are not very reliable in pregnancy. The hormonal output is regulated through the normal pituitary–thyroid feedback by thyrotropin stimulation that is minor in a patient with a normal thyroid gland.82 However, these physiologic adjustments can be “stressed” in women with any predisposition to thyroid disease. Human chorionic gonadotropin is a weak thyroid stimulator that can bind to the thyrotropin receptor. If hCG is markedly elevated (as may happen normally in a twin pregnancy) or is a more potent molecular variant, serum free T4 concentrations may increase to hyperthyroid range with temporary thyrotropin suppression.83 Immunology of Normal Pregnancy
It has been observed that most immune disorders improve during pregnancy. One cause has been postulated to be the absence of expression of the classic class I or II major histocompatibility complex (MHC) antigens on the placenta. These MHC antigens are needed to present antigenic peptides to cytotoxic cells and T-helper cells. The placenta produces human leukocyte antigen G, which binds natural killer cells and activates CD8+ T cells. The placental trophoblast cells express a Fas ligand that mediates apoptosis of Fas-expressing maternal lymphocytes, resulting in protection of the fetus. There are many conflicting data regarding the effect of pregnancy on T cells and B cells, with a profound interest in the Th2/Th1 ratio, which seems to be elevated in pregnancy.84 During pregnancy, there is also there is a large drop in antibody levels with no parallel reduction in B-cell number. Their reduced activity is correlated to the sex steroids. Within 6 months of delivery, total imunoglobulin G as well as autoantibodies rise above prepregnancy levels and we see an exacerbation of almost all autoimmune disorders. Fetal Thyroid Function
The fetal thyroid begins to function after 10 to 12 weeks of pregnancy. Thyroid hormones (mostly from the fetal thyroid and a negligible amount from the mother’s thyroid) are important for development of the fetal nervous system. Iodine in the mother’s diet readily crosses the placenta and is used by
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Chapter 22 Management of Pituitary, Adrenal, and Thyroid Disease the fetal thyroid gland to make thyroid hormone. Iodine deficiency can cause newborn hypothyroidism or mental retardation (cretinism) and is a major world health problem in underdeveloped countries. Because there is an overabundance of iodine in the American diet, disorders caused by a lack of dietary iodine rarely occur here. Low thyroid hormone concentrations in early gestation may be associated with lower IQ in children age 5 to 7.85 Some of the altered physiological development86 was also found in biochemically euthyroid women with elevated antimicrosomal antibodies.87 Planning Pregnancy for Women with Thyroid Disease
In patients with hypothyroidism the therapeutic aim is to maintain the thyrotropin level in the normal range, preferable close to 1 to 2 μU/mL.88 If a woman is hyperthyroid before pregnancy, medical treatment with PTU should be started.89 Clearly, radioactive iodine is contraindicated in pregnancy, and nonpregnant women should be advised to avoid conception for 6 to 12 months after the treatment. If a woman conceives while taking PTU the medication can be continued but adjusted to allow the thyroid hormone levels to be at the upper end of normal. Hypothyroidism in Pregnancy
Overt hypothyroidism is present in 0.3% to 0.7% of pregnancies and subclinical hypothyroidism in up to 2.5%. L-thyroxine is safe and is well absorbed during pregnancy. Some women require higher doses during their pregnancy. Physicians generally monitor the thyrotropin level two or three times during the pregnancy to detect even mild hypothyroidism and increase the L-thyroxine dose, if necessary. Several publications have shown that 35% to 62% of women with autoimmune hypothyroidism and up to 70% to 100% of athyroid women require an increase of levothyroxine dosage. A prospective study of 19 women found that an increase in the levothyroxine dose was necessary during 17 pregnancies.90 The mean levothyroxine requirement increased 47% during the first half of pregnancy (median onset of increase, 8 weeks’ gestation) and plateaued by week 16. This increased dose was maintained and required until delivery.
Hyperthyroidism in Pregnancy
Thyrotoxicosis (hyperthyroidism) during pregnancy, most often due to Graves’ disease, presents a challenge for diagnosis and treatment because of unique fetal and maternal considerations. The risk of miscarriage and stillbirth is increased if thyrotoxicosis goes untreated, and the overall risks to mother and baby further increase if the disease persists or is first recognized late in pregnancy.91 The main disorders that present with symptoms and signs of hyperthyroidism in pregnancy include Graves’ disease, silent thyroiditis, hyperemesis gravidarum, and molar pregnancy (Table 22-15). The diagnosis of hyperthyroidism is suggested by specific physical signs, such as prominent eyes, enlarged thyroid gland, and exaggerated reflexes, and is confirmed by markedly elevated serum thyroid hormone levels and a suppressed thyrotropin level. Radioactive investigations are not performed. However, because there is no fetal thyroid activity until after the end of the first trimester, there is very little iodide trapping by the fetus in early pregnancy. Later in pregnancy radioactive iodine can destroy the fetal thyroid, but this is probably not a sufficient reason to end the pregnancy, because recognition and treatment of hypothyroidism shortly after delivery usually ensures normal growth and development in the child. The treatment of choice for thyrotoxicosis during pregnancy is antithyroid medication, either PTU or methimazole,92 because radioactive iodine cannot be used. PTU remains the drug of choice, because methimazole has been associated with rare cases of aplasia cutis in some infants.93 The initial goal is to control the hyperthyroidism and then use the lowest medication dose possible to maintain serum thyroid hormone levels in the high normal range. In this way smaller doses of medications are used and thus are less likely to cause fetal hypothyroidism. If a mild allergy to one of these medications develops, the other medication may be substituted. If there is a problem with taking pills or more severe drug allergy, thyroidectomy may be performed during the second trimester but is rarely necessary. The natural course of hyperthyroidism in pregnancy is for the disease to become milder or remit totally near term.94 In many
Table 22-15 Gestational Hyperthyroidism Causes
Clinical Findings
Laboratory Evaluation
Usual Course of Disease
Graves’ Disease
Heat intolerance and tachycardia Clinically hyperthyroid
High T4 and T3 Suppressed thyrotropin Anti-thyrotropin receptor antibodies
Usually responds well to treatment during pregnancy and worsens after delivery
Gestational transient thyrotoxicosis (GTT); most severe form is hyperemesis gravidarum
Less dramatic hyperthyroidism than Graves’ disease Dramatic nausea and weight loss Vomiting not related to degree of hyperthyroidism Prevalence is much higher than that of Graves’ disease
GTT is directly related to both the amplitude and duration of peak hCG Thyrotropin low but not undetectable Thyroid hormone levels are high normal Absent thyrotropin receptor antibodies
Thyrotoxicosis transiently during the first half of gestation Therapy usually not required Suppressed thyrotropin may lag weeks after normalization of T4
Silent thyroiditis
Presence of goiter, no bruit Clinically hyperthyroid
T3/T4 ratio is normal Absent thyrotropin receptor antibodies
Diagnosis may be difficult
Molar pregnancy
Midly hyperthyroid Sonographic findings of molar pregnancy
Extremely high hCG levels Absent thyrotropin receptor antibodies
Resolves with removal of molar pregnancy
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Section 3 Adult Reproductive Endocrinology patients antithyroid medications can be tapered to low levels or even discontinued. For those patients who are not so fortunate, it is important to maintain control of the hyperthyroidism throughout pregnancy to avoid severe thyrotoxicosis (thyroid storm) developing during labor and delivery.94 If this does develop, additional acute treatment with beta-adrenergic blockers such as propranolol (Inderal) and high doses of nonradioactive iodine are used. Long-term treatment with these agents is not advised in pregnancy, because beta blockers have been associated with fetal bradycardia and occasionally intrauterine growth retardation.95 In lactating mothers, both PTU and methimazole can be safely used, their concentration in breast milk being small, with no effects on thyroid functions in the breastfed infant.96 Fetal Thyroid Disease
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Antithyroid medications, nonradioactive iodine, and maternal thyroid antibodies can all cross the placenta and cause hypothyroidism in the fetus. Nonradioactive iodine, which is present in some medications, including some cough medications, can cause a goiter in the fetus, making delivery difficult or causing respiratory obstruction. For this reason, iodine-containing drugs should never be used in pregnancy except in the case of thyroid storm. Unfortunately, there is no simple blood test to assess fetal thyroid function, although measurements of thyroid hormone or thyrotropin levels in the amniotic fluid sac have been used in research studies.97 Plain X-rays sometimes show delayed bone development in fetal hypothyroidism, but this test is usually not recommended. Screening for hypothyroidism at birth, now done routinely in North America on all babies, identifies the need for early short- or longterm thyroxine treatment, with excellent long-term follow-up results. Fetal thyrotoxicosis (hyperthyroidism) occurs occasionally due to transfer of maternal thyroid-stimulating antibodies across the placenta. Most often, the mother herself has hyperthyroidism, which is being treated with antithyroid drugs that also passively treat the baby by crossing the placenta. Sometimes, however, the mother’s thyrotoxicosis occurred in the past and was controlled by either radioactive iodine treatment or an operation in which the mother’s thyroid gland was removed. In such a situation the mother has less thyroid tissue and cannot be hyperthyroid, even though she continues to have thyroid-stimulating antibodies in her blood. Because the mother is well, fetal thyrotoxicosis may not be suspected. Clues to the presence of fetal hyperthyroidism are fetal heart rate consistently above the normal limit of 160 beats per minute and the presence of high levels of thyroid-stimulating antibodies in the mother’s blood. Recently, it has been suggested that ultrasonography of the fetal thyroid gland may be helpful in assessing fetal thyroid size.98 All women with a history of Graves’ disease should be tested for thyroid-stimulating antibodies late in pregnancy.99 The consequences of untreated fetal thyrotoxicosis include low birth weight and head size, fetal distress in labor, and neonatal heart failure and respiratory distress. Administration of antithyroid drugs to the mother during pregnancy can treat the baby in this situation. Close follow-up and continued treatment is required after delivery.
Postpartum Thyroid Disease in the Mother Preexisting Thyroid Disease
For preexisting hypothyroidism, thyroid hormone treatment is continued after delivery and breastfeeding is encouraged. Thyroid hormones do not pass into breast milk in significant amounts. Graves’ disease is prone to relapse or worsen in the postpartum period. If that happens, antithyroid drugs can be started or their dose increased, or radioactive iodine can be given if the mother is not breastfeeding. Women taking PTU may breastfeed, because little of this drug crosses into the milk. Nursing is also possible for women who take methimazole, although more of this drug is secreted into breast milk. In both cases the baby’s thyroid function should be monitored. Definitive therapy with radioactive iodine should be considered, although many breastfeeding women will wish to postpone this, because some of the mother’s radioiodine crosses into her baby through the breast milk. Postpartum Thyroiditis
Postpartum thyroiditis may occur in 8% to 10% of women.100 Thyroiditis also occurs in the nonpostpartum period, as well as in men, and is probably an autoimmune thyroid disease related to Hashimoto’s thyroiditis.101 Typically, it consists of a temporary period of hyperthyroidism lasting from 6 weeks to 3 months postpartum, followed by hypothyroidism occurring between 3 and 9 months after delivery. Women at risk include those with a previous history of postpartum thyroiditis or those who can be shown to have thyroid autoantibodies.102 Usually, no treatment or only symptomatic treatment is required for the hyperthyroid phase, and a short course of thyroxine treatment for 6 to 12 months is sufficient for the hypothyroid phase. Some women who do not recover from the hypothyroid phase will require long-term thyroid replacement therapy.103 During the first 3 months after delivery, symptoms of fatigue, depression, and impairment of memory and concentration are common and often unrelated to a woman’s thyroid hormone level. Symptoms can mimic postpartum depression and thus a high index of suspicion is needed to rule out hypothyroidism.104 It is reasonable to perform a thyrotropin level in those women who do experience emotional disorders following pregnancy.
Solitary Thyroid Nodule and Thyroid Cancer in Pregnancy A thyroid nodule may be discovered during the pregnancy, and the best way to investigate this would be an ultrasound-guided fine needle aspiration biopsy because this results in a better biopsy yield and the ultrasound can document a baseline assessment of size of the nodule. If results of the examination of the biopsy specimen is suspicious or suggestive of malignancy, necessary surgery can be performed in the second trimester; if the nodule is discovered late in pregnancy, surgery can be deferred until the postpartum period.105 History of thyroid cancer and radioactive iodide administration does not preclude conception. One normally advises a year of avoiding pregnancy after a high-dose radioactive iodine therapy for thyroid cancer. Pregnancy has not been shown to affect the course of thyroid cancer.106
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Chapter 22 Management of Pituitary, Adrenal, and Thyroid Disease MULTIPLE ENDOCRINE NEOPLASIA SYNDROMES
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The multiple endocrine neoplasia (MEN) syndromes are rare, but their recognition is crucial because it is important for treatment of the patient and recognition of their affected family members. The MEN syndromes are autosomal dominant in nature. It is essential that the treating physician be alert about their various clinical presentations and use the available molecular DNA testing for their confirmation. MEN syndromes have been divided into MEN type I and MEN type II. MEN type I includes pituitary, parathyroid, and pancreatic islet cell tumors; invariably hyperparathyroidism is the initial presenting disorder. Alterations in the menin gene (a tumor suppressor gene) have been implicated. MEN type II includes medullary carcinoma of the thyroid, hyperparathyroidism, and pheochromocytomas. Medullary carcinoma of the thyroid is often the initial illness in this syndrome. A mutation of the RET proto-oncogene appears to be strongly correlated with the presence of disease in MEN type II.
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Approximately 50% of pituitary adenomas are prolactinomas, 15% are GH-producing, 10% are corticotropin-producing, and less than 1% secrete thyrotropin. Nonfunctioning pituitary adenomas, more appropriately named nonsecretory adenomas, represent approximately 25% of pituitary tumors. The initial workup for most suspected adenomas should be limited and should include serum prolactin and insulinlike growth factor (IGF-I) level. Dopamine is the major inhibitor of prolactin secretion. Estrogens, thyrotropin-releasing hormone, and serotonin increase prolactin levels. Drugs, pregnancy, and hypothyroid disease are common causes of elevated prolactin levels. Serum prolactin level above 200 μg/L is almost always indicative of a prolactin-producing pituitary tumor. Dopamine agonists are now the first-line treatment for prolactin adenomas. During pregnancy bromocriptine can be discontinued; then the clinical status, serum prolactin levels, and visual field examinations can be followed. More than 95% of cases of acromegaly is caused by GH-secreting pituitary tumors. A single GH level is usually inadequate to establish the diagnosis of acromegaly. IGF-1 is the initial screening test for those suspected to have acromegaly. Somatostatin analogues are the most effective medical therapy available for acromegaly. Corticotropin-secreting pituitary adenoma is the most common cause of endogenous Cushing’s syndrome (60%), with the rest being adrenal (25%) or ectopic (15%) in origin.
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Twenty-four-hour urinary free cortisol measurement is the single best test for diagnosis of Cushing’s syndrome. Surgical (transsphenoidal) removal of corticotropin-secreting pituitary tumor is the treatment of choice for Cushing’s disease. Nonsecretory or glycoprotein-secreting tumors are usually clinically silent and they usually come to attention because of manifestations of mass lesion, including headache and visual field defect. Pituitary adenomas are the most common cause of hypopituitarism. Clinical adrenal insufficiency may be due to destruction of the adrenal gland itself, referred to as Addison’s disease or primary adrenal insufficiency. Clinical adrenal insufficiency may less commonly be due to a lack of either corticotropin (i.e., secondary adrenal insufficiency) or CRH. The most common cause of Addison’s disease in adults (80%) is autoimmune destruction of the adrenal gland. The cosyntropin (Cortrosyn or corticotropin) stimulation test is the gold standard for the diagnosis of adrenal insufficiency. The triad of headaches, palpitations, and diaphoresis in the presence of hypertension is classic for pheochromocytoma. The mean serum thyrotropin level in the healthy population is 1.5 mU/L, but the ranges of normal reported by laboratories are wide. Menometrorrhagia may be evident in mild to moderate hypothyroidism, and amenorrhea may be observed with severe hypothyroidism. Subclinical hypothyroidism is defined as an elevated serum thyrotropin level associated with normal total or free levels of T4 and T3 in the absence of symptoms. The best screening test for both hypothyroidism and hyperthyroidism is the level of thyrotropin. Once an abnormal thyrotropin level is detected, one should confirm the diagnosis with measurement of free T4 or T3 levels. Microsomal antibodies (or thyroid perioxisomal antibodies) usually represent underlying Hashimoto’s thyroiditis. Thyrotropin receptor antibodies are antibodies that bind to the thyrotropin receptor. Their presence signifies Graves’ disease. Antithyroid antibodies may cross the placenta and can cause transient thyroid dysfunction in the fetus. Total thyroid hormone (T4) is increased mostly in the first half of gestation due to a profound increase in thyroid-binding globulin. In pregnant patients with hypothyroidism the therapeutic aim is to maintain the thyrotropin level in the normal range, preferable close to 1 to 2 μU/mL. Many women with autoimmune hypothyroidism or athyroid women require an increase of levothyroxine dosage during pregnancy. The main disorders that present with symptoms and signs of hyperthyroidism in pregnancy include Graves’ disease, silent thyroiditis, hyperemesis gravidarum, and molar pregnancy. The treatment of thyrotoxicosis during pregnancy is propylthiouracil.
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1. Thorner MO, Vance ML, Kaws ER, et al: The anterior pituitary. In Wilson JD, Foster DW (eds). Williams Textbook of Endocrinology, 9th ed. Philadelphia, WB Saunders, 1998, pp 249–340. 2. Vance ML: Hypopituitarism. NEJM 330:1651–1662, 1994. 3. Molitch ME, Thorner MO, Wilson C: Therapeutic controversy: Management of prolactinomas. J Clin Endocrinol Metab 82:996–1000, 1997. 4. Garner PR: Pituitary disorders in pregnancy. Curr Obstet Med 1:143–178, 1991. 5. Molitch M: Evaluation and management of pituitary tumours during pregnancy. Endocr Pract 2:287–295, 1996. 6. Melmed S: Acromegaly. NEJM 322:966–977, 1990. 7. Herman-Bonest, Seliverstov M, Melmed S: Pregnancy in acromegaly: Successful therapeutic outcome. J Clin Endocrinol Metab 83:727–731, 1998. 8. Landolt AM, Schmid J, Wimpfheimer C, et al: Successful pregnancy in a previously infertile woman treated with SMS 201-995 for acromegaly. NEJM 320:671–672, 1989. 9. Rees LH, Burke CW, Chard T, et al: Possible placental origin of ACTH in normal human pregnancy. Nature 254:620–622, 1975. 10. Yanovski JA, Cutler GB, Chrousos GP, et al: Corticotropin-releasing hormone stimulation following low-dose Dexamethasone administration. A new test to distinguish Cushing’s syndrome from pseudoCushing’s states. JAMA 269:2232–2238, 1993. 11. Robert M, Leriche-Polverelli A, Namon P, et al: Gonadotropic pituitary adenoma and pregnancy. Value of bromocriptine. Presse Med 20:503, 1991. 12. Pestell RG, Best JD, Alfard FP: Lymphocytic hypophysitis. The clinical spectrum of the disorder and evidence for an autoimmune pathogenesis. Clin Endocrinol 33:457–466, 1990. 13. Kristof RA, Van Roost D, Klingmuller D, et al: Lymphocytic hypophysitis: Noninvasive diagnosis and treatment by high dose methylprednisolone pulse therapy? J Neurol Neurosurg Psychiatry 67:398–402, 1999. 14. Reusch JE, Kleinschmidt-De Masters BU, Lillehei KO, et al: Preoperative diagnosis of lymphocytic hypophysitis unresponsive to short course dexamethasone. Neurosurgery 30:268–272, 1992. 15. Sheehan HL: The recognition of chronic hypopituitarism resulting from postpartum pituitary necrosis. Am J Obstet Gynecol 111:852–854, 1971. 16. Jialal I, Desai RK, Rajput MC: An assessment of posterior pituitary function in patients with Sheehan syndrome. Clin Endocrinol 27:91, 1987. 17. Orth DN, Kovacs WJ: The adrenal cortex. In Wilson JD, Foster DW, Kronenberg HM, Larsen PR (eds). William’s Textbook of Endocrinology. 9th ed. Philadelphia, WB Saunders, 1998, pp 517–664. 18. Grinspoon SK, Biller BM: Clinical review 62: Laboratory assessment of adrenal insufficiency. J Clin Endocrinol Metab 79:923–931, 1994. 19. Byny RL: Withdrawal from glucocorticoid therapy. NEJM 1:30–32, 1975. 20. Hadden DR: Adrenal disorders of pregnancy. Endocrinol Metab Clin North Am 24:139–151, 1995. 21. Perlitz Y, Varkel J, Markovitz J, et al: Acute adrenal insufficiency during pregnancy and puerperium: Case report and literature review. Obstet Gynecol Surv 54:717–722, 1999. 22. New MI: Congenital adrenal hyperplasia. In DeGroot L (ed). Endocrinology, 3rd ed. Philadelphia, WB Saunders, 1995, pp 1813–1835. 23. Mulaikal RM, Migeon CJ, Rock JA: Fertility rates in female patients with congenital adrenal hyperplasia due to 21-hydroxylase deficiency. NEJM 316:178–182, 1987. 24. Lo JC, Grumbach MM: Pregnancy outcomes in women with congenital virilizing adrenal hyperplasia. Endocrinol Metab Clin North Am 30:207–229, 2001. 25. Mercado AB, Wilson RC, Cheng KC, et al: Prenatal treatment and diagnosis of congenital adrenal hyperplasia owing to steroid 21-hydroxylase deficiency. J Clin Endocrinol Metab 80:2014–2020, 1995. 26. Aron DC, Schnall AM, Sheeler LR: Cushing’s syndrome and pregnancy. Am J Obstet Gynecol 162:244–252, 1990.
27. Berwaerts J, Verhelst J, Mahler C, Abs R: Cushing’s syndrome in pregnancy treated by ketoconazole: Case report and review of the literature. Gynecol Endocrinol 13:175–182, 1999. 28. Bevan JS, Gough MH, Gillmer MD, Burke CW: Cushing’s syndrome in pregnancy: The timing of definitive treatment. Clin Endocrinol (Oxf) 27:225–233, 1987. 29. Laurel MT, Kabadi UM: Primary hyperaldosteronism. Endocr Prac 3:47–53, 1997. 30. Bravo EL: Primary aldosteronism: Issues in diagnosis and management. Endocrinol Metab Clin North Am 23:271–283, 1994. 31. Baron F, Sprauve ME, Huddleston JF, Fisher AJ: Diagnosis and surgical treatment of primary aldosteronism in pregnancy: A case report. Obstet Gynecol 86:644–645, 1995. 32. Keely E: Endocrine causes of hypertension in pregnancy—when to start looking for zebras. Semin Perinatol 22:471–484, 1998. 33. Wilson M, Morganti AA, Zervoudakis I, et al: Blood pressure, the renin-aldosterone system and sex steroids throughout normal pregnancy. Am J Med 68:97–104, 1980. 34. Wyckoff JA, Seely EW, Hurwitz S, et al: Glucocorticoid-remediable aldosteronism and pregnancy. Hypertension 35:668–672, 2000. 35. Schenker JG, Chowers I: Pheochromocytoma and pregnancy. Obstet Gynecol Surv 26:739–734, 1971. 36. Harper MA, Murnaghan GA, Kennedy L, et al: Phaeochromocytoma in pregnancy. BJOG 96:594–606, 1989. 37. Ahlawat SK, Jain S, Kumari S, et al: Pheochromocytoma associated with pregnancy: Case report and review of the literature. Obstet Gynecol Surv 54:728–737, 1999. 38. Sam S, Molitch ME: Timing and special concerns regarding endocrine surgery during pregnancy. Endocrinol Metab Clin North Am 32:337–354, 2003. 39. Gross MD, Shapiro B: Clinical review 50: Clinically silent adrenal masses. J Clin Endocrinol Metab 77:885–888, 1993. 40. Hamrahian A, Ioachimescu A, Remer E, et al: Clinical utility of noncontrast CT attenuation value (HU) to differentiate adrenal adenomas/ hyperplasias from nonadenomas: Cleveland Clinic experience. J Clin Endocrinol Metab 90:871–877, 2005. 41. Bhatkar S, Rajan M, Velumani A, Samuel A: Thyroid hormone binding protein abnormalities in patients referred for thyroid disorders. Ind J Med Res 120:160–165, 2004. 42. Degroot LJ, Larsen PR, Henneman G (eds): The Thyroid and Its Diseases, 6th ed. New York, Churchill Livingstone, 1996. 43. Hollowell J, Staehling N, Flanders W, et al: Serum TSH, T4, and thyroid antibodies in the United States population (1988 to 1994): National Health and Nutrition Examination Survey (NHANES III). J Clin Endocrinol Metab 87:489–499, 2002. 44. Helfand M, for the U.S. Preventive Services Task Force: Screening for subclinical thyroid dysfunction in nonpregnant adults: A summary of the evidence. Ann Intern Med 140:128–141, 2004. 45. American College of Obstetricians and Gynecologists Practice Bulletin: Clinical management guidelines for obstetrician-gynecologists. Thyroid disease in pregnancy. Obstet Gynecol 100:387, 2002. 46. Poppe K, Glinoer D: Thyroid autoimmunity and hypothyroidism before and during pregnancy. Hum Reprod Update 9:149–161, 2003. 47. Gharib H, Tuttle RM, Baskin HJ, et al: Subclinical thyroid dysfunction: A joint statement on management from the American Association of Clinical Endocrinologists, the American Thyroid Association, and the Endocrine Society. J Clin Endocrinol Metab 90:581–585, 2005. 48. Stagnaro-Green A, Glinoer D: Thyroid autoimmunity and the risk of miscarriage. Best Pract Res Clin Endocrinol Metab 18:167–181, 2004. 49. Stagnaro-Green A: Postpartum thyroiditis. Best Pract Res Clin Endocrinol Metab 18:303–316, 2004. 50. Poppe K, Glinoer D, Van Steirteghem A, et al: Thyroid dysfunction and autoimmunity in infertile women. Thyroid 12:997–1001, 2001. 51. Arojoki M, Jokimaa V, Juuti A, et al: Hypothyroidism among infertile women in Finland. Gynecol Endocrinol 14:127–131, 2000. 52. Kalro BN: Impaired fertility caused by endocrine dysfunction in women. Endocrinol Metab Clin North Am 32:573–592, 2003.
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Chapter 22 Management of Pituitary, Adrenal, and Thyroid Disease 53. Vaquero E, Lazzarin N, De Carolis C, et al: Mild thyroid abnormalities and recurrent spontaneous abortion: Diagnostic and therapeutical approach. Am J Reprod Immunol 43:204–208, 2000. 54. Spong CY: Subclinical hypothyroidism: Should all pregnant women be screened? Obstet Gynecol 105:235–236, 2005. 55. Hollowell J, LaFranchi S, Smallridge R, et al: 2004 where do we go from here? Summary of working group discussions on thyroid function and gestational outcomes. Thyroid 15:72–76, 2005. 56. Canaris G, Manowitz N, Mayor G, Ridgway E: The Colorado thyroid disease prevalence study. Arch Intern Med 160:526–534, 2000. 57. Cooper DS: Subclinical thyroid disease: Consensus or conundrum? Clin Endocrinol 60:410–412, 2004. 58. Cooper D: Clinical practice. Subclinical hypothyroidism. NEJM 345:260–265, 2001. 59. Diez JJ, Iglesias P: Spontaneous subclinical hypothyroidism in patients older than 55 years: An analysis of natural course and risk factors for the development of overt thyroid failure. J Clin Endocrinol Metab 89:4890–4897, 2004. 60. Tuzcu A, Bahceci M, Gokalp D, et al: Subclinical hypothyroidism may be associated with elevated high-sensitive C-reactive protein (low grade inflammation) and fasting hyperinsulinemia. Endocrine J 52:89, 2005. 61. Hueston WJ, Pearson WS: Subclinical hypothyroidism and the risk of hypercholesterolemia. Ann Family Med 2:351–355, 2004. 62. Canturk Z, Cetinarslan B, Tarkun I, et al: Lipid profile and lipoprotein A as a risk factor for cardiovascular disease in women with subclinical hypothyroidism. Endocrine Res 29:307–316, 2003. 63. Biondi B, Klein I: Hypothyroidism as a risk factor for cardiovascular disease. Endocrine 24:1–13, 2004. 64. Rodondi N, Newman A, Vittinghoff E, et al: Subclinical hypothyroidism and the risk of heart failure, other cardiovascular events, and death. Arch Intern Med 165:2460–2466, 2005. 65. Tunbridge W, Evered D, Hall R, et al: The spectrum of thyroid disease in a community: The Whickham survey. Clin Endocrinol 7:481–493, 1977. 66. O’Brien T, Dinneen S, O’Brien P, Palumbo P: Hyperlipidemia in patients with primary and secondary hypothyroidism. Mayo Clinic Proc 68:860–866, 1993. 67. Bruckert E, De Gennes J, Dairou F, Turpin G: [Frequency of hypothyroidism in a population of hyperlipidemic subjects]. Presse Medicale 22:57–60, 1993. 68. Hylander B, Rosenqvist U: Treatment of myxoedema coma—factors associated with fatal outcome. Acta Endocrinologica 108:65–71, 1985. 69. Sawka A, Gerstein H, Marriott M, et al: Does a combination regimen of thyroxine (T4) and 3,5,3′-triiodothyronine improve depressive symptoms better than T4 alone in patients with hypothyroidism? Results of a double-blind, randomized, controlled trial. J Clin Endocrinol Metab 88:4551–4555, 2003. 70. Joint statement on the U.S. Food and Drug Administration’s decision regarding bioequivalence of levothyroxine sodium. Thyroid 14:486, 2004. 71. Arafah BM: Increased need for thyroxine in women with hypothyroidism during estrogen therapy. NEJM 344:1743–1749, 2001. 72. Weetman A: Graves’ disease. NEJM 343:1236–1248, 2000. 73. Cooper D: Antithyroid drugs. NEJM 352:905–917, 2005. 74. Hashizume K, Ichikawa K, Sakurai A, et al: Administration of thyroxine in treated Graves’ disease. Effects on the level of antibodies to thyroid-stimulating hormone receptors and on the risk of recurrence of hyperthyroidism. NEJM 324:947–953, 1991. 75. Rittmaster RS, Abbott EC, Douglas R: Effect of methimazole, with or without L-thyroxine, on remission rates in Graves’ disease. J Clin Endocrinol Metab 83:814–818, 1998. 76. Abraham P, Avenell A, Watson W, et al: Antithyroid drug regimen for treating Graves’ hyperthyroidism. Cochrane Database Syst Rev 2004: CD003420. 77. Cooper DS: Hyperthyroidism. Lancet 362:459–468, 2003. 78. Glinoer D: Thyroid autoimmunity and spontaneous abortion. Fertil Steril 72:373–374, 1999.
79. Haddow J: Subclinical hypothyroidism and pregnancy outcomes. Obstet Gynecol 106:198–199, 2005. 80. Casey BM, Dashe JS, Wells CE, et al: Subclinical hypothyroidism and pregnancy outcomes. Obstet Gynecol 105:239–245, 2005. 81. Larsen PR, Schlumberger MJ, Hay ID: Thyroid. In Wilson JD, Foster DW (eds). Williams Textbook of Endocrinology, 9th ed. Philadelphia, WB Saunders, 1998, pp 249–340. 82. Mandel S, Spencer C, Hollowell J: Are detection and treatment of thyroid insufficiency in pregnancy feasible? Thyroid 15:44–53, 2005. 83. Hershman JM: Physiological and pathological aspects of the effect of human chorionic gonadotropin on the thyroid. Best Prac Res Clin Endocrinol Metab 18:249–265, 2004. 84. Lazarus J, Parkes A, Premawardhana L: Postpartum thyroiditis. Autoimmunity 35:169–173, 2002. 85. LaFranchi S, Haddow J, Hollowell J: Is thyroid inadequacy during gestation a risk factor for adverse pregnancy and developmental outcomes? Thyroid 15:60–71, 2005. 86. Pop VJ, Kuijpens JL, van Baar AL, et al: Low maternal free thyroxine concentrations during early pregnancy are associated with impaired psychomotor development in infancy. Clin Endocrinol (Oxf) 50:149–155, 1999. 87. Morreale de Escobar G, Obregon MJ, Escobar del Rey F: Role of thyroid hormone during early brain development. Eur J Endocrinol 151(Suppl 3):U25–U37, 2004. 88. Mandel S: Hypothyroidism and chronic autoimmune thyroiditis in the pregnant state: Maternal aspects. Best Pract Res Clin Endocrinol Metab 18:213–224, 2004. 89. Neale D, Burrow G: Thyroid disease in pregnancy. Obstet Gynecol Clin North Am 31:893–905, 2004. 90. Alexander E, Marqusee E, Lawrence J, et al: Timing and magnitude of increases in levothyroxine requirements during pregnancy in women with hypothyroidism. NEJM 351:241–249, 2004. 91. Davis L, Lucas M, Hankins G, et al: Thyrotoxicosis complicating pregnancy. Am J Obstet Gynecol 160:63–70, 1989. 92. Wing D, Millar L, Koonings P, et al: A comparison of propylthiouracil versus methimazole in the treatment of hyperthyroidism in pregnancy. Am J Obstet Gynecol 170:90–95, 1994. 93. Milham S: Scalp defects in infants of mothers treated for hyperthyroidism with methimazole or carbimazole during pregnancy. Teratology 32:321, 1985. 94. Amino N, Tanizawa O, Mori H, et al: Aggravation of thyrotoxicosis in early pregnancy and after delivery in Graves’ disease. J Clin Endocrinol Metab 55:108–112, 1982. 95. Pruyn SC, Phelan PJ, Buchanan GC: Long-term propranolol therapy in pregnancy: Maternal and fetal outcome. Am J Obstet Gynecol 135:485–489, 1979. 96. Azizi F, Bahrainian M, Khamseh M, Khoshniat M: Intellectual development and thyroid function in children who were breast-fed by thyrotoxic mothers taking methimazole. J Pediatr Endocrinol Metab 16:1239–1243, 2003. 97. Nachum ZRY, Weiner E, Shalev E: Graves’ disease in pregnancy: Prospective evaluation of a selective invasive treatment protocol. Am J Obstet Gynecol 189:159–165, 2003. 98. Luton D, Le Gac I, Vuillard E, et al: Management of Graves’ disease during pregnancy: The key role of fetal thyroid gland monitoring. J Clin Endocrinol Metab 90:6093–6098, 2005. 99. Glinoer D: Management of hypo- and hyperthyroidism during pregnancy. Growth Hormone IGF Res 13(Suppl A):S45–S54, 2003. 100. Lazarus JH: Thyroid dysfunction: Reproduction and postpartum thyroiditis. Semin Reprod Med 20:381–388, 2002. 101. Pearce E, Farwell A, Braverman L: Thyroiditis. NEJM 348:2646–2655, 2003. 102. Hayslip C, Fein H, O'Donnell V, et al: The value of serum antimicrosomal antibody testing in screening for symptomatic postpartum thyroid dysfunction. Am J Obstet Gynecol 159:203–209, 1988. 103. Amino N, Mori H, Iwatani Y, et al: High prevalence of transient postpartum thyrotoxicosis and hypothyroidism. NEJM 306:849–852, 1982. 104. McCoy SJ, Beal JM, Watson GH: Endocrine factors and postpartum depression. A selected review. J Reprod Med 48:402-408, 2003.
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Section 3 Adult Reproductive Endocrinology Chapter
23
Premenstrual Syndrome and Menstrual-Related Disorders Robert L. Reid and Allison M. Case
INTRODUCTION Premenstrual syndrome (PMS) has emerged over the past 25 years as a clinical entity in search of a precise pathophysiologic explanation. A condition rarely discussed in medical texts before the 1980s, PMS can lead to major distress that interferes with day-to-day activities and disrupts interpersonal relationships. The literature on PMS has focused almost entirely on women with adverse premenstrual experiences. Some women experience well-defined medical conditions, such as migraine, epilepsy, irritable bowel syndrome, and asthma, that are linked to, and exacerbated by, the hormonal fluctuations of the menstrual cycle. However, there is evidence that 5% to 15% of women may experience positive changes in the premenstruum.1 Clinicians now understand the need to discriminate between the usual premenstrual experience of ovulatory women (wherein premenstrual molimina forewarn of impending menstruation) and PMS. This chapter reviews our current understanding of menstrual-related conditions, including PMS.
DEFINITION AND PREVALENCE Molimina Molimina are symptoms, such as breast pain, swelling, bloating, acne, and constipation, that foreshadow impending menstruation. Some or all of these symptoms are estimated to occur in 80% to 90% of women of reproductive age. Approximately 30% to 40% of women report these symptoms to be distressing enough that they would seek a remedy if one were available. Swelling of the extremities and abdominal bloating are molimina reported by 60% of women, although objective documentation of weight gain is usually lacking.2,3 Cyclic breast symptoms affect 70% of women, with 22% reporting moderate to extreme discomfort.4
Premenstrual Syndrome Premenstrual syndrome is defined as the cyclic recurrence in the luteal phase of the menstrual cycle of a combination of distressing physical, psychological, and/or behavioral changes of sufficient severity to result in deterioration of interpersonal relationships and/or interference with normal activities.5 This definition emphasizes the fact that a diagnosis of PMS should rely not only on the presence of typical premenstrual symptoms, but also on a level of severity enough to disrupt normal function. The term PMS should be reserved for a more severe constellation of symptoms, mostly psychiatric, that leads to major interference with day-to-day activities and interpersonal relationships.6 Women
with this degree of symptoms probably comprise 3% to 5% of women in their reproductive years. 7–10
Premenstrual Dysphoric Disorder In the psychiatric literature, the term premenstrual dysphoric disorder (PMDD) is used to indicate the most serious premenstrual disturbances that are associated with deterioration in functioning. PMDD is characterized by depressed or labile mood, anxiety, irritability, anger, and other symptoms occurring exclusively during the 2 weeks preceding menses. According to the American Psychiatric Association’s Diagnostic and Statistical Manual of Mental Disorders, 4th ed (DSM-IV), the symptoms must be severe enough to interfere with occupational and social functioning (Table 23-1).11 This sets PMDD apart from the more common PMS, as a severely distressing and disabling condition that requires treatment.
EPIDEMIOLOGY PMS-like behavior has been reported both in humans and in nonhuman primates that demonstrate menstrual cyclicity. In the nonhuman primate, zoologists have noted premenstrual changes in behavior and appetite similar to those reported by women with PMS.12,13 The availability of effective contraception since midway through the twentieth century has meant that repeated cycles of pregnancy and lactation were no longer the biological destiny of women in the developed world—and as a direct result the expected number of menstrual cycles in a woman’s lifetime increased from as few as 50 to as many as 500, with a commensurate increase in menstrual cycle-related disorders. Little is known about the inheritance of PMS. However, there is support for a genetic predisposition. Surveys have found that as many as 70% of daughters of affected mothers were themselves PMS sufferers, whereas 63% of daughters of unaffected mothers were symptom-free.14 The common belief that PMS is a disorder of the older woman may have stemmed from the fact that mood swings in the teen are less likely to be considered an effect of menstrual cyclicity and more likely to be attributed to the “hormonal swings and heartbreaks” of adolescence. There are clear examples of teens who developed severe PMS shortly after puberty. PMS sufferers often relate that symptoms become progressively worse over time and since women have increasing contact with healthcare providers for nonpregnancy-related concerns in their later reproductive years, this may account for the preponderance of older women seeking help for PMS.
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Section 3 Adult Reproductive Endocrinology Table 23-1 Diagnostic Criteria for Premenstrual Dysphoric Disorder (PMDD) 1. Timing of symptoms Symptoms are present during the last week of the luteal phase, remit within the first few days of menses, and are absent during the week following menses. The symptoms occur during most, if not all, menstrual cycles. 2. Symptoms At least five symptoms are required, including at least one of the first four symptoms: ● markedly depressed mood ● marked anxiety ● marked affective lability ● persistent and marked anger ● decreased interest in usual activities ● lethargy ● marked change in appetite ● hypersomnia or insomnia ● a sense of being overwhelmed or out of control physical symptoms 3. Severity The symptoms markedly interfere with work, school, social activities, and relationships with others. 4. Other disorders Rule out that the disorder is not merely an exacerbation of a major affective, panic dysthymic, or personality disorder, although PMDD can be superimposed on any of these disorders. 5. Confirmation of the disorder The above criteria must be confirmed by prospective daily self-rating for two consecutive menstrual cycles. Adapted from: American Psychiatric Association: Diagnostic and Statistical Manual of Mental Disorders, 4th ed. Washington, D.C. APA, 1994.
Premenstrual syndrome disappears during suppression of the ovarian cycle; for example, during hypothalamic amenorrhea due to excessive physical, or nutritional stress, during lactational amenorrhea, during pregnancy, and after menopause—either natural or induced.15,16 Interestingly, hormone therapy employing sequential progestin sometimes triggers PMS symptoms in susceptible women, whereas continuous combination hormone replacement therapy is not associated with these changes.17,18 Contrary to popular belief, there is no convincing evidence that the risk of PMS increases after pregnancy or tubal ligation. This belief probably originated when PMS symptoms reappeared and seemed acutely worse after the hormonal “protection” of preexisting pregnancy.
DIAGNOSIS History
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Physicians should make an effort to enquire about PMS symptoms as part of the menstrual and reproductive history of all women of reproductive age. For the woman with few symptoms, this provides education about PMS and may forestall fears that she is “losing her mind” should symptoms emerge in the later reproductive years. For the woman with significant symptoms this will create the opportunity for counseling and reassurance and will set the stage for establishing the diagnosis. A typical PMS sufferer may describe being a productive worker and/or a great mother for most of the month. Sometime after ovulation, however, she awakens in the morning with feelings of anger, anxiety, or sadness. At work she may experience feelings of paranoia and wonder if coworkers are conspiring against her. She may report difficulty concentrating or overreacting to minor
Table 23-2 Key Elements of a Prospective Symptom Record Used for the Diagnosis of PMS 1. Daily listing of symptoms 2. Ratings of symptom severity throughout the month 3. Timing of symptoms in relation to menstruation 4. Rating of baseline symptom severity during the follicular phase
day-to-day provocations. Though feeling inexplicably depressed, she may know inwardly that she has little in her life about which to be sad. She may report that minor things that her spouse says or that her children do are enough to trigger an exaggerated reaction at home. Although she may want to be held and comforted at such times, she reports that she cannot stand to be touched. She may try to isolate herself at these times. Occasionally depression, anger and aggression, or anxiety may be extreme, resulting in concerns for the welfare of the affected woman or her family. Caution is needed in immediately accepting such a typical history as diagnostic of PMS. Researchers have found that many psychiatric conditions worsen premenstrually, a situation referred to as premenstrual magnification. Hence, an individual with an underlying psychiatric disorder may recall and relate the symptoms that were most severe in the premenstrual week, while ignoring the lower level of symptoms that exist throughout the month.19 Prospective Symptom Record
The clinician can have confidence in the diagnosis only by obtaining a prospective symptom record over a 1- to 2-month period. Any calendar used for this purpose must obtain information on four key areas: symptoms, severity, timing in relation to the menstrual cycle, and baseline level of symptoms in the follicular phase (Table 23-2). Information should be sought about stresses related to the woman’s occupation and family life, because these may tend to exacerbate PMS. Past medical and psychiatric diagnoses may be relevant in that a variety of medical and psychiatric disorders may show premenstrual exacerbation. Typically PMS symptoms appear after ovulation and worsen progressively leading up to menstruation. Approximately 5% to 10% of PMS sufferers experience a brief burst of typical PMS symptoms coincident with the midcycle fall in estradiol that accompanies ovulation20 (Fig. 23-1). PMS symptoms resolve at varying rates after onset of menstruation. In some women there is almost immediate relief from psychiatric symptoms with the onset of bleeding; for others the return to normal is more gradual. The most severely affected women report symptoms onset shortly after ovulation (2 weeks before menstruation), resolving at the end of menstruation. Such individuals typically report having only one “good week” per month (Fig. 23-2).21 If this pattern is longstanding it becomes harder and harder for interpersonal relationships to rebound during the good week, with the result that their condition may start to take on the appearance of a chronic mood disorder. Whenever charting leaves the diagnosis in doubt, a 3-month trial of medical ovarian suppression will usually provide a definitive answer. One example of a symptom calendar is the Prospective Record of the Impact and Severity of Menstrual symptoms (PRISM)
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Chapter 23 Premenstrual Syndrome and Menstrual-Related Disorders Figure 23-1 Circulating gonadotropin, estradiol, and progesterone concentrations correlated to symptom severity in a woman with midcycle and premenstrual PMS symptoms— so-called pattern C PMS. Daily Menstrual Distress Questionnaire (MDQ) score reflects PMS symptom severity throughout the menstrual cycle. (From Reid RL: Endogenous opioid activity and the premenstrual syndrome. Lancet 2:786, 1983.)
300 PMS
LH (ng/ml)
LH
Pattern C
200
100
0
Estradiol Progesterone
200
10
100
5
0
0
P0(ng/ml)
E2 (pg/ml)
300
120 MDQ Score
100 80 60 40 20
Menses 0
2
4
Menses 6
8
10
12 14
16 18
20
22
24 26
Menses
A B C D Ovulation Figure 23-2 Four common patterns of PMS symptomatology in relation to the menstrual cycle. Note that in every case symptoms commence after ovulation. (From Reid RL: Premenstrual syndrome. In DeGroot L (ed). Endotext.com. Available at www.endotext.org. Accessed 20 December 2004.)
28
2
4
being evaluated for PMS. However, there are no characteristic physical findings in women with PMS. When seen in the follicular phase of the cycle, PMS sufferers typically appear entirely normal. Premenstrually, a woman presenting with an acute episode of PMS may appear anxious, tearful, or angry depending on the nature of her symptom complex. Organic causes of PMS-like symptoms must be ruled out. Marked fatigue may result from anemia, leukemia, hypothyroidism, or diuretic-induced potassium deficiency. Headaches may be due to intracranial lesions. Women attending PMS clinics have been found to have brain tumors, anemia, leukemia, thyroid dysfunction, gastrointestinal disorders, pelvic tumors including endometriosis, and other recurrent premenstrual phenomena, such as arthritis, asthma, epilepsy, and pneumothorax.16
Diagnostic Tests 5
calendar (Figs. 23-3 and 23-4). This instrument allows rapid visual confirmation of the nature, timing, and severity of menstrual cycle-related symptomatology and at the same time provides information on life stressors and current use of PMS therapies. Positive premenstrual changes associated with enhanced mood or performance are reported by up to 15% of women. Increased energy, excitement, and well-being have been associated with increased activity, heightened sexuality, and improved performance on certain types of tasks during the premenstrual phase.1
There is no endocrine test that helps in establishing the diagnosis in most circumstances. In a woman in whom the natural ovarian cycle has been disguised following hysterectomy a serum progesterone determination at the time of symptoms may help to confirm the link between symptoms and the luteal phase of the cycle. At times a complete blood count and/or sensitive thyrotropin level may be indicated to rule out anemia, leukemia, or thyroid dysfunction as an explanation for symptoms.
ETIOLOGY Physical Examination
A thorough physical examination, including gynecologic examination, is recommended in the assessment of all women
Since the 1950s a wide range of etiologic theories have been advanced to explain the varied manifestations of PMS. PMS has
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Section 3 Adult Reproductive Endocrinology PRISM CALENDAR BLEEDING Day of Menstrual Cycle
Name Baseline Weight On Day 1
lbs. or kg. (circle one)
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 1718 19 20 2122 232425 26 27 2829 30 3132 33 3435 36 3738 39 4041 42 43 44 45 46 47 48 49
Month May Date WEIGHT CHANGE SYMPTOMS Irritable Fatigue Inward anger Labile mood (crying) Depressed Restless Anxious Insomnia Lack of control Edema or rings tight Breast tenderness Abdominal bloating Bowels const(c) loose (l) Appetite up⇑ down⇓ Sex drive up⇑ down⇓ Chills(C) Sweats (S) Headaches Crave,sweets,salt Feel unattractive Guilty Unreasonable behavior Low self-image Nausea Menstrual cramps LIFESTYLE IMPACT Aggressive Physically towards others Verbally Wish to be alone Neglect housework Time off work Disoganized, distractable Accident prone/clumsy Uneasy about driving Suicidal thoughts Stayed at home Increased use of alcohol LIFE EVENTS Negative experience Positive experience Social activities Vigorous exercise MEDICATIONS Vitamin B6 ASA
Figure 23-3 One example of a Prospective Record of the Impact and Severity of Menstrual symptoms, the PRISM calendar, developed by Reid and Maddocks. (From Reid RL: Premenstrual syndrome. Curr Prob Obstet Gynecol Fertil 8:1–57, 1985.)
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been attributed to altered levels or ratios of estrogen and progesterone, androgen excess, fluid retention, endogenous hormone allergy, vitamin and trace element deficiencies, prolactin excess, hypoglycemia, bacterial and yeast infections, thyroid dysfunction, endogenous opiate addiction and withdrawal, abnormal metabolism of essential fatty acids leading to prosta-
glandin E1 deficiency, and altered calcium metabolism, to mention a few.15 As with other areas of confusion and uncertainty, the area of PMS is an attractive one for those promoting unorthodox treatments for personal gain. Many of the theories that underlie such interventions lack biologic plausibility and appear to have
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Chapter 23 Premenstrual Syndrome and Menstrual-Related Disorders Name
PRISM
Baseline Weight On Day 1
C ALEN D A R BLEEDING Day of Menstrual Cycle
lbs. or kg. (circle one)
x x
x x x x x x x
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 1718 19 20 2122 232425 26 27 2829 30 3132 33 3435 36 3738 39 4041 42 43 44 45 46 47 48 49
Month May Date WEIGHT CHANGE SYMPTOMS Irritable Fatigue Inward anger Labile mood (crying) Depressed Restless Anxious Insomnia Lack of control Edema or rings tight Breast tenderness Abdominal bloating Bowels const(c) loose (l) Appetite up⇑ down⇓ Sex drive up⇑ down⇓ Chills(C) Sweats (S) Headaches Crave,sweets,salt Feel unattractive Guilty Unreasonable behavior Low self-image Nausea Menstrual cramps LIFESTYLE IMPACT Aggressive Physically towards others Verbally Wish to be alone Neglect housework Time off work Disoganized, distractable Accident prone/clumsy Uneasy about driving Suicidal thoughts Stayed at home Increased use of alcohol LIFE EVENTS Negative experience Positive experience Social activities Vigorous exercise MEDICATIONS Vitamin B6 ASA
Figure 23-4
c
x
Visual inspection of a completed PRISM calendar reveals a pattern of symptoms consistent with PMS.
emerged as a means to market specific therapeutic products. Conscientious investigators have expended much effort to rigorously evaluate the promotional claims of others. Randomized, controlled trials have failed to confirm the efficacy of most of these purported treatments. Other theories, while having some biologic plausibility, have not or cannot be confirmed with available diagnostic techniques. No one theory has gained universal acceptance, although consensus
is developing that in some susceptible women normal swings in gonadal hormones22 appear to mediate changes in the activity of central neurotransmitters such as serotonin, which in turn incite profound changes in mood and behavior.23 Others have speculated a role for steroid-induced modulation of γ-aminobutyric acid receptors in the brain.24 Although it is likely that many of the physical symptoms (breast tenderness, bloating, constipation) are the direct effect of gonadal steroids, it is intriguing that
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Section 3 Adult Reproductive Endocrinology her life, and her loved ones is essential in choosing the level of intervention most appropriate to her situation.
Brain serotonin activity Estrogen Progesterone
Lifestyle Modification Strategies Communication Strategies
Menses
Critical level for
Depression Anger Anxiety
Figure 23-5 A hypothetical depiction of the interrelationship between gonadal steroid fluctuations and central changes in serotonin activity to explain the timing of symptoms in PMS. When serotonin levels or activity fall below an arbitrary level (which may be influenced by stress, heredity, or other factors), symptoms of anger, anxiety, or depression may emerge (depicted by gray areas). (From Reid RL: Premenstrual syndrome. In DeGroot L (ed). Endotext.com. Available at www.endotext.org. Accessed 20 December 2004.)
treatment of PMS with selective serotonin reuptake inhibitors (SSRIs) will ameliorate the severity of not only psychological, but also physical complaints.25 Several lines of evidence from clinical medicine support this interrelationship between estrogen or lack of estrogen effect (perhaps mediated by progestin-induced depletion of estrogen receptors) and central serotonergic activity.23 Estrogen has been shown to alleviate clinical depression in hypoestrogenic women in double-blind clinical trials.26,27 The addition of sequential progestin therapy to estrogen replacement triggers characteristic PMS-like mood disturbance in some susceptible postmenopausal women.17 Anti-estrogens given for ovulation induction may, at times, provoke profound mood disruption. Women with PMS show a surprisingly high frequency of premenstrual and menstrual hot flashes (85% of PMS sufferers vs. 15% of non-PMS controls) that are typical of those experienced by menopausal women.28,29 SSRIs have been shown to relieve hot flashes in breast cancer survivors made menopausal by chemotherapy.30 In each of these circumstances a decrease in exposure to estrogen has been linked to mood disturbance and in each case a decrease in serotonin activity (inferred from the response to SSRIs) appears to be the proximate cause (Fig. 23-5).
THERAPY
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Women who experience PMS typically report that they have tried numerous over-the-counter PMS remedies with little effect before seeking professional help. The type of health professional they consult will often define different courses of intervention at the outset—for example, a psychologist may well focus on communication, stress reduction, or assertiveness training, whereas other health practitioners may turn initially to medical interventions. No single approach works in all situations, and a careful assessment of the impact of symptoms on the woman,
When an individual is suffering to a degree that requires more than simple counseling and reassurance, measures aimed at lifestyle modification should first be explored. She should be encouraged to discuss the problem with those individuals who are central to her life, including spouse, other family members, or a sympathetic coworker. Often confrontations can be avoided if an understanding spouse or friend recognizes the cause for her upset and defers discussion of the controversial subject until another time. Strategies for stress reduction can be helpful. Communication and assertiveness may be improved with counseling. Group counseling in a program supervised by a clinical psychologist may be invaluable. Although it is useful for PMS sufferers to learn to anticipate times in the month when vulnerability to emotional upset and confrontation may be greatest, the strategy of making important decisions “only on the good days,” as espoused in some PMS clinics, falls apart if premenstrual symptoms last for more than just a few days per month. For some women premenstrual symptoms may last for a full 3 weeks, and advising them to restrict their important activities to the remaining days of the month is neither helpful nor warranted. Interventions aimed at reducing symptoms are more appropriate in this circumstance. Diet
There is a paucity of evidence to support a dietary approach to the control of PMS,31 although there are a few simple dietary measures that may afford a measure of relief for the afflicted woman. Most women with PMS, despite feelings of bloating and tension, show no absolute increase in weight, no change in girth, and no signs of peripheral edema.3 PMS sufferers commonly report cravings for salty and sweet foods, and these dietary alterations may account for unusual cases of premenstrual edema.32 Sudden shifts from low-sodium, low-carbohydrate intake to a diet high in these constituents can account for weight gain of as much as 5 kg in 24 hours.33 For this reason reduction in the intake of salt and refined carbohydrates may help prevent edema and swelling in occasional women with this manifestation of PMS. Although a link between methylxanthine intake and premenstrual breast pain has been suggested, available data are not convincing.34,35 Nevertheless, a reduction in the intake of caffeine may prove useful in women in whom tension, anxiety, and insomnia predominate. Several lines of evidence indicate that there is a tendency to increased alcohol intake premenstrually,36 and women should be cautioned that excessive use of alcohol is frequently an antecedent factor in marital discord. Anecdotal evidence suggests that small, more frequent meals may occasionally alleviate mood swings. Based on recent evidence that cellular uptake of glucose may be impaired premenstrually, there is at least some theoretical basis for this dietary recommendation.37 Carbohydrates may exhibit mood-altering effects through a number of mechanisms,38 yet attempts to improve premenstrual symptoms through dietary supplements have not been successful.39,40 Calcium supplemen-
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Chapter 23 Premenstrual Syndrome and Menstrual-Related Disorders tation has been shown to be marginally superior to placebo in a randomized, placebo-controlled trial.41
physical and some psychological manifestations of PMS with an improvement in health-related quality of life.49,50
Exercise
Pyridoxine
Regular aerobic exercise may relieve PMS symptoms, at least temporarily, in many women,42,43 and it should be recommended as part of an overall program of lifestyle modification. Some women with PMS report that exercise is an outlet for the inward anger and aggression that characterizes their symptomatology.
Published data in regard to the efficacy of pyridoxine (vitamin B6) have been contradictory51; however, this medication in proper dosages (100 mg daily) is, at worst, a safe placebo that becomes one part of an overall management plan for women with distressing molimina that should include lifestyle modification and changes in diet. Patients should be cautioned that these medications do not work for all women and that increasing the dose of pyridoxine in an effort to achieve complete relief of symptoms may lead to peripheral neuropathy. Pyridoxine should be discontinued if there is evidence of tingling or numbness of the extremities.
Medical Interventions The primary factor directing the selection of therapy should be the intensity and impact of premenstrual symptoms. Symptoms that are causing major disruption to quality of life rarely respond to lifestyle modification alone, and efforts to push this approach often do nothing more than delay effective therapy. Conversely, minor symptoms or symptoms that are short-lived each month seldom justify major medical interventions. Many times other gynecologic symptoms, such as dysmenorrhea or menorrhagia, coexist with PMS; if this is the case it is prudent to try existing therapies that may benefit more than one concern. Nonsteroidal anti-inflammatory drugs (NSAIDs) or oral contraceptives are an excellent first-line therapy in these circumstances.
Diuretics
The routine use of diuretics in the treatment of PMS should be abandoned. Most women show only random weight fluctuations during the menstrual cycle despite the common sensation of bloating. Spironolactone has been reported to alleviate symptoms in some PMS sufferers.52 Anxiolytics
Mefenamic acid (500 mg three times daily) in the premenstrual and menstrual weeks has outperformed placebo for the treatment of PMS in some but not all clinical trials.44,45 Mefenamic acid is contraindicated in women with known sensitivity to aspirin or those at risk for peptic ulcers.
Some women report overriding symptoms of anxiety and tension or insomnia in the premenstrual week.53 New short-acting anxiolytics or hypnotics such as alprazolam (0.25 mg twice daily) or triazolam (0.25 mg at bedtime), respectively, may be prescribed sparingly for such individuals.54,55 Buspirone has also proven useful for anxiety and may be particularly helpful in circumstances where SSRIs evoke sexual dysfunction.56
Oral Contraceptives
Antidepressant Therapy
Despite being one of the most commonly used medications among women of reproductive age, oral contraceptive steroids have been given to women with premenstrual complaints for 40 years without a clear understanding of what to expect in terms of symptom duration or severity. Contraceptive steroids will reduce menstrual cramps and flow and by so doing may improve the entire premenstrual/menstrual experience for some women. However, the very reason that some women stop oral contraceptives is that it seems to provoke a worsening of premenstrual complaints; some reports suggest that premenstrual symptoms may have an earlier onset in the cycle in some affected women using standard oral contraceptives. The first systematic studies to examine the effects of oral contraceptives on PMS did not find differences in PMS symptoms between oral contraceptive users and nonusers, nor were there significant differences between agents with differing progestational potencies.46,47 Monophasic and triphasic preparations showed similar rates of symptomatology.48 A new oral contraceptive preparation containing a novel progestin with diuretic effects (drospirenone) has undergone the most rigorous testing in normal women and women with strictly defined PMDD. The dosage of progestin in each pill is said to be the equivalent to 25 mg of spironolactone. Alhough the evidence supporting a role for fluid retention as an etiologic component of PMS is lacking,3 many women are distressed by feelings of bloating and edema. In controlled clinical trials this new oral contraceptive has been shown to offer relief to some
A range of newer antidepressant medications that augment central serotonin activity have been shown to alleviate severe PMS.57,58 Because these agents will also relieve endogenous depression, a pretreatment diagnosis achieved by prospective charting is very important. For patients in whom psychiatric symptoms predominate, antidepressant therapy may provide excellent results (Fig. 23-6). SSRIs, such as fluoxetine, sertraline, paroxetine,
Nonsteroidal Anti-inflammatory Drugs
Brain serotonin activity Estrogen Progesterone
Menses SSRI effect
Brain serotonin activity
remains above critical threshold
Figure 23-6 Hypothetical depiction of how drugs that elevate serotonin activity can alleviate PMS. (From Reid RL: Premenstrual syndrome. In DeGroot L (ed). Endotext.com. Available at www.endotext.org. Accessed 1 January 2005.)
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Section 3 Adult Reproductive Endocrinology fluvoxamine, and velafaxine (a serotonin and norepinephrine reuptake inhibitor), have all been successfully employed. Symptom profiles may help in selecting the most appropriate agent (i.e., fluoxetine in patients in whom fatigue and depression predominate; sertraline if insomnia, irritability, and anxiety are paramount). SSRIs have been associated with loss of libido and anorgasmia, which are particularly distressing to this patient population, and appropriate pretreatment counseling is essential. Tricyclic antidepressants (TCAs) have not generally been effective, with the exception of clomipramine, a TCA with strong serotoninergic activity. Intolerance to the side effects of TCAs is common. Most PMS sufferers would prefer to medicate themselves only during the symptomatic phase of the menstrual cycle. Recent studies have demonstrated that luteal phase therapy may be effective for many women with PMS.59 Practically speaking, a trial of SSRI therapy should be commenced with continuous use. After a woman has determined the optimal response that can be achieved with continuous therapy, it is reasonable for her to try luteal phase-only therapy to determine if the benefit is maintained. Unfortunately, several follow-up studies have demonstrated the rapid recurrence of severe PMS attended by significant social disruption after cessation of therapy with SSRIs.60,61 Practically speaking this would mean that if this line of therapy is chosen extended treatment may be required. Gonadotropin-Releasing Hormone Agonists
Many women express reservations about the need to take SSRIs on a long-term basis. Other women find there is some loss of spontaneous emotion while using psychotropic medications; still others report that the side effects are intolerable. A different approach to the management of severe PMS has been to suppress the ovarian cycle, which is thought to incite the changes in central neurotransmitters that underlie the manifestations of PMS (Fig. 23-7). Gonadotropin-releasing hormone (GnRH) agonists effect rapid medical ovarian suppression, thereby inducing a pseudomenopause and affording relief from
Estrogen Medical Ovarian Suppression GnRH agonist and estrogen addback
Brain serotonin activity
Critical threshold below which psychiatric symptoms appear
342
Figure 23-7 Hypothetical depiction of how medical or surgical elimination of ovarian steroid fluctuations can stabilize central serotonin activity and eliminate PMS. (From Reid RL: Premenstrual syndrome. In DeGroot L (ed). Endotext.com. Available at www.endotext.org. Accessed 1 January 2005.)
PMS.62 This approach is unsatisfactory in the long term not only because of the troublesome menopausal symptoms it evokes, but also because it creates an increased risk for osteoporosis and possibly ischemic heart disease. When combined with hormone replacement therapy GnRH agonists afford excellent relief from premenstrual symptoms without the attendant risks and symptoms resulting from premature menopause. The major drawback to this therapeutic approach is the expense of medication and the need for the patient to take multiple medications on a long-term basis. Other Medical Therapy
Neither progestin therapy63,64 nor oil of evening primrose65 have been shown to be efficacious for PMS in controlled clinical trials.
Medical Management of Specific Symptoms Premenstrual Mastalgia
Premenstrual mastalgia, which affects up to 70% of women in reproductive age, may occur in isolation from other PMS symptoms and, as such, should be considered a moliminal symptom. Low doses of danazol, the synthetic analog of ethinyltestosterone, can bring about dramatic relief of mastalgia in most women.66 This medication is given at a dose of 100 mg daily for several cycles followed by maintenance doses of 50 mg daily in the luteal phase only. Higher doses of danazol (400 mg daily) may be required to relieve other PMS symptoms.67 Mastalgia may also respond to tamoxifen, a selective estrogen receptor modulator, at a dose of 10 mg daily.68 Diuretics, medroxyprogesterone acetate, and pyridoxine have not been shown to help mastalgia.
Surgical Therapy Medical approaches to PMS should be exhausted before consideration of surgery (hysterectomy and oophorectomy) for debilitating PMS. Observational trials have shown this therapy to be effective.69,70 For the woman in whom there is unequivocal documentation that premenstrual symptoms are severe and disruptive to lifestyle and relationships and in whom conservative medical therapies have failed (either due to lack of response, intolerable side effects, or prohibitive cost), the effect of medical ovarian suppression should be tested. At times this therapy (a GnRH agonist and continuous combination hormone replacement therapy) can be maintained until menopause with satisfactory symptom control. Some women, despite complete relief of symptoms, cannot afford to or choose not to take this combination of medications for prolonged intervals (as long as 10 to 15 years from diagnosis until menopause in some cases). In these specific circumstances a surgical option may be considered. In the circumstance where family is complete and permanent contraception is desired, the pros and cons of oophorectomy for lasting relief from premenstrual symptomatology should be discussed with the patient. In many women the progestin component of hormone replacement therapy when given sequentially may induce an apparent recrudescence of PMS-like symptoms and when given continuously may result in unwanted irregular bleeding. Accordingly, hysterectomy at the time of oophorectomy is a consideration that allows subsequent replacement with low-dose estrogen alone.
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Chapter 23 Premenstrual Syndrome and Menstrual-Related Disorders Table 23-3 Mechanisms and Management of Menstrual Cycle-related Effects on Common Medical Conditions Medical Condition
Mechanism
Management
Menstrual Migraine Migraines occurring only on day 1 of menstruation ± 2 days
Estrogen withdrawal
Symptomatic: ergotamine, analgesics, antiemetics, triptans Prophylactic: Estrogen (percutaneous patch or gel; oral) Cycle suppression (continuous OC, GnRH agonist) Triptans
Catamenial Epilepsy Epilepsy that worsens or occurs exclusively at menstruation
Decreased progesterone = lowered seizure threshold Altered drug metabolism
Symptomatic: Measure anticonvulsant levels and alter dose accordingly Prophylactic: Progesterone (oral, I.M.) Continuous combination OC Progestin-only OC
Premenstrual Asthma Premenstrual and/or menstrual asthma exacerbations
Progesterone-induced hyperventilation and alterations in airway responsiveness
Symptomatic: Optimize usual asthma medications Prophylactic: GnRH agonist (if lifethreatening)
Irritable Bowel Syndrome Premenstrual and/or menstrual exacerbations
Progesterone-induced changes in gut motility
Symptomatic: Antispasmodics, promotility agents, bulk-forming laxatives Serotonin-receptor antagonists Prophylactic: GnRH agonist (severe cases)
Diabetes Premenstrual and/or menstrual alterations in glycemic control
Changes in carbohydrate metabolism by unknown mechanism Altered eating control or patterns
Symptomatic: Adjust insulin accordingly Prophylactic: Awareness of altered control; adjust insulin accordingly
OC, oral contraceptive; GnRH, gonadotropin-releasing hormone
EFFECTS OF THE MENSTRUAL CYCLE ON COMMON MEDICAL CONDITIONS Menstrual Migraine There is compelling evidence supporting a relationship between reproductive hormones, particularly estrogen, and migraine headache. Table 23-3 gives an overview of mechanisms and management of menstrual cycle-related effects on common medical conditions. Migraine and Other Hormonal Events
Migraine headaches are two to three times more common in women than men,71 and their frequency increases considerably after menarche.72 Although 60% of migrainous women link attacks to menstruation,71 only 7% to 14% of women have true menstrual migraine. These women experience migraine headaches, usually without aura, almost exclusively during menses (generally day 1 ± 2 days)73,74 and are virtually free of migraines at other times of the cycle, with the exception of a small percentage of
women who experience a brief exacerbation associated with ovulation.71,72 Approximately 70% of women who experience menstrual migraine will improve during pregnancy, especially the second and third trimesters.74,75 These women may experience migraine in the postpartum period, associated with falling estrogen levels.76 Menopause and the climacteric, a time of declining estrogen levels, have a variable effect on migraine, although most women do show a decline in frequency of migraine after menopause.74,77 Oral contraceptives have variable effects on migraine frequency. Similar to menstrual migraine, some oral contraceptive users experience headaches only during the pill-free or placebo days.74,78 Role of Sex Steroids in Headache
Migraines are vascular headaches, associated with a vasoconstrictive phase followed by vasodilatation.79 Estrogen withdrawal is likely responsible for initiating some or all of these vascular effects on intracranial vessels.72,80 Estrogen affects headache by altering neurovascular activity in the brain. Exposure to migraine “triggers” in susceptible patients results in intracerebral release of serotonin, which stimulates dilation of intracerebral vessels. Vessel dilatation activates perivascular neurons, which in turn activate the trigeminal nucleus that results in headache pain. Peripheral serotonin levels affect a patient’s susceptibility to migraine triggers. High estrogen levels are associated with high peripheral serotonin levels, which reduce headache susceptibility. Conversely, when estrogen levels fall, as occurs with menses, ovulation, and postpartum, peripheral serotonin levels also decrease, increasing headache susceptibility and frequency.71,81 Cycling of estrogen levels and prepriming with high levels of estrogen is required for declining estrogen levels to modify peripheral serotonin levels and headache activity.74 In women with menstrual migraine, the onset of headache appears to be triggered by an abrupt decline in serum estrogen levels, rather than by any absolute level. Estrogen administration can preclude the expected migraine attack until the estrogen is discontinued.80,82–84 Progesterone administration, while delaying menstrual flow, does not prevent the occurrence of migraine at the expected time.80 Treatment of Menstrual Migraine
Effective treatment of menstrual migraine depends first on accurate diagnosis of migraine and on establishing a link between attacks and menstruation. This is best accomplished by prospective recording of migraine attacks and menstrual periods by the patient herself for at least 3 months. During this time, symptomatic relief of acute migraine attacks with the usual migraine therapies (ergotamine, analgesics, anti-inflammatory medications, antiemetics) can be offered. NSAIDs can also be used prophylactically, starting 2 days before menses and continuing for 4 to 6 days.85 These are particularly useful if the woman also experiences significant dysmenorrhea.74 The development of the triptans, serotonin receptor agonists, has significantly improved the management of migraine headaches.86 These medications selectively activate serotonin receptors on intracranial blood vessels and the trigeminal nerve, causing vasoconstriction of abnormally dilated intracranial vessels and inhibition of neurogenic inflammation.87 Acute attacks of menstrual migraine respond well to sumatriptan. Short-term prophylaxis with sumatriptan (2.5 mg three times daily) for 5
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Section 3 Adult Reproductive Endocrinology consecutive perimenstrual days has also proven effective in treating menstrual migraine,88,89 although the cost-effectiveness and long-term safety of this regimen requires further study.87 Prophylactic hormonal therapy to stabilize estrogen levels is indicated for women with menstrual migraine who do not experience adequate relief from symptomatic treatment.82–84,90,91 Estrogen can be administered either orally or percutaneously as a 50- or 100-μg transdermal patch or 1.5 mg of percutaneous estradiol gel.74,92 Percutaneous estrogen may be more effective because there is less variation in serum estrogen levels compared to oral preparations.74 Estrogen should be started in the late luteal phase, at least 48 hours before the anticipated onset of migraine, and should be continued for 4 to 6 days. Estradiol (1 mg) taken sublingually immediately at the onset of the headache may interrupt the usual progression to migraine.93 Medications that suppress the hypothalamic-pituitary-ovarian axis have been successful for treatment of women whose menstrual migraines are refractory to the usual therapies. The combination oral contraceptive pill can be given continuously for 3 to 4 months, followed by a withdrawal bleed and symptomatic treatment of any resulting migraine attack.91 A new 28-day oral contraceptive that maintains continuous, albeit lower, estrogen administration rather than placebo for the last 7 days is currently being developed and may be very useful for women experiencing menstrual migraine or migraine on the oral contraceptive during the usual pill-free or placebo week. Gonadotropin-releasing hormone agonists are a useful tool for both diagnosis and treatment of menstrual migraine but should be tried only after all other possible treatments have been exhausted. A recent report demonstrated dramatic success in treating menstrual migraine with GnRH agonists, combined with continuous low-dose estrogen replacement therapy.94 Women who respond to this treatment typically can expect to experience long-term relief after surgical oophorectomy with low-dose estrogen replacement therapy. Concomitant hysterectomy, although unnecessary for migraine prevention, simplifies subsequent hormone therapy, if necessary for menopausal symptoms. This “definitive” therapy should only be offered to the woman with recalcitrant menstrual migraine who has completed her childbearing.
Catamenial Epilepsy
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The term catamenial is derived from the Greek word Katamenios, which means monthly, because historically the cyclic nature of epileptic attacks was thought to be due to the cycles of the moon.95 Catamenial epilepsy is observed in 10% to 70% of epileptic women.95,96 As in menstrual migraine, the wide range in reported incidence is due to the lack of a generally accepted definition.96 Strictly defined, catamenial epilepsy is epilepsy that occurs at or worsens around menstruation, such that at least 75% of seizures occur over the 10 days beginning 4 days before menses, representing a sixfold increase in daily seizure frequency.95–97 Whereas up to 70% of epileptic women claim that their seizures are exacerbated by menstruation,96 true catamenial epilepsy can be objectively demonstrated in approximately 12%.96 Menstrual exacerbations occur with all types of seizures, although they may be more common in women with focal
epilepsy rather than generalized seizures.95 Three distinct patterns of catamenial epilepsy have been described in women with ovulatory cycles: perimenstrual, periovulatory, and luteal.98 In the most common, perimenstrual pattern, seizure frequency is greatest during the menstrual phase (day −3 to +3) compared to the midfollicular and midluteal phases. The periovulatory pattern is characterized by increased seizure frequency during the ovulatory (midcycle) phase, compared to the midfollicular and midluteal phases. In the luteal pattern, seizure frequency is greatest in the ovulatory, midluteal, and menstrual phases, compared to the midfollicular phase. Women with anovulatory cycles tend to experience an overall increase in seizure frequency throughout their cycle, compared to women with ovulatory cycles. This is very likely due to the overall lower progesterone levels that are consistent with anovulation. In contrast to the pattern seen in ovulatory women, seizures are significantly less common during menses compared with the remainder of the cycle in anovulatory women.99 Some women with epilepsy appear to be at increased risk for ovulatory dysfunction. One study identified anovulatory cycles in 35% of women with temporal lobe epilepsy, compared with 8% of controls.100 Other reproductive endocrine disorders, including polycystic ovary syndrome, hyperprolactinemia, and premature ovarian failure, appear to have a higher prevalence in women with epilepsy.101,102 Pathophysiology of Catamenial Epilepsy
Catamenial epilepsy is believed to result from cyclic alterations in both ovarian hormone levels and drug metabolism. Seizure threshold is increased by progesterone and decreased by estrogen.103 A decrease in the progesterone level, or in the progesterone to estrogen ratio, correlates with increased seizure activity.104 Seizure frequency has been shown to increase during two specific times in the menstrual cycle. The first corresponds to the rapid decrease in progesterone just prior to menses, and the second to the elevation of estrogen prior to ovulation.103 An increase in seizure frequency has also been demonstrated during anovulatory cycles when progesterone levels are relatively low.105 Altered metabolism of anticonvulsants at different times in the cycle is well established.95,106 The decrease in estrogen and progesterone at menstruation is believed to stimulate the release of hepatic monoxygenase enzymes, which accelerates anticonvulsant metabolism and increases the risk for breakthrough seizures.95,106 Treatment of catamenial epilepsy should include measurement of serum levels of anticonvulsants during times of seizure exacerbation. A supplemental daily dose of seizure medication at the time of exacerbation may improve seizure control.107 Treatment of Catamenial Epilepsy
Accurate prospective documentation of seizures in relation to menstrual periods is essential for diagnosis and before specific treatment. Many investigators have shown progesterone therapy to be beneficial.104,105,108–112 Medroxyprogesterone acetate given orally (10–40 mg daily) or intramuscularly (150 mg q 6–12 weeks) has been the most widely studied.104,105 In addition to its antiepileptic properties, progesterone given in this fashion may also reduce seizure frequency by suppressing gonadotropin release, which, in turn, lowers estrogen levels.108 More recently, natural
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Chapter 23 Premenstrual Syndrome and Menstrual-Related Disorders micronized progesterone has also proven effective treatment in some women. In one study, eight women with temporal lobe epilepsy were treated with progesterone vaginal suppositories, 50 to 400 mg every 12 hours, during the phase of highest seizure frequency. The average monthly seizure frequency declined by 68%, and overall 75% of women had fewer seizures during the 3-month study period.110,111 In another larger study of 36 women treated with sublingual progesterone, focal and generalized seizures were reduced by 68% and 57%, respectively, and 4 patients became seizure-free.113 The effects of combined oral contraceptives on seizure frequency have been inconsistent, with seizure exacerbation occurring on pill-free days in some reports.104 Uninterrupted combination oral contraceptives or the progestin-only oral contraceptive may be preferable in women with epilepsy because they result in continuous progestin exposure.114 There are few studies describing the use of GnRH agonists for the treatment of catamenial epilepsy refractory to other therapies.115,116 Although these drugs are generally effective at reducing seizure frequency, their effects on bone demineralization may preclude long-term use.
Premenstrual Asthma Up to 40% of women with asthma experience an increased frequency and severity of asthma symptoms premenstrually or at menstruation.117,118 Gibbs and coworkers119 objectively confirmed the worsening of asthmatic symptoms premenstrually by documenting significant decreases in peak expiratory flow rates. There is also some evidence that women are more likely to be hospitalized premenstrually for asthma complications, including respiratory failure.120–122 The precise etiology of premenstrual asthma remains elusive but may be related to changing levels of progesterone or prostaglandins. Progesterone level increases steadily after ovulation and falls abruptly in the days prior to menstruation. Its relaxant effect on smooth muscle contractility may contribute to cyclic changes in airway responsiveness.123 Progesterone-stimulated hyperventilation may further influence asthma, leading to symptomatic deterioration and dyspnea. A subjective increase in asthma symptoms, along with an objective increase in peak expiratory flow rates, has been demonstrated in women with premenstrual asthma; however, an associated deterioration in airway reactivity has not been shown.124 There is also no relationship between airway function and absolute levels of progesterone. Although some prostaglandins have bronchoconstrictive effects, studies have failed to show any relationship between endogenous prostaglandin synthesis and premenstrual asthma.125 Menstrual cycle-related alterations in immune mechanisms have also been suggested.126 It has been suggested that premenstrual asthma may in part be due to altered perception or heightened awareness of symptoms, perhaps related to PMS.117 An association has been reported between premenstrual asthma and symptom scores for PMS and dysmenorrhea.121 Both estrogen and progesterone can alter β2-adrenoceptor function and regulation, thereby potentiating the brochorelaxant effects of catecholamines. There are cyclic changes in β2-adrenoceptors during the menstrual cycle in normal women,
with up-regulation of receptors during the luteal phase, most likely related to progesterone.127 Interestingly, this cyclic change is lost in asthmatic women, who demonstrate a paradoxical down-regulation of receptors when exposed to progesterone.127 The altered β2-adrenoceptor function and regulation may reduce response to both endogenous and exogenous bronchdilators, thereby contributing to premenstrual asthma exacerbations.117 Treatment of Premenstrual Asthma
Proper management of premenstrual asthma requires an accurate diagnosis. A detailed history of the timing of exacerbations, accompanied by a patient diary of symptoms and peak expiratory flow rates is useful. The majority of patients will respond to increased dosages of the usual asthma medications (betaadrenergic agonists, anticholinergics, and corticosteroids) during the luteal phase.117,123 Intramuscular progesterone was shown to be effective in three women with severe, refractory premenstrual asthma, eliminating the decrease in peak flow rate, as well as reducing total corticosteroid requirement.128 Exogenously administered estradiol did not ameliorate severe premenstrual asthma in a randomized clinical trial.129 There are two reports of the successful use of a GnRH agonist for women with recurrent menstrual-related status asthmaticus.130,131 The improvements seen with high-dose progesterone and GnRH agonists may be due to the resulting profound suppression of ovarian hormone production. Although there has been interest in the use of oral contraceptives in women with premenstrual asthma, the existing studies have shown highly variable effects on asthma symptoms.132-134
Irritable Bowel Syndrome Irritable bowel syndrome (IBS) is a common functional bowel disorder, diagnosed clinically by the triad of chronic or recurrent abdominal pain, altered bowel habits, and the absence of a structural or biochemical abnormality.135,136 Up to one third of otherwise asymptomatic women report an increase in gastrointestinal symptoms before and during menstruation.137 Reports of constipation during the progesterone-dominant luteal phase and loose stools or diarrhea at the onset of menses are common. Almost 50% of women with IBS will report a similar increase in bowel symptoms, such as abdominal pain, diarrhea, and constipation.136-138 Progesterone has well-documented effects on the gastrointestinal system, including a reduction in lower esophageal sphincter tone and delayed gastric emptying.139 Delayed gastrointestinal transit time in women, particularly during the luteal phase, has also been demonstrated.140 Abrupt progesterone withdrawal may trigger an increase in bowel activity. Progesterone may also act as an endogenous antagonist of enteric nerve function.141 A recent study has shown that the exacerbation of IBS symptomatology at menses is associated with an increase in rectal sensitivity in women with IBS. A control group of healthy female volunteers did not demonstrate any changes in rectal sensitivity in relation to their menstrual cycles.142 Gastrointestinal symptoms, such as abdominal pain, diarrhea, and constipation, are consistently reported by women with IBS.137,143,144 The most dramatic changes in bowel symptoms occur at the start of menstrual flow, a time when the levels of progesterone fall, and prostaglandin E2 and F2α, powerful
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Section 3 Adult Reproductive Endocrinology stimulants of colonic contractility, rise.136 Patients with IBS, in whom the colon is hyperresponsive to a variety of stimuli, may have an exaggerated colonic response to prostaglandins released during menstruation.136 Treatment of Irritable Bowel Syndrome
Treatment of IBS is generally symptomatic, including antispasmodics, promotility agents, and bulk-forming laxatives. The theory of prostaglandin involvement in menstrual-related exacerbations of IBS raises the possibility of treatment with prostaglandin synthesis inhibitors. Although there are other effective drug therapies for IBS, including antispasmodics and the newer serotonin receptor antagonists,145 studies investigating the efficacies of these therapies in women with menstrual exacerbations of IBS are lacking. There have been several reports of successful treatment of severe, menstrually exacerbated IBS with GnRH agonists.146 With the menstrual cycle completely eliminated, these women experience significant and progressive improvement in bowel symptoms. Interestingly, many of these women experienced transient recurrence of their symptoms during the progestin phase of the estrogen and progestin addback therapy given to minimize the long-term adverse effects associated with GnRH agonists.146 It is likely that GnRH agonists have direct effects on the enteric nervous system, in addition to their indirect effects on the gut, mediated through ovarian hormone suppression.147 This possibility is supported by limited evidence that GnRH agonists provide relief from IBS in men and postmenopausal women.146 The expense and potential adverse effects of these medications will preclude prolonged use in most circumstances. Rarely, if dramatic relief results from a trial of ovarian suppression, oophorectomy may have a therapeutic role.
Diabetes
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Menstrual cycle-related alterations in glycemic control during the luteal and premenstrual phases in some women with insulindependent diabetes (IDDM) have been reported.148–150 In one observational study of 406 women with IDDM, 67% reported changes in blood glucose control and 70% reported changes during menstruation. These changes were most pronounced in women experiencing PMS or sweet cravings during this time.151,152 Deterioration in glycemic control, diabetic ketoacidosis, severe insulin reactions, and hypoglycemic episodes may occur more frequently around menstruation.153 In one exceptional case, insulin resistance and ketoacidosis recurred exclusively during menstruation.154 Altered insulin receptor binding and affinity at different times during the menstrual cycle have been reported in some155–157 but not all studies.158 Attempts to identify the hormones responsible for menstrual cycle-related changes in carbohydrate metabolism have produced conflicting results. Impaired glucose tolerance during the luteal phase is reported in healthy women without diabetes.159 Studies on the effects of oral contraceptives and progestational agents on carbohydrate metabolism also show variable effects.160–162 It is possible that even small effects of estrogen and progesterone on glucose homeostasis are exaggerated in diabetic women, in whom the normal feedback regulation between plasma glucose levels and insulin secretion is lost.149
Poor eating behavior, such as binging or increased intake of sweets, is described by many women in the luteal phase and premenstrually152 and is another possible cause for loss of glycemic control in women with diabetes. Diabetic women should be counseled regarding the possibility of altered glycemic control. They need to recognize and anticipate changes in their eating patterns. Regular glucose monitoring, with appropriate anticipatory adjustment of insulin dosage and dietary intake, is a useful management strategy.97 Ovarian suppression with GnRH agonists has been used successfully in women with recurrent life-threatening complications, such as recurrent severe insulin reactions or ketoacidosis associated with specific phases of the menstrual cycle.150
Arthritis Symptoms of rheumatoid arthritis often improve in the luteal phase when ovarian steroid production is maximal. Similarly, improvement is seen during pregnancy with exacerbation postpartum.163 A subjective increase in morning stiffness and arthritic pain during menstruation and the early follicular phase has been shown.164 Rudge and colleagues objectively documented menstrual cycle-related variations in rheumatoid arthritis by demonstrating a significant decline in mean grip strength at the start of menstruation.165 Similarly, finger joint size peaked within 6 days of the start of menses, corresponding in many cases with increased body weight.165 The abrupt decline of ovarian steroidogenesis resulting from involution of the corpus luteum is thought to be responsible for “menstrual arthritis,” a rare condition in which arthritis occurs exclusively at the time of menses.166 Cyclic alterations in rheumatoid arthritis may be attributable to menstrual cyclicity in the immune response.97 Both estrogen and progesterone have anti-inflammatory properties that may ameliorate arthritic symptoms.167 Premenstrual exacerbation of symptoms has also been attributed to altered pain perception associated with premenstrual mood alterations.165 Estrogen, either alone168 or in combination oral contraceptives,169,170 has proved beneficial for some women with rheumatoid arthritis. Oral contraceptives may delay onset of rheumatoid arthritis but do not prevent its occurrence.171,172 Estrogen therapy in postmenopausal women does not appear to protect against the occurrence of rheumatoid arthritis.168
Other Disorders The previous discussion describes the effects of the menstrual cycle on several relatively common disorders. Several rare conditions also show menstrual variation in severity. There are numerous case reports of catamenial pneumothorax, the occurrence of recurrent spontaneous pneumothorax exclusively associated with menses, possibly the result of pleural or diaphragmatic endometriosis.173,174 This has been successfully treated with GnRH agonists.175 There is some evidence that acute appendicitis presents more frequently in the luteal phase,176,177 although this could be due to the misdiagnosis of right lower quadrant pain resulting from corpus luteal cysts, leading to unnecessary appendectomy. Other disorders exacerbated by the postovulatory and premenstrual phases of the menstrual cycle include acne, endocrine allergy and anaphylaxis, hereditary angio-
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Chapter 23 Premenstrual Syndrome and Menstrual-Related Disorders edema, erythema multiforme, urticaria, aphthous ulcers, Behçet’s syndrome, acute intermittent porphyria, paroxysmal supraventricular tachycardia, glaucoma, and multiple sclerosis.123,178–182 GnRH agonists have been used for some of these conditions, in particular for recurrent anaphylaxis and acute intermittent porphyria, when symptoms are severe or disabling.183–185 In contrast to these disorders, myasthenia gravis generally improves premenstrually.186 Although one early report indicated better outcomes if breast surgery was performed in the luteal phase,187 subsequent investigators have been unable to confirm this finding.188
An Approach to Menstrual Cycle-Related Exacerbations of Medical Conditions Exacerbation of certain medical conditions at specific times during the menstrual cycle is a well-recognized phenomenon. The importance of prospective recording of symptoms in relation to the menstrual cycle to facilitate the diagnosis and treatment of menstrual cycle-related exacerbations cannot be overestimated. Where appropriate, cyclic alteration of symptomatic therapy may be sufficient for treatment. If such measures prove ineffectual, a trial of medical ovulation suppression may be warranted. If a dramatic benefit results, consideration should be given to ongoing therapy with a GnRH agonist and steroid “addback,” or to a cheaper alternative such as Depo-Provera or danazol. If these medical approaches are impractical due to cost or side effects, and the woman’s fertility aspirations have been met, consideration of hysterectomy and bilateral oophorectomy with ongoing estrogen replacement therapy is a final option.
PEARLS ●
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CONCLUSION ●
The recognition of recurrent menstrual cycle-related exacerbations of a medical disorder allows consideration of innovative treatments that alter or suppress ovarian hormone production. Elimination of ovarian cyclicity may provide dramatic relief for some women in whom standard therapies prove less than ideal.
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PMS is a term that should be reserved for a more severe constellation of symptoms—mostly psychiatric—that leads to major interference with day-to-day activities and interpersonal relationships. Only by obtaining a prospective symptom record over a 1- to 2-month period can the clinician have confidence in the diagnosis of PMS. The most severely affected women report symptoms onset shortly after ovulation (2 weeks before menstruation), resolving at the end of menstruation. In some susceptible women, normal swings in gonadal hormones appear to mediate changes in the activity of central neurotransmitters such as serotonin that in turn incite profound changes in mood and behavior. Neither progestin therapy nor oil of evening primrose have been shown to be efficacious for PMS in controlled clinical trials. A range of newer antidepressant medications that augment central serotonin activity have been shown to alleviate severe PMS. In women with menstrual migraine, the onset of headache appears to be triggered by an abrupt decline in serum estrogen levels, rather than by any absolute level. Prophylactic hormonal therapy to stabilize estrogen levels is indicated for women with menstrual migraine who do not experience adequate relief from symptomatic treatment. Menstrual exacerbations occur with all types of seizures, although they may be more common in women with focal epilepsy, rather than generalized seizures. Menstrual cycle-related alterations in glycemic control during the luteal and premenstrual phases in some women with insulin-dependent diabetes (IDDM) have been reported. Symptoms of rheumatoid arthritis often improve in the luteal phase when ovarian steroid production is maximal.
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44. Mira M, McNeil D, Fraser IS, et al: Mefenamic acid in the treatment of premenstrual syndrome. Obstet Gynecol 68:395–398, 1986. 45. Wood C, Jakubowicz D: The treatment of premenstrual symptoms with mefenamic acid. BJOG 87:627–630, 1980. 46. Bancroft J, Rennie D: The impact of oral contraceptives on the experience of perimenstrual mood, clumsiness, food craving and other symptoms. J Psychosom Res 37:195–202, 1993. 47. Andersch B: The effect of various oral contraceptive combinations on premenstrual symptoms. Int J Gynaecol Obstet 20:463–469, 1982. 48. Graham CA, Sherwin BB: A prospective study of premenstrual symptoms using a triphasic oral contraceptive. J Psychosom Res 36:257–266, 1992. 49. Freeman EW: Evaluation of a unique oral contraceptive in the management of premenstrual dysphoric disorder. Eur J Contracep Reprod Health 7(Suppl 3):27–34, 2002. 50. Yonkers KA, Brown C, Pearlstein TB, et al: Efficacy of a new low-dose oral contraceptive with drospirenone in premenstrual dysphoric disorder. Obstet Gynecol 106(3):492–501, 2005. 51. Wyatt KM, Dimmock PW, Jones PW, et al: Efficacy of vitamin B6 in treatment of premenstrual syndrome: Systematic review. BMJ 318:1375–1381, 1999. 52. O’Brien PM, Craven D, Selby C, et al: Treatment of premenstrual syndrome by spironolactone. BJOG 86:142–147, 1979. 53. Mauri M, Reid RL, MacLean AW: Sleep in the premenstrual phase: A self-report study of PMS patients and normal controls. Acta Psychiat Scand 78:82–86, 1988. 54. Harrison WM, Endicott J, Nee J: Treatment of premenstrual dysphoria with alprazolam: A controlled study. Arch Gen Psychiatry 47:270–275, 1990. 55. Berger CP, Presser B: Alprazolam in the treatment of two subsamples of patients with late luteal phase dysphoric disorder: A double blind placebo controlled crossover study. Obstet Gynecol 84:379–385, 1994 56. Landen M, Eriksson O, Sundblad C, et al: Compounds with affinity for serotonergic receptors in the treatment of premenstrual dysphoria: A comparison of buspirone, nefazodone and placebo. Psychopharmacology 155:292–298, 2001. 57. Steiner M, Korzekwa M, Lamont J, et al: Fluoxetine in the treatment of premenstrual dysphoria. NEJM 332:1529–1534, 1995. 58. Dimmock PW, Wyatt KM, Jones PW, et al: Efficacy of selective serotonin-reuptake inhibitors in premenstrual syndrome: A systematic review. Lancet 356:1131–1136, 2000: 59. Steiner M, Korzekwa M, Lamont J, et al: Intermittent fluoxetine dosing in the treatment of women with premenstrual dysphoria. Psychopharmacology Bull 33:771–774, 1997. 60. Pearlstein T, Joliat MJ, Brown EB, et al: Recurrence of symptoms of premenstrual dysphoric disorder after cessation of luteal phase fluoxetine treatment. Am J Obstet Gynecol 188:887–895, 2003. 61. Freeman EW, Sondheimer SJ, Rickels K, et al: A pilot naturalistic follow-up of extended sertraline treatment for severe premenstrual syndrome. J Clin Psychopharmacol 24:351–353, 2004. 62. Wyatt KM, Dimmock PW, Ismail KM, et al: The effectiveness of GnRH agonists with and without “add-back” therapy in treating premenstrual syndrome: A meta-analysis. BJOG 111:585–593, 2004. 63. Maddocks S, Hahn P, Moller F, et al: A double-blind placebo-controlled trial of progesterone vaginal suppositories in the treatment of premenstrual syndrome. Am J Obstet Gynecol 154:573–581, 1986. 64. Wyatt K, Dimmock P, Jones P, et al: Efficacy of progesterone and progestogens in management of premenstrual syndrome: Systematic review. BMJ 323:776–780, 2001. 65. Budeiri D, Li Wan Po A, Dornan JC: Is evening primrose oil of value in the treatment of premenstrual syndrome? Controlled Clin Trials 17:60–68, 1996. 66. Gorins A, Perret F, Tourant B, et al: A French double-blind crossover study (danazol versus placebo) in the treatment of severe fibrocystic breast disease. Eur J Gynaecol Oncol 5:85–89, 1984. 67. Hahn PM, Van Vugt DA, Reid RL: A randomized placebo controlled crossover trial of danazol for the treatment of premenstrual syndrome. Psychoneuroendocrinology 20:193–209, 1995.
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96. Duncan S, Read CL, Brodie MJ: How common is catamenial epilepsy? Epilepsia 34:827–831, 1993. 97. Ensom MHH: Gender-based differences and menstrual cycle-related changes in specific diseases: Implications for pharmacotherapy. Pharmacotherapy 20:523–539, 2000. 98. Herzog AG, Klein P, Ransil BJ: Three patterns of catamenial epilepsy. Epilepsia 38:1082–1088, 1997. 99. Bauer J, Burr W, Elger CE: Seizure occurrence during ovulatory and anovulatory cycles in patients with temporal lobe epilepsy: A prospective study. Eur J Neurol 5:83–88, 1998. 100. Cummings LN, Giudice L, Morrell MJ: Ovulatory function in epilepsy. Epilepsia 36:355–359, 1995. 101. Klein P, Serje A, Pezzullo JC: Premature ovarian failure in women with epilepsy. Epilepsia 42:1584–1589, 2001. 102. Isojarvi JI: Reproductive dysfunction in women with epilepsy. Neurology. 61(6 Suppl 2):S27–S34, 2003. 103. Backstrom T: Epileptic seizures in women related to plasma estrogen and progesterone during the menstrual cycle. Acta Neurol Scand 54:321–347, 1976. 104. Zimmerman AW: Hormones and epilepsy. Neurol Clin 4:853–861, 1986. 105. Mattson RH, Kamer JM, Cramer JA, et al: Seizure frequency and the menstrual cycle: A clinical study. Epilepsia 22: 242, 1981. 106. Kumar N, Behari M, Aruja GK, et al. Phenytoin levels in catamenial epilepsy. Epilepsia 29:155–158, 1988. 107. Liporace JD: Women’s issues in epilepsy: Menses, childbearing and more. Postgrad Med 102:123–135, 1997. 108. Bäckström T, Zetterlund B, Blom S, et al: Effects of intravenous progesterone infusions on the epileptic discharge frequency in women with partial epilepsy. Acta Neurol Scand 69:240–248, 1984. 109. Dana-Haeri J, Richens A: Effect of norethisterone on seizures associated with menstruation. Epilepsia 24:377–381, 1983. 110. Herzog AG: Intermittent progesterone therapy and frequency of complex partial seizures in women with menstrual disorders. Neurology 36:1607–1610, 1986. 111. Herzog AG: Intermittent progesterone therapy of partial complex seizures in women with menstrual disorders. Neurology 36:1607–1610, 1986. 112. Herzog A: Progesterone therapy in women with epilepsy: A 3-year follow-up. Neurology 52: 1917–1918, 1999. 113. Motta E, Rosciszewska D: Progesterone therapy in epileptic women with catamenial seizures. Epilepsia 36(Suppl 3):73, 1995. 114. Holmes GL: Effects of menstruation and pregnancy on epilepsy. Semin Neurol 8:234–239, 1988. 115. Bauer J, Wildt L, Flugel D, et al: The effect of a synthetic GnRH analogue on catamenial epilepsy: A study in ten patients. J Neurol 239:284–286, 1992. 116. Haider Y, Barnett DB: Catamenial epilepsy and goserelin. Lancet 338:1530, 1991. 117. Tan KS: Premenstrual asthma: Epidemiology, pathogenesis and treatment. Drugs 61:2079–2086, 2001. 118. Settipane RA, Simon RA: Menstrual cycle and asthma. Ann Allergy 63:373–378, 1989. 119. Gibbs CJ, Counts II, Lock R, et al: Premenstrual exacerbations of asthma. Thorax 39:833–836, 1984. 120. Hanley SP: Asthma variation with menstruation. Br J Dis Chest 75:306–308, 1981. 121. Eliasson O, Scherzer HH, DeGraff AC Jr: Morbidity in asthma in relation to the menstrual cycle. J Allergy Clin Immunol 77(1 Pt 1): 87–94, 1986. 122. Skobeloff EM, Spivey WH, Silverman R, et al: The effect of the menstrual cycle on asthma presentations in the emergency department. Arch Intern Med 156:1837–1840, 1996. 123. Boggess KA, Williamson HO, Homm RJ: Influence of the menstrual cycle on systemic diseases. Obstet Gynecol Clin North Am 17:321–342, 1990. 124. Pauli BD, Reid RL, Munt PW, et al: Influence of the menstrual cycle on airway function in asthmatic and normal subjects. Am Rev Respir Dis 140:358–362, 1989.
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149. Widom B, Diamond MP, Simonson DC: Alterations in glucose metabolism during menstrual cycle in women with IDDM. Diabetes Care 15:213–220, 1992. 150. Letterie GS, Fredlund PN: Catamenial insulin reactions treated with a long-acting gonadotropin releasing hormone agonist. Arch Intern Med 154:1868–1870, 1994. 151. Cawood EH, Bancroft J, Steel JM: Perimenstrual symptoms in women with diabetes mellitus and the relationship to diabetic control. Diabet Med 10:444–448, 1993. 152. Tomelleri R, Gruewald K: Menstrual cycle and food cravings in young college women. J Am Diet Assoc 87:311–315, 1987. 153. Walsh CH, Malins JM: Menstruation and control of diabetes. BMJ 2:177–179, 1977. 154. Hubble D: Insulin resistance. BMJ 2:1022–1024, 1954. 155. De Pirro R, Fusco A, Bertoli A, et al: Insulin receptors during the menstrual cycle in normal women. J Clin Endocrinol Metab 47:1387–1389, 1978. 156. Bertoli A, De Pirro R, Fusco A, et al: Differences in insulin receptors between men and menstruating women and influence of sex hormones on insulin binding during the menstrual cycle. J Clin Endocrinol Metab 50:246–250, 1980. 157. Moore P, Kolterman O, Weyant J, et al: Insulin binding in human pregnancy: Comparisons to the postpartum, luteal, and follicular states. J Clin Endocrinol Metab 52:937–941, 1981 158. Pedersen O, Hjolland E, Lindsskov HO: Insulin binding and action on fat cells from young healthy females and males. Am J Physiol 243: E158–E167, 1982. 159. Jarrett RJ, Graver HJ: Changes in oral glucose tolerance during the menstrual cycle. BMJ 2:528–529, 1968. 160. Diamond MP, Wentz AC, Cherrington AD: Alterations in carbohydrate metabolism as they apply to reproductive endocrinology. Fertil Steril 50:387–397, 1988. 161. Godsland IF, Crook D, Simpson R, et al: The effects of different formulations of oral contraceptive agents on lipid and carbohydrate metabolism. NEJM 323:1375–1381, 1990. 162. Spellacy WN: Carbohydrate metabolism during treatment with estrogen, progestogen, and low-dose oral contraceptives. Am J Obstet Gynecol 142:732–734, 1982. 163. Ostensen M, Aune B, Husby G: Effect of pregnancy and hormonal changes on the activity of rheumatoid arthritis. Scand J Rheumatol 12:69–72, 1983. 164. Latman NS: Relation of menstrual cycle phase to symptoms of rheumatoid arthritis. Am J Med 74:957–960, 1983. 165. Rudge SR, Kowanko IC, Drury PL: Menstrual cyclicity of finger joint size and grip strength in patients with rheumatoid arthritis. Ann Rheum Dis 42:425–430, 1983. 166. McDonagh JE, Singh MM, Griffiths ID: Menstrual arthritis. Ann Rheum Dis 52:65–66, 1993. 167. Bodel P, Dillard GM Jr, Kaplan SS, Malawista SE: Anti-inflammatory effects of estradiol on human blood leukocytes. J Lab Clin Med 80:373–384, 1970. 168. Da Silva JA, Hall GM: The effects of gender and sex hormones on outcome in rheumatoid arthritis. Baillieres Clin Rheumatol 6:196–219, 1992. 169. Kay CR, Wingrave SJ: Oral contraceptives and rheumatoid arthritis. Lancet 1(8339):1437, 1983. 170. Linos A, Worthington JW, O’Fallon WM, Kurland LT: Rheumatoid arthritis and oral contraceptives. Lancet 1:871, 1978. 171. Wingrave SJ, Kay CR: Reduction in incidence of rheumatoid arthritis associated with oral contraceptives. Lancet 1:569–571, 1978. 172. Spector TD, Hochberg MC: The protective effect of the oral contraceptive pill on rheumatoid arthritis: An overview of the analytic epidemiological studies using meta-analysis. J Clin Epidemiol 43:1221–1230, 1990. 173. Maurer ER, Schaal FA, Mendez FL: Chronic recurring spontaneous pneumothorax due to endometriosis of the diaphragm. JAMA 168:2013–2024, 1958. 174. Markham SM, Carpenter SE, Rock JA: Extrapelvic endometriosis. Obstet Gynecol Clin North Am 16:193–207, 1989.
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183. Anderson KE, Spitz IM, Sassa S, et al: Prevention of cyclical attacks of acute intermittent porphyria with a long-acting agonist of luteinizing hormone-releasing hormone. NEJM 311:643–645, 1984. 184. Meggs WJ, Pescovitz OH, Metcalfe D, et al: Progesterone sensitivity as a cause of recurrent anaphylaxis. NEJM 311:1236–1238, 1984. 185. Slater JE, Raphael G, Cutler GB, et al: Recurrent anaphylaxis in menstruating women: Treatment with a luteinizing hormone-releasing hormone agonist: A preliminary report. Obstet Gynecol 70:542–546, 1987. 186. Vijayan N, Vijayan VK, Dreyfuss PM: Acetylcholinesterase activity and menstrual remissions in myasthenia gravis. J Neurol Neurosurg Psychiatry 40:1060–1065, 1977. 187. Badue RA: Timing of surgery during the cycle and breast cancer survival. Lancet 337:1261, 1991. 188. Wobbes T, Thomas CM, Segers MF, et al: The phase of the menstrual cycle has no influence on the disease-free survival of patients with mammary carcinoma. Br J Cancer 69:599–600, 1994.
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Menopause Francisco Arredondo and James H. Liu
INTRODUCTION Natural menopause occurs between ages 45 and 55, with a median age of 51 for women in industrialized countries.1 Available evidence suggests that in less-developed countries with lower socioeconomic and nutritional level this event takes place earlier.2,3 These differences in onset of menopause support the hypothesis that menopause might not only be genetic, but may also be a biological marker echoing society’s longevity. The significant medical and technologic gains of the past century in medicine and to some extent, the constant betterment of living standards, have yielded an improvement in life expectancy. In some countries increases of more than 40 years of life expectancy have been observed during the past 100 years alone.4 The life expectancy for women at birth in the United States is age 79.9.5 As a consequence of this demographic evolution, a large proportion of the female population will spend more than one third of their lives after the menopause. In 1950 there were 220 million women in the world older than age 50. More than half of these women lived in the so-called developed world (112 million). In 1990, there were 467 million women older than age 50 around the globe, and by 2030 this number is expected to approach 1.2 billion. Roughly three out of four of these menopausal women will be in the developing world (total of 912 million).6 At a national level, the U.S. Census Bureau calculated a total of 35.5 million women older than age 50 during the 1990 census, and by 1997 the menopausal population in the United States represented almost 30% of the total female population. By 2030, the menopausal population in the United States is expected to reach 66.5 million, representing 38% of the female population and 20 % of the entire population.7 These demographic changes will reflect an “inverted pyramid” phenomenon in certain countries. In this scenario, the elderly to nonelderly population ratio will significantly change, with obvious challenging consequences in the economic balance between productivity and expenditure. For these reasons understanding the menopausal state, associated diseases, and its full impact to society are fundamental for health providers and health policy makers. The present chapter aims at providing an overview of this challenge.
MENOPAUSE PHYSIOLOGY AND PATHOPHYSIOLOGY The supply of primordial follicles in the female gonad is predetermined before birth and diminishes with age until the gonad
is unable to provide enough mature follicles to sustain menstrual cyclicity.8 The peak number of germ cell count is found at 20 weeks’ gestation, with decreased numbers at birth and puberty. Based on the number of follicles at three successive stages of development, which were obtained by counting follicles in histologic sections of ovaries from 52 normal women, a mathematical model was developed to describe the rates of growth and death of ovarian follicles in human ovaries between ages 19 and 50.9 While the number of oocytes dwindles throughout a woman’s life,10 there seems to be a transition at age 38 when the rate of follicle disappearance is augmented considerably with age. As a consequence, an estimated total of 1500 follicles remain at age 50 from the 300,000 present at age 19. This high death rate of small follicles appears to be responsible for advancing the timing of ovarian failure, and therefore of menopause, to midlife in our species.
Age of Menopause The mean age of menopause in normal women in the United States ranges between age 50 and 52.11 This number was based on a cross-sectional study, which is associated with recall bias. However, these findings have been confirmed in a large prospective cohort study of middle-aged women: the Massachusetts Women’s Health Study. The cohort of 2570 women that was followed confirmed that the median age of natural menopause was 51.3 years with a mean difference of 1.8 years between current smokers and nonsmokers. This study also showed that smokers not only show an earlier menopause, but also a shorter perimenopause.12 In other parts of the world, population-based surveys have shown earlier onset of menopause. For example, the median age of onset of menopause was 48 in a survey of 742 United Arab Emirates women.13 In certain regions of India, such as the state of Himachal Pradesh, the mean age of onset of menopause can be as low as 43.5 years, according to data from 500 postmenopausal women.14
Factors Affecting the Onset of Menopause Table 24-1 includes several factors that have been linked with an earlier onset of menopause. Among these factors, smoking has been the most often linked environmental agent to early age of onset of menopause. However, these studies have been inconclusive with regard to duration and intensity of smoking. Midgette and Baron concluded after a review of 14 studies that the risk of being menopausal was approximately doubled for current smokers compared with nonsmokers among women age 44 to
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Section 3 Adult Reproductive Endocrinology 55.15 However, in 2004 van Asselt and colleagues, using data from a Dutch population-based cohort of 5544 women, assessed the effect of smoking duration and intensity on age at menopause, correcting for the chronologic age-dependency of the variables concerned. After their modeling they concluded like previous researchers that smoking lowers the menopausal age. However, the reduction in the menopausal age appears not to be dependent on smoking duration, and it appears that smoking cigarettes could have an effect only around the time of menopause itself.16 In other words, the number of cigarettes smoked during perimenopause is apparently more significant than smoking history as the culprit of earlier age of onset of menopause among smoking women. Women treated with total abdominal hysterectomy appear to be at risk of early menopause. Concurrent unilateral oophorectomy was associated with an even earlier onset. However, previous tubal ligation does not influence the age of menopause.
percent of apoptosis occurs at the small antral follicle stage of 2.1 to 5 mm. On the other hand, atresia of the resting follicles in the human fetus seems to be set off by a process of necrosis rather than apoptosis.20 It seems clear now that the age-related decline in ovarian function in women is the result of the decline in both quantity and quality of the resting ovarian follicle pool. Recently a total of 182 resting follicles from a young cadre of women (age 25–32) were compared with 81 resting follicles from an older group (age 38–45) for signs of age-related changes by transmission-electron microscopy. De Bruin and colleagues concluded that, in resting follicles, the morphologic changes with age are different from the changes seen in quality decline by atresia.20 The morphologic changes with age specifically comprise the mitochondria, the dilated smooth endoplasmic reticulum, and the Golgi complex.
Genetic Contribution The age of natural menopause is determined by the interplay of genetic and environmental factors.21 There are cross-sectional22 and case-control23 population studies suggesting the existence of genetic variability in the age of menopause to be as high as 70%. However, a study conducted in the Netherlands in 164 motherdaughter pairs with a natural menopausal age estimated a hereditability of 44% (95% confidence interval [CI] 36%–50%). The authors conclude that these estimates are more accurate than those of previous studies that were done in twins and siblings because siblings shared many environmental factors.24
Time Course of Oocyte Pool Depletion It is estimated that the entire process from initiation of follicle growth until complete maturation and finally ovulation takes months.17,18 The majority of follicles will experience atresia by apoptosis at some point in their developmental process.19 Fifty
Table 24-1 Factors Associated with Earlier Onset of Menopause
STAGES OF REPRODUCTIVE AGING
Smoking Genetic factors Family history of early menopause
Until recently there was an absence of a relevant organized nomenclature system for the different stages of female reproductive aging. With this in mind the Stages of Reproductive Aging Workshop (STRAW) was held in Park City, Utah on July 23 and 24, 2001 (Fig. 24-1). As noted in Figure 24-1 the anchor for the staging system is the final menstrual period (FMP). Five stages occur before and two after this anchor point. Stages −5 to −3 cover the reproductive period; stages −2 and −1 are the menopausal transition; and stages +1 and +2 are the postmenopause.
Pelvic surgery Total abdominal hysterectomy Unilateral oophorectomy Metabolic factors Type 1 diabetes mellitus Galactose consumption Galactose-1-phosphate uridyl transferase deficiency Ovulation patterns Nulliparity Shorter menstrual cycles Nonuse of birth control pills
Stages:
-5
Terminology
-4
-3
Reproductive Early
Peak
Late
Final Menstrual Period (FMP) 0 -2 -1 +1 +2 Menopausal Postmenopause Transition Early Late* Early* Late Perimenopause
Menstrual cycles:
Endocrine:
354
variable
variable to regular normal FSH
variable
regular
↑FSH
a 1 yr
variable ≥ 2 skipped variable cycle length cycles and (>7 days an interval of amenorrhea different from normal) (≥60 days)
Amen x 12 mos
Duration of Stage:
until demise
none
↑FSH
↑FSH
*Stages most likely characterized by vasomotor symptoms
b 4 yrs
↑= elevated
Figure 24-1 The STRAW staging system. (From Soules MR: Executive Summary of STRAW, 2001.25–27)
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Chapter 24 Menopause Among the most concrete achievements of STRAW was the development of clear and specific nomenclature, which was previously vague and confusing in the literature. The authors of STRAW recognize that this is a draft and these concepts might evolve as knowledge advances.25-27
Menopausal Transition Stage −2 (early) and −1 (late) encompass the menopausal transition and are defined by menstrual cycle and endocrine changes. The menopausal transition begins with variation in menstrual cycle length in a woman who has a monotropic follicle-stimulating hormone (FSH) rise and ends with the FMP (not able to be recognized until after 12 months of amenorrhea).
Postmenopause Stage +1 (early) and +2 (late) encompass the postmenopause. The early postmenopause is defined as the 5 years after the FMP. The participants agreed this interval is relevant because it encompasses a further dampening of ovarian hormone function to a permanent level as well as accelerated bone loss. Stage +1 was further subdivided into segment a, the first 12 months after the FMP, and segment b, the next 4 years. Stage +2 has a definite beginning but its duration varies, because it ends with death. Further divisions may be warranted as women live longer and more information is accumulated.
during menopause. It is also one of the most puzzling symptoms of menopause, because the etiology and physiology remain incompletely understood.28 It is thought to be the result of a hypothalamic dysregulation from estrogen withdrawal that culminates in peripheral vasodilation and increase in blood flow. This results in heat loss and a decrease in core body temperature. The hypothalamic dysfunction is also manifested by simultaneous pulse of LH and presumably gonadotropin-releasing hormone (GnRH) that is coincident with the hot flash. Hot flash, hot flush, night sweats, and vasomotor symptoms are words frequently used to express the same experience. Hot flashes are defined subjectively as the recurrent transient sensation of heat that can be accompanied by palpitations, perspiration, chills, shivering, and feeling of anxiety. It is then a heat dissipation response that habitually begins in the face, neck, and chest and often becomes generalized.29 Although menopause is the most common cause of hot flashes, other causes should be considered. Fever is by far the most common cause of hot flashes, especially when coupled with a night sweat; thus, if during an episode of hot flashes the oral temperature is elevated the cause of the fever should be sought. In general we can divide the potential causes of hot flashes into seven categories: systemic diseases, neurologic, alcohol– medication interaction, drugs, food additives, eating, and miscellaneous30 (Fig. 24-2). However, is important to emphasize that these other causes are much less common than those associated with hypoestrogenemia.
Perimenopause Perimenopause literally means “about or around the menopause.” It begins with stage −2 and ends 12 months after the FMP. The climacteric is a popular but vague term that we recommend be used synonymously with perimenopause. Generally speaking, the terms perimenopause and climacteric should be used only with patients and in the lay press and not in scientific papers.
CLINICAL SIGNS AND SYMPTOMS OF MENOPAUSE The diagnosis of menopause can be established when the absolute level of serum FSH is elevated. The threshold for the diagnosis of menopause will vary according to the assay employed. In any event, the level will be two standard deviations above the normal value of a reproductive-age woman on cycle day 3. The luteinizing hormone (LH) level is of little value in the evaluation or diagnosis of menopause. The clinical diagnosis of menopause is established retrospectively once a patient has had more than 12 months of amenorrhea in conjunction with vasomotor symptoms such as hot flashes and headaches. At this point the patient has made the transition in the STRAW classification from −1 to +1.The range of symptoms due to immediate estrogen deficiency in women during STRAW stages −1 to +1 includes hot flashes and urogenital changes (see Table 24-1).25–27
Hot Flashes The vasomotor flush is the most characteristic trait of estrogen deficiency. It is experienced at least once in 75% of women
Systemic Diseases
The most common systemic disorders associated with hot flashes are carcinoid syndrome, mastocytosis, pheochromocytoma, medullary thyroid carcinoma, pancreatic carcinoma, and renal cell carcinoma. Carcinoid Syndrome
These are mainly neuroendocrine tumors of the bowel. They may also be found in the bronchus, pancreatic islets, retroperitoneum, liver,31 and even in the ovary.32 They probably arise from gastrointestinal or bronchopulmonary pluripotential stem cells.33 The carcinoid syndrome clinically has a classic triad of diarrhea, flushing, and valvular heart lesions. Skin flushing is the most common sign and is present in more than 90% of patients. The mechanism of flushing is at least partially due to serotonin release, but other substances, such as kinin, substance P, neurotensin, and prostaglandin, may play a role.33 Mastocytosis
Mast cell proliferations can be limited to the skin (cutaneous) or can be spread to extracutaneous tissues (systematic). Vasomotorlike symptoms may be present in these patients because the mast cell granules contain a number of acid hydrolases, leukotrienes, histamine, heparin, and slow-reacting substance.34 Pheochromocytoma
These tumors often arise from the adrenal medulla. Most of their clinical characteristics are due to the production, storage, and secretion of catecholamines. The hallmark sign in these patients is hypertension, which is present in 60% of patients. A significant number of them suffer hot flashes. Documenting increased urinary catecholamines makes the diagnosis.35
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Section 3 Adult Reproductive Endocrinology Figure 24-2 Differential diagnosis of flushing. (Adapted from Mohyi D: Differential diagnosis of hot flashes. Maturitas 27:203–214, 1997.)
Hot Flashes Differential Diagnosis
Systemic diseases
ETOH
Drugs
Neurologic
Carcinoid Syndrome
Metronidazole
Bromocriptine
Anxiety
Mastocytosis
Ketoconazole
Tamoxifen
Migraine
Pheochromocytoma
Chlorpropamide
Nicotinic acid
Parkinson's Disease
Medullary thyroid cancer
Cephalosporins
Opiates
Spinal cord lesions
Panreatic cancer
Calcium blockers
Brain tumors
Renal cell cancer
Cholinergic drugs
Emotional blushing
Food Additives
Eating
Miscellaneous
Monosodium glutamate
Hot beverages
Sodium nitrate
Auriculotemporal flushing
Sulfites
Gustatory flushing Dumping Syndrome
Medullary Carcinoma of the Thyroid
Medullary carcinoma of the thyroid is a malignant tumor that originates from the parafollicular or thyroid C cells. These tumor cells typically produce an early biochemical signal (hypersecretion of calcitonin).36 This cancer can occur sporadically, but many times is inherited in an autosomal dominant way as a part of the syndrome multiple endocrine neoplasia type 2.37 Other bioactive substances that can be secreted by medullary carcinomas and may be responsible for the vasomotor symptoms include corticotropin, corticotropin-releasing hormone, and prostaglandins.30
symptoms when combined with alcohol.38 Others, such as calcium channel blockers, have a direct impact on the vessels.39 On the other hand, tamoxifen or bromocriptine produce hot flashes by triggering different mediators. Vasodilators (nitroglycerin, prostaglandins), calcium channel blockers, nicotinic acid, opiates (i.e., morphine), amyl nitrite, cholinergic drugs, bromocriptine, thyrotropin-releasing hormone, tamoxifen, clomiphene, triamcinolone, and cyclosporine are the most commonly cited medications. Food Additives and Eating Habits
Neurologic Flushing
Anxiety or emotional blushing, migraines, Parkinson’s disease, spinal cord lesions (autonomic hyporeflexia), and brain tumors are associated with hot flashes. Alcohol–Medication Interaction
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Alcohol and numerous drugs are associated with vasomotor symptoms. In some cases the drug is not the real vasoactive agent, but rather a metabolite or another mediator triggered by the drug ingested. Some drugs will only create vasomotor
Monosodium glutamate, sodium nitrite, and sulfites are the most common food additives associated with hot flashes. Hot beverages, auriculotemporal flushing (cheese, chocolate, lemon, highly spicy foods), gustatory flushing (chewing chili pepper), and dumping syndrome (seen in patients after gastric surgery and triggered by a meal, hot fluid, or hypertonic glucose) are examples of symptoms associated with ingesting food or beverage. The main limitation in our ability to assess the value of a treatment for hot flashes is the lack of an objective measure. This complex task is due to the current inability to reliably
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Chapter 24 Menopause identify when a hot flash has taken place. The main objective method used today, sternal skin conductance monitoring, has some limitations, but the main weakness is the failure of sternal skin conductance to provide any information on duration, intensity, and interference with patient activities. Therefore, all data are derived from imperfect methods.28
Morbidity Associated with Hot Flashes Sleep Disturbances
The relationship between hot flashes and interference with sleep is controversial. Multiple epidemiologic studies have shown an association between awakening and arousal from sleep and hot flashes in menopausal women.40–42 This has led to the commonly held conception that hot flashes and night sweats cause awakening, which subsequently creates fatigue, and possibly decreases performance and quality of life.43 The flaw in these studies is that these hypotheses have not been properly tested in controlled laboratory investigations. Also, neither of these investigations screened out patients with apnea and other sleep disturbances that are also prevalent in menopause and may represent a confounder factor. Recently, Freedman and Roehrs studied 31 patients between ages 46 and 51 who were classified into three groups: premenopausal asymptomatic (cycling), postmenopausal asymptomatic (asymptomatic), and postmenopausal symptomatic (symptomatic). They then assessed several outcome measures: sleep electroencephalogram recordings, sternal skin conductance to record hot flashes, multiple sleep latency tests to assess sleepiness, simple and divided attention performance tests, and sleep and fatigue questionnaires. There were no significant differences among the three groups on any sleep variable. Of the awakenings taking place within 2 minutes of a hot flash, 55.2% happened before the hot flash, 40% after the hot flash, and 5% simultaneously. Of arousals taking place within 2 minutes of a hot flash, 46.7% occurred before, 46.7% after, and 5.6% simultaneously. There were no significant group differences on any self-report measure or on any performance measure. They concluded that there is no evidence that hot flashes produce sleep disturbances in symptomatic postmenopausal women.44
Migraines There is sufficient observational data to suggest a link between hormones and migraines.45,46 However, the relationship between menopause and migraine is still being debated. Observational studies suggest that migraine worsens just before menopause and improves after cessation of menses in approximately two thirds of cases. Neri, in a sample of 556 postmenopausal patients, studied the prevalence and characteristics of headaches in this cohort and found that many of them had migraine with aura. Interestingly, women with prior migraine generally improved with the onset of spontaneous menopause. In contrast, women with bilateral oophorectomy usually experienced worsening of their migraines.47 More recently, a cross-sectional, community-based study of 1436 women using the 1988 International Headache Society Criteria showed the highest prevalence of migraines in the perimenopausal group (31%) and the lowest (7%) in the postmenopausal group.48
Urogenital Changes The lack of estrogen has been associated with a decrease in the moisture of the genital tissues. The persistent dryness of the vaginal mucosal surfaces may lead to symptoms of vaginitis, pruritus, dyspareunia, and even stenosis. Other symptoms that may be related to estrogen deprivation in the urogenital tissues are dysuria, urgency incontinence, and urinary frequency. It is unclear whether all these symptoms are related to the lack of estrogen or are part of the degenerative process of aging. It is postulated that changes in estrogen levels change the quality of the collagen content and the connective tissues in the urogenital area.49 More controversial are data suggesting that lack of estrogen increases the likelihood of menopausal women to experience recurrent urinary tract infections (UTIs). A randomized, placebocontrolled trial of vaginal estrogen in 93 postmenopausal women demonstrated that patients being treated could reduce their number of UTIs per year. This study observed 0.5 episodes of UTI in the treatment groups versus 5.9 episodes in the placebo group.50 On the other hand data from the Heart and Estrogen/ Progestin Replacement Study (HERS) showed that urinary tract infection frequency was higher in the group randomized to hormone treatment, although the difference was not statistically significant (odds ratio, 1.16; 95% CI, 0.99–1.37).51 However conflicting these results are, from the clinician’s point of view it seems prudent to attempt a trial of vaginal estrogen therapy to address several of these postmenopausal urogenital symptoms. It should be considered in the presence of a vaginal pH greater than 4.5. Like FSH, elevated vaginal pH appears to be a good predictor of estrogen status.52,53
LONG-TERM MORBIDITY ASSOCIATED WITH POSTMENOPAUSAL STATUS The two major long-term risks associated with menopause are osteoporosis and cardiovascular disease.
Osteoporosis Chapter 25 reviews osteoporosis in detail. In this section we discuss its relationship as a long-term risk factor in menopausal women. The demographic changes and longevity increase described at the beginning of this chapter, coupled with the fact that osteoporosis rises dramatically with age, makes osteoporosis a serious economic burden for healthcare systems in our society.54 The estimated total direct expenditures (hospitals and nursing homes) for osteoporotic and associated fractures was $17 billion in 2001 ($47 million each day).55 The National Osteoporosis Foundation estimates that 50% of white women will suffer at least one osteoporosis-related fracture in their remaining lifetime. At least 90% of hip and spine fractures among elderly women can be attributed to osteoporosis.56 These statistics are the result of an accelerated decline in bone mass after menopause. However, this decline begins at approximately age 35 when a disparity between bone formation and bone resorption begins to occur. After menopause there are two periods of net bone loss: an accelerated stage that begins with the onset of menopause (1 to 3 years) and continues for 5 to 8 years57 (STRAW 0, 1, and 2) and a prolonged, slower stage of bone loss that remains throughout STRAW 2. The initial accelerated phase may account for bone loss of up to 30%.58
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Section 3 Adult Reproductive Endocrinology The three most common osteoporotic related fractures are hip, vertebral, and wrist. The most common are vertebral fractures, accounting for 700,000 cases a year in the United States.55 These should be suspected in postmenopausal women with back pain, loss of height, and kyphosis. In one observational study of 7223 postmenopausal women over age 65, patients with radiographically detected vertebral fractures were found to have significantly more limited-activity days, whether they were symptomatic or not.59 These data should raise awareness for the clinician of the decreased quality of life that menopausal patients may experience even with asymptomatic fractures. The second most common fracture is hip fracture, accounting for 300,000 cases a year in the United States.55 These are without doubt the more serious consequence of osteoporosis in postmenopausal women. One in 5 women will die within 1 year after fracture, and 1 in 2 will have permanent loss of function.60 Lastly, distal forearm fractures occur in 250,000 patients a year in the United States.55 Only half of the patients who suffer these fractures recover full function of the arm in 6 months.61
Cardiovascular Disease
358
The American Heart Association has designated cardiovascular disease a “silent epidemic.” Despite the overall decline in the mortality rate due to cardiovascular disease in the United States, the absolute number of deaths due to cardiovascular disease is actually increasing.62 This is in part due to the demographic changes in our society described in the introduction of this chapter. Cardiovascular disease, which encompasses heart attacks and strokes, is responsible each year for more deaths than all other causes combined in postmenopausal women.62,63 The burden and threat of this disease during menopause is in part due to the discrepancy among the reality of the problem and the perception of its magnitude by both physicians and patients. Nothing exemplifies this better than a 1995 Gallup survey, which revealed that 4 out of 5 women ages 45 to 75 were unaware that cardiovascular disease was the first cause of death for their age group. Instead most of the women quoted cancer, specifically breast cancer, as their most probable cause of death. In reality this represents only 4% of the causes of death in this age group. The primary care physicians questioned did not do very well either; 32% of them did not know that heart disease was the main cause of death in this age group of women.64 The incidence of cardiovascular disease and particularly myocardial infarction dramatically increases after menopause and approximates the mortality of this entity in men.65,66 Furthermore, bilateral oophorectomy or premature ovarian failure increases the risk of cardiovascular disease beyond that of natural menopause.67 Despite this seemingly logical association between estrogen cardioprotection and other coherent data from observational studies, the Women’s Health Initiative (WHI) group of trials and the HERS have found no role for estrogen as a primary or secondary prevention for cardiovascular disease in postmenopausal women. Very sound evidence from epidemiologic studies and clinical research make evident that the best tools are preventive measures and lifestyle habit modifications: smoking cessation, blood pressure control, lowering cholesterol, and promoting exercise.
MEDICAL TREATMENT OF MENOPAUSE The results of the Women’s Health Initiative study (WHI) have altered the principles of medical practice in menopausal women. We have changed from the concept of prevention of chronic diseases encompassed in the term hormone replacement therapy to the concept of hormone therapy. Thus, the U.S. Food and Drug Administration (FDA) and professional organizations such as the American College of Obstetricians and Gynecologists recommend the use of estrogen-containing medications to be restricted to the treatment of vasomotor and vaginal symptoms. They also affirm that the lowest effective dose be prescribed for the shortest duration of time.68–70
Principles of Hormone Therapy During the past three decades the clinical opinion on the use of estrogen during menopause has changed dramatically. Initially, estrogen was recommended as a short-term treatment for menopausal symptoms. Later, on the basis of observational studies, estrogen was given for long-term prevention of heart disease and an improved quality of life. The WHI hormone therapy trial, however, demonstrated that estrogen was not effective for the prevention of cardiovascular disease. Key Findings from the Women’s Health Initiative
The WHI was a group of clinical trials designed to examine the impact of hormone therapy on cardiovascular disease and breast cancer, the effect of low-fat diet on breast and colon cancer, and the impact of vitamin D in calcium supplementation on fractures and colon cancer.71 These trials included: ●
●
●
●
●
A randomized, controlled trial of 16,608 asymptomatic postmenopausal women ages 50 to 79 with a uterus comparing conjugated estrogens (0.625 mg) and a progestin, medroxyprogesterone (2.5 mg), daily versus placebo. The primary outcome measure of this trial was coronary heart disease and breast cancer. The secondary outcome measures were stroke, congestive heart failure, angina, peripheral vascular disease, coronary revascularization, pulmonary embolism, deep venous thrombosis, ovarian cancer, endometrial cancer, hip fractures, diabetes mellitus requiring therapy, death from any cause, and quality of life measures. A randomized, controlled trial on 10,739 asymptomatic postmenopausal women age 50 to 79 without a uterus (hysterectomized) comparing conjugated estrogens (0.625 mg/day) versus placebo. A dietary modification randomized, controlled trial of 48,837 postmenopausal women age 50 to 79 to either sustained lowfat (20%) or self-determined diet. The primary outcome measures were breast and colorectal cancer. The secondary outcome measures included stroke, congestive heart failure, angina, peripheral vascular disease, coronary revascularization, ovarian cancer, endometrial cancer, hip fractures, diabetes mellitus requiring therapy, and death from any cause. A calcium/vitamin D supplementation diet trial of 38,282 postmenopausal women where the primary outcome measure was hip fractures and the secondary outcome measures were death from any cause, breast cancer, and colon cancer. A cohort observation group of 93,676 postmenopausal patients.
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Chapter 24 Menopause Table 24-2 Women’s Health Initiative Findings: Outcomes Associated with Use of Combined Estrogen and Progestin and Estrogen Alone in Healthy Postmenopausal Women, Aged 50 to 79 Years Estrogen and Progestin
Outcome
RR (95% CI)
Estrogen*
Average Absolute Risk Difference†,‡
RR (95% CI)
Average Absolute Risk Difference†
Cardiovascular Deep venous thrombosis Pulmonary embolism Coronary heart disease Ischemic stroke
2.07 2.13 1.24 1.44
(1.49–2.87) (1.39–3.25) (1.00–1.54) (1.09–1.90)
13 8 7 8
1.47 1.34 0.91 1.39
(1.04–2.08) (0.87–2.06) (0.75–1.12) (1.10–1.77)
6 11 −5 12
Cancer Breast Colorectal Ovarian Endometrial
1.24 0.63 1.58 0.81
(1.02–1.50) (0.43–0.92) (0.77–3.24) (0.48–1.36)
8 −6 8 −4
0.77 (0.59–1.01) 1.08 (0.75–1.55) NYR N/A
−7 1 NYR N/A
Other Probable dementia§ All fractures Hip fractures
2.05 (1.21–3.48) 0.76 (0.69–0.83) 0.67 (0.47–0.96)
23 −44 −5
NYR 0.70 (0.63–0.79) 0.61 (0.41–0.91)
12 −56 −6
Mortality
0.98 (0.82–1.18)
−1
1.04 (0.88–1.22)
+3
Abbreviations: RR, relative risk compared to placebo; CI, confidence interval; N/A, not applicable (hysterectomized women); NYR, not yet reported. *Hysterectomized †Annual per 10,000 women ‡Compared to placebo group §Women aged 65 to 79
In May 2002 the clinical trial that aimed to assess the cardiovascular effects of estrogen and progestin therapy in postmenopausal women with intact uterus was halted. The Data and Safety Monitoring Board reported that the estrogen/progestin treatment group had an increased risk of cardiovascular disease, thromboembolism, and breast cancer after 5.2 years of followup.72 In 2004, after 6.8 years of follow-up, the estrogen-only trial was halted.73 In this clinical trial, estrogen-only treatment demonstrated an increase risk of strokes similar to the one found in the estrogen/progestin clinical trial previously halted. They also reported a lack of benefit on cardiovascular disease incidents and a probable increase in dementia. The risks and benefits findings of the WHI are summarized in Table 24-2.74 The WHI findings should not be generalized to the whole menopausal population, but rather to the population studied and the specific treatment used in the trial. Some researchers argue that there might be a difference in the thromboembolic risk among the different estrogen compositions. It should be emphasized that the WHI trial did not intend to evaluate the effects of estrogen or estrogen/progestin on vasomotor symptoms; therefore, these results must be translated into the specific needs of our patients when they request relief for hot flashes or other postmenopausal symptoms. It is also critical to point out that the rate of serious adverse events in patients treated with estrogen therapy is low, calculated to be 2 out of 1000 women treated per year.75 Healthcare providers and patients must balance the benefits of estrogen treatment versus the risk for adverse events. Today, more than ever, the concept of individualized menopausal care should be applied in the clinical setting. The WHI hormone trial is the first randomized, controlled trial that demonstrates that estrogen actually decreases the risk of fractures in a low-risk population. However, when all the
risks and benefits are weighted, it can be concluded in this study that estrogens are not indicated as a preventive measure in postmenopausal women and the potential harm outweighs the potential benefit. Thus, at the present time, use of estrogen should be limited to the treatment of symptomatic menopausal women for the shortest possible time at the lowest dose. Key Findings of the Heart and Estrogen/Progestin Replacement Study
Whereas the WHI aimed to test the hypothesis that hormone therapy prevented cardiovascular disease in healthy postmenopausal women (primary prevention), the Heart and Estrogen/ Progestin Replacement Study (HERS) intended to evaluate whether hormone therapy decreased the risk of coronary heart disease in postmenopausal women with established coronary disease. In this randomized trial, all the 2763 postmenopausal women had uterus and were allocated to either placebo (n = 1383) or 0.625 mg of conjugated equine estrogens plus 2.5 mg of medroxyprogesterone acetate daily (n = 1380).76,77 The primary outcome measures were nonfatal myocardial infarction and death from coronary heart disease. The results of the HERS trial have been reported in two publications: HERS and HERS II. The HERS report is the result of randomized, blinded, placebo-controlled trial for 4.1 years; the HERS II reflects the unblinded follow-up for 2.7 more years.76,77 Both of the studies demonstrated that in patients with established heart disease, the use of estrogen and progestin does not prevent additional cardiovascular events. There were no differences in the primary or secondary outcomes of patients in the placebo or the treatment group. The conclusion of HERS and HERS II is that postmenopausal hormone therapy should not be recommended for the purpose of reducing the risk of cardiovascular events. Table 24-3 shows a comparison between the WHI and HERS trials.
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Section 3 Adult Reproductive Endocrinology Table 24-3 Comparison of Findings of the Women’s Health Initiative Study (WHI) and the Heart and Estrogen/Progestin Replacement Study (HERS) WHI-Cardiac Heart Disease by Year of Follow-Up
HERS-Risk of Cardiac Events
Estrogen-Progestin (n=8000)
Placebo
Hazard Ratio & Confidence Interval
Estrogen-Progestin (n=1383)
Placebo (n=1380)
Relative Hazard (Risk) & Confidence Interval
1
42 cases
23 cases
1.81 (1.09–3.01)
57 cases
38 cases
1.52 (1.01–2.29)
2
38
3
19
28
1.34 (0.82–2.18)
47
48
1.00 (0.67–1.49)
15
1.27 (0.64–2.50)
35
41
4
0.87 (0.55–1.37)
32
25
1.25 (0.74–2.12)
33
49
0.67 (0.43–1.04)
5
29
19
1.45 (0.81–2.59)
1.06 (0.69–1.62)
>6
28
37
0.70 (0.42–1.14)
0.98 (0.72–1.34)
Year
Table 24-4 Incidence of Invasive Breast Cancer in Relation to Recency of Use of Hormone Replacement Therapy HRT Use at Baseline
Cases/Population
Never users
2894/392,757
Current users
Relative Risk (95% FCI)* 1.00 (0.97–1.04)
3202/285,987
1.66 (1.60–1.72)
Last use <5 years previously
579/81,875
1.04 (0.95–1.12)
Last use 5–9 years previously
207/29,395
1.01 (0.88–1.16)
Last use ≥10 years previously
79/12,568
0.90 (0.72–1.12)
χ2 for heterogeneity between ever users = 161.5, p < 0.0001
0.5
1.0
1.5
2.0
FCI=floated Cl. *Relative to never users, stratified by age, time since menopause, parity and age at first birth, family history of breast cancer, body-mass index, region, and deprivation index. From Beral V, for the Million Women Study Collaborators: Breast cancer and hormone-replacement therapy in the Million Women Study. Lancet. 362(9382):419–427, 2003.
Key Findings of the Million Women Study
The Million Women Study is a prospective cohort study, which included 1,084,110 British women age 50 to 64 recruited between 1996 and 2001. This study was undertaken by the UK National Health Service Breast Screening Programme, targeting women age 50 to 64 undergoing routine screening once every 3 years. Because only approximately half of these patients had ever taken estrogen after menopause, the aim of the study was to investigate the relation between various combinations of hormone therapy and two main outcomes: breast cancer and mortality.78 All patients filled out a questionnaire and were monitored in this manner. This questionnaire is available at http://www.millionwomenstudy.org. A major strength of this study was the unparalleled database size, which was sufficiently powered to quantify absolute and relative risks and enabled researchers to discern the effects among different preparations of hormones in use among postmenopausal women. One weakness of the study was that hormone use versus nonuse was determined on admission to the study and was not modified during follow-up even though there were potential multiple crossover treatments in some of the subjects. The authors reached these conclusions: ●
360
●
Current use of hormone therapy is associated with an increased risk of incident and lethal breast cancer. The risk is substantially greater for estrogen/progestin combinations of postmenopausal hormone therapy.
●
The mortality rate due to breast cancer was 27% less in hormone users than in nonhormone users. This is perhaps due to more frequent medical care and early detection.
The relative risks for invasive breast cancer in relation to current of use of hormone therapy and type of hormone preparations are illustrated in Tables 24-4 and 24-5.
Candidates for Hormone Therapy during Menopause It is clear that the paradigm has shifted when it comes to who should use estrogens during menopause. After reviewing the evidence in the randomized, controlled trials it seems prudent to state that estrogen should not be used to prevent long-term chronic diseases such as cardiovascular disease and dementia. Nevertheless, patients with moderate to severe vasomotor symptoms should weigh the risk and benefits and might consider using estrogen. It seems that the group of patients with vasomotor symptoms and osteoporosis or at risk for osteoporosis are good candidates to consider prescribing estrogen. Estrogen is the bestproven method to alleviate vasomotor symptoms and has been shown to reduce the fracture risk in postmenopausal women. The medical management of menopausal symptoms has evolved to a personalized approach. Personal choice is important, and some will never take hormone therapy under any circumstances. The physician must consider many variables before offering hormone therapy, such as personal, cardiovascular,
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Chapter 24 Menopause Table 24-5 Incidence of Invasive Breast Cancer in Relation to Recency and Type of Hormone Replacement Therapy HRT Use at Baseline
Cases/Population
All never users
2894/392,757
1.00 (0.96–1.04)
Relative Risk (95% FCI)*
All past users
1044/150,179
1.01 (0.95–1.08)
Current users of: Estrogen only Estrogen-progestin Tibolone Other/unknown types
991/115,383 1934/142,870 184/18,186 93/9548
1.30 2.00 1.45 1.44
(1.22–1.38) (1.91–2.09) (1.25–1.67) (1.17–1.76) 0.5
1.0
1.5
2.0
2.5
FCI=floated Cl. *Relative to never users, stratified by age, time since menopause, parity and age at first birth, family history of breast cancer, body-mass index, region, and deprivation index. From Beral V, for the Million Women Study Collaborators: Breast cancer and hormone-replacement therapy in the Million Women Study. Lancet. 362(9382):419–427, 2003.
osteoporosis, breast cancer risk, the number and severity of estrogen-deficient symptoms.
General Principles of Drug Therapy When patients are receiving hormone replacement therapy, there are two important concepts that must be discussed. First, how long will the patient be on medication? All groups interested in the medical management of the menopause suggest that the lowest effective dose be utilized for the shortest duration consistent with the treatment goals. If it is for the treatment of vasomotor symptoms, it could be for a limited period. If it is for the treatment of osteoporosis, it could be for a longer period. Secondly, how will the effectiveness of therapy be measured? Typically this consists of assessing symptoms and signs of hypoestrogenemia and monitoring bone mineral density. The choice of drug regimen should be based on the specific need of the patient. For example, a breast cancer patient with severe genitourinary atrophy who has failed nonhormonal regimens may benefit from a locally applied medication that has little systemic absorption. Hot flashes can be controlled with continuous estrogens rather than cyclic. If the hot flashes are not controlled, a progestin can be added if this has not already been used. Increased metabolism of estrogen by concomitant use of antiseizure drugs should be considered and substitution with a transdermal form with less hepatic metabolism should be tried. Patients who do not or cannot use estrogens can be offered a selective serotonin reuptake inhibitor. All patients with a uterus should be given a progestin. The progestin can be given cyclically, such as the first 12 to 14 days of each month, or continuously (daily). The majority of patients on cyclic therapy will have a monthly withdrawal bleed. The continuous regimen will induce irregular bleeding initially but will eventually result in amenorrhea. Patients with a uterus require endometrial monitoring to detect possible hyperplasia or cancer. With cyclic regimens, bleeding occurs after 6 days of progestin therapy. Unscheduled bleeding or a change in the pattern of bleeding requires investigation. A transvaginal ultrasound should be performed. If the endometrial thickness is less than 5 mm, endometrial cancer is ruled out. If the endometrial thickness is 5 mm or greater, an endometrial sampling should be
performed. If the thickness is less than 5 mm but bleeding persists or recurs, then a sampling should also be performed. Absolute contraindications to estrogens include acute venous thrombosis, embolism, and cardiovascular or liver disease. Untreated endocrine-sensitive tumors and undiagnosed vaginal bleeding are also contraindications. Relative contraindications include the chronic forms of the previous mentioned conditions as well as uncontrolled hypertension and hypertriglyceridemia. Some traditional relative contraindications, such as seizure disorders, migraines, gallbladder disease, and myomas, are a matter of debate. Patients with a personal or family history of venous thromboembolism should be screened for a possible thrombophilia before starting hormone replacement therapy.
Hormone Preparations for Menopausal Therapy As has been reviewed, use of hormone therapy has some documented increased risks, including stroke, breast cancer, coronary heart disease, and venous thromboembolism. Nevertheless, this does not mean that postmenopausal hormone therapy must never be used. Postmenopausal women with severe vasomotor symptoms, vaginal dryness, and/or other symptoms that decrease the quality of life continue to be appropriate candidates for hormone therapy in the absence of contraindications, such as a history of coronary artery disease, thrombophilia, and thromboembolism. Recently the concept of bioidentical has been used by the public and some practitioners. This refers to use of steroids that are found in humans and sometimes to the concept of individualizing the doses by specifically compounding a product. There are no data to support the superiority of this approach.
Systemic Estrogen Therapy Systemic absorption can occur with oral, transdermal, or vaginal preparations. All estrogens are metabolized in the liver, but the oral forms will have a dominant first-pass effect that is manifested by elevated binding globulins, triglycerides, and clotting factors. Estrogen therapy may increase thyroxine requirements. Oral Estrogen
Several oral preparations of estrogen are available, the most commonly used being Premarin (Table 24-6). This compound of
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Section 3 Adult Reproductive Endocrinology Table 24-6 Estrogen Products, Routes of Administration, and Available Doses
Product
Available Doses Oral
Synthetic conjugated estrogens (Cenestin, Enjuvia)
0.3 mg, 0.45 mg, 0.625 mg, 1.25 mg
Equine conjugated estrogens (Premarin)
0.3 mg, 0.45 mg, 0.625 mg, 0.9 mg, 1.25 mg, 2.5 mg
Micronized estradiol (Estrace, Gynodiol)
0.5 mg, 1.0 mg, 2 mg
Esterified estrogens (Menest)
0.3 mg, 0.625 mg, 1.25 mg, 2.5 mg
Estropipate (Ogen, Ortho-Est)
0.625 mg, 1.25 mg, 2.5 mg Transdermal Systems
17-β estradiol (Estraderm, Vivelle, Alora, Climara, Esclim, Menostar) 17-β estradiol plus norethindrone acetate or levonorgestrel (Combipatch, Climara Pro)
0.025 mg, 0.0375 mg, 0.05 mg, 0.075 mg–0.1 mg/day 14 μg/day 0.045–0.05 mg/day plus 0.14 mg/day, 0.15 mg/day, 0.25 mg/day
Topical 17-β estradiol (Estrasorb, Estrogel)
3.48 g/day delivers 0.5 mg/estradiol/day 1.25 g/day delivers 0.75 mg/estradiol/day Injectable
Estradiol valerate in oil (Delestrogen)
10 mg/ml–40 mg/ml
Estradiol cypionate in oil (Depo-Estradiol)
5 mg/ml Vaginal
Tablets (Vagifem)
25 μg estradiol/tablet
Creams Estrace Premarin Ogen
0.1 mg ethinyl estradiol/g 0.625 conjugated equine estrogen mg/g 1.5 mg estropipate/g
Rings Estring Femring
362
Estradiol 2 mg/3 months/ring (7.5 μg/day) Estradiol 0.05 mg–0.1 mg/day for 90 days (systemic absorption)
conjugated equine estrogens derived from pregnant mare’s urine consists mostly of estrone sulfate, equilin sulfate, dihydroequilin sulfate, and many other minor estrogens. There are also conjugated synthetic estrogens such as Cenestin that are derived from plant sources. Esterified estrogens, such as Estratab or Menest, are derived from plant sources as well. Ethinyl estradiol is found in oral contraceptives but also in one product for hormone therapy called FemHRT. Estrace is a micronized form of estradiol. Although there are different dosages and potencies of estrogens, there is no difference in their efficacy.79 Due to the concerns about cardiovascular disease and thromboembolism with the use of estrogen therapy, new low-dose regimens have been approved by the FDA for treatment of vasomotor symptoms and osteoporosis: Prempro in dosage strengths of 0.45 mg conjugated estrogen/1.5 mg medroxyprogesterone acetate and 0.3 mg conjugated estrogen/1.5 mg medroxyprogesterone acetate. The HOPE trial showed no evidence of endometrial hyperplasia in women treated with
conjugated equine estrogens/medroxyprogesterone acetate regardless of the dose.80 These clinical trials have also demonstrated that low doses of estrogen are adequate for the prevention of bone loss. Transdermal Estrogen
All transdermal systems currently available contain the same estrogen, 17β-estradiol, in different dosages. A dose of 50 μg/day in a transdermal delivery system is bioequivalent to an oral dose of 0.625 μg of conjugated equine estrogens.81 The lowest-dose transdermal delivery system approved for prevention of osteoporosis (Menostar) has only 0.014 mg/day of estradiol.82 Topical Estrogen
The products available are Estrogel and Estrasorb. A randomized, controlled trial of 225 menopausal women demonstrated that a topical gel containing 1.25 or 2.5 g was much more effective than placebo in alleviating the frequency and intensity of moderate and severe hot flashes in symptomatic women.83 Vaginal Estrogen
When the target organ of the hormonal preparation is the urogenital tissue, the vaginal route of administration seems to be the most appropriate way to provide relief to symptomatic postmenopausal women. The safety and efficacy of vaginal delivery has been widely studied and there are cream, tablet, and ring preparations available in the market. The Estring vaginal ring delivers local estradiol without significant estrogen absorption. It is placed for 3 months. Other intravaginal products such as Femring can have systemic absorption, which necessitates consideration of an endometrial effect. There are some general rules of equivalence between these products. Ethinyl estradiol 5 μg, 0.625 mg of conjugated or esterified estrogens, 1 mg of mirconized estradiol, and 0.05 mg of a transdermal estradiol are considered equivalent.
Selective Estrogen Receptor Modulators The usefulness of alternative medications to treat or prevent chronic diseases such as osteoporosis has been increasing. The mixed estrogen agonist-antagonist action that selective estrogen receptor modulators (SERMs) demonstrated in specific target tissues such as bone and their binding with estrogen receptors makes them a good option for some patients.84 There are many reasons why SERMs produce their tissue-selective effects, such as differences in receptor binding affinities and interaction with different coactivators and corepressors.85 Tamoxifen
Tamoxifen is a SERM that may act as an estrogen receptor agonist (i.e., uterus) or as an antagonist (i.e., breast).86 As a result tamoxifen can have beneficial effects in osteoporosis, breast cancer, and cardiovascular disease. Tamoxifen also stimulates endometrial proliferation and increases vasomotor symptoms. In the largest randomized clinical trial aimed to test the hypothesis that tamoxifen reduces the incidence of breast cancer in patients at high risk for the disease, fracture risk was determined as a secondary endpoint. In The National Surgical Adjuvant Breast and Bowel Project (NSABP) P-1 Trial, 13,338 women were randomized to placebo or 20 mg of tamoxifen a day for
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Chapter 24 Menopause 5 years. The trial demonstrated a significant decrease in the incidence of invasive and noninvasive breast cancer, and a decrease in the incidence of vertebral, wrist (Colles’), and hip fractures in the treatment group when compared with the placebo. In this same study, patients in the tamoxifen group did not experience a higher rate of ischemic heart disease. However, the risk for endometrial cancer, especially in women over age 50, was increased (RR, 2.53; 95% CI, 1.35–4.97), with all of the endometrial cancers detected in early stage (I).87
Raloxifene studies have also shown improvement in some intermediate cardiovascular outcome measures, such as serum low-density lipoprotein, lipoprotein (a), homocysteine, and plasma fibrinogen.95,96 To test the hypothesis that raloxifene reduces risk of coronary events (coronary death, nonfatal myocardial infarction, or hospitalized acute coronary syndromes other than myocardial infarction) the Raloxifene Use for The Heart (RUTH) trial was begun in 1998.97 Tibolone
Raloxifene
Raloxifene was discovered over 20 years ago in an effort to develop an antiestrogenic drug to treat and/or prevent breast cancer and was previously known as keoxifene.88,89 Raloxifene, like other SERMs, seems to compete with endogenous estrogens for attaching to the cytoplasmic receptor and may either turn on or turn off estrogen-mediated transcription. The complete molecular mechanism by which estrogens and SERMs exercise their biologic actions on various tissues has not been entirely understood and still is an area of intensive investigation. Raloxifene reduced the risk of osteoporosis in postmenopausal women without increasing their risk for uterine cancer or endometrial hyperplasia.90,91 Raloxifene at 60 mg/day is currently approved for the prevention and treatment of osteoporosis. Some clinicians prefer to use biphosphonates as a first option because of their more potent antiresorptive activity compared to raloxifene.92 A comparative trial compared the two classes of drugs. In the EFFECT trial (EFficacy of Fosamax versus Evista Comparison Trial), patients in the alendronate group were found to have substantially greater increases in bone mineral density (BMD) than those in the raloxifene group at both lumbar spine and hip sites at 12 months. Lumbar spine BMD increased 4.8% with alendronate versus 2.2% with raloxifene (P < 0.001). The increase in total hip BMD was 2.3% with alendronate versus 0.8% with raloxifene (P < 0.001). Decreased bone turnover was more significant with alendronate than raloxifene. Overall tolerability was comparable. However, the number of patients reporting vasomotor symptoms was considerably higher with raloxifene (9.5%) than with alendronate (3.7%, P = 0.010); an equal number of patients reported adverse gastrointestinal side effects.91 Besides the positive impact in intermediate outcome measures such as BMD and bone markers, raloxifene has been proven to reduce the risk of osteoporotic vertebral fractures. In the MORE trial (Multiple Outcomes of Raloxifene Evaluation) a multicenter, international, double-blind, placebo-controlled trial, 7705 women age 31 to 80 years in 25 countries who had been postmenopausal for at least 2 years were randomized to one of three groups: 60 mg/day of raloxifene, 120 mg/day of raloxifene, or placebo. After 36 months of follow-up the risk of vertebral fracture was reduced in both study groups receiving raloxifene (for 60-mg/d group: relative risk [RR], 0.7; 95% CI, 0.5–0.8; for 120-mg/d group: RR, 0.5; 95% CI, 0.4–0.7).93 This study also demonstrated that breast cancer was less common in the treatment arms than in the placebo arm. Thirteen cases of breast cancer were confirmed among the women assigned to raloxifene versus 27 among the women assigned to placebo (RR, 0.24; 95% CI, 0.13–0.44; P<.001).94 A follow-up STAR trial (Study of Tamoxifen And Raloxifene) will compare raloxifene and tamoxifen for the prevention of breast cancer.
Tibolone is a synthetic steroid that has been shown to be effective in alleviating menopausal symptoms and preventing bone loss. It has been widely used in Europe and the rest of the world since 1988. Clinical trials are under way in the United States. Tibolone has estrogenic actions in the brain, vagina, and bone tissues, but lacks estrogenic activity in the endometrium and in breast tissue. Its multifaceted hormone properties may stem from the fact that tibolone is quickly biotransformed into three metabolites: 3α- and 3β-hydroxy-tibolone, each with estrogenic effects, and the Δ4-isomer, with progestogenic and androgenic effects. The tissue-selective actions of tibolone are the product of metabolism, enzyme control, and receptor activation that vary in responsive target tissues. This biotransformation takes places principally at the liver and intestine. These pharmacologic characteristics make tibolone unique and different from the typical SERMs.98 More recently, an even lower dose of tibolone was evaluated in a randomized clinical trial. This study included 90 postmenopausal women who were followed for 2 years and were allocated to tibolone 2.5 mg (n = 30), tibolone 1.25 mg (n = 30), and a control group (n = 30). All subjects received 1000 mg of calcium per day. Gambacciani and colleagues demonstrated tibolone to be effective at lower doses, not only at preventing bone loss as measured by BMD, but also at alleviating vasomotor symptoms.99 Another interesting potential benefit of tibolone in postmenopausal women is the positive effect shown on libido in some clinical trials. In a small randomized trial, patients with postmenopausal changes in sexual desire were allocated to 2.5 mg/day of tibolone (n = 14) or to 500 mg/day of calcium. This trial showed that the patients treated with tibolone experienced an improvement in sexual desire after the third month of treatment, which was maintained until the end of treatment (12 months).100 Similar beneficial findings in sexual desire were shown in a small study of 50 postmenopausal patients who were treated with either tibolone or conjugated estrogens and medroxyprogesterone.101 In the large cohort Million Women Study, there was increased relative risk of breast cancer in current users of tibolone (RR, 1.45; 95% CI, 1.25–1.68).78 These results were not anticipated, because tibolone does not increase breast density and has been shown to have much less estrogenic activity in breast tissues than other agents in postmenopausal clinical trials.102,103 In summary, clinical data supports the use of tibolone as a viable option for hormone therapy during menopause. Its versatile actions in different target tissues have demonstrated beneficial effects for the relief of vasomotor symptoms and treatment of osteoporosis. There is evidence to suggest that tibolone may positively impact libido in postmenopausal women. Unfortunately, there are few randomized trials, and a lack of long-term clinical evidence of tibolone benefits on the cardiovascular and neurologic systems.
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Section 3 Adult Reproductive Endocrinology Table 24-7 Randomized Controlled Trials of Selective Serotonin Reuptake Inhibitors (SSRIs) for the Treatment of Vasomotor Symptoms in Postmenopausal Women SSRI/groups
Subjects
Venlafaxine (2000)* Placebo 37.5 mg/day 75 mg/day 150 mg/day
191 50 49 43 49
Venlafaxine (2005)† Placebo 37.5 mg/d x 1 week then 75 mg/d x 11 weeks Paroxetine (2003)‡ Placebo 12.5 mg/day 25 mg day
61 32 29 165 56 51 58
Fluoxetine (2002)§ Placebo/fluoxetine 20 mg Fluoxetine 20 mg/placebo
81 41 40
Endpoint
Length of the Study
Comments
Reduction average daily hot flushes 27% 37% 61% 61%
4 weeks
Side effects: nausea, dry mouth, constipation, decreased appetite
Reduction patient perceived hot flush score 15%
12 weeks
Side effects: dry mouth, sleeplessness, decreased appetite
Mean change daily hot flash composite score 37.8% 62.2% 64.6%
6 weeks
Clinical global impression also improved significantly in treatment groups
Hot flash frequency and hot flash score 36% 50%
1 week documentaton 4 weeks each period Total of 9 weeks
Randomized crossover trial Well tolerability of fluoxetine
Other benefits: decreased depression scores, improved quality of life scores
51%
*Lancet. 2000 Dec 16;356(9247):2059–63 † Obstet Gynecol. 2005 Jan;105(1):161–6. ‡ JAMA. 2003 Jun 4;289(21):2827–34. §
J Clin Oncol. 2002 Mar 15;20(6):1578–83.
Androgens The use of androgens for postmenopausal women is the subject of much debate. The concept of sexuality in women is complex and not directly related to serum androgens. Nonetheless many clinical trials have assessed the use of testosterone. Results are conflicting, and currently there are no FDA-approved testosterone replacements for women.
Progestins Oral progestins that are typically used are medroxyprogesterone acetate, micronized progesterone (Prometrium), and norethindrone. These hormones can be used cyclically or continuously. Medroxyprogesterone acetate 5 to 10 mg or micronized progesterone 200 mg can be given for the first 12 days of each month. Lower doses are used for continuous use. Typical doses for this are 2.5 mg medroxyprogesterone acetate (Prempro), 1 mg norethindrone (FemHRT), or 100 mg micronized progesterone. Some progestins are formulated with the estrogen, such as Prempro, which contains medroxyprogesterone acetate or FemHRT, which containes norethindrone 0.5 to 1 mg. A low-dose levonorgestrel intrauterine device is under investigation as a method of endometrial protection.
Selective Serotonin Reuptake Inhibitors
It is clear that estrogen is the most effective and studied medication to treat vasomotor symptoms. However, given the results of the WHI, more patients and physicians are considering nonestrogen methods for treatment of vasomotor symptoms.
Th SSRIs (Table 24-7) seem to effectively decrease vasomotor instability in menopausal women by increasing the availability of serotonin in the central nervous system. These compounds should be considered a possible option to control hot flashes in women not willing to take estrogen or in whom estrogen is contraindicated. There are several open-label trials and enough randomized, controlled trials to currently recommend them as a reasonable option. There are studies evaluating citaprolam, paroxetine, and sertraline. Perhaps the most widely studied and used agent is venlafaxine, which is not strictly an SSRI because it inhibits both serotonin and norepinephrine reuptake.
Clonidine
Gabapentin
Clonidine is an antihypertensive medication that acts centrally as an α2-adrenergic agonist and can be administered orally or via a transdermal delivery system. Clonidine has been used to treat hot flashes in postmenopausal women and in postorchiectomized
Gabapentin is a γ-aminobutyric acid analogue approved in 1994 for the treatment of seizures and has been used by neurologists to treat neuropathic pain, essential tremor, and migraines.106 In a randomized, double-blind, controlled trial that included 59
Nonhormonal Therapies
364
men.104 The evidence to support its use is limited. One controlled trial randomized 15 patients to placebo and 14 to transdermal clonidine. Subjects were followed for 8 weeks; 86% of the patients in the treatment group had a significant decrease in the frequency of vasomotor episodes, 73% had a decrease in the severity of flushes, and 67% saw a decrease in the duration of hot flushes. In the placebo groups these benefits were present in 36%, 29%, and 21%, respectively.105 One characteristic consistent throughout the retrospective and prospective clinical trials of clonidine was the high percentage of patients with side effects. Dry mouth was experienced in up to 40% of patients, drowsiness and dizziness in up to 35%, and skin rash and irritation in 15% of oral and up to 50% in the transdermal system. If no other treatment fits the need of the symptomatic postmenopausal patient, clonidine can be tried in a dose of 2.5 mg of a transdermal system changed every week. Clonidine also may be prescribed divided orally in doses of 0.1 to 0.4 mg/day.
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Chapter 24 Menopause menopausal women with 7 or more severe hot flashes a day, a dose of 900 mg/day of gabapentin was given for 12 weeks. Gabapentin was associated with a 45% reduction in hot flash frequency and a 54% reduction in hot flash composite score (frequency and severity combined into one score) from baseline, compared with 29% (P = 0.02) and 31% (P = 0.01) reductions, respectively, for placebo.107 One out of five patients taking gabapentin will experience dizziness and somnolence. Thus, this very expensive compound has minimal efficacy and is not an effective option for treatment of vasomotor flushes.
● ● ●
●
●
●
Veralipride
Veralipride is a neuroleptic antidopaminergic with antigonadotropic activity that is extensively used in Latin America and Europe for the treatment of vasomotor symptoms. This medication is currently not available in the United States. In a short 20-day, double-blind, randomized trial that included 43 symptomatic postmenopausal women, 21 subjects received 100 mg/day veralipride and 22 received 1.25 mg/day of conjugated estrogens. Individuals taking veralipride had a significant improvement comparable to estrogen. Tolerance was adequate in both groups.108 These findings have been confirmed in another pilot trial.109 Veralipride has also shown to be useful in treating the hot flashes caused by raloxifene. In fact a study demonstrated that giving raloxifene 60 mg/day continuously and veralipride 100 mg every other day eliminated the complaints of vasomotor symptoms in patients taking this SERM.110
DIETARY AND LIFESTYLE RECOMMENDATIONS DURING MENOPAUSE There is little doubt that prevention is the best strategy to live a healthy life. As healthcare providers, we should regard the onset of menopause as a signal for the future living rather than visualizing it as the decline of a woman’s life. This phase is a great window of opportunity for healthcare providers to help the patient establish dietary and lifestyle habits to maximize her physical, social, mental, and sexual opportunities. It can be a bright new beginning.
Calcium Recommendations One of the key elements to preventing osteoporosis is maintaining a positive calcium balance. This task becomes challenging during menopause because calcium absorption declines with age. Furthermore, the lower levels of estrogen during menopause decrease the levels of 1,25-dihydroxyvitamin D, with the subsequent consequence of even less calcium absorption.111 Nordin and coworkers measured radiocalcium absorption in 262 postmenopausal women age 40 to 87 and demonstrated a late age-related decrease (only after age 75) in calcium absorption in postmenopausal women in addition to the decline that occurs at menopause. They concluded that this decrease could be due to a decline in either the active calcium transport or the diffusion component of the calcium absorption system.112 According to the National Institutes of Health Consensus Development Conference on Optimal Calcium Intake held on 6–8 June 1994, the following are the calcium intake recommendations in women:113 ●
1200–1500 mg/day for adolescents and young adults (age 11–24)
●
●
1000 mg/day for women between age 25 and 50 1200–1500 mg/day for pregnant or lactating women 1000 mg/day for postmenopausal women on estrogen replacement therapy 1500 mg/day for postmenopausal women not on estrogen therapy. For all women over 65, daily intake of 1500 mg/day, although further research is needed Adequate vitamin D is essential for optimal calcium absorption. Dietary supplements, hormones, drugs, age, sun exposure and genetic factors influence the amount of calcium required for optimal skeletal health. Calcium intake up to 2000 mg/day, appears to be safe in most individuals The preferred source of calcium is calcium-rich foods such as dairy products, but calcium-fortified foods and calcium supplements are other means by which optimal calcium intake can be reached in those who cannot meet this need by ingesting conventional foods.
These guidelines are based on calcium from the diet plus any calcium taken in supplemental form and all are based on elemental calcium. The preferred method of reaching optimal calcium intake is through dietary sources. Among the foods with higher content of calcium are dairy products, green vegetables (e.g., broccoli, kale, turnip greens, Chinese cabbage), calcium-set tofu, some legumes, canned fish, seeds, nuts, and certain fortified food products, like bread and cereal. A good rule of thumb to calculate the daily intake of calcium is to multiply the number of milk servings (8 oz = 240 mL = 1 cup) by 300 mg.115 There are tables available that can be used to estimate the daily intake of calcium in a patient’s diet.114 Due to the challenges of achieving adequate calcium intake via food sources, many physicians advocate the use of calcium supplements. There are two main types of calcium compounds available in the market: calcium carbonate and calcium citrate. Some authors advocate the use of calcium citrate (Citracal) over calcium carbonate (Os-Cal), arguing that calcium citrate is better absorbed, especially on an empty stomach.115,116 On the other hand, calcium carbonate is usually less expensive and according to at least one study of absorbability, bioavailability, and costeffectiveness the carbonate formulation is a better supplement choice in a population at risk for both low BMD and hip fracture.117
Vitamin D Vitamin D is not usually found in food. It is produced by the skin in response to light exposure. There is controversy regarding the right amount of oral intake of vitamin D that is required. The Recommended Dietary Allowance (RDA) in women age 51 or older is 400 IU (10 μg/day) and is based on the dose needed to prevent rickets.118,119 A dose of 800 IU should be considered for those living in Northern climates.
Exercise Many health-related exercise recommendations are based on studies done in men. However, a recent systematic review of all the randomized, controlled exercise trials in postmenopausal
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Section 3 Adult Reproductive Endocrinology women delineates some benefits in intermediate outcome measures. In a systematic review, Asikainen and colleagues assessed 28 randomized, controlled trials with 2646 subjects. Based on this review of studies on postmenopausal women, they describe specific guidelines for health professionals to use when counseling their patient to adequately develop an exercise program.120 ●
●
●
●
●
Early postmenopausal women could benefit from 30 minutes of daily moderate walking in one to three episodes combined with a resistance-training program twice a week. For a sedentary person, walking is a feasible way to start exercise by incorporating it into everyday life. A feasible way to start resistance training is to perform 8 to 10 repetitions of 8 to 10 exercises for major muscle groups starting with 40% of one repetition maximum. Resistance training initially requires professional instruction, but can thereafter be performed at home with little or no equipment as an alternative to a gym with weight machines. Warm-up and cool-down with stretching should be a part of every exercise session.
The training described probably will preserve normal body weight. When combined with a weight-reducing diet, exercise will likely reduce bone loss and increase muscle strength. Based on limited evidence, such exercise might also improve flexibility, balance, and coordination; decrease hypertension; and improve dyslipidemia.120
effective for treatment of menopausal symptoms.124 These products are used by as many as 46% to 79% of menopausal patients in some surveys.125,126 A review of randomized, controlled trials of complementary and alternative medicine for the treatment of menopausal symptoms by Kronenberg and colleagues evaluated a total of 29 randomized, controlled trials of complementary and alternative therapies for hot flashes and other menopausal symptoms; of these, 12 dealt with soy or soy extracts, 10 with herbs, and 7 with other therapies. They concluded that although soy products seem to have modest benefit for hot flashes, studies are not definitive. Isoflavone preparations seem to be even less effective than soy products. Black cohosh may be effective for menopausal symptoms, especially hot flashes, but the lack of adequate longterm safety data (mainly on estrogenic stimulation of the breast or endometrium) precludes recommending long-term use.127 A more recent systematic review of 25 randomized, controlled trials from the Cochrane Library and MEDLINE from 1966 to March 2004 involving a total of 2348 patients concluded that the available evidence suggests that phytoestrogens available as soy foods, soy extracts, and red clover extracts do not improve hot flashes or other menopausal symptoms.128 In summary, the current clinical data on the effectiveness of botanical dietary supplements are mainly from open-label trials, which are burdened with methodologic flaws because of the placebo effect. For this reason it is useful to refer to the North American Menopause Society position statement on the treatment of vasomotor symptoms:
Tobacco and Alcohol
Cigarette smoking and excessive alcohol intake are related to increased risk of bone loss and cardiovascular disease. In women, more than two drinks per day is associated with an elevated risk of developing hypertension. On the other hand, mild consumption of alcohol (less than 7 units/week) in women may be associated with a cardioprotective effect. In a 12-year prospective study which included 85,709 healthy women age 35 to 59, Fuchs and colleagues concluded that mild to moderate consumption of alcohol could be associated with a decreased mortality rate for women, but mainly for those at high risk for coronary heart disease.121 Nevertheless, we should to be cautions when counseling for mild alcohol intake because it is also associated with increased incidence of breast cancer.122 This issue raises difficulties in the decision making for alcohol consumption for women.
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In recent years more natural products have gained popularity for treatment of vasomotor symptoms. Among these products phytoestrogens are perhaps the ones with more widespread use. Phytoestrogens are plant-derived substances structurally related to estrogens that have weak affinity to estrogen receptors.123 Phytoestrogen-containing dietary supplements commonly employed to relieve vasomotor symptoms include flaxseed, red clover extract, evening primrose oil, and soy compounds. The difficulty of consuming these botanical dietary supplements is that their purity, potency, and effectiveness are not well established; however, they are popularly believed to be safe and
For mild hot flashes, lifestyle-related strategies such as keeping the core body temperature cool, participating in regular exercise, and using paced respiration have shown some efficacy without adverse effects. Among nonprescription remedies, clinical trial results are insufficient to either support or refute efficacy for soy foods and isoflavone supplements (from either soy or red clover), black cohosh, or vitamin E; however, no serious side effects have been associated with short-term use of these therapies.129
Progesterone Cream from Yam Root Progesterone can be synthesized commercially from the wild yam. Its use for alleviating menopausal symptoms is growing in the United States. The scientific evidence is controversial at best. A 12-month randomized, controlled trial of 102 healthy postmenopausal women given either a quarter teaspoon of cream (containing 20 mg progesterone) or placebo to the skin daily showed that although there was a significant improvement in the relief of vasomotor symptoms (83% in the treatment group vs. 19% in the placebo group) there was no difference in the BMD.130 In contrast a randomized, double-blind, placebo-controlled, crossover trial performed in 23 postmenopausal women with vasomotor symptoms using a topical cream containing wild yam extract (Dioscorea villosa), vitamin E, and other oils found no detrimental side effects nor any improvement in menopausal symptoms as documented in weekly diaries for 3 months.131 Similar results were found in a parallel, double-blind, randomized, placebo-controlled trial in 80 symptomatic postmenopausal women comparing the effect of a transdermal cream containing
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Chapter 24 Menopause a progesterone (32 mg/daily) with a placebo cream. This study showed no changes in mood characteristics or sexual feelings, nor was there any change in blood lipid levels or in bone metabolic markers, despite a slight elevation of blood progesterone levels.132
Acupuncture A limited number of studies have evaluated Chinese acupuncture in alleviating mainly vasomotor symptoms. The lack of systematic controls in some of these studies makes it difficult to interpret the effectiveness of acupuncture. In a small prospective open trial, 11 menopausal symptomatic patients who underwent acupuncture for 5 weeks experienced a significant improvement in menopausal vasomotor symptoms without any changes in reproductive hormones or psychosocial or sexual symptoms, as measured by the Menopause Specific Quality of life Questionnaire.133 A pilot study evaluated the effectiveness of acupuncture for the treatment of menopausal symptoms in 15 patients with breast cancer treated with tamoxifen 20 mg/day. With the exception of libido, all of the other dimensions of the Green Menopause Index showed significant improvement (P<0.001) with acupuncture.134 Wyon and colleagues randomized 45 postmenopausal women with complaints of vasomotor symptoms to three study groups: electro-acupuncture, superficial needle insertion, or oral estradiol treatments for 12 weeks with a 6-month follow up. The patients in the electro-acupuncture group had a decrease in the mean number of hot flashes from 7.3 to 3.5, whereas superficial needle insertion patients decreased the mean number of hot flashes from 8.1 to 3.8. In the estrogen group, the number of hot flashes decreased from 8.4 to 0.8. The Kupperman index and the general climacteric symptoms score decreased and remained unchanged 24 weeks after treatment in all groups. Superficial needle insertion and electro-acupuncture were similar in efficacy to acupuncture treatment of vasomotor symptoms, although not as effective as estrogen.135 In Sweden a randomized, single-blind, controlled design was used to evaluate the effects of electro-acupuncture on general psychological distress related to climacteric symptoms in 30 postmenopausal women. In this study one group of patients received electro-acupuncture and another extremely superficial needle insertion, functioning as a near-placebo control. Patients were treated for 12 weeks and general psychological well-being, mood, and experience of climacteric symptoms were used as outcome measures. This study showed enhancement in the mood scale in the acupuncture group, but climacteric symptoms and psychological well-being improved in both placebo and treatment groups, suggesting that electro-acupuncture is not any better
than superficial needle insertion for amelioration of climacteric symptoms or improvement of well-being.136 Acupuncture may create tissue damage occasionally, but usually will not cause serious complications (i.e., pneumothorax, cardiac tamponade). The most common serious risk is the transmission of hepatitis viruses or other infectious agents through inadequately sterilized needles. Disposable needles, the standard of care in the United States, have eliminated this threat. In summary, alternative treatments for vasomotor symptoms lack carefully conducted placebo-controlled trials. Until these become evaluated all recommendations should be guarded.
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Natural menopause occurs between ages 45 and 55, with a median age of 51 for women in industrialized countries. By 2030, post menopausal women in the United States will represent 20% of the entire population. Menopause can be defined as more than 12 months of amenorrhea and an FSH level greater than 40 IU/L. Important factors affect the onset of menopause, including smoking, genetic factors, pelvic surgery, and metabolic factors. The most evident symptoms in early postmenopause are hot flashes and sleep disturbances. Causes of hot flashes other than hypoestrogenism include systemic diseases, neurologic causes, alcohol–medication interaction, drugs, and food additives. Two major long-term risks associated with menopause are osteoporosis and cardiovascular disease. The Women’s Health Initiative study findings should not be generalized to the whole menopausal population, but rather to the population studied and the specific treatment used in the trial. At the present time, the use of estrogen should be limited to the treatment of symptomatic menopausal women for the shortest possible time at the lowest dose. Maintenance estrogen therapy can be administered orally, by transdermal patches and gels, and vaginal creams. Selective estrogen receptor modulators have been found to be useful alternatives to prevent or treat osteoporosis in postmenopausal women. Selective serotonin reuptake inhibitors effectively decrease vasomotor instability in menopausal women by increasing the availability of serotonin in the central nervous system. A key element to preventing osteoporosis is maintaining a positive calcium balance. Adequate vitamin D is essential for optimal calcium absorption.
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124. Adams C, Cannell S: Women’s beliefs about “natural” hormones and natural hormone replacement therapy. Menopause 8:433–440, 2001. 125. Gokhale L, Sturdee DW, Parsons AD: The use of food supplements among women attending menopause clinics in the West Midlands. J Br Menopause Soc 9:32–35, 2003. 126. Mahady GB, Parrot J, Lee C, et al: Botanical dietary supplement use in peri- and postmenopausal women. Menopause 10:65–72, 2003. 127. Kronenberg F, Fugh-Berman A: Complementary and alternative medicine for menopausal symptoms: A review of randomized, controlled trials. Ann Intern Med 137:805–813, 2002. 128. Krebs EE, Ensrud KE, MacDonald R, Wilt TJ: Phytoestrogens for treatment of menopausal symptoms: A systematic review. Obstet Gynecol 104:824–836, 2004. 129. North American Menopause Society: Treatment of menopauseassociated vasomotor symptoms: Position statement of The North American Menopause Society. Menopause 11:11–33, 2004. 130. Leonetti HB, Longo S, Anasti JN: Transdermal progesterone cream for vasomotor symptoms and postmenopausal bone loss. Obstet Gynecol 94:225–228, 1999. 131. Komesaroff PA, Black CV, Cable V, Sudhir K: Effects of wild yam extract on menopausal symptoms, lipids and sex hormones in healthy menopausal women. Climacteric 4:144–150, 2001. 132. Wren BG, Champion SM, Willetts K, et al: Transdermal progesterone and its effect on vasomotor symptoms, blood lipid levels, bone metabolic markers, moods, and quality of life for postmenopausal women. Menopause 10:13–18, 2003. 133. Dong H, Ludicke F, Comte I, et al: An exploratory pilot study of acupuncture on the quality of life and reproductive hormone secretion in menopausal women. J Altern Complement Med 7:651–658, 2001. 134. Porzio G, Trapasso T, Martelli S, et al: Acupuncture in the treatment of menopause-related symptoms in women taking tamoxifen. Tumori 88:128–130, 2002. 135. Wyon Y, Wijma K, Nedstrand E, Hammar M: A comparison of acupuncture and oral estradiol treatment of vasomotor symptoms in postmenopausal women. Climacteric 7:153–164, 2004. 136. Sandberg M, Wijma K, Wyon Y, et al: Effects of electro-acupuncture on psychological distress in postmenopausal women. Complement Ther Med 10:161–169, 2002.
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Section 3 Adult Reproductive Endocrinology Chapter
25
Osteoporosis John Carey, Miriam Delaney, and Holly L. Thacker
INTRODUCTION Osteoporosis has reached epidemic proportions, affecting both genders and all races.1,2 In the United States, elderly white women are the at highest risk, and African-American or Hispanic American men may be at lowest risk.3 A 50-year-old white woman has a 40% lifetime risk of fracture and a 14% risk for hip fracture. Osteoporotic fractures are associated with substantial morbidity and increased mortality. Worldwide, there were approximately 1.7 million hip fractures in 1990, and this number is expected to triple by 2050 as the number of persons older than age 50 increases. The cost of treating fractures is rising.4 Direct costs alone for the treatment of osteoporotic fractures in the United States total greater than $10 billion annually.1,5,6 In a study of over 200,000 postmenopausal women in 34 states in the United States who underwent bone mineral density (BMD) testing using peripheral measurement techniques, almost 40% had low BMD and 7% had osteoporosis.6 Great advances have been made in the past few years in both the diagnosis and treatment of osteoporosis. By the turn of the millennium in the United States, measurement of BMD had become widely available, making the diagnosis of osteoporosis easier. In addition, several biochemical markers of bone turnover allow more precise monitoring of patients on therapy. Newer scoring methods for assessing fracture risk have been developed.7 Lifestyle changes, fall prevention programs, nutritional supplements, and hip pads decrease the risk of fracture.1,8–10 Several medications are currently available that effectively decrease the risk of future fracture. Unfortunately, despite these advances, studies show that many women age 40 and older have not had the opportunity to discuss management of this disease with their physicians,11 and many patients who suffer from an osteoporotic fracture are not evaluated or treated for their disease.12 Although management of fractures is appropriate, the primary aim for the treating physician should be fracture prevention.
PATHOPHYSIOLOGY Definition Osteoporosis is a disease of the skeletal system characterized by decreased bone strength leading to increased susceptibility to fracture.1 Microarchitectural changes result in less bone, which is of poorer quality, thus predisposing the skeleton to fractures
that may occur with little or no trauma.1 The first released Surgeon General’s report contains a comprehensive report on osteoporosis.2
Basic Bone Physiology The skeleton is composed of cortical and trabecular bone. Cortical bone is primarily found in the long bones and trabecular bone in the axial skeleton. The primary function of cortical bone is structural, whereas the primary function of trabecular bone is calcium homeostasis. Skeletal tissue is in a constant state of turnover with destruction of old bone by osteoclasts and formation of new bone by osteoblasts. This process occurs throughout life at various sites in the skeleton termed bone remodeling units. Each bone remodeling unit contains multinucleated osteoclasts formed from fusion of monocytes and macrophages that migrate to different sites in the skeleton from the circulation. Once there, osteoclasts erode cavities deep into the bone surface termed a resorption pit. This process takes several weeks and is slower in cortical bone. Once the resorption pit has been formed, the osteoclasts are replaced by osteoblasts that lay down new bone, repairing the resorption cavities slowly over several months. Under normal circumstances both processes occur concurrently in an intimately regulated fashion known as coupling, which balances functions to maintain a healthy intact skeleton. Early in life, growth and accumulation of skeletal tissue occur. Peak bone mass is reached in adulthood, but the age at which this is achieved varies depending on the skeletal site and measurement techniques used. Currently available evidence suggests this occurs at the hip as soon as the third decade, several years later for the whole body, and maybe even longer in other bones.1,13 Peak bone mass is a major determinant of future osteoporosis risk and optimal achievement is usually multifactorial. Genetic influences account for the majority of variability in BMD and is the most critical determinant of peak bone mass in adulthood.13–16 Daughters of women with osteoporosis, and mothers with hip fractures attain lower peak bone mass than age-matched controls.14,15 Peak bone mass differs among racial groups, with African-American women having the highest BMD and others differing between measured sites and studies.3,17,18 Asian women may have lower BMD than white women but, interestingly, also have lower rates of hip fracture. Differences are likely related to genetic variation between races, local environmental factors, and primarily body weight and bone size.18,19
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Section 3 Adult Reproductive Endocrinology Basic Mechanisms of Bone Disorders Uncoupling of bone turnover leading to either increased or decreased formation may result in either net bone gain, as occurs in Paget’s disease of bone, or net bone loss as occurs in postmenopausal women, in primary hyperparathyroidism, and in rheumatoid arthritis.20–23 Most disorders of the skeleton result from excessive osteoclastic activity.20 As a consequence of estrogen deficiency after menopause, there is early and rapid loss of cancellous bone, concomitant with and followed by a more gradual loss of cortical bone. Exogenous estrogen can decrease or prevent this altered skeletal remodeling.24 This bone resorption occurs by two main biochemical pathways: the cathepsin K and the metalloproteinase-dependent pathways. Postmenopausal bone loss is thought to occur mainly via the former.25
Medical Problems Associated with Osteoporosis Certain medical disorders and medications may significantly impact the attainment of peak bone mass. Malabsorption syndromes, cystic fibrosis, anorexia nervosa, inflammatory arthritis, and other diseases are associated with lower bone mass compared to age-matched controls. Although weight can have a significant impact on the measurement of BMD,18 severely underweight young women have lower BMD and a higher risk of fracture. Certain medications such as glucocorticoids and phenytoin, vitamin D deficiency, and low calcium diets can also impair skeletal acquisition. Both vitamin D deficiency and low calcium intake are prevalent in our society and increasingly recognized worldwide. Periods of more rapid growth may require higher calcium intake.13,20 Recent evidence suggests that genetic alteration of vitamin D-binding proteins may increase the risk of premenopausal fractures.21
Social Behavior and Bone Mass
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Although weight-bearing exercise generally increases BMD, the effects may be short-lived and may return to baseline levels after cessation of exercise regimens.28 Although moderate doses of alcohol have no deleterious effects on BMD, and, in fact, may even be of benefit,29,30 excessive alcohol consumption is associated with lower bone mass and an increased risk of osteoporosis.31 Although not all studies agree, smoking is generally considered to have a deleterious effect on the skeleton and is associated with an increased risk of fracture.24 In young women, eating disorders such as anorexia nervosa and excessive athletic training are associated with loss of BMD or BMD.1,13,26 Young women with anorexia nervosa may have irreversible skeletal changes and have a significantly higher risk of fracture.26 The female athlete triad of intense exercise regimens, with resultant loss of critical body fat and subsequent hypothalamic amenorrhea and low bone mass, are important elements to consider in young active women. This triad is frequently associated with eating disorders that may be further detrimental to skeletal health. Female athletes weighing less than 50 kg have a higher incidence of amenorrhea than those weighing more than 60 kg and amenorrheic female athletes have significantly lower BMD than controls and a higher number of fractures. These women may present with stress fractures as the first sign of their
disease; thus, every woman with a stress fracture should have a careful dietary, exercise, and menstrual history taken. Importantly, these women may not achieve their peak bone mass if undetected. Bone loss in these young women is likely multifactorial.13,26
Hormonal Influence on Bone Mass Estrogen
Estrogen and biomechanical strain appear to be the primary physiologic factors necessary for maintenance of bone mass. Estrogen decreases bone turnover and preserves homeostatic skeletal remodeling. At the cellular level there are two main cell types responsible for the maintenance of skeletal homeostasis: osteoclasts and osteoblasts, influenced by many regulatory genes; several hormones, particularly estrogen, testosterone, parathyroid hormone, and vitamin D; and a variety of cytokines.20,24,32 Estrogen increases osteoclast apoptosis, but its role in osteoblastic function is not fully understood.24 Estrogen decreases osteoclast activity and bone resorption by modulating the production of two essential cytokines that regulate osteoclast number and activity, and possibly osteoblast function as well.20 Estrogen inhibits production of tumor necrosis factor α (TNF-α)33 but increases production of osteoprotegerin (OPG).24 TNF-α promotes bone resorption by decreasing osteoblast activity and directly inducing the differentiation of osteoclast progenitors into mature osteoclasts. TNF-α also appears to induce osteoblastic cells to stimulate osteoclastic bone resorption. Thus, estrogen decreases bone resorption by inhibiting TNF-α production. In postmenopausal women estrogen therapy inhibits TNF-α release in a dose-dependent manner from peripheral blood mononuclear cells34 and markedly reduces TNF-α mRNA expression in bone biopsy specimens.35,36 In murine models, blockade of TNF-α is not detrimental to skeletal maturation.37 Mice deficient in the p55 TNF receptor are protected against ovariectomy-induced bone loss.38 Surgically induced estrogen deficiency in mice causes significant bone loss, which is mediated via the p55 TNF receptor and can be prevented by blockade of TNF-α.23,37 The effect of estrogen on OPG is even more complex. Osteoclasts possess transmembrane receptors referred to as receptor activator of nuclear factor-κB, or RANK. Activation of RANK by tumor necrosis factor-related activation-induced cytokine, or TRANCE (also known as RANK ligand) results in increased bone resorption. However, OPG act as “decoy” receptors that prevent TRANCE from binding and activating RANK receptors. Thus, estrogen stimulation of OPG production decreases bone resorption by decreasing TRANCE binding to RANK. Mice with excess OPG exhibit increased osteoclastic activity and an osteopetrotic phenotype,39 whereas mice deficient in OPG suffer severe osteoporosis.40 Conversely, OPG protects TNF transgenic mice from generalized bone loss.41 1,25-OH active vitamin D potentiates the action of OPG. Androgens
Androgens also play a critical role in skeletal development, maturation, and preservation. Differences in estrogen and testosterone production and in tissue sensitivity to these hormones probably
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Chapter 25 Osteoporosis account for most of the skeletal differences seen between men and women. At the present time it appears that both are essential for bone health in women and men. Sources of testosterone in women arise mainly from conversion in peripheral tissues but also from central production in small amounts in the ovaries and adrenal glands, whereas in men 95% is derived from testicular secretion, and production of the various isoforms is highly tissue specific. More detailed explanations of the production and removal of these hormones can be found elsewhere in the book. Testosterone receptors are present on several types of osteocytes, in a manner analogous to estrogen receptors. Testosterone actions include decreasing osteoclast and osteoblast apoptosis and stimulating osteoblast proliferation, which overall increases bone formation and reduces bone resorption. However, whereas estrogen opposes periosteal apposition of bone, testosterone promotes it, which may account for why men generally have larger bones than women. In addition, testosterone plays an important role in epiphyseal maturation and closure. The precise molecular pathways in bone resulting from androgenic stimulation are less well-described than for estrogens. Many of the effects of androgens on skeletal tissue may be mediated by increased production of transforming growth factor (TGF)-β and decreased production of interleukin-6.24,42 Studies in female rats have shown that blockade of the androgen receptor may result in significant bone loss, and in men androgen deprivation results in bone loss.43,44 The remainder of this discussion applies mainly to female bone health. Hormonal Therapy and Osteoporosis
Several drugs that are routinely used in gynecology directly influence bone metabolism and can result in osteoporosis. Gonadotropin-releasing hormone (GnRH) agonists are commonly used for the treatment of endometriosis and are well-known causes of bone loss secondary to hypoestrogenemia. Depot medroxyprogesterone, a very popular contraceptive agent among adolescents, is also associated with bone loss secondary to hypoestrogenemia. As a result, depot medroxyprogesterone now carries a black box warning issued by the U.S. Food and Drug Administration (FDA) in 2004 reporting bone loss with prolonged use. Finally, aromatase inhibitors, increasingly being prescribed to women with breast cancer, are associated with a higher risk of fracture compared to tamoxifen.
Pregnancy and the Postpartum Period Significant bone loss occurs during pregnancy, as assessed by BMD testing.45,46 Although earlier reports have suggested that heparin use in pregnancy may result in significant bone loss during pregnancy, a recent randomized trial showed treatment with low molecular weight heparin throughout the course of pregnancy did not result in significantly more bone loss in this study of women with recurrent miscarriages compared to individuals who used only aspirin throughout the course of their pregnancy.49 Breastfeeding in the postpartum period can further exacerbate bone loss, but a recent study shows that the effect may not be sustained, with the majority of women returning to baseline within a year after the birth of their child.46
Age and Postmenopausal Status With aging, there is an alteration in the rates of bone formation and destruction where the process switches from one of gradual net gain to one of loss. This loss along with microarchitectural deterioration results in significant compromise of bone strength.47 More dramatic changes occur most noticeably during and after menopause. (In contrast, bone loss in men tends to be more constant over time.) Postmenopausal bone loss is biphasic in women (who are not on antiremodeling therapy), with an initial rapid bone loss in the first few years of menopause followed by a more gradual decline in later years.48 Women with higher levels of bone markers lose more bone and have a higher rate of fracture than women with normal or low levels, even after adjustment for BMD and hormonal status. However, postmenopausal women with high bone turnover markers and low estradiol levels have an even higher rate of fracture.48–50 Estrogen therapy preserves BMD and suppresses bone turnover markers, but discontinuation leads to a rapid increase in bone turnover markers and significant bone loss similar to that seen in recently postmenopausal women but greater than agematched controls.51 Women undergoing surgical menopause may be at higher risk for short-term bone loss compared to women experiencing natural menopause.48 Hyperparathyroidism
Secondary hyperparathyroidism, impaired vitamin D metabolism, and vitamin D and calcium deficiency are also critical elements in age-related bone loss, and their importance and prevalence has been increasingly recognized. Calcium absorption varies among individuals and is influenced by many factors, primarily vitamin D.13,52 Decreased ability to absorb calcium is associated with increased risk of fracture in elderly women.53 Primary osteoporosis is associated with decreased calcium absorption, lower vitamin D levels, and compensatory increases in parathyroid hormone levels.24,54 Vitamin D Deficiency
Vitamin D in humans is primarily obtained from ultraviolet light exposure, with a few foods, such as fish oils, containing significant amounts. Many foods and vitamins are now supplemented with vitamin D, but the actual amount in these foods may vary considerably. Vitamin D formed in the skin after exposure of 7dehydrocholesterol to ultraviolet light is metabolized in the liver to 25-hydroxyvitamin D3 and further in the kidney to 1,25hydroxyvitamin D3, the biologically active form. Vitamin D, required throughout life, influences several important steps in calcium metabolism, maintaining adequate serum calcium levels. Vitamin D increases absorption of calcium and phosphorus from the gut, increases their reabsorption from the kidney, and decreases skeletal mobilization of calcium. Deficiency of vitamin D impairs absorption of calcium, which is counteracted by increased parathyroid hormone levels and osteoclastic activity to resorb skeletal tissue to maintain serum calcium level.13,52,54 Vitamin D deficiency is prevalent in elderly women with hip fractures,55 due to decreased skin conversion, decreased sun exposure, and low dietary intake.52
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Section 3 Adult Reproductive Endocrinology Table 25-1 Common Associations or Secondary Causes of Low Bone Mass and Secondary Causes of Osteoporosis56–59,61,74 Category
Specific Examples
Medications
Corticosteroids Depot medroxyprogesterone Heparin Gonadotropin-releasing hormone analogues Aromatase inhibitors Anticonvulsants Thyroxine Cyclosporine and tacrolimus Methotrexate Cyclophosphamide Neuroleptics Lithium Alcohol excess
Endocrine diseases
Hypogonadism Hyperparathyroidism Hyperthyroidism
Inflammatory diseases
Rheumatoid arthritis Ankylosing spondylitis Psoriatic arthritis
Malabsorption syndromes
Celiac disease Short bowel syndrome Cystic fibrosis
Deficiency states
Vitamin D deficiency
Renal diseases
Renal insufficiency Renal osteodystrophy Renal tubular acidosis Idiopathic hypercalciuria
Bone marrow disorders
Multiple myeloma Thalassemia
Genetic diseases
Osteogenesis imperfecta Ehlers-Danlos syndrome Turner’s syndrome
Prolonged immobilization
Stroke Quadriplegia Space flight
CLASSIFICATION AND GENERAL PRINCIPLES OF INVESTIGATION
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Primary osteoporosis is a disease mainly of the elderly. The underlying mechanisms for this appear to be multifactorial, including having lower peak bone mass, experiencing rapid bone loss after menopause, and having an associated condition, such as a hypogonadal state, poor nutrition, and vitamin D deficiency. There is likely a strong genetic predisposition to develop osteoporosis. An evaluation should be undertaken in patients diagnosed with osteoporosis because certain contributing factors to low bone mass are also more common in these women, including vitamin D deficiency, hypogonadism, and thyroid disease. Secondary osteoporosis should be considered whenever there is any clinical suspicion of a disorder known to affect bone or calcium metabolism. A careful history, including a list of medications both past and present, is essential given the extensive list of diseases and treatments associated with or known to cause low bone mass or bone loss (Table 25-1). Previous studies have shown that up to 70% of patients with osteoporosis may have other diagnoses contributing to low bone mass.56,57 Secondary causes of low bone mass may be more prevalent in perimenopausal women and in men, although studies are limited on the prevalence of such disorders in postmenopausal
women with low bone mass.1,58 An evaluation of possible causes of low bone mass should be undertaken in anyone for whom this is suspected. It is generally recommended that at least basic chemistries are obtained, including complete blood count, thyrotropin level, 24-hour urine for calcium excretion, intact parathyroid hormone level, and a 25-hydroxyvitamin D3 level in all patients.56,59,60 Whether radiographic imaging or other laboratory studies, such as serum and urine protein electrophoresis, parathyroid hormone level, or cortisol levels should be undertaken is a decision that needs to be taken by the individual physician, because ancillary testing should be based on the clinical impression.
Glucocorticoid-induced Osteoporosis Glucocorticoid-induced osteoporosis is a distinct form of secondary osteoporosis. Although an extensive list of medications can both directly and indirectly affect the skeleton, glucocorticoidinduced osteoporosis is the most common drug-induced metabolic bone disease.61,62 Glucocorticoids are often prescribed in both young and older individuals for treatment of medical conditions, such as rheumatoid arthritis, asthma, or other chronic obstructive pulmonary disease. Vertebral fractures will develop in 30% to 50% of patients taking chronic glucocorticoids, and patients have an increased risk of fracture at any site compared to nonusers. The risk of fracture is related to the daily dose, duration of therapy, and older age.63 Acute corticosteroid excess leads to decreased calcium absorption from the gut, a marked early increase in bone resorption, and decrease in bone formation with resultant increased excretion of urinary calcium. There can be very significant bone loss during this initial phase. Chronic use leads to other changes, including hypogonadism, resulting in a generalized suppression of skeletal remodeling.62 The American College of Rheumatology has published guidelines for the management of patients with glucocorticoid-induced osteoporosis.63
CLINICAL EVALUATION History Osteoporosis is generally a painless and symptom-free disease until fractures occur. Fractures may be very painful or painless, with up to two thirds of vertebral fractures being clinically silent.64 Loss of height is the most common finding in women with osteoporosis. History taking should include questions about height loss, back pain, dietary calcium intake, eating disorder history, age of menarche and menopause, and cycle history during menstrual years. Other risk factors for low bone mass should also be evaluated, including major illnesses, medications (particularly glucocorticoid use), a history of prolonged amenorrhea, and risk factors for fracture such as poor vision, recent falls, and findings of risk on a fall risk assessment. Bone pain, fevers, and weight loss are not features of osteoporosis, and the presence of such symptoms in the absence of a fracture should alert the clinician to the possibility of a different diagnosis. Paget’s disease of bone, malignancy, osteomalacia, and osteomyelitis can all present with bone pain. Back pain can be seen in osteoarthritis and malignancy and is only a feature of osteoporosis patients who fracture. Dental loss is associated with postmenopausal osteoporosis.
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Chapter 25 Osteoporosis Physical Examination
Table 25-2 World Health Organization Diagnosis of Osteoporosis in White Women Using Dual Energy Absorptiometry67,68
Results of physical examination may be normal. However, more obvious features of osteoporosis include kyphosis, which if marked can give the appearance of a “hump,” increased limb-totrunk ratio, decreased rib to pelvic brim height in the upright position, and spinal tenderness. Multiple fractures can lead to chronic pain, dyspnea, and depression. Blue sclera are seen in osteogenesis imperfecta, which can present as fragility fractures.
Diagnostic Imaging Any history of a fragility fracture should immediately alert the physician to consider a diagnosis of osteoporosis. Although microarchitectural changes seen on bone biopsy specimens definitively diagnose osteoporosis, this is not a practical approach for most women. The need for noninvasive methods to measure bone strength has led to the development of dual energy absorptiometry (DXA) techniques that measure BMD of the skeleton. BMD accounts for the majority of bone strength. Studies show that measurements obtained by this technique have a strong linear correlation with fracture risk.6,65,66 Additional factors influencing bone strength include bone size and quality. Osteoporosis may be diagnosed with findings of low BMD on DXA in postmenopausal women. Lastly, newer methods for assessing fracture risk and bone strength continue to be developed, with exciting techniques such as virtual bone biopsy using microcomputed tomography or magnetic resonance imaging appearing very promising. Dual Energy Absorptiometry
The advent of DXA has revolutionized our ability to quickly and accurately measure bone mass noninvasively. Results are expressed in grams per centimeter squared and as T- and Z-scores, which are expressions of BMD in standard deviations compared to a normally distributed reference population. The T-score compares the results to young, healthy white women at peak bone mass, whereas the Z-score compares subjects to agematched, and usually sex-matched and racially matched, controls (depending on the DXA machine used). A strong linear relationship exists between BMD and fracture risk, such that for each standard deviation below 1 there is an approximately doubling of fracture risk.1,6,65,66 A low BMD is the best individual predictor of future fracture risk in postmenopausal women without prior fracture.6 Women with low BMD and previous fractures have a much higher risk of future fracture.7,64 The addition of age66 and other risk factors such as estrogen deficiency greatly increases the utility of BMD testing to predict fracture risk.7,65 Although World Health Organization criteria can be applied to BMD measurements to diagnose osteoporosis,67 they reflect a consensus of expert opinion, and significant problems exist using such a method as the sole means of diagnosing osteoporosis68 (Table 25-2). Although these criteria may be used to identify individuals at increased risk for fracture, they are not a panacea for either diagnosis or treatment of this disease. First, most fractures occur in individuals who do not have osteoporosis using these criteria. Second, these criteria were established for use with central DXA technology; their application to other modalities used to measure BMD remains unclear. Third, they were intended for use primarily in postmenopausal white women; their applicability to other populations such as premenopausal women is less clear.
Bone Mineral Density T-Score
World Health Organization Classification
≥ –1.0
Normal
–1.1 to –2.4
Osteopenia
≤ –2.5
Osteoporosis
≤ –2.5 and the presence of a fragility fracture
Severe (established) osteoporosis
Table 25-3 Risk Factors for Fracture from Highest to Lowest Risk Prior fragility fracture Low bone density (particularly T-score ≤ −1.7)4 Maternal history of osteoporotic fracture Low body mass index Smoking history
Some of these shortcomings were evident in a recent very large study of postmenopausal women in the United States, in which Asian and Hispanic women had significantly lower BMD at one measured site than white women but a similar risk of fracture.6 Finally, other fracture risk factors may be significant, such as age or prior fractures, and the addition of such factors to fracture risk assessment greatly increases the prediction of future fracture risk.7,65,66,68 (Table 25-3). As a result, attempts have been made to clarify how to best use DXA technology to diagnose osteoporosis in different populations and using different technologies,69 and also how to predict increased fracture risk.7,65 In conclusion, although a useful measure for predicting increased fracture risk, BMD measurement is only one assessment tool for such predictions, and an overall clinical assessment of an individual’s fracture risk should be used when assessing whether a woman is likely to sustain an osteoporotic fracture. A T-score of ≤ –1.7 appears to be an important cutpoint for fracture risk.4 Because osteoporosis is an asymptomatic disease (until a fracture occurs), screening with DXA should be considered in certain individuals, such as postmenopausal women with additional risk factors for osteoporosis. Presently the International Society for Clinical Densitometry recommends BMD testing for the following groups of people:69 ● ●
● ●
● ●
all women age 65 and older (regardless of race) younger postmenopausal women with risk factors for osteoporosis all adults with a fragility fracture all individuals with a disease or condition or taking a medication that could be detrimental to their skeleton to monitor patients receiving bone therapy men age 70 or older.
Although T-scores can be used to diagnose osteoporosis with central DXA technology, there are clarifications and important exceptions to this outlined in the recent International Society for Clinical Densitometry consensus statement:69
375
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Section 3 Adult Reproductive Endocrinology 1. The World Health Organization classification system should be used and applied to postmenopausal women (and men older than age 50). 2. The lowest T-score should be used (lumbar spine, hip, or one-third forearm) to report diagnosis. 3. In premenopausal women, the diagnosis of osteoporosis should not be based solely on BMD criteria. 4. Z-scores, not T-scores, should be used for diagnostic reporting in children and premenopausal women. 5. Although peripheral BMD techniques are useful for assessment of fracture risk, World Health Organization criteria should not be applied to measurements with these techniques. Although peripheral DXA is not as accurate as central DXA and has significantly less precision, peripheral studies are valuable screening tests given their ease of use, and they do predict fracture risk.6,65,66 Individuals with low BMD using peripheral devices should be referred for central DXA of the hip and spine, which remains the gold standard for measuring BMD. Monitoring of therapy should be performed by central DXA only. Lastly, discordance has been noted between measurements of BMD at different sites, where there may be significant differences between hips or the hip and spine readings. Fracture risk prediction is most accurate for the actual site assessed by BMD, and the lowest International Society for Clinical Densitometry recommended site should be used for diagnosis.70 Currently, the International Society for Clinical Densitometry does not recommend using Ward’s area or individual vertebra for this assessment.67 Biochemical Markers of Bone Turnover
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Bone turnover markers are essentially organic fragments of skeletal tissue formed during skeletal remodeling. They are released into the circulation, and many undergo renal excretion and thus can be measured in either serum or urine. Bone turnover markers are the result of two basic processes of bone turnover: (1) formation and (2) resorption. Production can be affected by many factors, most notably several hormones, menopausal status, glucocorticoids, fasting, and circadian rhythm. In general, formation markers are affected to a much lesser degree than resorption markers by these factors, and serum markers have less variability than urinary markers. However, variation can be dramatic from marker to marker, making knowledge of the intricacies of the individual test imperative to accurately interpret the results. Among the more widely available resorption tests are serum and urine aminoterminal cross-linked telopeptide of collagen and carboxyterminal cross-linked telopeptide of collagen, which should be performed after an overnight fast. Formation tests include serum bone-specific alkaline phosphatase and osteocalcin (Table 25-4). Newer assays are cheaper, easier to run, and provide more reliable measurements with markedly better performance characteristics than their predecessors. Bone turnover markers tend to respond significantly faster to treatment for osteoporosis than BMD, making their measurement particularly useful in monitoring therapy. With certain medications, such as the oral bisphosphonates, significant changes can occur within several weeks of starting therapy.71–73 Many diseases and medications increase a woman’s risk for developing osteoporosis (see Table 25-1). Routine laboratory
Table 25-4 Commonly Used Bone Turnover Markers Bone Marker
Formation
Resorption
Measured
Bone-specific alkaline phosphatase (BSAP)
Yes
–
Serum
Osteocalcin
Yes
–
Serum
Aminoterminal propeptide of type I collagen (PINP)
Yes
–
Serum
Carboxyterminal propeptide of type I collagen (PICP)
Serum
Yes
–
Aminoterminal cross-linked telopeptide of type I collagen (NTX1)
–
Yes
Serum or urine
Carboxyterminal cross-linked telopeptide of type I collagen (CTX1)
–
Yes
Serum or urine
Pyridinoline cross-linked carboxyterminal telopeptide of type I collagen (ICTP)
–
Yes
Serum
Tartrate-resistant acid phosphatase (TRAP-5β)
–
Yes
Serum
Deoxypyridinoline cross-linked carboxyterminal of collagen (DPD)
–
Yes
Urine
Table 25-5 Recommended Baseline Testing for Occult Causes of Low Bone Mass or Secondary Causes of Bone Loss Complete chemistry (including calcium, phosphorus, creatinine, and bicarbonate levels and liver function tests) Complete blood count 24-hour urine collection for calcium excretion Intact parathyroid hormone 25-hydroxyvitamin D level Thyrotropin
studies are necessary to look for metabolic abnormalities or diagnoses and to ensure normal renal and calcium metabolism before prescribing therapy (Table 25-5). Vitamin D levels in the lower limit of normal warrant replacement until the level is normalized.43,74 More profound vitamin D deficiency and osteomalacia is uncommon, but an elevated alkaline phosphatase level or increased parathyroid hormone level should prompt further evaluation of vitamin D metabolism, especially in the presence of normal liver function tests. Parathyroid hormone levels may be mildly elevated in the face of vitamin D deficiency and should return to normal with correction.54
Other Diagnostic Modalities Bone Biopsy
Bone biopsy is usually unnecessary, with a few noteworthy exceptions where there may be doubt about the diagnosis, such as in renal osteodystrophy. Most of the newer DXA technologies now come with the point-of-service imaging of the thoracic and lumbar spine. The procedure, such as lateral vertebral assessment
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Figure 25-1
Example of a normal lateral vertebral assessment.
(Figs. 25-1 and 25-2), can be used to image the spine for fractures quickly and easily at significantly lower cost and radiation dose than conventional imaging techniques.75 This is particularly useful for decision-making, with spine fractures often being asymptomatic, and the presence of a fracture being the single best predictor of future fractures. Prevalent spine fractures are associated with a fivefold increase in the risk of fracture over the next 12 months.64 In the presence of fragility fractures where the T-score does not necessarily meet the World Health Organization BMD criteria for osteoporosis, treatment for osteoporosis is warranted. Plain x-rays and review of old x-ray films may also be useful in certain instances. Despite the ease of diagnosis, most published studies show that persons who fracture or are at high risk of fracture are often not evaluated or treated for their disease. A recent study shows that an alarmingly small percentage of women with hip fractures undergo formal BMD testing or treatment for their disease.12 In another study of more than 62,000 women older than age 50 in England, 3.2% of whom were taking glucocorticoids, less than half of those on steroids were on fracture prevention therapy, and this number declined to less than one third in the oldest age group with the highest number of fractures.76
PREVENTION OF OSTEOPOROSIS Physicians treating postmenopausal women at risk for osteoporosis should stress preventive therapy with their patients
Figure 25-2 fracture.
Lateral vertebral assessment showing a T11 compression
whenever possible. Preservation of bone mass can help prevent the onset of osteoporosis. Because rapid bone loss occurs during and immediately after menopause, a baseline evaluation, including evaluation of risk factors, should be undertaken.
Screening Consideration should be given to screening BMD and also bone turnover markers. Women with other disorders that predispose them to more rapid or severe bone loss such as vitamin D deficiency, hyperparathyroidism, and hypercalciuria should have disease-specific treatments for those conditions and BMD testing. For instance, parathyroidectomy for primary hyperparathyroidism may help restore bone mass and calcium metabolism. Prescribing a thiazide diuretic such as hydrochlorothiazide may increase BMD by partially inhibiting renal calcium excretion for women with idiopathic hypercalciuria.
REDUCTION OF FRACTURE RISK AND TREATMENT OF OSTEOPOROSIS Once a woman is diagnosed with osteoporosis and has undergone an evaluation of their disease status, attention is then focused on instituting appropriate therapy. Treatment for established osteoporosis involves a comprehensive assessment of the woman’s modifiable and nonmodifiable risk factors and
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Section 3 Adult Reproductive Endocrinology associated conditions to provide the most appropriate therapeutic options. Appropriate pharmacologic intervention should then be instituted.
and recommends FDA-approved therapies proven to be safe and effective.88 Risk Factors for Pharmacologic Therapy
Nonpharmacologic Intervention for Fracture Reduction Basic strategies to educate women about fall risk, safe footwear, calcium and vitamin D supplementation, smoking cessation, and the need for moderate, regular weight-bearing exercise are essential. These simple therapeutic options, which can be instituted by a nurse or other healthcare provider, coupled with careful observation and reassurance, may be all that is necessary for many individuals. A multifactorial approach to fall prevention is effective.8 Regular weight-bearing exercise has been shown to increase or preserve BMD in young, middle-aged, and elderly individuals in numerous studies9,77,78 and also increases muscle tone, helping prevent falls. Hip protectors, if worn by the patient, have been shown to prevent hip fractures in patients who are at significant risk of falling.10 Smokers have lower hip BMD than nonsmokers,79 and smoking cessation may have favorable effects on bone turnover markers.80 Alcohol in moderation may have a positive effect on BMD, but excessive alcohol use should be discouraged given its association with lower bone mass and increased risk of fracture.
Calcium and Vitamin D Both calcium and vitamin D stabilize BMD, at least temporarily,81–83 have favorable effects on biochemical markers of bone turnover,84,85 and reduce the risk of fracture.83,86 Chapuy and colleagues, in a large randomized, placebo-controlled trial of more than 3000 women with osteoporosis, have demonstrated that a combination of calcium and vitamin D significantly reduced the risk of vertebral, nonvertebral, and hip fractures.86 This may, in part, be explained by the observation that additional supplementation with vitamin D has been shown to significantly reduce fall risk in elderly women compared to calcium supplementation alone.87 Stabilization of bone mass appears to be mediated through the reversal of secondary hyperparathyroidism seen in chronic vitamin D deficiency states.83 Vitamin D levels that are below normal reference ranges should be replaced with 50,000 IU per week of oral vitamin D, and levels should be rechecked after several weeks of replacement therapy. Failure to reach midnormal ranges may necessitate higher or more prolonged dosing. Given the significant lifetime risk of fracture for a woman age 50, more intensive therapy may be indicated, depending on risk factors, low bone mass on DXA testing, or increased markers of bone turnover.
Pharmacologic Therapy
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Therapies such as systemic estrogen therapy, selective estrogen receptor modulators (SERMs), and bisphosphonates have been shown to preserve BMD, decrease markers of bone turnover, and reduce the risk of fracture in postmenopausal women. The American College of Obstetrics and Gynecology recommends treatment of osteoporosis in all postmenopausal women with fragility fractures and postmenopausal women with central DXA T-scores <−2, or T-scores <−1.5 who have additional risk factors,
In selecting pharmacologic treatment, the clinician should should also screen the woman for other risk factors that may affect choice of therapy. Avoiding use of estrogen or estrogen-like therapies in those women with a personal history or strong family history of thromboembolic phenomena may be prudent.89,90 Breast cancer risk assessment by history and Gail model predictors may lead the clinician to the choice of a SERM such asraloxifene (if there are no menopausal symptoms). Similarly, raloxifene should be avoided in persons with a history or significant risk factors for venous thromboembolism.91 Bisphosphonates should not be used in persons whose creatinine clearance is less than 35 mL/minute, and alendronate should be avoided in persons with a history or suggestive symptoms of peptic ulcer disease, gastroesophageal reflux, or esophageal stricture.92 Teriparatide should not be used in persons with hyperparathyroidism, hypercalcemia, those with malignancy or a significant history of radiation treatment (such as radiation for breast cancer), or persons with Paget’s disease of bone.91 Estrogen Therapy
Estrogen therapy has been considered the mainstay of osteoporosis therapy for postmenopausal women, especially in terms of prevention. Much of the rationale for this emanated from work showing that estrogen deficiency leads to accelerated bone loss and that elderly women with the lowest estrogen levels have the highest risk of fracture.93,94 Hormone therapy (HT) increases BMD,95 slows bone loss,94–96 decreases skeletal turnover,94,97 and prevents both vertebral, nonvertebral, and hip fractures.94,96,98–100 Discontinuation of estrogen therapy leads to further loss of bone.51,95–105 Media attention to the results from the Women’s Health Initiative (WHI) study have raised concern as to the overall benefit-to-risk ratio of HT in a large population of late postmenopausal women who were not risk stratified as to a general preventive therapy. Although there was an increased risk of stroke, deep venous thrombosis, gallbladder diseases, and breast cancer diagnosis in those older women taking combined estrogen/ progestin therapy, the WHI also showed that HT reduced the risk of hip fracture by 50% as well as the risk of colon cancer.90 The estrogen-only arm of the WHI showed that there was a similar increased risk of nonfatal stroke but no increased risk of breast cancer or cardiovascular disease, and fracture reduction was seen at all sites.89 Although data from the recent WHI have shown that treating all postmenopausal women with estrogen for osteoporosis prevention is not prudent, it remains unclear whether lower doses or alternative bone preparations are safer. In premenopausal women with the athletic triad and eating disorders, hormonal contraceptive therapy may be of benefit.26,102 Treatment that includes nutritional supplementation, counseling, calcium and vitamin D supplementation, and hormonal contraceptives can be beneficial.13,26,102–104 The benefits of estrogen alone on BMD are unclear in women with eating disorders, with some studies showing little or no benefit.26,104 A more detailed review of the risks and benefits of estrogen therapy in premenopausal and postmenopausal women is outside the scope of this chapter.
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Chapter 25 Osteoporosis However, the International Menopause Society Position Statement 2004 asserts that HT remains a principal tool for preventing postmenopausal bone wasting, fracture, and loss of connective tissue, as well as effects on quality of life for symptomatic women. Selective Estrogen Receptor Modulators (SERMs)
SERMs are pharmacologic compounds that have estrogen-like effects in certain tissues. This is an area of intense investigation by the pharmaceutical industry as they attempt to provide “designer” therapies that can be targeted to individuals with different disease risk factors. Raloxifene was approved by the U.S. FDA in 1997 for the prevention and treatment of osteoporosis at an oral dose of 60 mg daily.100 The results of the MORE trial, a large, multicenter, randomized, placebocontrolled trial, showed that treatment with raloxifene preserved BMD,105 reduced bone turnover,85,100 and reduced the risk of vertebral fracture.105 Of concern, the study failed to show a significant reduction in nonvertebral fractures. Although the compound may be well tolerated by many postmenopausal women and appears to reduce the risk of estrogen receptor breast cancer in women with osteoporosis, it can increase the chances of hot flashes and leg cramps, and has a similar increase in the risk of venous thromboembolism as estrogen therapy.100 Bisphosphonates
Bisphosphonates have been used to treat osteoporosis for more than a decade. Originating from pyrophosphates used to remove scale from calcified industrial pipes and plaque from teeth, these antiresorptive drugs are the most widely prescribed class of compounds for the treatment of osteoporosis in the United States.106 Recent large randomized trials have clearly shown that both alendronate (Fosamax) and risedronate (Actonel) maintain or improve BMD, reduce markers of bone turnover,107,108 and significantly reduce the risk of vertebral, nonvertebral, and hip fracture.81,82,84,109–112 Both alendronate and risedronate have been shown, in large well-designed trials, to preserve BMD and to significantly reduce the risk of fractures in glucocorticoid-induced osteoporosis, with risedronate having FDA approval for the prevention of glucocorticoid-induced osteoporosis.112,113 Alendronate appears to have a significant post-treatment suppression of bone turnover.114 One can envision that this may be a significant advantage if it can be shown that a significant antifracture effect persists and that this could be achieved with drug holidays with potentially significant savings to patients. Taking such a compound after menopause for several years may thus be all that is needed to prevent fractures for a significant amount of time in the future. Alternatively, if there are significant benefits to treatment with anabolic agents over bisphosphonates, if prolonged suppression of skeletal turnover may blunt potential benefits from therapy, or if significant long-term side effects emerge, persistent drug effects may be very problematic. So far 10 years of treatment appears to be safe, but clearly further studies are needed to provide definitive answers to these questions and more. Alendronate may have greater potential for upper gastrointestinal adverse events than risedronate115 (which may be better tolerated in people who are otherwise intolerant of other bisphosphonates).116 Both medications are available in several
doses and dosing schedules: alendronate tablets are available in 5 mg and 10 mg daily and 35 mg and 70 mg weekly dosing preparations, and an oral liquid preparation. Risedronate is available in a 5-mg daily tablet and a once-weekly 35-mg tablet. Bisphosphonates should be taken on an empty stomach 30 to 40 minutes before ingestion of food, liquids other than water, or other medications to maximize their poor oral absorption. Patients should be instructed to take the medication with 6 to 8 ounces of plain tap water and to remain in an upright position for at least 60 minutes after taking the medication to decrease the chances of pill esophagitis.92,117 Several other bisphosphonates are available in the United States. Etidronate was the first commercially available bisphosphonate and has been shown to preserve BMD and reduce the risk of fracture118 but is still not approved by the U.S. FDA for treatment of osteoporosis.119 The usual dose is two 200-mg tablets to be taken for 14 days every 3 months. Given its narrow therapeutic index, the cumbersome nature of having to remember this regimen, and the advent of newer, more potent, second- and third-generation bisphosphonates, etidronate use has largely been surpassed. In 2003, ibandronate received FDA approval for the treatment of osteoporosis at an oral dose of 2.5 mg daily. It produces favorable BMD and biochemical marker changes and reduces the risk of vertebral fractures but thus far has not been shown to reduce the risk of nonvertebral fractures.120 Intravenous zoledronic acid, at varying doses and dosage intervals, has been shown to markedly reduce bone turnover markers and produces similar increases in BMD as other bisphosphonates in postmenopausal women.121 Although zoledronic acid is presently only approved for treatment of bone metastases, some preliminary work shows that it might be a useful alternative in patients who cannot otherwise tolerate oral bisphosphonates122; however, reports of maxillary osteonecrosis associated with regular use are a source of concern. Similarly intravenous pamidronate infusions have been shown to have similar efficacy in reducing markers of bone turnover and maintaining or improving BMD in patients with osteoporosis as other bisphosphonates.123,124 Calcitonin
Calcitonin is FDA approved for the treatment of postmenopausal osteoporosis in women. Older preparations of calcitonin derived from salmon and injected subcutaneously often resulted in local hypersensitivity reactions and sometimes antibody formation to the protein, making this a less favorable approach. In 1995, the recombinant form of calcitonin received approval as a nasal spray. Results of a large randomized trial, the PROOF study, have since been published with disappointing results. The attrition rate during the trial was large, and only the 200 IU dose produced a statistically significant reduction in vertebral fractures. There was no significant decrease in nonvertebral fractures.125 Parathyroid Hormone
Parathyroid hormone preparations are an exciting class of compounds and the main class of anabolic agents currently available for treatment of osteoporosis. Only the 1-34 truncated version of teriparatide (Forteo) is FDA approved. In 2002, it was approved for the treatment of postmenopausal osteoporosis (and in men with primary or hypogonadal osteoporosis).91 A large clinical trial showed that individuals who had an average of
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Section 3 Adult Reproductive Endocrinology 18 months of therapy with either 20 or 40 μg of teriparatide by daily subcutaneous injection had significant increases in their BMD, significant increases in levels of biochemical markers of bone turnover, and significant reductions in the incidence of both vertebral and nonvertebral fractures.126 Parathyroid hormone has also been shown to prevent bone loss associated with GnRH antagonist use.101 Side effects include injection site reactions and mild transient hypercalcemia. Patients need to be cautioned about the significant increase in the risk of osteosarcoma in rats treated with high doses of teriparatide for long periods, although it is not clear how this risk pertains to humans at this time.91 Reports of osteosarcoma in subjects with chronic hyperparathyroidism are exceedingly rare, with only four cases reported in the literature.127 The cost of teriparatide for only 1 month is equivalent to the cost of 2 years of estrogen therapy. The use of teriparatide, therefore, should be reserved for individuals with more established disease or for those who do not tolerate other therapies until more long-term data is available.
Combination Therapy
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Combination therapy is an intriguing option for osteoporosis. Although combination therapies have shown promise with greater changes in BMD and bone turnover markers in some trials, no large published clinical trial to date has shown any combination to have a significant fracture reduction over monotherapy.54,128 A therapeutic protocol that decreases bone loss and increases bone formation would be ideal and may be possible with combinations of testosterone and estrogen.129 Addition of androgens to estrogen therapy in women may have more favorable skeletal responses than estrogen alone.129,130 Precisely which combination would be most beneficial in treating persons with hypogonadal bone loss remains unclear at this time, and larger, long-term studies need to be done. Estrogen combined with alendronate and estrogen combined with risedronate have additive reductions in bone turnover markers, with improved BMD changes compared to either agent alone.107 What has become an intriguing question is in what combinations and what sequence these medications should be prescribed and the need for evaluation, although in general combination therapy is discouraged based on expense. Some studies show that there may be a delay or blunting of the anabolic effects of parathyroid hormone in individuals who were pretreated with alendronate.93,101 The clinical significance of this remains unclear at this time. However, it may be prudent to use teriparatide first, based on this preliminary evidence, followed by an oral bisphosphonate. Unpublished and small published trials data show that estrogen or raloxifene may be successfully combined with teriparatide with no blunting of the anabolic effects. Future studies may provide more definitive answers to which combination should be used and how and whether they should be used at all. In general combination therapy is discouraged based on expense and the lack of fracture data. Although there are very few studies in the literature that have sufficient power to compare different compounds in head-to-head trials for reduction of fractures, estrogen and some bisphosphonates that have been shown in large trials to reduce the risk of vertebral, nonvertebral, and hip fractures should be used for established
disease. Whether other therapies can reduce the risk of future nonvertebral or hip fracture remains unclear. Precise treatment protocols for persons who have a low risk of future fracture or currently have low risk but increased long-term risk need further study and clarification. Several novel therapies for osteoporosis are presently being evaluated. Although high-dose statins have been shown to have significant anabolic skeletal effects in laboratory animals,131 they have not been shown to improve BMD or decrease fracture risk in humans at usual oral doses.132 A recent randomized, placebo-controlled trial with simvastatin in postmenopausal women failed to show significant effects on BMD or markers of bone turnover.133 A recent large trial showed that daily oral strontium increases BMD, decreases bone resorption, and increases bone formation, making it the first “dual-action” compound, and reduced by half the risk of vertebral fracture in postmenopausal women.134 Recent trials on human subjects with low bone mass show significant promise with a recombinant injectable form of OPG [results reported at American Society of Bone and Mineral Research—ASBMR, Minneapolis 2003]. Although fluoride was once considered a promising anabolic agent that significantly increased BMD,135 more recent studies show that despite significant changes in bone mass, there was no fracture benefit and possibly even an increase in fractures, in subjects treated with fluoride and calcium compared to placebo.136
Treatment of Glucocorticoid-induced Osteoporosis Given the high risk of fracture in individuals taking glucocorticoid therapy, this subgroup is worthy of special mention here. For the treatment of glucocorticoid-induced osteoporosis, the American College of Rheumatology recommends usual osteoporosis measures, such as lifestyle changes and calcium and vitamin D supplementation. In addition, it is recommended that bisphosphonate therapy be instituted if a patient is starting therapy with prednisone that is expected to be at a dose of greater than 5 mg daily for longer than 3 months. For patients who are already receiving long-term therapy, they recommend similar measures and institution of a bisphosphonate if the patient has a low T-score (< −1.0). Again caution is advised with the use of bisphosphonates in premenopausal women based on pregnancy and fetal concerns. Because many patients receiving chronic glucocorticoids may become hypogonadal, evaluation and hormonal replacement if deficient is also recommended. Calcitonin may be used in individuals intolerant of bisphosphonate therapy.63
Patient Monitoring Despite numerous trials showing the efficacy of these treatments, studies show that greater than 50% of patients who are prescribed osteoporosis therapy do not fill their first prescription and of those who do, many discontinue them within the first year.137 Regular follow-up coupled with testing of biochemical markers of bone turnover may be useful interventions to improve adherence.138 Changes in bone turnover markers seen with osteoporosis therapy occur early with antiremodeling therapy,108 but may be slower for SERMs,85 and may explain a greater part of the fracture risk reduction with therapy than changes in BMD.85,108,139 However, given the significant variability in assays,
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Chapter 25 Osteoporosis they cannot be recommended as the sole means of monitoring patients today. Follow-up BMD testing should be performed at regular intervals every 2 years to make sure that there is no further bone loss. It is important to understand the concept of least significant change when monitoring therapy with BMD testing. This is a measure, calibrated regularly for each individual DXA machine, a change greater than which is clinically significant. Although this usually is approximately 3% in the best centers, it is extremely important to note that this may vary considerably between skeletal sites, machines, and technicians and can only be accurately assessed by performing the necessary calibration for each individual BMD machine and center.140 Knowing the least significant change is important when interpreting serial bone density scans. Annual rates of bone loss in untreated postmenopausal women vary between 0.6% to 1.7% but may be as high as 4%.86 Because different agents have differential skeletal effects that may vary by skeletal site, it is important to note the length of time that a specific therapy is likely to be required before a significant change is seen. For example, if a drug averages a 5% increase in BMD at the spine and 2% at the hip at 1 year and the least significant change for those sites is 2% and 3%, respectively, therapy is unlikely to show a significant change in measured hip BMD after 1 year. In general, greater BMD changes are seen at the lumbar spine, the annual rate of change may vary, and the rate of change depends both on the treatment being used and site being measured. Other risk factors for bone loss and variation between individuals can also affect the rate of BMD change. Parathyroid hormone preparations have shown the greatest annual gains in BMD (2% to 5% at the hip and 5% to 10% at the spine) followed by estrogen or bisphosphonates (1% to 4% at the hip, 2% to 5% at the lumbar spine) followed by raloxifene (0 to 1% at the hip and 0.5% to 2% at the spine).51,81,82,84,95,101,105,107,109,112,126 Stabilization or gain of bone mass is considered a therapeutic success. The magnitude of BMD gain does not explain all the fracture risk reductions. If there is significant loss of bone mass on therapy, adherence should be reviewed, and this may also be an indication to consider other secondary causes of low bone mass.69
Investigational Treatment Approaches Phytoestrogens
Phytoestrogens are naturally occurring compounds that have estrogen-like activity. Many are derivatives of soy protein products, may be even more potent than currently available estrogen
preparations or SERMs, and are currently under scrutiny and intense investigation. Two recently published randomized trials using isoflavone treatment in postmenopausal women revealed conflicting results for significant BMD changes after 1 year of therapy.141,142 Longer treatment periods may be needed to see significant differences in BMD with certain treatments. Dehydroepiandrosterone
Dehydroepiandrosterone (DHEA), currently available over the counter in the United States, may have potential, showing preservation of BMD in treated patients with systemic lupus erythematosus.143 The addition of DHEA to other treatments is under investigation.144 Growth Hormone
Growth hormone preparations also appear promising in some studies.145 Lastly, several small trials have shown favorable results of long-term treatment with the SERM tibolone as an estrogen alternative.146,147 However, until large rigorous scientific trials show that specific compounds are safe and effectively reduce vertebral and nonvertebral fracture risk, patients should not be advised to consider their use for the treatment or prevention of osteoporosis.
PEARLS ●
●
●
●
●
●
●
Osteoporosis is common, the incidence is increasing, and a significant percentage of women sustain fragility fractures. Women with established osteoporosis are often not diagnosed or treated for their disease. The diagnosis can be made by history of a fragility fracture and/or BMD testing in the appropriate setting. There are many effective therapeutic options, with estrogen being the only agent shown to reduce all types of fractures in the nonosteoporotic population. Women who are being evaluated and treated for their disease should undergo a careful evaluation for potential risk factors or other causes of low bone mass and should have careful follow-up to monitor effectiveness of therapy, which may include bone turnover markers. Nonadherence limits the effectiveness of therapeutic interventions, and women should be followed up regularly. Women with unusual features or difficult to treat disease warrant referrals to physicians specializing in metabolic bone disease.
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30. Bainbridge KE, Sowers M, Lin X, Harlow SD: Risk factors for low bone mineral density and the 6-year rate of bone loss among premenopausal and perimenopausal women. Osteoporos Int 15:439–446, 2004. 31. Laitinen KD, Valimaki M: Alcohol and bone. Calcif Tissue Int 49(Suppl):S70–S73, 1991. 32. Lewiecki EM, Watts NB, McClung MR, et al: Official positions of the International Society for Clinical Densitometry. J Clin Endocrinol Metab 89:3651–3655, 2004. 33. Kimble RB, Bain S, Pacifici R: The functional block of TNF but not of IL-6 prevents bone loss in ovariectomized mice. J Bone Miner Res 12:935–941, 1997. 34. Ralston SH, Russell RG, Gowen M: Estrogen inhibits release of tumor necrosis factor from peripheral blood mononuclear cells in postmenopausal women. J Bone Miner Res 5:983–988, 1990. 35. Ralston SH: Analysis of gene expression in human bone biopsies by polymerase chain reaction: Evidence for enhanced cytokine expression in postmenopausal osteoporosis. J Bone Miner Res 9:883–890, 1994. 36. Udagawa N, Takahashi N, Yasuda H, et al: Osteoprotegerin produced by osteoblasts is an important regulator in osteoclast development and function. Endocrinology 141:3478–3484, 2000. 37. Ammann P, Rizzoli R, Bonjour JP, et al: Transgenic mice expressing soluble tumor necrosis factor-receptor are protected against bone loss caused by estrogen deficiency. J Clin Invest 99:1699–1703, 1997. 38. Roggia C, Gao Y, Cenci S, et al: Up-regulation of TNF-producing T cells in the bone marrow: A key mechanism by which estrogen deficiency induces bone loss in vivo. Proc Natl Acad Sci USA 98:13960–13965, 2001. 39. Simonet WS, Lacey DL, Dunstan CR, et al: Osteoprotegerin: A novel secreted protein involved in the regulation of bone density. Cell 89:309–319, 1997. 40. Bucay N, Sarosi I, Dunstan CR, et al: Osteoprotegerin-deficient mice develop early onset osteoporosis and arterial calcification. Genes Dev 12:1260–1268, 1998. 41. Schett G, Redlich K, Hayer S, et al: Osteoprotegerin protects against generalized bone loss in tumor necrosis factor-transgenic mice. Arthritis Rheum 48:2042–2051, 2003. 42. Wiren KM: Androgen action in bone: Basic cellular and molecular aspects. In Orwoll ES, Bliziotes M (ed): Osteoporosis: Pathophysiology and Clinical Management. Totowa, N.J., Humana Press, 2002, pp 349–374. 43. Goulding A, Gold E. Flutamide-mediated androgen blockade evokes osteopenia in the female rat. J Bone Miner Res 8:763–769, 1993. 44. Smith MR, McGovern FJ, Zietman AL, et al: Pamidronate to prevent bone loss during androgen-deprivation therapy for prostate cancer. NEJM 345:948–955, 2001. 45. Carlin AJ, Farquharson RG, Quenby SM,et al: Prospective observational study of bone mineral density during pregnancy: Low molecular weight heparin versus control. Hum Reprod 19:1211–1214, 2004. 46. Pearson D, Kaur M, San P, et al: Recovery of pregnancy mediated bone loss during lactation. Bone 34:570–578, 2004. 47. Dempster DW: Bone microarchitecture and strength. Osteoporos Int 14(Suppl 5):54–56, 2003. 48. Rogers A, Hannon RA, Eastell R: Biochemical markers as predictors of rates of bone loss after menopause. J Bone Miner Res 15:1398–1404, 2000. 49. Garnero P, Sornay-Rendu E, Duboeuf F, Delmas PD: Markers of bone turnover predict postmenopausal forearm bone loss over 4 years: The OFELY study. J Bone Miner Res 14:1614–1621, 1999. 50. Garnero P, Sornay-Rendu E, Claustrat B, Delmas PD: Biochemical markers of bone turnover, endogenous hormones and the risk of fractures in postmenopausal women: The OFELY study. J Bone Miner Res 15:1526–1536, 2000. 51. Sornay-Rendu E, Garnero P, Munoz F, et al: Effect of withdrawal of hormone replacement therapy on bone mass and bone turnover: The OFELY study. Bone 33:159–166, 2003. 52. Holick MF: Sunlight and vitamin D for bone health and prevention of autoimmune diseases, cancers, and cardiovascular disease. Am J Clin Nutr 80:1678S–1688S, 2004.
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76. Chantler IW, Davie MW, Evans SF, Rees JS: Oral corticosteroid prescribing in women over 50, use of fracture prevention therapy, and bone densitometry service. Ann Rheum Dis 62:350–352, 2003. 77. Devine A, Dhaliwal SS, Dick IM, et al: Physical activity and calcium consumption are important determinants of lower limb bone mass in older women. J Bone Miner Res 19:1634–1639, 2004. 78. Augestad LB, Schei B, Forsmo S, Et al: The association between physical activity and forearm bone mineral density in healthy premenopausal women. J Womens Health (Larchmt) 13:301–313, 2004. 79. Gerdhem P, Obrant KJ: Effects of cigarette-smoking on bone mass as assessed by dual-energy X-ray absorptiometry and ultrasound. Osteoporos Int 13:932–936, 2002. 80. Oncken C, Prestwood K, Cooney JL, et al: Effects of smoking cessation or reduction on hormone profiles and bone turnover in postmenopausal women. Nicotine Tob Res 4:451–458, 2002. 81. McClung MR, Geusens P, Miller PD, et al: Effect of risedronate on the risk of hip fracture in elderly women. Hip Intervention Program Study Group. NEJM 344:333–340, 2001. 82. Heaney RP, Zizic TM, Fogelman I, et al: Risedronate reduces the risk of first vertebral fracture in osteoporotic women. Osteoporos Int 13:501–505, 2002. 83. Chapuy MC, Pamphile R, Paris E, et al: Combined calcium and vitamin D3 supplementation in elderly women: Confirmation of reversal of secondary hyperparathyroidism and hip fracture risk: The Decalyos II study. Osteoporos Int 13:257–264, 2002. 84. Harris ST, Watts NB, Genant HK, et al: Effects of risedronate treatment on vertebral and nonvertebral fractures in women with postmenopausal osteoporosis: A randomized controlled trial. Vertebral Efficacy With Risedronate Therapy (VERT) Study Group. JAMA 282:1344–1352, 1999. 85. Bjarnason NH, Sarkar S, Duong T, et al: Six and twelve month changes in bone turnover are related to reduction in vertebral fracture risk during 3 years of raloxifene treatment in postmenopausal osteoporosis. Osteoporos Int 12:922–930, 2001. 86. Chapuy MC, Arlot ME, Duboeuf F, et al: Vitamin D3 and calcium to prevent hip fractures in the elderly women. NEJM 327:1637–1642, 1992. 87. Bischoff HA, Stahelin HB, Dick W, et al: Effects of vitamin D and calcium supplementation on falls: A randomized controlled trial. J Bone Miner Res 18:343–351, 2003. 88. American College of Obstetricians and Gynecologists (ACOG): Osteoporosis. ACOG Pract Bull 50:203–216, 2004. 89. Anderson GL, Limacher M, Assaf AR, et al: Effects of conjugated equine estrogen in postmenopausal women with hysterectomy: The Women’s Health Initiative randomized controlled trial. JAMA 291:1701–1712, 2004. 90. Rossouw JE, Anderson GL, Prentice RL, et al: Risks and benefits of estrogen plus progestin in healthy postmenopausal women: Principal results from the Women’s Health Initiative randomized controlled trial. JAMA 288:321–333, 2002. 91. Eli Lilly Pharmaceuticals Forteo Product Information. 2002. Available at http://www.rxlist.com/cgi/rxlist.cgi?drug=forteo. Accessed 22 September 2004. 92. Procter & Gamble Pharmaceuticals: Actonel Drug Information. 2000. Available at http://www.rxlist.com/cgi/rxlist.cgi?drug=actonel. Accessed 22 September 2004. 93. Black DM, Greenspan SL, Ensrud KE, et al: The effects of parathyroid hormone and alendronate alone or in combination in postmenopausal osteoporosis. NEJM 349:1207–1215, 2003. 94. Thacker HL: The case for hormone replacement: New studies that should inform the debate. Cleve Clin J Med 69:670–678, 2002. 95. Lindsay R: The role of estrogen in the prevention of osteoporosis. Endocrinol Metab Clin North Am 27:399–409, 1998. 96. Marcus R, Holloway L, Wells B, et al: The relationship of biochemical markers of bone turnover to bone density changes in postmenopausal women: Results from the Postmenopausal Estrogen/Progestin Interventions (PEPI) trial. J Bone Miner Res 14:1583–1595, 1999. 97. Kothari S, Thacker HL: Risk assessment of the menopausal patient. Med Clin North Am 83:1489–1502, 1999.
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98. Lufkin EG, Wahner HW, O’Fallon WM, et al: Treatment of postmenopausal osteoporosis with transdermal estrogen. Ann Intern Med 117:1–9, 1992. 99. Nelson HD, Rizzo J, Harris E, et al: Osteoporosis and fractures in postmenopausal women using estrogen. Arch Intern Med 162:2278–2284, 2002. 100. Delmas PD, Ensrud KE, Adachi JD, et al: Efficacy of raloxifene on vertebral fracture risk reduction in postmenopausal women with osteoporosis: Four-year results from a randomized clinical trial. J Clin Endocrinol Metab 87:3609–3617, 2002. 101. Finkelstein JS, Hayes A, Hunzelman JL, et al: The effects of parathyroid hormone, alendronate, or both in men with osteoporosis. NEJM 349:1216–1226, 2003. 102. Smith A: The female athlete triad: Causes, diagnosis and treatment. Phys Sportsmed 24:67–86, 1996. 103. Erickson SM: Osteoporosis in active women: Prevention, diagnosis and treatment. Phys Sportsmed 25:61–74, 1997. 104. Miller KK. Mechanisms by which nutritional disorders cause reduced bone mass in adults. J Womens Health (Larchmt) 12:145–150, 2003. 105. Greendale GA, Espeland M, Slone S, et al: Bone mass response to discontinuation of long-term hormone replacement therapy: Results from the Postmenopausal Estrogen/Progestin Interventions (PEPI) Safety Follow-up Study. Arch Intern Med 162:665–672, 2002. 106. Fleisch H: Bisphosphonates in Bone Disease: From the Laboratory to the Patient, 4th ed. San Diego, Academic Press, 2000. 107. Greenspan SL, Emkey RD, Bone HG, et al: Significant differential effects of alendronate, estrogen, or combination therapy on the rate of bone loss after discontinuation of treatment of postmenopausal osteoporosis. A randomized, double-blind, placebo-controlled trial. Ann Intern Med 137:875–883, 2002. 108. Eastell R, Barton I, Hannon RA, et al: Relationship of early changes in bone resorption to the reduction in fracture risk with risedronate. J Bone Miner Res 18:1051–1056, 2003. 109. Reginster J, Minne HW, Sorensen OH, et al: Randomized trial of the effects of risedronate on vertebral fractures in women with established postmenopausal osteoporosis. Vertebral Efficacy with Risedronate Therapy (VERT) Study Group. Osteoporos Int 11:83–91, 2000. 110. Black DM, Cummings SR, Karpf DB, et al: Randomised trial of effect of alendronate on risk of fracture in women with existing vertebral fractures. Fracture Intervention Trial Research Group. Lancet 348:1535–1541, 1996. 111. Cummings SR, Black DM, Thompson DE, et al: Effect of alendronate on risk of fracture in women with low bone density but without vertebral fractures: Results from the Fracture Intervention Trial. JAMA 280:2077–2082, 1998. 112. Wallach S, Cohen S, Reid DM, et al: Effects of risedronate treatment on bone density and vertebral fracture in patients on corticosteroid therapy. Calcif Tissue Int 67:277–285, 2000. 113. Saag KG, Emkey R, Schnitzer TJ, et al: Alendronate for the prevention and treatment of glucocorticoid-induced osteoporosis. GlucocorticoidInduced Osteoporosis Intervention Study Group. NEJM 339:292–299, 1998. 114. Bone HG, Hosking D, Devogelaer JP, et al: Ten years’ experience with alendronate for osteoporosis in postmenopausal women. NEJM 350:1189–1199, 2004. 115. Lanza FL, Hunt RH, Thomson AB, et al: Endoscopic comparison of esophageal and gastroduodenal effects of risedronate and alendronate in postmenopausal women. Gastroenterology 119:631–638, 2000. 116. Delaney MF, Hurwitz S, Shaw J, LeBoff MS: Bone density changes with once weekly risedronate in postmenopausal women. J Clin Densitom 6:45–50, 2003. 117. Merck & Co: Fosamax Product Information. Available at: http://www. drugs.com/fosamax.html. Accessed 22 September 2004. 118. Miller PD, Watts NB, Licata AA, et al: Cyclical etidronate in the treatment of postmenopausal osteoporosis: Efficacy and safety after seven years of treatment. Am J Med 103:468–476, 1997. 119. Procter & Gamble Pharmaceuticals: Didronel: Drug Information. 2004. Available at: http://www.rxlist.com/cgi/pharmclips2.cgi?keyword =%20%20Didronel%20%AE%20. Accessed 21 September 2004.
120. Stakkestad JA, Benevolenskaya LI, Stepan JJ, et al: Intravenous ibandronate injections given every three months: A new treatment option to prevent bone loss in postmenopausal women. Ann Rheum Dis 62:969–975, 2003. 121. Reid IR, Brown JP, Burckhardt P, et al: Intravenous zoledronic acid in postmenopausal women with low bone mineral density. NEJM 346:653–661, 2002. 122. Mikulec KH, Delaney MF, Hurwitz S, LeBoff MS: Safety and efficacy of zoledronic acid: A chart review. J Bone Miner Res Suppl. M321, 2003. 123. Chan SS, Nery LM, McElduff A, et al: Intravenous pamidronate in the treatment and prevention of osteoporosis. Intern Med J 34:162–166, 2004. 124. Voskaridou E, Terpos E, Spina G, et al: Pamidronate is an effective treatment for osteoporosis in patients with beta-thalassaemia. Br J Haematol 123:730–737, 2003. 125. Chesnut CH 3rd, Silverman S, Andriano K, et al: A randomized trial of nasal spray salmon calcitonin in postmenopausal women with established osteoporosis: The prevent recurrence of osteoporotic fractures study. PROOF Study Group. Am J Med 109:267–276, 2000. 126. Neer RM, Arnaud CD, Zanchetta JR, et al: Effect of parathyroid hormone (1-34) on fractures and bone mineral density in postmenopausal women with osteoporosis. NEJM 344:1434–1441, 2001. 127. Jutte PC, Rosso R, de Paolis M, et al: Osteosarcoma associated with hyperparathyroidism. Skeletal Radiol 33:473–476, 2004. 128. Fadanelli ME, Bone HG: Combining bisphosphonates with hormone therapy for postmenopausal osteoporosis. Treat Endocrinol 3:361–369, 2004. 129. Raisz LG, Wiita B, Artis A, et al: Comparison of the effects of estrogen alone and estrogen plus androgen on biochemical markers of bone formation and resorption in postmenopausal women. J Clin Endocrinol Metab 81:37–43, 1996. 130. Watts NB, Notelovitz M, Timmons MC, et al: Comparison of oral estrogens and estrogens plus androgen on bone mineral density, menopausal symptoms, and lipid–lipoprotein profiles in surgical menopause. Obstet Gynecol 85:529–537, 1995. 131. Garrett IR, Mundy GR: The role of statins as potential targets for bone formation. Arthritis Res 4:237–240, 2002. 132. LaCroix AZ, Cauley JA, Pettinger M, et al: Statin use, clinical fracture, and bone density in postmenopausal women: Results from the Women’s Health Initiative Observational Study. Ann Intern Med 139:97–104, 2003. 133. Rejnmark L, Buus NH, Vestergaard P, et al: Effects of simvastatin on bone turnover and BMD: A 1-year randomized controlled trial in postmenopausal osteopenic women. J Bone Miner Res 19:737–744, 2004. 134. Meunier PJ, Roux C, Seeman E, et al: The effects of strontium ranelate on the risk of vertebral fracture in women with postmenopausal osteoporosis. NEJM 350:459–468, 2004. 135. Riggs BL, Seeman E, Hodgson SF, et al: Effect of the fluoride/calcium regimen on vertebral fracture occurrence in postmenopausal osteoporosis. Comparison with conventional therapy. NEJM 306:446–450, 1982. 136. Riggs BL, Hodgson SF, O’Fallon WM, et al: Effect of fluoride treatment on the fracture rate in postmenopausal women with osteoporosis. NEJM 322:802–809, 1990. 137. McCombs JS, Thiebaud P, McLaughlin-Miley C, Shi J: Compliance with drug therapies for the treatment and prevention of osteoporosis. Maturitas 48:271–287, 2004. 138. Clowes JA, Peel NF, Eastell R: The impact of monitoring on adherence and persistence with antiresorptive treatment for postmenopausal osteoporosis: A randomized controlled trial. J Clin Endocrinol Metab 89:1117–1123, 2004. 139. Greenspan SL, Parker RA, Ferguson L, et al: Early changes in biochemical markers of bone turnover predict the long-term response to alendronate therapy in representative elderly women: A randomized clinical trial. J Bone Miner Res 13:1431–1438, 1998. 140. Lenchik L, Kiebzak GM, Blunt BA: What is the role of serial bone mineral density measurements in patient management? J Clin Densitom 5(Suppl):S29–S38, 2002.
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Chapter 25 Osteoporosis 141. Kreijkamp-Kaspers S, Kok L, Grobbee DE, et al: Effect of soy protein containing isoflavones on cognitive function, bone mineral density, and plasma lipids in postmenopausal women: A randomized controlled trial. JAMA 292:65–74, 2004. 142. Chen YM, Ho SC, Lam SS, et al: Beneficial effect of soy isoflavones on bone mineral content was modified by years since menopause, body weight, and calcium intake: A double-blind, randomized, controlled trial. Menopause 11:246–254, 2004. 143. van Vollenhoven RF: Dehydroepiandrosterone in systemic lupus erythematosus. Rheum Dis Clin North Am 26:349–362, 2000. 144. Delaney MF, Hurwitz S, Chan CK, Leboff MS: Combination therapy with micronized dehydroepiandrosterone and raloxifene or placebo:
Changes in markers of bone turnover. J Bone Miner Res 18:M364, 2003. 145. Biermasz NR, Hamdy NA, Pereira AM, et al: Long-term skeletal effects of recombinant human growth hormone (rhGH) alone and rhGH combined with alendronate in GH-deficient adults: A seven-year follow-up study. Clin Endocrinol (Oxf) 60:568-575, 2004. 146. Rymer J, Robinson J, Fogelman I: Ten years of treatment with tibolone 2.5 mg daily: Effects on bone loss in postmenopausal women. Climacteric 5:390-398, 2002. 147. Prelevic GM, Markou A, Arnold A, et al: The effect of tibolone on bone mineral density in postmenopausal women with osteopenia or osteoporosis–8 years follow-up. Maturitas 47:229-234, 2004.
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Section 4 Contraception Chapter
26
Hormonal Contraception Ronald T. Burkman
INTRODUCTION Hormonal contraception methods have allowed women to gain control of their reproductive function. As a result, these methods have become both a significant change agent and a major pharmacologic healthcare intervention. Today, hormonal contraception methods are used by approximately 10 million women in the United States and by more than 90 million women worldwide. Oral contraceptive pills, the most commonly used type of hormonal contraception, have been available in the United States for over 40 years. Their popularity is due to their low failure rate, ease of use, reversibility, and noncontraceptive benefits. However, substantial contraceptive challenges still remain. Despite the continued development of effective contraceptive methods and increased educational efforts, unintended pregnancies continue to be a major problem in the United States. According to the National Survey of Family Growth, half of a total of 6.3 million pregnancies in the United States in 1994 were unintended, and 1 million of these pregnancies occurred while using oral contraceptives.1,2 Clearly, the need remains for development of improved contraceptive methods. This chapter begins with a brief look at the history of oral contraceptives. Following this, each type of currently available hormonal contraception is described in terms of formulations, mechanism of action, efficacy and benefits, and risks and side effects.
HISTORY The history of the development of “the pill” is fascinating. At the turn of the 20th century, an Austrian professor of physiology, Ludwig Haberlandt, demonstrated that pregnancy could be prevented in mice by giving them oral extracts from mice ovaries.3 In the 1940s, Dr. Carl Djerassi, working for the pharmaceutical company Syntex, discovered that the removal of the 19 carbon from yam-derived progesterone increased its progestational activity. This discovery led to the synthesis of norethindrone, an orally active progestin, in 1951.3,4
Dr. Pincus Dr. Gregory Pincus is commonly referred to as the father of the pill. After making national headlines in 1934 by achieving in vitro fertilization of rabbit oocytes, he found that the world was not ready for this technology. He thus shifted his attention from
mammalian fertilization to oral contraception for women and received a grant from the Planned Parenthood Federation in 1951 to find a progestin that could be used as an oral contraceptive agent. After evaluating hundreds of substances, Pincus found two steroid compounds derived from the roots of the wild Mexican yam that could inhibit ovulation in laboratory animals. Pharmaceutical companies refined and advanced these discoveries to extract progestins and estrogens from plant material. Of interest, Pincus and his colleagues devoted a great deal of time and energy to purify the progestin norethynodrel from its estrogen contaminant mestranol. However, they subsequently discovered that mestranol could reduce breakthrough bleeding and acted synergistically with progestins to enhance contraceptive efficacy. In 1956, Pincus, working in conjunction with the G.D. Searle Pharmaceutical Company and Dr. John Rock, conducted field tests of a hormonal contraceptive pill with hundreds of women in Massachusetts, Puerto Rico, and Haiti. They demonstrated that oral steroid hormones could be effective contraception, with side effects limited primarily to nausea. The U.S. Food and Drug Administration (FDA) authorized the production of contraceptive pills for limited use in 1957. Three years later, the FDA licensed G.D. Searle to produce the first commercially available oral contraceptive, Enovid, which contained 150 μg of mestranol and 9.85 mg norethynodrel. Soon after the introduction of Enovid, other manufacturers introduced additional oral contraceptive formulations.
Modern Hormonal Contraceptives Since the introduction of oral contraceptives more than 40 years ago, the hormone dosage used has been reduced by as much as eightfold. More recently, multiple new estrogens and progestins and several different delivery systems have been utilized in an effort to increase effectiveness, compliance, and continuation rates. A broad range of contraceptive hormones and delivery systems are presently available in the United States today (Table 26-1). Several of the newer hormonal delivery systems are parenteral, and some of the preparations no longer need to be taken daily. The most frequently used and best studied are the combination oral contraceptives that contain a synthetic estrogen and one of several progestins. Three progestin-only oral contraceptives are currently available. In addition, a vaginal patch, a vaginal ring, a single rod implant, and an injectable medroxyprogesterone are commercially available.
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Section 4 Contraception ORAL CONTRACEPTIVES Patient Selection Oral contraceptives are an excellent contraceptive choice for many patients who are willing and able to consistently take a daily pill. In some cases, oral contraceptives may be recommended to patients because of their noncontraceptive benefits, such as treatment of dysmenorrhea or acne. The vast majority of healthy women can take oral contraceptives with an extremely low risk of serious side effects or risks. However, there are several standard contraindications to use of hormonal contraceptive methods that contain estrogen (Table 26-2). Many of these women are good candidates for progestin-only contraceptives. The remainder should be counseled to use an alternative nonhormonal method.
found an association between the estrogen content of early oral contraceptives and venous thromboembolism, researchers found that the estrogen component could be significantly reduced with no loss of contraceptive efficacy. As a result, most modern oral contraceptive pills now contain between 25 and 35 μg of ethinyl estradiol, and a few contain as little as 20 μg.5 Although reducing the daily estrogen dose to either 30 or 35 μg has been shown to reduce the risk of venous thromboembolism, no study has shown that further decreasing the estrogen dose reduces the risk further. Progestins
The prototype progestin used in modern oral contraceptive pills is norethindrone (an estrane), which is created from progesterone by adding both a 19-carbon methyl group and a 17-α ethinyl group similar to ethinyl estradiol (Fig. 26-2). Norgestrel (a
Estrogens and Progestins Estrogens
Combination oral contraceptive pills contain one of two synthetic estrogens: ethinyl estradiol or, less commonly, mestranol. Both of these steroids are created by adding a 17-α ethinyl group to estradiol to increase potency and enhance oral activity by impeding hepatic degradation (Fig. 26-1). Natural estrogens are relatively weak when given by mouth due to their rapid clearance from blood by the liver (i.e., the first-pass effect). As a result of decreased degradation, both of these synthetic estrogens are 10 to 20 times more active than estradiol when given orally, but have similar potency when given intravenously. The original formulation for oral contraceptive pills contained as much as 150 μg of synthetic estrogen each. When studies Table 26-1 Formulations of Some Modern Hormonal Contraceptives Delivery System
Estrogens
Progestins*
Oral contraceptives Combination (constant dose)
Ethinyl estradiol (dose: 20–50 μg) Mestranol (dose: 50 μg)
Estranes: Norethindrone Norethindrone acetate Ethynodiol diacetate Gonanes: Norgestrel Levonorgestrel Norgestimate Desogestrel Gestodene Ethynodiol diacetate
Combination (sequential*)
Ethinyl estradiol (20–40 μg)
Progestin only
Spironolactone analog: Drospirenone Norethindrone Norgestimate Levonorgestrel Desogestrel Norethindrone Norgestrel
Transdermal patch
Ethinyl estradiol
Norelgestromin
Vaginal ring
Ethinyl estradiol
Etonogestrel
Injectable
Medroxyprogesterone acetate (depot form)
Subdermal implant†
Etonorgestrel
Table 26-2 Contraindications to Use of Combination Oral Contraceptives
Contraindication (current or past history) Absolute Contraindications Suspected pregnancy Undiagnosed uterine bleeding Liver disease Symptomatic gall bladder disease Breast cancer Estrogen-induced liver tumor Thromboembolism Cerebral vascular disease Coronary heart disease Estrogen-dependent tumors Seriously impaired liver function
388
Progestinonly
X X X X X X X X X X X
Relative Contraindications Age > 35 years with any cardiovascular risk factors: Cigarette smoking Hypertension Abnormal lipid profile Diabetes mellitus Known cardiovascular disease Severe headaches: vascular or migraine Hypertension Diabetes Gallstones Within 3 weeks of childbirth Breastfeeding (especially first 6 weeks) History of cholestasis of pregnancy Systemic lupus erythematosus Abdominal or lower extremity surgery contemplated within 4–6 weeks Lower leg cast Hypertriglyceridemia Use of drugs that interact with oral contraceptives (e.g., rifampin)
X X X X X
X
X X X X X X X X X
X
X X X X
OH CH3
OH C
CH
O
HO Ethinyl estradiol
*Sequential oral contraceptives have changing doses of estrogens, progestins, or both throughout the cycle.
Combination (estrogencontaining)
Mestranol
Figure 26-1 Synthetic estrogens used in combination oral contraceptives.
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Chapter 26 Hormonal Contraception OH CH3
OH C
CH
O
O Norethindrone
Norgestrel
OH
O
O
O O
O Norethynodrel
Ethynodiol diacetate
CH3 H3C
OH C
H2C
CH2
CH H
OCOCH3 C
CH
H H
H
HON Desogestrel
Norgestimate
O
H3C
H3C
OH C
H2C
CH
H
H3C H O
O
O
H H
H
H H
Etonorgestrel Figure 26-2
Drospirenone
Progestins used in combination and progestin-only oral contraceptives.
gonane) is the 18-carbon-ethyl derivative of norethindrone and is a racemic mixture of dextronorgestrel and levonorgestrel. Levonorgestrel is the biologically active component of norgestrel. Norethynodrel and ethynodiol diacetate are related progestin analogues with longer durations of action. These progestins have a more potent effect on the endometrium than norethindrone, allowing the daily progestin dose to be reduced to between 0.15 and 1 mg. In the 1980s, a number of new progestins were developed such as desogestrel and norgestimate. Desogestrel is a “prodrug” and must be metabolized to its active metabolic component,
etonogestrel. Norgestimate, although active, is primarily metabolized to norelgestromin and small amounts of levonorgestrel. These progestins maintain desired effects on the endometrium, but had reduced androgenic effects, such as acne, weight gain, and undesired effects on lipids and lipoproteins. Today, the most commonly used progestins in oral contraceptives are norgestimate, norethindrone, and norgestrel. Progestin-only pills with no estrogen component are also discussed in this chapter. Recently, drospirenone, a somewhat unique progestin, has been introduced in the United States.6 This anti-androgenic analogue
389
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Section 4 Contraception of spironolactone has a high binding affinity for progesterone and mineralocorticoid receptors, but a low binding affinity for the androgen receptors. Oral contraceptives containing this progestin are associated with less fluid retention but have a slight theoretical risk of hyperkalemia.7 Women with renal insufficiency, hepatic dysfunction, or adrenal insufficiency should not use oral contraceptives containing drospirenone.
COMBINATION ORAL CONTRACEPTIVE PILLS The majority of oral contraceptive pills on the market today contain both an estrogen and progestin in tablets that are taken daily for 21 days out of each 28-day cycle (see Table 26-1). During the remaining 7 days, women are instructed to take either inert pills (to assist the patient in maintaining the daily habit of taking a contraceptive pill) or no pills at all. At least one modern contraceptive pill gives women a lower dose of estrogen alone during 5 of these remaining 7 days. Extended-use oral contraceptives refers to an approach where active combination oral contraceptive pills are taken daily for 84 days followed by a 7-day hormone-free period.
Mechanism of Action Oral contraceptives were originally designed such that progestin would inhibit ovulation by suppressing luteinizing hormone release at the level of the hypothalamus or pituitary. Estrogen was included to stabilize the endometrium to minimize breakthrough bleeding and spotting, although estrogen has been found to help suppress ovulation by inhibiting release of folliclestimulating hormone. Other contraceptive mechanisms of action of oral contraceptive pills have since been discovered. Progestins decrease entry of sperm into the uterus by decreasing sperm motility and increasing cervical mucus viscosity. Progestins also inhibit sperm transport by decreasing fallopian tube motility. Finally, progestins alter the endometrium and thus inhibit implantation.
Efficacy
390
Approximately 7% of women using combination oral contraceptives will have an unintended pregnancy during the first 12 months of use.8 Rates reported in different clinical trials can be highly variable because of factors, including methodology, demographics, various types of bias, and methods of calculating rates.9–12 Two of the most common methods are the Pearl index and life table analysis. The Pearl index is a common method used to compare contraception efficacy. The Pearl index indicates the number of unintentional pregnancies related to 100 women-years of use. To calculate this index, the number of pregnancies that occur during a year are divided by cumulative months of exposure, and the quotient multiplied by 1200. If three pregnancies occur during a year in 100 women, the Pearl index will be 3.0 (i.e., 1200 months × 3 pregnancies/1200). This method is not ideal for comparing rates if studies are of different durations, because pregnancy rates can change over time. Life table analysis is more effective for comparing failure rates than the Pearl index because a separate failure rate is determined for each month of use.12 Life table analysis also allows separate evaluation of both method and user failure rates.
Method failure rates refer to pregnancy rates that occur when the method has been used correctly, in a consistent manner, and according to the instructions in the package insert. User failure rates (i.e., typical failure rates) refer to pregnancies that occur when the method is not used correctly. The reported method failure rates for oral contraceptive pills are between 1% and 3% and user failure rates are approximately 7%.11 Both method and user failure rates are similar for women over age 30 who are in higher socioeconomic groups. In contrast, the user failure rate is much higher for teenagers and unmarried women, sometimes surpassing 30%.
NONCONTRACEPTIVE BENEFITS OF COMBINATION ORAL CONTRACEPTIVES Decreased Risk of Ectopic Pregnancies Combination oral contraceptives reduce the risk of ectopic pregnancy by 90%.13 The likely mechanism is through suppression of ovulation, an effect that obviously prevents all types of pregnancy. In contrast, some studies have indicated that women using progestin-only oral contraceptives are at higher risk for an ectopic pregnancy than the general population.
Decreased Risk of Pelvic Inflammatory Disease Several studies have shown that oral contraceptive use reduces the risk of pelvic inflammatory disease (PID) by 50% to 80% compared to women who use no method or a barrier method for contraception.13–15 However, one recent multicenter study failed to show a protective effect of oral contraceptives.16 Because oral contraceptives do not protect against the acquisition of lower genital tract sexually transmitted diseases (e.g., Chlamydia trachomatis and Neisseria gonorrhoeae), the assumption is that they impede bacterial ascent from the uterine cervix into the upper genital tract. Several possible mechanisms for this have been suggested. Progestins cause cervical mucus to become thick and viscous, and this might substantially inhibit the ascent of bacteria. Alternatively, the reduced menstrual flow resulting from oral contraceptives could decrease retrograde menstrual flow to the fallopian tubes and result in a less favorable environment for promoting bacterial growth. Finally, hormonerelated changes in uterine contractility might make ascent of organisms less likely.
Decreased Risk of Malignancies Endometrial Cancer
Multiple case-control and cohort studies have shown that oral contraceptives protect against endometrial cancer.17–19 The overall reduction in risk is up to 50% and begins 1 year after initiation of use. This protection increases with the duration of use and persists for up to 20 years after oral contraceptives are discontinued. The strength of the protective effect varies according to the existence of other risk factors, such as obesity and nulliparity. The purported protective mechanism of action is a reduction in the mitotic activity of endometrial cells by the action of the progestin component of oral contraceptives.
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Chapter 26 Hormonal Contraception Ovarian Cancer
Multiple case-control and cohort studies have shown that the use of oral contraceptives protects against the development of ovarian cancer.20–22 The overall risk is decreased by 40% to 80%. The effect begins about 1 year after initiating use and decreases by 10% to 12% for each year of use. Protection persists for 15 to 20 years after discontinuation of the oral contraceptives. Several mechanisms have been proposed by which oral contraceptives might reduce ovarian cancer risk. Suppression of ovulation has been hypothesized to reduce the frequency of “injury” to the ovarian capsule that occurs during ovulation. Suppression of gonadotropins by hormonal contraceptives might also play a role. Finally, data from a primate model suggests that hormonal contraceptives can induce ovarian apoptosis, which in turn eliminates surface epithelium inclusion cysts, thus reducing ovarian cancer risk.23 Colorectal Cancer
Multiple studies have demonstrated up to a 40% reduction in colon and rectal cancer among women who have used oral contraceptives.24–26 However, one study did not find a protective effect of oral contraceptives.27 Theoretical protective mechanisms include a reduction in bile acid production and concentration, and effects on colonic mucosa or flora.28
Decreased Menstrual Flow and Dysmenorrhea Up to 75% of young women will experience some degree of dysmenorrhea, and 15% to 20% will have severe pain.29,30 Multiple studies have shown that combination oral contraceptives reduce both menstrual flow and dysmenorrhea.29–34 Two possible mechanisms have been proposed to explain how oral contraceptives reduce dysmenorrhea. Women taking oral contraceptives have been shown to have reduced prostaglandins in the menstrual fluid. It is hypothesized that by decreasing prostaglandin production by the uterus, oral contraceptives decrease dysmenorrhea by decreasing either endometrial vasoconstriction and ischemia or uterine contractile activity.35,36
Decreased Benign Breast Disease Several studies have shown a 30% to 50% decrease in the incidence of benign fibrocystic breast changes in women using oral contraceptives.37,38 One of the clearest effects is a decrease in the occurrence of fibroadenomas among current and recent long-term users of oral contraceptives under age 45. The most likely mechanism is through suppression of ovulation and therefore inhibition of the breast cell proliferation that normally occurs in the first half of an ovulatory menstrual cycle.
risk of symptomatic ovarian cysts. Interestingly, progestin-only oral contraception may actually increase the frequency of functional ovarian cysts, according to one small study.42 Cyst Resolution
Many clinicians prescribe combination oral contraceptives to women found to have an ovarian cyst in an effort to accelerate its spontaneous resolution, presumably by decreasing gonadotropin secretion centrally. However, there are no data to support the use of oral contraceptives to expedite the resolution of existing functional ovarian cysts. One cross-sectional study found that ovarian cysts resolved independently of treatment with oral contraceptives.43
Improved Acne Randomized, placebo-controlled clinical trials have demonstrated that some combination oral contraceptives will reduce acne lesions by as much as 50%.44 Several combination oral contraceptives containing new-generation progestins (e.g., norgestimate, desogestrel) or progestational anti-androgens (e.g., drospirenone in the United States, cyproterone acetate overseas) have been shown to be able to effectively reduce acne. Although it is likely that many other pill formulations will reduce acne, most formulations have not been studied for this outcome. The mechanisms by which oral contraceptives improve acne include elevation of sex hormone-binding globulin, which binds and decreases available testosterone; suppression of the enzyme that converts testosterone to dihydrotestosterone; and suppression of gonadotropins, resulting in decreased levels of ovarian androgens. Pills containing drospirenone also block the action of androgens by acting as an antagonist at the androgen receptors.
Increased Bone Density The majority of studies indicate that oral contraceptives have a positive effect on bone mineral density, and no studies have demonstrated a negative effect.45 Oral contraceptives appear to delay or prevent the decline in bone mass that begins between ages 30 and 40. Women who use oral contraceptives for 5 to 10 years or longer are afforded the greatest protection. A population-based, case-control study revealed a 25% reduction in hip fracture risk in these women.46 The positive effects of oral contraceptives on bone mineral density are due primarily to estrogen, which has been demonstrated to increase calcium absorption, decrease calcium loss, and directly decrease bone resorption by inhibiting osteoclast activity. Norethindrone also appears to have a positive effect on bone mass, although the mechanism is uncertain.
Ovarian Cysts Cyst Formation
It has been commonly accepted that moderate- and highestrogen oral contraceptives (≥50 μg ethinyl estradiol) protect against cyst formation, although the data supporting this are somewhat inconsistent. Unfortunately, current low-estrogen (≤35 μg) formulations appear to have no effect on ovarian cyst formation.39–41 However, these studies examined cysts found on ultrasound rather than symptomatic cysts. It remains to be seen whether low-estrogen (≤35 μg) oral contraceptives decrease the
Improvement in Rheumatoid Arthritis Oral contraceptives appear to diminish both the severity and symptomatology of rheumatoid arthritis but do not prevent this disease. A large meta-analysis of nine hospital and populationbased studies suggested that oral contraceptives prevent the progression of rheumatoid arthritis to more severe varieties.47 However, the protective effect was noted in the hospitalbased studies only, suggesting the possibility of some unexplained bias.
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Section 4 Contraception METABOLIC CHANGES RELATED TO COMBINATION ORAL CONTRACEPTIVES Insulin Resistance The effect of combination oral contraceptives on carbohydrate metabolism has been studied for several decades. It is now recognized that both estrogens and progestins affect glucose metabolism by increasing peripheral resistance to insulin. However, studies of women on current low-estrogen (≤35 μg) formulations have shown minimal changes in glucose and insulin levels that are of no clinical significance.48 Further, there is no evidence that combination preparations increase the risk of subsequently developing diabetes in women at risk, such as those with prior gestational diabetes.49 Women with polycystic ovary syndrome who usually demonstrate some degree of insulin resistance benefit from oral contraceptives. Although oral contraceptives may slightly increase their insulin resistance, they also reduce associated symptoms such as acne and hirsutism, regulate menses, and protect the endometrium against development of endometrial malignancy.50 Insulin-dependent diabetic women can use oral contraceptives with little fear of affecting fasting plasma glucose, insulin requirements, or glycosylated hemoglobin levels.51 However, one should avoid oral contraceptives in diabetics with evidence of vascular disease because of their increased risk of cardiovascular disease.
Changes in Lipids The estrogen component of combination oral contraceptives causes elevations in serum triglycerides but has a favorable change on the other two major lipids by elevating high-density lipoprotein cholesterol (HDL-C) while lowering low-density lipoprotein cholesterol (LDL-C) levels.52 Contraceptive formulations containing progestins with low or no androgenicity (e.g,. desogestrel, drospirenone, or norgestimate) lower LDL-C and elevate HDL-C and triglycerides. In contrast, contraceptive formulations containing more androgenic progestins may change lipids in an unfavorable direction by lowering HDL-C levels and elevating LDL-C levels.6,52–54 It is important to be aware of these differences when prescribing oral contraceptives to women with risk factors for cardiovascular disease or to those who have strong family histories of ischemic heart disease or substantial lipid abnormalities.
Cardiovascular Risk The significant areas of concern with oral contraceptives are venous thromboembolism, stroke, and myocardial infarction. However, all of these cardiovascular risks have been dramatically decreased by the significant reduction in estrogen and progestin dosages in modern formulations. Venous Thromboembolism
Multiple studies have established that women taking combination oral contraceptives containing 50 to 100 μg of ethinyl estradiol are at a small but increased risk of venous thromboembolism.57,58 It soon became clear that the risk correlates with the estrogen dose. When compared to women taking low-estrogen (≤35 μg) pills with an age-adjusted relative risk of venous thromboembolism of 1, women taking intermediate-estrogen (50 μg) pills are found to have a relative risk of 1.5, and women taking high-estrogen (>50 μg) pills have a risk of 1.7.59 However, even in the highest risk group, the absolute risk of venous thromboembolism was extremely low, at only 10 events per 10,000 women-years of use. There is some evidence that two of the newer generation progestins might also increase the risk of venous thromboembolism. Two studies published a decade ago suggested gestodene and desogestrel had a greater risk for venous thromboembolism than previously used progestins, such as levonorgestrel.60–63 Subsequent analyses and reviews have failed to reach consensus about whether these finding are real or somehow spurious.64–71 The relative incidence of venous thromboembolism in young women taking low-estrogen (≤35 μg) pills with different progestins is given in Table 26-3. At worst, the attributable risk of using oral contraceptives containing gestodene or desogestrel is only about 18 additional cases annually per 100,000 users compared to nonusers. Other risk factors for venous thromboembolism include age, obesity, pregnancy, trauma, smoking, immobilization, recent surgery, medical conditions such as cancer or collagen vascular disorders, and inherited coagulation disorders. Surprisingly, there is no evidence that cigarette smoking or varicose veins appreciably increases oral contraceptive users’ relative risk of venous thromboembolism.72 The mortality due to venous thromboembolism is low in reproductive-age women using oral contraceptives. Age Table 26-3 The Effects of Progestin Type on the Incidence of Cardiovascular Disease*
Coagulation Changes Low-estrogen (≤35 μg) oral contraception formulations are associated with clinically insignificant changes in both procoagulant and anticoagulant factors.55,56 However, women with risk factors for venous thromboembolism, such as factor V Leiden mutations, should avoid combination oral contraceptives.
MAJOR RISKS OF COMBINATION ORAL CONTRACEPTIVES
392
The major risks associated with oral contraceptive use can be grouped into disorders of the cardiovascular system and neoplasms.
Condition
Nonusers
Oral Contraceptive Users (type of progestin) Levonorgestrel/ norethindrone
Gestodene/ desogestrel
Venous thromboembolism
3.0
9.6
7.7–21.1
Stroke Ischemic Hemorrhagic
1.0 2.0
2.5 2.0
2.5 2.0
Myocardial infarction
0.2
0.5
0.2
*Rates are for women age 20–24 using low-estrogen (≤35 μg) oral contraceptives, expressed per 100,000 women annually. Adapted from Consensus conference on combination oral contraceptives and cardiovascular disease. Fertil Steril 71:1S–6S, 1999
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Chapter 26 Hormonal Contraception significantly increases this risk of mortality, such that women age 44 have twice the mortality as women age 35. Because major surgery increases the risk of venous thromboembolism, it is reasonable to discontinue oral contraceptives 3 to 4 weeks in advance. This is especially important before surgery involving extensive dissection in a lower extremity or the pelvic veins, or those that will require prolonged immobility postoperatively. For ambulatory surgery, such as tubal ligation or ovarian cystectomy, it is not recommended that oral contraceptives be discontinued before surgery because the risk of pregnancy associated with discontinuing oral contraceptives far outweighs the subsequent risk of venous thromboembolism.
stroke is increased fivefold in women using higher estrogen (≥50 μg) compared to low-estrogen (≤35 μg) oral contraceptives.78 This risk is not influenced by progestin type or duration of pill use.72,74 Age is the most important independent risk factor for stroke. The relative risk of ischemic stroke doubles as women reach age 40 to 44.74 Stroke mortality also increases by about sixfold once women reach age 35 to 44.72 Other important risk factors include hypertension, cigarette smoking, and migraine headaches. These risk factors appear to interact with oral contraceptive use to substantially increase the risk of ischemic stroke.78–81
Factor V Leiden Mutation
Hemorrhagic Stroke
The most common genetic cause of primary and recurrent venous thromboembolism in women is factor V Leiden mutation. The identification of the factor V Leiden mutation in 1993 has led to new insights into the relationship between oral contraceptive use and venous thromboembolism.73 White women have approximately 5% prevalence of a homozygous mutation; African-American and Asian women have a much lower prevalence. Women with this mutation not using oral contraceptives have a risk of venous thromboembolism of approximately 5.7 events per 10,000 women-years. In contrast, women with this mutation using oral contraceptives have an increased risk of venous thromboembolism of 28.5 events per 10,000 women-years. Screening women who desire oral contraceptives for factor Leiden V mutation would not be a cost-effective strategy in light of the low absolute risk of venous thromboembolism in women with this mutation. It has been calculated that screening 1 million potential oral contraceptive users for all known coagulation factor deficiencies or mutations would identify approximately 50 women at risk but also would result in approximately 62,000 false-positive results.69 However, screening women with a strong family history of thromboembolic events for factor V Leiden mutation remains appropriate. Certainly, a known homozygous or heterozygous factor V Leiden mutation is a relative contraindication to estrogen-containing hormonal contraceptives, although the absolute risk of thromboembolism in these patients is still relatively low.
Low-estrogen (≤35 μg) oral contraceptives do not increase the risk of hemorrhagic stroke in women with no additional risk factors, such as age greater than 35 years, cigarette smoking, or hypertension (see Table 26-3).74,77,82–86 The risk of hemorrhagic stroke is increased twofold in women using higher estrogen (≥50 μg) compared to low-estrogen (≤35 μg) oral contraceptives. This risk is not related to the type of the progestin or duration of oral contraception use. In contrast, oral contraceptive users with additional risk factors, including age greater than 35 years, cigarette smoking, or hypertension, are at slightly increased risk of hemorrhagic stroke.86 Women older than age 35 have a twofold increased risk, cigarette smokers have a threefold increased risk, and those with a history of hypertension have a 10- to 15-fold increased risk of hemorrhagic stroke while using oral contraceptives.86 Although the risk of hemorrhagic stroke for reproductive-age women is extremely low, mortality can be as high as 25%.
Stroke
Cerebrovascular accidents, commonly referred to as strokes, represent a loss of neurologic function resulting from the sudden loss of blood circulation to an area of the brain. Strokes can be classified as either ischemic (i.e., thrombotic) or hemorrhagic. Acute ischemic strokes caused by thrombosis or embolism account for 80% of all strokes. Ischemic Stroke
Low-estrogen (≤35 μg) oral contraceptives do not increase the risk of ischemic stroke in women with no additional risk factors (i.e., nonsmoking women younger than age 35 without hypertension).74 However, women with risk factors do have a somewhat increased risk. Mortality from oral contraceptive-related strokes is less than 2 per 100,000 cases. The risk of ischemic stroke in oral contraceptive users is directly proportional to estrogen dose, in a manner analogous to the risk of venous thromboembolism.72,74–77 The risk of ischemic
Myocardial Infarction
Myocardial infarction is a rare occurrence in reproductive-age women (see Table 26-3), but the fatality rate is near 30%.72 The risk of myocardial infarction is not increased in women using low-estrogen (≤35 μg) oral contraceptives who have no other risk factors such as cigarette smoking, diabetes, or hypertension. One study suggested that oral contraceptives containing gestodene or desogestrel might actually reduce risk of myocardial infarction compared to preparations containing levonorgestrel, although this finding awaits confirmation by other studies.61 Age is an important risk factor for myocardial infarction. Risk increases exponentially with age, such that women age 40 to 44 have an incidence of myocardial infarction of 30 cases per 100,000 annually.72,74 Fortunately, low-estrogen (≤35 μg) oral contraceptives do not increase the relative risk of myocardial infarction further.72 Likewise, the risk of myocardial infarction is not increased by the duration or a past history of oral contraceptive use.72,79,87–89 Cigarette smoking increases the risk of myocardial infarction regardless of whether or not women use oral contraceptives. For women who do not use oral contraceptives, cigarette smoking increases the risk of myocardial infarction by threefold to 10-fold in direct proportion to the number of cigarettes smoked daily.72 For women who use low-dose oral contraceptives, light smoking (<15 cigarettes/day) increases the risk of myocardial infarction threefold and heavy (15 cigarettes/day) increased this risk 20-fold compared to nonsmokers.90
393
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Section 4 Contraception Hypertension also increases the risk of myocardial infarction in reproductive-age women. The relative risk of myocardial infarction among oral contraceptive users with hypertension is at least threefold higher than in those with normal blood pressure.
Future Fertility
The return of menses and the achievement of a pregnancy may be slightly delayed after discontinuation of oral contraceptives, but fertility rates return to normal within 1 year.98 There is no relationship between oral contraceptive use and pituitary adenomas or subsequent amenorrhea.
Cancer Risk
Breast and cervical cancer have both been examined regarding their possible association with oral contraceptive use. Breast Cancer
Oral contraceptives appear to slightly increase the risk of breast cancer, and this increase persists for 10 years and then disappears. According to a meta-analysis of 54 studies encompassing 53,297 women with breast cancer and 100,239 controls, the relative risk of breast cancer for current users of oral contraceptives is approximately 1.24 compared to never-users.91 Breast cancers detected in oral contraceptive users tend to be localized, with a relative risk of metastases of 0.88 compared to nonusers. The increased risk of breast cancer associated with oral contraceptives is not related to hormone dose, specific formulation, duration of use, age at first use, age at time of cancer diagnosis, or family history of breast cancer. It is not universally accepted that oral contraceptives increase the risk of breast cancer, and many investigators attribute positive studies to detection bias. A recent case-control study found no increased in the risk of breast cancer for women currently taking oral contraceptives or for these same women later in life, where the risk is highest.92 This multicenter, population-based study, which involved 4575 breast cancer subjects and 4682 controls, found a relative risk of breast cancer of 1.0 (95% CI, 0.8–1.3) among current users of oral contraceptives and 0.9 (95% CI, 0.8–1.0) among former users. The relative risk did not increase with race, earlier age of starting oral contraceptives, higher estrogen doses, or positive family history of breast cancer. Cervical Cancer
Oral contraceptives appear to be associated with an increased risk of cervical cancer, especially in women with evidence of human papillomavirus infections.93 This cervical cancer risk appears to be related to duration of oral contraceptive use.94–96 With less than 5 years of oral contraceptive use, the relative risk of cervical cancer is 1.1 (95% CI, 1.1–1.2), whereas with 10 or more years of use the relative risk increases to 2.2 (95% CI, 1.9–2.4). The risk appears to be roughly the same for squamous carcinoma versus adenocarcinoma, as well as for in situ versus invasive disease. Reproductive Risks Birth Defects
394
When women using oral contraceptives accidentally conceive, they often inadvertently continue taking oral contraceptives for a short time early in the first trimester. Despite some early concerns, the vast preponderance of available evidence indicates that these women do not have an increased risk of fetal anomalies compared to the general population. Multiple prospective studies have failed to find an association between oral contraceptives and birth defects, in agreement with the results of most of the better-designed case-control studies.97
COMMON SIDE EFFECTS OF COMBINATION ORAL CONTRACEPTIVES AND THEIR MANAGEMENT Oral contraceptives are associated with bothersome side effects in some patients. Approximately one third of women will discontinue contraceptives within 6 months of starting, and in almost half of these women, the cause will be side effects.99
Nausea Approximately 50% of women report a feeling of nausea when beginning combination oral contraceptives; however, few experience vomiting. The incidence of these side effects is lower with low-estrogen (≤35 μg) pills, but still relatively frequent. Anecdotal reports suggest vitamin B6 (50 mg orally) taken daily may be of help. Other strategies include taking the pill with meals or at bedtime, decreasing the estrogen dose to 20 or 25 μg, and switching to a progestin-only contraceptive. Many gastrointestinal side effects ameliorate over time, so patients should be encouraged to try a several-month trial of oral contraceptives before discontinuing.
Breast Symptoms Estrogens can stimulate breast tissue, leading to fluid accumulation and discomfort. Combination oral contraceptive pills containing lower doses of ethinyl estradiol (20 or 25 μg) may decrease this side effect. If patients are experiencing increased breast tenderness immediately before the pill-free interval, they may actually benefit from a higher dose estrogen combination pill that more effectively inhibits ovulatory cycles. Patients should be reassured that the discomfort is not evidence of growth of a breast cancer and that with time the overall incidence of benign breast disease will decrease.
Headache Headache is a common complaint among reproductive-age women, including oral contraceptive users. A careful history can differentiate between a tension-like headache and a migraine headache. Tension headaches are often described as a dull, steady ache radiating to the neck and shoulder muscles with no neurologic deficits. Migraine headaches are typically described as recurrent episodes of throbbing pain most often accompanied by nausea and vomiting. If a migraine headache is suspected, combination oral contraceptives should be used with care. Although there are no conclusive data on differences in stroke risk for migraine with or without aura, oral contraceptive use in the former circumstance should be considered only if other contraceptive methods cannot be used and only after detailed counseling. If migraine occurs without aura in the absence of other risk factors, most women can be given a trial of oral contraceptives. Follow-up should be
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Chapter 26 Hormonal Contraception initiated within the first 2 to 3 months to assess frequency and severity of headaches. If there is an increase in frequency during the trial, a change in formulation might be considered. If headache occurs more frequently in the hormone-free interval, the physician might consider the use of extended-use oral contraceptives without a hormone-free interval. However, if the headaches become significantly more severe or frequent, oral contraceptives should be discontinued.
Irregular Bleeding Cycle control is one of the most important determinants of both contraceptive acceptability and compliance. Although reducing the daily dose of ethinyl estradiol decreases multiple health risks and symptoms without compromising efficacy, it also compromises cycle control. As many as 39% of women starting oral contraceptives with previously normal cycles will experience irregular bleeding, midcycle spotting, especially within the first 3 months.100 Women with a history of irregular menses may be even more likely to experience heavy or irregular bleeding initially. Long-term users sometimes develop amenorrhea. It is important to forewarn patients to expect changes in bleeding and to reassure them that this should resolve within three cycles and is not a sign of cancer. For women at increased risk of dysfunctional uterine bleeding (e.g., just after puberty or in the perimenopausal period) formulations containing 30 to 35 μg ethinyl estradiol may be more likely to control bleeding compared to those 20 to 25 μg. No study has demonstrated a relative advantage of either monphasic or multiphasic formulations in terms of either side effects or efficacy. Persistent abnormal uterine bleeding while using oral contraceptives requires investigation. The initial evaluation should include assessment for cervicitis, sexually transmitted infections, and cervical neoplasia. The evaluation may include sonohysterography or endometrial biopsy, as indicated. If the workup is negative, treatment may include use of a higher-estrogen (50 μg) oral contraceptive for one or two cycles or the addition of a small supplemental dose of estrogen to the patient’s current regimen.
Weight Gain There is no substantive evidence that oral contraceptives cause weight gain. However, estrogens and progestins may act as appetite stimulants or have anabolic steroid effects.
Drug Interactions with Oral Contraceptives A small number of drugs may interact with oral contraceptives (Table 26-4). There is no substantive evidence that commonly used antibiotics (e.g., tetracyclines, penicillins, or cephalosporins) or analgesics (e.g., aspirin or acetaminophen) decrease the efficacy of oral contraceptives.
Special Situations Missed Pills
Missing pills is a common problem that can decrease efficacy and increase irregular bleeding. The risk of unintended pregnancy is greatest when a pill is missed early in the cycle because follicle recruitment for ovulation may be initiated. If one pill is missed, it should be taken as soon as this is realized. If it is only
Table 26-4 Drugs and Their Potential Interactions with Oral Contraceptives Drug
Action
Effects
Rifampin
Induces cytochrome P450 enzyme
Increased steroid metabolism; decreased contraceptive efficacy
Griseofulvin
Induces hepatic enzymes
Increased steroid metabolism; decreased contraceptive efficacy
Ketoconazole Itraconazole
Inhibits cytochrome P450 enzyme
Increased estrogen levels; abnormal bleeding
Phenobarbital Phenytoin Carbamazepine Primidone Ethosuximide
Induces hepatic enzyme
Increased steroid metabolism; decreased contraceptive efficacy
Diazepam Chlordiazepoxide Tricyclic antidepressants Theophylline
Delays elimination of these drugs through a hepatic mechanism
Increased half-lives of these drugs; may require reduced doses
St. John’s wort
Hepatic enzyme activity
Increased steroid metabolism; decreased contraceptive efficacy
realized at the time of taking the pill at the regularly scheduled time, two pills should be taken. If two or more pills are missed, the risk of pregnancy is great and alternative contraception should be used for at least 1 week. Postpartum Contraception
Postpartum women who are not nursing can initiate combination oral contraceptives after the third postpartum week. Earlier initiation increases the risk of venous thromboembolism. Because ovulation is extremely unlikely to occur within 3 weeks of delivery, this delay does not impair contraceptive efficacy. Breastfeeding
The existing randomized, controlled trials are insufficient to establish an effect of hormonal contraception, if any, on milk quality and quantity.101 Based on the best available data, it appears that hormonal oral contraceptives can be used immediately postpartum. Many clinicians prefer to give progestin-only contraceptives during the first 6 months after delivery because they have no apparent deleterious effect on breastfeeding.102
ALTERNATIVE FORMULATIONS AND REGIMENS Extended-use Oral Contraceptives Extended-use oral contraceptives offer an approach whereby active combination oral contraceptive pills are taken daily for 84 days followed by a 7 day hormone-free period, rather than the usual 21 days of active pills followed by a 7-day hormone-free period used for monthly regimens. The purpose is to limit the number of withdrawal menstrual periods to four per year. This is an effective approach for the treatment of any medical condition that causes dysmenorrhea or menorrhagia or is exacerbated by menstruation, including hemorrhagic diathesis, endometriosis, uterine leiomyoma, migraine headaches, and
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Section 4 Contraception epilepsy.103–105 It can also be used for women who electively desire to reduce their days of menstrual bleeding. Originally, standard low-estrogen (≤35 μg) combination oral contraceptive pills were used for this method by having the patient discard the inert pills from four monthly packages and take one of the remaining 84 active pills daily. There is now an FDA-approved prepackaged system commercially available containing 30 μg of ethinyl estradiol and 0.15 mg levonorgestrel in each pill (see Table 26-1). Efficacy
This regimen appears to have an increased contraceptive efficacy compared to monthly regimens and may be less likely to result in unintended pregnancies when a pill is missed.105
Breastfeeding
The progestin-only pill is the oral contraceptive of choice during the first 6 months of breastfeeding, because this formulation has been shown to have no measurable adverse effect on milk volume or infant growth.102,108 Another advantage of this estrogen-free contraceptive method is that the already elevated risk of venous thromboembolism in the immediate postpartum period is not affected. Many lactating women using this type of contraception will have prolonged amenorrhea. When breastfeeding is stopped, it is reasonable to change to a combination estrogen/progestin pill if irregular bleeding becomes a problem. Risks
No major risks have been identified with progestin-only pills, although large clinical trials are lacking.
Side Effects
This approach minimizes predictable withdrawal bleeding but irregular breakthrough bleeding can occur. Accordingly, the number of bleeding days are reduced but not eliminated by this approach.106 Breakthrough bleeding occurred primarily in the initial cycles of extended-use contraception, with 59% of users still experiencing unscheduled bleeding in the fourth cycle of use. Approximately 8% of women will discontinue extended-use contraception due to irregular bleeding, compared to 2% women using a monthly pill cycle. An additional 33% will discontinue extended-use contraception due to weight gain, acne, and mood swings. Risks
Although no increased risks have yet been reported, clinical trials are necessary to determine the risk of this regimen compared to monthly cycles, particularly the risk of cancer and cardiovascular disease, and to determine the return of fertility after discontinuation of treatment.105
Progestin-only Contraceptive Pills The progestin-only oral contraceptive, or “mini-pill,” offers an estrogen-free alternative to combination oral contraceptives. The formulation contains small doses of norethindrone, levonorgestrel, or norgestrel and needs to be taken at the same time every day, starting on the first day of menses. Mechanisms of Action
Progestin-only pills do not appear to dependably inhibit ovulation.107 The contraceptive effects of this formulation are related to the ability of progestins to thin the endometrium, to thicken the cervical mucus, and possibly to interfere with tubal transport. Approximately 40% of women ovulate normally when using a progestin-only pill, even when no pills are missed. Efficacy
The reported user failure rates for progestin-only pills are from 1% to 10% per 100 women in the first year of use.10
Emergency Contraception Emergency contraception is an approach to prevent pregnancy after unprotected intercourse or known failure of a contraceptive method such as a broken or leaking condom.109 Two oral hormonal methods are currently available. Yuzpe Regimen
The Yuzpe regimen, named for the Canadian physician Dr. Albert Yuzpe, was the most commonly used postcoital contraceptive method in the United States for more than 20 years. The regimen consists of oral 0.1 mg ethinyl estradiol and 1.0 mg dl-norgestrel taken twice 12 hours apart, originally given in the form of multiple contraception pills. Currently it is recommended that the first dose be taken within 72 hours of intercourse, although limited data suggest this regimen may be effective up to 120 hours after unprotected intercourse. This method is commercially available as the Preven Emergency Contraceptive Kit. Levonorgestrel-Only
The levonorgestrel-only regimen, available commercially as Plan B, consists of administration of two doses of 0.75 mg of levonorgestrel 12 hours apart. The initial dose should be taken within 72 hours of intercourse, although recent data suggests that the first dose can be taken as long as 5 days after intercourse.110 Further, there is data to suggest that a single dose of 1.5 mg of levonorgestrel may be as effective as the two-dose regimen.110 Efficacy
Both emergency contraception formulations prevent pregnancy by delaying or inhibiting ovulation or by disrupting the function of the corpus luteum regardless of the day of the menstrual cycle.111,112 Both methods prevent almost 75% of expected pregnancies.113 One episode of unprotected intercourse near midcycle carries a pregnancy risk of about 8%. Use of the combination hormonal method or the levonorgestrel-only method reduces this rate to 2% and 1%, respectively. The earlier emergency contraception is initiated, the more effective it is.11,110
Side Effects
396
There is a high frequency of irregular uterine bleeding due to lack of estrogen to stabilize the endometrium. The exact incidence of irregular bleeding and spotting has not been well studied.
Side Effects
Using the Yuzpe regimen, approximately 50% of women will experience nausea, and 20% will have vomiting.110 Levonorgestrel emergency contraception is associated with substantially less
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Chapter 26 Hormonal Contraception nausea (23%) and vomiting (6%). These symptoms can be minimized by administrating an antiemetic (e.g., meclizine) 1 hour before taking the first pills.114
TRANSDERMAL CONTRACEPTIVE PATCH Formulation The transdermal contraceptive patch is a three-layer matrix system consisting of an outer polyester protective layer, a middle layer containing an adhesive and the contraceptive steroids, and an inner clear polyester liner that is removed before application to the skin.115 Its size is 20 cm2, roughly the size of a matchbook. The transdermal patch contains a total of 6.0 mg of norelgestromin, the active metabolite of norgestimate, and 750 μg of ethinyl estradiol. Each patch is designed to deliver 150 μg of norelgestromin and 20 μg of ethinyl estradiol daily for a 7-day period. As a safety margin, these patches will continue to secrete a contraceptive amount of hormones for 2 additional days to offer continued protection for women who forget to change their patch after 7 days. After each patch has been worn for 7 days, it is removed and a new one is applied to another skin site. Three consecutive 7-day patches are applied in a typical cycle followed by a 7-day patch-free period to allow withdrawal bleeding. Application sites that have been determined to be therapeutically equivalent in clinical trials include the buttocks, lower abdomen, upper outer arm, and upper torso except for the breasts.116
Mechanism of Action Ovulation inhibition is the primary contraceptive action of the contraceptive patch, the same mechanism of action as that of combination oral contraceptives. The transdermal contraceptive system maintains relatively steady-state serum concentrations of steroids without the characteristic peaks and troughs of an oral contraceptive.
ceptive patch users have some increase in total cholesterol, HDL-C, LDL-C, and triglycerides, but the LDL-C to HDL-C ratio is unaffected.120 The transdermal patch, much like combination oral contraceptives, increase conversion of prothrombin to thrombin, which appears to be balanced by increased fibrinolysis.121 Both the patch and oral contraceptives increase the coagulation activity marker prothombin fragment 1+2, markers for fibrinolysis, fibrin degradation products, and plasma α2-antiplasmin.
Major Risks Serious adverse events have been reported that are potentially attributable to the patch, including nonfatal pulmonary embolism, migraine headache, cholecysititis, and carcinoma in situ of the cervix.122 Although the rates of serious risks remain unknown, these rates may be similar to those for combination oral contraceptives because the transdermal patch contains the same hormones. However, a Food and Drug Administration (FDA) report has identified a potential increase in risk of venous thromboembolism.123
Side Effects The most frequently reported side effects of the transdermal patch include irregular bleeding, breast symptoms, headache, nausea, dysmenorrhea, and application site reactions.122 There is no evidence that use of the patch influences body weight. The breakthrough bleeding pattern and spotting with the transdermal contraceptive patch is similar to that seen with oral contraceptives. By about 6 months, the frequency of irregular bleeding declines substantially and remains stable. Compared to users of oral contraceptives, patch users appear to have more dysmenorrhea and more breast symptoms during the first two cycles. The breast symptoms are described as mild to moderate in 85% of women experiencing them and markedly decline with continued use of the patch. A unique side effect for patch users is application site reactions, which occur in approximately 20% of women.
Efficacy The pregnancy rate for the transdermal contraceptive patch is less than 1% per 100 women-years.115,117,118 These rates are comparable to pregnancy rates achieved with current oral contraceptives. There is also data to indicate that it is easier for women to use this method correctly compared to oral contraceptives.119 The rate of perfect compliance for the patch did not vary by age, whereas younger women pill users had lower compliance rates. Among the pregnancies reported, about one-third occurred in women weighing more than 90 kg. However, a Food and Drug Administration (FDA) report has identified a potential increase in the risk of venous thromboembolism.123
Noncontraceptive Benefits Although the noncontraceptive benefits of the transdermal patch have yet to be demonstrated, it is likely to have benefits similar to oral contraceptives because both methods use the same type of steroid hormones.
Metabolic Changes The contraceptive patch changes serum lipids and lipoproteins in a manner similar to that seen with oral contraceptives. Contra-
Management Issues Relative Contraindications
Women with contraindications to oral contraceptives should not use the patch. In addition, women with a history of significant skin allergy or exfoliative dermatologic disorders are not appropriate patch candidates. Obese women need to be counseled that their weight might reduce patch contraceptive efficacy. Patch Adherence
All transdermal delivery systems must remain adherent to be effective. Approximately 1.8% of transdermal patches will become completely detached and 2.9% partially detached prematurely.122 The contraceptive patch is designed to remain in place during activities such as saunas, whirlpool baths, and strenuous exercise. Skin adherence does not appear to be adversely affected by a vigorous, athletic lifestyle or warm, humid climates. When patches detach, users should attempt to re-attach them if possible but should not attempt to use ancillary adhesives or tape. If detachment has occurred for less than 24 hours, the cycle continues as usual with the patch being changed on the previously determined change day. If detachment has occurred for more than 24 hours, a new patch should be applied, backup
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Section 4 Contraception contraception should be used for 1 week, and the day that the new patch is applied now becomes the patch change day.
contraceptive steroid content in the ring’s reservoir for a total of 5 weeks.
Changing Patches
Efficacy
Reminder systems to ensure appropriate weekly changing of the patch, using a different site for the next application, and avoiding use of lotions or occlusive dressings may need to be used. Failure to change the transdermal contraceptive patch at the appropriate time is an important issue that needs to be addressed with patients. When a new patch cycle is delayed beyond the scheduled start day, users should be instructed that they need to apply a patch as soon as they remember and use backup contraception for at least 1 week. Further, the day they apply the patch becomes the new patch change day. If a user forgets to change the first or second patch on time, the care provider will need to know various strategies to help users get back on schedule and avoid an unplanned pregnancy. There is a 2-day period of continued release of adequate contraceptive steroid levels when the patch is left on for 2 extra days. If a user changes the patch within this window, the patch change day remains the same and there is no need for backup contraception. Failure to replace a patch after this 2-day time period increases the risk for contraceptive failure. Therefore, users will need to use backup contraception or in some instances emergency contraception if this occurs. In addition, the day she remembers to apply the patch becomes the new change day. Forgetting to remove the third patch on time carries less risk. One should instruct the user to remove it when she remembers and tell her that the change day is not altered. Finally, if one wishes to switch to a new patch change day, this should be done during the last week of a cycle when patches are not usually used.
Noncontraceptive Benefits The noncontraceptive benefits of the vaginal ring have yet to be studied. However, because the ring contains the same type of steroids as oral contraceptives, it is likely that the ring has some of the same benefits.
Metabolic Changes Although studies have not yet been done on metabolic changes associated with the vaginal ring, it is likely that the effects on lipids, coagulation, and carbohydrate metabolism will be similar to oral contraceptives.
Major Risks As with the transdermal contraceptive patch, there is little published data on the incidence or rates of major side effects. However, because the ring contains steroids similar to those utilized in oral contraceptives, the risks may be similar.
CONTRACEPTIVE VAGINAL RING
Side Effects
Formulation
Approximately 10% to 15% of users report vaginal-related symptoms, such as slight discomfort, a sensation of a foreign body, leukorrhea, vaginitis, or coital problems. Systemic side effects are similar to those seen with users of combination oral contraceptives. However, the vaginal ring appears to have a low frequency of irregular bleeding and spotting, which occurs in only 5% of cycles. This compares favorably to the incidence of irregular bleeding seen with oral contraceptives, which occurs in 5% to 39%.100,125 The irregular bleeding pattern is relatively constant for all cycles, in contrast to the declining incidence seen after several cycles of oral contraceptives.
The contraceptive vaginal ring is flexible, is composed of ethylene vinyl acetate copolymer, and is approximately 5 cm in diameter and 4 mm in thickness. Contact of the ring with the vaginal wall leads to release of ethinyl estradiol at a rate of 15 μg daily and etonogestrel (the active metabolite of desogestrel) at 120 μg daily.124 After vaginal insertion, maximum serum hormone concentrations are reached in about 1 week for progestin, and in 2 or 3 days for estrogen.123,124 After reaching maximum serum concentrations, these serum levels slowly decline. The vaginal ring results in a relatively steady serum hormone concentration similar to that seen with the contraceptive patch, in contrast to the concentration peaks and troughs seen with oral contraceptives.
Mechanism of Action
398
The reported pregnancy rate for the vaginal ring is 0.65% per 100 women-years.125 The ring maintains its efficacy even if removed for up to 3 hours, although it is designed to be left in place continuously, even during intercourse. If removed for longer than 3 hours, a backup method for contraception should be used until the ring has been in place for 7 more days. The ring has not been studied extensively in heavier women, and thus the effect of weight on efficacy is unknown.
The vaginal ring provides contraception by inhibiting ovulation with ovarian suppression similar to that achieved by oral contraceptives. This has been documented by transvaginal ultrasound measurements of follicular activity and measurements of luteinizing hormone and progesterone.124 Women are instructed to place the ring as high in their vagina as possible to avoid possible expulsion, but fitting is not required. The ring is worn for 3 weeks out of 4, although there is enough
Specific Management Issues When starting use, the vaginal ring can be inserted during the first 5 days of a menstrual period. However, backup contraception should be used for the first 7 days of ring use. If the ring is removed for more than 3 hours at any time, backup contraception should be used. Also the vaginal ring has enough hormone content for up to 5 weeks of use. Therefore, failure to remove the ring on time is not a major issue with this method. Overall acceptance of the ring is high, with 95% of users indicating satisfaction and 97% indicating they would recommend it to others.126 Major reasons cited for liking the ring include ease of remembering how to use (45%) and overall ease of use (27%). Approximately 90% of users report using the ring
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Chapter 26 Hormonal Contraception according to the instructions, a rate similar to that seen with the transdermal patch.
appears to reduce the risk of seizure activity among women with epilepsy.
INJECTABLE CONTRACEPTION
Metabolic Changes
Formulation
The metabolic changes associated with DMPA are for the most part minor. Although there are small changes in coagulation factors, these are not felt to be clinically significant.135 There are no increases in procoagulant factors, probably related to the fact that DMPA does not increase hepatic globulin production.136 Relative to lipids and lipoproteins, studies have shown either small declines in HDL-C levels and increases in LDL-C or no changes at all.135,137,138 As with most progestins, there is evidence that DMPA impairs glucose tolerance in some users, although these changes are not clinically significant.139,140
Depot medroxyprogesterone acetate (DMPA) is an aqueous suspension of 17-acetoxy-6-methyl progesterone. It is the only injectable contraception currently available in the United States.127 Although utilized as a contraceptive for at least 40 years, the FDA did not approve its use for contraception until 1992. The usual dose is 150 mg every 3 months, administered intramuscularly into either the gluteus maximus or deltoid muscles. DMPA is also available as a subcutaneous injection of 104 mg every 3 months.
Mechanism of Action The primary mechanism of action of DMPA is suppression of ovulation by suppressing the surge of gonadotropins.128 Despite suppression of gonadotropins, the ovary continues to produce estradiol at levels found in the early follicular phase of the menstrual cycle.129 Accordingly, women using DMPA do not exhibit signs or symptoms of estrogen deficiency. Other actions include thickening cervical mucus to impede ascent of sperm and thinning of the endometrium such that implantation of a blastocyst is less likely.
Efficacy The reported method failure rate for DMPA injections is 0.3% (0.3 pregnancies per 100 women-years), whereas the typical user failure rate is 3%.1 The contraceptive effectiveness of a DMPA injection persists for at least 16 weeks. This is longer than the manufacturer’s stated effectiveness of only 13 weeks after an injection, allowing for at least a 3-week margin of safety when administration of a subsequent injection is delayed.130 Unlike oral contraceptives, there is no evidence of medications that decrease the efficacy of DMPA or that DMPA alters the effectiveness of other medications. Increased weight does not affect DMPA efficacy.
Noncontraceptive Benefits A number of gynecologic health benefits are associated with use of DMPA.130–132 The risk of ectopic pregnancy is significantly lower among users compared to women not using contraception. Similar to oral contraceptives, DMPA reduces the risk of endometrial cancer by as much as 80%.133 The risk reduction is long-term and is greater for women who use DMPA for prolonged periods. Although DMPA does not protect against ovarian or breast cancer, neither does it increase risk of these malignancies. Other benefits of DMPA include reduction in the risk of pelvic inflammatory disease. By producing amenorrhea, DMPA also reduces the symptoms of endometriosis, such as dysmenorrhea. By reducing menorrhagia, DMPA also reduces the risk of iron deficiency anemia. DMPA has nongynecologic health benefits as well. Sickle cell crises are reduced in frequency by as much as 70%, although the mechanism for this effect remains unknown.134 DMPA also
Major Risks Reduced Bone Mineral Density
The most significant potential risk associated with DMPA use is a reduction in bone mineral density.130,141 DMPA decreases serum estrogen levels, which can lead to loss in bone mineral density. In women who use the drug for 5 years, bone mineral density in the spine and hip is reduced by 5% to 6% below baseline.141 Loss of bone mineral density is greatest in the first 2 years of use. In all age groups, when DMPA is discontinued bone density is usually restored to normal within 2 to 3 years. It is unknown whether use of medroxyprogesterone acetate will lead to osteoporotic fractures later in life. Until further data become available, adequate calcium intake should be encouraged for DMPA users, particularly for young women and longer term users. Cardiovascular Disease
There is no evidence that DMPA or other progestin-only contraceptives increase cardiovascular risks, such as venous thrombosis, myocardial infarction, and stroke.142 Malignancies
There is no evidence that DMPA increases the risk of endometrial, ovarian, or cervical cancer.130 Earlier case-control studies examining the risk of DMPA and breast cancer found that although overall women who used DMPA had no increased risk of breast cancer, a subset of women who had started using DMPA within the previous 5 years had a twofold increase in risk.143 However, a more recent study conducted in the United States failed to show any significant risk of breast cancer among DMPA users.144
Side Effects Menstrual Pattern Alterations
For the first 6 months of DMPA use, irregular spotting and prolonged menstrual flow is common. For women with troublesome irregular bleeding, the use of short courses of nonsteroidal anti-inflammatory agents is often helpful. With continued use, many women experience amenorrhea. The amenorrhea rate is 20% by 3 months of use and 70% after 1 year.130 Delayed Fertility
Return to fertility is delayed in patients who have used DMPA for contraception. When DMPA users stop injections in an effort
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Section 4 Contraception to achieve pregnancy, the return to baseline fertility takes an average 10 months.145 Mood Disturbances
Mood changes and depression have been reported in association with DMPA use.138 However, the studies demonstrating these findings are mostly uncontrolled. Multicenter studies have found no increase in depressive symptoms with DMPA use.146 Weight Gain
Although earlier studies suggested DMPA users may gain on average 5 pounds after 1 year of use, a recent randomized clinical trial demonstrated that DMPA is not associated with significant weight gain or changes in variables that might lead to weight gain.147
Specific Management Issues The most important determinant of contraceptive efficacy for DMPA users is their return for timely re-injection. Specially designed calendars can aid in scheduling and remembering reinjection appointments. After injection, DMPA users should avoid rubbing the injection site, because that might distribute the drug more rapidly and lead to decreased efficacy near the end of the 3-month cycle. Because menstrual patterns are altered with DMPA, proactive counseling can alleviate future concerns.
CONTRACEPTIVE IMPLANTS Implanon is the only contraceptive implant approved in the United States.148 It is a single implant 40 mm in length and 2 mm in diameter with an ethinylene vinyl acetate core that contains 68 mg of etonogestrel, the major metabolite of desogestrel. The progestin is released at rates that vary from 60 μg per day initially and slowly decreases to 30 μg daily after two years. The device is placed using a preloaded applicator in the superficial subdermal tissue on the inner aspect of the non dominant upper arm and removed after three years. The mechanism of contraceptive action includes suppression of ovulation and thickening of the cervical mucus. The pregnancy rate per 100 women-years ranges from 0.0 to 0.1. The manufacturer states that there are insufficient data on whether effectiveness decreases in women who are more than 30% above their ideal body weight. There are no clinically significant metabolic changes reported. There is no evidence of increased cardiovascular or neoplasia risk, and these risks should be similar to other progestin-only contraceptives. Since patients are not hypoestrogenic, osteoporosis
is not an issue. Menstrual irregularity is the most common side effect, with 19% experiencing amenorrhea, 27% experiencing infrequent menses, and 14% experiencing more frequent menses. However, 88% of patients with dysmenorrhea reported decreased pain. Weight gain, acne, breast pain and headache have all been reported. Following removal of the device, etonogestrel levels become undetectable within one week, and 94% of users will have return of ovulatory menstrual cycles within three to six weeks. Placement of the device does not require an incision but its removal does. The implant should be palpable; if not, an ultrasound should be ordered. Four percent of patients have implant site complications.
SUMMARY Safe and effective contraceptive methods are an important component of modern society. Currently, several hormonal methods are available, each with distinct advantages and disadvantages. There are several standard contraindications to use of hormonal contraceptive methods that utilize estrogen (see Table 26-4). For many women with these contraindications, progestin-only hormonal methods are an important alternative contraception option. Successful use of hormonal contraceptive methods requires that patients be counseled on proper use of the methods, expected risks and side effects, and any potential noncontraceptive health benefits. Finally, emergency contraception using oral hormones is a highly effective backup method when other methods have failed or been used incorrectly.
PEARLS ●
●
●
●
●
●
Hormonal contraceptives are among the most effective reversible methods ever to be used on such a large scale. Despite readily available and highly effective contraceptive methods, unplanned pregnancies continue to be a major public health problem. Side effects are a major reason for women to discontinue hormonal contraceptive methods. Oral contraceptives take a great deal of patient compliance over a long period of time and are thus difficult for some women to use successfully. Alternate contraceptive approaches associated with longer dosing intervals (e.g., transdermal patch, vaginal ring, and injectable progestin) improve both compliance and success for some women. Although a number of risks have been associated with hormonal contraceptive use, they are extremely uncommon and thus their public health significance is small.
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5. Burkman RT: Handbook of Contraception and Abortion. Boston, Little, Brown and Co., 1989. 6. Parsey KS, Pong A: An open-label, multicenter study to evaluate Yasmin, a low-dose combination oral contraceptive containing drospirenone, a new progestogen. Contraception 61:105–111, 2000. 7. Sangthawan M, Taneepanichskul S: A comparative study of monophasic oral contraceptives containing either drospirenone 3 mg or levonorgestrel 150 μg on premenstrual symptoms. Contraception 71:1–7, 2005.
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Chapter 26 Hormonal Contraception 8. Trussell J, Vaughan B: Contraceptive failure, method-related discontinuation and resumption of use: Results from the 1995 National Survey of Family Growth. Fam Plann Perspect 31:64–72, 1999. 9. Potter L, Oakley D, de Leon-Wong E, Canamar R: Measuring compliance among oral contraceptive users. Fam Plann Perspect 28:154–158, 1996. 10. Trussell J, Kost K: Contraceptive failure in the United States: A critical review of the literature. Stud Fam Plann 18:237–283, 1987. 11. Trussell J, Rodriguez G, Ellertson C: Updated estimates of the effectiveness of the Yuzpe regimen of emergency contraception. Contraception 59:147–151, 1999. 12. Trussel LJ, Hatcher RA, Cates W, et al: A guide to interpreting contraceptive efficacy studies. Obstet Gynecol 76:558–567, 1990. 13. Peterson HB, Lee NC: The health effects of oral contraceptives: Misperceptions, controversies, and continuing good news. Clin Obstet Gynecol 32:339–355, 1989. 14. Mishell DR Jr. Noncontraceptive health benefits of oral steroidal contraceptives. Am J Obstet Gynecol 142:809–816, 1982. 15. Burkman RT Jr: Noncontraceptive effects of hormonal contraceptives: Bone mass, sexually transmitted disease and pelvic inflammatory disease, cardiovascular disease, menstrual function, and future fertility. Am J Obstet Gynecol 170:1569–1575, 1994. 16. Ness RB, Soper DE, Holley RL, et al: Hormonal and barrier contraception and risk of upper genital tract disease in the PID Evaluation and Clinical Health (PEACH) study. Am J Obstet Gynecol 185:121–127, 2001. 17. Schlesselman JJ: Risk of endometrial cancer in relation to use of combined oral contraceptives. A practitioner’s guide to meta-analysis. Hum Reprod 12:1851–1863, 1997. 18. Sherman ME, Sturgeon S, Brinton LA, et al: Risk factors and hormone levels in patients with serous and endometrioid uterine carcinomas. Mod Pathol 10:963–968, 1997. 19. Vessey MP, Painter R: Endometrial and ovarian cancer and oral contraceptives—findings in a large cohort study. Br J Cancer 71:1340–1342, 1995. 20. Hankinson SE, Colditz GA, Hunter DJ, et al: A quantitative assessment of oral contraceptive use and risk of ovarian cancer. Obstet Gynecol 80:708–714, 1992. 21. Piver MS, Baker TR, Jishi MF, et al: Familial ovarian cancer. A report of 658 families from the Gilda Radner Familial Ovarian Cancer Registry 1981–1991. Cancer 71:582–588, 1993. 22. Risch HA, Marrett LD, Jain M, Howe GR: Differences in risk factors for epithelial ovarian cancer by histologic type. Results of a casecontrol study. Am J Epidemiol 144:363–372, 1996. 23. Rodriguez GC, Walmer DK, Cline M, et al: Effect of progestin on the ovarian epithelium of macaques: Cancer prevention through apoptosis? J Soc Gynecol Investig 5:271–276, 1998. 24. Martinez ME, Grodstein F, Giovannucci E, et al: A prospective study of reproductive factors, oral contraceptive use, and risk of colorectal cancer. Cancer Epidemiol Biomarkers Prev 6:1–5, 1997. 25. Potter JD, McMichael AJ: Large bowel cancer in women in relation to reproductive and hormonal factors: A case-control study. J Natl Cancer Inst 71:703–709, 1983. 26. Fernandez E, La Vecchia C, Franceschi S, et al: Oral contraceptive use and risk of colorectal cancer. Epidemiology 9:295–300, 1998. 27. Troisi R, Schairer C, Chow WH, et al: A prospective study of menopausal hormones and risk of colorectal cancer (United States). Cancer Causes Control 8:130–138, 1997. 28. Crandall CJ: Estrogen replacement therapy and colon cancer: A clinical review. J Womens Health Gend Based Med 8:1155–1166, 1999. 29. Klein JR, Litt IF: Epidemiology of adolescent dysmenorrhea. Pediatrics 68:661–664, 1981. 30. Wilson CA, Keye WR Jr: A survey of adolescent dysmenorrhea and premenstrual symptom frequency. A model program for prevention, detection, and treatment. J Adolesc Health Care 10:317–322, 1989. 31. van Hooff MH, Hirasing RA, Kaptein MB, et al: The use of oral contraceptives by adolescents for contraception, menstrual cycle problems or acne. Acta Obstet Gynecol Scand 77:898–904, 1998.
32. Weng LJ, Xu D, Zheng HZ, et al:. Clinical experience with triphasic oral contraceptive (Triquilar) in 527 women in China. Contraception 43:263–71, 1991. 33. Milman N, Clausen J, Byg KE: Iron status in 268 Danish women aged 18–30 years: Influence of menstruation, contraceptive method, and iron supplementation. Ann Hematol 77:13–19, 1998. 34. Davis A, Lippman J, Godwin A, et al: Triphasic norgestimate/ethinyl estradiol oral contraceptive for the treatment of dysfunctional uterine bleeding. Obstet Gynecol 95:S84, 2000. 35. Dawood MY: Dysmenorrhea. Clin Obstet Gynecol 33:168–178, 1990. 36. Chan WY, Dawood MY: Prostaglandin levels in menstrual fluid of nondysmenorrheic and of dysmenorrheic subjects with and without oral contraceptive or ibuprofen therapy. Adv Prostaglandin Thromboxane Res 8:1443–1447, 1980. 37. Brinton LA, Vessey MP, Flavel R, Yeates D: Risk factors for benign breast disease. Am J Epidemiol 113:203–214, 1981. 38. Charreau I, Plu-Bureau G, Bachelot A, et al: Oral contraceptive use and risk of benign breast disease in a French case-control study of young women. Eur J Cancer Prev 2:147–154, 1993. 39. Lanes SF, Birmann B, Walker AM, Singer S: Oral contraceptive type and functional ovarian cysts. Am J Obstet Gynecol 166:956–961, 1992. 40. Young RL, Snabes MC, Frank ML, Reilly M: A randomized, doubleblind, placebo-controlled comparison of the impact of low-dose and triphasic oral contraceptives on follicular development. Am J Obstet Gynecol 167:678–682, 1992. 41. Holt VL, Cushing-Haugen KL, Daling JR: Oral contraceptives, tubal sterilization, and functional ovarian cyst risk. Obstet Gynecol 102:252–258, 2003. 42. Tayob Y, Adams J, Jacobs HS, Guillebaud J: Ultrasound demonstration of increased frequency of functional ovarian cysts in women using progestogen-only oral contraception. BJOG 92:1003–1009, 1985. 43. Christensen JT, Boldsen JL, Westergaard JG: Functional ovarian cysts in premenopausal and gynecologically healthy women. Contraception 66:153–157, 2002. 44. Redmond GP, Olson WH, Lippman JS, et al: Norgestimate and ethinyl estradiol in the treatment of acne vulgaris: A randomized, placebocontrolled trial. Obstet Gynecol 89:615–622, 1997. 45. DeCherney A: Bone-sparing properties of oral contraceptives. Am J Obstet Gynecol 174:15–20, 1996. 46. Michaelsson K, Baron JA, Farahmand BY, et al: Oral contraceptive use and risk of hip fracture: A case-control study. Lancet 353:1481–1484, 1999. 47. Spector TD, Hochberg MC: The protective effect of the oral contraceptive pill on rheumatoid arthritis: An overview of the analytic epidemiological studies using meta-analysis. J Clin Epidemiol 43:1221–1230, 1990. 48. Gaspard UJ, Lefebvre PJ: Clinical aspects of the relationship between oral contraceptives, abnormalities in carbohydrate metabolism, and the development of cardiovascular disease. Am J Obstet Gynecol 163:334–343, 1990. 49. Kjos SL, Shoupe D, Douyan S, et al: Effect of low-dose oral contraceptives on carbohydrate and lipid metabolism in women with recent gestational diabetes: Results of a controlled, randomized, prospective study. Am J Obstet Gynecol 163:1822–1827, 1990. 50. Guzick DS: Polycystic ovary syndrome. Obstet Gynecol 103:181–193, 2004. 51. Kjos SL, Peters RK, Xiang A, et al: Contraception and the risk of type 2 diabetes mellitus in Latina women with prior gestational diabetes mellitus. JAMA 280:533–538, 1998. 52. LaRosa JC: Effects of oral contraceptives on circulating lipids and lipoproteins: Maximizing benefit, minimizing risk. Int J Fertil 34(Suppl):71–84, 1989. 53. Chapdelaine A, Desmarais JL, Derman RJ: Clinical evidence of the minimal androgenic activity of norgestimate. Int J Fertil 34:347–352, 1989. 54. Lobo RA, Skinner JB, Lippman JS, Cirillo SJ: Plasma lipids and desogestrel and ethinyl estradiol: A meta-analysis. Fertil Steril 65:1100–1109, 1996.
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55. Speroff L, DeCherney A: Evaluation of a new generation of oral contraceptives. The Advisory Board for the New Progestins. Obstet Gynecol 81:1034–1047, 1993. 56. Conard J: Biological coagulation findings in third-generation oral contraceptives. Hum Reprod Update 5:672–680, 1999. 57. Stadel BV: Oral contraceptives and cardiovascular disease (first of two parts). NEJM 305:612–618, 1981. 58. Stadel BV: Oral contraceptives and cardiovascular disease (second of two parts). NEJM 305:672–677, 1981. 59. Gerstman BB, Piper JM, Tomita DK, et al: Oral contraceptive estrogen dose and the risk of deep venous thromboembolic disease. Am J Epidemiol 133:32–37, 1991. 60. Bloemenkamp KW, Rosendaal FR, Helmerhorst FM, et al: Enhancement by factor V Leiden mutation of risk of deep-vein thrombosis associated with oral contraceptives containing a third-generation progestagen. Lancet 346:1593–1596, 1995. 61. Lewis MA, Heinemann LA, Spitzer WO, et al: The use of oral contraceptives and the occurrence of acute myocardial infarction in young women. Results from the Transnational Study on Oral Contraceptives and the Health of Young Women. Contraception 56:129–140, 1997. 62. Farmer RD, Lawrenson RA, Thompson CR, et al: Population-based study of risk of venous thromboembolism associated with various oral contraceptives. Lancet 349:83–88, 1997. 63. Spitzer WO: Bias versus causality: Interpreting recent evidence of oral contraceptive studies. Am J Obstet Gynecol 179:S43–S50, 1998. 64. Lawrenson R, Farmer R: Venous thromboembolism and combined oral contraceptives: Does the type of progestogen make a difference? Contraception 62:21S–28S, 2000. 65. Spitzer WO: Oral contraceptives and cardiovascular outcomes: Cause or bias? Contraception 62:3S–9S, 2000. 66. Farmer RD, Williams TJ, Simpson EL, Nightingale AL: Effect of 1995 pill scare on rates of venous thromboembolism among women taking combined oral contraceptives: Analysis of general practice research database. BMJ 321:477–479, 2000. 67. Jick H, Kaye JA, Vasilakis-Scaramozza C, Jick SS: Risk of venous thromboembolism among users of third generation oral contraceptives compared with users of oral contraceptives with levonorgestrel before and after 1995: Cohort and case-control analysis. BMJ 321:1190–1195, 2000. 68. Skegg DC: Pitfalls of pharmacoepidemiology. BMJ 321:1171–1172, 2000. 69. Winkler UH: Hemostatic effects of third- and second-generation oral contraceptives: Absence of a causal mechanism for a difference in risk of venous thromboembolism. Contraception 62:11S–20S, 2000 70. Vandenbroucke JP, Rosing J, Bloemenkamp KW, et al: Oral contraceptives and the risk of venous thrombosis. NEJM 344:1527–1535, 2001. 71. Kemmeren JM, Algra A, Grobbee DE: Third generation oral contraceptives and risk of venous thrombosis: Meta-analysis. BMJ 323:131–134, 2001. 72. WHO Scientific Group: Cardiovascular Disease and Steroid Hormone Contraception. Geneva, World Health Organization, 1998. 73. Dahlback B, Carlsson M, Svensson PJ: Familial thrombophilia due to a previously unrecognized mechanism characterized by poor anticoagulant response to activated protein C: Prediction of a cofactor to activated protein C. Proc Natl Acad Sci USA 90:1004–1008, 1993. 74. Consensus conference on combination oral contraceptives and cardiovascular disease. Fertil Steril 71:1S–6S, 1999. 75. Heinemann LA, Lewis MA, Thorogood M, et al: Case-control study of oral contraceptives and risk of thromboembolic stroke: Results from International Study on Oral Contraceptives and Health of Young Women. BMJ 315:1502–1504, 1997. 76. Lidegaard O: Oral contraception and risk of a cerebral thromboembolic attack: Results of a case-control study. B 306:956–963, 1993. 77. Vessey MP, Lawless M, Yeates D: Oral contraceptives and stroke: Findings in a large prospective study. (Clin Res Ed) 289:530–531, 1984. 78. Ischaemic stroke and combined oral contraceptives: Results of an international, multicentre, case-control study. WHO Collaborative Study of Cardiovascular Disease and Steroid Hormone Contraception. Lancet 348:498–505, 1996.
79. Sidney S, Siscovick DS, Petitti DB, et al: Myocardial infarction and use of low-dose oral contraceptives: A pooled analysis of 2 U.S. studies. Circulation 98:1058–1063, 1998. 80. Tzourio C, Tehindrazanarivelo A, Iglesias S, et al: Case-control study of migraine and risk of ischaemic stroke in young women. BMJ 310:830–833, 1995. 81. Chang CL, Donaghy M, Poulter N: Migraine and stroke in young women: Case-control study. The World Health Organisation Collaborative Study of Cardiovascular Disease and Steroid Hormone Contraception. BMJ 318:13–18, 1999. 82. Petitti DB, Sidney S, Bernstein A, et al: Stroke in users of low-dose oral contraceptives. NEJM 335:8–15, 1996. 83. Hannaford PC, Croft PR, Kay CR: Oral contraception and stroke. Evidence from the Royal College of General Practitioners’ Oral Contraception Study. Stroke 25:935–942, 1994. 84. Schwartz SM, Siscovick DS, Longstreth WT Jr, et al: Use of low-dose oral contraceptives and stroke in young women. Ann Intern Med 127:596–603, 1997. 85. Thorogood M, Mann J, Murphy M, Vessey M: Fatal stroke and use of oral contraceptives: Findings from a case-control study. Am J Epidemiol 136:35–45, 1992. 86. Haemorrhagic stroke, overall stroke risk, and combined oral contraceptives: Results of an international, multicentre, case-control study. WHO Collaborative Study of Cardiovascular Disease and Steroid Hormone Contraception. Lancet 348:505–510, 1996. 87. Rosenberg L, Palmer JR, Lesko SM, Shapiro S: Oral contraceptive use and the risk of myocardial infarction. Am J Epidemiol 131:1009–1016, 1990. 88. Stampfer MJ, Willett WC, Colditz GA, et al: A prospective study of past use of oral contraceptive agents and risk of cardiovascular diseases. NEJM 319:1313–1317, 1988. 89. Croft P, Hannaford PC: Risk factors for acute myocardial infarction in women: Evidence from the Royal College of General Practitioners’ oral contraception study. BMJ 298:165–168, 1989. 90. Basdevant A, Conard J, Pelissier C, et al: Hemostatic and metabolic effects of lowering the ethinyl estradiol dose from 30 μg to 20 μg in oral contraceptives containing desogestrel. Contraception 48:193–203, 1993. 91. Collaborative Group on Hormonal Factors in Breast Cancer (CGoHFiB): Breast cancer and hormonal contraceptives: Collaborative reanalysis of individual data on 53,297 women with breast cancer and 100,239 women without breast cancer from 54 epidemiological studies. Lancet 347:1713–1727, 1996. 92. Marchbanks PA, McDonald JA, Wilson HG, et al: Oral contraceptives and the risk of breast cancer. NEJM 346:2025–2032, 2002; 93. World Health Organization: Cervical cancer, oral contraceptives, and parity. Geneva, WHO, 2002. 94. Smith JS, Green J, Berrington de Gonzalez A, et al: Cervical cancer and use of hormonal contraceptives: A systematic review. Lancet 361:1159–1167, 2003. 95. Green J, Berrington de Gonzalez A, Sweetland S, et al: Risk factors for adenocarcinoma and squamous cell carcinoma of the cervix in women aged 20–44 years: The UK National Case-Control Study of Cervical Cancer. Br J Cancer 89:2078–2086, 2003. 96. Moreno V, Bosch FX, Munoz N, et al: Effect of oral contraceptives on risk of cervical cancer in women with human papillomavirus infection: The IARC multicentric case-control study. Lancet 359:1085–1092, 2002. 97. Bracken MB: Oral contraception and congenital malformations in offspring: A review and meta-analysis of the prospective studies. Obstet Gynecol 76:552–557, 1990. 98. Huggins GR, Cullins VE: Fertility after contraception or abortion. Fertil Steril 54:559–573, 1990. 99. Rosenberg MJ, Waugh MS: Oral contraceptive discontinuation: A prospective evaluation of frequency and reasons. Am J Obstet Gynecol 179:577–582, 1998. 100. Bjarnadottir RI, Tuppurainen M, Killick SR: Comparison of cycle control with a combined contraceptive vaginal ring and oral levonorgestrel/ethinyl estradiol. Am J Obstet Gynecol 186:389–395, 2002.
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Chapter 26 Hormonal Contraception 101. Truitt ST, Fraser AB, Grimes DA, et al: Combined hormonal versus nonhormonal versus progestin-only contraception in lactation. Cochrane Database Sys Rev 2003:CD003988. 102. Kelsey JJ: Hormonal contraception and lactation. J Hum Lact 12:315–318, 1996. 103. Sulak PJ, Cressman BE, Waldrop E, et al: Extending the duration of active oral contraceptive pills to manage hormone withdrawal symptoms. Obstet Gynecol 89:179–183, 1997. 104. Sulak PJ, Kuehl TJ, Ortiz M, Shull BL: Acceptance of altering the standard 21-day/7-day oral contraceptive regimen to delay menses and reduce hormone withdrawal symptoms. Am J Obstet Gynecol 186:1142–1149, 2002. 105. Wiegratz I, Kuhl H: Long-cycle treatment with oral contraceptives. Drugs 64:2447–2462, 2004. 106. Anderson FD, Hait H: A multicenter, randomized study of an extended cycle oral contraceptive. Contraception 68:89–96, 2003. 107. Moghissi KS, Syner FN, McBride LC: Contraceptive mechanism of microdose norethindrone. Obstet Gynecol 41:585–594, 1973. 108. Tankeyoon M, Dusitsin N, Chalapati S, et al: Effects of hormonal contraceptives on milk volume and infant growth. WHO Special Programme of Research, Development and Research Training in Human Reproduction Task force on oral contraceptives. Contraception 30:505–522, 1984. 109. Westhoff C: Clinical practice. Emergency contraception. NEJM 349:1830–1835, 2003. 110. Dunn S, Guilbert E, Lefebvre G, et al: Emergency contraception. J Obstet Gynaecol Can 25:673–687, 2003. 111. Piaggio G, von Hertzen H, Grimes DA, Van Look PF: Timing of emergency contraception with levonorgestrel or the Yuzpe regimen. Task Force on Postovulatory Methods of Fertility Regulation. Lancet 353:721, 1999. 112. Trussell J, Rodriguez G, Ellertson C: New estimates of the effectiveness of the Yuzpe regimen of emergency contraception. Contraception 57:363–369, 1998. 113. Grimes DA, Raymond EG: Emergency contraception. Ann Intern Med 137:180–189, 2002. 114. Raymond EG, Creinin MD, Barnhart KT, et al: Meclizine for prevention of nausea associated with use of emergency contraceptive pills: A randomized trial. Obstet Gynecol 95:271–277, 2000. 115. Audet MC, Moreau M, Koltun WD, et al: Evaluation of contraceptive efficacy and cycle control of a transdermal contraceptive patch vs an oral contraceptive: A randomized controlled trial. JAMA 285:2347–2354, 2001. 116. Abrams LS, Skee DM, Natarajan J, et al: Pharmacokinetics of a contraceptive patch (Evra/Ortho Evra) containing norelgestromin and ethinyloestradiol at four application sites. Br J Clin Pharmacol 53:141–146, 2002. 117. Smallwood GH, Meador ML, Lenihan JP, et al: Efficacy and safety of a transdermal contraceptive system. Obstet Gynecol 98:799–805, 2001. 118. Hedon B, Helmerhorst FM, Cronje HS, Shangold G, Fisher AC, Creasy G. Comparison of efficacy, cycle control, compliance, and safety in users of a contraceptive patch vs. an oral contraceptive. Int J Obstet Gynecol 70:78, 2000. 119. Archer DF, Bigrigg A, Smallwood GH, et al: Assessment of compliance with a weekly contraceptive patch (Ortho Evra/Evra) among North American women. Fertil Steril 77(Suppl 2):27–31, 2002. 120. Creasy G, Fisher AC, Hall N, Shangold G: Effect of a contraceptive patch vs. placebo (PBO) on serum lipid profile. Fertil Steril 74(Suppl): S185, 2000. 121. Kluft C: Renewed interest in haemostasis changes induced by oral contraceptives (OCs). Thromb Haemost 84:1–3, 2000. 122. Sibai BM, Odlind V, Meador ML, et al:. A comparative and pooled analysis of the safety and tolerability of the contraceptive patch (Ortho Evra/Evra). Fertil Steril 77(Suppl):S19–S26, 2002. 123. United States Food and Drug Administration. Press release, September 21, 2006. 124. Timmer CJ, Mulders TM: Pharmacokinetics of etonogestrel and ethinylestradiol released from a combined contraceptive vaginal ring. Clin Pharmacokin 39:233-242, 2000.
125. Roumen FJ, Apter D, Mulders TM, Dieben TO: Efficacy, tolerability and acceptability of a novel contraceptive vaginal ring releasing etonogestrel and ethinyl oestradiol. Hum Reprod 16:469–475, 2001. 126. Novak A, de la Loge C, Abetz L, van der Meulen EA: The combined contraceptive vaginal ring, NuvaRing: An international study of user acceptability. Contraception 67:187–194, 2003. 127. Kaunitz AM: Current concepts regarding use of DMPA. J Reprod Med 47:785–789, 2002. 128. Mishell DR Jr, Kletzky OA, Brenner PF, et al: The effect of contraceptive steroids on hypothalamic-pituitary function. Am J Obstet Gynecol 128:60–74, 1977. 129. Jeppsson S, Gershagen S, Johansson ED, Rannevik G: Plasma levels of medroxyprogesterone acetate (MPA), sex-hormone binding globulin, gonadal steroids, gonadotrophins and prolactin in women during longterm use of depot-MPA (Depo-Provera) as a contraceptive agent. Acta Endocrinol (Copenh) 99:339–343, 1982. 130. Kaunitz AM: Injectable contraception. New and existing options. Obstet Gynecol Clin North Am 27:741–780, 2000. 131. Cullins VE: Noncontraceptive benefits and therapeutic uses of depot medroxyprogesterone acetate. J Reprod Med 41:428–433, 1996. 132. Westhoff C: Depot-medroxyprogesterone acetate injection (DepoProvera): A highly effective contraceptive option with proven longterm safety. Contraception 68:75–87, 2003. 133. Thomas D, Ray RM: Depot-medroxyprogesterone acetate (DMPA) and risk of endometrial cancer. The WHO Collaborative Study of Neoplasia and Steroid Contraceptives. Int J Cancer 49:186–190, 1991. 134. De Ceulaer K, Gruber C, Hayes R, Serjeant GR: Medroxyprogesterone acetate and homozygous sickle-cell disease. Lancet 2:229–231, 1982. 135. Fahmy K, Khairy M, Allam G, et al: Effect of depot-medroxyprogesterone acetate on coagulation factors and serum lipids in Egyptian women. Contraception 44:431–444, 1991. 136. Fraser IS, Weisberg E: A comprehensive review of injectable contraception with special emphasis on depot medroxyprogesterone acetate. Med J Aust 1:3–19, 1981. 137. Kremer J, de Bruijn HW, Hindriks FR: Serum high density lipoprotein cholesterol levels in women using a contraceptive injection of depotmedroxyprogesterone acetate. Contraception 22:359–367, 1980. 138. Westhoff C: Depot medroxyprogesterone acetate contraception. Metabolic parameters and mood changes. J Reprod Med 41:401–406, 1996. 139. Liew DF, Ng CS, Yong YM, Ratnam SS: Long-term effects of DepoProvera on carbohydrate and lipid metabolism. Contraception 31:51–64, 1985. 140. Kamau RK, Maina FW, Kigondu C, Mati JK: The effect of low-oestrogen combined pill, progestogen-only pill and medroxyprogesterone acetate on oral glucose tolerance test. East Afr Med J 67:550–555, 1990. 141. Wooltorton E: Medroxyprogesterone acetate (Depo-Provera) and bone mineral density loss. Can Med Assoc J 172:746, 2005. 142. Cardiovascular disease and use of oral and injectable progestogen-only contraceptives and combined injectable contraceptives. Results of an international, multicenter, case-control study. World Health Organization Collaborative Study of Cardiovascular Disease and Steroid Hormone Contraception. Contraception 57:315–324, 1998. 143. Skegg DC, Noonan EA, Paul C, et al: Depot medroxyprogesterone acetate and breast cancer. A pooled analysis of the World Health Organization and New Zealand studies. JAMA 273:799–804, 1995. 144. Strom BL, Berlin JA, Weber AL, et al: Absence of an effect of injectable and implantable progestin-only contraceptives on subsequent risk of breast cancer. Contraception 69:353–360, 2004. 145. Schwallie PC, Assenzo JR: The effect of depot-medroxyprogesterone acetate on pituitary and ovarian function, and the return of fertility following its discontinuation: A review. Contraception 10:181–202, 1974. 146. Kaunitz AM: Long-acting hormonal contraception: Assessing impact on bone density, weight, and mood. Int J Fertil Womens Med 44:110–117, 1999. 147. Pelkman C: Hormones and weight change. J Reprod Med 47:791–794, 2002. 148. Meckstroth KR, Darney PD: Implant contraception. Semin Reprod Med 19:339–354, 2001.
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Modern Concepts in Intrauterine Devices Janice Duke and Sheela Barhan
INTRODUCTION The intrauterine device (IUD) represents a unique approach to birth control and was the first woman-initiated contraceptive device to become widely available. From the beginning, it had the advantages of reversibility and relative effectiveness. In the past, these benefits were offset by the disadvantage of requiring placement by a healthcare provider, as well as by a spectrum of side effects and serious risks. Over the years, technological improvements have resulted in the evolution of the IUD into a highly efficacious and safe contraceptive method. Worldwide, it has become the most widely used form of reversible contraception. In Western Europe, 7% to 18% of women using contraception have an IUD.1 In the United States, less than 1% of women use an IUD for contraception, primarily because of reports of infectious complications resulting from IUDs no longer in use.2 This chapter offers a brief history of the IUD, common characteristics of modern IUDs, contraceptive effectiveness, noncontraceptive benefits, risks, and complications associated with IUD use. In addition, the chapter describes methods for IUD replacement and removal.
HISTORY It has long been alleged that the idea for a human IUD arose from Arab traders’ use of stones in the uterine cavities of camels to prevent unplanned pregnancies. Regretfully, this fascinating story appears to have no basis in fact.3 In actuality, the IUD appears to have evolved in the early 1800s from the stem pessary. This cup-shaped device had a stem that fit into the cervical canal and was designed to be placed in the vagina to support the uterus or rectum. It was soon found to have some contraceptive effectiveness, and in 1902 Hallwig designed a version with a stem that extended into the uterine cavity. This device, sold without prescription for self-insertion, was associated with a high infection rate and was not endorsed by the medical community. In 1909, Richter designed the first true IUD, which was a ring made of silkworm gut. In 1923, Pust combined this ring with a button and a catgut thread for retrieval. These devices were widely utilized during World War I, but like the stem pessary, they had an unacceptably high infection rate. In 1930 in Germany, Gräfenberg introduced a silver ring IUD without the tail common to earlier versions (Fig. 27-1). This contraceptive device had the drawback of a high expulsion rate. In 1934 in Japan, Ota modified this design slightly by adding a supportive structure to the ring. Both of these pioneers were
ostracized by their respective medical communities. Regardless of their personal lack of success, their innovative work proved to be the first effective female-initiated contraceptive technique with a reasonably low risk of side effects and complications. Based on these attributes and a lack of equivalent alternative methods, IUD use gradually spread throughout the world. Intrauterine devices gained wide popularity in the 1960s and 1970s with the introduction of such models as the Margulies Spiral, the Lippes Loop, the Saf-T-Coil, the Birnberg bow, and the Dalkon Shield (see Fig. 27-1).4 In 1962, the Population Council convened the first International IUD Conference in New York City to analyze IUD data. In 1970, the Population Council published a report that concluded that IUDs were generally safe and an efficacious method of birth control.5 With this endorsement, IUD utilization increased rapidly. By early 1970, there were more than 70 IUDs on the market, which together made up 10% of the contraceptives used in the United States.
Inert IUDs The IUDs approved by the Food and Drug Administration (FDA) in the 1960s and 1970s (e.g., Lippes Loop, Saf-T-Coil) were made of plastic (see Fig. 27-1). The pregnancy rates associated with the use of these IUDs were almost 20% per year. Another problem with this generation of IUD was that their relatively large size and shapes resulted in an unacceptable rate of increased menstrual bleeding and discomfort. The Dalkon Shield
The Dalkon Shield was a uniquely designed IUD, whose associated complications resulted in the diminished popularity of IUDs in the United States that continues to this day. The Dalkon Shield, introduced by the A. H. Robbins Company in 1971, was a plastic ring to which had been added lateral spikes to decrease the expulsion rate, a central membrane, and a braided multifilament tailstring for removal (see Fig. 27-1). By 1974, more than 2.8 million women in the United States were using the Dalkon Shield. By coincidence, the early 1970s witnessed a period of increased sexual freedom referred to as the Sexual Revolution, which was associated with a corresponding increase in the prevalence of sexually transmitted diseases and pelvic inflammatory disease (PID). The first indications of a problem were case reports of adverse IUD-related events, including PID, ectopic pregnancy, and septic abortions, some of which were fatal.6 Systematic investigations ultimately concluded that the Dalkon Shield, in particular, was associated with an increased risk of infectious
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Gräfenberg ring
Lippes loop
Figure 27-1
Saf-T-Coil
Dalkon Shield
Historical IUDs no longer available.
complications. When tailstrings from different IUD models were cultured, the braided Dalkon Shield tailstrings were found to grow several types of bacteria, whereas monofilament tailstring from other IUDs had no positive cultures.7 This information supported the hypothesis that the increased risk of pelvic infection associated with the Dalkon Shield was the result of a wicking action of the braided tailstring that facilitated the ascent of bacteria into the upper genital tract. After only 3 years in production, the Dalkon Shield was taken off the U.S. market in 1974. Public and physician fear of infectious complications led to a sharp decline in use of all IUDs. From 1985 to 1988, only the Progestasert IUD was available in the United States. Despite multiple studies documenting the safety of modern IUDs and numerous design improvements, which have increased contraceptive efficacy and decreased unwanted side effects, the negative image of IUDs remains.
Copper-containing IUDs Since the introduction of modern IUDs, research has focused on ways to increase their contraceptive efficacy, first by altering their configuration and then by including some pregnancypreventing substance in their design. Studies in rabbits indicate that intrauterine placement of either copper or zinc could prevent implantation.8 Based on this information, copper-containing IUDs were developed for humans. These first “medicated” IUDs had copper wire wrapped around the vertical stem of a T-shaped IUD. Earlier copper IUDs contained from 30 to 200 mm2 of copper.9 Animal studies indicated that adding higher amounts of copper dramatically enhanced contraceptive efficacy. The copper-containing ParaGard IUD, introduced in 1988, contains 300 mm2 of copper on the vertical arm and 40 mm2 on each of the horizontal arms, for a total of 380 mm2 (Fig. 27-2). This amount of copper decreased the pregnancy rate to less than 1% with copper. For the first time, the failure rate of an IUD was comparable to oral and injectable contraceptive methods and rivaled that of surgical sterilization. The ParaGard IUD is one of two IUDs currently available in the United States today.
The First Progestin-impregnated IUD
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Hormone-impregnated IUDs were also evaluated to determine if they increase contraceptive efficacy. In 1976, the first progestinreleasing IUD was introduced to the market as the Progestasert. This T-shaped IUD had a vertical stem containing 38 mg of progesterone, which was released at a rate of 65 μg/day. In addition to contraception, it offered the additional benefit of diminished menstrual bleeding and discomfort. However, due to a failure rate of 2.9% and need for annual replacement, it was
ParaGard Figure 27-2
Mirena
Modern IUDs currently available in the United States.
never widely utilized and its production was discontinued in 2001. The efficacy of this approach was greatly improved by the use of the more potent progestin levonorgestrel. The levonorgestrel-containing Mirena IUD is the second of two IUDs available in the United States today (see Fig. 27-2).
MODERN INTRAUTERINE DEVICES Two IUDs are currently available in the United States; the copper T 380A (ParaGard, Ortho Pharmaceutical Corp., Raritan, N.J.) and the levonorgestrel intrauterine system (Mirena, Berlex Pharmaceuticals, Montville, N.J.) (see Fig. 27-2). Both are highly effective for preventing pregnancy with acceptable side effect profiles. The Mirena has the added benefit of decreasing both menstrual flow and discomfort in many patients.
The Copper-containing ParaGard IUD The ParaGard IUD, introduced in 1988, has a flexible plastic T frame (see Fig. 27-2). A copper wire is wound around the stem, and copper sleeves are attached to the horizontal bars for a total copper surface area of 380 mm2. A monofilament tailstring is attached to the end of the vertical stem. The pregnancy failure rate for the ParaGard IUD is less than 1%, and it was originally approved by the FDA for 4 years of use before removal and replacement. However, subsequent studies showed that the ParaGard IUD could be used much longer without a decline in efficacy, and it is currently approved for 10 years of use. It has withstood the test of time with proven safety and patient tolerance.
The Levonorgestrel-containing Mirena IUD The levonorgestrel-containing Mirena IUD is a direct descendant of the progesterone-containing Progestasert IUD. The first levonorgestrel-containing IUD was introduced in Finland in 1990 and was subsequently approved for use in Europe and several developing nations. The reservoirs of various models of this type of IUD contain anywhere from 46 to 65 mg of levonorgestrel and were designed to release 20 μg of levonorgestrel daily. The Mirena IUD was introduced in the United States in 2001. Also referred to as the levonorgestrel intrauterine system,
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Chapter 27 Modern Concepts in Intrauterine Devices the Mirena has a reservoir that contains 52 mg of levonorgestrel in the polyethylene T-shaped frame measuring 32 mm × 32 mm and has a monofilament string attached to the end of its vertical stem (see Fig. 27-2). The failure rate of this product is less than 0.1% per year. It has the added benefit of decreasing both menstrual bleeding and dysmenorrhea in most women.
Mechanisms of Action The two IUDs currently available in the United States, the copper-containing ParaGard and the levonorgestrel-containing Mirena, both work primarily by inhibiting fertilization and secondarily by inhibiting implantation.10,11 Because they work before implantation, IUDs are not considered to be abortifacients. Both IUDs share a foreign body mechanism of action, but each has a second mechanism of action related to the substance they release locally. Foreign Body Effect
Like earlier inert IUDs, both the ParaGard and Mirena IUDs produce a strong foreign body inflammatory reaction in the endometrium. The presence of the plastic T-shaped IUD causes the endometrial lining to release white blood cells, prostaglandins, and enzymes.12 In addition to making the endometrium unfavorable for implantation, this inflammatory reaction is toxic for sperm. As a result, IUD users have fewer sperm reaching the site of fertilization in the ampullary region of the fallopian tube.13 Based on studies of the earlier inert IUDs, it can be extrapolated that this foreign body reaction prevents pregnancy with a failure rate of approximately 20% per year. The addition of copper and progestin is responsible for further reducing the failure rate with modern IUDs to less than 1% per year. Copper Effects
The primary contraceptive effect of the copper released from the ParaGard IUD appears to be toxicity to sperm and oocytes before fertilization in various locations in the uterus and tubes. In the cervix, a high copper concentration in the mucus decreases both sperm motility and the ability of sperm to penetrate the mucus.14–16 Copper has the curious ability to cause the heads and tails of sperm to separate.17 In the uterine cavity, copper ions enhance the inflammatory intrauterine response in the endometrium, adding to the spermicidal effect.10 In the fallopian tubes, high copper concentrations interfere with transportation and function of both sperm and oocytes.18 When the uterine tubes of women with a copper IUD in place were flushed, only half as many oocytes were present compared to controls, and none of these oocytes showed normal development.19 Copper also appears to affect fertilization and implantation. Although copper IUDs do not prevent ovulation, oocyte fertilization is decreased by half and those embryos that do form rarely implant.12,13 Further evidence of the preimplantation nature of copper IUD effects is the finding that serum levels of β-human chorionic gonadotropin (hCG) are uniformly undetectable in these women.20 To date, there has been no evidence to indicate that copper IUDs act as abortificients after implantation.
Levonorgestrel Effects The levonorgestrel in the Mirena IUD has some contraceptive effects that are similar to copper but other effects that are unique. In the cervix, levonorgestrel, like copper, decreases sperm motility and the ability of sperm to penetrate the mucus, apparently by increasing mucus viscosity.11 This appears to be both a direct effect of the progestin on cervical mucus production as well as an indirect effect through alterations in ovarian function. Levonorgestrel affects ovarian function.21 Part of the effect on cervical mucus appears to be secondary to the ability of levonorgestrel to suppress ovarian estrogen production. In some women, follicular development and ovulation is diminished, although most women remain ovulatory after the first year of use.22 Like copper, levonorgestrel also prevents fertilization by inhibiting transport of the sperm through the fallopian tube. In contrast to copper, levonorgestrel prevents implantation by directly suppressing the endometrial lining. In addition to foreign body reaction, endometrial biopsies from levonorgestrel IUD users reveal atrophic endometrial glands and decidualized stroma consistent with a progestin effect.23 As with copper IUDs, evidence of the ability of levonorgestrel IUDs to prevent implantation is the finding that serum levels of β-hCG is uniformly undetectable in these women.24 Once again, there has been no evidence to indicate that levonorgestrel IUDs act as abortificients after implantation.24
Contraceptive Efficacy of Modern IUDs The annual and long-term pregnancy rates of the copper and levonorgestrel IUDs are among the lowest for available reversible contraceptive measures (Table 27-1). The 1-year pregnancy rate for the copper-containing ParaGard IUD is approximately 0.5 per 100 women.12 The 1-year pregnancy rate for the levonorgestrelcontaining Mirena IUD is 0.2 per 100 women, but the overall 5-year pregnancy rate averages 0.7 per 100 women.25 These pregnancy rates do not appear to be affected by parity. In practice, the cumulative pregnancy rates for both IUDs are impressively low. In a clinical study of use of these IUDs by 4000 women, the World Health Organization (WHO) reported the cumulative pregnancy rate for the Mirena IUD after 6 years to be only 0.6%, which was significantly lower than the rate for the ParaGard IUD, 2.0% (Table 27-2).26
Use of Copper-containing IUDs for Emergency Contraception Placement of the copper-containing ParaGard IUD in women after unprotected sexual intercourse is relatively effective in preventing subsequent conception. When used in this way for emergency contraception, the ParaGard IUD is most effective when placed within 72 hours after intercourse, but is still effective when placed within 5 days. In a meta-analysis of 20 studies of emergency contraception, the ParaGard IUD, with a subsequent 0.1% pregnancy rate, was found to be more effective than the standard oral contraceptive regimen, which had a 1.5% pregnancy rate.27
Discontinuation Rates Discontinuation rates are important, because women who discontinue their birth control method for side effects are at high
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Section 4 Contraception Table 27-1 Contraceptive Failure Rate for Various Methods During the First Year of Typical and Perfect Use, and the Percentage Continuing Use at the End of the First Year72,73 Accidental Pregnancies Method
Typical Use
Women Continuing Use at One Year
0.5% 0.2%
0.5% 0.2%
78% 81%
Surgical Sterilization Tubal ligation Vasectomy
0.4% 0.1%
0.4% 0.1%
100% 100%
Hormonal Contraception Oral Contraception Estrogen and progestin Progestin-only Depot medroxyprogesterone Transdermal Patch
8% 8% 3% 8%
0.3% 0.3% 0.3% 0.3%
72% 68% 70% 68%
12% 21% 18%
3% 5% 6%
63% 56% 58%
Barrier Methods Male Condom (latex, no spermicide) Female Condom Diaphragm (with spermicide) Vaginal Sponge Nulliparous woman Parous woman Cervical Cap Nulliparous woman Parous woman Spermicide (gel, foam, suppository, or film)
18% 36%
9% 20%
58% 45%
18% 36% 21%
9% 26% 6%
58% 45% 43%
Natural Methods Withdrawal Natural family planning (calendar, temperature, cervical mucus) No contraceptive method
19% 20% 85%
4% 9% 85%
43% 67% −
Table 27-2 The Cumulative Six-year Probability of a Woman Discontinuing the Copper-containing ParaGard IUD and Levonorgestrel-releasing Mirena IUD26
Name
ParaGard (copper)
Mirena (levonorgestrel)
Cumulative Pregnancy Rate Intrauterine pregnancy Ectopic pregnancy
2.0% 1.8% 0.1%
0.6% 0.6% 0.0%
Expulsion Complete expulsion Partial expulsion
1.7% 6.6%
3.0% 4.9%
Pelvic Inflammatory Disease Menstrual Reasons Amenorrhea Reduced bleeding Increased bleeding Pain
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Perfect Use
Modern Intrauterine Devices Copper-containing Levonorgestrel-containing
0.0%
0.3%
10.7% 0.6% 3.0% 7.0%
36.2% 23.8% 11.2% 5.6%
5.9%
5.2%
risk for pregnancy. In the first year, more patients continue using IUDs than any other reversible contraceptive method. Although studies of modern IUDs have shown general patient satisfaction and safety, the reported discontinuation rate after 7 to 8 years of use varies from 28% to 73%, depending on the population28–31 For both types of modern IUDs, menstrual reasons are listed as the most common side effect resulting in IUD discontinuation (see Table 27-2).26 For the ParaGard IUD, this was most commonly increased bleeding, whereas for the Mirena IUD, this was most likely amenorrhea or decreased bleeding. Because of the high rate of amenorrhea for the Mirena compared
to the ParaGard IUD (23.8 vs. 0.6%, respectively), the 6-year continuation rate was significantly lower for the Mirena (43.8%) compared to the ParaGard (66.6%).26 Pregnancies and pelvic inflammatory disease (PID) are very uncommon for both types of IUDs. Although the study described in Table 27-2 showed a higher cumulative pregnancy rate for ParaGard compared to Mirena (2.0% vs. 0.6%, respectively), a multicenter prospective 7-year randomized study of more than 7000 women reported equal pregnancy rates (0.2 per 100 womenyears) and PID rates (0.6 to 0.7 per 100 women-years) for both types of IUDs.28 Rates for both of these complications were highest in the first year after insertion.
Relative Cost Modern IUDs are among the most cost-effective contraceptive methods.32 When calculating the total cost of a method, an economic analysis must include the initial costs, including contraceptive medication or device plus the placement fee; costs of treating side effects (e.g., surgical complications, deep venous thrombosis, amenorrhea, or urinary tract infections); and the cost of unintended pregnancies. According to one analysis, over a 5-year period the coppercontaining ParaGard IUD was calculated to be the least expensive at only $540, whereas oral contraceptives cost approximately $1784 over this same time period.32 Although vasectomy and tubal ligation would certainly be less expensive over the entire reproductive life of a woman, surgical sterilization has the obvious disadvantage of limited reversibility. The extremely low initial costs of many nonmedical approaches are more than offset by the cost of unintended pregnancies.
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Chapter 27 Modern Concepts in Intrauterine Devices Return to Fertility After removal of an IUD for reasons other than PID, there is no measurable residual effect on fertility no matter how long the IUD was used.33 This is in contrast to depot medroxyprogesterone, where fertility is usually delayed a matter of months until the medication has been cleared from the woman’s system.34
NONCONTRACEPTIVE BENEFITS OF IUDS It has long been suspected that IUDs might have benefits other than contraception as a result of local effects on the uterus. Unexpected benefits of inert and copper-containing IUDs were the first to be recognized. Concurrent with the development of the first progestin-containing IUD, it was envisioned that effective administration of continuous high concentrations of progestins directly to the endometrium could have benefits other than contraception.
Inert and Copper-containing IUDs A reduced risk of endometrial cancer was an unexpected finding in women who used either inert or copper-containing IUDs.35 Multiple studies performed throughout the world suggest that the risk of endometrial cancer in IUD users is reduced by 30% to 50%. It has been proposed that IUDs exert their protective effect through local structural and biochemical changes in the endometrium that may decrease endometrial sensitivity to estrogen or increase sensitivity to progesterone. Some authors suggest that this association could be a reflection of selection bias, because inert and copper-containing IUDs are less likely to be used in women with menstrual abnormalities who may be at increased risk for endometrial cancer. However, the data appears convincing that the incidence of endometrial cancer is decreased in women who have used either an inert or coppercontaining IUD.
Levonorgestrel-containing IUD The levonorgestrel-containing Mirena IUD has been found to be an effective way to administer progestins locally to the endometrium while avoiding the systemic side effects and risks associated with oral, intramuscular, and transdermal progestins. In addition to contraception, this approach has been shown to be effective in treating a variety of gynecologic disorders, including menorrhagia and dysmenorrhea, and has been found to be effective in women taking either estrogen replacement therapy or tamoxifen for adjuvant breast cancer therapy. In many women with bleeding problems, the Mirena IUD has been used as an alternative to hysterectomy. Physiology
Continuous levonorgestrel exposure significantly suppresses the endometrium. Light microscopy shows that the endometrium becomes thin because of glandular cell atrophy and stromal cell decidualization. In addition, there is visible reduction in the size and number of endometrial blood vessels. Electron microscopy reveals that levonorgestrel causes thickening of the basal lamina between the endometrial epithelial and persistence of the complex intercellular junctions between the epithelial cells, which normally loosen around the time of implantation.36
Abnormal Uterine Bleeding and Dysmenorrhea
Excessive or too frequent uterine bleeding impairs the quality of life for many otherwise healthy women. After infection and uterine malignancies are excluded, the most common medical treatment for excessive uterine bleeding is progestin administration. Unfortunately, progestins given systemically do not always resolve these problems because of inconsistent effects on the uterus or because patients do not tolerate them because of systemic side effects or the risk of complications (including increased breast cancer). As a result abnormal uterine bleeding or dysmenorrhea remain some of the most common indications for hysterectomy in the United States.37 Excessive Menstruation
The Mirena IUD effectively decreases uterine bleeding in women with no demonstrable uterine pathology, regardless of parity. In normal women, the average menstrual blood loss is 30 to 40 mL. In women with a Mirena in place, the average menstrual blood loss is as little as 5 mL. More than 20% of Mirena users will have amenorrhea after the first year of use. This is in contrast to the copper-containing ParaGard IUD, for which the average menstrual bleeding is slightly increased to 40 to 50 mL. Controlled, randomized trials comparing treatment of heavy menstrual bleeding with hysterectomy versus medical therapy with the Mirena IUD have shown that hysterectomy is more effective in controlling menstrual bleeding, but the Mirena IUD appears to be equally beneficial in improving quality of life.38 Endometriosis-associated Dysmenorrhea
The Mirena IUD appears to be an effective treatment for dysmenorrhea associated with endometriosis. In this randomized, controlled study of 40 patients with laparoscopically diagnosed endometriosis, insertion of the Mirena IUD after laparoscopic surgery decreased the return of moderate to severe dysmenorrhea after 1 year to only 10%, compared to 45% in the control group.39 The effect on recurrence of endometriosis was not determined. Adjuvant to Estrogen Replacement Therapy
Menopausal women on estrogen replacement therapy appear to benefit from the use of the levonorgestrel-containing Mirena IUD. Although the use of the Mirena IUD with estrogen replacement is associated with bleeding during the first few months, after 1 year the majority of patients (73%) had no spotting or bleeding.40 Likewise, in a study of 40 postmenopausal women randomized to receive either transdermal estrogen and a Mirena IUD or daily oral estrogen plus the progestin norethisterone, the IUD group experienced more bleeding in the first 3 months, but both groups had an equivalent amount of bleeding for the remainder of the year.41 Approximately 80% of the postmenopausal women taking oral estrogen with a Mirena can be expected to have amenorrhea within a year of starting therapy. Adjuvant to Tamoxifen Therapy
Therapy for breast cancer with the selective estrogen receptor modulator tamoxifen is associated with an increased risk of endometrial hyperplasia, polyps, and carcinoma. A randomized, controlled study of the Mirena IUD in more than 124 women taking tamoxifen for 1 year showed a uniform endometrial
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Section 4 Contraception decidualization and fewer polyps and fibroids in women with an IUD compared to controls.42 Unfortunately, the women using the Mirena IUD had excessive bleeding that often took 6 months or more to resolve. This study was too short to assess the effect of the Mirena IUD on breast cancer recurrence; thus, further studies need to be done to assess if there is any benefit to this regimen. Uterine Leiomyomata and Menorrhagia
The Mirena IUD is not as effective in treating menorrhagia related to uterine leiomyomata. In a study of 19 women with menorrhagia secondary to uterine leiomyomata, over the 12 months after a Mirena IUD was placed, subjective menstrual blood loss decreased.43 However, 14 of these 19 women had persistent menorrhagia, and the average hemoglobin dropped from 10.9 g/dL to 9.9 g/dL during this same period. At the time of IUD insertion, these women’s enlarged uteruses measured an average of 13 cm, and it was hypothesized that the amount of progestin was inadequate to produce endometrial atrophy because of increased endometrial surface area. Larger studies will be required to determine the efficacy of the Mirena IUD in women with leiomyomata.
usually occurs within the first 3 months of use before complete decidualization of the endometrium. The addition of oral estrogen does not speed up the resolution of these symptoms and could possibly delay the decidualization process. After the first 3 months, most Mirena IUD users will have decreased menstrual bleeding, with the average menstrual bleeding decreasing from 35 mL to 5 mL per cycle, and more than 20% of these women will have amenorrhea.37 It is important to prepare women for this possibility because up to 4% of Mirena IUD users will request removal of their IUD due to amenorrhea. Bleeding abnormalities other than amenorrhea are more common with the copper-containing ParaGard IUD. In some studies, as many as 2% of ParaGard users discontinued their IUD due to bleeding abnormalities. Usually, this bleeding will be the result of unrelated anovulation or chronic endometritis. However, in women using an IUD over age 40, more than 10% of cases of abnormal uterine bleeding will be related to endometrial hyperplasia.47 Consequently, endometrial biopsy should be performed in IUD users over age 40 presenting with abnormal uterine bleeding.
Pregnancy
IUD SIDE EFFECTS Dysmenorrhea and Increased Menstrual Flow The levonorgestrel-containing Mirena IUD is associated with decreased dysmenorrhea and flow. In contrast, the coppercontaining ParaGard IUD still results in dysmenorrhea and increased menstrual flow in many patients, although it represents an improvement compared to larger inert IUDs.44 Physiologically, copper ions increase endometrial inflammation and prostaglandin production, resulting in both dysmenorrhea and increased flow. Although use of oral nonsteroidal anti-inflammatory drugs (NSAIDs) often ameliorates these side effects, 5% to 15% of patients request removal of the ParaGard IUD as a result of these side effects.
Hormonal Side Effects The progestins released from the levonorgestrel-containing Mirena IUD have no known systemic effects. However, these progestins do alter ovarian folliculogensis for as long as 12 months after insertion. As a result of these changes in ovarian function, some patients complain of headache, nausea, mood changes, mastalgia, acne flareup, and irregular bleeding. The Mirena IUD also causes a temporary increase in functional ovarian cysts in 12% of users, which is attributed to a decrease in follicular atresia.45 Expectant management is recommended for both the hormonal symptoms and the ovarian cysts, because both of these problems will resolve spontaneously within 3 to 6 months. Fortunately, the Mirena IUD does not appear to alter or inhibit ovulation after the first year of use.46
Irregular Bleeding
410
Irregular bleeding occurs in some patients using either the levonorgestrel-containing Mirena IUD or the copper-containing ParaGard IUD. For the Mirena IUD, this irregular bleeding
Pregnancy is an uncommon complication for women using modern IUDs. The pregnancy rate for women while using an IUD is approximately 1.26 per 100 women-years for the coppercontaining ParaGard IUD and 0.09 per 100 women-years for the levonorgestrel-containing Mirena IUD. However, the correct management of women who become pregnant with an IUD in place remains important to minimize the risk to both mother and fetus. IUD Management with an Intrauterine Pregnancy
Intrauterine pregnancies that occur while using an IUD are at increased risk of both early and late complications. In the first trimester, approximately half of the intrauterine pregnancies that occur will end in spontaneous abortion. Although the Dalkon Shield was associated with an increased risk of septic abortion, the risk of this complication has not been reported to be increased by modern IUDs. Women who become pregnant with an IUD in place are also at risk for late pregnancy problems, including intrauterine growth reduction, premature delivery, and fetal demise. When pregnancy is diagnosed with an IUD in place, the first step is the immediate removal of the IUD, even if the patient ultimately desires termination. Based on studies of inert IUDs, immediate removal of the IUD can potentially decrease the risk of spontaneous abortion from 50% to 25%.48 Removal of the IUD also appears to reduce the risk of secondand third-trimester pregnancy complications.49 If the IUD cannot be removed because of a “lost” string, the risk of prematurity is as high as 37.5%. Unfortunately, attempts to remove a “lost” IUD using ultrasound guidance and intrauterine instrumentation further increase the risk of pregnancy loss.50 Ectopic Pregnancy
The absolute risk of having an ectopic pregnancy is much lower for women using an IUD than for women using no birth control. The ectopic pregnancy rate for women using the copper-containing
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Chapter 27 Modern Concepts in Intrauterine Devices ParaGard IUD is approximately 0.25 per 100 women-years, and for women using the levonorgestrel-containing Mirena IUD is 0.02 per 100 women-years. This is much less than the ectopic pregnancy rate in women using no contraception of 1.6 per 100 women-years. However, tubal pregnancies appear to be more likely to occur among IUD pregnancies than among women using oral contraceptives or barrier methods, because these methods are more likely to prevent ovulation or fertilization.51 In the past, progestin-containing IUDs were believed to increase the risk of ectopic pregnancy, theoretically because progesterone impairs cilia function in the fallopian tube. More than 20% of the pregnancies that occur with the Mirena IUD in place will be ectopic, compared to a rate of ectopic pregnancies of 2% in women using no birth control. However, the absolute rate of ectopic pregnancies is decreased in women using the Mirena IUD. Patients should understand that in the rare event of pregnancy with an IUD in place, an ectopic pregnancy must be excluded.
Pelvic Inflammatory Disease PID is probably the most feared complication associated with IUD use. The higher incidence of PID associated with the Dalkon Shield and its braided tailstring was apparently magnified by the increased prevalence of sexually transmitted diseases (STDs) in the 1970s. In the late 1970s and early 1980s the concern for association between IUDs and PID caused the use of IUDs in the United States to plummet from 2.2 million in 1982 to 0.7 million in 1988. Postinsertion PID
In women in the United States, the overall risk of PID for both the ParaGard and Mirena IUDs is 0.6 to 0.7 per 100 womenyears of use; these rates are highest in the first year after insertion.52 A worldwide study conducted by the World Health Organization (WHO) found that the risk of PID within 20 days after insertion was 10 in 1000 women-years, and the majority of these cases occur in women at high risk of PID who had multiple sexual partners.53 For a patient in a monogamous relationship, the incidence of PID from the insertion procedure is extremely low.52 In the absence of an STD, any case of PID that occurs within 20 days of IUD insertion is most likely to be due to contamination of the uterus with lower genital tract bacteria that cannot be cleared by the uterus. Even though IUDs are placed using aseptic technique, the uterine cavity is unavoidably contaminated with bacteria from the vagina or cervix during insertion. Unfortunately, the addition of prophylactic antibiotics has not been shown to be useful, at least in part because the background incidence is so low.54 Treatment of STDs in IUD users
Women found to have an STD while using an IUD can be safely treated with antibiotics without removing the IUD. The fact that they have an STD puts them at risk for subsequent PID; thus removing the IUD on diagnosis of an STD is reasonable. However, after appropriate counseling and informed consent, woman treated for an STD can continue to use an IUD if they desire.
Women diagnosed as having PID with an IUD in place should be cultured and immediately placed on appropriate antibiotics. The IUD should be removed, because this will significantly improve recovery rates. Although the WHO recommends waiting to remove the IUD until after antibiotics are initiated to decrease the risk of disseminating the infection, there is no evidence to support the recommendation. Actinomyces
Actinomyces are gram-positive anaerobic bacilli characterized by filamentous growth and mycelia-like colonies that have a striking resemblance to fungi. These organisms, which are a part of the normal vaginal flora, can result in pelvic actinomycosis, a rare type of granulomatous PID that has an incidence of less than 0.001% of women discharged from the hospital.55 Actinomyces or Actinomyces-like organisms are detected on Pap smears only 0.13% of the time, and almost always in women using an IUD.56,57 It is important to know that the presence of Actinomyces on a Pap smear does not diagnose or predict pelvic actinomycosis. For this reason, it is recommended that the IUD should be left in place when Actinomyces are found on Pap smear in an asymptomatic woman.58 Antibiotics are not recommended because there is no evidence that they are of any value in preventing subsequent pelvic actinomycosis. The woman should be informed of the finding and instructed to return for any symptoms of pelvic infection and evaluated in 6 months. Subsequent Pap tests can be done at the normal interval. Should subsequent Pap smears show Actinomyces, removal and replacement of the IUD is a reasonable option. Alternative options include a repeated Pap test in 4 to 6 weeks and treatment with antibiotics for 2 weeks if still positive or removal of the IUD, antibiotics for 2 weeks, and then a repeated Pap smear. If pelvic actinomycosis is suspected in a women with PID symptoms such as abdominal pain, fever, vaginal discharge, or weight loss and has Actinomyces on Pap smear, her IUD should be removed, scraped for cytology, and sent for culture.58,59 The woman should receive an appropriate antibiotic treatment with intravenous penicillin G (10 to 20 million U/day) for 4 to 6 weeks until serial cultures confirm the absence of Actinomyces. In serious cases, metronidazole can be added to treat any concomitant anaerobic infection.60,61 Oral penicillin V (1 to 2 g, twice daily) is continued for 6 to 12 months after the intravenous antibiotics.
IUD INSERTION AND REMOVAL Patient Selection Ideal candidates for IUD use are those women who desire relatively long-term contraception and are at low risk for STDs. In the past, IUDs were selectively prescribed to parous woman who were relatively sure they did not want further pregnancy in an effort to minimize the potential effects of subsequent PID on future childbearing desires. Because it has become well established that IUDs do not increase the risk of PID compared to other forms of contraception and subsequent fertility is not decreased by IUD use, this precaution is no longer necessary. The current recommendation is that IUDs are best suited for women of any parity who are in a mutually monogamous relationship. Although the risk of PID does not appear to be
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Section 4 Contraception increased in IUD users, the occurrence of PID in IUD users continues to be problematic, because the IUD foreign body is usually removed for more effective treatment. Furthermore, both condoms and oral contraceptives might be more appropriate contraception for women at high risk of contracting an STD because they both appear to decrease the risk of PID. For these reasons, it is recommended that IUDs be recommended to patients who are at the lowest risk of contracting STDs. Another group of ideal IUD candidates are women who would benefit from their noncontraceptive benefits, regardless of their need for contraception. During the reproductive years, a levonorgestrel-containing IUD can be of some benefit to women with heavy or painful periods, especially in the presence of chronic iron deficiency anemia, and in women with bleeding disorders, such as Von Willebrand disease. After menopause, these IUDs can benefit women who need the protective effects of progestins on the endometrium when using unopposed systemic estrogens. A final group of candidates for an IUD are those for whom pregnancy would present a significant risk and thus need highly effective contraception, but other methods such as oral contraceptives are contraindicated or have unacceptable side effects. This includes patients with cardiovascular conditions, such as hypertension, hyperlipidemias, stroke, ischemic heart disease, atrial fibrillation, and valvular disease, and in some women with chronic neurologic conditions such as epilepsy, depression, or severe migraines. Contraindications
IUD contraindications can be divided into conditions that are either exacerbated by the presence of an IUD or make IUD placement difficult (Table 27-3). Obviously, known or suspected pregnancy is an absolute contraindication, because IUD placement will usually, but not predictably, terminate the pregnancy and put the patient at increased risk for pregnancy complications. Another absolute contraindication is a recent or current gynecologic infection, because the placement of a foreign body in the uterus might make treatment more difficult, in some cases resulting in an ascending infection. This includes cervicitis, pelvic tuberculosis, and endometritis within the previous 3 months, including postpartum endometritis. IUD insertion can be performed in the presence of cervicitis or vaginitis once chlamydia and gonorrhea have been excluded. Table 27-3 Contraindications for IUD Placement Conditions Exacerbated by IUD Pregnancy Recent gynecologic infection Puerperal sepsis Postseptic abortion Pelvic inflammatory disease Sexually transmitted disease within the past 3 months Unexplained vaginal bleeding Breast cancer (for Mirena only)
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Conditions That Make IUD Placement More Difficult Distorted uterine cavity Congenital anomalies Fibroids that distort the endometrial cavity Malignancy Gestational trophoblastic disease Cervical cancer Endometrial cancer
Human Immunodeficiency Virus
Patients infected with human immunodeficiency virus (HIV) represent special cases. Fortunately, there has been no evidence to suggest that an IUD increases viral shedding or HIV transmission.62,63 A concern that HIV patients with decreased immunity might be at higher risk of PID near the time of insertion is unfounded. However, it is recommended that IUDs be placed in patients with AIDS only after antiviral therapy has been started. If a patient with an IUD develops an HIV infection, the IUD does not need to be removed, but the patient should be counseled and closely monitored for a pelvic infection. An HIV-positive woman with an IUD who develops AIDS may continue to use this contraception but should be closely monitored for infection. A final group of absolute contraindications to IUD use are known or suspected uterine malignancies, including cervical cancer, gestational trophoblastic disease, and endometrial cancer. The concern with these patients is the higher risk of perforation with placement. Relative contraindications for IUDs are related to sexual practices and anatomic abnormalities. Patients not in a monogamous relationship are not ideal IUD candidates, because they are at increased risk of acquiring an STD. Likewise, patients with a history of STDs or PID are less than ideal IUD candidates unless their sexual risk factors have significantly improved. Relative contraindications for anatomic considerations include uterine anomalies and leiomyomata, both of which can distort the uterine cavity. These conditions can make placement of IUDs difficult, resulting in a higher risk of perforation and subsequent expulsion. Certainly, some patients with these conditions might find an IUD to be their best contraceptive choice, and the levonorgestrel-containing IUD has been found to decrease leiomyomata-associated menorrhagia. In several conditions, the theoretical risk of systemic levonorgestrel absorption makes the use of the Mirena IUD relatively contraindicated. Probably the greatest concern is in patients with breast cancer, because even undetectable absorption could potentially cause stimulation of hormonally sensitive tumors. The Mirena IUD is relatively contraindicated for a similar rationale in patients with active hepatitis, cirrhosis, and benign or malignant liver tumors. It is not clear why the manufacturers consider a history of acute deep venous thrombosis or pulmonary embolism to be relative contraindications; progestins, including levonorgestrel, have not been shown to exacerbate these conditions. Cholelithiasis is not a contraindication for IUD use. Copper-containing IUDs are reasonable alternatives for conditions that may be adversely affected by steroid hormones. Conversely, the rare Wilson’s disease, in which copper is sequestered by the liver, is an absolute contraindication to the copper-containing ParaGard IUD but not to the Mirena IUD. Certainly, in cases where the benefits outweigh these theoretical risks, IUDs should be considered.
Preplacement Examination and Laboratory Evaluation A routine pelvic examination should be performed before IUD insertion to determine uterine position and size and to detect any previously unidentified abnormalities. A Pap smear should be obtained and cervical abnormalities evaluated and treated before IUD placement. In areas with a high background risk of
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Chapter 27 Modern Concepts in Intrauterine Devices STDs, it is reasonable to exclude gonorrhea and chlamydia infections before placement. A pregnancy test is also a reasonable precaution in any patient who is not using highly effective contraception.
Premedication Pain Medicine
Patients should be given NSAIDs before IUD insertion. Although most patients will experience only mild discomfort with IUD insertion, up to 5% experience moderate to severe pain. In addition, approximately 1% of women will experience vasovagal reactions or cervical laceration. These problems all appear to be more common in women of low parity.
Ideally, the IUD should be inserted within 10 minutes of delivery of the placenta but can be delayed up to 24 hours. Expulsion increases from 9% when the IUD is placed immediately after delivery to 37% when placed between 24 and 48 hours after the delivery. Insertion is not recommended more than 48 hours after delivery, because both perforation and expulsion rates are unacceptably high.64–66
Insertion Techniques Interval Insertion
The routine use of prophylactic antibiotics at the time of IUD placement to decrease the chance of PID is not recommended, because they have not been found to be effective.54 In women at low risk of sexually transmitted infection, the risk of PID is negligible after IUD insertion, with or without the administration of prophylactic antibiotics. Likewise, the use of prophylactic antibiotics to prevent subacute bacterial endocarditis at the time of IUD placement is not recommended in patients with mitral valve prolapse, because bacteremia is not detectable when placing IUDs in the absence of pelvic infections. Prophylactic antibiotics are not recommended for patients at high risk of developing endocarditis because of significant underlying valvular heart disease, including patients with pulmonary hypertension, atrial fibrillation, or a history of subacute endocarditis.
After explaining the procedure to the patient and responding to her questions and concerns, a bimanual pelvic examination and speculum examination are performed to determine the size, position, consistency, and mobility of the uterus and to identify any tenderness, which might indicate infection. The cervix is cleaned with a water-based antiseptic solution to minimize the risk of infection after insertion. A tenaculum is usually used to steady the cervix and align the endocervical canal with the uterine cavity. The uterus is sounded slowly and gently to determine the depth and direction of the uterine cavity. A notouch technique is used to load the sterile packaged IUD in the inserters while both IUD and inserter are still in the sterile packaging. The IUD is placed high in the uterine fundus using the withdrawal method. The inserter tube containing the IUD is carefully and slowly inserted up to the uterine fundus to the depth indicated by sounding. The tube is withdrawn to the end of the inner rod (or plunger) while the rod is held steady. Then the tube and rod are withdrawn together. Finally, the threads are cut with scissors about 2 to 3 cm from the external os.
Timing of Insertion
Postpartum Insertion
Prophylactic Antibiotics
Interval Insertion
In patients who have never been pregnant or those at least 6 weeks postpartum, IUD insertion during the first half of the cycle appears to offer several advantages. Insertion at the time of menses ensures that the patient is not pregnant but increases the risk of expulsion during the first 2 months of use. Insertion on day 12 through 15 of the cycle decreases the risk of expulsion and results in fewer removals in the first 2 months for pain, bleeding, and accidental pregnancy. Insertion in the second half of the cycle is possible but is not recommended because a negative pregnancy test at this time cannot exclude a very early pregnancy. Immediately after an induced or spontaneous first-trimester abortion, an IUD can be inserted as long as there is no sign of infection (i.e., septic abortion). After second-trimester pregnancy losses, an IUD can be placed, but this should be done by a clinician with experience in postpartum IUD placement in the correct fundal location. Alternatively, the clinician may choose to wait until 6 weeks after the abortion. Postpartum Insertion
Postpartum IUD insertion, although rare in the United States, is a common technique is in many parts of the world. There is no increased risk of bleeding, infection, or perforation with this approach, but the risk of expulsion is increased, ranging from 9% to 37%, compared with 13% for insertions delayed until 6 weeks postpartum.64–66
Immediately after a second- or third- trimester delivery, the IUD is inserted manually or with ring forceps high in the fundus. Lower insertion or insertion more than 24 hours after delivery increases the expulsion rate. An IUD can be placed at the time of cesarean delivery through the incision; this technique results in a lower expulsion rate compared to insertion after vaginal delivery. Because the IUD is a foreign body, it should not be inserted in women at increased risk of infection due to prolonged labor, prolonged rupture of membranes, or chorioamnionitis. When inserted in the fundus immediately after delivery, the 12-cm string of the ParaGard IUD will not be visible protruding through the cervix. In contrast, the 90-cm string of the Mirena IUD will usually be visible. In either case, the string can be cut to the appropriate length at the 6-week checkup as needed. If the string is not visible, proper IUD position should be determined by ultrasound to exclude expulsion. Retrieval of a “lost” string is discussed under Complications of Removal and Location in this chapter.
IUD Removal An IUD can be removed at any time during the menstrual cycle. To remove an IUD, the strings are grasped with ring forceps and slow, gentle traction is applied. The strings are pulled outward through the vagina until the IUD is expelled. Up to 2% of attempted IUD removals will prove to be difficult. If the IUD does not come out easily, a tenaculum can be used to align the cervical canal and uterine cavity. If removal
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Section 4 Contraception is still difficult, an attempt can be made to dilate the cervix, or the patient can be scheduled to return during menstruation, when the cervix is usually softer.
COMPLICATIONS OF REMOVAL AND LOCATION Missing Strings Sometimes the strings are not visible protruding through the cervix or break during removal. In many cases, the strings will be found within the cervical canal by probing with a cottontipped applicator or a narrow forceps. If this fails, either the strings have retracted into the uterine cavity or the IUD is no longer in the uterine cavity because it has perforated the uterine wall or has been unknowingly expelled. In a 2003 review of misplaced IUDs, 80% were found in the uterine cavity and 15% in the cervical canal, 10% had been expelled, and 5% were located in the peritoneal cavity.67 Keep in mind that retraction of the IUD strings into an enlarging uterus can be the first sign of pregnancy. For this reason, it is important to both exclude pregnancy and verify that the IUD is within the uterine cavity before blindly exploring the uterine cavity. If the patient is not pregnant and the IUD is found within the uterus with vaginal ultrasound, it does not have to be removed just because the strings are not visible. The IUD is no less effective, but it can no longer be verified as present by the patient feeling the string or seen by the clinician on pelvic examination. An IUD hook can be used to remove an IUD with missing strings (Fig. 27-3). This instrument is gently placed through the cervix into the fundus and rotated 180 to 360 degrees. In many cases, the IUD hook will loop around the vertical stem of the IUD and literally hook the lowest portion of the stem that broadens into a ball tip. The IUD can then be removed through the cervical os. If an IUD hook is not available, alligator forceps or uterine packing forceps can be introduced into the endometrial cavity to grasp the IUD. Ultrasound guidance can be helpful in difficult cases. If more than gentle force is required, the IUD may be embedded in the wall of the uterus and will have to be removed using operative hysteroscopy.
Expulsion Uterine contractions can cause partial or complete expulsion of an IUD any time after insertion. Most expulsions occur in the first year, especially the first 3 months after insertion. Over a 5-year period, the overall expulsion rate for both the Mirena and
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Figure 27-3
IUD hooks.
ParaGard IUDs is approximately 5% to 7%. Women at higher risk for expulsion include those who are younger, have lower parity, or have painful or heavy menstruation. Expulsion may be asymptomatic or accompanied by symptoms of pelvic pain or excessive bleeding or spotting. Because undetected partial or complete expulsion can result in unplanned pregnancy, women with IUDs should check for the IUD strings to make sure that the device is in the proper place on a regular basis. When incomplete expulsion has made an IUD partially visible at the external os, the IUD is contaminated and should be removed. Although no study has addressed this question, it seems reasonable to wait at least one cycle to insert a new IUD if the patient desires.
Perforation Placing a 3-cm long plastic T into the cavity of a relatively thickwalled uterus is a blind technique that depends completely on tactile perception. The uterine cavity is unlikely to be exactly aligned with the cervical canal, and the uterine wall can be surprisingly thin, especially in the lower uterine segment. As a result perforation occurs because the sound or IUD is inserted too deeply or at the wrong angle, often unknowingly, even in the most experienced hands. Uterine perforation at the time of IUD insertion occurs in fewer than 3 in 1000 cases, and the risk is inversely related to clinician experience.68–70 Another risk factor for perforation is insertion of the IUD between 0 and 6 months’ postpartum. Uterine perforation remote from IUD insertion also occurs. When the perforation is in a different direction than the plane of insertion (e.g., the IUD stem is found perforating through the cervix), it can be assumed that uterine contractions attempting to expel the IUD have forced it through the uterine wall. When the perforation is through the uterus in the plane of insertion, it is likely to be the result of a partial perforation at the time of insertion. Less than 15% of perforations are recognized at the time of IUD insertion. In many cases, the only indication that an IUD has partially or completely perforated the uterus is missing IUD strings or difficulty when attempting IUD removal. In other cases, the woman will experience abdominal or pelvic pain or irregular bleeding. If attempts to locate the missing IUD sonographically are unsuccessful, X-ray should be used to determine the location of the IUD. Management
If the uterus is perforated while sounding before IUD insertion, the IUD should not be placed. The patient should be given antibiotics and warned of the signs and symptoms of infection. Symptomatic patients can be treated with observation or surgical exploration as indicated. When it is recognized that an IUD has perforated the uterus and is located intraperitoneally, it should be removed as soon as possible. This is especially important when the copper-containing ParaGard IUD is discovered within the peritoneal cavity, because copper ions produce a severe local inflammatory response. Most intra-abdominal IUDs can be retrieved laparoscopically. However, the patient should also be counseled that laparotomy may be necessary to remove the IUD or deal with intra-abdominal complications, such as omental adhesions or bowel perforation.
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PEARLS71 ●
●
●
IUDs prevent pregnancy by (1) prefertilization impairment of the function of the sperm and ova and (2) preventing implantation. IUDs are not abortifacients. IUDs do not increase the risk of PID after the first 20 days of use. Multiple sexual partners and high-risk behavior increase the risk of STDs and PID. IUDs decrease the risk of ectopic pregnancies. However, if a woman with an IUD becomes pregnant, the changes of it being ectopic are high, especially with the Mirena IUD.
●
●
●
● ●
IUDs do not decrease subsequent fertility. After removal of the IUD, women have a rapid return to fertility. The contraceptive efficacy of an IUD is comparable to a tubal ligation (<1% per year), and this method is reversible. IUDs require a single act of compliance for 5 to 10 years of contraception. IUDs are cost-effective. Copper-containing IUDs may be used for emergency contraception within 5 days of intercourse.
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23. Phillips V, Graham CT, Manek S, McCluggage WG: The effects of the levonorgestrel intrauterine system (Mirena) on endometrial morphology. J Clin Pathol 56:305–307, 2003. 24. Stanford JB, Mikolajczyk RT: Mechanisms of action of intrauterine devices: Update and estimation of postfertilization effects. Am J Obstet Gynecol 187:1699–1708, 2002. 25. Mirena (levonorgestrel-releasing intrauterine system) Prescribing Information. Montville, N.J., Berlex Laboratories, 2000. 26. Department of Reproductive Health and Research, World Health Organization: The intrauterine device (IUD)—worth singing about. Progr Reprod Health Res 60:1–8, 2002. 27. Trussell J, Ellertson C: Efficacy of emergency contraception. Fertil Contracept Rev 4:8–11, 1995. 28. Sivin I, Stern J: Health during prolonged use of levonorgestrel 20 μg/d and the copper TCu380Ag intrauterine contraceptive devices: Amulticenter study. Fertil Steril 61:70–77, 1994. 29. Ronnerdag M, Odlind V: Health effects of long term use of the intrauterine levonorgestrel-releasing system. A follow-up study over 12 years of continuous use. Acta Obstet Gynecol Scand 78:716–721, 1999. 30. Backman T, Huhtala S, Tuominen J, et al: Sixty thousand woman-years of experience on the levonorgestrel intrauterine system: An epidemiological survey in Finland. Eur J Contracept Reprod Health Care 6 (Suppl 1):23–26, 2001. 31. Backman T, Huhtula S, Blom T, et al: Length of use and symptoms associated with premature removal of the levonorgestrel intrauterine system: A nationwide study of 17,360 users. BJOG 107:335–339, 2000. 32. Trussell J, Leveque JA, Koening JD, et al: The economic value of contraception: A comparison of 15 methods. Am J Public Health 85:494–503, 1995. 33. Nelson A: The intrauterine contraceptive device. Obstet Gynecol Clin North Am 27:723–740, 2000. 34. Fotherby K, Howard G: Return of fertility in women discontinuing injectable contraceptives. J Obstet Gynaecol 6(Suppl 2):S110–S115, 1986. 35. Castellsague X, Thompson WD, Dubrow R: Intra-uterine contraception and the risk of endometrial cancer. Int J Cancer 54:911–916, 1993. 36. Pakarinen PI, Lahteenmaki P, Lehtonen E, Reima I: The ultrastructure of human endometrium is altered by administration of intrauterine levonorgestrel. Hum Reprod 13:1846–1853, 1998. 37. Andersson JK, Rybo G: Levonorgestrel-releasing intrauterine device in the treatment of menorrhagia. BJOG 97:970–694, 1990. 38. Marjoribanks J, Lethaby A, Farquhar C: Surgery versus medical therapy for heavy menstrual bleeding. Cochrane Database Sys Rev 2004, CD02839. 39. Vercellini P, Frontino G, DeGiorgi O, et al: Comparison of a levonorgestrel-releasing intrauterine device versus expectant management after conservative surgery for symptomatic endometriosis: A pilot study. Fertil Steril 80:305–309, 2003. 40. Suhonen SP, Allonen HO, Lahteenmaki P: Sustained-release estradiol implants and a levonorgestrel-releasing intrauterine device in hormone replacement therapy. Am J Obstet Gynecol 172:562–567, 1995.
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57. Pearlman M, Frantz AC, Floyd WS, et al: Abdominal wall Actinomyces abscess associated with an intrauterine device: A case report. J Reprod Med 36:398, 1991. 58. Fiorino AS: Intrauterine contraceptive device-associated actinomycotic abscess and Actinomyces detection on cervical smear. Obstet Gynecol 87:142–149, 1996. 59. Traynor RM, Parratt D, Duguid HLD, Duncan ID: Isolation of actinomycetes from cervical specimens. J Clin Pathol 34:914–916, 1981. 60. Persson E, Holmberg K, Dahlgren S, Nilsson L: Actinomyces israelii in the female genital tract. Acta Obstet Gynecol Scand 63:207–216, 1984. 61. Peipert JF. Actinomyces: Normal flora or pathogen? Obstet Gynecol 104:1132–1133, 2004. 62. Bonacho I, Pita S, Gome-Besteiro MI: The importance of the removal of the intrauterine device in genital colonization by actinomyces. Gynecol Obstet Invest 52:119–123, 2001. 63. Richardson BA, Morrison CS, Sekadde-Kigondu C, et al: Effect of intrauterine device use on cervical shedding of HIV-1 DNA. AIDS 13:2091–2097, 1999. 64. European Study Group on Heterosexual Transmission of HIV: Comparison of female to male and male to female transmission of HIV in 563 stable couples. BMJ 304:809–813, 1992. 65. Finger WR: IUD insertion timing vital in postpartum use. Network 16:21–24, 1996. 66. Grimes D: Timing of IUD insertion. Contracept Rep 9:6–8, 1998. 67. Grimes D, Schulz K, van Vliet H, et al: Immediate post-partum insertion of intrauterine devices. Cochrane Database Sys Rev 2004, CD02069. 68. Barsaul, M, Sharma N, Sangwan K: 324 cases of misplaced IUCD—a 5-year study. Trop Doct 33:11–12, 2003. 69. Harrison-Woolrych M, Ashton J, Coulter D: Uterine perforation on intrauterine device insertion: Is the incidence higher than previously reported? Contraception 67:53-56, 2003. 70. Caliskan E, Öztürk N, Dilbaz BÖ, Dilbaz S: Analysis of risk factors associated with uterine perforation by intrauterine devices. Eur J Contracep Reprod Health Care 8:150-155, 2003. 71. Harrison-Woolrych M, Ashton J, Coulter D: Uterine perforation on intrauterine device insertion: Is the incidence higher than previously reported? Contraception 67:53-56, 2003. 72. Espey E, Ogburn T: Perpetuating negative attitudes about the intrauterine device: Textbooks lag behind the evidence. Contraception 65:389-395, 2002. 73. Trussell J, Hatcher RA, Cates W, et al: Contraceptive efficiency. Contraceptive Technology Update 18:13, 2004. 74. Sonnenberg FA, Burkman RT, Speroff L, et al: Cost-effectiveness and contraceptive effectiveness of the transdermal contraceptive patch. Am J Obstet Gynecol 192:1-9, 2005.
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28
Surgical Sterilization Thomas G. Stovall and Erin J. Saunders
INTRODUCTION Procedures for performing sterilizations have become much more prevalent in recent years. Millions of couples have opted for sterilization to control their fertility, making it the most frequently used method of contraception in the United States. The demand for female sterilization is dramatically increasing, and it is now the third most common surgical procedure performed on females in the United States. Tubal sterilization is a relatively simple procedure. It is a safe, extremely effective method of permanent sterilization. This procedure may be performed on an outpatient or inpatient basis, using either an abdominal, vaginal, hysteroscopic, or laparoscopic approach, and may be performed as either a postpartum or interval operation. The choice of procedure depends on the facilities available, timing, and the experience of the surgeon.
sterilization except for gynecologic malignancy or gynecologic disease that requires hysterectomy or bilateral oophorectomy. Certain circumstances require specific mention. For example, if the patient has known extensive intra-abdominal adhesions, the potential for intraoperative morbidity may be so great as to consider another form of contraception. For the patient with a severe medical problem, it is probably advisable to consult with a specialist in the particular disease-related area or a maternal medicine specialist to determine exactly how pregnancy would affect the condition in question. Often, patients have been told by a well-meaning healthcare provider that pregnancy is contraindicated when in fact it is not. The family of a severely mentally retarded patient may request sterilization, but these are special circumstances that require discussion with the family and most often require a second opinion, an ethics committee recommendation, and, at times, a court order.
HISTORY
Informed Consent
The first female sterilization in North America was performed in 1880 by S.S. Lungren of Toledo, Ohio and was done at the time of cesarean section. For the next few decades, all tubal sterilizations were performed at the time of laparotomy as a concurrent procedure or at the time of cesarean section because the risk of mortality was too high to perform this operation for sterilization alone. Sterilization became better accepted with the advent of the Pomeroy method of tubal occlusion, which could be accomplished through a small incision. In the 1970s tubal sterilization became widespread due to the introduction of minilaparotomy and laparoscopy as methods. Anderson1 is credited with performing the first laparoscopic electrocoagulation procedure in the United States in 1937. Steptoe2 in 1967 reported the first large series of laparoscopic sterilizations, and Wheeless3 in 1973 reported the first singlepuncture laparoscopic technique. These procedures allowed for interval surgery, surgery without hospital stay, reduced recovery time, less morbidity, and better cosmetic result.4 Sterilization is now the most commonly used method of family planning in the world.
PREOPERATIVE EVALUATION Tubal sterilization should be available to any woman who desires permanent sterilization, assuming that she has proper informed consent (Table 28-1) and adequate knowledge regarding the procedure. The procedure should be considered purely elective. There are virtually no absolute contraindications to tubal
Because most methods of sterilization are designed to be permanent, proper patient counseling and informed consent are important. The decision for sterilization should be made on an entirely voluntary basis after appropriate counseling on risk, benefits, and alternatives. Various materials are available to assist the physician in counseling the patient. The American College of Obstetricians and Gynecologists (ACOG) distributes a pamphlet that discusses different techniques of sterilization as well as alternative methods for contraception. For couples desiring permanent sterilization, vasectomy should always be discussed because vasectomy is associated with fewer complications than tubal sterilization. When counseling the patient on the benefits of sterilization, it is important to include that all methods are extremely effective, are permanent, and have a low failure rate.5 Risks of the female sterilization procedure include risk of anesthesia, operative surgical risks, and the 1% to 3% risk of failure with an increased risk of ectopic pregnancy. It should be remembered that patients
Table 28-1 Elements of Informed Consent for Sterilization Review of alternative methods of permanent sterilization (e.g., vasectomy) Indication that the procedure is considered permanent Review of failure rate of procedure Description of the planned operative technique Discussion of potential surgical risks
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Section 4 Contraception Table 28-2 Factors That Have and Have Not Been Associated with Regret After Sterilization Factors Associated with Regret
Factors Not Associated with Regret
Marital status change
Religion
Family stress (e.g., death of a child)
Socioeconomic level
Desire for additional children as the “baby” grows up
Education level
Post-tubal ligation syndrome symptoms
Low parity
Postpartum procedure
Decision made with husband’s approval
Sterilization before age 30
Interval procedure
whose sterilization will be federally funded must sign a special consent document and must be at least 21 years old. The patient’s husband is not required to give consent before the procedure is performed. Obviously, it is best if both partners have an understanding of the procedure as well as the benefits and potential risks of it. Thus, if a problem is encountered, the patient’s family is in a better position to deal with the problem. Sterilization Regret
Anywhere from 3% to 25% of women have regret about sterilization, and 1% to 2% of these patients actually seek tubal reversal. Some reasons for regret (Table 28-2) include change in marital status, death of a child, and wanting another child after other children have gotten older. Studies have shown that there is an increased risk of regret with change in marital status, age less than 30 at the time of sterilization, psychiatric history, postpartum sterilization, poor outcome with previous delivery, and ongoing marital, financial, health, or personal problems at the time of sterilization.5
TIMING Postpartum Sterilization
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Sterilization after delivery, during the patient’s postpartum hospital stay, is a convenient, effective, and efficient way to prevent future pregnancy. In the immediate postpartum period the uterus is enlarged to the level of the umbilicus, making it convenient to perform sterilization with a small 1- to 2-cm infraumbilical incision. Any of several techniques could be used. The longest period that the patient may wait before undergoing sterilization is controversial. In some circumstances, a delay of 12 to 24 hours may be needed to assess the infant’s condition, or delays secondary to staffing patterns or availability of anesthesia may be encountered. Studies done show no increased risk of morbidity if the sterilization is delayed for the first postpartum day.6,7 If it is not feasible during this time period to perform the sterilization, the patient should probably wait at least 6 weeks so that the uterine architecture will be back to normal. Before this time, the uterus may be enlarged, making laparoscopy more difficult, and there may be an increased risk of infection during the postpartum period. The patient who has a postpartum endometritis or has had premature rupture of the membranes, intrapartum fever, or manual placental removal is probably at
risk of a postsurgical infection. Therefore, it may be prudent for this patient to wait and undergo interval sterilization. If cesarean section is required and the patient desires sterilization, the two procedures should be performed concurrently. The addition of sterilization to cesarean section adds little to the operative risk of the procedure or to the postoperative morbidity. Also, performance of the sterilization procedure at the time of cesarean section or shortly after vaginal delivery allows the patient to recover from the two procedures simultaneously and therefore does not add to the patient’s hospitalization or convalescence period.
Interval Sterilization Interval sterilization after the immediate postpartum period should be delayed for 6 or 8 weeks. Most of these procedures are performed by laparoscopy and can be done using local, conduction, or general anesthesia. Performance of the procedure during the menstrual or proliferative phase of the cycle reduces the chance of pregnancy at the time of the procedure. However, if this is not practical, a sensitive urine or serum pregnancy test can be done on the day the procedure is performed. This too has been shown to decrease the risk of luteal phase pregnancy.8 Finally, sterilization can be performed in conjunction with other surgical procedures, such as cholecystectomy or plastic surgical procedures.
STERILIZATION METHODS More than 100 sterilization techniques have been described in the gynecologic literature. A discussion of the risks, benefits, technical aspects, and failure rates of each of these procedures is beyond the scope of this chapter. Therefore, only those techniques that are currently popular or are widely used are discussed. For the most part, interval sterilizations are performed by laparoscopy and postpartum sterilizations are done by minilaparotomy.
Madlener Technique The Madlener technique involves forming a loop of tube, of which a portion is crushed at the base of the loop and ligated with a nonabsorbable suture. Occlusion but not division of the lumen is achieved (Fig. 28-1). The end result is similar to the laparoscopic placement of a Silastic band for occlusion, as described in the section on the Falope ring in this chapter. Failures are often attributed to fistula formation at the ligature site. This technique is generally of historic interest only.
Irving Procedure The Irving procedure was introduced as a technique for ligation and division of the oviduct at the time of cesarean section. At the ampullary–isthmic junction, the proximal stump is buried within the myometrium and the distal stump is buried between the leaves of the broad ligament (Fig. 28-2). As the uterus undergoes involution postpartum, the buried proximal and distal ends of the tubes become compressed and eventually obliterated. This procedure takes longer and there is often more blood loss; however, the chances of tubal recanalization or pregnancy in the proximal stump are remote.
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Chapter 28 Surgical Sterilization Fimbriectomy Hemostat crushes segment
A
Loop of ampullary portion of tube elevated
The technique of fimbriectomy described by Kroener employs the ligation of the distal ampulla with two permanent sutures and division and removal of the tubal infundibulum (Fig. 28-5). The simplicity of this procedure accounted for its popularity, but fimbriectomy does not seem to have many advocates due to the availability of easier and much more effective procedures.
Vaginal Approach
Tubal segment is not removed surgically
B
Tube ligated over crushed area
Figure 28-1
Madlener technique for tubal ligation.
Pomeroy Method The Pomeroy method (Fig. 28-3) or its modifications are probably the most commonly used sterilization procedures today. A knuckle of tube is grasped at the midportion using a Babcock clamp. This segment of tube, approximately 2 cm in length, is then ligated at the base with an absorbable suture, preferably plain gut. This segment of tube is then excised and sent to the pathology laboratory for confirmation. The use of absorbable sutures allows the proximal and distal segments of the tube to separate, thus decreasing the risk of recanalization of the tube. The advantages to the Pomeroy method are that it is easy and quick to perform and highly effective. Its acceptance for both postpartum and interval sterilization is quite high.
Uchida Technique The Uchida technique is one of the more complex methods of tubal sterilization. It involves injection of a saline–epinephrine solution to the subserosal aspect of the tube, separating the muscular portion of the tube from the serosa. The serosa is then dissected off the muscular tube and a 5-cm segment of tube is excised while the proximal end is ligated and allowed to retract into the mesosalpinx. The mesosalpinx is then closed and a pursestring stitch is placed around the distal end to secure its position open to the abdomen (Fig. 28-4). A fimbriectomy may be added to this procedure to enhance effectiveness and prevent reanastomosis. The Uchida technique is more complicated than the other procedures but has been associated with very few failures.
Theoretically the vaginal approach (Fig. 28-6) seems ideal for safe and rapid tubal sterilization and has the advantage of avoiding an abdominal incision. However, the potential complications and complexity of the procedure prevent its widespread popularity. The possible complications from this procedure are cellulitis, hemorrhage, infection, cuff abscess, and bowel and bladder damage. Deep dyspareunia may also be a complication with some patients. The vaginal approach is particularly helpful in very obese patients or patients who have an umbilical hernia or previous umbilical hernia repair. Relative contraindications include multiple pelvic surgical procedures, endometriosis, known extensive pelvic adhesive disease, or uterine immobility on examination. The patient is placed in the dorsal lithotomy or knee-chest position. A right-angle or Dever retractor is used to expose the cervix, which is grasped on its posterior lip with a single-toothed tenaculum. The posterior cul-de-sac is exposed, and a colpotomy incision is performed using Mayo scissors. The tips of the scissors are placed in the peritoneal opening and spread to enlarge the incision. The anterior retractor is placed posterior to the cervix just inside the incision and is elevated. This maneuver results in retroflexion of the uterus. The fallopian tube is grasped with a Babcock clamp and brought into the operative field. The sterilization can be accomplished using tubal bands, electrocautery, or clips.9 However, the most common method described is the use of the Pomeroy technique.10 Once completed, the colpotomy incision is closed using interrupted figure-of-eight sutures or a single running suture of an absorbable suture material. Intraoperatively, the most common problem encountered is difficulty in exposing the fallopian tube. Placing the anterior retractor too deeply into the incision will antevert the uterus rather than cause uterine retroflexion. Suprapubic pressure can be used to facilitate uterine retroversion. Postoperatively, pelvic infection is the most serious potential complication after vaginal sterilization. Therefore, a single dose of prophylactic antibiotic should be administered approximately 30 minutes before the procedure.
Laparoscopic Sterilization Laparoscopic sterilization has become quite popular over the past few decades. This procedure provides superb visualization not only of the pelvic organs, but also of the entire abdominal cavity. Since the introduction of laparoscopy, women have had access to a safe, effective, and dependable method of sterilization. Unipolar Coagulation
Unipolar coagulation was the first method of laparoscopic tubal occlusion to achieve widespread use. The overall concept of the unipolar method involves the use of a grounded, high-voltage
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Fallopian tube is stabilized with Babcock clamp
Hemostat passed through avascular portion of mesosalpinx
A
Double ligation of tube
B
Tube divided
D
C Myometrial pocket created
E
Needle in base of pocket F
Proximal portion of tube buried in myometrium
G
Figure 28-2
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Irving procedure for tubal ligation.
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Chapter 28 Surgical Sterilization Figure 28-3 ligation.
Pomeroy method for tubal
Tube is grasped in the mid portion using the Babcock clamp
A
B Suture remains
Suture tied and cut
C
Segment of tube excised
D The suture dissolves and the tubal ends retract
generator that produces a coagulating current. Electrical energy is concentrated at a site grasped by operating forceps, with some lateral spread, and from this site, current travels through the patient’s body and exits at the return electrode (the grounding pad) on the patient’s skin. The laparoscopic unipolar procedure involves operative forceps, which are advanced through the operative site where the isthmic–ampullary portion of the tube is grasped and a 2- to 3-cm segment of tube is burned. Some surgeons combine electrocoagulation with transection or resection of a small part of the coagulated tube; however, the failure rate
is not improved and the risk of damage to the mesosalpinx and subsequent hemorrhage is increased. Although the unipolar method is still used, its popularity has declined due to the increased risk of thermal injury to the bowel from capacitance. Bipolar Coagulation
The bipolar form of electrocautery was next introduced. This differs from the unipolar method in that the operating forceps carries both the active and the return electrode. With this method, a cutting current is used at 25 watts of power, because
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A
B Incision
Figure 28-4 ligation.
Uchida technique for tubal
Muscular layer exposed
Subserosal injection of saline
C
A
Uterus retracted anteriorly Posterior vaginal fornix excised to enter peritoneal cavity
A Tube ligated at distal segment
B Perioneal cavity opened
C
D
B Tube double-ligated
Distal tube excised
E Segment (dome) excised
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Figure 28-5
Kroener fimbriectomy.
Figure 28-6
Vaginal tubal ligation.
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Chapter 28 Surgical Sterilization Figure 28-7
Electrocoagulation of fallopian tube segment
A
Laparoscopic tubal occlusion using bipolar electrosurgery.
B
3cm segment of tube dessicated
C
Figure 28-8
Laparoscopic tubal occlusion using rings.
A Falope ring applicator Grasping prongs
B Knuckle of tube drawn into tube applicator while band is advanced over it
C
Band in place of knuckle of fallopian tube
the coagulation current used with the unipolar method does not cause deep enough tissue damage to the tube and can lead to an intact lumen and increased failure rate. The isthmic portion of the tube is grasped and a 3-cm segment of tube is desiccated (Fig. 28-7). An ammeter is used to confirm proper coagulation through full-tissue thickness. This method prevents the spread of current to other organs and decreases the risk of bowel injury. This is the most common laparoscopic method for tubal ligation because it is technically the easiest, does not require mobile tubes, and is applicable with edematous tubes.
Falope Ring
The Falope ring, devised by Yoon, was the first nonthermal laparoscopic method for tubal occlusion. It involves drawing a 2-cm loop of tube 2 to 3 cm distal to the uterotubal junction into one of the two concentric cylinders of the ring applicator; then a Silastic band is passed over this loop, causing occlusion of the tube (Fig. 28-8). Because the Falope ring works by necrosis of the tissue in the band, local anesthesia is often applied to the tube to prevent postoperative pain.11 Although the failure rate of this procedure is low, this procedure is limited to
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Section 4 Contraception Figure 28-9 Laparoscopic tubal occlusion using clips. If the first one does not completely occlude the tube, a second clip should be applied.
A
Isthmic portion of fallopian tube grasped with clip applicator
B
Hulka clip closed over tube
C
Second clip only required if first clip does not apply well
nonedematous, mobile tubes. Occasionally, tubal transection and damage to the mesosalpinx can occur, which is why experienced clinicians should perform this procedure. Clips
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Hulka first reported the use of a spring clip for tubal sterilization in 1973. The Hulka clip, made of Lexan plastic, is maintained in its closed position by a gold-plated spring that diminishes peritoneal reaction. The interlocking plastic teeth compress the tube and obliterate the lumen of the tube. Placement is crucial with this clip. The clip is applied to the isthmic portion of the tube about 2 cm from the uterus and exactly at right angles to the tube. The jaws should be pressed against the tube with the tip of the clip extending onto the mesosalpinx, forming the characteristic envelope sign (Fig. 28-9). Like the Falope ring, this method works by necrosis; therefore, local anesthetic on the tube is preferable. This clip is most successful when placed on a normal tube because thickening of the tube, distortion, and adhesions may make application difficult and increase failure rates. One advantage to this method is that only a small portion of tube is damaged, which makes reanastomosis procedures more successful. A few years after the development of the Hulka clip, Filshie developed a clip with jaws of titanium and an inner cushion of silicone rubber. When the jaws close, the silicone rubber expands as tube necrosis occurs, causing complete occlusion of the tube and lumen. The Filshie clip is the easiest to apply due to the
grasping effect from the curve on the upper jaw. This clip, like the Hulka, is placed at a right angle on the isthmic portion of the tube 2 to 2.5 cm distal to the uterotubal junction, after application of local anesthetic on the portion of the tube to be obliterated. Because of its length, the Filshie clip can be placed on any type and shape of tube, including postpartum.12,13 Several randomized clinical trials compared the Hulka clip to the Filshie clip and showed that the failure rate with the Hulka is slightly higher (1.0 per 1000 for Filshie vs. 7.0 per 1000 for Hulka). This method also only destroys a small segment of tube, making tubal reversals easier.
Tubal Ligation Under Local Anesthesia With the popularity of tubal sterilization, finding ways to shorten operative time, hospital stay, and the cost of the procedure has become significant. One option to accomplish this goal is the introduction of tubal ligation under local anesthesia. This type of tubal ligation is ideal for patients without contraindications for local anesthesia, opportune for a nonoperating room setting, and ideal for patients who have a great fear of general anesthesia or have cardiac or pulmonary disorders preventing the use of general anesthesia. This approach is contraindicated in the anxious patient or obese patient who might require greater manipulation of abdominal organs. Local anesthesia should not be used by inexperienced surgeons due to its complexity.
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Chapter 28 Surgical Sterilization Advantages of this are that it avoids the risks associated with general anesthesia and decreases the cost of anesthesia. This is due to the fact that anesthesia time is decreased and recovery time is shortened with less postoperative nausea and vomiting with local anesthesia compared to general anesthesia. Disadvantages to local anesthesia are that the technique requires precise and gentle surgical manipulation with mild to moderate discomfort to the patient. Local anesthesia can also make the procedure more difficult for the surgeon because of the increased risk of patient movement during surgery and an increased need for close verbal contact between the surgeon and the patient during the procedure. Regimens
Local anesthesia regimens usually consist of three types of drugs: systemic agents that sedate the patient and block pain (midazolam, fentanyl, sufentanil, alfentanil), local analgesics that relieve pain at the incision site (bupivicaine),4 and systemic drugs that prevent nausea or disturbance of heart function (promethazine, atropine). After sedation the tubal ligation is performed as it would be under general anesthesia, paying close attention to the fact that the patient is awake, able to move, and can occasionally feel more sensation than under general anesthesia. Results of tubal ligation under local anesthesia are similar to those found under general anesthesia, with similar patient satisfaction, but less operating time. In a study by Mackenzie and colleagues that looked at postoperative effects of local anesthesia, they found that 21% of patients left the clinic within 4 hours of the operation and all patients had left after 7 hours. Ninety eight percent of patients were satisfied with the procedure under local anesthesia, and 94% would actually recommend the procedure to a friend.14
Hysteroscopic Sterilization Hysteroscopy is another method by which permanent sterilization can be achieved and is the newest method used for sterilization. One advantage of hysteroscopic sterilization is that it can be performed in the office setting under local anesthesia. Three approaches are being investigated at this time, and one procedure has received FDA approval. These include coagulation of the ostia, chemical sclerosis of the endosalpinx, and use of a plug to obstruct the tubal lumen. Electrocoagulation
Unipolar or bipolar electrocoagulation can occlude the tubes by introducing a conductive electrode into the ostia. Once the electrode is applied to the intramural portion of the tube, permanent occlusion should occur from electrocoagulation of the endosalpinx and the proximal layer of muscularis. Due to the difficulty involved, the FDA has not yet approved the method. Actually the ostia can only be identified 80% of the time and the procedure becomes blind once the probe is advanced into the tubal ostium, which could lead to bowel injury. The failure rate at present is far too high to approve this procedure for use (15% to 30%). Chemical Agents
The use of chemical agents has also been suggested to cause sclerosis of the endosalpinx. Many substances have been tried,
such as silver nitrate, formaldehyde, phenol, talc, quinacrine, and methylcyanoacrylate. Various methods of delivery have been studied, such as direct instillation to the tubes through hysteroscopic guidance, fluoroscopic-guided injection, blind injection, and loading the agent in an IUD type device. The latter two seem to be the most promising, with a closure rate between 88% and 94%, but still none have been approved by the FDA. Plugs
Three plugtype devices have reached human clinical trials, and the Essure device has been approved by the U.S. FDA (Fig. 28-10). The Essure procedure is a nonincisional surgical procedure that involves placing a small, flexible device called a micro-insert into each of the fallopian tubes. The micro-inserts are made from polyester fibers and metals (nickel–titanium and stainless steel).15 Once the micro-inserts are in place, tissue ingrowth occurs into the micro-inserts, blocking the fallopian tubes. Nickel allergy, recent pelvic infection, and possibly hydrosalpinx are contraindications to the procedure. A hysterosalpingogram must be done 3 months after the procedure to ensure and document tubal occlusion. Two separate studies of the safety and effectiveness of the Essure method have been conducted in women from the United States, Australia, and Europe. In the first study, 192 women relied on Essure for contraception for 1 year, 177 relied on Essure for contraception for 2 years, and 172 relied on Essure for contraception for 3 years. In the second study, 434 women relied on Essure for contraception for 1 year, 403 relied on Essure for contraception for 2 years and 21 for 3 years. None of the women who relied on Essure for contraception during the clinical trials became pregnant over the 1 to 3 years of follow-up.16
COMPLICATIONS Surgical Complications Tubal ligation carries the small risk associated with the surgical approach used, be it minilaparotomy or laparoscopy. In general, the major complication rate, defined as requiring a laparotomy, is less than 1%. Complications include anesthesia reactions, pelvic infections, and injury to intra-abdominal structures, including blood vessels, bowel, and bladder. Laparoscopic complications are described in more depth in Chapter 45.
Sterilization Failure Sterilization, although a reliable method of birth control, does have a failure rate that should be related to patients in counseling. Historically, the laparoscopic failure rate has been 0.1% to 0.4% compared to the Pomeroy method failure rate of 0.17% to 5%. These values are flawed by small study groups, methodology problems, and short follow-up (generally 1 to 2 years). This led to the U.S. Collaborative Review of Sterilization (CREST) study, which showed that sterilization has a higher failure rate than once thought. U.S. Collaborative Review of Sterilization (CREST) Study
This study was a multicenter, prospective study involving 10,685 women who had been sterilized who were then followed for 8 to 14 years to determine their probability of pregnancy.17–19 The techniques studied were silicone rubber rings, bipolar
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Hysteroscopic visualization of tubal ostia
A
10 years for bipolar electrocoagulation in young women age 18 to 27 is 5.4%; in those age 28 to 33, it is 2.1%; in those age 34 to 44, it is 0.6%. Postpartum salpingectomy had a 10-year failure rate of 1.1% in those age 18 to 27, 0.6% in those age 28 to 33, and 0.4% in those age 34 to 44. The higher failure rate than expected seen in this study has been accounted for in part by the fact that the centers used for these studies were teaching hospitals, and failure may be from poor technique and lack of experience. Therefore, to decrease the failure rate of tubal sterilization, proper technique should be used.
Delayed Complications Post-sterilization Syndrome
The catheter is pushed through the tubal ostia into the tube
B
Microinsert is placed in the tube and inserter withdrawn
C
Although tubal sterilization is a very effective method of contraception, some delayed complications may occur. Significant abnormal bleeding can occur after sterilization, leading to menstrual changes. This condition has been called poststerilization syndrome (pain, dysfunctional uterine bleeding, and premenstrual tension). In the United States 30% of women receiving tubal sterilization were taking oral contraceptive pills immediately before their procedure, and their menstrual changes may be attributed solely to oral contraception cessation. Multiple studies have been performed to look at the connection between sterilization and menstrual changes and have concluded that menstrual changes in the first 2 years after sterilization are not attributed to sterilization, thus negating the poststerilization syndrome theory.20 Whether menstrual changes that occur long after sterilization are attributable to the procedure is less clear. Researchers have investigated the levels of various hormones, mostly progesterone, to find a mechanism of endocrinologic changes after sterilization. At this time the issue remains unresolved because of the eight studies performed on this subject, four found decreased midluteal progesterone level and the other four did not. Hysterectomy Risk
Microinsert in tube with a small segment in the uterine cavity
D Figure 28-10
426
Hysteroscopic tubal occlusion using the Essure method.
electrocoagulation, postpartum partial salpingectomy, spring clip application, unipolar coagulation, and interval partial salpingectomy. Among these women, 143 sterilization failures occurred, with 32.9% being ectopic pregnancies. The cumulative 10-year probability of pregnancy was lowest after unipolar coagulation and postpartum partial salpingectomy, and highest with spring clip application. Results with the Filshie clip were not reported. In this study the sterilization failure rate after 10 years was 2%. The two most important variables were age at the time of sterilization and the technique used. The failure rate after
Studies have also been performed to look at the connection between hysterectomy and sterilization. The theory is that tubal sterilization could increase the risk of hysterectomy by increasing either the reality or the perception that a post-sterilization syndrome occurs. Alternatively, the fact that a woman has had a permanent sterilization procedure could affect decision making about further surgery. The fact that the increased risk of hysterectomy was concentrated among women sterilized at a young age suggests that any increased risk for hysterectomy after tubal ligation is not biologic in etiology but attributable to other factors, such as removal of fertility preservation as a factor in decision making. The currently available information regarding the effects of sterilization on menstrual patterns is controversial and conflicting. It is reassuring that no major adverse side effects are present at this time. Overall the benefits outweigh the risks of the procedure.
Sterilization Regret The occurrence of this adverse event is quite common. Young women under age 30 have the highest frequency, at approximately 20%.
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Chapter 28 Surgical Sterilization SUMMARY
●
With the desire for convenient methods of contraception, tubal ligation continues to be the most popular form of permanent sterilization in the United States. As seen in this discussion, there are many options for tubal ligation; the type of procedure used should be tailored to each individual patient’s needs. Female sterilization has progressed considerably and will continue to progress as easier, more efficient, and reversible methods are developed.
PEARLS ●
●
●
A vasectomy is safer and more effective than tubal sterilization. A tubal sterilization procedure is associated with increased risk of ectopic pregnancy. From 3% to 25% of women have regret about sterilization— 1% to 2% of these patients actually seek tubal reversal.
●
●
●
●
●
●
●
The most common reason to request a tubal reversal is change in marital status (i.e., a new partner). There is no increased risk of morbidity if the sterilization is delayed for the first postpartum day. The use of a unipolar coagulation system for sterilization necessitates that the electrical current go from the forceps and travel to the return electrode that is placed on the thigh. The use of bipolar energy allows the operating forceps to carry both the active and the return electrode. The method associated with the least tubal damage and the highest success with reversal is use of the clip. It is recommended that a hysterosalpingogram be done 3 months after the Essure procedure to assure and document tubal occlusion. Laparoscopic failure rate, according to the CREST study, was approximately 2%. The risk of laparotomy during laparoscopic tubal sterilization is approximately 2%.
REFERENCES 1. Anderson ET: Peritoneoscopy. Am J Surg 35:136–138, 1937. 2. Steptoe PC: Laparoscopy in Gynaecology. Edinburgh, E. and S. Livingston Ltd., 1967. 3. Wheeless CR Jr: Elimination of second incision in laparoscopic sterilization. Obstet Gynecol 39:134–136, 1972. 4. Soderstrom: Food and Drug Administration advisory panel on sterilization: Randomized, controlled trials of Filshie clip (1996). 5. Penney GC, Souter V, Glasier A, Templeton AA: Laparoscopic sterilization: Opinion and practice among gynacologists in Scotland. BJOG 104:71–77, 1997. 6. Black WP, Sclare AB: Sterilization by tubal ligation—a follow-up study. J Obstet Gynaecol Br Commonw 75:219–224, 1968. 7. Green LR, Laros RK: Postpartum sterilization. Clin Obstet Gynecol 23:647–659, 1980. 8. Lipscomb GH, Spellman JR, Ling FW: The effect of same-day pregnancy testing on the incidence of luteal phase pregnancy. Obstet Gynecol 82:411–413, 1993. 9. Hartfield VJ: Female sterilization by the vaginal route: A positive reassessment and comparison of four tubal occlusion methods. Austral NZ J Obstet Gynaecol 33:408–412, 1993. 10. Hartfield VJ: Day care Pomeroy sterilization by the vaginal route. NZ Med J 85:223–225, 1977. 11. Ezeh UO, Shoulder V, Martin JL, et al: Local anesthetic on Filshie clips for pain relief after tubal sterilization: A randomized double-blinded control trial. Lancet 34:82–85, 1995. 12. Filshie GM, Casey D, Pogmore JR, et al: The titanium/silicone rubber clip for female sterilization. BJOG 88:655–662, 1981.
13. Graf AH, Staudach A, Steiner H, et al: An evaluation of the Filshie clip for postpartum sterilization in Austria. Contraception 54:309–311, 1996. 14. MacKenzie IZ, Turner E, O’Sullivan GM, Guillebaud J: Two hundred out-patient laparoscopic clip sterilizations using local anesthesia. BJOG 94:449–453, 1987. 15. Valle RF, Carignan CS, Wright TC, and the STOP Preshysterectomy Investigation Group: Tissue response to the STOP microcoil transcervical permanent contraceptive device: Results from a prehysterectomy study. Fertil Steril 76:974–980, 2001. 16. Cooper JM, Canignan CS, Chen D, et al: Microinsert nonincisional hysteroscopic sterilization. Obstet Gynecol 102:59–61, 2003. 17. Hillis SD, Marchbanks PA, Tylor LR, Peterson HB, for the U.S. Collaborative Review of Sterilization Working Group: Higher hysterectomy risk for sterilized than nonsterilized women: Findings from the U.S. Collaborative Review of Sterilization. Obstet Gynecol 91:241–246, 1998. 18. Hillis SD, Marchbanks PA, Tylor LR, Peterson HB, for the U.S. Collaborative Review of Sterilization Working Group: Poststerilization regret: Findings from the U.S. Collaborative Review of Sterilization. Obstet Gynecol 93:889–895, 1999. 19. Hillis SD, Marchbanks PA, Tylor LR, Peterson HB, for the U.S. Collaborative Review of Sterilization Working Group: Tubal sterilization and long-term risk of hysterectomy: Findings from the U.S. Collaborative Review of Sterilization. Obstet Gynecol 89:609–614, 1997. 20. Peterson HB, Jeng G, Folger SG, Hillis SA, et al, for the U.S. Collaborative Review of Sterilization Working Group: The risk of menstrual abnormalities after tubal sterilization. NEJM 343:1681–1687, 2000.
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Section 5 Reproductive Imaging Chapter
29
Hysterosalpingography Jeffrey M. Goldberg
INTRODUCTION Hysterosalpingography (HSG) is a radiographic procedure used to image the uterine cavity and demonstrate tubal patency by injecting radiographic contrast media through the cervix (Fig. 29-1). Along with documentation of ovulation and semen analysis, HSG is one of the fundamental infertility tests. The technique is easy to learn and perform, is relatively low-cost, and has an acceptable radiation exposure and few complications. More than 200,000 HSG procedures are performed annually in the United States.1 In this chapter, the technique, risks, therapeutic effects, and alternative procedures are reviewed. Several examples of abnormal studies are also provided as an aid to interpreting HSG images. It is essential to be able to read the films, especially if the study was completed by someone other than the treating gynecologist.
HISTORY HSG was first performed in 1910 when Rindfleisch injected a bismuth solution transcervically followed by an abdominal X-ray. HSG has been the standard initial test for assessing the uterine cavity and fallopian tubes since Heuser used Lipiodol in 1925.2 Fluoroscopic control replaced static films in 1947.3 The procedure has remained essentially unchanged since then.
ACCURACY HSG should be considered a screening test; as such, it should have a high sensitivity so as not to miss the opportunity to treat an abnormality but with a low false-positive rate to prevent unnecessary additional testing and treatments. The accuracy of an HSG is highly dependent on technique and interpretation. The technical quality of the HSG is important to limit misinterpretations (i.e., eliminating air bubbles that may be confused with a polyp or myoma or using inadequate contrast volume or injection pressure to demonstrate tubal patency). In one study 50 HSG films were reviewed by five reproductive endocrinologists. There was considerable variability in the interpretation as well as the recommended clinical management.4 In another study, three reproductive endocrinologists and three radiologists reviewed 50 HSGs on two occasions. The intrareader and inter-reader reliability was high for the detection of normal uterus and tubes, as well as tubal obstruction, but low for the detection of hydrosalpinges, uterine adhesions, pelvic adhesions, and salpingitis isthmica nodosa. Clinicians more reliably diagnosed
hydrosalpinges and tubal obstruction; radiologists more reliably detected salpingitis isthmica nodosa and uterine adhesions.5
Diagnosing Uterine Cavity Abnormalities HSG has a high sensitivity but a low specificity for the diagnosis of uterine cavity abnormalities.6 HSG and diagnostic hysteroscopy performed on 336 infertile women showed that HSG had a sensitivity of 98% but a specificity of only 35% due to difficulties distinguishing between polyps and myomas. False-negative results were mild intrauterine adhesions of doubtful clinical significance.7 Thus, HSG fulfills the requirements as a good first-line screening test for revealing abnormalities of the uterine cavity, although any abnormalities found will likely need further evaluation to make a definitive diagnosis. Sonohysterography or diagnostic hysteroscopy can distinguish between polyps and submucous myomas, which appear similar on HSG (Fig. 29-2). A uterine septum and a bicornuate uterus cannot be differentiated on an HSG (Fig. 29-3). Evaluation of the external fundal contour by laparoscopy, magnetic resonance imaging (MRI), or threedimensional ultrasonography is required to make a definitive diagnosis. The arcuate uterus has a mild convex fundal margin and is a normal variant. Extrinsic compression from an intramural fundal myoma may give a similar appearance and is easily recognized on routine transvaginal ultrasonography. Other conditions visualized on HSG are adhesions, changes caused by diethylstilbestrol (DES), and adenomyosis. Adhesions appear as irregular filling defects and may be very mild or completely obliterate the cavity (Fig. 29-4). DES was used from the 1940s up to 1971 as prophylaxis for spontaneous abortions. The classic appearance associated with in utero DES exposure is a hypoplastic T-shaped cavity. (Fig. 29-5). Adenomyosis can occasionally be diagnosed by HSG as a cavity with shaggy borders (Fig. 29-6). The sensitivity for detecting this condition is unknown because it is uncommon in younger women and is definitely diagnosed histologically after hysterectomy.
Diagnosing Tubal Abnormalities An evidence-based study found HSG to be “a valid and accurate diagnostic test to be applied in a general population of subfertile couples to assess tubal patency but an unreliable test for diagnosing tubal occlusion.” Tubal blockage on HSG is not confirmed by laparoscopy in up to 62% of patients, but if HSG suggests patent tubes, tubal blockage is highly unlikely. Laparoscopy is needed to confirm or exclude tubal occlusion on HSG.8 It should be noted that laparoscopy is not the perfect gold standard; 2% of patients with bilateral tubal occlusion subsequently conceived
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Figure 29-1 This film demonstrates the features of a technically good study. The speculum is not obscuring anything. The tenaculum on the cervix has straightened the uterus such that it is perpendicular to the X-ray beam. The tip of the cannula remains below the internal os. The right/left marker is in place for orientation. Free spill is seen outlining loops of bowel.
Figure 29-2 A round intrauterine filling defect indicates either a polyp or a leiomyoma (black arrows). This study also shows bilateral hydrosalpinges. There is some preservation of the ampullary mucosal folds within the left tube (white arrows), and the end of the right tube is occluded (arrowheads).
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spontaneously.9 One study noted that 60% of patients with proximal tubal occlusion on HSG were patent on repeat HSG 1 month later.10 Surprisingly, hydrosalpinges may be both overdiagnosed and underdiagnosed by HSG. They may be only mildly dilated with preservation of mucosal folds or massively dilated with complete loss of the normal intratubal architecture (Fig. 29-7). HSG can also diagnose salpingitis isthmica nodosa. This condition, which predisposes to tubal occlusion and ectopic pregnancy, is similar to adenomyosis of the uterus in that there are diverticuli from the mucosa into the muscularis (Fig. 29-8). HSG is also not an ideal test for diagnosing pelvic adhesions because it detects them in only half of the cases in which they are present.2
Figure 29-3 A uterine septum cannot be differentiated from bicornuate uterus by HSG.
Figure 29-4 Extensive intrauterine adhesions associated with Asherman’s syndrome. Only some irregular areas of contrast are seen above the tip of the cannula.
Adhesions are usually diagnosed on HSG by the presence of loculated spill of contrast medium (Fig. 29-9).
INDICATIONS HSG is part of the basic infertility workup and is normally required in every patient.11 It is still the first-line technique for excluding anatomic defects in the uterine cavity and documenting tubal patency in infertility patients. A 1994 survey of boardcertified reproductive endocrinologists in the United States reported that 96% obtained an HSG as part of the basic infertility workup.12 In addition to its role in assessing the uterus and tubes, HSG may have a therapeutic effect.
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Chapter 29 Hysterosalpingography
Figure 29-5 Hypoplastic and T-shaped uterine cavity associated with in utero exposure to diethylstilbestrol.
Figure 29-7 A very large hydrosalpinx. It has no potential for repair and should be excised laparoscopically because it can reduce the pregnancy rate resulting from in vitro fertilization by half by compromising endometrial receptivity. In addition, the fluid within the tube is directly embryotoxic.
Figure 29-8 Salpingitis isthmica nodosa is diagnosed by HSG when diverticuli from the mucosa are seen extending into the muscularis in the cornual region of the uterus. The arrows point to these outpouchings. Figure 29-6 Severe adenomyosis will sometimes appear as contrast filling numerous intramural diverticuli. This condition can be confused with intravasation.
Hysterosalpingography has also been the mainstay for diagnosing uterine cavity abnormalities in women with recurrent pregnancy loss. Such abnormalities have been reported in 15% to 27% of these patients. The most common anomaly is the septate uterus; surgical correction improves the live birth rate from 3% to 20% to 70% to 90%.13 Because tubal status is not an issue with these patients, HSG may be replaced with sonohysterography. Other indications for HSG include pretubal anastomosis to determine the length of the isthmic tubal segments and exclude uterine cavity defects. It may also be used for postoperative
evaluation of the uterine cavity after hysteroscopic myomectomy, polypectomy, adhesiolysis or septoplasty or to document tubal patency after tubal anastomosis, neosalpingostomy, or ectopic pregnancy. It can aid in the delineation of known or suspected uterine anomalies, such as in DES progeny, as well as confirming proper IUD placement or tubal occlusion after ligation.
CONTRAINDICATIONS Active Pelvic Infection Pelvic inflammatory disease (PID) is an uncommon but potentially serious complication of HSG. Active cervicitis, endometritis, or salpingitis are absolute contraindications to performing an HSG. Cervical cultures for gonorrhea and chlamydia, a white blood
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Section 5 Reproductive Imaging tumor cells and worsening the prognosis for survival. Studies on using HSG for the diagnosis and follow-up of endometrial carcinoma noted that injecting contrast media under low pressure is unlikely to disseminate tumor cells and that it is doubtful that shed cells have the potential for independent metastasis.15 The 5-year survival in endometrial carcinoma patients evaluated with HSG was not significantly different in those who had positive washings after the procedure versus those who did not. Venous or lymphatic extravasation also failed to influence survival rates.16
Pregnancy
Figure 29-9 Pelvic adhesions can be diagnosed when contrast media is seen to be loculated behind peritubal adhesions after spill from a patent tube, as seen on the left. The right tube is normal with contrast spilling freely outlining loops of bowel.
cell count, and erythrocyte sedimentation rate should be obtained to rule out an active infection in patients with adnexal tenderness. They may also be considered in patients with a history of prior PID.
Severe Iodine Allergy Patients with a history of severe iodine allergy may elect to forgo HSG in favor of diagnostic laparoscopy and hysteroscopy or sonohysterosalpingography. However, the risk of a severe reaction with HSG is small because the volume of contrast (most of which escapes vaginally) is small and it is not injected intravascularly. If a decision is made to proceed with HSG in patients with known iodine allergy, a nonionic water-soluble media such as Hexabrix (ioxaglate), Isovue 370 (iopamidol), or Omnipaque (iohexol) should be used because the incidence of iodine allergy is lower with them.2 Patients with severe iodine allergy should be premedicated with prednisone 50 mg administered 13 hours before HSG and diphenhydramine 50 mg 1 hour before. In a study in 563 patients with a history of anaphylactic reactions to iodine contrast treated with this protocol, there were fewer than 10 reactions, none life threatening.14
HSG is scheduled immediately after menses to prevent performing the procedure in the presence of an unrecognized pregnancy due to the concerns of disrupting the pregnancy as well as radiation exposure. Before the advent of pregnancy testing and ultrasonography, HSG was performed specifically to diagnose pregnancy, with no untoward effects.2 HSG during inadvertent pregnancy is uncommonly reported. In a recent case report the calculated dose to the embryo was 3.7 mGy. The authors state that the teratogenic risk with less than 20 mGy during the first trimester does not justify pregnancy termination.17 The possibility of spontaneous abortion should be discussed with the patient.
TECHNICAL CONSIDERATIONS Who Should Perform the HSG? It is always preferable for the gynecologist to perform the study. Patients are comforted by having their physician present during this stressful test. Performing the procedure provides additional information not available from the static films, such as the appearance on initial filling, how rapidly the contrast traversed the tubes, how much contrast was required, and how much pressure was used. The patient can also be turned to her side to better visualize the uterus or tubes or to differentiate a true filling defect from an air bubble. The films should always be obtained for review whenever the study is performed by someone else because radiologists’ reports vary greatly depending on their training and experience. Also, the gynecologist has the advantage of being able to correlate the radiographic findings with the actual pathology at surgery. Adhering to the following protocol will reduce patient risk and discomfort and provide optimal images.
Timing Bleeding
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HSG should not be performed while the patient is menstruating because blood clots may give the false impression of an intrauterine filling defect or may occlude the uterotubal ostia. Bleeding also increases the risk for intravasation of contrast and may theoretically predispose to endometriosis by the retrograde flushing of endometrial fragments. Further, performing the procedure in a patient with unscheduled bleeding opens the possibilities that she may have a pregnancy complication or endometrial carcinoma.
The procedure should be performed during the window between the end of menses and before ovulation. This will reduce the risk of flushing an embryo out of the uterus or tube, disrupting an implanted embryo, or exposing it to radiation. The endometrium is thin during the early follicular phase, which reduces false positives for filling defects or proximal tubal occlusion due to thick mucosal folds. Waiting for the completion of menses reduces the risk of intravasation, filling defects from clots, and the theoretical risk of inducing endometriosis by retrograde flushing of endometrial fragments through the tubes.
Endometrial Carcinoma
Analgesia
It is felt to be prudent to avoid performing HSG in known or suspected cases of endometrial carcinoma for fear of disseminating
Unfortunately, most patients experience uterine cramping during the HSG, but the entire procedure usually only lasts
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Chapter 29 Hysterosalpingography about 3 minutes and the discomfort resolves rapidly at the end of the procedure. A prospective, double-blind, randomized, controlled trial comparing 1 g of acetominophen to placebo taken 30 minutes before HSG found no significant difference in mean pain scores during or 24 hours after the procedure.18 Several studies noted that nonsteroidal anti-inflammatory drugs (NSAIDs) did provide significant analgesia for HSG.19–21 Two randomized, placebo-controlled studies found no difference with intrauterine anesthetics delivered before the HSG. Patients in both studies also received an NSAID, which may have decreased pain enough to mask any beneficial effect of the anesthetic.22,23 There are no references on the use of paracervical blockade for HSG.
Oil-soluble versus Water-soluble Contrast Media The water-soluble media and oil-soluble media camps have been arguing the relative merits of their favored contrast for decades; as yet there is no clear winner. Water-soluble media offers better image quality because the higher density oil-soluble media tends to obscure fine details in the uterus and tubal mucosal folds. Also, because water-soluble media dissipates quickly, there is no need for delayed films, whereas 1- to 24-hour delayed films are necessary with oil-soluble media. Oil-soluble media also carries increased risks for oil embolism and granuloma formation. Proponents of oil-soluble media counter that water-soluble media causes increased pain on peritoneal spill, although it is mild and very transient. Water-soluble media with lower osmolality may cause less irritation and discomfort.2 The procedure should be performed with the smallest volume of contrast possible to provide the needed information. The biggest argument in favor of oil-soluble media is that it has higher postprocedure pregnancy rates. Most still advocate water-soluble media because it provides better uterine and ampullary mucosal detail and has no serious secondary effects.3,6
Types of Cannulas Rigid metal cannulas have been the standard device for performing HSG because they are inexpensive, reusable, and readily available. A balloon catheter can be employed in rare cases when cervical stenosis or an inadequate cervical seal prevent completion of the study with the rigid cannula. In addition to the cost of the disposable balloon catheter, it is more difficult to manipulate the uterus compared to a rigid cannula with a tenaculum. Also, the balloon obscures the lower uterine segment. One study reported that the balloon catheter caused significantly greater pain after the procedure.24 However, a randomized study found that HSG performed with a balloon catheter required less contrast and fluoroscopy time, produced less patient discomfort, and was easier for senior residents to perform. It has the additional advantage of allowing the clinician to perform immediate selective salpingography and transcervical tubal catheterization for proximal tubal occlusion without the need to replace the cannula or reschedule the patient.25 A randomized study comparing the rigid cannula to a cervical vacuum cup cannula reported that HSG performed with the disposable vacuum device was quicker to perform, required less contrast and fluoroscopy time, caused less patient discomfort, and was easier for senior residents to perform.26
Technique The cannula is attached to a 20-cc syringe filled with contrast media, then flushed to expel all the air to prevent air bubble artifacts. The acorn is adjusted so that it is about 1 cm from the end of the cannula. The cannula tip should not go beyond the internal os. After informed consent is obtained, the patient is placed in lithotomy position, with towels or sheets under the buttocks for elevation. Using a lubricated open-sided bivalve speculum, the cervix is prepared with an antiseptic solution; then a single-toothed tenaculum is gently applied to the anterior lip of the cervix. The cannula tip is inserted through the external os and the speculum is removed. Applying gentle upward pressure on the cannula while pulling downward on the tenaculum will seal the cervix and straighten the uterine axis. Occasionally, it is easier to push upward on the tenaculum to invert the uterus to get it perpendicular to the X-ray beam. A right or left marker should be placed on the film cassette for orientation. Fluoroscopy is initiated with the cannula tip aligned at the lower end of the frame and the pelvis observed for any abnormalities that may affect the interpretation of the study. In the absence of any obvious abnormalities, a scout film only increases radiation exposure without providing additional significant information.27 Contrast media is then injected slowly both for patient comfort as well as to delineate any subtle uterine filling defects that may not be visible after complete filling, particularly with the denser oil-soluble contrast media. A film may be taken during initial filling. If a filling defect is suspected to be an air bubble, the patient can be rotated on her side (defect side down). A polyp or myoma will remain stationary, whereas a bubble will rise to the elevated side. The injection of contrast continues while watching the fallopian tubes opacify and spill. Only 5 to 10 mL are usually required to complete the study. Water-soluble contrast media will be seen to outline loops of bowel immediately, but a delayed film is needed to confirm free spill of oil-soluble media. Oneand 24-hour delayed films were equivalent for determining tubal status, but the 1-hour interval was less accurate for diagnosing peritubal adhesions.28 Patients should be observed for a few minutes for bleeding and signs of vasovagal or allergic reactions.
SPECIAL CASES Cervical Stenosis or Leaking A uterine sound or small dilator is usually adequate to complete the procedure when cervical stenosis initially prevents inserting the cannula. A paracervical block may be administered to reduce discomfort in particularly difficult cases. As mentioned, the smaller diameter balloon catheter may be more easily passed through a stenotic external os. A pediatric feeding tube or intrauterine insemination catheter may also be used in these instances. A larger acorn tip may be placed on the cannula in cases of leaking contrast due to an inadequate seal from a patulous cervix. Alternatively, a balloon catheter may be used to occlude the cervix or a second tenaculum may be applied to the posterior lip of the cervix to diminish the diameter of the external os.
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Section 5 Reproductive Imaging Proximal Tubal Occlusion Although bilateral proximal tubal occlusion is usually indicative of anatomic pathology, unilateral proximal tubal occlusion is frequently transient due to spasm of the uterotubal ostium or to plugging by mucus, debris, or air bubbles. Unilateral proximal tubal occlusion is found in 10% to 24% of patients, but 16% to 80% are patent on repeat HSG or laparoscopy with chromotubation.29 Increasing the hydrostatic pressure will establish patency in a high percentage of patients, 72% in one large series.10 In one study, rotating the patient such that the proximal tubal occlusion faces down establishes patency in 63%. The authors suggested that this effect was due to unkinking the tube, but dislodging an air bubble is also possible. Rotating the patient so the proximal tubal occlusion side faces up never resulted in patency.29 The use of antispasmodic agents such as glucagon to prevent proximal tubal occlusion due to spasm has also been recommended, but the literature contains only anecdotal reports.
Management of Proximal Tubal Occlusion As noted, 60% of patients with proximal tubal occlusion on HSG were shown to be patent on repeat HSG 1 month later.10 Therefore, we do not attempt to correct the problem at the initial HSG. Selective salpingography may be attempted if a repeat HSG at least 1 month later confirms persistent proximal tubal occlusion. The repeat HSG is performed with a balloon catheter under intravenous conscious sedation and a #5 French catheter advanced through it and wedged in the cornua under fluoroscopic guidance. Contrast media is then injected, establishing patency in one third of the tubes.3 Tubal cannulation may be attempted in the two thirds of the tube that remained occluded during selective salpingography. A flexible guidewire is then passed through the tubal ostium and, if successful, a #3 French catheter is advanced over the wire and contrast media is injected (Fig. 29-10). The procedure is successful more than 85% of the time.2 Excision of the proximal tubes in cases of failed tubal cannulation revealed salpingitis isthmica nodosa, chronic salpingitis, or fibrosis in 93%.30 The conception rate within 6 to 12 cycles is 30% to 40% with a 5% to 10% ectopic rate.2 Approximately one third of the opened tubes reocclude.2,3 The radiation dose ranged from 25 cGy for unilateral or bilateral selective salpingography to 78.5 gGy for bilateral tubal cannulation.31 Tubal perforation has been reported in 3% to 11% but was always innocuous.32 If laparoscopy is indicated, tubal cannulation can be performed by directing the guidewire and inner catheter into the tubal ostium through the operating cannel of a hysteroscope. Success rates in terms of patency, pregnancy, reocclusion, and perforation are nearly identical.
RISKS Vasovagal Reactions
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Less than 5% of patients may experience some of the features of a vasovagal reaction, with light-headedness, pallor, sweating, bradycardia, and hypotension.15 It usually resolves spontaneously within a few minutes. Patients are kept supine on the table with their legs elevated until all symptoms have subsided. Atropine
Figure 29-10 Selective salpingography and tubal cannulation. The curved #5 French outer plastic catheter has been lodged in the right cornua (arrow) under fluoroscopic guidance and selective salpingography has been attemped unsuccessfully. Tubal cannulation was then performed by gently placing a #3 French inner catheter with a flexible guidewire through the uterotubal ostium into the proximal isthmus (arrow) under fluoroscopic guidance. The guidewire was removed and contrast injected through the #3 French catheter to confirm patency of the distal tube.
0.4 mg may be administered subcutaneously in the very rare more profound and protracted cases.
Infection A 1983 study reported that 1.4% of patients undergoing HSG developed PID and all had tubal dilation. The overall frequency of PID in women with dilated tubes was 11%.33 In this study, patients with a history of PID or a positive chlamydia titer were administered doxycycline 100 b.i.d. for 5 days beginning 2 days before the HSG. If dilated tubes were unexpectedly noted on HSG, the same 5-day regimen of doxycycline was initiated right after the HSG. No cases of PID were observed in women who received antibiotic treatment. The current American College of Obstetricians and Gynecologists recommendation is that no prophylactic antibiotics be given in the absence of a history of PID unless hydrosalpinges are noted.34 It may be safer and more cost-effective to proceed directly to laparoscopy in patients with a history of PID, prior treatment for gonorrhea or chlamydia, or a positive chlamydia antibody titer. Not only will this eliminate the risk of post-HSG infection, but these patients are also significantly more likely to have pelvic pathology requiring surgical correction.
Radiation The radiation dose depends on the patient’s size, position of the ovaries, the machine used, the distance between the ovaries and the machine, the duration of fluoroscopy, the number of images taken, and the degree of image magnification.2 Every effort should be made to reduce the fluoroscopy time and limit the number of images taken. Generally, no more than two spot films are necessary, and the typical study requires less than 10 seconds of fluoroscopy time.35 The average ovarian dose is 2.8 to 4.6 mGy.36 Nearly 75% of the total dose was attributable to capturing film images and the
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Chapter 29 Hysterosalpingography remainder to fluoroscopy.37 Using a digital system reduced the dosage sixfold compared with analog systems.36 The patienteffective dose from an average HSG is less than half of the annual background radiation dose in the United States. The risk38 for an anomaly in a future embryo was estimated to be 27 × 10−6 and the risk for a fatal cancer in patients at highest risk (under 30 years old) was 145 × 10−6.
Granuloma Formation Water-soluble media is absorbed within minutes, whereas oilsoluble contrast media can persist for months or even years in cases of obstructed tubes, which can be problematic during future abdominal radiographic studies. Persistence of the contrast has the potential to induce a foreign body reaction (granuloma) in the uterus or tubes. There are no data on the prevalence of granulomas or whether they are detrimental to fertility.2 Watersoluble media should certainly be selected in patients at risk for distal obstruction, but granulomas seldom occur when the tubes are normal.3
Oil Embolism Intravasation, the entrance of contrast medium into the myometrial veins and lymphatics, occurs in up to 7% of patients (Fig. 29-11).39 Risk factors for intravasation include tubal obstruction, recent uterine surgery, uterine malformations, misplaced cannula, and excessive injection pressure or quantity of media.2 The intravasated contrast quickly passes through the uterine and ovarian veins to the lungs. Water-soluble media is rapidly dissipated and has an extremely low potential to cause embolic symptoms or side effects, whereas nearly all of the
reported embolic complications, including deaths, resulted from use of oil-soluble media. Approximately 20% of patients with oil-soluble media intravasation develop symptoms, including chest pain, cough, dyspnea, light-headedness, confusion, headache and, rarely, cardiorespiratory failure and death. Patients may also have hematuria, hemoptysis, hemolysis, fever, leukocytosis, pneumonia, lipuria, and medium in peripheral vessels, especially the brain. This has rarely been a problem in recent years due to the universal use of fluoroscopy, which allows for the immediate recognition of intravastion and termination of the procedure.2 In fact, there have been no deaths from oil-soluble media embolism since 1947, when fluoroscopy replaced spot films.3
FERTILITY ENHANCEMENT A major purported advantage of HSG is an increased postprocedure pregnancy rate. Two meta-analyses confirmed that pregnancy rates were significantly higher in patients who received oil-soluble media.40,41 There are numerous possible mechanisms by which this occurs: the more viscous oil-soluble media may result in higher hydrostatic pressures to dislodge intraluminal plugs and break down adhesions. It may also have a bacteriostatic effect, stimulate ciliary action, inhibit sperm phagocytosis by peritoneal mast cells, and emulsify tubal debris.3 However, even with water-soluble media, 29% conceived after HSG, with a fourfold higher pregnancy rate during the first 3 months after the test.42 A recent large multicenter trial, which randomized patients to water-soluble media, oil-soluble media, or oil-soluble media following water-soluble media, found no differences in live birth rates.43 This study was included in the current Cochrane analysis, which came to the following conclusions: HSG with oil-soluble media significantly increased the pregnancy rate by an odds ratio (OR) of 3.57 versus no intervention. There were no randomized trials to assess water-soluble media versus no intervention. There were no significant differences between the pregnancy rates with oil-soluble media and water-soluble media.41 As early as 1980, it was suggested that the tubes should be flushed with oil-soluble media after confirming patency with water-soluble media to reduce the complications associated with oil-soluble media while retaining its presumed higher therapeutic effect.44 Subsequent randomized studies found no advantage to this practice.3,41,45
ALTERNATIVE PROCEDURES Chlamydia Antibody Testing
Figure 29-11 Intravasated contrast fills the myometrial veins and lymphatics and extends up the pelvic veins.
Half of PID cases are due to Chlamydia trachomatis, and 50% to 80% of those are asymptomatic. There was a marked association between the chlamydia antibody titer and the likelihood of tubal damage.46 A meta-analysis showed that chlamydia antibody testing by enzyme-linked immunosorbent assay or immunofluorescense is comparable to HSG in the diagnosis of tubal patency but provides no details on the anatomy of the uterus or tubes.47 Although chlamydia antibody testing is not going to replace HSG as the first-line screening test to evaluate the uterine cavity and tubes, it may have a role in helping to decide which patients with a normal HSG should undergo a diagnostic laparoscopy
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Section 5 Reproductive Imaging because patients with positive titers may have adnexal adhesions and subtle tubal disease not detected by HSG.
Sonohysterography (SHG) is a quick, painless office procedure accomplished by injecting saline solution into the uterine cavity through an intrauterine insemination catheter while performing transvaginal ultrasonography. SHG, HSG, and hysteroscopy are equivalent for the evaluation of the uterine cavity. In addition, SHG provides information on the myometrium and the ovaries, avoids the discomfort and radiation of HSG, and is less expensive than hysteroscopy.48 SHG should be used instead of HSG when evaluation of the tubes is not necessary, such as in cases of recurrent pregnancy loss or infertility where tubal status had been previously documented by laparoscopy.48,49 Sonohysterosalpingography, also called hysterosalpingocontrast sonography (HyCoSy), utilizes a transcervical balloon catheter to inject either saline solution with air bubbles, sonicated albumin, or Echovist-200, a galactose solution with microbubbles, under transvaginal ultrasound guidance to document tubal patency. Similar to SHG, it has the advantages of being performed in the office, avoiding radiation exposure, and visualizing the myometrium and ovaries. A randomized study comparing HyCoSy and HSG to laparoscopy with chromotubation reported that both imaging techniques were comparable in terms of diagnostic accuracy, patient pain, and preference. The authors concluded that there appeared to be no strong arguments either to replace HSG by HyCoSy or to reject the use of HyCoSy.50 Of concern, another study noted that of women diagnosed with tubal occlusion by HyCoSy, 47% were shown to be patent on subsequent HSG. Severe pain or vasovagal symptoms occurred in 21% of patients undergoing HyCoSy versus none with HSG. Finally, HyCoSy with Echovist-200 costs 10 times more than HSG.51 A recent HyCoSy study also reported that HSG had a higher sensitivity than HyCoSy for tubal occlusion and 59% of the patients experienced moderate to severe pain with HyCoSy. The authors note that HyCoSy does not image the entire tube and that HSG gives a more accurate location of tubal obstruction.52 HyCoSy cannot yet replace HSG.11
Bypassing HSG in favor of diagnostic laparoscopy and hysteroscopy to assess the uterus and tubes is probably more costeffective in patients with pelvic pain, adnexal masses, or other indications for surgery, as well as a history of PID or prior pelvic surgery. These patients are much more likely to have pelvic pathology requiring surgical treatment. It is debatable when and if laparoscopy should be recommended when the HSG is normal. Of 265 infertility patients with a normal HSG, only 7% were felt to have clinically significant disease.55 Pain symptoms or positive chlamydia antibody titers could help to better select patients for laparoscopy. Hysteroscopy is not justified if the HSG is normal because HSG has a high sensitivity for uterine cavity abnormalities, and false negatives are of doubtful clinical significance.7,56,57 Transvaginal hydrolaparoscopy (TVHL) is a relatively new procedure that can be performed in the office without anesthesia. It involves placing a small rigid scope through a colpotomy incision and floating the bowel out of the pelvis with warm saline solution. It can be combined with hysteroscopy to assess the uterus as well as with chromotubation and salpingoscopy. A study of 23 patients who underwent both TVHL with office hysteroscopy and HSG reported that the former had lower pain scores but that the test took more than twice as long to complete.58 Transvaginal hydrolaparoscopy followed by laparoscopy was performed in patients with unexplained infertility. Findings were concordant in 80%, and discordant findings were not considered to have clinical consequence. The authors concluded that laparoscopy could have been avoided in 93%.59 TVHL combined with office hysteroscopy has the potential to replace HSG as the initial screening test for infertility patients. In addition to evaluating the endometrial cavity and tubal patency, it affords a view of the pelvic cavity, even if not as accurate or complete as laparoscopy. The addition of salpingography may yield further information regarding the ampullary lumen. TVHL and hysteroscopy may also be better tolerated than HSG. More studies are needed before HSG can be displaced as the mainstay study for infertility.
MRI and Three-dimensional Ultrasonography
Salpingoscopy and Falloposcopy
HSG using gadolinium contrast and MRI was proposed with the advantages of avoiding radiation and the ability to visualize the myometrium and ovaries. However, a pilot study noted that the tubes were very poorly visualized.53 MRI and three-dimensional ultrasonography should be limited to distinguishing between septate and bicornuate uteri noted on HSG.
Salpingoscopy is performed by introducing a small scope through the fimbria up to the ampullary–isthmic junction at laparoscopy. The tube is examined by injecting saline solution while withdrawing the scope. The primary indication for salpingoscopy is as a prognostic factor for pregnancy after neosapingostomy for hydrosalpinges. Patients with a normal salpingoscopy had significantly higher pregnancy and lower ectopic pregnancy rates than patients with abnormal salpingoscopic findings. Salpingoscopy was superior to HSG for predicting pregnancy.60 Studies comparing HSG and salpingoscopy noted that HSG had a 45% false-negative and a 30% false-positive rate for diagnosing tubal disease.60,61 Interest in salpingoscopy has been renewed because it can be performed during TVHL.62 However, only 26.4% to 64% of the tubes could be visualized by salpingoscopy during TVHL.63,64 Falloposcopy, unlike salpingoscopy, examines the entire tube in antegrade fashion with a 0.5-mm diameter scope in a 0.8-mm Teflon sheath. The scope is guided into the uterotubal ostium
Sonohysterography and Sonohysterosalpingography
Radionuclide Scanning
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Diagnostic Laparoscopy and Hysteroscopy
Radionuclide HSG has been evaluated as a more functional approach to tubal infertility diagnosis than conventional patency tests. Technetium-99m labeled human serum albumin microsphere particles were placed in the cervical canal and images taken for up to 5 hours. Radionuclide HSG investigation is not able to predict fertility potential because the same percentage of women conceived, with and without demonstrated patency.54 Additionally, it provides no information on the anatomy of the uterus or tubes.
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Chapter 29 Hysterosalpingography through the operating channel of a hysteroscope or with a linear everting catheter.65,66 Fluid is injected through the sheath to displace the endosalpinx off the lens and improve visualization. A classification of normal and abnormal falloscopic findings was reported in 1992 and showed that it had some prognostic value. The tubes could be cannulated 85% to 95% of the time in large series, but the distal tube becomes too wide beyond the ampullary–isthmic junction for the entire width of the lumen to be visualized.11 No images were of sufficient quality to describe the entire tubal mucosa in detail. Technical problems such as “white out” and catheter kinking also limit the usefulness of this method in routine clinical practice.67 Tubal perforation rates up to 10% have been reported, all with severe fibrotic proximal tubal occlusion and without adverse sequelae.68 The technique never gained acceptance.
SUMMARY HSG is quick, easy to perform, and subjects the patient to only transient discomfort and minimal radiation exposure. It may also increase the pregnancy rates in the following months. Water-soluble media yields better images and avoids the need for a delayed film and the risks of retained contrast, granuloma formation, and embolism. HSG has a high sensitivity but low specificity for defects within the endometrial cavity. Polyps and myomas can easily be differentiated with SHG, and septate and bicornuate uteri can be distinguished with MRI, three-dimensional ultrasonography, or laparoscopy.
Hysterosalpingography is very accurate for confirming tubal patency but not for occlusion. Persistent proximal tubal occlusion can be treated with selective salpingography or tubal cannulation with a high degree of success. Although other techniques to evaluate the uterine cavity and tubal patency have some advantages over HSG, HSG remains the first-line test for the workup of the infertile woman.
PEARLS ●
●
●
●
●
●
●
HSG is the best diagnostic test for the evaluation of the fallopian tubes. HSG is performed after a menstrual period and before ovulation. Patients with irregular periods should have a pregnancy test performed. Hydrosalpinx increases the risk of procedure-related infection. Antibiotics should be given to the patient after the procedure. Repeat HSG should be performed after the diagnosis of bilateral proximal tubal occlusion before proceeding to treatment. Salpingitis isthmica nodosa is characterized by diverticula in the proximal uterine tube and is associated with infertility and ectopic pregnancy. The risk for an anomaly in a future embryo exposed to the test radiation is no greater than that of an unexposed patient.
REFERENCES 1. Karande VC, Pratt DE, Rabin DS, Gleicher N: The limited value of hysterosalpingography in assessing tubal status and fertility potential. Fertil Steril 63:1167–1171, 1995. 2. Soules MR, Mack LA: Imaging of the reproductive tract in infertile women: Hysterosalpingography, ultrasonography and magnetic resonance imaging. In Keye WR, Chang RJ, Rebar RW, Soules MR (eds). Infertility Evaluation and Treatment. Philadelphia, W.B. Saunders, 1995, pp 300–329. 3. Pinto AB, Hovsepian DM, Wattanakumtornkul S, Pilgram TK: Pregnancy outcomes after fallopian tube recanalization: Oil-based versus watersoluble contrast agents. J Vasc Intervent Radiol 14:69–74, 2003. 4. Glatstein IZ, Sleeper LA, Lavy Y, et al: Observer variability in the diagnosis and management of the hysterosalpingogram. Fertil Steril 67:233–237, 1997. 5. Renbaum L, Ufberg D, Sammel M, et al: Reliability of clinicians versus radiologists for detecting abnormalities on hysterosalpingogram films. Fertil Steril 78:614–618, 2002. 6. Ubeda B, Paraira M, Alert E, Abuin RA: Hysterosalpingography: Spectrum of normal variants and nonpathologic findings. Am J Roentgenol 177:131–135, 2001. 7. Preutthipan S, Linasmita V: A prospective comparative study between hysterosalpingography and hysteroscopy in the detection of intrauterine pathology in patients with infertility. J Obstet Gynaecol Res 29:33–37, 2003. 8. Evers JL, Land JA, Mol BW: Evidence-based medicine for diagnostic questions. Semin Reprod Med 21:9–15, 2003. 9. Mol BW, Collins JA, Burrows EA, et al: Comparison of hysterosalpingography and laparoscopy in predicting fertility outcome. Hum Reprod 14:1237–1242, 1999. 10. Dessole S, Meloni GB, Capobianco G, et al: A second hysterosalpingography reduces the use of selective technique for treatment of a proximal tubal obstruction. Fertil Steril 73:1037–1039, 2000.
11. Hedon B, Dechaud H, Boulot P, Laffargue F: Critical evaluation of the fallopian tube. In Kempers RD, Cohen J, Haney AF, Younger BJ (eds). Fertility and Reproductive Medicine. Amsterdam, Elsevier Science, 1998, pp 61–70. 12. Glatstein IZ, Harlow BL, Hornstein MD: Practice patterns among reproductive endocrinologists: Further aspects of the infertility evaluation. Fertil Steril 70:263–269, 1997. 13. Alborzi S, Dehbashi S, Parsanezhad ME: Differential diagnosis of septate and bicornuate uterus by sonohysterography eliminates the need for laparoscopy. Fertil Steril 78:176–178, 2002. 14. Greenberger PA, Patterson R, Radin RC: Two pretreatment regimens for high-risk patient receiving radiographic contrast media. JAMA 241:2813–2815, 1979. 15. Hunt RB, Siegler AM: Hysterosalpingography: Techniques & Interpretation. Chicago, Year Book Medical Publishers, 1990. 16. DeVore GR, Schwartz P, Morris J: Hysterography: A 5–year follow-up in patients with endometrial carcinoma. Obstet Gynecol 60:369, 1982. 17. Jongen VH, Collins JM, Lubbers JA, van Selm M: Unsuspected early pregnancy at hysterosalpingography. Fertil Steril 76:610–611, 2001. 18. Elson EM, Ridley NT: Paracetamol as a prophylactic analgesic for hysterosalpingography: A double blind randomized controlled trial. Clinical Radiology 55:675–678, 2000. 19. Owens OM, Schiff I, Kaul AF, et al: Reduction of pain following hysterosalpingogram by prior analgesic administration. Fertil Steril 43:146–148, 1985. 20. Lorino CO, Prough SG, Aksel S, et al: Pain relief in hysterosalpingography. A comparison of analgesics. J Reprod Med 35:533–536, 1990. 21. Peters AA, Witte EH, Damen AC, et al: Pain relief during and following outpatient curettage and hysterosalpingography: A double blind study to compare the efficacy and safety of tramadol versus naproxen. Cobra Research Group. Eur J Obstet Gynecol Reprod Biol 66:51–56, 1996.
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22. Costello MF, Horrowitz S, Steigrad S, et al: Transcervical intrauterine topical local anesthetic at hysterosalpingography: A prospective, randomized, double-blind, placebo-controlled trial. Fertil Steril 78:1116–1122, 2002. 23. Frishman GN, Spencer PK, Weitzen S, et al: The use of intrauterine lidocaine to minimize pain during hysterosalpingography: A randomized trial. Obstet Gynecol 103:1261–1266, 2004. 24. Varpula M: Hysterosalpingography with a balloon catheter versus a cannula: Evaluation of patient pain. Radiology 172:745–747, 1989. 25. Tur-Kaspa I, Seidman DS, Soriano D, et al: Hysterosalpingography with a balloon catheter versus a metal cannula: A prospective, randomized, blinded comparative study. Hum Reprod 13:75–77, 1998. 26. Cohen SB, Wattiez A, Seidman DS, et al: Comparison of cervical vacuum cup cannula with metal cannula for hysterosalpingography. BJOG 108:1031–1035, 2001. 27. Okpala OC, Adinma JI, Ikechebelu JI: Assessment of the value of preliminary films at hysterosalpingography. West African J Med 19:105–106, 2000. 28. Reshef E, Daniel WW, Foster JC, et al: Comparison between 1-hour and 24-hour follow-up radiographs in hysterosalpingography using oil based contrast media. Fertil Steril 52:753–755, 1989. 29. Hurd WW, Wyckoff ET, Reynolds DB, et al: Patient rotation and resolution of unilateral cornual obstruction during hysterosalpingography. Obstet Gynecol 101:1275–1278, 2003. 30. Letterie GS, Sakas EL: Histology of proximal tubal obstruction in cases of unsuccessful tubal canalization. Fertil Steril 56:831, 1991 31. Papaioannou S, Afnan M, Coomarasamy A, et al: Long term safety of fluoroscopically guided selective salpingography and tubal catheterization. Hum Reprod 17:370–372, 2002. 32. Dessole S, Farina M, Rubattu G, et al: Side effects and complications of sonohysterosalpingography. Fertil Steril 80:620–624, 2003. 33. Pittaway DE, Winfield AC, Maxson W, et al: Prevention of acute pelvic inflammatory disease after hysterosalpingography: Efficacy of doxycycline prophylaxis. Am J Obstet Gynecol 147:623–626, 1983. 34. American College of Obstetricians and Gynecologists: Antibiotic Prophylaxis for Gynecologic Procedures. ACOG Practice Bulletin, Number 23, 2001. 35. Richmond JA: Hysterosalpingography. In Lobo RA, Mishell DR, Paulson RJ, Shoup D (eds). Mishell’s Textbook of Infertility, Contraception, and Reproductive Endocrinology, 4th ed. Boston, Blackwell Science, 1997, pp 567–579. 36. Gregan AC, Peach D, McHugo JM: Patient dosimetry in hysterosalpingography: A comparative study. Brit J Radiol 71:1058–1061, 1998. 37. Fernandez JM, Vano E, Guibelalde E: Patient doses in hysterosalpingography. Brit J Radiol 69:751–754, 1996. 38. Perisinakis K, Damilakis J, Grammatikakis J, et al: Radiogenic risks from hysterosalpingography. Eur Radiol 13:1522–1528, 2003. 39. Nunley WCJ, Bateman BG, Kitchin JD, Pope TLJ: Intravasation during hysterosalpingography using oil-base contrast medium—a second look. Obstet Gynecol 70:309–312, 1987. 40. Watson A, Vandekerckhove P, Lilford R, et al: A meta-analysis of the therapeutic role of oil soluble contrast media at hysterosalpingography: A surprising result? Fertil Steril 61:470–477, 1994. 41. Johnson N, Vandekerckhove P, Watson A, et al: Tubal flushing for subfertility. Cochrane Database Sys Rev 2005:2:CD003718. 42. Cundiff G, Carr BR, Marshburn PB: Infertile couples with a normal hysterosalpingogram. Reproductive outcome and its relationship to clinical and laparoscopic findings. J Reprod Med 40:19–24, 1995. 43. Spring DB, Barkan HE, Pruyn SC: Potential therapeutic effects of contrast materials in hysterosalpingography: A prospective randomized clinical trial. Kaiser Permanente Infertility Work Group. Radiology 214:53–57, 2000. 44. DeCherney AH, Kort H, Barney JB, DeVore GR: Increased pregnancy rate with oil-soluble hysterosalpingography dye. Fertil Steril 33:407–410, 1980. 45. Steiner AZ, Meyer WR, Clark RL, Hartmann KE: Oil-soluble contrast during hysterosalpingography in women with proven tubal patency. Obstet Gynecol 101:109–113, 2003.
46. Thomas K, Coughlin L, Mannion PT, Haddad NG: The value of Chlamydia trachomatis antibody testing as part of routine infertility investigations. Hum Reprod 15:1079–1082, 2000. 47. Mol BW, Dijkman B, Wertheim P, et al: The accuracy of serum chlamydial antibodies in the diagnosis of tubal pathology: A meta-analysis. Fertil Steril 67:1031–1037, 1997. 48. Goldberg JM, Falcone T, Attaran M: Sonohysterographic evaluation of uterine abnormalities noted on hysterosalpingography. Hum Reprod 12:2151–2153, 1997. 49. Brown SE, Coddington CC, Schnorr J, et al: Evaluation of outpatient hysteroscopy, saline infusion hysterosonography, and hysterosalpingography in infertile women: A prospective, randomized study. Fertil Steril 74:1029–1034, 2000. 50. Dijkman AB, Mol BW, Van der Veen F, et al: Can hysterosalpingocontrastsonography replace hysterosalpingography in the assessment of tubal subfertility? Eur J Radiol 35:44–48, 2000. 51. Stacey C, Bown C, Manhire A, Rose D: HyCoSy—as good as claimed? Brit J Radiol 73:133–136, 2000. 52. Exacoustos C, Zupi E, Carusotti C, et al: Hysterosalpingo-contrast sonography compared with hysterosalpingography and laparoscopic dye pertubation to evaluate tubal patency. J Am Assoc Gynecol Laparosc 10:367–372, 2003. 53. Unterweger M, De Geyter C, Frohlich JM, et al: Three-dimensional dynamic MR-hysterosalpingography: A new, low invasive, radiation-free and less painful radiological approach to female infertility. Hum Reprod 17:3138–3141, 2002. 54. Lundberg S, Wramsby H, Bremmer S, et al: Radionuclide hysterosalpingography is not predictive in the diagnosis of infertility. Fertil Steril 69:216–220,1998. 55. al-Badawi IA, Fluker MR, Bebbington MW: Diagnostic laparoscopy in infertile women with normal hysterosalpingograms. J Reprod Med 44:953–957, 1999. 56. Cohen LS, Valle RF: Role of vaginal sonography and hysterosonography in the endoscopic treatment of uterine myomas. Fertil Steril 73:197–204, 2000. 57. Hourvitz A, Ledee N, Gervaise A, et al: Should diagnostic hysteroscopy be a routine procedure during diagnostic laparoscopy in women with normal hysterosalpingography? Reprod Biomed Online 4:256–260, 2002. 58. Cicinelli E, Matteo M, Causio F, et al: Tolerability of the minipanendoscopic approach (transvaginal hydrolaparoscopy and minihysteroscopy) versus hysterosalpingography in an outpatient infertility investigation. Fertil Steril 76:1048–1051, 2001. 59. Watrelot A, Nisolle M, Chelli H, et al: Is laparoscopy still the gold standard in infertility assessment? A comparison of fertiloscopy versus laparoscopy in infertility. Results of an international multicentre prospective trial: The FLY (Fertiloscopy-LaparoscopY) study. Hum Reprod 18:834–839, 2003. 60. Henry-Suchet J, Tesquiter L, Pez JP, Loffredo V: Prognostic value of tuboscopy vs. hysterosalpingography before tuboplasty. J Reprod Med 29:609–612, 1984. 61. Puttemans P, Brosens I, Delattin P, et al: Salpingoscopy versus hysterosalpingography in hydrosalpinges. Hum Reprod 2:535–540, 1987. 62. Watrelot A, Dreyfus JM, Cohen M: Systematic salpingoscopy and microsalpingoscopy during fertiloscopy. J Am Assoc Gynecol Laparosc 9:453–459, 2002. 63. Gordts S, Campo R, Rombauts L, Brosens I: Transvaginal salpingoscopy: An office procedure for infertility investigation. Fertil Steril 70:523–526, 1998. 64. Fujiwara H, Shibahara H, Hirano Y, et al: Usefulness and prognostic value of transvaginal hydrolaparoscopy in infertile women. Fertil Steril 79:186–189, 2003. 65. Kerin JF, Pearlstone AC, Surrey ES: Tubal microendoscopy: Salpingoscopy and falloposcopy. In Keye WR, Chang RJ, Rebar RW, Soules MR (eds). Infertility Evaluation and Treatment. Philadelphia, W.B. Saunders, 1995, pp 372–386. 66. Pearlstone AC, Surrey ES, Kerin JF: The linear everting catheter: A nonhysteroscopic, transvaginal technique for access and microendoscopy of the fallopian tube. Fertil Steril 58:854–857, 1992.
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Chapter 29 Hysterosalpingography 67. Lundberg S, Rasmussen C, Berg AA, Lindblom B: Falloposcopy in conjunction with laparoscopy: Possibilities and limitations. Hum Reprod 13:1490–1492, 1998. 68. Kerin JF, Pearlstone AC, Surrey ES: Cannulation of the fallopian tube and falloposcopy: Difficulties and complications. In Corfman RS, Diamond MP, DeCherney A (eds). Complications of Laparoscopy and Hysteroscopy. Oxford, Blackwell Scientific, 1993, pp 223–235.
69. Goldberg J, Falcone T: Effect of DES on reproductive function. Fertil Steril 72:1–7, 1999. 70. Goldberg JM, Falcone T: Congenital malformations of the female genital tract: Diagnosis and management. In: Gidwani G, Falcone T (eds). Müllerian Anomalies: Reproduction, Diagnosis, and Treatment. Philadelphia, Lippincott Williams & Wilkins, 1999, pp 177–204.
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Section 5 Reproductive Imaging Chapter
30
Pelvic Ultrasonography and Sonohysterography Steven R. Lindheim and Meike L. Uhler
INTRODUCTION Ultrasonography is an invaluable diagnostic tool for the assessment of uterine and pelvic pathology.1 The use of both transabdominal and transvaginal ultrasonography has become widespread because it is a safe, noninvasive, and readily available tool in the office setting. For evaluation of uterine cavity abnormalities, the diagnostic accuracy of ultrasonography is improved considerably by injecting normal saline solution into the uterine cavity during a procedure referred to as sonohysterography. For many conditions and complaints, ultrasonography has become one of the standard first steps in the diagnostic evaluation. Surgery remains the gold standard for evaluation of the internal and external surfaces of pelvic organs, often by laparoscopy or hysteroscopy. Although these diagnostic modalities are both sensitive and specific, they are most often performed in an operating room setting under regional or general anesthesia and pose significantly greater risks and costs than ultrasonography. In addition, they cannot evaluate structures within the uterine wall and ovaries without damaging these structures. Ultrasonography and sonohysterography are two of the most important technologic advancements introduced into the practice of obstetrics and gynecology because they can improve noninvasive clinical assessment of both the surface and internal structure of the pelvic organs, and thus optimize treatment decisions. This chapter focuses on the basic physical principles of gynecologic ultrasonography; the indications, techniques, and applications of ultrasonography and sonohysterography; and normal and abnormal pelvic findings associated with these techniques. A review of the utility of these diagnostic studies for different pathologic conditions as well as their comparative value to each other and existing gold standards are discussed.
PRINCIPLES OF ULTRASONOGRAPHY Ultrasound Equipment Parameters When using an ultrasound scanner, it is important to understanding the basic physical principles so that the best parameters can be set to optimize the image quality and obtain the desired information. An ultrasound scanner obtains images by emitting a pulse of high-frequency sound and then measuring the echoes that reflect back from a boundary between two tissue structures. Sound information returning from organs and other tissues depends on the density of these structures. These echoes are electronically processed to produce images of these structures.
Probe Array
Initially, ultrasound probes were designed in a phased linear array, where parallel beams were generated in sequence to create a field as wide as the probe. Today, most probes are curvilinear (convex), where the beams diverge from a single point. This makes the probe more compact and provides a wider field of view. The first curvilinear probes mechanically moved the ultrasound beam through a pie-shaped sector ranging from 30 to 100 degrees. Modern probes use computer-controlled electronics to sweep the ultrasound beam. Today, most transabdominal and transvaginal probes use an electronic curvilinear array. Ultrasound Modes
Originally, ultrasound images were displayed in one dimension, referred to as either A-mode (amplitude mode) or M-mode (motion mode). M-mode is still used to analyze cardiac motion, where ultrasound echoes are displayed as a function of distance and time as parallel vertical lines progressing from left to the right. Today, most ultrasound images are displayed in two dimensions, referred to as B-mode (brightness mode). For this technique, also referred to as gray-scale, the axes of the display correspond to the physical coordinates of the object, and the intensity of each point on the display is proportional to the intensity of the reflected ultrasound. A recent technologic advance, termed three-dimensional (3D) ultrasonography, uses computer software to combine multiple B-mode images in successive planes into a three-dimensional image that displays volume. If multiple volume images are shown in rapid succession, a motion video is obtained, which is sometimes referred to as 4D ultrasonography, because it shows three dimensions over time.2 An additional ultrasound approach used clinically is termed color flow Doppler ultrasonography. For this approach, a standard B-mode image is overlaid with colors derived from Doppler sounds, which represent the speed and direction of blood flowing through vessels (Fig. 30-1). Frequency
Ultrasound frequencies used in gynecology can range from 1.6 to 10 MHz but are more commonly between 3 and 7.5 MHz. These frequencies are much higher than audible sound frequencies, which are less than 20,000 Hz. For ultrasound, lower frequency sound waves are better able to penetrate the body’s tissues more deeply.3 Conversely, higher frequency sound waves give better resolution but penetrate tissue less deeply.
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Section 5 Reproductive Imaging The transvaginal approach has become the preferred route for most gynecologic ultrasounds because this places the probe much closer to the pelvic organs. As a result, the images obtained are of much higher resolution than those obtained transabdominally. The disadvantage of this approach is that large (>15 cm) uterine or ovarian masses that extend outside the true pelvis are difficult to completely delineate. For this reason, a pelvic and abdominal examination should be performed to assess the size of the mass. If large, the session will start with a transabdominal approach, the patient will be asked to empty bladder, and a transvaginal approach may be performed, if necessary.
Ultrasonography Versus Sonohysterography
Figure 30-1 Color flow Doppler ultrasonography shows the typical appearance of the arcuate arteries that are found in the middle muscular layer of the myometrium.
The frequency of most ultrasound probes can be automatically changed by adjusting the depth of the focal zone corresponding to the structure being studied. Ideally, the highest frequency that can penetrate the depth to be studied should be utilized.4 Power and Gain
The power level refers to the amount of energy produced by the transducer; the gain refers to the amount of amplification of the returning sound waves. Increasing the power can improve the quality of the image but usually produces more artifacts. The gain should be adjusted to obtain the best overall brightness of the display image. Dynamic Range
Dynamic range is the range between the weakest and the strongest echoes displayed and is expressed in decibels (dB). A broad dynamic range results in the most favorable image characteristics. To minimize artifacts, the dynamic range should be set lower for cystic structures and higher for solid structures.5
APPROACHES
Transvaginal ultrasonography is the first step in evaluating the uterus, ovaries, and tubes. When a symmetric and regular endometrial stripe can be clearly imaged, the uterine cavity can be determined to be normal and endometrial thickness can be accurately determined. In contrast, when the endometrial stripe is irregular or poorly delineated, transvaginal ultrasonography alone has limited usefulness in evaluating the nature and location of endometrial cavity pathology.6–10 In these cases, sonohysterography greatly enhances the ability to visualize lesions that project into the uterine cavity. Sonohysterography enhances the diagnostic accuracy of transvaginal ultrasonography by filling the endometrial cavity with fluid (usually normal saline solution) via a transcervical catheter.11 First described by Nannini in 1981 as echohysteroscopy, this technique is also referred to as saline infusion sonography.12 Sonohysterography is a simple, accurate way to detect intrauterine masses that will ultimately be evaluated histologically to differentiate endometrial polyps, submucosal leiomyomas, and endometrial carcinoma.13 This technique has several advantages over X-ray hysterosalpingography, including less pain, less cost, and no exposure to ionizing radiation.
INDICATIONS Transvaginal ultrasound with or without sonohysterography is often one of the first diagnostic steps in the evaluation of a wide spectrum of gynecologic and obstetric conditions that can result from or cause anatomic alterations of the reproductive organs (Table 30-1). The excellent diagnostic accuracy, minimal invasiveness, and relative cost-effectiveness of these techniques have led to their widespread acceptance.
Transabdominal versus Transvaginal Ultrasonography
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Two methods are commonly employed to obtain a sonogram of pelvic organs in women: transabdominal (abdominal) and transvaginal (vaginal or endovaginal). Modern ultrasound scanners are equipped with probes and imaging options to perform both techniques. The transabdominal approach was the first to be used. The disadvantage of this approach is decreased resolution due to lower frequency of the probe needed to penetrate the abdominal wall. The probe is necessarily further away from the pelvic organs compared to the transvaginal approach, and the patient has the discomfort of a full urinary bladder as the ultrasonographer presses the transducer firmly against the skin.
Pelvic Mass Probably one of the most common indications for pelvic ultrasonography is evaluation of a pelvic mass detected on examination. The origin of the mass, usually from the uterus or ovary, can easily be determined in most cases. In some cases, the pelvic mass will be demonstrated to be nongynecologic. Ovarian Masses: Functional, Benign, or Malignant
Ovarian masses can usually be characterized as functional or neoplastic based on size and persistence over time. Masses greater than 6 cm and those persisting longer than 2 months are unlikely to be functional regardless of appearance.
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Chapter 30 Pelvic Ultrasonography and Sonohysterography Table 30-1 Clinical Indications for Ultrasonography and Sonohysterography Ultrasonography Pelvic mass
Sonohysterography
X
Pelvic pain
X
Pelvic inflammatory disease
X
Lost intrauterine device
X
Infertility
X
X
Recurrent pregnancy loss
X
X
Abnormal uterine bleeding
X
To evaluate indistinct endometrium
X X
To evaluate thickened endometrium
X
To monitor tamoxifen therapy
X
To predict depth of endometrial cancer invasion
X
Uterine leiomyomata Intramural and pedunculated Submucosal and intracavitary
X X
Intraoperative sonohysterography
X
To disperse intrauterine adhesions
X
Certain sonographic characteristics have been found to be strongly associated with malignancy. An ovarian mass is more likely to be malignant when ultrasonography reveals: ● ● ● ● ● ●
multiloculated cysts thick septations solid areas papillae bilateral lesions ascites
These criteria are used in combination with measurements of serum CA 125 for the risk of malignancy index.14 For indeterminate cases, color flow Doppler ultrasonography may also be helpful. It has been demonstrated that ovarian malignancy is more likely if a solid element of the mass demonstrates central blood flow.15 Ovarian Torsion
Ovarian torsion is a relatively common gynecologic surgical emergency. The average age of occurrence is 26 years, and 20% of these cases occur during pregnancy. Patients most commonly present with sudden onset of severe unilateral lower abdominal pain that often radiates to the back or groin. This can be intermittent and recurring. In the worst case, it is associated with nausea and vomiting. Pelvic examination usually reveals a tender adnexal mass. The sonographic findings for ovarian torsion include a cystic, solid, or complex mass that is frequently found in the midline superior to the uterus.16 This mass, which represents an enlarged ovary, will often have cystic follicles visible along the periphery and a markedly thickened wall. Increased peritoneal fluid is common. Color flow Doppler ultrasonography findings vary depending on the degree and duration of twisting of the ovarian pedicle. With multiple turns about the pedicle and in chronic cases, Doppler will show no flow in the ovary. If lesser degrees of torsion or venous thrombosis result in occlusion of the veins but
Figure 30-2 Sonohysterogram (SIS) of leiomyoma (FIB) that clearly shows that more than 50% is located within the myometrium.
not arteries, arterial waveforms and color flow will be seen, often with a characteristic whirlpool sign of coiled twisted vessels. Uterine Leiomyomas
Uterine leiomyomas are the most common indication for hysterectomy in the United States. Although approximately 25% of women will have symptomatic uterine leiomyomas, the cumulative incidence of leiomyomas by age 50 is nearly 70% for white women and more than 80% for black women.17 The classic sonographic appearance of a uterine leiomyoma is a spherical hypoechoic or hyperechoic area contiguous with the uterine wall.18 In some cases, calcification of leiomyomas results in irregular high-amplitude echoes. In many cases, it is difficult with transvaginal ultrasonography alone to determine whether a leiomyoma is intramural, submucosal, or intracavitary in location. Sonohysterography can accurately identify the size, location, and depth of uterine leiomyomata (Fig. 30-2).19 This information helps predict surgical resectability, the best access for surgery (abdominal versus hysteroscopic), and the duration of surgery. For surgical planning, uterine leiomyomas are classified into three types: ●
●
●
Class 1: complete submucosal involvement with no myometrial involvement (intracavitary) Class 2: submucosal component involving less than half of the myometrium Class 3: submucosal involvement with an intramural component of greater than 50%.
Class 3 leiomyomas are the least amenable to successful resection and are associated with significantly more complications, including uterine perforation, fluid overload, and incomplete resection.20
Pelvic Pain Pelvic pain is a common gynecologic complaint, accounting for 10% of gynecologic office visits, 40% of laparoscopies, and 15% of hysterectomies in the Untied States.21 Ultrasonography is an
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Section 5 Reproductive Imaging 94% and 80%, respectively.23 In women with abnormal bleeding after an abortion or delivery, ultrasonography can sometimes determine the cause of abnormal bleeding to be retained products of conception.24,25 Endometrial cancer is an uncommon cause of bleeding in women younger than age 40. Endometrial thickness is not very discriminatory in premenopausal women. This is in contrast to postmenopausal women, in whom endometrial thickness greater than 5 mm is cause for concern. During a normal menstrual cycle, endometrial thickness normally varies from 5 to 12 mm.26,27 Sonohysterography can be extremely helpful in these cases. Postmenopausal Women
Figure 30-3
Hydrosalpinx. A hypoechoic tubular structure.
important part of the initial workup for patients who present with pelvic pain to identify anatomic causes. In nonpregnant women, ultrasonography can sometimes identify causes, such as hemorrhagic ovarian cysts, ovarian torsion, tubo-ovarian abscesses, or degenerating uterine leiomyoma.
Pelvic Inflammatory Disease Pelvic ultrasonography can be extremely helpful for the evaluation of women with a clinical diagnosis of pelvic inflammatory disease.22 In most patients, ultrasonography will be normal, because normal and inflamed fallopian tubes are not sonographically distinct. Some patients will have acute or chronic abnormalities that are sonographically visible, such as a pyosalpinx, hydrosalpinx, tubo-ovarian abscess, or tubo-ovarian complex (Fig. 30-3).
Lost IUD A lost IUD is diagnosed when the strings cannot be visualized protruding through the cervix. If the strings cannot be found within the cervical canal, either the strings have retracted into the uterine cavity or the IUD is no longer in the uterine cavity because it has perforated the uterine wall or has been unknowingly expelled. Alternatively, retraction of the IUD strings into an enlarging uterus can be the first sign of pregnancy. The first step in locating a lost IUD is ultrasonography. An IUD produces a characteristic acoustic shadow. If the IUD is located within the uterine cavity, sonohysterography can often determine if the IUD is embedded in the myometrium.
Abnormal Uterine Bleeding Premenopausal Women
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Transvaginal ultrasonography is a useful diagnostic test in the premenopausal woman who presents with abnormal bleeding. The vast majority of premenopausal bleeding is the result of anovulatory uterine bleeding. Other common causes include submucosal leiomyoma and endometrial polyps, which can be detected by ultrasonography with sensitivity of approximately
Evaluation of abnormal uterine bleeding in postmenopausal women is extremely important to exclude endometrial cancer, because almost 10% will ultimately be found to have a malignancy.28 Endometrial cancer occurs in 1 to 2 per 1000 postmenopausal women per year and is one of the most common cancers in the female, exceeded in frequency only by cancers of the breast, colon, and lung. Thus, all postmenopausal women with abnormal uterine bleeding should undergo a thorough evaluation. Evaluation of Abnormal Uterine Bleeding
Historically, the standard diagnostic procedure has been dilation and curettage (D&C) with or without hysteroscopy. Today, this is often replaced by outpatient endometrial sampling via a suction device. Unfortunately, blind sampling will miss a significant number of focal lesions. Suction sampling devices are useful for detecting global disease but frequently are inadequate for detecting disease localized to a focal area or a polyp. Studies demonstrate that 15% or less of the endometrial cavity is sampled using suction devices.29 Although sampling with a suction device will provide adequate tissue for pathologic evaluation in as many as 97% of cases, carcinoma confined to endometrial polyps and localized tumors will be missed more than 15% of the time.30 For this reason, many clinicians advocate sonographic evaluation of the endometrium before endometrial biopsy to exclude focal lesions. Ultrasonography Versus Sonohysterography
Ultrasonography and sonohysterography are sensitive noninvasive methods for detecting focal intrauterine lesions, which usually indicate carcinoma, hyperplasia, polyps, and submucosal uterine fibroids.31–36 The incidence of polyps and submucosal uterine fibroids in symptomatic premenopausal women is 33% and 21%, respectively.37 If ultrasonography or sonohysterography reveals a focal lesion, this should be evaluated with a hysteroscopy/D&C rather than with a blind endometrial biopsy, because ultrasonography cannot accurately identify the nature of the lesion. The sonographic appearance of a symmetric endometrial echo indicates that there are no focal lesions present. To reliably assess endometrial thickness, the endometrial echo must be completely seen in a longitudinal axis, surrounded by an intact hypoechoic junctional zone. The predictive value of endometrial thickness will be decreased in the presence of coexisting pathology, which can distort the endometrium or extreme angulation of the uterus.
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Chapter 30 Pelvic Ultrasonography and Sonohysterography Figure 30-4 Algorithm for management of postmenopausal vaginal bleeding.
Postmenopausal bleeding
Transvaginal sonography
Asymmetric endometrium > 5mm
Symmetric endometrium ≤ 5mm
Sonohysterography
No focal lesion
Focal lesion
Endometrial biopsy
Normal endometrium
Endometrium ≤ 5 mm
Surveillance
Abnormal endometrium
Insufficient tissue
Endometrium > 5 mm
If bleeding persists
Several studies have suggested that in postmenopausal women, endometrial thickness up to 5 mm makes endometrial pathology (i.e., endometrial hyperplasia or carcinoma) extremely unlikely, and some clinicians will therefore omit an endometrial biopsy.38 This cutoff is only useful in postmenopausal women who are not taking postmenopausal hormones such as estrogen or tamoxifen. It is also important to remember that using sonographic thickness of the endometrium to exclude endometrial carcinoma in postmenopausal women with bleeding is not 100% accurate regardless of the cutoff used. How accurate is endometrial thickness in predicting carcinoma? Meta-analyses indicated that carcinoma will be found in approximately one third of postmenopausal women with bleeding whose endometrial thickness is greater than 5 mm.39 When the endometrium is equal to or less than 5 mm, only 2% to 7% will subsequently be found to have carcinoma.39,40 Reducing the cutoff to 4 mm will decrease the risk of carcinoma to 1.2%.41 Because endometrial carcinoma is a curable disease when discovered early, most clinicians will perform an initial endometrial biopsy in postmenopausal women with bleeding, regardless of endometrial thickness (Fig. 30-4). If the biopsy of a patient with an endometrial thickness of 5 mm or less returns as “quantity not
Hysteroscopydilation and curettage
sufficient for diagnosis,” continued surveillance is a reasonable approach. Sonohysterography
Sonohysterography is much more effective than transvaginal ultrasound alone to detect endometrial pathology in women with abnormal uterine bleeding and thickened endometrium. In addition to clearly demonstrating the location of intracavitary lesions, sonohysterography allows for differentiation of isolated submucosal defects from more diffuse endometrial thickening.19,42–44 One study of 199 postmenopausal women with abnormal bleeding found that whereas only 7% were found to have endometrial abnormalities on transvaginal ultrasound, more than 34% had abnormalities detected by sonohysterogram.45 In the past, the initial step in the evaluation of a woman with postmenopausal bleeding was an office endometrial biopsy. However, this procedure is notoriously inaccurate in the presence of focal endometrial pathology. In one study, 148 postmenopausal women with abnormal bleeding underwent aspiration endometrial biopsy, followed by sonohysterography whenever the endometrial thickness was greater than 5 mm.46 Sonohysterography discovered 45 focal lesions in 81 women, 5 of which were
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Section 5 Reproductive Imaging determined to be malignancies by hysteroscopy. The initial endometrial biopsy missed 41 of these focal lesions and 3 of the 5 malignancies. The take-home message is that a blind endometrial biopsy should be avoided in women determined to have focal lesions because they often miss the pathology. Sonohysterography is as accurate as hysteroscopy for the detection of focally growing lesions, with sensitivities for both of approximately 96%.47 However, neither modality can reliably discriminate between benign and malignant focal lesions. For this reason, histologic tissue evaluation is required whenever intrauterine pathology is discovered. The evaluation of postmenopausal women with abnormal bleeding should utilize a combination of transvaginal ultrasonography, sonohysterography, or office endometrial biopsy when indicated, and hysteroscopy for women found to have focal lesions or abnormal biopsies (see Fig. 30-4). Utilizing ultrasonography before endometrial biopsy will avoid this uncomfortable test in women found to have focal lesions because they require a directed biopsy instead. This combination of sonohysterography and endometrial biopsy has been found to have a sensitivity of 97%, a specificity of 70%, a positive predictive value of 82%, and a negative predictive value of 94%.46 Breast Cancer Patients Receiving Tamoxifen
Tamoxifen, a selective estrogen receptor modulator, is a commonly used adjunctive therapy for women with breast cancer. Although tamoxifen acts as an estrogen antagonist in the breast, it acts as an estrogen agonist in the genital tract and is associated with endometrial hyperplasia and carcinoma. Patients taking tamoxifen have a 27% risk of developing endometrial polyps, a 9% risk of endometrial hyperplasia, and a rate of endometrial cancer two to three times higher than that of age-matched women.48,49 Neither transvaginal ultrasonography nor sonohysterography are effective screening tools in women using tamoxifen because of tamoxifen-induced subepithelial stromal hypertrophy.50–52 As a result of this abnormality, there is a poor correlation between ultrasonographic measurements of endometrial thickness and abnormal endometrial proliferation or endometrial carcinoma.53–55 Women taking tamoxifen should be monitored for symptoms of endometrial hyperplasia or cancer (e.g., abnormal uterine bleeding) and undergo a gynecologic examination at least yearly.56 However, because ultrasonographic screening has not been found to be effective, it is not recommended. When a women taking tamoxifen experiences abnormal uterine bleeding, sonohysterography appears to be the most appropriate next step.57 Surgery can be avoided in approximately 14% of women who will be found to have normal endometrium with or without subendothelial cysts. The remainder of women will have focal lesions and should undergo hysteroscopically directed biopsies, because a blind endometrial biopsy in the office will often miss lesions.57
Screening of Asymptomatic Women Premenopausal Women
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Some clinicians recommend screening asymptomatic women with transvaginal ultrasonography, sonohysterography, or endometrial biopsy.58 One study found that approximately 10% of asymptomatic premenopausal women have uterine polyps and 1% have intracavitary fibroids, compared to 33% and 21% of
symptomatic women, respectively.59 However, it is uncertain how much of this pathology is actually associated with health risks and how much will regress spontaneously.60 The concern is that such screening is likely to lead to some unnecessary surgical intervention. Until more information is available, universal screening is not recommended.61 Postmenopausal Women
Transvaginal ultrasound has not been shown to be a useful screening test in asymptomatic postmenopausal women regardless of their use of hormone treatment. One study reported that more than 35% of asymptomatic postmenopausal women have focal endometrial pathology by sonohysterography.45 Although the incidence of endometrial pathology in postmenopausal women with bleeding is relatively high, the incidence of life-threatening focal endometrial lesions in asymptomatic women is likely to be low.61 More importantly, the discriminatory value of endometrial thickness is lost in these asymptomatic women. One study of 448 postmenopausal women, half of whom were receiving estrogen replacement therapy, found that although endometrial thickness less than 5 mm was highly predictive of normal endometrium (negative predictive value, 99%), endometrial thickness greater than 5 mm was unlikely to indicate pathology (positive predictive value, 9%).60 A study of 1926 asymptomatic postmenopausal women showed similar results using a 6 mm threshold for endometrial thickness.63 Screening asymptomatic postmenopausal women is not currently recommended.
Endometrial Carcinoma Detecting Endometrial Carcinoma
Sonography and sonohysterography can detect abnormalities of the endometrium but cannot accurately distinguish between malignant and benign lesions. With transvaginal ultrasonography, endometrial carcinoma usually appears to be either diffusely or partially echogenic. With sonohysterography, endometrial carcinoma appears as irregularly thickened endometrium or a discrete mass, but is indistinguishable from endometrial hyperplasia.11,42 A poorly distensible endometrial cavity noted during sonohysterography can be a sign of endometrial cancer.64 In the case of polyps, Doppler flow ultrasonography is of little help in distinguishing between the majority of benign polyps and those that are malignant.65 Predicting Depth of Invasion
Histology, tumor grade, depth of myometrial invasion, and tumor size are well known prognostic factors for lymph node metastasis by endometrial cancer but are difficult to predict preoperatively.66,67 Magnetic resonance imaging is effective in predicting the depth of myometrial invasion and endometrial cancer tumor size but is expensive and is not universally available. An alternative approach is sonohysterography to determine the depth of endometrial invasion; patients with deeply invasive disease can be referred to a gynecologic oncologist. After endometrial carcinoma has been diagnosed histologically on biopsy, sonohysterography has been suggested as a way to accurately determine the degree of myometrial invasion.68 In a small study of 19 endometrial adenocarcinoma patients, sonohysterography performed before hysterectomy was able to predict the exact depth of myometrial invasion in 15 (94%) cases,
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Chapter 30 Pelvic Ultrasonography and Sonohysterography suggesting a potential role for this technique in preoperative staging of endometrial carcinoma. More studies are necessary before widespread application of this approach. Risk of Disbursing Malignant Cells
There is a concern that procedures that distend the uterus with fluid media (i.e., hysteroscopy, hysterosalpingography, and sonohysterography) could flush malignant endometrial cells into uterine vessels or through the tubes into the peritoneal cavity, thus adversely affecting the prognosis for patients with endometrial carcinoma. One study of hysterograms in patients with endometrial cancer found no correlation between intravasation of contrast medium into lymphatics and veins and subsequent 5-year survival rates.69 A sonohysterogram study of women with stage I endometrial carcinoma showed that infusion of 10 to 20 mL of saline solution resulted in saline spillage from the fallopian tubes in 5 of 14 patients; in 1 patient this fluid contained malignant cells.70 These findings suggest that sonohysterography might have a small risk of cancer dissemination, although the prognostic significance of flushing endometrial cancer cells in the peritoneal cavity remains uncertain. Additional studies are warranted.
Figure 30-5 Polycystic ovary. Typically there are more than 10 peripherally located small follicles (2 to 8 mm in diameter) and increased central dense stroma.
Infertility and Recurrent Pregnancy Loss Initial Evaluation
Abnormalities related to the uterus or fallopian tubes are present in a large number of infertile women. For the infertile patient, hysterosalpingogram (HSG) has traditionally been the first step in evaluation of the uterine cavity and tubes. Surgical evaluation with laparoscopy or hysteroscopy is used when intra-abdominal pathology is suspected or when all other diagnostic tests are normal. Recent investigations have suggested that pelvic ultrasonography and sonohysterography might also be valuable in the assessment of the infertile woman. Transvaginal ultrasonography, with sonohysterography when indicated, is a useful diagnostic procedure for the initial evaluation of infertile patients.71 Congenital and acquired uterine pathology is present in up to 10% of infertile couples and 15% to 55% of those with recurrent pregnancy loss. Pathologic conditions of the uterus that can be detected with ultrasonography and sonohysterography include müllerian and diethylstilbestrol-related anomalies, uterine fibroids, endometrial polyps, and Asherman’s syndrome. Other fertility-related conditions that can be detected include hydrosalpinges (see Fig. 30-3) and polycystic ovaries (Fig. 30-5). Sonohysterography can be used to thoroughly evaluate the endometrial cavity and has been shown to be as accurate as diagnostic hysteroscopy in detecting pathology. In a study of 72 infertile women, 11% were found to have cavitary lesions with both HSG and hysteroscopy; there was no statistical difference in pregnancy outcome between these two techniques for uterine evaluation.72 Recurrent Pregnancy Loss
The diagnosis and surgical correction of uterine defects associated with recurrent pregnancy loss increases the rate of full-term delivery. Anatomic disorders, including congenital müllerian anomalies and acquired defects such as uterine leiomyomata and uterine synechiae, account for 15% to 55% of recurrent pregnancy loss.73
Figure 30-6 Bicornuate uterus. Two endometrial echoes represent two separate cavities of a müllerian anomaly that ultimately proved to be a bicornuate uterus.
Prior to the development of ultrasonography, HSG was the diagnostic test of choice for uterine anomalies. However, HSG is not effective in assessing the outer uterine contour, and thus cannot accurately discriminate between a septate and a bicornuate uterus.73,74 In the case of uterus didelphys with a complete vaginal septum covering one of the two cervical openings, cannulation of only one cervical canal during HSG can lead to the misdiagnosis of a unicornuate uterus.75 Transvaginal ultrasonography is more accurate than HSG in diagnosing müllerian anomalies, because it can detect structures not visible externally, such as noncommunicating uterine horns, and can determine both the internal and external contours of the uterus.76 An important function of ultrasonography is to differentiate between a uterine septum and a bicornuate uterus (Fig. 30-6). The diagnosis of bicornuate uterus is made in the presence of fundal notch deeper than 1 cm, diverging endometrial cavities, and fundal broadening of the intracavitary tissue, which
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Section 5 Reproductive Imaging is typically thick and isoechoic relative to the rest of the myometrium.77 A uterine septum is usually thinner and hypoechoic because it tends to be more fibrous. However, hypoechogenicity is not diagnostic, because the septum can contain both fibrous and muscular elements.78 Sonohysterography appears to be an even better screening tool in patients with a history of recurrent pregnancy loss, and in one study was twice as accurate as either HSG or ultrasonography alone.74 Sonohysterography has been reported to demonstrate a variety of other uterine cavity defects, including müllerian anomalies, in up to 50% of these patients.79 Three-dimensional (3D) ultrasonography has been shown to be useful in the diagnosis of müllerian anomalies.80 The presence of leiomyomas can obscure the view and decrease the sensitivity of 3D ultrasound. The best image is obtained when the scan is performed during the luteal phase. A normal external fundal contour or one with less than 10 mm indentation is consistent with a septate uterus. Fallopian Tube Evaluation
Sonosalpingography has been used to determine tubal patency by sonographically observing saline or sonographic contrast media as it traverses the tubes. Some studies have shown this technique to be as accurate as HSG in determining tubal patency, especially when used in conjunction with Doppler ultrasound.81 To perform sonosalpingography, it is necessary to occlude the cervical canal with a balloon catheter to block egress of fluid from the uterine cavity. The approximate location of the fallopian tube is best estimated to be where the tube inserts into the uterine cornua on transverse view. Tubal patency is diagnosed when saline solution is seen surrounding the ovary. If there is any doubt about tubal spill, a solution that enhances sonographic contrast can be used. Human albumin (Albunex, Mallinckodt, St. Louis) or lactose particles suspended around microbubbles (Echovist, Schering, Berlin) provide excellent sonographic contrast to document tubal patency and spillage.82 The safety of Albunex has been established in multiple studies, but it should only be used in selected cases secondary to cost and refrigeration storage requirements. Air bubbles can also be used as an inexpensive and reasonably accurate first-line sonographic contrast to determine tubal patency.83 After the uterine cavity is evaluated with saline solution, small amounts of air are insufflated. These bubbles are easily seen sonographically. Air-contrast sonohysterography and laparoscopy showed agreement in 79.4% of patients, with a sensitivity of 86% and specificity of 77.2%.
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detection of cervical pathology before starting the cycle is important, because difficult embryo transfer adversely affects outcomes in women undergoing IVF.84 Likewise, preexisting intrauterine pathology that might decrease subsequent pregnancy rates can be detected and treated. In one study, 80 women planning to undergo IVF with ovum donation were prescreened with sonohysterography; 38% were found to have pathology subsequently confirmed at hysteroscopy.85 Controlled Ovarian Hyperstimulation and In Vitro Fertilization
Pelvic ultrasonography is invaluable for monitoring the ovarian and endometrial response to ovulation induction using exogenous gonadotropins. The primary purpose of ultrasonography during controlled ovarian hyperstimulation is to monitor the size and growth of ovarian follicles because subsequent pregnancy rates are predicted by follicle number and size. When hyperstimulation is performed before IVF, studies have suggested a relationship between follicle size and oocyte quality. For these purposes, sonographically measuring the oocytes in two dimensions (rather than three) appears to be sufficient. Endometrial thickness and pattern determined sonographically can also predict subsequent pregnancy outcomes. Endometrial thickness greater than 6 mm has been associated with higher implantation and pregnancy rates and lower miscarriage rates in some studies.86,87 However, this relationship remains controversial, because other studies have reported no predictive value of endometrial thickness.88–92 Sonographic endometrial patterns are also important. Proliferative endometrium appears as a triple layer (Fig. 30-7). There are three distinct regions: the central echogenic line, the outer hyperechoic line, and the hypoechoic region between the two lines. In the luteal phase, the endometrium becomes uniformly hyperechoic (Fig. 30-8). A hyperechoic endometrium immediately before ovulation is associated with a lower pregnancy rate. The multilayered pattern is clearly associated with a higher pregnancy rate.88 An important use of transvaginal sonography is to guide transvaginal retrieval of oocytes for IVF. Prior to the development of transvaginal ultrasound, oocytes were necessarily retrieved laparoscopically for this procedure. A final use of sonography in IVF is for embryo transfer. A large, prospective, randomized study found that the pregnancy rate was significantly higher among the ultrasound-guided group (50%) compared with the clinical touch group (34%).93 Today, most IVF programs utilize this approach.
Pregnancy
Before Assisted Reproductive Technologies
Viability and Location
Before initiation of an in vitro fertilization (IVF) cycle, it is important to predict the ovarian response and potential pregnancy rate. Most centers use a day 3 serum follicle-stimulating hormone (FSH) and estradiol level and possibly a clomiphene challenge test. Another parameter used to predict success is the antral follicle count (AFC). An early follicular phase transvaginal ultrasound is performed to measure the number of antral follicles. Typically between 11 and 12 antral follicles are found. Although no specific cutoff is found, the AFC is correlated with the number of oocytes aspirated. Many fertility centers also evaluate all patients with sonohysterography before embryo transfer subsequent to IVF. The
Probably one of the most important uses of first-trimester ultrasound is to determine the viability and location of a pregnancy in women at increased risk of miscarriage or ectopic pregnancy. This most commonly includes women in the first months of pregnancy with vaginal bleeding and pain or those with a prior history of early spontaneous abortion or ectopic pregnancy. It also includes women who have been treated for infertility, because the risk of ectopic pregnancy is higher in this group as well. It is important to establish the number of viable embryos in women who have been treated with oral or injectable medications to induce ovulation or who have undergone transfer of multiple
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Chapter 30 Pelvic Ultrasonography and Sonohysterography Figure 30-7 Follicular phase endometrium showing the classic three-layer appearance.
Establishing a Due Date
Accurate determination of the due date is critical for appropriate management of the third trimester of pregnancy. However, many women have a menstrual history that is inadequate to accurately establish gestation age and due date. This could be related to a history of irregular menses, conception while using contraceptive pills, or uterine size by examination that is inconsistent with the last menstrual period. Liberal use of firsttrimester ultrasonography has become an important tool in modern obstetrics because first-trimester sonographic gestational age estimates are more accurate than subsequent sonographic estimates. Obstetric Ultrasound
Figure 30-8
Luteal phase endometrium is uniformly hyperechoic.
embryos after IVF. These assisted reproductive technologies (ARTs) are associated with multiple gestation rates ranging from 5% to 35%, depending on the specific approach used. One or more intrauterine sacs effectively exclude the possibility of an ectopic pregnancy in most women, although the chances of a heterotopic pregnancy after IVF is as high as 1 in 100 pregnancies. When an amorphous adnexal mass is observed sonographically, it is important to determine if it is an ectopic pregnancy, especially in the absence of an intrauterine sac. Color flow Doppler ultrasonography will clearly identify some amorphous adnexal masses as an ectopic pregnancy based on the characteristic blood flow pattern.
Transabdominal ultrasonography is used to evaluate fetal status after the first trimester as the gravid uterus increases in size and rises from the pelvis. The substantial obstetric benefits of this invaluable diagnostic modality are beyond the scope of this chapter.
Other Therapeutic Application Operative Sonohysterography
Ultrasound-directed biopsy for submucosal pathology has been reported as a cost-effective alternative to hysteroscopy. One technique involves insertion of a #3 French loop or finger-like grasper through an access catheter under sonohysteroscopic guidance.94 This approach is hampered by the instrument’s small size and limited rotational ability. Another technique uses a loop snare to resect intrauterine abnormalities under sonohysteroscopic guidance.95 For this technique, a #12 French intrauterine access catheter with a 3-mL balloon (Cook OB/GYN, Spencer, Ind.) is placed through the
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Section 5 Reproductive Imaging cervical canal. A #5 French echogenic loop snare is then passed through the access catheter to perform the resection mechanically. The reported time required for resection of polyps ranged from 18 to 43 minutes. This technique is difficult in patients with cervical stenosis, which precludes insertion of the operative instruments, and for removal of cornual lesions. More research is required before widespread clinical application of these techniques. Tubal Cannulation during Sonosalpingography
Some therapeutic procedures may be possible during sonosalpingography. One report details hysteroscopic proximal tubal cannulation with concomitant intraoperative ultrasound-guided visualization of the fallopian tubes using Albunex after having failed fluoroscopic cannulation.41 In select cases, this could obviate the need for laparoscopy. Intraoperative Sonohysterography
Ultrasonography can be used as an intraoperative aid for multiple transvaginal procedures, many of which had to be done blindly in the past.96–98 During difficult dilations secondary to cervical stenosis and during hysteroscopic resection of extensive intrauterine synechiae, sonographic visualization of the uterus can decrease the risk of uterine perforation. Likewise, during uterine curettage for spontaneous and induced abortion, ultrasonography can be used to prevent or detect uterine perforation and to ensure complete removal of the products of conception. During the hysteroscopic removal of impacted foreign bodies (e.g., intrauterine devices), ultrasonography can locate the foreign body and decrease the risk of perforation. Finally, for intracavitary radiation treatment of endometrial cancer, ultrasonography can aid in the correct placement of the intrauterine tandem apparatus. Sonohysterography can also be used as an interoperative adjunct during operative hysteroscopy and laparotomy. The most common uses may be to ensure complete removal of deep intramural myomas adjacent to the endometrial cavity, to decrease the chance of uterine perforation during intrauterine resection, and to clarify confusing visual findings during hysteroscopy.41
The long-term effects of ultrasound during pregnancy continue to be closely scrutinized because the developing brain is the tissue most vulnerable to biologic damage. Fortunately, no study to date has been able to detect impaired neurologic development in children exposed to prenatal ultrasound.100 Sonohysterography has the potential risks of infection, bleeding, and perforation associated with introduction of instruments (catheters) and media (usually sterile saline solution) into the uterine cavity. The risk of infection after sonohysterography has been reported to be less than 1%, and no cases of serious bleeding or perforation have been reported.101 Analogous to HSG, prophylactic antibiotics should be used for patients undergoing sonohysterography with a history of pelvic inflammatory disease or hydrosalpinges. The regimen commonly used for HSG is doxycycline (100 mg bid) beginning 2 days before sonohysterography and continued for 3 days afterward. Patients at risk for subacute bacterial endocarditis should be given prophylactic antibiotics.
TECHNICAL CONSIDERATIONS Premedication Antibiotics
Transvaginal ultrasonography requires no prophylactic antibiotics. Prior to sonohysterography prophylactic antibiotics should be given to patients with a history of pelvic inflammatory disease or hydrosalpinges and those at risk for development of subacute bacterial endocarditis. Analgesics
Transvaginal ultrasonography does not requires special analgesics. Likewise, sonohysterography does not requires special analgesics if a balloon catheter is not used to occlude the cervix because uterine distension is minimal using this technique. When a balloon catheter is used, both the balloon and the subsequent uterine distension result in uterine cramping analogous to that seen with HSG. In these cases, routine use of a nonsteroidal anti-inflammatory drug (NSAID) 30 minutes before the procedure is recommended to reduce discomfort.
Pressure Lavage under Ultrasound Guidance
Pressure lavage under ultrasound guidance (PLUG) has been described in a series of seven patients as method for the treatment of secondary amenorrhea due to intrauterine adhesions.99 Continuous transcervical injection of saline solution was used to mechanically disrupt these intrauterine adhesions. This technique satisfactorily disrupted mild adhesions in five patients but was unable to disrupt moderate adhesions in two patients. Menses were restored in all seven patients, and two of the three previously infertile patients attempting pregnancy were successful. Further controlled studies are needed to determine the relative value of this approach.
RISKS
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Pelvic ultrasonography appears to be virtually risk-free in the nonpregnant patient. Although high-intensity ultrasound can damage biologic tissue by causing a rise in temperature and cavitation, the levels used clinically have never been shown to damage pelvic organs.
Timing in the Cycle Pelvic ultrasonography is performed throughout the menstrual cycle, depending on indication. However, when searching for endometrial defects, it is important to scan during the follicular phase when the endometrium is hypoechoic and will serve as a contrast to echogenic polyps and fibroids. During the luteal phase, the endometrium assumes the same echogenicity as polyps, and this contrast disappears.102 Sonohysterography should also be performed in the first half of the follicular phase (days 4 to 10) after the cessation of bleeding. Not only are intracavitary lesions more easily seen on the background of a thin proliferative phase endometrium, but early pregnancy can also be best avoided by this approach. Sonography can be performed in the presence of uterine bleeding, where the blood sometimes provides a good endometrial–myometrial interface referred to as a spontaneous sonohysterogram.13 Unfortunately, blood or clots can also be misinterpreted as pathology such as polyps or adhesions; thus it is recommended to avoid the procedure if possible when a
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Chapter 30 Pelvic Ultrasonography and Sonohysterography patient is bleeding heavily.103 If the study is performed during bleeding and small lesions (<10 mm) are seen, repeating the examination during a bleeding-free interval is advisable.
Vaginal Ultrasonography For this procedure, the patient is placed in a dorsal lithotomy position after having emptied her bladder. Ultrasound gel is place on the transducer, a protective cover is placed over the transducer, and the cover is lubricated with a small amount of gel. The transducer is inserted into the vagina in a manner similar to that used when placing a vaginal speculum. Evaluation of the pelvis under ultrasound is best done in a systematic fashion to provide a complete survey of pelvic anatomy. The uterus should be carefully assessed in both longitudinal and transverse axes for the presence of anomalies of the cervix and the uterus. In particular, the size and number of all intramural and submucosal leiomyomata, any suspected endometrial polyps, and uterine malformations should be described. The position and configuration of the uterus should be determined. The length of the uterine cavity, whether the fundus is positioned anterior or posterior, and any degree of uterine flexion is useful information when subsequently performing endometrial sampling or intrauterine insemination. Normal fallopian tubes can rarely be seen with routine ultrasonography. When the tubal lumen can be identified, this strongly suggests pathology. A hypoechoic tubular structure is highly suggestive of distal tubal obstruction or hydrosalpinx. The ovaries should be measured in three perpendicular dimensions. These structures can usually be visualized posterior and lateral to the uterus and anterior to the internal iliac artery and vein. The iliac vessels provide an anatomic landmark for localizing the ovaries, because they can usually be found medial to these vessels. Ovaries cannot always be identified in postmenopausal women. During the reproductive years, ovaries can usually be identified by their typical follicular appearance. The normal functioning ovary often has multiple preantral follicles 2 to 10 mm in diameter. Multiple preantral follicles along the outer edge of the ovarian cortex (string of pearls pattern) is often seen in women with polycystic ovary syndrome but can also be seen in up to 10% of women who appear to be ovulating regularly (see Fig. 30-5).104 The number of visible preantral follicles count correlates with subsequent ovarian response to controlled ovarian hyperstimulation.105 Transitory simple or complex ovarian cysts up to 6 cm in diameter often represent functional cysts, including persistent unruptured follicles and corpora lutea cysts. It is important to measure the presence and amount of any free intraperitoneal fluid visible in the posterior cul-de-sac. A small amount can be a normal finding in women at any time during the menstrual cycle, especially immediately after ovulation. Increased intraperitoneal fluid is seen with hemoperitoneum, ovarian hyperstimulation syndrome resulting from ovulation induction, and most ominously when ovarian malignancies have resulted in ascites. Some physicians use transvaginal ultrasound to augment the standard bimanual pelvic examination. While ultrasonically visualizing the pelvic structures with the transvaginal probe, the physician can use the nondominant hand to apply counterpressure transabdominally. This technique can help mobilize and better define pelvic structures and assess any pelvic tenderness.
Figure 30-9 Goldstein sonohysterography catheter (Cook Ob/Gyn, Spencer, Ind.).
Figure 30-10 H/S Elliptosphere catheter with latex-free urethane. (Cooper Surgical Inc., Turnbull, Ct.)
Sonohysterography Catheter Choices
Catheter choices differ according to stiffness, presence or absence of a balloon, and cost.106 The simplest catheter is a semirigid #5 French pediatric feeding tube. A similar device equipped with a cone designed to partially occlude the external os is the Goldstein sonohysterography catheter (Cook Ob/Gyn, Spencer, Ind.), which has been associated with the least patient discomfort in one study (Fig. 30-9).106 Patients with latex allergy can be safely evaluated with the H/S Elliptosphere catheter with latex-free urethane (Akrad Laboratories, Cranford, N.J.) (Fig. 30-10).
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Section 5 Reproductive Imaging A balloon catheter is sometimes required to allow adequate distension of the endometrial cavity in patients with patulous or incompetent cervices or those with enlarged uteri.107 The least expensive balloon catheter is a #8 French pediatric Foley catheter, but it is also the most difficult to correctly place because of its lack of stiffness. A #5 French catheter with a 2-mL balloon is commercially available from several companies. Using a balloon catheter results in discomfort not unlike that experienced with an HSG, related both to the intracervical balloon and the distension of the uterus. Pretreatment with NSAIDs will minimize this discomfort. Cervical stenosis presents a special challenge when placing the catheter. In many patients, all that is required is the use of a tenaculum to place countertraction on the cervix. In more difficult cases, the catheter can be stiffened with the use of a guidewire.108 Fluid Choices
The most common fluid used for sonohysterography is sterile normal saline solution. Other solutions used with good results include lactated Ringer’s solution and 1.5% glycine solution. The type of fluid has no impact on pain. Procedure
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After voiding, the patient is placed in a dorsal lithotomy position and comprehensive baseline ultrasonography of the entire pelvis is performed. The ultrasound transducer is removed, a speculum is inserted into the vagina, and the cervix is cleansed with an antiseptic solution. A 20-mL syringe is filled with a sterile normal saline solution and connected to the clinician’s choice of a soft plastic catheter, which is primed with the saline solution to minimize injection of air bubbles that cause image artifact. The catheter is introduced through the cervix into the uterine cavity past the internal os. If the catheter tip touches the fundal endometrium, the patient will usually experience mild discomfort. Care must be used to remove the speculum without dislodging the catheter. This can be accomplished by gently grasping the catheter with a uterine packing forceps or ring forceps with the aid of an open-sided Graves speculum. A standard speculum can be used, but the uterine packing forceps must be inserted distal to the closed annular opening of the speculum, and the attached syringe must be small enough to fit through the speculum opening. Once the speculum is removed, the transvaginal transducer is replaced in the vagina. Alternatively, a transabdominal transducer can be used with the obligate loss of resolution. As the fluid is slowly injected, the uterus should be scanned in the longitudinal plane fanning from one cornu to the other and in the transverse plane from the top of the fundus to the cervix. Only 2 to 5 mL is required to distend the uterine cavity in most women. However, because of cervical leakage (especially when a balloon is not used), from 5 to 20 mL of fluid are actually used during the procedure. For this reason it is ideal to have a full 20- or 50-mL syringe filled with the selected fluid at the beginning of the procedure, with more in reserve. Inadequate distension may result in poor visualization, whereas overzealous distension may increase pain and obscure pathology.13,103 Selected views should be recorded as still images or on videotape for permanent records. The balloon, when used, should be deflated at completion of the evaluation and fluid aspirated
Figure 30-11
Mechanical shearing of endometrium.
before removal of the catheter to minimize subsequent uterine cramping. The patient should rest for 5 to 10 minutes to avoid postprocedure syncope. The entire procedure usually lasts 3 to 10 minutes. Common Problems
Common problems seen with this procedure include the following: ●
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air trapped in cavity. To prevent this, flush the catheter system before sonohysterography. mechanical shearing of endometrium. This is due to traumatic placement of the catheter. A sheared endometrial strip can cause a false-positive result (Fig. 30-11). balloon artifact. The balloon can interfere with visualization of the lower segment. Inflating the balloon with fluid instead of air will help avoid this. Regardless, the balloon should be deflated before the conclusion of the procedure to adequately assess the lower uterine segment and cervical canal for pathology.
SONOGRAPHIC FINDINGS Normal Findings in the Uterus and Ovaries Reproductive-Age Women
The uterus and ovaries of a reproductive-age woman are dynamic organs that undergo cyclic changes each month. Ultrasonography provides an information window to normal and abnormal
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Figure 30-12
Figure 30-13
Trilaminar appearance of the endometrial echo.
Cystic structure representing a dominant ovarian follicle.
physiologic changes, including synchrony between ovarian findings and normal endometrium.109,110 During menses, the endometrium is shed down to the basalis, which sonographically appears as a thin, linear echogenicity. The ovary during this phase of the cycle will often show evidence of numerous small sonolucencies suggestive of recruited preantral follicles. During the proliferative phase, estrogen stimulation causes the endometrium to appear as a triple layer, where the central echogenic line represents the uterine cavity, the outer lines represent the interface of the basal layer of the endometrium and the myometrium, and the relatively hypoechoic regions between these layers represent the functional layer of the endometrium (Fig. 30-12).111,112 A dominant follicle can be seen developing in the ovary as early as day 8 to 9 of the cycle. This simple cystic structure will exponentially grow to 20 to 25 mm in diameter and spontaneously rupture at the time of ovulation at around midcycle (Fig. 30-13).102,109 Free fluid in the cul-de-sac is highly suggestive that ovulation has occurred. During the postovulatory secretory phase, endometrial growth typically plateaus 5 days after the LH surge, reaching an
Figure 30-14 Corpus luteum cyst. A thick walled, irregular cystic structure containing internal echo that may correspond to blood and debris is consistent with a corpus luteum cyst.
average diameter of 14 mm. Progesterone exposure causes the previously hypoechogenic endometrium to transition to a homogeneous and echogenic pattern by the midluteal phase (see Fig. 30-8).111 These changes are related to the interface among luteal phase secretions, increased vascularity, and stromal edema.20 A corpus luteum will usually be visible in one of the ovaries during the secretory phase. It appears as a thick-walled, irregular structure sometimes containing internal echoes corresponding to blood and debris (Fig. 30-14). This finding can be difficult to differentiate from an endometrioma or neoplasm and often requires repeat scanning in the following follicular phase. Myometrial contractions that appear as waves in the endometrium can sometimes be seen with real-time ultrasonography. These contractions appear to progress from the cervix to the fundus in the late follicular phase and have been shown to increase in frequency and intensity around ovulation. In the luteal phase, these contractions are less pronounced. Some infertile women, especially those with endometriosis, appear to have hyperperistalsis and disorganized, nondirectional waves at midcycle.113–115 This has been hypothesized to result in sperm transport abnormalities and the spread of peritoneal endometriosis. The normal, nondistended fallopian tube is difficult to visualize sonographically due to its small diameter.116 On transverse views of the uterus, the origin of the fallopian tubes can sometimes be appreciated by following the invagination of the endometrium from the cornual region, which represents the tubal ostia, laterally into the adnexal region. Intraperitoneal fluid can sometimes enhance visualization of the fallopian tubes.117 Transvaginal ultrasound is a sensitive method of detecting the presence of free pelvic fluid; therefore, it is an important diagnostic tool in the assessment of pelvic pathology associated with increased peritoneal fluid.118 Free fluid is normally found in the female pelvis. The smallest amount consistently detected by transvaginal ultrasound is 8 mL. Typically 2 to 9 mL are found under normal physiologic circumstances. Pelvic ultrasonography depicts other pelvic structures, including loops of bowel and pelvic blood vessels. The internal iliac arteries are typically between 5 and 7 mm in transverse
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Section 5 Reproductive Imaging diameter and pulsate, whereas the iliac veins are larger (approximately 1 cm in diameter) but do not pulsate. Postmenopausal Woman
In contrast to normal reproductive-age women, postmenopausal woman not taking replacement hormones do not have cyclic changes in the reproductive organs. Transvaginal ultrasound measurement of endometrial thickness is routinely used to evaluate abnormal vaginal bleeding and has been used as a biomarker for estrogen exposure.59 The endometrium of hypoestrogenic women has a fine, thin linear echogenicity with an intact hypoechoic zone surrounding it, usually less than 5 mm thick. Increased estrogens, either exogenous (i.e., from hormone therapy) or endogenous (i.e., from obesity, diabetes, and hypertension), are associated with an increased endometrial thickness and risk of endometrial cancer. The postmenopausal ovary is more linear than ovoid and loses the appearance of cortical sonolucent areas consistent with preantral follicles. As a result, visualization is often difficult, particularly in postmenopausal women who have significant atrophy and narrowing of the introitus, precluding the use of the transvaginal probe. Some postmenopausal women will exhibit adnexal findings, and up to 3% will have unilocular ovarian cysts. Approximately 85% of simple ovarian cysts are epithelial in origin, and few ultimately prove to be malignant. Unilocular ovarian cysts less than 10 mm in diameter in asymptomatic postmenopausal women are unlikely to represent ovarian cancer, close to 50% spontaneously resolving within 60 days. In contrast, complex ovarian cysts with wall abnormalities or solid areas are associated with a significant risk for malignancy.119
Uterine Pathology Leiomyoma
Uterine fibroids, or leiomyomas, are the most common neoplasm of the female genital tract and are symptomatic in 15% to 25% of reproductive-age women. These tumors can cause abnormal bleeding and can cause pelvic pain, fertility, and pregnancy wastage. Ultrasound can localize fibroids as submucosal, intramural, or subserosal. Fibroids typically appear as well-circumscribed, hypoechoic masses that usually contain calcium or rarely fat and often undergo cystic degeneration and develop cystic or hemorrhagic areas. Small submucosal fibroids can cause focal hypoechoic indentation on the endometrial stripe. Pedunculated fibroids can be confused with solid adnexal masses, but identification of both ovaries separate from the mass can help establish a correct diagnosis. Doppler color ultrasound can usually identify a blood vessel that arises from the uterus to supply the myoma.30 Adenomyosis
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Adenomyosis is the presence of ectopic endometrial glands in the myometrium surrounded by hypertrophied smooth muscle. With careful examination, this condition can be detected in 8% to 30% of hysterectomy specimens. It typically affects the uterus in a diffuse manner, but focal disease can be present in the form of an adenomyoma. Ultrasound imaging can reveal diffuse uterine enlargement without focal abnormality, diffuse posterior myometrial thickening, or myometrial sonolucencies.121
Uterine Hypoplasia
Uterine hypoplasia is a disproportionately small uterine corpus, where the ratio of the uterine body to the cervix is reduced to less than the normal 2:1 ratio. Uterine hypoplasia before normal menopause can be due to drugs, pelvic irradiation, or premature ovarian failure. Müllerian Duct Anomalies
Müllerian duct anomalies represent a wide spectrum of abnormalities resulting from failure of development, fusion, or resorption of the paired müllerian ducts and occur in up to 5% of the general population. The most common of these anomalies are arcuate, septate, and bicornuate uteri.122 During ultrasonography, coronal imaging of the uterine fundal and endometrial contour is critical in differentiating a septum from a bicornuate uterus.123 A septum is diagnosed when a tissue band is seen separating two endometrial cavities in the absence of a fundal notch. A septum will usually appear as a hypoechoic band, because a septum is usually predominantly fibrous. A muscular septum will have the same echodensity as the myometrium. A bicornuate uterus is diagnosed when a tissue band, usually broader than a septum, is seen separating two diverging endometrial cavities in the presence of a fundal notch greater than 1 cm in depth. In many cases, refractive shadowing limits the ability of ultrasonography to distinguish between fibrous and myometrial tissue, and thus magnetic resonance imaging is the preferred modality for making the differential diagnosis between a septum and a bicornuate uterus.
Endometrial Abnormalities Endometrial pathology may include increased endometrial thickness, heterogeneity, cavitary lesions, and myometrial involvement. Patients with these findings usually need further investigation. Endometrial Thickness
The usefulness of endometrial thickness is predicated on visualization of a clear longitudinal stripe of endometrium. This may be reduced in cases of endometrial distortion due to uterine fibroids or abnormal uterine angulation. Endometrial Masses
Small lesions that project into the cavity, distortions of the uterine anatomy, and the phase of the menstrual cycle often pose challenges in precisely diagnosing endometrial pathology.7–9 Sonohysterography is essential for defining the location of the pathology where myomas typically originate from the myometrium, whereas polyps are contained within the endometrial cavity. Abdominal and transvaginal ultrasonography alone have limited usefulness in evaluating the exact location of endometrial cavity pathology.6 Intrauterine Adhesions
Intrauterine adhesions are suggested on ultrasonography by subtle alterations in the endometrial thickness and homogeneity and changes in the sharpness of the endometrial–myometrial interface.124 The instillation of fluid contrast into the endometrial cavity during sonohysterography provides an interface to greatly enhance the detection of these adhesions.
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Chapter 30 Pelvic Ultrasonography and Sonohysterography sonolucent fluid. The additional finding of low-level echoes can be a sign of chronic tubal salpingitis.
Early Pregnancy Ultrasound In early pregnancy, a blastocyst burrows into the decidualized endometrium and forms an amniotic cavity, a bilaminar embryonic disk, and the primary yolk sac.128 Proliferation of the trophoblast produces primary chorionic villi. Sonographically, the gestational sac is an echogenic ring surrounding a sonolucent center. It is the result of a trophoblastic decidual reaction that occurs as the primary villi invade maternal decidua. The yolk sac is visible sonographically at about 3 to 31⁄2 weeks postconception (5 to 51⁄2 weeks’ gestation), although it has been present since the blastocyst stage and implantation.129 It is fetal in origin, but extra-amniotic and about 4 mm in diameter. It appears as a thin and bright echogenic rim around a sonolucent center. It will remain for up to 10 weeks and eventually is incorporated beneath the amnion. It often precedes visualization of the embryo by 3 to 7 days and is reassuring until a fetal or embryonic pole with cardiac activity can be detected.130 Identification of fetal cardiac activity after 8 weeks’ gestation is associated with a pregnancy continuation rate of more than 95%.
Ectopic Pregnancy
Figure 30-15
Dermoid cyst. Solid cystic appearance.
Adnexal Pathology Ovaries
Sonography is invaluable for detecting ovarian pathology. A common finding is of polycystic ovaries. This is defined by the presence of 10 or more follicular cysts 2 to 8 mm in diameter on transabdominal ultrasound, increased stroma, and increased ovarian volume. Some investigators suggest that on transvaginal ultrasound the number of follicular cysts should be more than 15. The ovarian volume is usually greater than 10 cm3. Two of the most common benign complex masses are dermoid cysts (benign cystic teratomas) and endometriomas. Dermoid cysts can have many appearances that can range from completely cystic in appearance to a complex mass with hyperechoic solid elements (Fig. 30-15). These usually represent hair, fatty material, and occasionally teeth within the dermoid. Endometriomas are cystic ovarian structures that sonographically have a typical “ground glass” appearance characterized as homogeneous, low-level echoes in 90% of cases.64,125 Septations are seen in 29% of cases and fluid levels are present in 5%. These classic sonographic findings are not specific and can also be seen with hemorrhagic corpus luteum, ovarian abscess, dermoids, cystadenomas, and carcinomas.126,127 Tubes
Sonography can detect tubal dilation that appears as a fluidfilled spear-shaped or ovoid structure that usually contain only
Ectopic pregnancies comprise 2% of all pregnancies and are diagnosed most commonly with a combination of quantitative human chrorionic gonadotropin (hCG) measurements and transvaginal ultrasonography. Because ectopic pregnancies are the most common cause of pregnancy-related death in the first trimester, early management of this condition is essential to optimizing treatment and preserving fertility. The discriminatory zone is an important concept first described by Kadar and colleagues in 1981.131 The discriminatory zone represents the level of serum β-hCG at which an intrauterine gestational sac can be seen by ultrasonography. Using transvaginal ultrasonography, the discriminatory zone β-hCG level is generally accepted to be 2000 mIU/mL for a singleton pregnancy, although some clinicians use a β-hCG level as low as 1000 mIU/mL.132–135 It is important to remember that the discriminatory zone for an individual patient may be increased according to the type of sonographic equipment available, the experience of the ultrasound technologist, the presence of multiple intrauterine pregnancies, and pathology such as uterine leiomyomas, which may limit visualization of the gestational sac. However, when an intrauterine pregnancy cannot be definitely visualized by transvaginal ultrasonography with a β-hCG level greater than 2000 mIU/mL, an ectopic pregnancy should be suspected. The initial step in the evaluation of a patient at risk for ectopic pregnancy is to look for evidence of an intrauterine pregnancy. Although an intrauterine pregnancy does not absolutely exclude the possibility of an ectopic pregnancy, heterotopic pregnancies are rare. An exception is after application of ART, where heterotopic pregnancy is estimated to occur in 1% of subsequent pregnancies.136 An early intrauterine pregnancy is characterized sonographically as a gestational sac within the endometrial cavity, which is described as a hyperechoic trophoblastic decidual ring around the sonolucent chorionic cavity. An ectopic pregnancy can be
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Section 5 Reproductive Imaging associated with a pseudogestational sac on ultrasonography, which can be difficult to distinguish from a true intrauterine gestational sac. A pseudogestational sac is described as a fluid collection, usually irregular in shape, that is found close to the endometrial cavity line.137 A normal intrauterine gestational sac is visible on transvaginal ultrasonography approximately 32 to 36 days after an accurate last menstrual period, and the sac grows approximately 1 mm/day in mean diameter during early pregnancy.131,138 A yolk sac should be visible in most pregnancies when the gestational sac measures 8 mm, and definitely by 10 mm or approximately 5 weeks’ gestation. The embryo appears as a thickening along the edge of the yolk sac. The growth rate of the embryo is 1 mm/day, and fetal cardiac activity within the fetal pole can be detected with a gestational sac measurement of 18 mm or larger.139,140 Evaluation of the adnexa by transvaginal ultrasonography is of paramount importance in the patient with suspected ectopic pregnancy, especially in the absence of a visible intrauterine gestational sac (see Fig. 30-16). The most convincing finding of an ectopic pregnancy is a gestational sac in the adnexa, with or without a yolk sac or fetal pole. Approximately 85% of the time, the ectopic pregnancy will be found on the same side as the corpus luteum. The early sonographic appearance of the ectopic pregnancy is the presence of a hyperechoic trophoblastic “tubal” ring, with no myometrium around the gestation. If color flow Doppler ultrasonography is available, the increased blood supply around the trophoblastic ring can be demonstrated. The finding of fluid in the cul-de-sac in the absence of an intrauterine pregnancy increases the likelihood of an ectopic pregnancy.63 Ninety-five percent of ectopic pregnancies are located in the fallopian tube. A cornual (interstitial) pregnancy is diagnosed when a gestational sac is visualized sonographically more than 1 cm away from the most lateral aspect of the uterine cavity surrounded with a thin layer of myometrium.141 Rarely, a cervical pregnancy is diagnosed when a gestational sac in seen in the cervix but should not be confused with an intact gestational sac passing through the cervix. Ovarian and abdominal pregnancies are even rarer, and transvaginal ultrasonography is often essential in making these diagnoses.
CONCLUSION Ultrasonography and sonohysterography are well established as accurate imaging modalities for gynecologic lesions. These techniques are invaluable in the investigation of a range of gynecologic disorders, including abnormal uterine bleeding and infertility. As a screening tool, ultrasonography is useful in evaluating the uterus, fallopian tubes, and ovaries for symptomatic and asymptomatic pathology, including leiomyomas, ovarian cysts, and hydrosalpinges. Sonohysterography is particularly helpful in evaluating endometrial thickness and intrauterine lesions. Preoperatively, sonohysterography is an accurate way to determine the location and nature of lesions such as endometrial polyps and leiomyomas, and to assess the depth of endometrial carcinoma invasion. Sonohysterography can also be used to perform procedures, including
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Figure 30-16 Ectopic pregnancy. Typical hyperechoic trophoblastic “tubal” ring without myometrium around the gestation.
directed biopsies and tubal cannulation. Finally, ultrasonography can be used intraoperatively to guide hysteroscopic procedures and uterine curettage. Ultrasonography and sonohysterography are simple, safe, and inexpensive procedures that can add tremendously to diagnostic accuracy and should be considered as part of the complete assessment of the reproductive tract in many women.
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The uterus should be carefully assessed in both longitudinal and transverse axes for the presence of anomalies of the cervix and the uterus. Transvaginal ultrasound of the ovary should be reported giving the dimensions in three perpendicular planes. The endometrial echo has distinct characteristics that reflect the phase of the menstrual cycle. The gestational sac is seen as an echogenic ring surrounding a sonolucent center adjacent to the uterine cavity. All normal intrauterine gestational sacs should be visualized by 35 ± 2 days from the last menstrual period. The yolk sac appears at about 3 to 31⁄2 weeks postconception (5 to 51⁄2 weeks’ gestation). The pseudogestational sac can be confused with a true gestational sac and is usually described as a fluid collection centrally located within the uterine cavity. Sonohysterography is a sensitive diagnostic tool for investigating the presence of intrauterine pathology associated with abnormal uterine bleeding. In patients with infertility or recurrent pregnancy loss, sonohysterography is as sensitive as HSG for detecting lesions within the uterine cavity, with fewer false positives.
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47. Epstein E, Ramirez A, Skoog L, Valentin L: Transvaginal sonography, saline contrast and hysteroscopy for the investigation of women with postmenopausal bleeding and endometrium >5 mm. Ultrasound Obstet Gynecol 18:157–162, 2001. 48. Schwartz LB, Snyder J, Horan C, et al: The use of transvaginal ultrasound and saline infusion sonohysterography for the evaluation of asymptomatic postmenopausal breast cancer patients on tamoxifen. Ultrasound Obstet Gynecol 11:48–53, 1998. 49. Bissett D, Davis JA, George WD: Gynaecological monitoring during tamoxifen therapy. Lancet 344:1244, 1994. 50. Seoud M, Shamseddine A, Khalil A, et al: Tamoxifen and endometrial pathologies: A prospective study. Gynecol Oncol 75:15–19, 1999. 51. Achiron R, Lipitz S, Sivan E, et al: Changes mimicking endometrial neoplasia in postmenopausal, tamoxifen-treated women with breast cancer: A transvaginal Doppler study. Ultrasound Obstet Gynecol 6:116–120, 1995. 52. Bertelli G, Valenzano M, Costantini S, et al: Limited value of sonohysterography for endometrial screening in asymptomatic, postmenopausal patients treated with tamoxifen. Gynecol Oncol 78:275–277, 2000. 53. Bertelli G, Venturini M, Del Mastro L, et al: Tamoxifen and the endometrium: Findings of pelvic ultrasound examination and endometrial biopsy in asymptomatic breast cancer patients. Breast Cancer Res Treat 47:41–46, 1998. 54. Cecchini S, Ciatto S, Bonardi R, et al: Screening by ultrasonography for endometrial carcinoma in postmenopausal breast cancer patients under adjuvant tamoxifen. Gynecol Oncol 60:409–411, 1996. 55. Love CD, Muir BB, Scrimgeour JB, et al: Investigation of endometrial abnormalities in asymptomatic women treated with tamoxifen and an evaluation of the role of endometrial screening. J Clin Oncol 17:2050–2054, 1999. 56. American College of Obstetricians and Gynecologists: Tamoxifen and endometrial cancer. ACOG Committee Opinion 232. Washington, D.C., ACOG, 2000 57. Hann LE, Gretz EM, Bach AM, Francis SM: Sonohysterography for evaluation of the endometrium in women treated with tamoxifen. Am J Roentgenol 177:337–342, 2001. 58. Cohen MA, Sauer MV, Keltz M, Lindheim SR: Utilizing routine sonohysterography to detect intrauterine pathology before initiating hormone replacement therapy. Menopause 6:68–70, 1999. 59. Sit AS, Modugno F, Hill LM, et al: Transvaginal ultrasound measurement of endometrial thickness as a biomarker for estrogen exposure. Cancer Epidemiol Biomarkers Prev 12:1459–1465, 2004. 60. DeWaay DJ, Syrop CH, Nygaard IE, et al: Natural history of uterine polyps and leiomyomata. Obstet Gynecol 100:3–7, 2002. 61. Cohen MA, Seitzinger MR, Sauer MV, Lindheim SR: The value of sonohysterography in postmenopausal women prior to initiating hormone replacement therapy. NAMS (abstract), 1999. 62. Langer RD, Pierce JJ, O’Hanlan KA, et al: Transvaginal ultrasonography compared with endometrial biopsy for the detection of endometrial disease. NEJM 337:1792–1798, 1997. 63. Fleisher AC, Wheeler JE, Lindsay I, et al: An assessment of the value of ultrasonographic screening for endometrial disease in postmenopausal women without symptoms. Am J Obstet Gynecol 184:70–75, 2001. 64. Mais V, Guerriero S, Ajossa S, et al: The efficiency of transvaginal ultrasonography in the diagnosis of endometrioma. Fertil Steril 60:776–780, 1993. 65. Goldstein SR, Monteagudo A, Popiolek D, et al: Evaluation of endometrial polyps. Am J Obstet Gynecol 186:669–674, 2002. 66. Cowles TA, Magrina JF, Masterson BJ, et al: Comparison of clinical and surgical staging in patients with endometrial cancer. Obstet Gynecol 66:413–416, 1985. 67. Schink JC, Lurain JR, Wallemark CB, Chmiel JS: Tumor size in endometrial cancer: A prognostic factor for lymph node metastasis. Obstet Gynecol 70:216–219, 1987. 68. Valenzano M, Podesta M, Giannesi A, et al: The role of transvaginal ultrasound and sonohysterography in the diagnosis and staging of endometrial adenocarcinoma. Radiol Med 101:365–370, 2001.
69. Devore GR, Schwartz PE, Morris J: Hysterography: A 5-year followup in patients with endometrial carcinoma. Obstet Gynecol 60:369–372, 1982. 70. Alcazar JL, Errasti T, Zornoza A: Saline infusion sonohysterography in endometrial cancer: Assessment of malignant cells dissemination risk. Acta Obstet Gynecol Scand 79:321–322, 2000. 71. Shalev J, Meizner I, Bar-Hava I, et al: Predictive value of transvaginal sonography performed before routine diagnostic hysteroscopy for evaluation of infertility. Fertil Steril 73:412–417, 2000. 72. Kim AH, McKay H, Keltz MD, et al: Sonohysterographic screening before in vitro fertilization. Fertil Steril 69:841–844, 1998. 73. Pellerito JS, McCarthy SM, Doyle MB, et al: Diagnosis of uterine anomalies: Relative accuracy of MR imaging, endovaginal sonography, and hysterosalpingography. Radiology 183:795–800, 1992. 74. Soares SR, Barbosa dos Reis MM, Carnargos AF: Diagnostic accuracy of sonohysterography, transvaginal sonography, and hysterosalpingography in patients with uterine cavity diseases. Fertil Steril 73:406–411, 2000. 75. Sardanelli F, Renzetti P, Oddone M. Toma P: Uterus didelphys with blind hemivagina and ipsilateral renal agensis: MR findings before and after vaginal septum resection. Eur J Radiol 19:164–170, 1995. 76. Letterie GS, Haggerty M, Lindee G: A comparison of pelvic ultrasound and magnetic resonance imaging as diagnostic studies for müllerian tract abnormalities. Int J Fertil Menopausal Stud 40:34–38, 1995. 77. Reuter KL, Daly DC, Cohen SM: Septate versus bicornuate uteri: Errors in imaging diagnosis. Radiology 172:749–752, 1989. 78. Yoder IC: Diagnosis of uterine anomalies: Relative accuracy of MR imaging, endovaginal sonography, and hysterosalpingography. Radiology 185:343, 1992. 79. Keltz MD, Olive DL, Kim AH, Arici A: Sonohysterography for screening in recurrent pregnancy loss. Fertil Steril 67:670–674, 1997. 80. Raga F, Bonilla-Musoles F, Blanes J, Osborne NG: Congenital müllerian anomalies: Diagnostic accuracy of three-dimensional ultrasound. Fertil Steril 65:523–528, 1996. 81. Campbell S, Bourne TH, Tan SL, Collins WP: Hysterosalpingo-contrast sonography (HyCoSy) and its future role within the investigation of infertility in Europe. Ultrasound Obstet Gynecol 4:245–249, 1994. 82. Session DR, Lerner JP, Tchen CK, Kelly AC: Ultrasound-guided fallopian tube cannulation using Albunex. Fertil Steril 67:972–974, 1997. 83. Jeanty P, Besnard S, Arnold A, et al: Air-contrast sonohysterography as a first step assessment of tubal patency. J Ultrasound Med 19:519–527, 2000. 84. Spandorfer SD, Goldstein J, Navarro J, et al: Difficult embryo transfer has a negative impact on the outcome of in vitro fertilization. Fertil Steril 79:654–655, 2003. 85. Lindheim SR, Sauer MV: Upper genital-tract screening with hysterosonography in patients receiving donated oocytes. Intl J Gynecol Obstet 60:47–50, 1998. 86. Gonen Y, Casper FR, Jacobson W, Blankier J: Endometrial thickness and growth during ovarian stimulation: A possible predictor of implantation in in vitro fertilization. Fertil Steril 52:446–450, 1989. 87. Glissant A, de Mouzon J, Frydman R: Ultrasound study of the endometrium during in vitro fertilization cycles. Fertil Steril 44:786–790, 1985. 88. Fleisher AC, Herbert CM, Sacks JA, et al: Sonography of the endometrium during conception and nonconception cycles of in vitro fertilization cycles and embryo transfer. Fertil Steril 46:442–447, 1986. 89. Welker BG, Gembruch U, Diedrich K, et al: Transvaginal sonography of the endometrium during ovum pickup in stimulated cycles for in vitro fertilization cycles. J Ultrasound Med 8:549–553, 1989. 90. Dickey RP, Olar TT, Curole DN, et al: Endometrial pattern and thickness associated with pregnancy outcome after assisted reproduction technologies. Hum Reprod 7:418–421, 1992. 91. Krampl E, Feichtinger W: Endometrial thickness and patterns. Hum Reprod 8:1339, 1993. 92. Freidler S, Schenker JG, Herman A, Lewin A: The role of ultrasonography in the evaluation of endometrial receptivity following assisted
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reproductive treatment: A critical review. Hum Reprod Update 2:323–325, 1996. Coroleu B, Carreras O, Veiga A, et al: Embryo transfer under ultrasound guidance improves pregnancy rates after in vitro fertilization. Hum Reprod 15:616–620, 2000. Lindheim SR, Cohen M, Sauer MV: Operative ultrasonography for upper genital tract pathology. J Assist Reprod Genet 15:542–546, 1998. Lindheim SR, Morales AJ: Operative ultrasound using an echogenic loop snare for intrauterine pathology. J Am Assoc Gynecol Laparosc 10:107–110, 2003. Shalev E, Zuckerman H: Operative hysteroscopy under real-time ultrasonography. Am J Obstet Gynecol 153:1360–1361, 1986. Letterie GS, Kramer DJ: Intraoperative ultrasound guidance for intrauterine endoscopic surgery. Fertil Steril 62:654–656, 1994. Shalev E, Shimonoi Y, Peleg D: Ultrasound controlled hysteroscopy. J Am Coll Surg 179:70–71, 1994. Coccia ME, Becattini C, Bracco GI, et al: Pressure lavage under ultrasound guidance: A new approach for outpatient treatment of intrauterine adhesions. Fertil Steril 75:601–606, 2001. Kieler H, Ahlsten G, Haglund B, et al: Routine ultrasound screening in pregnancy and the children’s subsequent neurologic development. Obstet Gynecol 91:750–756, 1998. Bonnamy L, Marret H, Perrotin F, et al: Sonohysterography: A prospective survey of results and complications in 81 patients. Eur J Obstet Gynecol Reprod Biol 102:42–47, 2002. Yoshimitsu K, Nakamura G, Nakano H: Dating sonographic endometrial images in the normal ovulatory cycle. Int J Gynaecol Obstet 28:33–39, 1989. Lindheim SR, Morales AJ: Comparisons of sonohysterography to hysteroscopy: Lessons learned and avoiding pitfalls. J Am Assn Gynecol Laparosc 9:223–231, 2002. Adams J, Polson DW, Franks S: Prevalence of polycystic ovaries in women with anovulation and idiopathic hirsutism. BMJ 293:355–359, 1986. Hansen KR, Morris JL, Thyer AC, Soules MR: Reproductive aging and variability in the ovarian antral follicle count: Application in the clinical setting. Fertil Steril 80:577–583, 2003. Dessole S, Farina M, Capobianco G, et al: Determining the best catheter for sonohysterography. Fertil Steril 76:605–609, 2001. Keltz MD, Arici A, Duleba A, Olive DL: A technique for sonohysterographic evaluation of the endometrial cavity and tubal patency. J Gynecol Tech 1:213–216, 1995. Lindheim SR: Echosight Jansen-Anderson Coaxial catheter guided hysteroscopy. J Am Assn Gynecol Laparosc 8:307–311, 2001. Hackeloer B, Fleming R, Robinson H, et al: Correlation of ultrasonic and endocrinologic assessment of human follicular development. Am J Obstet Gynecol 135:122–128, 1979. Hall DA, Hann LE, Ferrucci JT, et al: Sonographic morphology of the normal menstrual cycle. Radiology 133:185–188, 1979. Fleicher AC, Kalemaris GC, Entman SS: Sonographic depiction of the endometrium during normal cycles. Ultrasound Med Biol 12:271–275, 1986. Sakamoto C: Sonographic criteria of phasic changes in human endometrial tissue. Int J Gynaecol Obstet 23:7–12, 1985. Abramowicz JS, Archer DF: Uterine endometrial peristalsis—a transvaginal ultrasound study. Fertil Steril 54:451–454, 1990. Kunz G, Beil D, Dioniger H, et al: The uterine peristaltic pump: Normal and impeded sperm transport within the female genital tract. Adv Exp Med Biol 424:267–277, 1997. Leyendecker G, Kunz G, Wilde L, et al: Uterine hyperperistalsis and dysperistalsis as dysfunctions of the mechanism of rapid sperm transport in patients with endometriosis and infertility. Hum Reprod 11:1542–1551, 1996. Farquhar CM, Rae T, Thomas DC, et al: Doppler ultrasound in the nonpregnant pelvis. J Ultrasound Med 8:451–457, 1989. Timor-Tritsch IE, Rottem S: Transvaginal ultrasonographic study of the fallopian tube. Obstet Gynecol 70:424–428, 1987.
118. Khalife S. Falcone T, Hemmings R, Cohen D: Diagnostic accuracy of transvaginal ultrasound in detecting free pelvic fluid. J Reprod Med 43:795–798, 1998. 119. Bailey CL, Ueland FR, Land GL, et al: The malignant potential of small cystic tumors in women over 50 years of age. Gynecol Oncol 69:3–7, 1998. 120. Sladkevicius P, Valentin L, Marsal K: Transvaginal Doppler examination of uteri with myomas. J Clin Ultrasound 24:135–140, 1996. 121. Reinhold C, McCarthy S, Brte PM, et al: Diffuse adenomyosis: Comparison of endovaginal ultrasound and MR imaging with histopathologic correlation. Radiology 199:151–158, 1996. 122. Collins JI, Woodward PJ: Radiological evaluation of infertility. Semin Ultrasound CT MR 16:304–316, 1995. 123. Cullinan JA, Fleischer AC, Kepple DM, Arnold AL: Sonohysterography: A technique for endometrial evaluation. Radiographics 15:501–514, 1995. 124. Fedele L, Bianchi S, Dorta M, Vignali M: Intrauterine adhesions: Detection with transvaginal ultrasound. Radiology 199:757–759, 1996. 125. Volpi E, DeGrandis T, Zuccaro G, et al: Role of transvaginal sonography in the detection of endometriomata. J Clin Ultrasound 23:163–165, 1995. 126. Kupfer MC, Schwimmer SR, Lebovic J: Transvaginal sonographic appearance of endometriomata: Spectrum of findings. J Ultrasound Med 11:129–132, 1992. 127. Dogan MM, Ugar M, Soysal SK, et al: Transvaginal sonographic diagnosis of ovarian endometrioma. Int J Gynecol Obstet 52:145–147, 1996. 128. Moore KL: Formation of the bilaminar embryo: The second week. In Moore KL (ed): The Developing Human: Clinically Oriented Embryology, 4th ed. Philadelphia, WB Saunders, 1988. 129. Sauerbrei E, Cooperberg PL, Poland JB: Ultrasound demonstration of the normal fetal yolk sac. J Clin Ultrasound 8:217–219, 1980. 130. Fine C, Cortier M, Doubilet P: Fetal heart rates: Values throughout gestation. J Ultrasound Med 7:S105, 1988. 131. Kadar N, DeVore G, Romero R: Discriminatory hCG zone. Its use in sonographic evaluation for ectopic pregnancy. Obstet Gynecol 58:156–161, 1981. 132. Barnhart KT, Katz I, Hummel A, Gracia CR: Presumed diagnosis of ectopic pregnancy. Obstet Gynecol 100:505–510, 2002. 133. Timor-Tritsch IE, Yeh MN, Peisner DB, et al: The use of transvaginal ultrasound in the diagnosis of ectopic pregnancy. Am J Obstet Gynecol 161:157–161, 1988. 134. Goldstein SR, Snyder JR, Watson C, Danon M: Very early pregnancy detection with endovaginal ultrasound. Obstet Gynecol 72:200–204, 1988. 135. Barnhart KT, Kamelle SA, Simhan H: Diagnostic accuracy of ultrasound, above and below the β-hCG discriminatory zone. Obstet Gynecol 94:583–587, 1999. 136. Tal J, Haddad S. Gordon N, Timor-Tritsch IE: Heterotopic pregnancy after ovulation induction and assisted reproductive technologies: A literature review from 1971 to 1993. Fertil Steril 66:1–12, 1006. 137. Turetsky DB, Alexander AA, Linden SS: Pseudogestational sac of ectopic pregnancy simulating intrauterine pregnancy with transvaginal sonography. J Clin Ultrasound 141:840–842, 1991. 138. Nyberg DA, Mack LA, Laing FC, Patten RM: Distinguishing normal from abnormal gestational sac growth in early pregnancy. J Ultrasound Med 6:23–27, 1988. 139. Schatz R, Jansen CAM, Wladimiroff JW: Embryonic heart activity: Appearance and development in early human pregnancy. BJOG 97:989–994, 1990. 140. Rempen A: Diagnosis of early pregnancy with vaginal sonography. J Ultrasound Med 9:711–716, 1990. 141. Lau S, Tulandi T: Conservative medical and surgical management of interstitial ectopic pregnancy. Fertil Steril 72:207–215, 1999.
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Magnetic Resonance Imaging Andrea B. Magen and Joseph C. Veniero
INTRODUCTION Magnetic resonance imaging (MRI) is increasingly used by gynecologists and especially reproductive surgeons to assess the genital tract in a variety of clinical situations that require precise detail of the reproductive organs. Sufficient detail is provided in most circumstances by transvaginal ultrasonography (TVUS) or saline infusion sonohysterogram. In some instances, such as in determining the size and location of fibroids or discerning adenomyosis, neither TVUS nor saline infusion sonohysterogram is definitive. Furthermore, accurate determination of a müllerian anomaly may allow more precise preoperative assessment and even potentially eliminate a surgical step, such as a diagnostic laparoscopy for resection of a uterine septum. Magnetic resonance imaging is gaining widespread acceptance and, in many instances, is a cost-effective tool in the evaluation of abnormal uterine bleeding. It is noninvasive, differentiates uterine anatomy in response to exogenous hormones or the normal menstrual cycle, and reliably localizes pelvic pathology and size of lesions. When uterine conservation is desired in women with fibroids, and TVUS or saline infusion sonohysterogram is indeterminate in localizing the depth of myometrial involvement of a fibroid, MRI should be considered as a part of the clinical algorithm. The precision of MRI localization of submucosal fibroids can obviate the need for hysterectomy and permit a skilled surgeon to hysteroscopically resect the fibroids. If the clinical examination is suspicious for adenomyosis and the TVUS is nondiagnostic, the clinician should strongly consider MRI. When the results of the imaging study would influence surgical route and planning, MRI should be considered in the preoperative evaluation. This chapter gives an overview of the physics of MRI and gives a visual overview of the potential clinical applications of this imaging modality.
PRINCIPLES OF MAGNETIC RESONANCE IMAGING Clinical MRI takes advantage of the physical properties of the protons in the body to produce anatomic images. All nuclei—in this case, hydrogen nuclei—have the physical properties of charge and spin. Depending on the charge and spin, certain atoms, including hydrogen nuclei (protons), behave as tiny magnets and have both polarity and an associated magnetic field with the properties of magnitude and direction. When placed in a magnetic field, they tend to align with the field in a lower energy state or against the field in a higher energy state.
When the system is at rest, in equilibrium, there are a relatively tiny number of excess protons in the lower energy state. These are the protons that are available for use in MRI. Because of the physical properties of the system, these magnetic fields do not remain perfectly aligned with the main magnetic field but rather they rotate or precess about the central axis of the main magnetic field, much as a spinning top precesses in the presence of gravity. This precession is very important in MRI because it is essentially the only parameter in the system that we can either change or measure. The Larmor equation tells us that the precessional frequency is equal to the strength of the magnetic field in which a particular proton of interest resides times a constant called the gyromagnetic ratio. The gyromagnetic ratio is fixed for a given nucleus. At the magnetic field strengths used in MRI, the precessional frequencies are in the radiofrequency range. If we know the strength of the magnetic field in a particular location, we can predict the precessional frequency of the protons in that location. Analogously, if we change the magnetic field in a predefined manner and if we can measure the precessional frequencies of various protons, we can calculate their positions as long as we know the magnetic field variations. Precessing protons will only absorb energy applied at their precessional frequency. When we introduce radiofrequency energy at the appropriate frequencies, the protons precessing at these frequencies absorb the energy and move to a higher energy state. As these protons relax back to equilibrium, radiofrequency signals can be detected at their particular precessional frequencies. In MRI, we use these principles to create images. During imaging, appropriate radiofrequency energy is put into the system while supplementary magnetic fields, called gradients, are added to or subtracted from the main magnetic field in a predefined linear fashion. Because the scanner can vary the gradients in all directions, the process of spacial localization, identifying the location of a particular signal in three-dimensional space, can be achieved. Multiple iterations of the imaging examination are performed and the scanner collects and reconstructs the obtained data, assigning the signal from the protons to the appropriate location on the image until the entire image is formed. Varying certain acquisition parameters, especially timing, changes the images so that their contrast varies depending more on their interactions with each other (T1-weighted imaging) or on their interactions with their local environment (T2-weighted imaging). Many other techniques and strategies are employed to vary the contrast, sensitivity, and efficiency of MRI and much more complete descriptions are available to the interested reader.1
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Figure 31-1 Normal anatomy. Axial (A,E), sagittal (B,C,F), and coronal (D) T2-weighted images. Normal structures including the cervix (c), vagina (v), endometrium (e), ovaries (o), plicae palmitae (pl), the anterior (a) and posterior (p) fornix, the cul-de-sac (s), rectum (r), urinary bladder (b), and urethra (ur), are visible. The myometrium (m), endometrium (e), and junctional zone (jz), as well as nabothian cysts (arrow) are also identified. Also visible are the external cervical os (os), junctional zone (jz), lateral fornices (lf), and coccyx (cc). continued
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MRI has many advantages over ultrasound and computed tomography (CT) for the evaluation of pelvic anatomy, congenital anomalies, and pathologic disorders. Ultrasound, the workhorse of pelvic imaging, is considered convenient, efficient, and cost-effective. Ultrasound is easily accessed by gynecologists for evaluation of their patients and is an ideal screening examination. Among its many uses are the identification and followup of cysts, endometrial abnormalities, and fibroids. However, even in the best of hands, ultrasound remains operator-dependent and patient limited. Pelvic CT, performed in the axial plane, is limited by surrounding osseous structures and by the soft tissue contrast produced by differential absorption of the X-ray beam. The patient is exposed to ionizing radiation and likely to an intravenous contrast medium to exploit variations in tissue blood supply. MRI is also useful in the identification and differentiation of simple, proteinaceous, or hemorrhagic fluid as well as in the identification of fluid septations and loculations. The strengths of MRI include sensitivity to soft-tissue contrast unparalleled in other imaging modalities, multiplanar capability, less limitation by uterine and in most cases patient size (especially relative to ultrasound), and the lack of ionizing radiation. With recent advances in sequence and hardware technology, the classic MRI limitation of sensitivity to motion, whether it derives from patient respiration or peristalsis, is decreasing.
The following sections include illustrative cases of normal anatomy and benign pathology frequently encountered by reproductive surgeons. The focus is on congenital and acquired pathology, but we do not discuss differentiation of a benign or malignant cyst. The assessment of malignant versus benign cysts is most commonly determined by ultrasonography (see Chapter 30).
NORMAL ANATOMY The normal uterus, cervix, vagina, endometrium, and ovaries can be readily identified on T2-weighted images in a variety of planes. Also the plicae palmitae, the anterior and posterior fornix, the cul-de-sac, rectum, urinary bladder, and urethra are easily identified (Fig. 31-1). The uterine MRI anatomy can be subdivided. The signal intensity and thickness of these layers can vary based on the hormonal milieu. The myometrium is seen externally and tends to be intermediate in signal intensity. Centrally is the endometrium, which tends to be of increased signal on T2-weighted sequences. Between the two layers is a much darker, uniform layer, called the junctional zone. Although histologically similar to the adjacent myometrium, the difference in signal intensity is believed to result from a lower water content relative to the adjacent myometrium3 and the compact longitudinally oriented smooth muscle bundles oriented parallel to the endometrium4 (see Fig. 31-1). The radiologist, when assessing the uterus for pathology, evaluates the thickness, signal characteristics, and distinctness of each of these zones.
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Figure 31-3 Arcuate uterus. Oblique axial T2-weighted image demonstrating the contour bulge (b) at the fundus without external fundal contour deformity.
Figure 31-2 Vaginal and uterine agenesis. Sagittal T2-weighted image of a patient with vaginal and uterine atresia. Bladder (b) and rectum (r) are identified; uterus, cervix, and vagina are absent.
CONGENITAL ANOMALIES OF THE REPRODUCTIVE TRACT
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The MRI appearance of müllerian anomalies directly corresponds to the findings on both hysterosalpingography and gross examination. Several potential anatomic observations can be made. In cases of uterine agenesis, no vaginal or uterine tissue is present (Fig. 31-2). The arcuate uterus is a frequent müllerian anomaly that usually has little clinical significance and is identified as a contour or “bulge” of the fundus, with no changes associated with the endometrial canal (Fig. 31-3). Several anomalies are easily determined by MRI, such as a unicornuate uterus where a single horn can be identified (Fig. 31-4). However, others are more difficult, especially when the decision of whether to proceed to surgery relies on the MRI diagnosis. The most frequent differential diagnosis that a radiologist is asked to make on MRI is between a septate and bicornuate uterus. In a septate uterus, the septum can be seen extending from the fundus to any level in the uterine cavity up to the internal os. MRI can distinguish between a muscular and a fibrous septum based on the signal characteristics. A fibrous septum is
Figure 31-4 Unicornuate uterus. Axial T2-weighted image of a unicornuate uterus demonstrating a solitary uterine horn (u); urinary bladder (b).
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Chapter 31 Magnetic Resonance Imaging of low signal on T2-weighted sequences, whereas the signal of a muscular septum will follow that of the myometrium, if obtained in the correct plane (Figs. 31-5 to 31-9). The basic concept holds that a bicornuate uterus would have a muscular septum and a septate uterus would be more fibrous. A septate uterus will have some “dimpling” of the fundus of the uterus, but the external surface of the uterus does not form two horns. In a
bicornuate uterus the two horns are identified and the external fundal surface is clearly divided (Figs. 31-10 and 31-11). In a uterus didelphys the separate canals and cervices are easily identified. In cases where there is a vaginal septum, it is also easily identified (Fig. 31-12). In patients who present at puberty with acute pain and amenorrhea, the differential diagnosis should include an intact
Figure 31-5 Septate uterus. Coronal T2-weighted image through the uterus demonstrating a myometrial septum (ms) in the fundus and the fibrous portion of the septum (fs) extending to the cervix (c). Note the fundal contour deformation (fd) accentuated by the urinary bladder.
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Figure 31-6 Septate uterus. A, In this case, the axial T2-weighted image shows that the muscular septum (s) has the same signal as the myometrium and extends nearly the entire length of the canal; cervix (c), fundus (f), junctional zone (jz). B, Coronal image through the uterine body; myometrium (m), endometrium (e), and bladder (b). C, A coronal T2-weighted image through the abdomen in a patient with a septate uterus demonstrates a solitary kidney (k). The liver (l) and spleen (spl) are also seen.
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B Figure 31-8 Septate uterus. The uterus of this patient, best seen on reconstructed oblique axial T2-weighted images (A,B), has a dark fibrous septum (fs) that extends into the cervix (c).
B Figure 31-7 Septate uterus. A, In this case, the oblique coronal T2-weighted images demonstrate the shallow fundal deformity (fd) and the thick muscular septum (s) that extends to the lower uterine segment. B, The oblique axial T2-weighted image demonstrates the muscular septum (s) and the endometrial canals (e). The bladder (b) and normal ovary (o) are included on these images.
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Figure 31-9 Septate uterus. This is best appreciated on oblique coronal T2-weighted image through the uterine canal demonstrating myometrial septum (ms).
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Figure 31-10 Bicornuate uterus with atretic right horn (ah). T2-weighted images in the axial (A) and coronal (B) planes show a normal-appearing left horn (h) and an atretic horn, which lacks the signal characteristics of endometrium and junctional zone.
hymen, vaginal septum, and congenital absence of the cervix. In these cases, blood products of varying ages may be identified in the vaginal canal or uterus. Blood products range from bright through the spectrum of grey to dark. The darkest grey (almost black) represents hemosiderin (Fig. 31-13).
ACQUIRED ANOMALIES OF THE REPRODUCTIVE TRACT The most common acquired anomalies of the reproductive tract that may require radiologic help to decide on appropriate treatment are leiomyomas and adenomyosis.
Adenomyosis
Figure 31-11 Bicornuate uterus. Coronal image through the plane of the uterus demonstrating the large gap between the two uterine horns (h), which join at the lower uterine segment (lus), and the single cervix (c).
The diffuse or localized forms of adenomyosis can be accurately detected with MRI. In diffuse adenomyosis, the thickness and signal characteristics of the junctional zone are evaluated. If the junctional zone is greater than 10 to 12 mm thick, adenomyosis has been shown to be present. Rarely, uterine contractions5 have been shown to produce segmental thickening of the junctional zone, hence the reliance on these values. In adenomyosis, the junctional zone may contain regions of bright or high signal intensity on the T1- or T2-weighted images, corresponding to regions of hemorrhage6 (Figs. 31-14 to 31-17). Text continued on p. 472
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B Figure 31-12 Uterus didelphys. Series of contiguous axial images (A–C) with two uterine canals and cervices.
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Figure 31-13 Uterus didelphys with obstructive hymen and atretic right uterus (r). A, Axial T1-weighted high-signal material in dilated cervical canal (c); B, through a lower level. C and D, Axial T2–weighted images at the same level as A and B, with sagittal (E) and coronal (F,G) images through dilated cervix and vagina with blood central and along the periphery (as in B and D). G also includes each uterus, left (l) and right (r). The signal of the blood in the cervical canal and vagina varies depending on the age and oxygenation of the blood products (see text). continued
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F Figure 31-13 cont’d Uterus didelphys with obstructive hymen and atretic right uterus (r). (E) Sagittal and coronal (F,G) images through dilated cervix and vagina with blood central and along the periphery (as in B and D). G also includes each uterus, left (l) and right (r). The signal of the blood in the cervical canal and vagina varies depending on the age and oxygenation of the blood products (see text).
G
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A B
C
D
E
F
Figure 31-14 Adenomyosis. Sagittal (A,B) and coronal (C) transvaginal ultrasound demonstrates a heterogeneous focal region felt at the time to represent a fibroid. Axial T1-weighted (D), axial T2–weighted (E), and coronal (F) images from an MRI performed on the same patient show the changes of adenomyosis, a region of decreased signal in T2 containing punctate foci of high signal on T1-weighted and T2-weighted sequences, corresponding to blood degradation products. Note in the affected area the loss of a well-defined junctional zone.
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B Figure 31-15 Adenomyosis. A, Axial T2 -weighted and B, T1-weighted images through focal adenomyosis with loss of junctional zone and foci of high signal on both sequences.
A
A focal adenomyoma may appear as mass with heterogeneous to low signal intensity, with an appearance that may be similar to a leiomyoma. However, the margins should be less distinct, corresponding to the interdigitation of the adenomyoma with the myometrium (see Fig. 31-15).
defect that corresponds to the surgical site can be identified on MRI (Fig. 31-20). However, there are no good data on the correlation between the scar characteristics and potential future reproductive outcomes.
Cervical Anomalies Leiomyoma These benign tumors have a characteristic appearance on T2-weighted images. The margins are distinct from the surrounding myometrium, and the signal intensity is less than the surrounding myometrium, approaching that of the junctional zone. The degenerated myomas contain blood, blood degradation products, mucin, or hyaline and will have a heterogeneous appearance. Although MRI can distinguish these more complex myomata from the “typical” myoma, it cannot distinguish which of these substances are present. MRI has also proven useful in distinguishing fibroids from other solid pelvic masses and for localization, which may affect therapy7 (Figs. 31-18 and 31-19). However, there are no clear criteria that can distinguish malignant from benign lesions.
Post-Cesarean Section Defects
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The high frequency of cesarean sections and potential dehiscence or rupture at the scar site has led to some interesting although clinically obscure observations on MRI. The scar or myometrial
The anatomy of the cervix has similar components as the uterus. The benign abnormality identified is nabothian cysts. Because nabothian cysts contain fluid, they follow fluid on the T2-weighted sequences and are sharply contrasted from the surrounding stroma (Fig. 31-21).
OVARY Normal ovaries are typically identified by the follicles and cysts (Fig. 31-22; see also Fig. 31-1). A major indication for MRI is often to distinguish a persistent physiologic cyst from a pathologic one. Hemorrhagic cysts are identified by high signal on a T1-weighted sequences without loss of signal on fatsuppressed sequences. This indicates blood or proteinaceous material within the cyst lumen (Fig. 31-23). Dermoid cysts are identified mainly by the fat component, with a sequence that will have fat as high signal intensity (bright) and a sequence that suppresses the fat signal (dark) lesion (Fig. 31-24). Text continued on p. 478
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A
B
C
D
Figure 31-16 Diffuse adenomyosis. Adenomyosis involves the majority of the uterus; axial T1-weighted (A), axial T2-weighted (B), sagittal T2-weighted (C), and coronal T2-weighted (D) images with loss of the junctional zone in the affected region. Foci of high signal on both T1-weighted and T2-weighted sequences represent blood products.
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B
A Figure 31-17 Diffuse adenomyosis. Sagittal T2-weighted (A) and axial T2-weighted (B) images show complete involvement of the uterus with adenomyosis. C, The axial T1-weighted image shows small foci of high signal.
C
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A
B
Figure 31-18 Fibroids. T2-weighted sagittal (A) and axial (B) images of multiple uterine fibroids of low signal relative to the myometrium throughout the uterus in multiple locations, including submucosal (sm), myometrial (m), and exophytic (exo).
A Figure 31-19 Fibroids. T2-weighted sagittal (A) and coronal (B) images of myometrial fibroid (f) with internal degeneration, represented by internal areas of high signal.
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Section 5 Reproductive Imaging Figure 31-20 Cesarean section defect. The T2-weighted sagittal image shows the contour deformity (arrow) in the lower uterine segment.
A 476
Figure 31-21 Nabothian cysts. T2-weighted coronal (A) and sagittal (B) images of the uterus, showing a cluster of small cysts aligned along the endocervical canal (arrow).
B
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Figure 31-22 Ovary. Normal physiologic follicle (p) in right ovary on axial T2-weighted image through the pelvis.
A
B
Figure 31-23 Blood products in an ovarian cyst. In a right ovarian cystic lesion (o) there is homeogeneous high signal on the axial T1–weighted (upper) image. On the T2-weighted (lower) image there is a gradient of progressive signal loss called shading. This represents a gradient of blood degradation products, as can be seen in endometriomas or more chronic hemorrhagic ovarian cysts.
C Figure 31-24 Dermoid tumor. Axial images through the pelvis show a left adnexal mass that is high signal on T1-weighted (A) and T2-weighted (C) images in a frondlike low signal central region (arrow). The high signal component loses signal on B, a T1–weighted, fat-saturated sequence. The loss of signal on the fat saturation signal corresponds to fat. These characteristics are diagnostic for a dermoid tumor.
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A
B Figure 31-25 Endometriosis. A, T1–weighted and B, T2-weighted sagittal sequence showing a soft-tissue signal mass (m) in the cul-desac that contains small foci of high signal on both sequences. C, T1-weighted image after IV gadolinium shows enhancement through this tissue.
C
478
Endometriosis cysts can be identified by the cyst contents, which will include blood or proteinaceous fluid of varying ages. Typically, there is a peripheral dark signal, indicating hemosiderin. There may be a relatively large amount of associated soft tissue, which would represent the associated inflammatory response or adhesions. Although MRI may identify endometriomas as small as 5 mm, it cannot identify the sheetlike peritoneal involvement (Figs. 31-25 and 31-26). In peritoneal inclusion cysts, typically the ovary is not visualized within the fluid. The pelvic fluid will appear as a loculated collection (Fig. 31-27). Potential malignancies can
be identified on MRI by similar criteria as those used in ultrasonography.
URETHRA Chronic pelvic pain may have any of a large number of potential causes. MRI may help in identifying the cause; this imaging modality is often ordered to evaluate for adenomyosis or endometriomas as a cause of chronic pain. However, occasionally a urethral diverticulum is observed that some believe may contribute to the pain syndrome.
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A
B Figure 31-26 Endometrioma. A, Axial T1-weighted image through the pelvis demonstrating high signal collection (r) in the right adnexa and in the left adnexa, two locules: a medial locule (ml) and lateral locule (ll). B, fat-saturated T1-weighted image shows no change in the signal characteristics of the collections. The medial locule has high signal and the lateral locule is of low signal This excludes extracellular fat producing the high signal in (r) and (ml). C, T2-weighted axial image at the same level. The signal characteristics change based on the age of the blood degradation products (see text).
C
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A
B Figure 31-27 Peritoneal inclusion cysts. A, Axial and B, multiple sagittal T2-weighted images show pelvic fluid collection in the cul-de-sac (cds) containing multiple septations. continued
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C Figure 31-27 cont’d C, axial T1-weighted, fat-saturated sequence before and after IV gadolinium shows enhancement in the septae (sep) and uterus (u) but no enhancement in the fluid.
A urethral diverticulum is identified as a fluid collection adjacent to the urethra (Fig. 31-28). At times, the neck of the diverticulum can be identified. On occasion, complex fluid (typically proteinaceous) is identified. Only the wall of the diverticulum should enhance, without any nodularity, which would be concerning for a neoplastic process.
●
●
●
PEARLS ●
MRI is an excellent modality for imaging the pelvic organs when ultrasonography is not adequate or definitive.
MRI is especially good for characterizing congenital anomalies of the reproductive tract. In patients who present at puberty with acute pain and amenorrhea, MRI is helpful in the differential diagnosis of an intact hymen, vaginal septum, or congenital absence of the cervix. MRI is more accurate than ultrasonography for the diagnosis of adenomyosis.
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Section 5 Reproductive Imaging Figure 31-28 Urethral diverticulum. A, Periurethral fluid collection (arrow) extending from 12 to 6 o’clock position on axial T1-weighted sequence; the contents have low signal. B, T1-weighted fat-saturated sequence after IV gadolinium with peripheral enhancement and C, T2-weighted sequence; the contents have high signal. These signal characteristics indicate that the diverticulum contains fluid (not blood or proteinaceous material). No nodule is within the fluid.
A
B
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Chapter 31 Magnetic Resonance Imaging REFERENCES 1. Mitchell DG, Schonholz L, Hilpert PL, et al: Zones of the uterus: Discrepancy between US and MR images. Radiology 174:827–831, 1990. 2. McCarthy S, Tauber C, Gore J: Female pelvic anatomy: MR assessment of variations during the menstrual cycle and with the use of oral contraceptives. Radiology 160:119–123, 1986. 3. McCarthy S, Scott G, Majumdai S, et al: Uterine junctional zone: MR study of water content and relaxation properties. Radiology 171:241–243, 1989. 4. Brown HK, Stoll BS, Nicosia SV, et al: Uterine junctional zone: Correlation between histologic findings and MR imaging. Radiology 179:409–413, 1991.
5. Kang S, Turner DA, Foster GC, et al: Adenomyosis: Specificity of 5 mm as the maximum normal uterine junctional zone thickness in MR images. Am J Roentgenology 34:1157–1182, 1996. 6. Togashi K, Nishimura K, Itoh K, et al: Adenomyosis: Diagnosis with MR imaging. Radiology 166:111–114, 1988. 7. Weinreb JC, Barkoff ND, Megibow A, Demopoulos R: The value of MR imaging in distinguishing leiomyomas from other solid pelvis masses when sonography is indeterminate. Am J Roentgenology 154:295–299, 1990.
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32
Fertility Preservation in Cancer Patients Mohamed A Bedaiwy, Tommaso Falcone, Jeffrey M. Goldberg, Marjan Attaran, and Ashok Agarwal
INTRODUCTION In the modern era of aggressive treatment of malignancies, many cancer survivors will be of reproductive age and wish to resume normal lives. Consequently, fertility preservation has become an increasingly important issue. In addition to the expected difficulties with fertility, obstetrics disorders, such as early pregnancy loss, premature labor, and low birth weight, have also been described after cancer treatment.1 Fertility preservation strategies have been designed in an effort to protect or regain reproductive function in patients exposed to chemotherapy and radiotherapy, whether treatment be for malignancies or other systemic diseases, such as lupus. Advances in assisted reproductive technologies (ART), including ovarian tissue cryopreservation and transplantation, oocyte cryopreservation, and novel ovulation induction approaches, offer new hope to women at risk of being rendered sterile by their treatments. The following chapter reviews the pathophysiology of chemotherapy/radiotherapy-induced gonadal toxicity and indications and outcomes of techniques used for fertility preservation.
PATIENT POPULATION The target population is comprised of female and male cancer patients who wish to retain future fertility. Childhood cancer is relatively uncommon, affecting only about 14 of every 100,000 children in the United States each year, and almost 80% of these children survive to adulthood. The most common childhood malignancies are acute lymphoblastic leukemia, central nervous system tumors, and lymphomas. During adolescence, the incidence of osteosarcoma also increases. In the early 20s, the risk of sarcomas and embryonic cancers increases as well.1 In adults, the leading cancers are lung, colon and rectum, and breast, the latter of which is the most common cancer in women. Gynecologic malignancies, lymphomas (including Hodgkin’s disease), melanomas, and bladder cancers are also relatively common. The mainstay of treatment of all of these malignancies remains surgery, chemotherapy, and radiation. Premature gonadal failure is a well-known consequence of ovarian exposure to chemotherapeutic drugs. A wide variety of malignant and nonmalignant conditions during the reproductive years are treated with gonadotoxic chemotherapy. Although there are several reports of girls under age 16 who have requested preservation of fertility before cancer therapy, the most common malignancy in reproductive-age women that requires immediate fertility intervention is breast cancer.2,3 Fifteen percent of all
breast cancer cases are estimated to occur in women younger than age 40.4 Premature gonadal failure is also a well-known consequence of ovarian exposure to radiation. In general, radiotherapy is used cautiously in children and adolescents because of its late sequelae on immature and developing tissues.1 Pelvic radiotherapy is most commonly used to provide local disease control for solid tumors, including tumors of the bladder, rectum, uterus, cervix, and vagina, all of which are more common in adult women. Cervical cancer is perhaps the most common malignancy in reproductive-age women desiring fertility-preserving intervention. It is estimated that 50% of the 13,000 women newly diagnosed with cervical cancer in the United States will be younger than age 35.5
CHEMOTHERAPY AND OVARIAN DAMAGE The extent of chemotherapy-induced gonadotoxicity is variable. Histologic sections of the ovary following treatment with cytotoxic drugs known to cause ovarian failure show a spectrum of changes ranging from decreased numbers of follicles to absent follicles to fibrosis. The exact incidence of premature ovarian failure following chemotherapy is difficult to establish because many factors contribute to ovarian toxicity.
Cytotoxic Drug Targets Cytotoxic drugs can destroy maturing follicles, impair follicular maturation, deplete primordial follicles, or produce some combination of these effects. Destruction of maturing follicles results in temporary amenorrhea, whereas destruction of primordial follicles results in permanent amenorrhea secondary to ovarian failure. The primary target of individual cytotoxic drugs is believed to be either granulosa cells or oocytes. It is difficult to determine exactly which target is primary because the structural and functional relationship between granulosa cells and oocytes is so close that destruction of either cell type leads to demise of the other. The menstrual dysfunction that occurs during chemotherapy is not always due to the direct toxic effects on the ovary. Severe illness, malnutrition, and general mental and physical stress can interfere with normal function of the hypothalamic-pituitaryovarian axis. Short-term disruption of a menstrual cycle can also be the result of destruction of growing follicles rather than primordial follicles. Destruction of all growing follicles will delay
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Section 6 Infertility and Recurrent Pregnancy Loss menses for at least 3 months, because it takes a primordial follicle approximately 85 days to reach the stage of ovulation.
Risk Factors for Gonadal Damage The most important risk factors for gonadal damage are the age of the patient, the drug class, and cumulative dose of the drug. The risk of gonadal damage increases with the age of the woman. This is most likely due to the presence of fewer remaining oocytes compared to younger patients. In one study of women who had received mechlorethamine, Oncovin (vincristine), procarbazine, and prednisone (MOPP protocol) for Hodgkin’s disease, the subsequent amenorrhea rate was 20% for women younger than age 25, compared to 45% for those at least 25 years old.6 In another study, the overall incidence of premature ovarian failure after MOPP chemotherapy was 61%.7 Cytotoxic chemotherapeutic agents are not equally gonadotoxic. Cell-cycle nonspecific chemotherapeutic agents are considered to be more gonadotoxic than cell-cycle specific ones (Table 32-1). Alkylating agents are among the most gonadotoxic of these cell-cycle nonspecific drugs, and women who have received high-dose alkylating agent therapy are at highest risk for premature ovarian failure. Cyclophosphamide is considered to be the most gonadotoxic member of this category.
Predicting Ovarian Failure Premature ovarian failure does not consistently occur in patients receiving multiagent chemotherapy, regardless of age or type of chemotherapeutic agent. Most young patients with Hodgkin’s disease treated with multiagent chemotherapy and radiation to
a field that does not include the ovaries will be fertile, although their fertility will begin to decrease at a younger age than matched controls.8 A spontaneous conception was reported in a young woman with premature ovarian failure after 14 courses of an alkylating agent combined with pelvic irradiation for treatment of Ewing’s sarcoma of the pelvis.9 This exemplifies the difficulties in predicting the probability of ovarian failure after chemotherapy, which also makes it difficult to evaluate the efficacy of treatment aimed at preserving ovarian function.
Markers for Gonadal Damage Serum Markers
Inhibin B, antimüllerian hormone, and follicle-stimulating hormone (FSH) levels have been used as markers for ovarian function after chemotherapy, although none are ideal. Inhibin B and antimüllerian hormone are produced by the granulosa cells, and FSH release from the pituitary is inhibited by estradiol and inhibin B. Elevation of serum FSH levels and decreased inhibin B and antimüllerian hormone reflect decreased ovarian reserve in cancer survivors, even in the presence of regular menses. Cancer chemotherapy is associated with a transient suppression of inhibin B in prepubertal girls. Consequently, inhibin B levels, together with sensitive measurements of FSH, are potential markers of the gonadotoxic effects of cancer chemotherapy in prepubertal girls.10 Ultrasonographic Markers
Another method to assess ovarian reserve in these patients is ultrasonographic determination of ovarian volume and antral follicle count.11 Cancer survivors with normal ovarian function tend to have normal antral follicle counts, although their ovarian volumes are often smaller than controls.
Table 32-1 Gonadotoxic Chemotherapeutic Agents* High toxicity Alkylating agents (cell-cycle phase nonspecific) Nitrogen mustards Cyclophosphamide Melphalan Chlorambucil Mechlorethamine Nitrosoureas Carmustine Lomustine Alkyl sulfonates Busulfan Methylhydrazine derivative (cell-cycle phase nonspecific) Procarbazine Intermediate toxicity Platinum coordination complexes (cell-cycle phase nonspecific) Cisplatin Carboplatin Antibiotics (cell-cycle phase nonspecific) Doxorubicin Low risk Folic acid analogs (cell-cycle phase specific) Methotrexate Pyrimidine analogs (cell-cycle phase specific) Fluorouracil Antibiotics (cell-cycle phase nonspecific) Bleomycin Dactinomycin Vinca alkaloids (cell-cycle phase specific) Vincristine Vinblastine
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*Female gonads; male gonads may have different sensitivity. Many drugs have unknown risks.
RADIOTHERAPY AND DAMAGE TO PELVIC ORGANS Pelvic radiotherapy damages both the ovaries and the uterus. Ovarian damage from radiotherapy results in impaired fertility and premature ovarian failure.11–19 Radiation therapy–induced uterine damage manifests as impaired growth and blood flow.20 The effects on subsequent pregnancies can be substantial.
Ovarian Damage The ovarian follicles are remarkably vulnerable to DNA damage from ionizing radiation. Radiation therapy results in ovarian atrophy and reduced follicle stores.18 As a result, serum FSH and luteinizing hormone (LH) levels progressively rise and estradiol levels decline within 4 to 8 weeks after radiation exposure. On the cellular level, irradiation of oocytes results in rapid onset of pyknosis, chromosome condensation, disruption of the nuclear envelope, and cytoplasmic vacuolization. The irreversibility of this damage has been attributed to the lack of germline stem cells in the ovary. However, a recent study suggested the presence of germline stem cells in the adult ovary.19 If these findings are confirmed by others, they leave open the possibility that new oocytes might be able to be regenerated after depletion by chemotherapy or radiotherapy.
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Chapter 32 Fertility Preservation in Cancer Patients Table 32-2 Determinants of Radiation-induced Gonadal Failure Age of patient Cumulative dose to the ovary Direct or scatter radiation Concomitant chemotherapy
Risk Factors for Ovarian Damage
Cancer patients are at high risk for premature ovarian failure after treatment with pelvic or total body radiation. The degree of ovarian damage is related to the patient’s age and the total dose of radiation to the ovaries (Table 32-2). For example it may take 12 Gray (Gy; 1 rad = 1 cGy) to induce permanent ovarian failure in prepubertal girls and only 2 Gray to achieve the same result in women older than age 45.12 It is generally estimated that a single dose of 6.5 to 8.0 Gy will cause permanent ovarian failure in most postpubertal women.13 A dose-dependent reduction in the primordial follicle pool occurs when exposing ovaries to radiotherapy. It is estimated that as little as 3 Gy is enough to destroy 50% of the oocyte population in young reproductive-age women.14 The dose-response of the ovaries to irradiation has been demonstrated in several studies.15–17 When the mean radiation dose to the ovary was 1.2 Gy, 90% of patients retained their ovarian function. When the mean dose was 5.2 Gy, only 60% retained ovarian function. Ovarian failure will occur in virtually all patients exposed to pelvic radiation at doses necessary to treat cervical cancer (85 Gy) or rectal cancer (45 Gy) or to total body radiation for bone marrow transplantation (8 to 12 Gy to the ovaries). The addition of chemotherapy to radiotherapy further decreases the dose required to induce premature ovarian failure. Even if the ovaries are not directly in the radiation field, radiation scatter can reduce ovarian function. When periaortic lymph node irradiation for treatment of Hodgkin’s disease exposes the ovaries to approximately 1.5 Gy, the short-term functioning of the ovaries is not affected. The effect of this dose on longterm function remains uncertain. It is important to discuss with the radiotherapist the expected dose that will be delivered to the ovary either directly or through scatter.
Uterine Damage Young women exposed to radiotherapy below the diaphragm are at risk of impaired development of the uterus in addition to ovarian failure. Long-term cancer survivors treated with total body irradiation and bone marrow transplantation are at risk of impaired uterine growth and blood flow. Despite standard estrogen replacement, the uterus size of these young girls is often reduced to 40% of normal adult size. The younger the girl is when irradiated, the more the uterus appears to be affected. It has been demonstrated in women treated with total body irradiation that sex steroid replacement in physiologic doses significantly increases uterine volume and endometrial thickness, as well as re-establishing uterine blood flow. However, it is not known whether standard regimens of estrogen replacement therapy are sufficient to facilitate uterine growth in adolescent women treated with total body irradiation in childhood.
Pregnancy after Radiation Therapy
Pregnancies achieved by survivors of childhood cancer who have received pelvic irradiation must be considered high risk due to the uterine factor.20,21 Common obstetric problems reported in these patients include early pregnancy loss, premature labor, and low birthweight infants. It is likely that radiation damage to the uterine musculature and vasculature adversely affects prospects for pregnancy in these women. Even if the uterus is able to respond to exogenous sex steroid stimulation and appropriate ARTs are available, pregnancy prognosis remains guarded.
FERTILITY PRESERVATION STRATEGIES A wide variety of strategies have been tried to preserve ovarian function and fertility in women undergoing chemotherapy or radiotherapy. However, none of them has been tested in a prospective, randomized, controlled trial. Although many of the available techniques appear promising based on preliminary studies, they all must be considered experimental at this point.
Pharmacologic Protection Gonadotropin-releasing Hormone (GnRH) Agonists
One of the first strategies attempted was to mimic the premenarchal state by administering GnRH agonists.22,23 This was based on the observation that ovaries of premenarchal girls are less sensitive to cytotoxic drugs than adult ovaries. The hypothesis is that suppressing FSH and LH elevation will inhibit the normal physiologic loss of primordial follicles by recruitment and subsequent atresia. Other possibilities include a protective effect of decreased ovarian perfusion secondary to the resultant hypoestrogenic milieu or a direct gonadal effect mediated through sphingosine-1-phosphate or germline stem cell preservation.24 The most compelling study of this approach to date was performed in primates. A prospective, randomized, controlled trial using rhesus monkeys demonstrated that administration of GnRH agonists protected the ovary against cyclophosphamideinduced damage.25 Several human studies have also shown promising results (Table 32-3). In the largest study, 90 lymphoma patients treated with chemotherapy and GnRH agonists had a premature ovarian failure rate of 7% compared to a 30% rate for patients treated with chemotherapy alone.7 Similar results were reported by others.26–29 One small prospective, controlled study of 18 women showed that GnRH agonists were not effective in the prevention of premature ovarian failure.30 The biggest weakness of these human studies is they all relied on historical controls. Because these controls necessarily had longer follow-up, it could not be determined whether the lower incidence of ovarian failure in the study groups were due to the GnRH agonist treatment or to shorter follow-up. Some investigators have questioned the theoretical value of GnRH agonist gonadal suppression in preserving ovarian function in susceptible patients.31,32 Research has shown that primordial follicles initiate follicle growth through an unknown mechanism, which is gonadotropin independent.33 GnRH-1 receptor is expressed on the human ovary, but its physiologic or pharmacologic role is unclear. However, 80% of human ovarian cancers
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Section 6 Infertility and Recurrent Pregnancy Loss Table 32-3 Summary of Gonadotropin-releasing Hormone Trials
Author
Treated Group
Control Group
Diagnosis
Incidence of Premature Ovarian Failure
Pregnancy
Blumenfeld et al.7,24,26
90
100 (partly prospective and partly retrospective)
Lymphoma
Triptorelin 3.75 mg, IM, monthly
7% in the co-treatment group, 50% in the control group
28 pregnancies in 20 patients in the treated group
Pereyra et al.27
12
5 premenarchal, 4 postmenarchal
Lymphoma
Leuprolide acetate
None of the treated group nor the premenarchal; all postmenarchal nontreated
3
Recchia et al.109
64
None
Breast cancer
Goserelin
16%
1 in 55 months’ follow-up
Fox et al.28
13
None
Breast cancer
0
4.9 months
Waxman et al.30
18
9
Hodgkin’s lymphoma
Buserelin
4 in each group
None reported
Somers et al.29
20
20
SLE
Leuprolide 3.75 mg
1 (5%) in the GnRH group and 6 (30%) in the non-GnRH group
None reported
express GnRH receptor and both GnRH agonists and antagonists inhibit the proliferation of cancer cell lines.34 Another important fact is that although mRNA expression for FSH receptors has been identified in human primordial follicles, there is no report of identification of the FSH receptor protein in these follicles.35 FSH receptor protein is uniformly present in as early as 3–4 granulosa layer preantral follicles.31 Consequently, it is possible that GnRH analogues preserve only follicles that have initiated growth, which constitute less than 10% of all the follicular pool at any given time in the ovary. Once follicle growth has been initiated, each follicle is destined either to undergo atresia or to ovulate. It is quite possible that GnRH agonist cotreatment delays the fate of these follicles, hence giving the impression that ovarian function is protected in the short run. A final observation that suggests that GnRH therapy might not work is that prepubertal children receiving heavy chemotherapy still suffer from ovarian failure.36 Meirow proposed that because younger patients have a larger ovarian reserve, absence of immediate ovarian failure does not mean that gonads are unaffected by the chemotherapy37 but simply that the patient has a sufficient number of oocytes not to demonstrate immediate failure. Given the above-mentioned arguments and counterarguments, a prospective, randomized study with sufficient power will appropriately evaluate the effectivness of GnRH analogues as a potential strategy for fertility preservation. Oral Contraceptive Pill and Progestins
Unfortunately, suppressive therapy with a variety of oral steroids such as oral contraceptives or progestins has not been shown to be effective in preventing damage from chemotherapy or radiation therapy.38–41 Apoptotic Inhibitors: A New Research Direction
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Dose of GnRH Agonist
Inhibition of apoptosis signaling events could potentially stop the apoptotic process and protect the patient from premature ovarian failure. Apoptosis plays an essential role in germ cell
dynamics, both prenatally and postnatally.42,43 Moreover, apoptosis could be activated aberrantly via chemotherapeutic drugs.44,45 Sphingosine-1-phosphate may be an example of an apoptotic inhibitor. Ceramide is a sphingolipid molecule believed to be an early messenger signaling apoptosis in response to stress. It was shown that oocytes of mice that lacked the enzyme to generate ceramide, acid sphingomyelinase, and wild type mice oocytes that had been treated with sphingosine-1-phosphate therapy resisted apoptosis induced by doxorubicin.46 With eventual identification of the molecular and genetic framework of chemotherapy-induced germ cell death, apoptotic inhibitors may some day play a role in preventing oocyte loss.
OVARIAN TRANSPOSITION Transposing the ovaries out of the field of irradiation appears to help to maintain ovarian function in patients scheduled to undergo gonadotoxic radiotherapy. Transposing the ovaries reduced the radiation dose to each ovary compared to ovaries left in their original location.47 Transposed ovaries received a dose of 126 cGy during intracavitary radiation, 135 to 90 cGy during external radiation therapy with a total dose of 4500 cGy, and 230 to 310 cGy during para-aortic node irradiation with a dose of 4500 cGy.48
Lateral versus Medial Transposition Lateral transposition appears to be more effective than medial transposition. Initial experience with medial transposition (i.e., suturing the ovaries posterior to the uterus and shielding them during treatment) showed that this approach is generally ineffective. A compilation of 10 case reports and small series showed an ovarian failure rate of 14% after lateral transposition compared to 50% after medial transposition.49 One study compared 7 cervical cancer patients who underwent lateral ovarian transposition to 9 Hodgkin’s disease patients
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Chapter 32 Fertility Preservation in Cancer Patients who underwent medial transposition, all of whom underwent radiation therapy.50 Six of the 7 patients with lateral transposition were shown to have ovaries outside the field by computed tomography (CT), and all retained ovarian function. Scattered doses to the ovaries were calculated to be 100 to 300 cGy. The 1 patient with ovaries within the field received 450 cGy and developed ovarian failure. After medial transposition, CT showed that only 3 of the 13 ovaries were outside the field. Even the 3 ovaries outside the field received approximately 300 cGy.
Lateral Ovarian Transposition Ovarian transposition can be performed by either laparotomy or laparoscopy. When laparotomy is required for the treatment of cervical cancer with radical hysterectomy or during staging of Hodgkin’s disease, lateral ovarian transposition can be performed simultaneously. However, staging laparotomy and splenectomy are no longer required for Stage I and II Hodgkin’s disease. In cases where laparotomy is not required or transposition was not done during initial laparotomy, transposition can be performed laparoscopically. There are several advantages to laparoscopic transposition; as a result, this approach has become the most common. Laparoscopic transposition can be performed as an outpatient procedure with little disruption of the planned therapeutic schedule. The ability to do this easily will eliminate unnecessary transposition in the majority of cervical cancer cases where radiation therapy is not required. An important advantage of laparoscopic ovarian transposition is that radiation therapy can be initiated immediately postoperatively, preventing failure due to the ovaries migrating back to the irradiation field.17,51,52 In cases of vaginal or cervical cancers being treated by brachytherapy, laparoscopic ovarian transposition can be performed under the same anesthetic for inserting the brachytherapy device.53 Before surgery, there should be a discussion with the radiotherapist about how far the ovaries should be moved out of the field. For example, in patients with rectal cancer the field usually goes up to the sacral promontory. Radiotherapists often request to move the ovaries above the anterior superior iliac spine. The deep inguinal ring where the round ligament inserts to course through the inguinal canal is midway between the pubic tubercle and the anterior superior iliac spine and can easily be seen at laparoscopy. The ovaries usually need to be moved above this location. Postoperatively the ovarian dose can be calculated.
abdominal peritoneum. Clips are placed so that the radiotherapist can assess where the ovaries are located. A different technique for ovarian transposition has been reported that requires less mobilization of the ovary. After transection of the utero-ovarian ligament, the ovary is not separated from the uterine tube and the ovarian vessels are completely mobilized. Although this approach has been described in a case report to have resulted in a spontaneous pregnancy,55 the technique may not allow sufficient movement of the ovaries out of the radiation field in most cases of malignancies requiring pelvic radiation if the purpose is to keep it close to the extended uterine tube. It is unlikely that a uterine tube would stretch as far as the anterior superior iliac spine. High mobilization of the ovaries without the tube has been described by Morice and colleagues.15 In this technique, the tube is not detached from the uterus but is separated from the ovary. The ovary is detached and the ovarian vessels dissected to the aortic bifurcation. The pedicle is then rotated and attached to the paracolic gutters.
Success Rates Most ovaries will maintain function if they are transposed at least 3 cm from the upper edge of the field.56 The dose of radiation that ovaries receive after transposition has been calculated. It has been shown that when cervical cancer is treated with a radiation dose of 4,000 cGy, ovaries 3 cm from the radiation field edge receive 280 cGy and those 4 cm from the field edge receive 200 cGy due to scatter.57 One study found that ovaries will maintain function when transposed above the iliac crest.58 It has been shown that approximately 80% of women undergoing laparoscopic ovarian transposition will maintain ovarian function after radiation therapy for various indications.59 The majority of women with Stage I and II Hodgkin’s disease treated with radiation alone or with minimal chemotherapy after laparoscopic ovarian transposition will retain their ovarian function and fertility.17
Surgical Technique for Lateral Ovarian Transposition There are different techniques depending on how much mobilization of the ovary is required and whether the surgeon is willing to transect the uterine tube. Transecting the tube allows the entire adnexa to be moved as a unit and has the advantage of not dissecting the mesovarium where there is anastomosis of the blood supply to the tube and ovary. The surgery starts with transection of the utero-ovarian ligament and uterine tube. The adnexa are mobilized with the ovarian vessels to the paracolic gutters. Ideally, the vascular pedicles are kept retroperitoneal to avoid tension, torsion, or trauma and bowel herniation while the ovaries remain intraperitoneal to reduce cyst formation (Fig. 32-1).54 The ovary is then sutured with nonabsorbable suture to the posterior
Figure 32–1 Transposition of the left ovary and tube. The vascular pedicle to the tube and ovary is seen going under the peritoneal bridge. The ovary is sutured to the abdominal wall. Clips are applied to visualize the ovaries when calculating the scatter radiation.
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Section 6 Infertility and Recurrent Pregnancy Loss Causes of Failure
Ovarian failure after transposition can be on the basis of several different mechanisms. Ovarian failure may result if the ovaries are not moved far enough out of the radiation field. Another reason for failure would be ovarian migration back to their original position. This may occur if absorbable suture is used. Ovarian failure after transposition may also be due to compromised ovarian blood flow from surgical technique or radiation injury to the vascular pedicle.60 Another concern with ovarian transposition is the development of symptomatic ovarian cysts. The mechanism causing the cysts is unknown but they can be surpressed with oral contraceptives.60 Fertility After Radiotherapy
Pregnancies occur after radiotherapy regardless of pretreatment ovarian transposition. In a study of 37 women, 15% became pregnant after brachytherapy with or without external radiation for vaginal or cervical clear cell carcinoma, and 80% became pregnant after external radiation for dysgerminomas and pelvic sarcomas.62 Interestingly, 75% occurred without repositioning the ovaries. Pregnancy Outcome After Radiotherapy
Several papers addressed pregnancy outcomes after pelvic radiation therapy. In a study of 31,150 atomic bomb survivors, there was no increase in stillbirth, major congenital malformations, chromosomal abnormalities, or mutations.48 Likewise, in women treated with radiotherapy for Hodgkin’s disease addition, there was no increase in stillbirths, low birthweight, congenital malformations, abnormal karyotypes, or cancer.63 However, one study found an increase in low birthweight and spontaneous abortions if conception occurred less than a year after radiation exposure.64 On this basis, it seems reasonable to advise delaying pregnancy for a year after completing radiation therapy.
ASSISTED REPRODUCTIVE TECHNOLOGY With the application of technologies to fertility preservation, new options have become available to patients requiring chemotherapy or radiotherapy. The basis of these options is in vitro fertilization (IVF). The two general approaches are (1) retrieval of immature or mature oocytes followed by cryopreservation for future IVF, and (2) retrieval of mature oocytes with immediate IVF followed by cryopreservation of the resultant embryos for later transfer.
Oocyte Cryopreservation
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The option of oocyte cryopreservation before fertilization for later IVF is considered an experimental technique and should only be performed under investigational protocol.65 Most results using this approach have been disappointing, with low survival, fertilization, and pregnancy rates after IVF of thawed oocytes.66 However, in women without partners, freezing mature or immature oocytes may be the only practical option. The main factor responsible for this outcome is the structural complexity of oocytes, which makes successful cryopreservation difficult. Oocyte subcellular organelles are far more complex and perhaps more sensitive to thermal injury than in preimplantation embryos.67,68
Recent series have demonstrated limited success rates for this approach.69–71 Either ethylene glycol or dimethylsulfoxide can be used as a cryprotectant before freezing in liquid nitrogen.69,71 Duration of oocyte storage does not seem to interfere with oocyte survival.72 On thawing, the reported mean survival rate is 68%, and the fertilization rate 48%. The pregnancy rate per thawed oocyte has been less than 2%. There have been only a limited number of established pregnancies and deliveries resulting from cryopreserved oocytes. There appears to be no increase in chromosomal abnormalities, birth defects, or developmental deficits in the children born from cryopreserved oocytes.65
Embryo Cryopreservation after IVF Embryo cryopreservation after IVF was introduced to maximize the conception chances from a single IVF cycle. With years of experience, it is clear that this option has the best chance of subsequent pregnancy for the patient. However, it is usually not acceptable to children and women without partners. The post-thaw survival rate of embryos ranges between 35% and 90%, implantation rates between 8% and 30%, and cumulative pregnancy rates can be greater than 60%.73,74 In practice, the delivery rate after transfer of previously cryopreserved embryos is approximately 19% per embryo.75 Alternative Methods for Ovarian Stimulation Before IVF
There is some concern that delay of chemotherapy and the high estrogen levels obtained during an IVF cycle may decrease longterm survival for breast cancer patients. Typically there is an interval of 6 weeks between surgery and the initiation of chemotherapy for breast cancer. Several strategies have been used in an attempt to obtain oocytes for IVF in the least amount of time with the lowest estradiol levels.76–82 Women who cryopreserved all embryos before chemotherapy produced more oocytes and embryos than those who had IVF after chemotherapy.83 As a result, some centers use natural cycle (unstimulated) recruitment prior to IVF for breast cancer patients. A single oocyte is usually aspirated. However, cancellation rates are high and pregnancy rates are very low (7.2% per cycle and 15.8% per embryo transfer).77,78 Others have used a short flare protocol rather than the standard protocol to minimize the time required to achieve follicle recruitment before IVF.76 For this technique, the initial increase in ovarian stimulation seen immediately after initiation of GnRH agonist therapy is utilized rather than waiting for the subsequent pituitary down-regulation that predictably occurs after weeks of agonist therapy. Another approach is to stimulate the ovaries before IVF with tamoxifen, a nonsteroidal antiestrogen, commonly used as a breast cancer chemopreventive agent.78 In a manner similar to clomiphene citrate, tamoxifen (40–60 mg) is started on day 2 or 3 of the cycle and given daily for 5 to 12 days. Compared to natural cycle IVF, tamoxifen will result in a significantly higher number of mature oocytes, peak estradiol, and embryos (mean of 1.6 embryos versus 0.6 embryos).78 Letrozole, an aromatase inhibitor, has been recently introduced as a promising ovulation induction agent.80 Letrozole competitively inhibits the activity of aromatase, thus preventing the conversion of androgenic substances to estrogens. Letrozole is used in the treatment of advanced-stage postmenopausal breast cancer,
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Chapter 32 Fertility Preservation in Cancer Patients because it suppresses plasma estrogen levels at doses as low as 0.1 mg/day.81 For ovulation induction before IVF, letrozole can be used independently or in combination with FSH.82 This approach is the most promising of all procedures because it requires no stimulation and minimal delay, and routine implementation requires further trials. A study of 29 women with breast cancer found similar cancer recurrence rates in those who underwent ovarian stimulation for IVF compared to those who do not.83 However, the ultimate utility of this approach is yet to be established. In vitro maturation is another potential modality for obtaining oocytes without ovarian stimulation. This technique appears effective in patients with polycystic ovary syndrome, where numerous immature oocytes can be retrieved. For this approach, no follicle-stimulating drugs are given. An ultrasound is performed on day 6 to 8 of the cycle and human chorionic gonadotropin is given. Oocyte retrieval is scheduled 36 hours later. Immature oocytes are obtained and incubated in special culture media. If the oocytes mature, as determined by extrusion of the first polar body, fertilization is attempted by intracytoplasmic injection. The embryos formed are then cryopreserved. If there is no partner, the mature oocytes are frozen.
CRYOPRESERVATION OF OVARIAN TISSUE Ovarian tissue cryopreservation and transplantation is an experimental procedure introduced to preserve fertility in women with threatened reproductive potential.84 Unlike a suspended single cell, tissue cryopreservation presents serious physical constraints related to heat and mass transfer and potential formation of ice crystals, which is responsible for the freeze– thaw injury.85 Consequently, better survival is expected from primordial follicles because of their smaller size and lack of follicular fluid. As in other reproductive technologies, animal models have provided useful information when transferring methods to treat human infertility. With the sheep ovary providing a reliable tool, Gosden and associates pioneered the sheep ovarian transplantation model. Using cryopreserved–thawed ovarian cortical strips, they showed follicular survival and endocrine function, as well as restoration of fertility after transplantation of cryopreserved– thawed ovarian cortical strips.86,87 There are several potential uses of cryopreserved ovarian tissue: transplantation back into the host, in vitro maturation of primordial follicles, and xenografting into a host animal.
Autotransplantation Cryopreserved ovarian tissue can be transplanted back into the patient. The potential for reintroduction of a cancer nidus may limit this use in malignancies known to have a predilection for the ovaries, including leukemias and potentially breast cancers. Using present techniques, ovarian tissue strips are removed from the patient before chemotherapy. They are frozen in small strips. When the patient is ready for pregnancy they are transplanted back into the patient in heterotopic or orthotopic sites. Because this is an avascular graft, ischemic injury to the transplanted tissue results in the loss of virtually the entire growing follicle population and a significant number of primordial follicles.
A summary of the experience with ovarian autotransplantation is given in Table 32-4. Several different surgical techniques have been developed for transplantation of ovarian cortical strips. In a patient with benign disease who required oophorectomy, strips of her own ovaries were subsequently transplanted into the pelvis.31 Ovarian function ceased within the first 9 months. In a 36-year-old breast cancer survivor, her own previously frozen ovarian tissue was transplanted underneath the lower abdominal skin, resulting in restoration of hormonal function.88 After multiple ovarian stimulation cycles, percutaneous oocyte aspiration followed by IVF resulted in the generation of a four-cell embryo that was transferred but did not result in pregnancy. Two cases of live birth after ovarian autotransplantation have been reported.89,90 In both cases, ovarian tissue was harvested before chemotherapy for Hodgkin’s lymphoma and was reimplanted into the residual ovary in the pelvis. Both patients re-established ovulation and became pregnant after reimplantation without medical assistance. The fact that the tissue was reimplanted into the native ovary does not exclude the possibility that ovarian function resumed from areas in the ovary that had not been removed and reimplanted. Spontaneous pregnancies have occurred in women with premature ovarian failure after chemotherapy and/or radiotherapy.6,9 This illustrates the fact that it is impossible to know the exact site of origin of the oocytes that led to pregnancies after reimplantation. One of the potential limitations of ovarian tissue cryopreservation and transplantation is loss of a large fraction of follicles during the initial ischemia after transplantation.87,91,92 Previous work indicated that whereas loss due to freezing is relatively small, up to two thirds of follicles are lost subsequent to transplantation. Given this limitation, it has been recommended that ovarian tissue freezing should be restricted to patients younger than age 35.31 Research should focus on refinement of cryopreservation protocols, better cryoprotectants, transplantation techniques that decrease ischemia, and determination of the ideal transplantation site.93–95 The practice committee of the American Society of Reproductive Medicine recommends that ovarian tissue cryopreservation or transplantation procedures should be performed only as experimental procedures under Institutional Review Board (IRB) guidelines.65
The Future In Vitro Maturation
In vitro maturation of primordial follicles obtained from frozen– thawed ovarian cortical strips is not yet possible. Unlike in vitro maturation of oocytes from antral follicles, which require days to mature, in vitro maturation of oocytes derived from primordial follicles would require months. Xenografts
Transplantation studies in severe combined immunodeficient mice clearly show that follicle maturation and completion of meiosis I in preparation for ovulation and potential fertilization can occur in xenografts.96 Concerns regarding viral infections as well as general ethical reservations may limit the use of this option in clinical practice.
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Section 6 Infertility and Recurrent Pregnancy Loss Table 32-4 Summary of Ovarian Transplantation Cases in Humans
Author
Indication
Implantation Site
Implantation Technique
Hormonal Function Restored
Ovulation Confirmed
Reproductive Functions
Follow-up
Oktay2
Benign reasons
Orthotopic beneath the left pelvic peritoneum of the ovarian fossa
Laparoscopic reimplantation of cryopreserved–thawed ovarian cortical strips
15 weeks after reimplantation after gonadotropin stimulation
Once
None
9 months
Radford3
Stage IIIB nodular sclerosing Hodgkin’s lymphoma
Orthotopic onto the left ovary and to the site of the right ovary
Laparoscopic reimplantation of cryopreserved–thawed ovarian cortical strips*
5 weeks after reimplantation spontaneously
None
None
9 months
Oktay et al.4
Stage III squamous cervical carcinoma
Heterotopic onto the left forearm
Small incision and reimplantation of fresh ovarian cortical strips
10 weeks after reimplantation after gonadotropin stimulation
Yes
3 oocytes retrieved
3 years
Oktay et al.90
Recurrent benign ovarian cysts
Heterotopic onto the left forearm
Small incision and reimplantation of fresh ovarian cortical strips
6 weeks after reimplantation spontaneously
Yes
None
3 years
Oktay et al.90
Breast cancer
Heterotopic beneath the skin of the abdomen 6 years later
Small incision
12 weeks after reimplantation after gonadotropin stimulation
Yes
20 oocytes were retrieved after 8 retrievals; one four-cell embryo developed after ICSI
N/A
Donnez et al.91
Stage IV Hodgkin’s lymphoma
Orthotopic reimplantation in a precreated peritoneal window below the normal ovary
Laparoscopic reimplantation of cryopreserved–thawed ovarian cortical strips
20 weeks after reimplantation spontaneously
Yes
Spontaneous pregnancy after 11 months of reimplantation resulted in a live birth
N/A
Meirow et al.92
Non-Hodgkin’s lymphoma
Orthotopic reimplantation in the native ovary
Laparotomy
24 weeks after reimplantation spontaneously
Yes
Pregnancy after modified IVF 24 months after reimplantation resulted in a live birth
N/A
* Ovarian tissue cryopreserved after being exposed to radiotherapy and chemotherapy ICSI = intracytoplasmic sperm injection; IVF = in vitro fertilization
FERTILITY PRESERVATION IN GYNECOLOGIC MALIGNANCIES In general, the conventional therapy for a gynecologic malignancy consists of removal of the uterus, tubes, and ovaries. However, there are three specific circumstances in patients with gynecologic malignancies that may allow a conservative approach to preserve fertility.
Early Cervical Cancer
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The first conservative approach for gynecologic malignancies would be the use of a radical trachelectomy for the treatment of early cervical cancer. This approach can be used in select cases of stage 1A2 or IB2 or earlier cervical cancer with a tumor size of 2.5 cm or less that are either squamous cell carcinoma or adenocarcinoma. Patients thus treated are at increased risk of first- and second-trimester losses, but excellent live birth rates have been reported. Stage 1A1 disease can be treated with conization if specific criteria are met. These are depth of invasion less than 3 mm and no lymphatic or vascular invasion.
Borderline Ovarian Tumors Patients with borderline ovarian tumors can be offered conservative surgery with preservation of pelvic organs, even with advanced stages. Patients treated with ovarian cystectomy rather than unilateral oophorectomy will have a higher recurrence rate. For invasive ovarian cancer, conservative surgery (oophorectomy and a staging procedure) should be reserved only for stage IA, grade 1 tumors. Malignant ovarian germ cell tumors can be treated with unilateral oophorectomy and a staging procedure.
Endometrial Adenocarcinoma Patients with adenocarcinoma of the endometrium can be treated medically if it is a grade 1 endometrial cancer with no evidence of lymph node metastasis and no evidence of myometrial or cervical invasion on magnetic resonance imaging. These patients are treated with high-dose progestins, such as megestrol 40 to 400 mg or medroxyprogesterone 200 to 800 mg. Recurrence is common, and close periodic evaluation is required to avoid significant progression, should hormonal treatment be ineffective.
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Chapter 32 Fertility Preservation in Cancer Patients FERTILITY PRESERVATION STRATEGIES IN THE MALE The goal of fertility treatment in the male is preservation of viable gametes in men who require chemotherapy or radiotherapy for a malignancy. The process is simplified by the ready availability of mature sperm in the vast majority of patients and the extensive understanding of sperm cryopreservation. However, this approach is not appropriate in some cases.
Semen Cryopreservation Semen cryopreservation followed by banking is the most commonly used option for fertility preservation after cancer therapy; it yields good results and provides a chance of establishing pregnancy. Patients diagnosed with cancer used to be considered poor candidates for sperm cryopreservation because they may present with disease-induced suboptimal semen quality and cryosensitivity. However, the deterioration in semen quality after cryopreservation–thawing in patients with cancer is similar to that of normal donors.97 The timing for sample cryopreservation is of importance. It is crucial to cryopreserve sperm before chemotherapy or radiotherapy. Samples cryopreserved after the initiation of therapy might already be impacted by changes in chromosomal structure, causing de novo mutations. In a similar manner, it is reasonable to advocate the use of contraception during chemotherapy and for 6 months afterward.
Chemotherapy Choice of Cytotoxic Regimens
For patients in the reproductive-age group, chemotherapy agents should be selected that have maximum therapeutic effects with minimum toxicity. In this context, both the type and dose of chemotherapeutic agents is important. Probably the common chemotherapy combination with the least effect on spermatogenesis is the NOVP regimen (Novantrone [mitoxantrone], Oncovin [vincristine], vinblastine, prednisone).98 Sperm production has been reported to recover rapidly within 3 to 4 months after receiving this multidrug chemotherapy despite its adverse effects on spermatogenesis.99 This rapid recovery is due to the fact that this combination damages spermatogenic germ cells but does not destroy stem cells.100 The MOPP regimen (mechlorethamine, Oncovin [vincristine], procarbazine, and prednisone) appears to have the most detrimental effects on spermatogenesis and should be avoided when possible. MOPP has been reported to permanently impair spermatogenesis in long-term cancer survivors and can lead to constant azoospermia for at least 14 months after completion of treatment in adults.103 Similarly, ChlVPP (chlorambucil, vinblastine, procarbazine, and prednisolone) can lead to irreversible damage to the germinal epithelium. Persisting high FSH levels were detected for up to 17 years after the end of therapy in patients who received ChlVPP.104 The doses of cytotoxic drugs used also play a significant role in determining the fate of spermatogenesis after therapy. Approximately 70% of patients receiving doses less than 7.5 g/m2 of cyclophosphamide recovered, but only 10% recovered when doses exceeded 7.5 g/m2.105
Testosterone Suppressors
Testosterone suppressors, such as gonadal steroids, GnRH analogues, and antiandrogens, may be tried before and during cytotoxic therapy to enhance the recovery of spermatogenesis and fertility.106 Although studies on rodent models offered promising results, clinical trials do not currently support these findings.
Gonadal Shielding for Radiotherapy Radiotherapy is significantly more toxic to testes than to ovaries. Doses as low as 0.1 Gy can have detectable effects on spermatogenesis in adult men, with doses over 2 Gy causing more permanent damage.107 Somatic cells are more resistant to chemotherapy- and radiation-induced damage than are germ cells. Indeed, Leydig cell function is not impaired until doses of 20 Gy are administered to the prepubertal boy and up to 30 Gy in sexually mature males.108 The best method for fertility preservation after cancer therapy is to minimize the testicular exposure to irradiation. The gonads should be outside the field of radiation or shielded unless they are being irradiated directly as a result of actual or potential involvement.
Testicular Tissue Harvesting Testicular tissue harvested and cryopreserved before cancer therapy is the subject of intense investigation. Establishing a successful method for testicular stem cell transplantation of frozen–thawed testicular cells would be of immense benefit for many patients undergoing sterilizing treatment, specifically prepubertal boys with childhood cancer, because no active spermatogenesis is present and no sperm cryopreservation will be feasible. Thawed tissue can subsequently be used to produce offspring in two different way ways: germ cell transplantation or in vitro maturation of stem cells. Germ cell transplantation involves the reimplantation of stored germ cells back into the patient’s own testes to restore natural fertility. In vitro maturation of stored stem cells could be later used to achieve fertilization via ICSI for IVF. Efficient protocols are still needed before these two approaches can be used clinically.
PEARLS ●
●
●
●
Candidates for fertility preservation options include those who have undergone gonadotoxic therapy for the treatment of a variety of malignant and nonmalignant conditions. The main determinants of chemotherapy-induced premature ovarian failure are the age of the patient, the drug class, cellcycle specificity, and cumulative dose of the drug. Chemotherapeutic agents are not equally gonadotoxic. Cell-cycle nonspecific agents are considered to be the most gonadotoxic category. The most important determinants of premature ovarian failure in patients undergoing radiotherapy are the patient’s age and the cumulative dose of radiation. It was also estimated that a radation dose of 6 to 8 Gy will cause permanent sterilization. There are no ideal markers to predict chemotherapy-induced gonadal damage. Day 3 serum FSH, inhibin B, antimüllerian hormone, and basal antral follicle count are the currently available options.
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Section 6 Infertility and Recurrent Pregnancy Loss ●
●
●
●
Embryo cryopreservation is the only established option with the best outcome for patients with a partner. However, it is not acceptable to prepubertal or adolescent girls or to women without a partner. Modified ovarian stimulation protocols are frequently needed to avoid a supraphysiologic rise in serum estradiol levels, which could be detrimental to the overall prognosis of the patient. Mature or immature oocyte cryopreservation may be the only option in women without a partner. The option of oocyte cryopreservation presently should be considered an experimental technique only to be performed under investigational protocol under the auspices of an IRB. Ovarian tissue cryopreservation or transplantation procedures should be performed only as experimental procedures under
●
●
●
IRB guidelines. Spontaneous pregnancy and delivery were reported in patients with Hodgkin’s and non-Hodgkin’s lymphoma from whom tissue was collected and cryopreserved before chemotherapy. Ovarian transposition requires moving the ovaries out of the pelvic irradiation field to maintain ovarian function in patients exposed to gonadotoxic radiotherapy. Ovarian transposition could be performed laparoscopically before the initiation of radiotherapy. Use of GnRH analogues as a medical protection means for gonadotoxic chemotherapy is still controversial; data are not conclusive as to its efficacy. Sperm cryopreservation is the most accepted fertility preservation strategy for male cancer patients.
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Chapter 32 Fertility Preservation in Cancer Patients 32. Oktay K, Sonmezer M, Oktem O: “Ovarian cryopreservation versus ovarian suppression by GnRH analogues: Primum non nocere”: Reply. Hum Reprod 19:1681–1683, 2004. 33. Meduri G, Touraine P, Beau I, et al: Delayed puberty and primary amenorrhea associated with a novel mutation of the human folliclestimulating hormone receptor: Clinical, histological, and molecular studies. J Clin Endocrinol Metab 88:3491–3498, 2003. 34. Emons G, Grundker C, Gunthert AR, et al: GnRH antagonists in the treatment of gynecological and breast cancers. Endoc-Rel Cancer 10:291–299, 2003. 35. Oktay K, Briggs D, Gosden RG: Ontogeny of follicle-stimulating hormone receptor gene expression in isolated human ovarian follicles. J Clin Endocrinol Metab 82:3748–3751, 1997. 36. Teinturier C, Hartmann O, Valteau-Couanet D, et al: Ovarian function after autologous bone marrow transplantation in childhood: High-dose busulfan is a major cause of ovarian failure. Bone Marrow Transplant 22:989–994, 1998. 37. Meirow D, Lewis H, Nugent D, et al: Subclinical depletion of primordial follicular reserve in mice treated with cyclophosphamide: Clinical importance and proposed accurate investigative tool. Hum Reprod 14:1903–1907, 1999. 38. Chapman RM, Sutcliffe SB: Protection of ovarian function by oral contraceptives in women receiving chemotherapy for Hodgkin’s disease. Blood 58:849–851, 1981. 39. Whitehead E, Shalet SM, Blackledge G, et al: The effect of combination chemotherapy on ovarian function in women treated for Hodgkin’s disease. Cancer 52:988–993, 1983. 40. Montz FJ, Wolff AJ, Gambone JC: Gonadal protection and fecundity rates in cyclophosphamide-treated rats. Cancer Res 51:2124–2126, 1991. 41. Familiari G, Caggiati A, Nottola SA, et al: Ultrastructure of human ovarian primordial follicles after combination chemotherapy for Hodgkin’s disease. Hum Reprod 8:2080–2087, 1993. 42. Tilly JL: Apoptosis and ovarian function. Rev Reprod 1:162–172, 1996. 43. Tilly JL: The molecular basis of ovarian cell death during germ cell attrition, follicular atresia, and luteolysis. Front Biosci 1:d1–d11, 1996. 44. Morita Y, Tilly JL: Oocyte apoptosis: Like sand through an hourglass. Dev Biol 213:1–17, 1999. 45. Tilly JL: Molecular and genetic basis of normal and toxicant-induced apoptosis in female germ cells. Toxicol Lett 102–103:497–501, 1998. 46. Morita Y, Perez GI, Paris F, et al: Oocyte apoptosis is suppressed by disruption of the acid sphingomyelinase gene or by sphingosine1–phosphate therapy. Nat Med 6:1109–1114, 2000. 47. Howell SJ, Shalet SM: Fertility preservation and management of gonadal failure associated with lymphoma therapy. Curr Oncol Rep 4:443–452, 2002. 48. Covens AL, van der Putten HW, Fyles AW, et al: Laparoscopic ovarian transposition. Eur J Gynaecol Oncol 17:177–182, 1996. 49. Howard FM: Laparoscopic lateral ovarian transposition before radiation treatment of Hodgkin disease. J Am Assoc Gynecol Laparosc 4:601–604, 1997. 50. Hadar H, Loven D, Herskovitz P, et al: An evaluation of lateral and medial transposition of the ovaries out of radiation fields. Cancer 74: 774–779, 1994. 51. Treissman MJ, Miller D, McComb PF: Laparoscopic lateral ovarian transposition. Fertil Steril 65:1229–1231, 1996. 52. Yarali H, Demirol A, Bukulmez O, et al: Laparoscopic high lateral transposition of both ovaries before pelvic irradiation. J Am Assoc Gynecol Laparosc 7:237–239, 2000. 53. Clough KB, Goffinet F, Labib A, et al: Laparoscopic unilateral ovarian transposition prior to irradiation: Prospective study of 20 cases. Cancer 77:2638–2645, 1996. 54. Anderson B, LaPolla J, Turner D, et al: Ovarian transposition in cervical cancer. Gynecol Oncol 49:206–214, 1993. 55. Bisharah M, Tulandi T: Laparoscopic preservation of ovarian function: An underused procedure. Am J Obstet Gynecol 188:367–370, 2003. 56. Bidzinski M, Lemieszczuk B, Zielinski J: Evaluation of the hormonal function and features of the ultrasound picture of transposed ovary in
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cervical cancer patients after surgery and pelvic irradiation. Eur J Gynaecol Oncol 14:77–80, 1993. van Beurden M, Schuster-Uitterhoeve AL, Lammes FB: Feasibility of transposition of the ovaries in the surgical and radiotherapeutical treatment of cervical cancer. Eur J Surg Oncol 16:141–146, 1990. Chambers SK, Chambers JT, Kier R, et al: Sequelae of lateral ovarian transposition in irradiated cervical cancer patients. Int J Radiat Oncol Biol Phys 20:1305–1308, 1991. Morice P, Castaigne D, Haie-Meder C, et al: Laparoscopic ovarian transposition for pelvic malignancies: Indications and functional outcomes. Fertil Steril 70:956–960, 1998. Feeney DD, Moore DH, Look KY, et al: The fate of the ovaries after radical hysterectomy and ovarian transposition. Gynecol Oncol 56:3–7, 1995. Chambers SK, Chambers JT, Holm C, et al: Sequelae of lateral ovarian transposition in unirradiated cervical cancer patients. Gynecol Oncol 39:155–159, 1990. Morice P, Thiam-Ba R, Castaigne D, et al: Fertility results after ovarian transposition for pelvic malignancies treated by external irradiation or brachytherapy. Hum Reprod 13:660–663, 1998. Swerdlow AJ, Jacobs PA, Marks A, et al: Fertility, reproductive outcomes, and health of offspring, of patients treated for Hodgkin’s disease: An investigation including chromosome examinations. Br J Cancer 74:291–296, 1996. Fenig E, Mishaeli M, Kalish Y, et al: Pregnancy and radiation. Cancer Treat Rev 27:1–7, 2001. Ovarian tissue and oocyte cryopreservation. Fertil Steril 82:993–998, 2004. Oktay K, Kan MT, Rosenwaks Z: Recent progress in oocyte and ovarian tissue cryopreservation and transplantation. Curr Opin Obstet Gynecol 13:263–268, 2001. Magistrini M, Szollosi D: Effects of cold and of isopropyl-N-phenylcarbamate on the second meiotic spindle of mouse oocytes. Eur J Cell Biol 22:699–707, 1980. Stachecki JJ, Cohen J, Willadsen S: Detrimental effects of sodium during mouse oocyte cryopreservation. Biol Reprod 59:395–400, 1998. Katayama KP, Stehlik J, Kuwayama M, et al: High survival rate of vitrified human oocytes results in clinical pregnancy. Fertil Steril 80:223–224, 2003. Liebermann J, Tucker MJ, Sills ES: Cryoloop vitrification in assisted reproduction: Analysis of survival rates in > 1000 human oocytes after ultra-rapid cooling with polymer augmented cryoprotectants. Clin Exp Obstet Gynecol 30:125–129, 2003. Yoon TK, Kim TJ, Park SE, et al: Live births after vitrification of oocytes in a stimulated in vitro fertilization–embryo transfer program. Fertil Steril 79:1323–1326, 2003. Porcu E, Fabbri R, Damiano G, et al: Oocyte cryopreservation in oncological patients. Eur J Obstet Gynecol Reprod Biol 113(Suppl 1): S14–S16, 2004. Wang JX, Yap YY, Matthews CD: Frozen–thawed embryo transfer: Influence of clinical factors on implantation rate and risk of multiple conception. Hum Reprod 16:2316–2319, 2001. Son WY, Yoon SH, Yoon HJ, et al: Pregnancy outcome following transfer of human blastocysts vitrified on electron microscopy grids after induced collapse of the blastocoele. Hum Reprod 18:137–139, 2003. Assisted reproductive technology in the United States: 1998 results generated from the American Society for Reproductive Medicine/ Society for Assisted Reproductive Technology Registry. Fertil Steril 77:18–31, 2002. Meniru GI, Craft I: In vitro fertilization and embryo cryopreservation prior to hysterectomy for cervical cancer. Int J Gynaecol Obstet 56:69–70, 1997. Pelinck MJ, Hoek A, Simons AH, et al: Efficacy of natural cycle IVF: A review of the literature. Hum Reprod Update 8:129–139, 2002. Oktay K, Buyuk E, Davis O, et al: Fertility preservation in breast cancer patients: IVF and embryo cryopreservation after ovarian stimulation with tamoxifen. Hum Reprod 18:90–95, 2003.
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Section 6 Infertility and Recurrent Pregnancy Loss 79. Pena JE, Chang PL, Chan LK, et al: Supraphysiological estradiol levels do not affect oocyte and embryo quality in oocyte donation cycles. Hum Reprod 17:83–87, 2002. 80. Pfister CU, Martoni A, Zamagni C, et al: Effect of age and single versus multiple dose pharmacokinetics of letrozole (Femara) in breast cancer patients. Biopharm Drug Dispos 22:191–197, 2001 81. Mouridsen H, Gershanovich M, Sun Y, et al: Phase III study of letrozole versus tamoxifen as first-line therapy of advanced breast cancer in postmenopausal women: Analysis of survival and update of efficacy from the International Letrozole Breast Cancer Group. J Clin Oncol 21:2101–2109, 2003. 82. Mitwally MF, Casper RF: Aromatase inhibition reduces gonadotrophin dose required for controlled ovarian stimulation in women with unexplained infertility. Hum Reprod 18:1588–1597, 2003. 83. Ginsburg ES, Yanushpolsky EH, Jackson KV: In vitro fertilization for cancer patients and survivors. Fertil Steril 75:705–710, 2001. 84. Oktay K, Buyuk E, Akar Z, et al: Fertility preservation in breast cancer patients: A prospective controlled comparison of ovarian stimulation with tamoxifen and letrozole for embryo cryopreservation. Fertil Steril 82:S1, 2004. 85. Oktay K: Further evidence on the safety and success of ovarian stimulation with letrozole and tamoxifen in breast cancer patients undergoing in vitro fertilization to cryopreserve their embryos for fertility preservation. J Clin Oncol 23:3858–3859, 2005. 86. Oktay K, Buyuk E: The potential of ovarian tissue transplant to preserve fertility. Expert Opin Biol Ther 2:361–370, 2002. 87. Mazur P: The role of intracellular freezing in the death of cells cooled at supraoptimal rates. Cryobiology 14:251–272, 1977. 88. Gosden RG, Baird DT, Wade JC, et al: Restoration of fertility to oophorectomized sheep by ovarian autografts stored at −196° C. Hum Reprod 9:597–603, 1994. 89. Baird DT, Webb R, Campbell BK, et al: Long-term ovarian function in sheep after ovariectomy and transplantation of autografts stored at −196° C. Endocrinology 140:462–471, 1999. 90. Oktay K, Buyuk E, Veeck L, et al: Embryo development after heterotopic transplantation of cryopreserved ovarian tissue. Lancet 363:837–840, 2004. 91. Donnez J, Dolmans MM, Demylle D, et al: Livebirth after orthotopic transplantation of cryopreserved ovarian tissue. Lancet 364:1405–1410, 2004. 92. Meirow D, Levron J, Eldar-Geva T, et al: Pregnancy after transplantation of cryopreserved ovarian tissue in a patient with ovarian failure after chemotherapy. NEJM 353:318–321, 2005. 93. Oktay K, Nugent D, Newton H, et al: Isolation and characterization of primordial follicles from fresh and cryopreserved human ovarian tissue. Fertil Steril 67:481–486, 1997. 94. Aubard Y: Ovarian tissue graft: From animal experiment to practice in the human. Eur J Obstet Gynecol Reprod Biol 86:1–3, 1999.
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95. Jeremias E, Bedaiwy MA, Biscotti C, Falcone T: Assessment of injury in cryopreserved ovarian tissue. Fertil Steril 79:651–653, 2003. 96. Jeremias E, Bedaiwy MA, Gurunluoglu R, et al: Heterotopic autotransplantation of the ovary with microvascular anastomosis: A novel surgical technique. Fertil Steril 77:1278–1282, 2002. 97. Bedaiwy MA, Jeremias E, Gurunluoglu R, et al: Restoration of ovarian function after autotransplantation of intact frozen-thawed sheep ovaries with microvascular anastomosis. Fertil Steril 79:594–602, 2003. 98. Gook DA, Edgar DH, Borg J, et al: Oocyte maturation, follicle rupture and luteinization in human cryopreserved ovarian tissue following xenografting. Hum Reprod 18:1772–1781, 2003. 99. Agarwal A, Ranganathan P, Kattal N, et al: Fertility after cancer: A prospective review of assisted reproductive outcome with banked semen specimens. Fertil Steril 81:342–348, 2004. 100. Viviani S, Santoro A, Ragni G, et al: Gonadal toxicity after combination chemotherapy for Hodgkin’s disease. Comparative results of MOPP vs. ABVD. Eur J Cancer Clin Oncol 21:601–605, 1985. 101. Dubey P, Wilson G, Mathur KK, et al: Recovery of sperm production following radiation therapy for Hodgkin’s disease after induction chemotherapy with mitoxantrone, vincristine, vinblastine, and prednisone (NOVP). Int J Radiat Oncol Biol Phys 46:609–617, 2000. 102. Meistrich ML, Wilson G, Mathur K, et al: Rapid recovery of spermatogenesis after mitoxantrone, vincristine, vinblastine, and prednisone chemotherapy for Hodgkin’s disease. J Clin Oncol 15:3488–3495, 1997. 103. Marmor D, Duyck F: Male reproductive potential after MOPP therapy for Hodgkin’s disease: A long-term survey. Andrologia 27:99–106, 1995. 104. Shafford EA, Kingston JE, Malpas JS, et al: Testicular function following the treatment of Hodgkin’s disease in childhood. Br J Cancer 68:1199–1204, 1993. 105. Meistrich ML, Wilson G, Brown BW, et al: Impact of cyclophosphamide on long-term reduction in sperm count in men treated with combination chemotherapy for Ewing and soft tissue sarcomas. Cancer 70:2703–2712, 1992. 106. Meistrich M, Shetty G: Suppression of testosterone stimulates recovery of spermatogenesis after cancer treatment. Int J Androl 26:141–146, 2003. 107. Howell SJ, Shalet SM: Effect of cancer therapy on pituitary–testicular axis. Int J Androl 25:269–276, 2002. 108. Shalet S, Tsatsoulis A, Whitehead E, et al: Vulnerability of the human Leydig cell to radiation damage is dependent upon age. J Endocrinol 120:161–165, 1989. 109. Recchia F, Siga G, De Fillipis S, et al: Goserelin as ovarian protection in the adjuvant treatment of premenopausal breast cancer: A phase II pilot study. Anticancer Drugs 13:417–424, 2002.
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33
Infections and Infertility Kristin A. Englund and Jaswant S. Bal
INTRODUCTION The connection between a woman’s infertility and her husband’s history of gonorrhea was first reported in the late 1800s. This eventually led to the discovery of gonorrhea-related pelvic inflammatory disease (PID) as an important cause of infertility in young women. At the beginning of the 20th century, only 6% of women with a history of PID ever conceived. Surgery was the mainstay of therapy. With the advent of antibiotics, this picture has improved dramatically so that medical treatment options are available to help preserve fertility. Infertility is one of the most disturbing consequences of infection of the female genital tract. Although the causes of infertility are multiple, 30% to 40% of cases are due to pelvic adhesive disease secondary to acute or chronic PID. Prevention, therefore, is the best healthcare policy in this field. Failing that, early detection and aggressive treatment are imperative. Sexually transmitted diseases (STDs) and pelvic infections are associated with a great deal of socioeconomic and cultural impact in addition to substantial morbidity. In the United States alone, 12 million cases of STDs are acquired each year, with one fourth of these occurring in teenagers. The specific pathogens involved are geographically dependent, in part as a reflection of available local healthcare and preventive services. For example, in India 15% of cases of secondary amenorrhea are related to tuberculosis. The World Health Organization estimates that, throughout the world, over 300 million episodes of curable STDs occur annually. In many parts of the developing world, a large percentage of the population is infected with one or more STDs, many of which have become antibiotic resistant. In this chapter, we discuss the wide range of pathogens that cause impaired fertility in both men and women around the world. We also discuss the anatomic location and pathologic effects of the infections. With this anatomic approach, we hope to guide the clinician to appropriate differentials and diagnostic options as they evaluate their patients for infectious causes of infertility. Finally, we review the implications for fertility of acquired immunodeficiency syndrome (AIDS).
EPIDEMIOLOGY AND PATHOPHYSIOLOGY Several pathogens associated with STDs are known to cause infertility (Table 33-1) or other syndromes (Table 33-2). In Western society the most common of these pathogens are Neisseria gonorrhoeae and Chlamydia trachomatis. However, other pathogens may influence fertility as well.
Gonorrhea There are an estimated 600,000 new cases of gonorrhea in the United States alone each year. In the United States, 75% of reported cases of gonorrhea occur in men and women between ages 15 and 29. The highest rates of infection are found in women age 15 to 19 and men age 20 to 24. The main site of infection in women is the endocervix. Patients can be asymptomatic, although more frequently symptoms occur, ranging from increased vaginal discharge to bleeding between periods, dyspareunia, and dysuria. Neisseria gonorrhoeae is a gram-negative coccus that grows in pairs, hence the term diplococcus. N. gonorrhoeae mainly infects columnar or cuboidal cells and not the squamous epithelium of a postpubertal girl. After attaching to the mucosal epithelium, it penetrates through the epithelial cells and into the submucosal tissues. Neutrophils respond and cause sloughing of the Table 33-1 Sexually Transmitted Diseases Bacteria Neisseria gonorrhoeae Chlamydia trachomatis Mycoplasma species Treponema pallidum Gardnerella vaginalis Hemophilus ducreyi Klebsiella granulomatis (Granuloma inguinale or Donovanosis) Viruses Hepatitis A, B, C Herpes simplex virus Human immunodeficiency virus, type 1 and 2 Human Papilloma virus Protozoa Trichomonas vaginalis
Table 33-2 Syndromes Associated with Curable Sexually Transmitted Diseases Pelvic inflammatory disease Infertility Ectopic pregnancy Lower genital tract disorders Vulvitis, vaginitis, cervicitis Genital ulcers or warts Liver disease Hepatitis Cirrhosis Cervical cancer
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Figure 33-1 Laparoscopic view of perihepatic adhesions (Fitz-Hugh–Curtis syndrome) that are associated with a sexually transmitted disease such as gonorrhea.
epithelium, submucosal microabscesses, and formation of pus. If left untreated, neutrophils are eventually replaced by macrophages and lymphocytes. Gonorrhea usually spreads along contiguous mucosal surfaces, producing a superficial infection. This is in contrast to staphylococci or streptococci, which tend to penetrate more deeply. Gonorrhea can then extend through the cervical os into the uterine cavity, producing endometritis. It can then spread to the fallopian tubes, causing an acute inflammatory reaction and, if not treated early enough, chronic inflammation, damage to the cilia, and ultimately scarring. Gonorrhea can also pass beyond the fimbraie of the fallopian tubes and travel up the paracolic gutters and produce an infection around the liver. This is perihepatitis, or Fitz-Hugh–Curtis syndrome (Fig. 33-1). In unusual cases, gonorrhea can produce a disseminated disease with skin rash, infectious arthritis, and rarely endocarditis. Treatment of a gonococcal infection depends on the location of the infection. If limited to the cervical region, the Centers for Disease Control and Prevention (CDC) recommends treatment with fluoroquinolones, ceftriaxone, or azithromycin (Table 33-3). Fluoroquinolone resistance in gonococci is becoming common in the Far East and Hawaii. Recently, it has begun emerging as a significant problem in some populations in the mainland United States. In men having sex with men, the prevalence of fluoroquinolone resistance has reached nearly 5%, prompting the CDC in 2004 to recommend that ofloxacin is not the drug of choice in this population.1 The resistance will continue to spread to other populations, and we will undoubtedly see further changes in the recommendations for the general population. Treatment of gonococcal infections involving the upper genital tract is discussed under Pelvic Inflammatory Disease in this chapter.
Chlamydia
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There are an estimated 3 million new cases of chlamydia in the United States each year. As with most sexually transmitted infections, these cases are more common among younger women. According to the CDC 2002 Sexually Transmitted Disease Surveillance Chlamydia Supplement, more than 5% of 15- to
Table 33-3 Sexually Transmitted Disease Treatment Guidelines for Adults Chancroid
Azithromycin 1 g po × 1 or ceftriaxone 250 mg IM in a single dose or ciprofloxacin 500 mg po BID × 3 d or erythromycin base 500 mg po TID for 7 d
Herpes simplex virus — primary
Acyclovir 400 mg po TID for 7–10 d or acyclovir 200 mg po five times a day for 7–10 d or famciclovir 250 mg po TID for 7–10 d or valacyclovir 1 g po BID for 7–10 d
Herpes simplex virus recurrences
Acyclovir 400 mg po TID for 5 days or acyclovir 800 mg po BID for 5 days or acyclovir 800 mg po TID for 2 days or famciclovir 125 mg po BID for 5 days or famciclovir 1000 mg po BID for 1 day or valacyclovir 500 mg po BID for 3 days or valacyclovir 1000 mg po for 5 days.
Herpes simplex virus — suppression
Acyclovir 400 mg PO BID or famciclovir 250 mg po BID or valacyclovir 500 mg QD or Valacyclovir 1 g po QD
Syphilis — primary and secondary
Benzathine penicillin G 2.4 million units IM × 1
Early latent syphilis
Benzathine penicillin G 2.4 million units IM × 1
Late latent syphilis
Benzathine penicillin G 7.2 million units total, administered as three doses of 2.4 million units IM at 1-week intervals
Neurosyphilis
Aqueous crystalline penicillin G 18–24 million units per day, administered as 3–4 million units q4h for 10–14 d
Chlamydia cervicitis
Azithromycin 1 g po × 1 or doxycycline 100 mg po BID for 7 d
Uncomplicated gonococcal infections of the cervix, urethra, and rectum
Ceftriaxone 125 mg IM × 1 or cefixime 400 mg po × 1 or ciprofloxacin* 500 mg po × 1 or ofloxacin* 400 mg po × 1 or levofloxacin* 250 mg po × 1 plus treatment for chlamydia if not ruled out
Bacterial vaginosis
Metronidazole 500 mg po BID × 7 d or metronidazole gel 0.75% one full applicator intravaginally qd × 5 d or clindamycin cream 2% one full applicator intravaginally qhs × 7 d
Trichomoniasis
Metronidazole 2 g po × 1 or tiridazole 2 g po × 1
Human papillomavirus — external genital warts
Patient-applied: podofilox 0.5% solution or gel BID × 3 d then none for 4 d, repeated up to 4 cycles prn or imiquimod 5% cream qhs 3 × week for up to 16 wk
Human papillomavirus — external genital warts
Provider-applied: cryotherapy q 1–2 wk or podophyllin resin 10%–25% in tincture of benzoin q wk or trichloroacetic acid q wk or surgical removal
Adapted from CDC Sexually Transmitted Diseases Treatment Guidelines 2006. MMWR 55:1–95, 2006. *Should not be used in men who have sex with men or in those with a history of recent foreign travel or partners’ travel or infection acquired in California or Hawaii.1
24-year-old women screened at family planning clinics will be found to have chlamydia. For those young women age 15 to 24 entering the National Job Training Program in 2002, the chlamydia prevalence was approximately 10%. For adolescents entering juvenile detention facilities, the prevalence of chlamydia is higher than 16%. The National Longitudinal Study of Adolescent Health (Wave III), using ligase chain reaction assays on first-void urine specimens, found chlamydia prevalence of 4% among young adults. The prevalence was greatest among minority women, including African Americans, Native Americans, and Latinos.2
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Chapter 33 Infections and Infertility The rate for young African American women was 6 times greater than for white women. From 1987 through 2002, the reported rate of chlamydial infections among all U.S. women increased nearly sixfold, from approximately 78 to 455 cases per 100,000 women. The etiology of this dramatic increase is likely multifactorial and includes increased screening, the use of the more sensitive nucleic acid amplification test (NAT), and better reporting, in addition to an increased infection rate.2 Chlamydia trachomatis is the pathologic agent of chlamydial cervical and upper genital tract infections, and certain serotypes also cause an ulcerative sexually transmitted infection termed lymphogranuloma venereum. Chlamydia cervicitis is clinically indistinguishable from gonococcal cervicitis, with symptoms of vaginal discharge, intermenstrual bleeding, dysuria, and dyspareunia. In contrast to gonorrhea, which is usually symptomatic, chlamydia is often carried asymptomatically, and permanent damage to fertility can occur without notice. Chlamydia can ascend from the cervix to the endometrium and continue to progress into the fallopian tubes, producing PID. Chlamydia can be detected using nucleic acid amplification testing of a cervical swab sample. NAT can also be used to detect chlamydia in first-void urine. This is an effective screening tool, with sensitivities comparable to those seen with cervical swabs and samples much easier to obtain. Chlamydia can also be detected with serology. This is not useful for acute cervical or upper genital tract infections, but is the only way to diagnose certain serotypes if the diagnosis of lymphogranuloma venereum is considered. The serologic studies are also useful in determining prior exposure of patients presenting with infertility. By the time a patient presents with infertility, NAT results of a cervical specimen will not likely be positive for chlamydia. Positive serology for chlamydia in this setting helps to direct an infertility workup. Cervical and upper genital tract chlamydial infections are treated with doxycycline, azithromycin, or erythromycin. The patient and all partners must be treated simultaneously. Treatment options are listed in Table 33-3.
Secondary syphilis presents on average at 6 weeks after exposure and is manifest by a diffuse skin rash that classically involves the palms and soles, verrucous-appearing genital lesions, or alopecia. This stage, if untreated, is followed by a long asymptomatic, or latent, stage. Latent syphilis refers to untreated infections that are no longer symptomatic or contagious. In many untreated patients, no further signs or symptoms of the disease will ever occur. Tertiary syphilis will eventually develop in approximately one third of untreated patients who have had secondary syphilis. Systemic spread of the bacteria can lead to damage of almost any other part of the body, most notably the brain, nervous system, bones, joints, heart, and eyes. This stage can last for decades, and can eventually lead to progressive neurologic dysfunction, cardiovascular disease, bone destruction, blindness, and death. The effect of syphilis on pregnancy has been well documented. Syphilis clearly produces miscarriages, prematurity, stillbirths, neonatal deaths, and congenital disease in the infant. The effects of syphilis on fertility are not clear, but a study out of Senegal did find that women age 40 or older with past or active syphilis were significantly more likely to have no history of gestation than women without evidence of syphilis infection.3 The diagnosis of syphilis is made using one of two screening nontreponemal blood tests, known as the rapid plasma reagin (RPR) and the Venereal Disease Research Laboratory (VDRL) tests. These tests are measured in titers that can be followed serially to evaluate treatment response. Both the RPR and VDRL usually become positive within 2 weeks of developing the chancre. If positive, one of two available confirmatory treponemal tests is required, either the fluorescent treponemal antibody absorption (FTA-ABS) test or the microhemagglutination assay for Treponema pallidum (MHA-TP) test. These will remain positive lifelong regardless of treatment status. Although syphilis may have devastating long-term consequences if not treated, this disease is relatively easy to treat once diagnosed. Penicillin is the mainstay of therapy (see Table 33-3).
Trichomonas Syphilis Syphilis was referred to as the great pox in the 1500s and affected a vast number of people in Europe. Although the incidence of syphilis saw a major decline from 1970 through 1990 in the United States, there has been a rise recently in the numbers of cases, especially among homosexual and bisexual men. In 2002, there were 6862 cases of primary and secondary syphilis reported to the CDC. There were also 412 cases of congenital syphilis. Syphilis is caused by the spirochete Treponema pallidum. This bacterium is extremely fragile, and the infection is almost exclusively transmitted by sexual contact with an infected person or from an infected pregnant woman to her unborn child. In rare circumstances, it can be passed through broken skin on other parts of the body. The course of syphilis is described as being in one of four stages: primary, secondary, latent, and tertiary (or late) syphilis. Primary syphilis begins as a painless ulcer (i.e., chancre) that develops approximately 3 weeks after exposure on the exposed area. This lesion can be difficult to detect if it is on the vaginal wall or cervix.
Trichomoniasis is a common type of vaginitis that is sexually transmitted and causes approximately 5 million genital infections in the United States each year. Although it is clearly a sexually transmitted infection, it is not a reportable disease; thus, data on its prevalence is an estimate and likely an underestimate. Trichomoniasis is caused by the single-celled motile protozoa, Trichomonas vaginalis. Infected men rarely have symptoms. In women, trichomonads cause superficial infection of the vagina and ectocervix, resulting in a foamy yellow vaginal discharge, vulvovaginal irritation, dysuria, dyspareunia or, in many cases, no symptoms at all. Although trichomonads may be cultured from the endocervix, they do not cause a clinical cervicitis. Several studies have found that women with T. vaginalis infections had an increased risk of tubal infertility (up to 1.9-fold), and that this risk increased sixfold with more than four episodes of T. vaginalis infection.4–6 These organisms have been found in the abdominal cavity of women with acute salpingitis, and there is speculation as to whether or not the motile trichomonads are able to carry bacteria or viruses to the upper genital tract.7
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Section 6 Infertility and Recurrent Pregnancy Loss Diagnosis is made most frequently using a wet mount prep of the vaginal discharge and visualizing the motile protozoa. Culture of the trichomonad is the gold standard test but is not widely used in clinical practice. A rapid test utilizing an immunochromatographic strip that can be performed rapidly in a clinical office is being evaluated for clinical use, with reported sensitivities near that of culture. Treatment is with metronidazole 2 grams orally in a single dose. Tinidazole has also been approved in the United States for treatment of trichomoniasis in a 2-gram single oral dose, but is more costly (see Table 33-3).
Human Papillomavirus
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Human papillomavirus (HPV) is one of the most common causes of sexually transmitted infections in the world. According to the CDC, there are more cases of genital HPV infections in the United States than any other STD, with at least 20 million people currently infected. At least 5 million new cases of sexually transmitted HPV infections are reported annually. Human papilloma viruses are small double-stranded circular DNA viruses. Although more than 100 different types of HPV exist, only 30 types are sexually transmitted. Many men and women with HPV infections have no symptoms. Symptomatic HPV infections manifest in women as genital warts, abnormal results on Papanicolau (Pap) smears, and both premalignant and malignant lesions of the cervix, vagina, vulva, and rectum. There are high-risk and low-risk types of HPV. Low-risk HPV types 6 and 11 are the more common causes of visible external genital warts, although any of the types that infect humans can cause warts. These lesions are often asymptomatic, although they can be painful or pruritic. The lesions can grow large enough to interfere with coitus. Perianal warts can be seen even if a patient does not have anal sex, but intra-anal warts are only seen with receptive anal intercourse. Vaginal and cervical verrucous warts can also be seen. Nucleic acid amplification testing is widely available for use with Pap smear specimens to determine the presence of highrisk HPV types. However, the external genital warts are not routinely typed. High-risk HPV types 16, 18, 31, 33, and 35 have all been associated with neoplasia, particularly of the cervix. For this reason, the presence of high-risk HPV types warrants further evaluation with colposcopy and cervical biopsies if indicated. Although HPV has not been shown to directly affect a woman’s fertility, lesions large enough to affect coitus are certainly problematic. The treatments required for localized preneoplastic or neoplastic lesions (i.e., cryotherapy, loop electrosurgical excision; see Table 33-3) can rarely cause scarring or affect the production of cervical mucosa, both of which could hinder the passage of sperm, thus affecting fertility. Invasive cervical neoplasias can require hysterectomy or other significant pelvic surgery. Treatment does not eradicate the virus; thus prevention becomes especially important for this sexually transmitted infection. Recent advances have shown that a three-dose HPV-16 vaccine prevented the development of persistent HPV-16 infection and HPV-16-related cervical neoplasia in college age women for the first 17 months after vaccination.8 This finding will certainly lead to further vaccine developments for all of the major high-risk HPV types.
Herpes Simplex Virus Genital herpes was described as early as the first part of the 18th century. It is estimated now to affect nearly 50 million Americans and is seen in all age groups. Herpes simplex virus (HSV) type 2 has been considered the main pathogen in genital herpes, but with the transmission of HSV-1 through oral sex, genital infections with that viral strain are rapidly rising. Initial clinical manifestations vary widely, but usually involve systemic symptoms of fever, malaise, headache, and myalgia that are followed within a few days by painful vesicular or pustular genital lesions that later ulcerate. Genital itching, dysuria, vaginal or urethral discharge, and inguinal lymphadenopathy are also potential clinical manifestations of genital HSV infection. Herpes simplex virus cervicitis is found in 90% of women with primary HSV-2 infections and in 70% of women with primary HSV-1 infections. The rate of cervicitis usually decreases to less than 20% with recurrent infections.9 HSV involves the squamous epithelium of the exocervix, and the ulcerative lesions can often be seen on visual examination. In rare cases, both HSV-1 and HSV-2 have been shown to extend locally and cause PID.10 Despite the ability of HSV to cause widely disseminated infection and PID, there has been no evidence that this infection contributes to infertility. Treatment is with acyclovir, valacyclovir, or famciclovir (see Table 33-3).
Mycoplasma Mycoplasma is a general term often used to refer to the class of more than 120 named species of organisms that are phylogenetically between bacteria and viruses. Of the more than 120 named species, Mycoplasma hominis, Ureaplasma urealyticum, and Mycoplasma genitalium are the most frequently recognized in relation to isolation from the human genitourinary tract. M. hominis has been found in the vagina in two thirds or more of women with abnormal vaginal discharge consistent with bacterial vaginosis, as compared with approximately 10% of women without abnormal discharge.11 Although it is strongly associated with bacterial vaginosis, the pathologic role of M. hominis in the disease is unclear. M. hominis has also been isolated from the endometrium and fallopian tubes of approximately 10% of women with salpingitis diagnosed by laparoscopy.11 The role of M. hominis as a primary pathogen is unclear because it is usually isolated with other pathologic bacteria, such as gonorrhea or chlamydia. The role of M. hominis in causing tubal infertility is also unclear. There is serologic evidence that antibodies to M. hominis have been found three times more often in infertile women with a history of PID than in controls.12 X-ray microscopy has been able to show M. genitalium binding directly to human spermatozoa and thus could be carried by motile sperm and cause upper genital tract disease in women.13 Ureaplasmas are clearly a cause of nongonococcal urethritis in men. They may cause an acute urethral syndrome in women as well. Ureaplasmas have been isolated from the fallopian tubes of patients with PID but usually in association with other known pathogens. Thus the direct role in PID is unclear.11 The diagnosis of the mycoplasmas is through culture. Serology is available but is not routinely used for clinical application. Treatment consists of doxycycline or azithromycin.
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Chapter 33 Infections and Infertility Chancroid Chancroid is a sexually transmitted infection that produces genital ulcerative lesions. Although chancroid is a significant health issue in underdeveloped nations, it is seen much less frequently in the United States. Chancroid is caused by Haemophilus ducreyi, a gram-negative anaerobic bacterium. The ulcerative lesions are typically painful and are associated with painful inguinal adenitis. Haemophilis ducreyi does not spread systemically or to distant sites and has thus not been implicated as a cause of infertility. Diagnosis is often made clinically because culture of the organism is difficult. Recommended treatment regimens include azithromycin, ceftriaxone, ciprofloxacin, and erythromycin (see Table 33-3).
Hepatitis Hepatitis A, B, and C are DNA viruses that can be sexually acquired. Hepatitis A is usually acquired through the fecal-oral route. Food-borne outbreaks have clearly been reported,14 and outbreaks in patients who practice anal receptive intercourse, mainly men having sex with men, have also been seen. Hepatitis A produces only acute infection that is usually self-limited but can be fulminant and fatal. There is no chronic form of hepatitis A. Hepatitis B is acquired through contact with blood or other body fluids. It produces an acute viral hepatitis as well as chronic disease. The chronic phase can be detected using serology for hepatitis B surface antigen (HBsAg), and the degree of viremia can then be evaluated using hepatitis B polymerase chain reaction (PCR) amplification on the blood. Prevention for hepatitis B is available in the form of a series of three vaccinations, and although vaccination is now mandatory in children, there are still many sexually active adolescents and adults who need to be screened and vaccinated. Hepatitis C is the most common chronic blood-borne infection in the United States, with nearly 3.9 million persons being infected.15 In an infertility practice, this infection is usually seen in patients who are being screened for an assisted reproductive technology (ART) procedure. The virus is most frequently acquired through contact with blood and blood products, but has been shown in several studies to be sexually transmitted.15 The risk of transmission through sexual contact is very low and far less than for HIV or hepatitis B. It is estimated that the risk of sexual transmission of hepatitis C virus from people with chronic infection varies from 0 to 0.6% if there is only one sex partner to 1% if there are multiple sex partners.16 Approximately 80% of persons exposed will develop chronic infection, with 60% of these developing chronic active liver disease. If a woman develops the chronic form of hepatitis B or C, she can become so significantly ill that ovarian dysfunction such as anovulation or amenorrhea can occur. Chronic carriers of hepatitis B or C can become a logistic issue for the in vitro fertilization laboratory. It is critical to keep viral-contaminated tissue separate from noncontaminated tissue.
Pathogenic Vaginal Flora Bacterial vaginosis is the clinical syndrome that occurs when the normal vaginal lactobacilli are replaced by other pathogenic flora, such as anaerobes, streptococci, and Gardnerella vaginalis. These
pathogens have also been found in the upper genital tracts of women with PID. For this reason, PID is often considered a polymicrobial infection. These bacteria may contribute to the development of PID when a traditional STD such as Chlamydia occurs.
Tuberculosis Tuberculosis has been found in ancient Egyptian remains, but did not become a widespread problem until the 17th and 18th centuries, when urban overcrowding facilitated the ease of spread of the bacteria through respiratory droplets. This development led to the White Plague.17 Today, tuberculosis infects 1.7 billion people worldwide, a third of the world’s population, and causes 3 million deaths each year. In the United States, rates of tuberculosis declined to a low in 1984. Since then, though, rates have begun to climb. Part of the reason for the increase is co-infection with HIV. Although tuberculosis is most commonly a pulmonary disease, it can affect virtually every organ system in the body, including the genitourinary tract. The incidence of genital tuberculosis in infertility clinics in Australia is 0.6% and in India is 19%, but tuberculosis is a rare cause of infertility in the United States.18 Mycobacterium tuberculosis is an aerobic, nonspore-forming, nonmotile bacillus that stains positively with an acid-fast stain. This bacterium is fairly large, nonmotile, and rod-shaped and is distantly related to the Actinomycetes. M. tuberculosis is an obligate aerobe, and it is for this reason that pulomonary tuberculosis usually occurs in the well-aerated upper lobes of the lungs. The bacterium is a facultative intracellular parasite. Tuberculosis is usually acquired from respiratory droplets. A pulmonary infection can spread hematogeneously to the endosalpinx, from which it may spread to the endometrium (50%), ovaries (30%), cervix (5% to 15%), or vagina (1%).17 The most common presentation of genital tuberculosis is infertility. When other symptoms are present, they are usually local and include menstrual disorders and abdominal pain. Amenorrhea may be present due to complete obliteration of the endometrial cavity, or Asherman’s syndrome, caused by postinfectious adhesions. The cervix may have an ulcerating mass that resembles carcinoma.17 By the time a woman presents with pelvic complaints or infertility, signs of the primary pulmonary infection may be completely resolved. Cultures of menstrual blood and histologic examination of endometrial tissue may be positive, but sampling error may miss the acid-fast bacilli. Tuberculosis produces midtubal occlusion with characteristic hysterosalpingographic signs, described under Fallopian Tubes in this chapter. Skin testing for tuberculosis is performed as the Mantoux test, wherein purified protein derivative (PPD) is injected intracutaneously in the forearm. The test is read within 48 to 72 hours. A Mantoux test should be performed on all women being evaluated for infertility. Treatment for tuberculosis with chemotherapy chosen according to local resistance profiles is highly effective. Surgery is rarely needed for large residual lesions or drug-resistant bacteria.
CLINICAL MANIFESTATIONS Syndromes associated with STDs can range in severity from a mild irritation to a life-threatening illness. Possible consequences
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Section 6 Infertility and Recurrent Pregnancy Loss include infertility, ectopic pregnancy, hepatitis and cirrhosis of the liver, and cervical cancer (see Table 33-2).
Pelvic Inflammatory Disease PID is the inflammatory and infectious syndrome caused by the spread of microorganisms from the lower genital tract to the endometrium, fallopian tubes, ovaries, or other pelvic structures. According to the CDC, in the United States more than 1 million women per year experience an episode of acute PID and more than 100,000 women become infertile each year as a result. Annually more than 150 women in the United States die from PID or its complications.19 Pelvic inflammatory disease is responsible for a large proportion of ectopic pregnancies. It is estimated that of women acquiring PID between ages 15 and 44, almost 1% will develop ectopic pregnancies, 1.7% will develop infertility, and almost 2% will develop chronic pelvic pain.20 It is estimated that after one episode of PID there is a 13% incidence of infertility due to tubal occlusion; after two episodes, the incidence is 35%; and after three episodes of PID, infertility approaches 75%. The most likely pathogens responsible for PID are the sexually transmitted organisms Neisseria gonorrheae and Chlamydia trachomatis. Other organisms found to contribute to PID are pathogenic vaginal flora, including anaerobes, Gardnerella vaginalis, Haemophilus influenza, enteric gram-negative rods, Streptococcus agalactiae, Mycoplasma hominis, and Ureaplasma urealyticum. Pelvic inflammatory disease can be symptomatic or subclinical. Symptoms can consist of lower abdominal tenderness, cervical motion tenderness, adnexal tenderness, mucopurulent cervicitis, and fever. Unfortunately, patients may be asymptomatic and still have enough damage to the upper genital tract to cause infertility.21 Early diagnosis and treatment are imperative to avoid the long-term complications of PID. Women who have symptomatic PID and delay seeking care (present 3 to 9 days after the onset of symptoms) are twice as likely to experience infertility as those who present within 2 days of symptoms. By 9 or more days after symptom onset, the risk for infertility and ectopic pregnancy increase to 3.5 times.22 The threshold for diagnosis must be low, so as to not miss those women with minimal symptoms. At the other end of the spectrum, some women are clearly ill enough to warrant hospital admission for PID treatment.23 Indications for hospitalization include: ● ● ● ● ● ●
inability to exclude a surgical emergency (e.g., appendicitis) pregnancy lack of response to oral antimicrobial therapy inability to follow or tolerate an outpatient oral regimen severe illness, nausea and vomiting, or high fever tubo-ovarian abscess.
The PID Evaluation and Clinical Health (PEACH) trial evaluated inpatient versus outpatient treatment regimens in 831 women with mild to moderate PID.24 This multicenter, randomized study found no difference in reproductive outcomes between women randomized to inpatient treatment and those randomized to outpatient treatment. Treatment recommendations are listed in Table 33-4.
Anatomic Areas Involved 502
Various portions of the female genital tract are affected by the organisms described in the first portion of this chapter
Table 33-4 Treatment of Pelvic Inflammatory Disease Parenteral treatment Regimen A: Cefotetan 2 g IV q12h or cefoxitin 2 g IV q6h plus doxycycline 100 mg po or IV q12h Regimen B: Clindamycin 900 mg IV q8h plus gentamicin q8h or single daily dosing Oral treatment Regimen A: Ofloxacin 400 mg po daily for 14 d or levofloxacin 500 mg po qd for 14 d with or without metronidazole 500 mg BID for 14 d Regimen B: Ceftriaxone 250 mg IM × 1 or cefoxitin 2 g IM × 1 and probenecid 1 g po × 1 or other parenteral third-generation cephalosporin plus doxycycline 100 mg po BID for 14 d with or without metronidazole 500 mg po BID for 14 d Adapted from CDC: STD Guidelines 2006. MMWR 55:1–95, 2006.
Table 33-5 Infectious Considerations at Different Anatomic Sites of Infertility Cervical Gonorrhea Chlamydia Mycoplasma Trichomonas Human papillomavirus Endometrial Tuberculosis Gonorrhea Chlamydia Schistosomiasis Tubal Gonorrhea Chlamydia Tuberculosis Schistosomiasis Anaerobes Actinomyces Overall debilitation Parasitic infections Hepatitis
(Table 33-5). The local pathologic changes in the genital tract that may affect fertility are described. Cervix
Cervical mucus is a healthy medium that, during the periovulatory period, allows sperm to move freely through the cervix to the upper genital tract. It is produced by the secretory cells of the endocervical glands and undergoes quantitative and qualitative changes during the menstrual cycle. The cervix also undergoes anatomic changes during the menstrual cycle. The external os progressively widens during the proliferative phase, reaching maximal width just before ovulation occurs. At that time, the cervical mucus is present in large amounts, facilitating passage of the spermatozoa. After ovulation, the cervical os narrows and the mucus produced decreases in amount and becomes thicker.25 Cervical factor infertility is encountered in approximately 5% of cases in clinical practice. Inflammatory processes of the cervix, such as cervicitis, could alter the physiochemical makeup of the cervical mucus and deny sperm penetration. Pathogens include gonorrhea, chlamydia, trichomonas, and G. vaginalis, streptococci (Group B streptococci), and staphylococci. The staphylococcal and streptococcal infections tend to penetrate more deeply into
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Chapter 33 Infections and Infertility the cervical wall and involve the gland acini. Gonorrhea usually spreads along contiguous mucous membrane surfaces as a superficial infection.25 Cervical stenosis can cause infertility and can be caused by chronic cervicitis and rarely from scarring resulting from treatment for HPV infections (i.e., cryotherapy, laser, or other ablative procedures). Local ablative procedures can also alter the quantity of cervical mucus due to permanent destruction of the endocervical glands. Scarring from large syphilitic chancres or cervical tuberculosis can rarely cause blockage of the cervical os. Endometrium
An extremely important step in the process of conception is endometrial implantation of the embryo. Abnormalities in the process of implantation are believed to be the basis of many cases of unexplained infertility. Some of these cases may be related to undiagnosed endometrial infections. Immune cells are part of the normal cellular population of endometrium and subendometrial areas. The cellular type is dependent on the menstrual cycle. Lymphocytes and neutrophils normally appear in the endometrium in the second half of the menstrual cycle. Their presence does not indicate endometritis. Plasma cells, however, are not normal and indicate an immune response, usually to a bacterial infection.25 Most cases of acute endometritis occur when the usually protective cervical mucosal barrier is disrupted during menses, parturition, abortion, and surgical instrumentation. Staphylococci, streptococci, N. gonorrheae, and Clostridium species are the most important causes of acute endometritis. Chronic endometritis has been associated with N. gonorrheae, C. trachomatis, M. tuberculosis, Mycoplasma, fungi, viruses, and parasites. Salpingitis and endometritis occur together frequently, with 70% to 90% of women with salpingitis also having endometritis.26 Endometrial biopsy can be used as a surrogate marker of tubal involvement and may make laparoscopy less necessary. Clearly, salpingitis has severe implications with regard to future fertility, and therefore accurate diagnosis is important. The PEACH trial26 found that endometritis itself was not associated with a reduced rate of pregnancy in women with mild to moderate PID. These findings differ from those presented in the landmark study by Westrom27 on PID and fertility on several points. First, the authors concluded that endometritis does not definitively indicate salpingitis. Westrom’s study used laparoscopic evidence of salpingitis as evidence of PID, whereas the PEACH study used endometrial biopsy, not laparoscopy. Second, the antibiotic treatment presently used is more effective than that available during Westrom’s study period, thus likely leading to fewer treatment failures. Asherman’s syndrome is the presence of intrauterine adhesions, often caused by uterine curettage, especially if performed in the postpartum period. Asherman’s syndrome can also be caused by tuberculosis or schistosomiasis. The dense adhesions, scar tissue, and even obliteration of the uterine cavity can lead to infertility.
and cilia can be damaged by infectious agents and inflammation, causing an inability to transport the ovum, sperm, or embryo; thus, although the fallopian tube is open, it is not functioning appropriately. Chlamydia trachomatis is the leading cause of permanent tubal damage worldwide. Chlamydia ascends from the cervix and preferentially invades columnar epithelial cells, which are found in abundance in the densely ciliated ampullary segment of the fallopian tubes.28 Once intracellular, Chlamydia then release a specific heat shock protein, Ch-hsp60, which is capable of inducing a local inflammatory response.29 The immune response keeps the infection from spreading to other cells, but the intracellular Chlamydia can escape immune destruction, thus setting up a chronic infection resulting in localized scarring. This chronic infection leads to the production of Ch-hsp60 antibodies, which can be detected in sera. Ch-hsp60 is similar in some regions to h-hsp60 (human heat shock protein 60). This is expressed on the decidua and embryo in early pregnancy. Thus, a woman who has developed Ch-hsp60 antibodies as a result of a previous significant fallopian tube infection could reactivate her immune system and potentially impede early embryonic events.30 Tuberculosis produces distinct pathology that can be seen on hysterosalpingography. This may reveal a shriveled uterine cavity, calcified tube or ovary, bilateral cornual block, lead pipe appearance with distension of ampullary region, or distal tubal occlusion with jagged fluffiness of tubal outline.18 Tubal obstruction caused by schistosomiasis can result in infertility.31 Inflammation of the cervix, vagina, and vulva from schistosomiasis may occur and interfere with coitus, fertility, and ability to deliver a fetus vaginally.32 Women from areas where schistosomiasis is endemic (Schistosoma mansoni in Africa, South America, and the Caribbean; Schistosoma japonicum in Japan, China, and the Phillipines; Schistosoma mekongi in Southeast Asia; Schistosoma haematobium in Africa and the Middle East; and Schistosoma intercalatum in West and central Africa) should have this included in the differential diagnosis of their infertility. Actinomyces israelii is a rare cause of pelvic abscesses, but has been associated with intrauterine device use (see Chapter 27).
Other Infertility Causes Several parasitic infections may impair a woman’s fertility due to maternal debilitation from the disease, leading to a disrupted hypothalamic-pituitary-ovarian axis. These include amebiasis, giardiasis, leishmaniasis, malaria, trypanosomiasis, and helminthic infestations with Ascaris or Trichuria. There may also be impaired fertility due to direct damage to reproductive organs from the following parasitic causes: amebiasis, Ascaris, enterobiasis, filariasis, schistosomiasis, and echinococcosis.33 Researchers in Brussels found an 80% infertility rate in mice actively infected with Trypanosoma cruzi, the protozoa that causes Chagas disease in Latin America.34
Fallopian Tubes
Fallopian tubes must be both patent and structurally functional to maintain fertility. External adhesions from prior infections (e.g., PID, appendicitis) or endometriosis can cause tubal blockage. Prior surgeries for sterilization, tubo-ovarian abscesses, or ectopic pregnancies can also block tubal passage. The fimbrae
EVALUATION OF INFECTIOUS CAUSES OF INFERTILITY Multiple infectious causes for infertility have been described, with the most common cause currently in the United States
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being Chlamydia salpingitis. Other causes must be kept in consideration when evaluating a patient with infertility, especially in patients from other parts of the world. Evaluation of the infertile couple for infectious causes should begin with an in-depth history, including episodes of prior STD exposures and treatment, possible exposures to tuberculosis, country of origin, and travel history. The next step is a thorough examination, including evaluation of the cervical mucus for signs of chronic inflammation and inspection of the cervix for signs of lesions caused by HPV, neoplasm, syphilis, or tuberculosis or for scarring from previous procedures. Cervical testing for Chlamydia and gonorrhea should be used liberally. The value of Mycoplasma and Ureaplasma culture of the cervix is less clear for infertility but may be of value in patients with recurrent pregnancy loss. Other tests should be used under specific clinical conditions. For example, a Mantoux test should be placed if tuberculosis is considered and blood RPR if syphilis is suspected. Calcified ovaries found at laparoscopy can be indicative of tuberculosis, and the patient should be appropriately tested postoperatively. Chlamydia serology may have a role in the investigation of an infertile couple. For example, if the initial investigation that includes hysterosalpingography is normal the next step has traditionally been a laparoscopy. However, if there is no history of STD or chronic pain it is unclear whether the laparoscopy will reveal any disease with sufficient frequency to outweigh the risks of the procedure. Under these circumstances Chlamydia antibody testing may help make a decision. Chlamydia antibody tests are serologic tests that measure immunoglobulin G antichlamydial antibodies. The usefulness of chlamydia antibody testing in determining the likelihood of tubal damage due to chlamydia has been examined for years. Concerns about the sensitivity of the test are based on several issues. First, the serology does not differentiate between a current chlamydial lower genital tract infection and current or prior tubal involvement. On some assays, cross-reactivity with both Chlamydia pneumoniae and gram-negative bacterial polysaccharides was present. A meta-analysis of 23 studies with a total of 2729 patients undergoing laparoscopy and serum chlamydia antibody tests found that enzyme-linked immunosorbent assays and immunofluorescence assays were the most predictive and were comparable to hysterosalpingography in the diagnosis of any tubal pathology.35 A report on 1009 women who underwent serum immunofluorescence chlamydia antibody tests and laparoscopy for evaluation of infertility found a linear trend between serum antibody tests and the likelihood of tubal damage. Low titers did not definitively rule out tubal damage, but the higher the titer, the more likely significant the tubal damage.36 This lack of sensitivity at the lower titers may be explained by the finding that, after a primary genital chlamydial infection, 18% of patients will have a twofold or greater fall in the chlamydia antibody titer within 4 years.37 In summary, chlamydia antibody testing has limitations, but it is a helpful screening tool that when applied to the appropriate subgroup (infertile women) can help identify those women who need to proceed to further, more invasive evaluation. Endometrial evaluation includes endometrial biopsy, hysterosonography, and hysterosalpingography. If a woman’s Mantoux test is positive, then the endometrial biopsy must be sent for histology, acid-fast bacillus staining, and culture. The next
step in the evaluation process would be hysterosonography or hysterosalpingography. Evidence of Asherman’s syndrome, partial or complete obliteration of the uterine cavity by scarring or fibrosis, could be infectious in nature. Depending on the woman’s prior travel or ethnic background, further evaluation of the endometrial tissue for chronic infections due to schistosomiasis or parasitic infections can be undertaken. Some infertility specialists have proposed an evaluation for tubal pathology that begins with the chlamydial serology. If negative it has been suggested that the hysterosalpingogram is not required. If suspicion is high, based on the patient’s history of prior infection, or if the serology is significant, further evaluation with hysterosalpingography or laparoscopy may be indicated. Through laparoscopy, cultures of tubal masses or from the pouch of Douglas can be obtained and may reveal infectious pathogens.
HUMAN IMMUNE DEFICIENCY VIRUS (HIV) AND ACQUIRED IMMUNODEFICIENCY SYNDROME (AIDS) As the HIV/AIDS epidemic involves more and more women, and as the treatment options are able to keep patients alive and healthy for much longer periods of time, the issues of pregnancy and infertility in the face of HIV/AIDS are being addressed. Although there is some conflicting data, HIV itself has not been proven to affect fertility. It is important to preconceptually counsel patients about the risks of transmission and the treatments available to decrease those risks. For those HIV-infected patients who desire pregnancy, the most significant risks are vertical transmission to the fetus and transmission to an uninfected partner. There is a low transmission rate to the fetus if the recommended guidelines are rigidly followed. This low risk may make refusing infertility treatment to an HIV-infected woman less valid. The risk of vertical transmission of HIV is approximately 25% without any intervention. With the use of zidovudine (AZT), the transmission decreases to 8.3%.38 The use of highly active antiretroviral treatment (HAART) or combination therapy can decrease the vertical transmission rate in optimally controlled patients to 1% to 2%.39 Optimal control of the mother’s HIV infection is critical and should be managed in conjunction with an HIV expert. If the mother’s viral load is not able to be kept under 1000 copies, then the current recommendation is for cesarean section at 38 weeks to avoid fetal exposure to maternal blood and vaginal fluids during labor and vaginal delivery.39 If the couple has discordant HIV infection status, another goal is to keep the HIV-negative partner from becoming infected. The transmission rate of HIV without the use of condoms is estimated to be 0.1% to 0.5% per sexual act.40 If the man is HIV negative and the woman is HIV positive, semen can be transferred to the vagina via methods that do not involve exposure to the uninfected male, such as insemination. This again is best done at a time when the woman’s HIV infection is optimally controlled, thus decreasing her likelihood to pass the HIV infection to the fetus. If the male is HIV infected and the female is HIV negative, the situation is much more complicated. The virus is contained within both the seminal plasma and the white blood cells in
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Chapter 33 Infections and Infertility the semen. Although it has not been conclusively shown, the spermatozoon appears to not be vector for the virus.41 Sperm washing can be accomplished by separating sperm from the seminal fluids and white blood cells, and is usually effective in 90% of samples. After sperm washing, the sample is confirmed to be negative for viral presence by reverse transcription and nested PCR. Throughout the world, several thousand ART cycles using washed sperm have been performed without transmission, but it is too early to state conclusively that this procedure is without risk.42 More clinical trials are necessary to be able to more accurately determine the risk of transmission. The final issue with all blood-borne viruses and ARTs is the potential of cross-contamination within the laboratory. To achieve the degree of safety to offer this technology to patients with such viruses would probably require separate high-security laboratory areas.43
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PEARLS ●
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Neisseria gonorrhoeae mainly infects columnar or cuboidal cells and not the squamous epithelium of a postpubertal female. The main site of infection in women is the endocervix. As with N. gonorrhoeae, Chlamydia trachomatis is an ascending infection.
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Mycoplasma hominis has been found in the vagina in two thirds or more of women with abnormal vaginal discharge consistent with bacterial vaginosis. Hepatitis C is the most common chronic blood-borne infection in the United States. Tuberculosis is usually acquired from respiratory droplets, and the pulmonary infection produces a hematogeneous focus in the endosalpinx, from which it may spread to the endometrium, ovaries, cervix, or vagina. Tuberculosis can be diagnosed with a culture of the menstrual blood, and histologic examination of endometrial tissue may be positive. It is estimated that after one episode of PID there is a 13% incidence of infertility due to tubal occlusion; after two episodes, the incidence is 35% and after 3 episodes of PID infertility approaches 75%. Chronic endometritis has been associated with N. gonorrheae, C. trachomatis, Mycobacterium tuberculosis, Mycoplasma, fungi, viruses, and parasites. HIV is contained within the seminal plasma as well as within the white blood cells in the semen but probably not the spermatozoon.
REFERENCES 1. Increases in fluoroquinolone-resistant Neisseria gonorrhoeae among men who have sex with men—United States, 2003, and revised recommendations for gonorrhea treatment, 2004. MMWR 53:335–338, 2004. 2. Centers for Disease Control and Prevention: Sexually Transmitted Disease Surveillance 2002 Supplement. Chlamydia Prevalence Monitoring Project Annual Report 2002. Atlanta: U.S. Dept. of Health and Human Services, CDC, 2003. 3. Lagarde E, Guyavarche E, Piau JP, et al: Treponemal infection rates, risk factors and pregnancy outcomes in a rural area of Senegal. Int J STD AIDS 14:208–215, 2003. 4. Soper D: Trichomoniasis: Under control or undercontrolled? Am J Obstet Gynecol 190:281–290, 2004. 5. Sherman KJ, Daling JR, Weiss NS: Sexually transmitted disease and tubal infertility. Sex Transm Dis 14:12–16, 1987. 6. Grodstein F, Goldman M, Cramer D: Relation of tubal infertility to history of sexually transmitted diseases. Am J Epidemiology 137:577–584, 1993. 7. Keith LG, Friberg J, Fullan N, et al: The possible role of Trichomonas vaginalis as a “vector” for the spread of other pathogens. Int J Fertil 31:272–277, 1986. 8. Wu TC, Boyd D: HPV-16 vaccine prevented persistent HPV-16 infection and the development of HPV-16 related cervical neoplasia. Evid Obstet Gynecol 5:42–43, 2003. 9. Corey L: Genital herpes. In Holmes KK, et al (eds). Sexually Transmitted Diseases, 2nd ed. New York, McGraw-Hill, 1990, pp 391–413. 10. Lehtinen M, Rantala I, Teisala K, et al: Detection of herpes simplex virus in women with acute pelvic inflammatory disease. J Infect Dis 152:78–81, 1985. 11. Taylor-Robinson D: Infections due to species of Mycoplasma and Ureaplasma: An update. Clin Infect Dis 23:671–684, 1996. 12. Moller BR, Taylor-Robinson D, Furr PM, et al: Serological evidence that chlamydiae and mycoplasmas are involved in infertility of women. J Reprod Fertil 73:237–240, 1985. 13. Svenstrup HF, et al: Mycoplasma genitalium attaches to human spermatozoa. Hum Reprod 18:2103–2109, 2003.
14. Fiore AE: Hepatitis A transmitted by food. Clin Infect Dis 38:705–715, 2004. 15. Centers for Disease Control and Prevention: Recommendations for prevention and control of hepatitis C virus (HCV) infection and HCVrelated chronic disease. MMWR 47(RR19):1–39, 1998. 16. Terrault NA: Sexual activity as a risk factor for hepatitis C. Hepatology 36(Suppl 1):S99–S105, 2002. 17. Haas DW, Des Prez RM: Mycobacterium tuberculosis. In Mandel GL, Bennett JE, Dolin R (eds). Principles and Practice of Infectious Diseases, 4th ed. New York, Churchill Livingstone, 1995, pp 2213–2243. 18. Gurgan T, Demirol A: Tuberculosis in assisted reproduction and infertility. Elsevier International Congress Series 1266:287–294, 2004. 19. Centers for Disease Control: Patient Fact Sheet on PID. May 2004. Available at http://www.cdc.gov/std/PID/STDFact-PID.htm. Accessed 20. Veh JM, Hook EW 3rd, Goldie SJ: A refined estimate of the average lifetime cost of pelvic inflammatory disease. Sex Transm Dis 30:369–378, 2003. 21. Gump DW, Gibson M, Ashikaga T: Evidence of prior pelvic inflammatory disease and its relationship to Chlamydia trachomatis antibody and intrauterine contraceptive device use in infertile women. Am J Obstet Gynecol 146:153–159, 1983. 22. Hillis SD, Joesoef R, Marchbanks PA, et al: Delayed care of pelvic inflammatory disease as a risk factor for impaired fertility. Am J Obstet Gynecol 168:1503–1509, 1993. 23. Centers for Disease Control and Prevention: Sexually transmitted diseases treatment guidelines 2006. MMWR 55:1–94, 2006. 24. Ness RB, Soper DE, Holley RL, et al: Effectiveness of inpatient and outpatient treatment strategies for women with pelvic inflammatory disease: Results from the pelvic inflammatory disease evaluation and clinical health (PEACH) randomized trial. Am J Obstet Gynecol 186:929–937, 2002. 25. Bristow RE, Karlan BY: Disorders of the uterine cervix. In Scott JR, Di Daia PJ, Hammond CB, Spellacy WN (eds). Danforth’s Obstetrics and Gynecology, 8th ed. Philadelphia, Lippincott Williams &Wilkins, 1999, pp 805–835. 26. Haggerty CL, Ness RB, Amortegui A, et al, for the PID Evaluation and Clinical Health (PEACH) Study. Endometritis does not predict
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27. 28. 29. 30. 31.
32. 33.
34.
35.
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reproductive morbidity after pelvic inflammatory disease. Am J Obstet Gynecol 188:141–148, 2003. Westrom L: Effect of acute pelvic inflammatory disease on fertility. Am J Obstet Gynecol 121:707–713, 1975. Land JA, Evers JLH: Chlamydia infection and subfertility. Best Prac Res Clin Obstet Gynecol 16:901–912, 2002. Paavonen J: Sexually transmitted chlamydial infections and subfertility. Elsevier International Congress Series 1266:277–286, 2004. Witkin SS: Immunological aspects of genital chlamydia infections. Best Prac Res Clin Obstet Gynecol 16:865–874, 2002. Garba M, Almoustapha T, Garba A, Nouhou H: [Extra uterine pregnancy associated with tubal schistosomiasis: Schistosoma haematobium. A case report from Niger][in French]. Bull Soc Pathol Exot 97:41–42, 2004. Bullough CHW: Infertility and bilharziasis of the female genital tract. BJOG 83:819, 1976. Sweet RL, Gibbs RS: Parasitic disease in pregnancy. In Sweet RL, Gibbs RS (eds). Infectious Diseases of the Female Genital Tract, 4th ed. Philadelphia, Lippincott Williams & Wilkins, 2002, pp 570–605. Mjihdi A, Lambot MA, Stewart IJ, et al: Acute Trypanosoma cruzi infection in mouse induces infertility or placental parasite invasion and ischemic necrosis associated with massive fetal loss. Am J Pathol 161:673–680, 2002. Mol BWJ, Dijkman B, Wertheim P, et al: The accuracy of serum chlamydial antibodies in the diagnosis of tubal pathology: A meta-analysis. Fertil Steril 67:1031–1037, 1997.
36. Akande VA, Hunt LP, Cahill DJ, et al: Tubal damage in infertile women: Prediction using chlamydia serology. Hum Reprod 18:1841–1847, 2003. 37. Gijsen AP, Land JA, Goosens VJ, et al: Chlamydia antibody testing in screening for tubal factor significance of IgG antibody decline over time. Hum Reprod 17:699–703, 2002. 38. Connor EM: Reduction of maternal-infant transmission of human immunodeficiency virus type 1 with zidovudine. Pediatric AIDS Clinical Trials Group Protocol 076 Study Group. NEJM 331:1173–1180, 1994. 39. U.S. Public Health Service Task Force: Recommendations for Use of Antiretroviral Drugs in Pregnant HIV-1-Infected Women for Maternal Health and Interventions to Reduce Perinatal HIV-1 Transmission in the United States. October 12, 2006, pp 1–65. Perinatal HIV-1 Guidelines Working Group. Published at http://aidsinfo.nih.gov. 40. DeVincenzi I: A longitudinal study of human immunodeficiency virus transmission by heterosexual partners. NEJM 331:341–346, 1994. 41. Williams CD, Finnerty JJ, Newberry YG, et al: Reproduction in couples who are affected by human immunodeficiency virus: Medical, ethical, and legal considerations. Am J Obstet Gynecol 189:333–341, 2003. 42. Englert Y, et al: Medically assisted reproduction in the presence of chronic viral diseases. Hum Reprod Update 10:149–162, 2004. 43. Gilling-Smith C, Emiliani S, Almeida P, et al: Laboratory safety during assisted reproduction in patients with blood-borne viruses. Hum Reprod 20:1433–1438, 2005.
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34
Female Infertility Gary M. Horowitz
INTRODUCTION The bearing and rearing of children are part of the ultimate life plan for most adults within our society. When those who desire children are unsuccessful in conceiving, their frustration can turn to despair, helplessness, and the need to seek advice from nearly any source: their mothers, their friends, even the mass media. Popular perceptions of the causes and cures of infertility are frequently incorrect and rarely remedial, which only increases our patients’ apprehension. Many patients will therefore present for the medical evaluation of infertility anxious, apprehensive, and full of self-recrimination. The purpose of the basic infertility workup is thus to (1) identify the likely basis of the underlying obstacle or obstacles and suggest the best evidence-based therapies, and (2) bring understanding and identity to our patients. This regard for the psychological well-being of our patients will help guide them toward successful closure regardless of the eventual success or failure of their treatment.
Definitions Infertility
Infertility is associated with a broad spectrum of definitions and classifications, indicating that it is interpreted very differently by various groups and individuals (Table 34-1). Broadly defined,
infertility depicts a diminished capability to conceive and thereby bear children. The medical definition of infertility is a 1-year period of unprotected intercourse without successful conception. Utilizing this strict interpretation, infertility is a common problem, affecting at least 10% to 15% of all couples. Based on observational data, the remaining 85% to 90% of couples attempting conception will achieve a pregnancy within that 1-year timeframe.1,2 When viewed across the entirety of their reproductive lifetimes, the problem becomes even more common, and up to 25% of women can have an episode of undesired infertility for which they actively seek medical assistance.3 This is because the desire to conceive can change markedly over the reproductive life of a woman, which is generally considered to be between ages 15 and 44. Couples additionally may not actively attempt conception continually during an entire calendar year, but sporadically across a wider timespan. It must be remembered that infertility is often a reversible state. The capacity to reproduce is a constantly shifting condition where any substantive change can lead to remarkable differences in overall cycle fecundity rates over time. The most appropriate time to pursue an infertility evaluation is therefore at the specific time that the couple is actually attempting to conceive. Laboratory values and symptom complexes can be considered to be accurate reflections of fecundability only over the short term (i.e., 6 months). Fecundability and Fecundity
Table 34-1 Basic Definitions Infertility
One-year period of unprotected intercourse without successful conception
Subfertility
An ability to conceive a pregnancy that is decreased from age-matched and population-matched controls
Fecundability
The probability that actions taken in a single menstrual cycle will result in a pregnancy
Fecundity
The probability that actions taken in a single menstrual cycle will result in a live birth
Primary infertility
A patient who has never been pregnant
Secondary infertility
A patient with a previous history of a pregnancy regardless of outcome (i.e., spontaneous abortion, ectopic pregnancy, stillbirth, or live birth)
Chemical pregnancy
A pregnancy diagnosed by a positive β-hCG titer that spontaneously aborts before clinical verification by other means such as transvaginal ultrasonography
Clinical pregnancy
A pregnancy diagnosed by a positive β-hCG titer and clinically verified, usually with transvaginal ultrasound (i.e., intrauterine sac or fetal cardiac activity) or, in cases of miscarriage, by pathologic examination
When counseling individual couples about infertility, great care must be taken when explaining the true clinical meaning of general terms such as pregnancy rates or the chances of success. The most appropriate means of direct comparison of “success” should include explanations of the words fecundability and fecundity. Fecundability refers to the probability that actions taken in a single menstrual cycle will result in a pregnancy. In contrast, fecundity is the probability that actions taken in a single menstrual cycle will result in a live birth. Normal Fecundity Rates
Success rates of specific therapies make the greatest sense when practically compared to rates found in natural conditions (i.e., in the “normal couple”) These per cycle rates of achieving conception can provide simple estimates of the efficacy of various treatment protocols and assists patients in choosing an optimum treatment plan. To appreciate the basic differences between such a normal fertile population and those that present with decreased fecundity, one must be able to appropriately define what normal truly is.
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Overall birth rates in the United States have changed markedly over the past 200 years due to an innumerable set of changes in physical, environmental, and social circumstances. The first official U.S. census was performed in 1790 and reported an overall crude birth rate of 55 per 1000 population.4 By the last completed U.S. census, the crude birth rate had decreased to only 14.1 per 1000 population, a quarter of its initial value. Changes in the crude birth rate, however, are not reflective of the true nature of fertility in humans as biologic units. To measure the true reproductive capacities of Homo sapiens sapiens as individual biologic beings, studies of fertility in the socalled natural populations should be closely examined. Natural population is a term given to groups in which couples are generally permitted to reproduce without any societal limitation to reproduction.5 The Hutterites of North America are an often utilized example of such a natural population.6–8 This sect of Swiss immigrants originally came to the New World in the mid-sixteenth century and eventually settled in several locations, all in the northern United States and southern Canada. The Hutterites are a closed and very close-knit, truly communal society. There are only six surnames within the entire social structure. All families share equally, and there is therefore no direct impetus or incentive to limit the size of the nuclear family unit. Consequently, they absolutely refuse to use contraception. Overall, the average number of pregnancies per female was 15, while the number of live births averaged 11. Remarkably, although the overall rate of infertility was only 2.4%, a marked decrease in fecundity with advancing age has been documented, with 89% of Hutterite women having their last live birth after age 34, 67% bearing children after age 40, and a mere 13% after age 45. We will discuss the effects of advancing age on fertility later in this chapter. Data from studies such as these have suggested that fertility in women generally peaks between ages 20 and 24.9,10 It remains fairly stable until approximately age 30 to 32, at which time it begins to decline progressively.11,12 This decline accelerates markedly after age 40. At a bottom line, therefore, fecundity rates in women at age 20 approximate 20% per cycle. This is the peak fecundity rate reflected in the natural setting and can be used as the gold standard when comparing success rates. Subsequently, fertility rates decrease by 4% to 8% in women age 25 to 29; 15% to 19% lower by age 30 to 34; 26% to 46% by age 35 to 39, and 95% lower at age 40 to 45.4,13 These fundamental baseline numbers must be fully understood by both practitioner and patients in order to fully understand the meaning of the relative success rates of the therapies that are being recommended. It is impossible to appropriately counsel the patients on any therapy without fully understanding these basic concepts and the overall limitations of the biology of reproduction. Over short periods of time, any cross-sectional population of infertile couples will behave in a relatively uniform manner; in other words, a statistically constant proportion will conceive with each additional cycle of treatment and follow-up. Over longer periods of time however, cycle fecundability appears to decline markedly and the overall cumulative pregnancy rate eventually plateaus.14,15 The overall pregnancy rate will never reach 100%. This is primarily due to the overall heterogeneity of infertile and sub-
Table 34-2 Fecundability Rates in a Healthy Cohort During 12 Menstrual Cycles
Cycle
Total Nonpregnant Women at Start of Cycle
Number of Pregnancies During This Cycle
Per Cycle Pregnancy Rate
1
200
59
0.30
2
137
41
0.30
3
95
16
0.17
4
78
12
0.15
5
66
14
0.21
6
52
4
0.08
7
48
5
0.10
8
43
3
0.07
9
40
2
0.05
10
38
1
0.03
11
37
2
0.05
12
35
1
0.03
Modified from Zinaman MJ, Clegg ED, Brown CC, et al: Estimates of human fertility and pregnancy loss. Fertil Steril 1996;65:503-509.
fertile populations as a whole. Those couples with the highest relative fecundity rates achieve pregnancy most rapidly and are therefore removed from the population, leaving only those couples with more serious problems remaining in the infertile pool. As an example, Zinaman and colleagues reported a prospective observational study of 200 healthy couples desiring to achieve pregnancy and followed them conservatively over a period of 12 menstrual cycles.16 The fecundability rates were highest during the first 2 months of follow-up, greater than 25% per cycle, and had dropped drastically by 6 months to less than 10% per cycle. By the end of the trial, the per cycle fecundability rate was only 3% (Table 34-2). Although this study followed couples without known fertility problems, the same basic tenets can be applied to any therapy eventually recommended to infertile couples. The fecundity rates of individual therapies will reveal this same diminution across time as the natural model. With each failed cycle of therapy, the chances of relative success with the next cycle are decreased. Not all therapies will lead to success in all patients, nor will all patients become pregnant with any therapy. It is imperative that patients fully understand this concept from the very inception of their treatment. It will greatly increase their understanding of the implications of their therapies and make it far easier to understand the possible failure of those therapies when it occurs.
CAUSES OF INFERTILITY AND SUBFERTILITY The simplest manner to express the overall causes of medical and environmental conditions that cause infertility is to divide the overall problem into male factors and female factors. One of the broadest investigations concerning these categorizations was conducted by the World Health Organization (WHO) Task Force on the Diagnosis and Treatment of Infertility in 1992.17 Although there were several significant differences in their findings
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Chapter 34 Female Infertility Table 34-3 Causes of Infertility Abnormalities of sperm production—Male factor Abnormalities in hormonal support of spermatogenesis Abnormalities in spermatogenesis Obstruction of outflow tract Inability to perform successful coitus Abnormalities in the ability to produce a fertilizable oocyte Ovulatory factor Gonadal dysgenesis (i.e., Turner’s syndrome) Premature ovarian failure Luteinized unruptured follicle syndrome Depletion of the oocyte pool by: Pelvic surgery Disease (i.e., endometriosis) Inflammatory losses (i.e., infection) Chemotherapy Abnormalities of the female reproductive tract Tubal factor Peritoneal factor Uterine factor Cervical factor Vaginal agenesis Abnormalities of implantation Luteal phase defect Hyperprolactinemia Insulin resistance Embryo–endometrial factors Abnormalities of early embryogenesis Immunologic factors Autoimmune disease Antiphospholipid syndromes Thrombophilias Recurrent pregnancy loss
depending on the economic environment of the populations studied, the data was remarkably uniform. In the developed world, infertility can be attributed solely to the female partner in 37% of couples and solely to the male partner in 8% of couples; factors can be identified in both partners in 35% of couples. No identifiable direct cause of infertility (i.e., unexplained infertility) can be found in 5% of couples. The actual percentages that individual factors are found to be the primary cause of infertility vary widely between studies. However, in a broad meta-analysis of more than 20 trials studying infertile couples, the following primary diagnoses were found: disorders of ovulation (27%), abnormal semen parameters (25%), abnormalities of the fallopian tube (22%), unexplained infertility (17%), endometriosis (5%), and other (4%).18 An additional cause is cervical factors, including cervical stenosis, which accounts for up to 5% of infertility in many series.19 Direct observations on human populations allow us to group the causes of infertility into five broad categories, listed in Table 34-3. This broad listing of root causes, although perhaps not complete, can be used as a basis for the initial evaluation of the infertile couple. The overall purpose of the evaluation is to determine which of these overall processes needs to be improved, repaired, or overcome to establish a successful pregnancy. Each question asked at the initial interview, each laboratory test requested, every diagnostic procedure performed must always reflect the need to categorize the problem as simply as possible to suggest the appropriate remedy.
Infertility and Weight Anovulation, oligo-ovulation, subfertility, and infertility have all been commonly described in women who are significantly above or below their ideal body weight.20 In one study, women with anovulatory infertility were stratified by body mass index (BMI) and compared to normal fertile controls.21 It was clear that the overall risk of ovulatory abnormality was increased with any significant variation from ideal body weight. Obese women (BMI > 27 kg/m2) had a relative risk of anovulatory infertility of 3.1 compared to women closer to their ideal body weight (BMI 20–25 kg/m2). At the same time, women with a BMI lower than 17 kg/m2 had a relative risk of anovulatory infertility of 1.6. Although the relative risk of anovulation was highest in obese women, it was also significantly increased in underweight women as well.
Stress It is difficult to specifically assess the contribution of social stress to infertility. Several studies have clearly demonstrated that stress is associated with poorer outcomes with assisted reproductive technology (ART).
INITIAL EVALUATION OF THE INFERTILE COUPLE The initial evaluation is by far the most important interview the caregiver will ever have with the infertile couple for several reasons. First, as with any initial visit, it is the primary information gathering occurrence the caregiver will share with the patients. The first evaluation will help identify the specific causes of infertility and suggest the appropriate treatment. As previously stated, with proper evaluation and treatment, the majority of women will become pregnant, and proper categorization will assist in this greatly. Second, it serves as the beginning of a partnership between caregiver and the couple that will hopefully lead to conception. The first visit helps lay down the sense of understanding and trust necessary between physician and patients, especially in such an emotionally charged situation as infertility. This understanding is vital to overcome much of the misinformation that has been gained by the patients from friends, relatives, and the mass media. Third, the patients should understand from the initial counseling session that although they have presented asking for medical advice concerning their infertility, the eventual therapeutic decisions are solely theirs to make. In the age of in vitro fertilization/embryo transfer (IVF/ET), intracytoplasmic sperm injection (ICSI), ovum donation, and the other ARTs, there are medical solutions for nearly every cause of infertility or subfertility. The patients have to realize, however, that the ultimate decision concerning what therapies are personally acceptable to them lies only within their hands. They are in control of both the direction and the intensity of suggested therapy and should be counseled to such an extent starting at the first meeting. Last, this initial evaluation should lay down the guidelines of possibility to the patients. Not all therapies will work in all patients and not all patients will become pregnant regardless of the therapy. The couple should be given a concise outline of the possibilities of care and all of the information necessary to make an intelligent decision concerning their options. When the patients
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Section 6 Infertility and Recurrent Pregnancy Loss are allowed to have such an involvement in decision making, it allows them to more easily accept the failure of any individual therapy and helps them reach closure if success is never attained.
Treating the Infertile Couple A special emphasis must be placed on treatment of the patients as a couple and not as unique individuals. The path to fertility is most certainly a dual venture that the patients must travel together. It should be strongly encouraged that both partners are present at every visit whenever possible, especially the initial evaluation. By having both patients present, it is possible to more fully understand the general attitudes concerning their infertility and their reaction to each specific therapy. It is certainly easier to answer all of their questions when they are present together. It is also easier to evaluate the frustration level of each patient if the physician sees both of them together. Treatment failures compound the general sense of failure the couples already bear and can be identified and eased by seeing the patients jointly. Talking to the patients as a pair may help them more fully understand all of the intricacies and general risks of their care, and the physician can answer any questions either of them may have concerning their options, the physician’s recommendations, and their frustrations.
Primary Elements of the Initial Infertility Evaluation The initial evaluation consists of seven primary elements (Table 34-4). It is recommended that the entire initial evaluation should be completed before direct recommendations concerning treatment are suggested to the patients. Most patients will accept a temporary delay in their therapies while full evaluation of all aspects of their clinical state is accomplished far easier than they do frequent changes in their protocol interspersed with intermittent testing and analysis.
know the answers to, especially those about family history, (2) have collated the data from other physicians concerning testing already performed and other therapies attempted, and (3) be able to better understand the nature of the first evaluation prior to their arrival. There are several versions of preprinted questionnaires available either through the American Society for Reproductive Medicine (ASRM) or from many of the pharmaceutical companies that produce the medications used in ovulation induction. In the female partner, the relevant medical history concerning the causes and the nature of infertility covers a broad range of subjects.22,23 Attention to detail during this collection of data is imperative.
Demographics It is important to determine where the patient has lived. Extragenital Mycobacterium tuberculosis infections remain one of the most common causes of pelvic inflammatory disease in the third world.24–26 In areas where tuberculosis is an endemic disease, such as Vietnam and the Philippines, tuberculus epididymitis and salpingitis are common. If recent diagnostic testing has not been done, placement of an intermediate purified protein derivative (iPPD) should be performed and the results drive further investigation. Even in the United States, up to 2% to 5% of tubal disease can be tubercular in nature.27 With any suspicion of tubercular disease, further evaluation of the female genital tract, such as endometrial biopsy and evaluation of the fallopian tubes, should be performed.
Menstrual History Information should be obtained about the following subjects: ● ●
HISTORY The data collected as part of a careful medical history will often identify signs and symptoms of a specific disease or cause and focus the evaluation on the factors responsible for the infertility. Many of the answers to the questions that should be asked, especially those concerning medical and family history and any previous evaluations, are more fully answered when the patients are specifically prepared to answer them. Sending a questionnaire to the patients before their initial evaluation is strongly recommended. By filling out these data sheets before their initial visit, the patients will be forced to (1) find out the answers to the questions that they do not immediately
● ● ●
● ● ●
●
Table 34-4 Initial Infertility Evaluation History Physical examination
●
Semen analysis
●
onset of menses development of secondary sexual characteristics, such as the development of breasts (thelarche), pubic hair (pubarche) and axillary hair, and the prepubertal growth spurt (adrenarche). If any of these events have been delayed or were aberrant in nature or timing, different diagnostic questions must be raised. cycle length and characteristics onset and severity of dysmenorrhea timing of dysmenorrhea pain in relation to cycle (e.g.,the pain of endometriosis frequently decreases with the actual onset of menstrual bleeding) mitigating factors or agents that decrease the dysmenorrhea factors that make the dysmenorrhea worse onset and severity of dysuria, especially when it occurs with the onset of menses. Endometriotic lesions of the bladder can cause significant dysuria at the time of menses. onset and severity of dyschezia. Endometriotic lesions of the rectosigmoid colon can cause significant pain at the time of menses. The nature of the stool may also change markedly. with an increase in the frequency of bowel movements and changes in the nature of the stool.28,29 presence or absence of midcycle spotting presence or absence of premenstrual symptoms
Tests of hormonal status
510
Assessment of tubal patency
Gynecologic History
Tests of ovulatory status
Gynecologic questioning should include questions about the following subjects:
Assessment of luteinization
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Chapter 34 Female Infertility ● ●
●
●
●
previous sexually transmitted diseases previous use of an intrauterine device (IUD). The association of Actinomyces israelii infections and use of IUDs has been well-documented30,31 and further evaluation such as an endometrial biopsy or evaluation of the fallopian tubes should be considered. previous abnormal Pap smear. The risks factors for human papillomavirus infection of the cervix and subsequent cervical intraepithelial neoplasia are identical as those for a previously undiagnosed sexually transmitted disease. A previous evaluation for an abnormal Pap smear should increase the degree of suspicion of concomitant tubal disease. Additionally, the diagnostic and therapeutic surgeries associated with abnormal Pap smears, such as a cold-knife cauterization or loop electrosurgical excision procedure (LEEP), can lead to cervical scar formation and stenosis and therefore cervical factor infertility. previous instrumentations of the cervical os, such as a dilatation for curettage. Any instrumentation of the os can tear the collagenous fibers of the cervix and hence lead to cervical factor infertility. previous use of hormonal contraception, including duration of use and time of discontinuation
Surgical History Past surgery, its indications, and outcomes, especially abdominal surgery, can be important. Surgeries should be listed and considered regardless of the organ system involved or the seeming lack of anatomic association with reproduction. Developmental abnormalities of the reproductive tract can frequently be associated with those of other anatomic sites.
Family History Many common genetically determined diseases, such as congenital adrenal hyperplasia, can have a significant effect on ovulation and fecundity. Such family information would be helpful in determining the need for further provocative testing of the proband. Include questions about the following: ● ● ●
●
Obstetric History Although this portion is short in women with primary infertility, couples with secondary infertility should be carefully questioned about the following subjects: ●
●
●
●
●
● ●
gravity, parity, pregnancy outcomes, and any associated complications length of time necessary to conceive each pregnancy event. This becomes especially important if the female patient has had pregnancy events with partners other than the one she is currently being evaluated with. mode of delivery with each successful pregnancy event. One of the indications for cesarean delivery is malpresentation; a common cause of malpresentation can be a müllerian anomaly.32 mode of treatment of each unsuccessful pregnancy event. Was instrumentation of the uterus used during the care of these previous losses? Instrumentation even in the best hands can lead to the formation of adhesions and the likelihood of Asherman’s syndrome. partner history. Who was the partner involved in each of the previous pregnancy events? It cannot be assumed that the current partner, the one presenting for care, was involved in these previous pregnancies. duration of infertility results of any previous evaluation and treatment of infertility
Medical History
number and age of siblings whether any or all of her siblings have children whether any or all of her siblings had any difficulty in having children her mother’s age and age of her menopause and cause (i.e., was it a natural menopause or one surgically induced?) If surgically induced, what was the indication for this surgery? Did she have difficulty in conceiving, and if so what therapies were used to achieve success?
Questions should be raised about a familial history of any of the following problems in any population: ● ● ● ● ● ●
thyroid disease atherosclerotic cardiovascular disease cancer diabetes mellitus birth defects heritable diseases. The question must be investigated as to whether there is a significant genetic risk to any child that would potentially be created through medical intervention. Populations at specific risk for genetic disease should be appropriately screened at the time of the initial evaluation per recommendations made by the ASRM (Table 34-5). Table 34-5 Genetic Screening for Various Ethnic Groups Ethnic Group
Disorder
Screening Test
Ashkenazi Jews
Tay-Sachs disease Canavan disease
Decreased serum hexosaminidase A or molecular analysis DNA analysis to detect most common alleles
African Americans
Sickle cell anemia
Presence of sickle cell hemoglobin, confirmatory hemoglobin electrophoresis
Mediterranean populations
Beta-thalassemia
Mean corpuscular volume (MCV) < 80%, followed by hemoglobin
Southeast Asians Chinese
Alpha-thalassemia
Hemoglobin electrophoresis if mean corpuscular volume < 80%
Whites of European descent Ashkenazi Jews
Cystic fibrosis
DNA analysis of specified panel of 25 CFTR gene mutations
electrophoresis
Past or current medical conditions for which the patients have been under the care of a physician can be very important; the couple should be questioned about the following: ● ● ●
●
any prescription medications either is currently taking past medical admissions to the hospital history of common communicable diseases, such as rubella, rubeola, varicella, and mumps allergies
Adapted from American Society for Reproductive Medicine: Appendix A: Minimal genetic screening for gamete donors. In 2004 Compendium of ASRM practice committee and ethics committee reports. Fertil Steril 82:S22–S23, 2004.
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Several environmental exposures covered in this section are known to have adverse effects on fertility. This part of the assessment should include questions about the following: ●
●
● ● ●
occupation and the possibility of toxic exposures in the workplace use of tobacco. Smoking can have a marked negative effect on fecundity.33–35 Smoking cessation should be discussed within the context of any medical evaluation use of alcohol use of recreational or illicit drugs use of herbal preparations, vitamin supplements, or megavitamins
The utilization of herbal preparations in the United States has reached epidemic proportions. As much as 32% of the population as a whole use some type of herbal preparation purchased over the counter,36 but less than 8% will volunteer these substances when asked openly what medications they are taking.37 Many of these products have ingredients that contain active hormones, estrogen disrupters, vasoactive amines, or antiinflammatory ingredients, all of which can have a marked effect on both the menstrual cycle and fecundity. Not all of these products are contraindicated; their ingredients should be examined by the physician for possible effects on reproduction. There are many on-line (www.pda.com or www.NaturalData base.com) and print compendiums that outline the specific nature of the herbal and vitamin ingredients of these over-the-counter supplements.38,39
Nutritional History The nutritional status of the patient should be obtained. It should be determined if the patient is taking adequate amounts of folic acid, calcium, and vitamin D. Patients should be aware of the dangers of environmental contamination in the food chain, such as mercury contamination in certain types of fresh fish.
Sexual History Coital Frequency and Timing
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It is important to be aware of the association of coital timing and the probability of successful conception (Fig. 34-1). Because activated sperm can last for up to 80 hours in the female reproductive tract,40,41 it has long been a general recommendation that intercourse occur at specific times during the menstrual cycle to ensure that at the time of expected ovulation there will be capacitated sperm available for fertilization. There can, however, be a significant diminution of both cycle and overall fecundity rates if coitus becomes too frequent.42,43 It is important to remember that coitus is usually a spontaneous expression of love between two individuals. If their love-making is placed on too specific a timed schedule, it can lead to significant performance anxiety, sexual dysfunction, and a worsening of the problem at hand. This will in turn greatly increase the already high frustration level borne by the couple. Consequently, unless there is marked male factor infertility present, there can be no clear medical justification for advising the avoidance of coitus at any time. It should be suggested to the patients that they make love at least twice a week from the cessation of menses.
Sexual Dysfunction
Whether sexual dysfunction is caused by a specific organic disease, the treatment of that disease, or the use of self-prescribed substances that interfere with sexual performance, this data should be gleaned at the outset of the evaluation. Many substances, such as many blood pressure medications, alcohol, and many recreational drugs, can lead to both erectile dysfunction in the male and desire phase sexual dysfunction in the female. Dyspareunia
Questions concerning painful intercourse should be specific to typify the type of dysfunction that this pain represents. Is the pain insertional in nature? A lack of lubrication at the initiation of coitus and the pain that it can engender does not necessarily represent the presence of an organic problem specific to the reproductive tract. Do the patients utilize an artificial lubricant on a regular basis? Although most commercially available vaginal lubricants are not spermicidal in their basic nature, their use can form an amalgam with the semen placed into the vagina during ejaculation. This may lead to a decrease in sperm motility and the number of sperm that enter the cervix. It should be suggested to the patients that alternative methods of increasing vaginal lubrication be used during times of high relative fecundity. Is there deep thrust dyspareunia? Deep thrust dyspareunia can be a very common gynecologic problem, but it is usually an episodic or intermittent complaint.44 The etiology of this symptom stems from the relative immobility of the pelvic organs and arises from rapid stretching of the uterosacral and cardinal ligaments due to the sudden movement of the cervical/uterine unit during coitus. It can also be caused by direct pressure on nodular lesions of endometriosis in the uterosacral ligaments or in the pouch of Douglas. Deep thrust dyspareunia should raise the suspicion of an organic disease, such as endometriosis or adenomyosis.45–48 Is there increased pain with orgasm? Orgasm is physiologic, typified by rhythmic contractions of the orgasmic platform and the uterus, created involuntarily by localized vasocongestion and myotonia.49 These contractions have a recorded rhythmicity of approximately 0.8 seconds, as the tension increment is released in the orgasmic platform, but accumulates slowly and more irregularly in the uterine corpus. The eventual strength of these
0.4 Probability of conception
Social History
0.3 0.2 0.1 20 -10
-8
-6
-4
-2
0
2
Day of intercourse Figure 34-1 Probability of conception according to day of coitus in relation to the day of basal body temperature (BBT) rise. Day 0 indicates day of BBT rise. (Data from From Royston JP: The probability of conception and day of timed intercourse. Biometrics 38:397, 1982.)
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Chapter 34 Female Infertility uterine contractions may be 4 to 5 times the baseline to peak intensity of a labor contraction.50 Localized production of prostaglandins and endoperoxidases in both endometriosis and adenomyosis can intensify these contractions and cause sensitization of C-afferent nerve fibers in the pelvis, thereby eliciting greater pain with each of these individual contractions.51 Marked pain with orgasm may therefore be a diagnostic suggestion of organic disease of the reproductive tract.52 Sexual Orientation
In the United States alone, an estimated 2.3 million women identify themselves as lesbians.53 Many of these women will present for medical therapy of this absolute male factor infertility, either alone or with a partner. Traditionally, many physicians have altered their history taking and diagnostic regimen in lesbian populations due to the seeming absence of significant risk factors for pelvic inflammatory disease and other sexually transmitted diseases. However, this is not always the case. Numerous studies have reported that 53% to 99% of women who identify themselves as lesbians have at some time had sex with men, and 25% to 30% of these women continue to have sex with men.54 Up to 25% of this population has been pregnant at one time, and more than 60% of those who had been pregnant report having one or more induced abortions.55 Consequently, whereas treatment of a lesbian patient or couple may lead to differing legal and ethical pathways, it is not an indication for an altered history taking or medical evaluation. Erroneous assumptions about the reproductive health and history of lesbians may place them at increased risk for delayed detection of risk factors and adverse outcomes. This in turn may decrease the success rates of any suggested therapy. Sexual orientation should be established at the initial evaluation, but the workup should remain standardized.
REVIEW OF SYSTEMS Several portions of the general review of systems must be stressed in the evaluation of the infertile female. Each is indicative of a specific hormonal or physiologic abnormality that can be closely associated with anovulation and hence with infertility or subfertility.
Visual Changes The most common presenting feature in space-occupying lesions of the pituitary, such as craniopharyngioma and macroadenomas, is visual impairment (70%).62 As the size of the pituitary increases, the relatively small area of the sella turcica forces the gland superiorly toward the optic chiasma. Compression of the optic nerve at the optic chiasma most commonly may cause bitemporal hemianopsia, or bilateral loss of the peripheral visual fields, although total blindness due to optic atrophy can occur rarely. Confrontational visual fields can be evaluated during the patient’s physical examination to evaluate any complaint of visual field abnormality.
Changes in Weight As in all of medicine, radical changes in weight in either direction may be indicative of an underlying organic problem and should be appropriately investigated.
Heat and Cold Intolerance Temperature intolerance is a common clinical feature of both hypothyroidism63 and hyperthyroidism.64 Both extremes of altered thyroxine secretion have been shown to cause menstrual irregularities and anovulation, as outlined in Chapter 19.
PHYSICAL EXAMINATION In the female partner, the physical examination may reveal pertinent medical facts that may directly affect efforts at reaching the appropriate diagnosis. Several portions of the general physical examination should be specifically stressed in the evaluation of the infertile female.
Weight and Body Mass Index The connection between increased BMI and anovulatory infertility has been discussed in this chapter under Causes of Infertility and Subfertility. Documentation of patient’s vital statistics are generally more comparable across large populations when determined as a BMI rather than a simple listing of absolute body weight and height. For example, 200 pounds is significantly different when compacted into patients of differing heights. Standardized charts for calculation of BMI are available from the ASRM.65
Headaches Patients should be questioned to find out both the frequency of self-medication with nonsteroidal anti-inflammatory drugs (NSAIDs) and the dosage taken. Headaches can be associated with pituitary lesions, such as craniopharyngiomas56,57 and prolactinomas.58,59 Prolactinomas are relatively common causes of anovulation. Each can cause hormonal derangements that lead to anovulation and infertility. Additionally, frequent headaches of any etiology may lead a patient to self-medicate with large doses of over-the-counter NSAIDs. It has been suggested that at high doses, these medications can interfere with the inflammatory processes of ovulation and implantation.60,61 Patients should also be advised to avoid taking these medications during their therapeutic protocols to prevent these abnormalities.
Thyroid Abnormalities As outlined elsewhere in this text, abnormalities of the thyroid gland can have a marked effect on the menstrual cycle and hence on fecundity. The thyroid gland is one of the largest of the endocrine glands and lies in the anterior neck, immediately below the prominence of the thyroid cartilage. The thyroid is made up of two distinct lobes joined by a thin band of connective tissue called the isthmus. The right lobe of the thyroid is normally significantly more vascular than the left and hence is often the larger of the two lobes.66 Consequently, the right lobe is more often enlarged in disorders associated with a diffuse increase in size.67 The gland itself can be examined in many manners. Many medical students are taught to examine the gland from behind
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Section 6 Infertility and Recurrent Pregnancy Loss the patient with the tips of the fingers, having the patient swallow to feel the gland in its entirety. It may be less stressful to the patient and more clinically accurate to stand directly in front of her and examine the gland directly with the tips of your dominant hand. In this manner, the tactile sense of the fingertips can be underscored by the visual references of the sternocleidomastoid muscles. It additionally allows the clinician to stand in full view of the patient and decreases the anxiety associated with the examination.
abnormal. What is abnormal to one examiner may not be to another. Standardized scoring systems such as the FerrimanGallwey72 scale and its modifications73 are useful to quantify the growth of hair. They remain limited by their subjective nature and the wide variability in score assignment and are therefore of little actual clinical use, but they can trigger a recognition of possible hyperandrogenism to help guide the direction of your laboratory examination of the patient. Acanthosis Nigricans
Breast Examination As the primary care physicians for the majority of American women, especially those of reproductive age, gynecologists have long been well-versed in the proper screening for and the evaluation of breast disease. Several aspects of the examination of the breast bear special mention in this case. Asymmetry of the Breasts
It is quite common to have some dyssymmetry in the breasts.68 This should, however, be a developmental finding and not an ongoing and progressive finding. Increasing dyssymmetry in the relative sizes of the breasts may be associated with hyperprolactinemia and organic diseases, such as varicella zoster, that in turn can lead to hyperprolactinemia.69 Most patients are aware of any relative inequality in the size and shape of their breasts, and any dyssymmetry should be directly questioned at the time of the examination. Galactorrhea
Galactorrhea is the active secretion of breast milk at a physiologically inappropriate time (i.e., a time other than during pregnancy or when the patient is actively breastfeeding a child). Usually white in color, breast milk can be differentiated from a pathologic discharge in several manners. First, secretions that have been hormonally induced usually arise from multiple ductal openings and are commonly found bilaterally. Pathologic discharges, on the other hand, are elicited from single ducts and are primarily unilateral in nature. Second, the discharge can be plated on a slide and examined and stained with Congo Red dye to detect the presence of fat globules.70 The specimen generally does not need to be sent for cytologic evaluation unless there is a suspicion of breast disease.
Abdomen The abdomen should be evaluated for evidence of an organic disease that can have a negative effect on fecundity. As an example, the violaceous striae associated with Cushing’s syndrome can be noted on the skin of the abdomen and over the hips.71 Finding these purplish streaks or marked central obesity would thereby suggest an evaluation for hypercortisolemia. Obesity itself should also trigger concern for the effects of BMI on fertility.
Skin Hirsutism
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The overgrowth of terminal hair is succinctly discussed in Chapter 18. Briefly however, there are tremendous differences in the simple connotation of the term an overgrowth of hair. What is deemed abnormal by a patient may not be physiologically
Acanthosis nigricans is characterized by hyperpigmented, velvety plaques in body folds such as the neck and axilla, although other areas can be involved as well. The formation of these characteristic plaques is stimulated by hyperinsulinemia, often the consequence of obesity-associated insulin resistance. Because insulin resistance is associated with polycystic ovary syndrome, the finding of acanthosis nigricans is an indication for further investigation. The HAIR-AN syndrome is used to refer to patients with the clinical association of hyperandrogenism, insulin resistance, and acanthosis nigricans. Tattooing and Body Piercing
These forms of self-expression have become remarkably common over the past decade for both men and women. Once regarded as deviant or markedly rebellious behavior, such body decoration has grown to such popularity that it must now be considered a mainstream expression.74 More than 26% of female college students have a tattoo, and nearly 60% have pierced some part of their bodies.75 The vast popularity of such body decoration has led to an explosion of commercial tattoo and body piercing establishments. Legal regulation unfortunately remains almost completely lacking. Two aspects of this behavior that must be considered in the evaluation of the infertile female. First, tattooing and body piercing have the potential to cause infection. Most bacterial infections are rarely serious and can be treated with antibiotics, but sexually transmitted diseases, such as syphilis, have been reported.76 Potential viral infections can be far more serious. A direct causeand-effect relationship has associated these practices with the transmission of blood-borne viral pathogens, including hepatitis B virus (HBV), hepatitis C virus (HCV), HIV-1, and HIV-2.77–79 The vertical transmission of all of these diseases may have been frequently reported and can have disastrous effects on both the mother and the fetus. Because the fertility evaluation is being performed for the sole purpose of hopefully creating a fetus and hence placing it at risk for the possible vertical transmission of serious infection, any patient with a tattoo or body piercing must be screened appropriately. If the tattoo or body piercing occurred more than 1 year before the examination, convalescent titers for viral infection are sufficient.80 If less than 1 year has elapsed, repetition of such viral screening should be considered at that anniversary. Second, piercing of the breast, such as the placement of nipple rings, must certainly be considered a substantial stimulation to prolactin secretion. Otherwise healthy-appearing women with regular cyclic menses with nipple rings may induce galactorrhea and clinically significant hyperprolactinemia.81 Discovery of such body jewelry should trigger screening of prolactin secretion. Patients should also be appropriately
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Chapter 34 Female Infertility counseled concerning the potential hormonal effects and be left to decide for themselves about the possible removal of this body adornment.
Gynecologic Examination The primary purpose of the gynecologic examination is to identify abnormal reproductive anatomy. Abnormalities in the examination suggest specific organic disease states or structural anomalies that can have marked effects on fecundity. These, in turn, focus the evaluation and direct further investigation into the causes of the patient’s complaint. Important abnormalities readily identifiable by gynecologic examination are discussed here. Clitorimegaly
In the nonerect state, the clitoris is generally 0.5 to 1.5 cm in length and partially covered by a prepuce or hood of skin. Although no consistent standard exists for clitorimegaly, it can be liberally defined as length greater than 20 mm or width greater than 10 mm. Developmental endogenous or exogenous abnormalities of the clitoris are rare. In most cases, enlargement is due to inappropriate androgen exposure. Identification of abnormal breadth and length of the clitoris will require questions about the possible ingestion of exogenous androgens or possible exposure in utero to androgenic substances taken by the patient’s mother, and will certainly tailor part of the endocrinologic screening. When clitorimegaly appears to be present on examination of the external genitalia, the clitoris must be measured. When a paper tape is used, it should be placed underneath the clitoral hood to measure its entire length, and extreme care must be used to avoid making a paper cut to the organ. A less irritating manner of measuring the length is to wet a cotton tip swab, gently place it underneath the clitoral hood, and slip it to the base of the organ. A finger can demarcate the clitoral tip; then the cotton tip swab can be held against the paper tape to define the clitoral length. Cervix Abnormalities of the Cervical Os
The traditional descriptions of the cervical os as being either parous or nulliparous are at best imprecise. There is such variation to the diameter and caliber of cervical ostia across populations that there is often no obvious distinction between individual women in these groups. The most common cervical abnormality associated with decreased fertility is cervical stenosis. Cervical stenosis decreases fertility apparently by diminishing the mucus bridge from the vagina to the endocervix necessary for sperm transport. The earliest therapeutic approaches used in the past for this problem include cervical dilation and intraperitoneal insemination. Intrauterine insemination (IUI) using washed sperm has proven to be an excellent treatment for this condition.
In the not too distant past, cervical malformations were commonly linked to in utero exposure to diethylstilbestrol (DES), which was frequently prescribed to pregnant women from the 1940s through the early 1970s to prevent miscarriages. Although in utero DES exposure is unlikely in younger women, an woman in her midthirties or older found to have a cervical malformation should be questioned about possible in utero exposure. Cervical Motion Tenderness
Cervical motion tenderness is sometimes elicited by gentle lateral movement of the cervix. Gently moving the cervix toward the patient’s right can cause the structures of the right adnexae to be stretched in the contralateral direction. An opposite movement will stretch the other adnexae. Cervical motion tenderness can be associated with either active or antecedent pelvic infection. Its physiologic basis is that movement of the cervix causes movement of the adnexae as well. If the fallopian tubes or ovaries are actively infected, this will cause sliding of inflamed parietal peritoneum on another surface, thereby causing the internal equivalent of rebound tenderness. Consequently if cervical motion during the bimanual examination elicits a painful response, an active pelvic infection should be suspected. However, other causes of cervical motion tenderness should also be considered. An important cause of cervical motion tenderness is pelvic adhesions. The adnexa can be adhered to surrounding pelvic structures as a result of previous infection or endometriosis. Even in the absence of adhesions, endometriosis can cause cervical motion tenderness when it involves pelvic structures attached to the cervix, including the vaginal apex, the uterosacral ligaments and cardinal ligaments, and the inferior portion of the broad ligaments. Abnormal Deflection of the Cervix
When the vaginal speculum is opened and the cervix visualized, it should be pointing directly down the middle of the vagina. This is because the normal structures attached bilaterally to the uterus and cervix are equal in size. Lateral deflection of the cervix can indicate that the supporting structures are shorter on one side than those on the other side. Anatomic inequalities such as this include (1) developmental abnormality such as müllerian anomaly, (2) iatrogenic changes such as surgical or obstetrical trauma, or (3) postinflammatory changes such as the damage caused by pelvic infections or endometriosis. Marked cervical deflection should increase the suspicion of organic disease and can be an indication for further radiologic or surgical evaluation of the reproductive tract. Anterior or posterior deflection of the cervix, in contrast to lateral deflection, is usually a normal variant. Anteflexion of the uterus causes posterior cervix deflection and vice versa. Contrary to popular opinion, retroflexion of the uterus is not associated with decreased fecundity. Rather, it is a normal variant found in approximately one third of women.
Abnormalities of the Ectocervix
Uterus and Adnexa Uterine Abnormalities
Malformations of the cervix can include transverse ridges, cervical collars, hoods, coxcombs, pseudopolyps, and cervical hypoplasia and agenesis.82 These uncommon malformations can be idiopathic developmental imperfections or the results of obstetrical trauma and surgery.
The bimanual examination can often identify uterine abnormalities associated with decreased fecundity, including leiomyomata, adenomyosis, or müllerian anomalies (Table 34-6). Findings such as uterine enlargement, irregularity, or tenderness are often indications for further evaluation.
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Section 6 Infertility and Recurrent Pregnancy Loss Table 34-6 Abnormalities that Can be Suspected Based on Bimanual Pelvic Examination
Table 34-7 Elements of the Infertility Evaluation Tests
Uterus
Leiomyomata Adenomyosis Müllerian anomalies Pregnancy
Fallopian tubes
Hydrosalpinx Pyosalpinx Ectopic pregnancy Hydatid cyst of Morgagni Tubo-ovarian abscess Tubo-ovarian complex Pelvic adhesive disease
Ovary
Corpus luteum Graafian follicle Residual follicular cyst Endometrioma Sclerocystic ovaries Tubo-ovarian abscess Tubo-ovarian complex
Adnexal Abnormalities
Any adnexal abnormality found during the pelvic examination should be further evaluated. The most common abnormalities found on bimanual examination that can affect fertility are listed in Table 34-6. Specific discussion of these entities can be found elsewhere in the text.
DIAGNOSTIC TESTING After the completion of a thorough medical history and physical examination, further testing is required and can be subdivided into two categories: (1) preconception screening that should be performed on every woman considering pregnancy and (2) the basic infertility evaluation that will further direct evaluation and treatment. Based on these tests or specific findings in the medical history or the physical examination, it may be necessary to perform more directed and invasive diagnostic procedures as well. An outline of such testing is listed in Table 34-7.
Preconception Screening Papanicolaou Smear
The American College of Obstetricians and Gynecologists, (ACOG) recommendations for cervical cytology screening should be followed.83 If a recent evaluation has not occurred, a Pap smear should be obtained and the results documented. If the length of infertility treatment should be spread over a period longer than a year or if the patients return for further treatment after an intervening pregnancy, the clinician can maintain a current record of Pap smear screening. Blood Type and Screen
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Blood typing and determination of Rh factor is required in all female patients considering pregnancy, if not already known.84 In Rh-negative women, antibody testing and appropriate typing of her partner are also recommended to prevent significant alloimmunization in any potential fetus created through these therapies.
Preconception Screening
Current Pap smear ABO, Rh factor typing Immunity Rubella titer Varicella convalescent titers (patients with uncertain history of infection) Appropriate genetic screening (see Table 34-5) Sexually transmitted diseases All patients VDRL/RPR Hepatitis B surface antigen (HBsAg) Chlamydia (RNA/DNA-based testing) High-risk patients Hepatitis C antibody (HCA) Gonorrhea HIV 1 and 2 Donor gametes or ART patients All tests above, plus: Cytomegalovirus (CMV) Human T-cell lymphocyte virus (HTLV) Types I and II
Infertility Testing
Semen analysis Ovulatory function Thyrotropin Prolactin Basal body temperature chart Midluteal serum progesterone Urinary LH surge detection Androgen excess Total testosterone DHEAS 17-OH progesterone, if indicated Suspicion of Cushing’s syndrome 24-hour urine for free cortisol Advanced maternal age Day 3 FSH Clomiphene citrate challenge test (CCCT) Imaging studies Vaginal ultrasonography Sonohysterography Hysterosalpingography Diagnostic laparoscopy
Rubella and Varicella Immunity
Determination of a rubella titer is recommended in all patients of childbearing age with no evidence of immunity.85,86 If a woman is found to lack immunity to rubella, she can be immunized on discovery. To date there has been no case of reported congenital rubella syndrome directly attributable to vaccination with the attenuated live virus. Regardless, the current recommendations of the CDC are for a delay of 3 months before conception due to the theoretical risk of the immunization.86 Varicella infection is uncommon in pregnancy, occurring in 0.4 to 0.7 per 1000 patients.87,88 Due to such a low incidence, recommendations for screening for varicella immunity are controversial. Universal screening has been shown not to be costeffective.89 On the other hand, the CDC considers nonpregnant women of childbearing age as a high-risk group and recommends their vaccination.90 Considering both of these factors, it is reasonable to screen infertile women actively attempting conception who have an uncertain history of past varicella infection and subsequently
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Chapter 34 Female Infertility vaccinate the seronegative among them. As with rubella vaccination, the chance of congenital varicella syndrome from inappropriate vaccination during pregnancy is very low.91 A 3-month delay of conception is also recommended after varicella immunization. Genetic Screening
The ACOG, the ASRM, and the American College of Medical Genetics recommend that appropriate genetic screening be offered to couples as part of preconception counseling.92–94 Many of these recommendations have been made in very specific populations in which carrier status for autosomal recessive disease is more common. It seems reasonable, however, to broaden this screening to autosomal recessive diseases that have higher incidences in whatever ethnic group you are evaluating. Table 34-5 lists the recommended genetic screens for some of the more common ethnic groups encountered in the United States. Testing can be performed either concurrently or sequentially, depending on the mechanism of insurance reimbursement and patient preference. Concurrent testing screens both partners simultaneously. Sequential testing screens one partner, and the second is tested only if the first is identified as a carrier. Either methodology is reasonable in most cases. Sexually Transmitted Diseases
Screening of women for sexually transmitted diseases is an important part of the infertility evaluation to detect current infections and determine women at increased risk of having pelvic adhesions related to previous infections, even in women determined to be at low risk based on history and physical examination. If donor gametes or any of the ARTs are being considered, screening of both partners is required.95 The current recommendations of the CDC for screening of pregnant women can be used as a guide to screening the infertile female.96 These recommendations call for screening all pregnant women for syphilis (Venereal Disease Research Laboratory [VDRL] or the rapid plasma reagent [RPR]), hepatitis B (hepatitis B surface antigen [HbsAg]), and Chlamydia (either RNA- or DNA-based testing). Women at moderate or high risk for sexually transmitted diseases should also be screened for gonorrhea (either culture or DNA-based testing), hepatitis C (hepatitis C antibody) and HIV-1 and 2 (ELISA). Due to the current medicolegal environment, screening for HIV should be done on a voluntary basis after consent has been obtained. For couples considering the use of donor gametes or use of ART, the ASRM recommends thorough testing of both the man and the woman. Screening tests include those listed, with the addition of cytomegalovirus (CMV) antibody and human T-cell lymphocyte virus (HTLV) types I and II.80,97,98
INFERTILITY EVALUATION Semen Analysis The evaluation of the male member of the infertile couple is unusual in that it begins with a laboratory test rather than a physical examination. The semen analysis is the foundation of screening for male infertility problems. This test provides important information about both sperm quality and quantity but does not assess sperm function.
The semen sample is analyzed for volume, viscosity, pH and color of the ejaculate, sperm concentration, motility, morphology, forward progression of the sperm, and the presence of white or red blood cells suggestive of infection. These tests are usually performed manually in a specialized laboratory, although computerassisted semen analysis has also been used. Men with persistently abnormal semen analyses should be sent to a urologist with a special interest in infertility for further evaluation. The complete evaluation of the male is covered in Chapter 35.
Tubal and Peritoneal Factors Ultrasonography
An excellent adjunct to the physical examination is transvaginal ultrasonography (see Chapter 30). Skilled examination can elicit the complete anatomy of the cervix, the endometrium, the myometrium, the fallopian tubes, the ovaries, the adnexae and the pouch of Douglas.99,100 Appropriate consultation or referral to those fully trained in such evaluations, as outlined by the guidelines of the American Institute of Ultrasound in Medicine, is strongly recommended. Conditions diagnosed by ultrasound include uterine anomalies, hydrosalpinges, and endometriomas. Because these conditions might not be detectable on physical examination and are often treatable, transvaginal ultrasound is recommended by some infertility specialists before proceeding with specific treatment. Sonohysterography and Sonohysterosalpingography
Sonohysterography is an ultrasound-based test similar to hysterosalpingography (HSG) in that a fluid medium is instilled through the cervix to evaluate the reproductive anatomy. This technique has long been used for the delineation of subtle endometrial and intracavitary lesions, such as polyps, fibroids, and endometrial cancers. Sonohysterosalpingography is a ultrasonographic technique recently developed to evaluate tubal patency by the addition of special media and power Doppler imaging or three-dimensional sonography instrumentation.101,102 Until the accuracy of this procedure can be improved, it remains an experimental procedure. Hysterosalpingography
HSG is a radiographic evaluation that allows visualization of the inside of the uterus and tubes (see Chapter 29).103 Radiographic contrast dye, either water or oil based, is injected into the uterine cavity through the vagina and cervix. The dye fills the uterine cavity and spills into the abdominal cavity if the fallopian tubes are open. An HSG will usually reveal the presence of endometrial polyps, submucous fibroids, intrauterine adhesions (synechia), uterine and vaginal septa uterine cavity abnormalities, or the aftereffect of genital tuberculosis. Many of these problems are readily visible with transvaginal ultrasound as well. More importantly, HSG can determine whether the fallopian tubes are open or blocked and whether the blockage is located proximally, at the junction of the tube and the uterus, or distally, which usually manifests as a hydrosalpinx. If tubal ligation reversal is planned, HSG will demonstrate the point at which the tubes are blocked. In some cases, HSG will detect pelvic adhesions, although pelvic adhesions are often missed with this technique.
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Diagnostic Laparoscopy
Laparoscopy is an important part of the diagnostic testing for many infertile women (see Chapter 44). It is the only way to accurately diagnose the extent of endometriosis and intraperitoneal adhesions. It is also an accurate way to accurately identify abnormalities of the uterus, fallopian tubes, and ovaries. Laparoscopy has the added advantage of being a therapeutic modality whenever endometriosis or pelvic adhesions are diagnosed. This simultaneous diagnosis and treatment adds little risk or expense to the procedure but has been well documented to improve pregnancy rates, even in mild cases. Laparoscopy has traditionally been a part of the basic female infertility evaluation. However, because of the cost and small but real risks of surgery, laparoscopy is not always performed before a trial of treatment for other causes of infertility, such as ovulatory dysfunction or male factor infertility. Most reproductive endocrinology and infertility specialists advocate doing laparoscopy in women at high risk of endometriosis or pelvic adhesions based on the results of the history and physical examination or at some time before using gonadotropins for superovulation.
Evaluation of Ovulation The only absolute proof of ovulation is conception. For practical purposes all other diagnostic tests are indirect evidence. Women who have regular menstrual cycles and have significant moliminal symptoms, such as breast tenderness, bloating, and dysmenorrhea, are most likely ovulatory. However, more accurate determination of ovulatory function is an important part of an infertility investigation. Basal Body Temperature Charts
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A basal body temperature (BBT) chart, the most traditional method for documenting ovulation, is based on the general effects of progesterone on core basal body temperature. For this test, the woman takes her temperature every morning and plots the results on graph paper. A sustained midcycle rise in temperature indicates that ovulation has probably occurred (Fig. 34-2). At rest, the BBT generally fluctuates between 97.0° and 98.0°F during the follicular phase of the menstrual cycle. Progesterone levels greater than 5 ng/mL raise the hypothalamic setpoint for basal temperature by approximately 0.6°F. Synthetic progestins, such as medroxyprogesterone acetate and norethindrone acetate, cause this same thermogenic effect. For greatest accuracy, the BBT needs to be a measurement of the basal temperature at rest before arising from bed in the morning.105 A digital thermometer is most commonly used, although an oral thermometer with a scale able to differentiate temperature to tenths of a degree will suffice. In most ovulatory women, a sustained rise in BBT is indicative of ovulation. This can occur anywhere between 1 to 5 days after the midcycle surge in luteinizing hormone (LH) and up to 4 full days after ovulation has already occurred.106 If care is not taken to minimize muscular activity before taking the temperature or the temperature rise is gradual, ovulation may
not be predicted until well after the oocyte has been released from the ovary. Classic studies on ovulation prediction and use of the BBT revealed that only 95% of biphasic cycles are ovulatory, and only 80% of monophasic cycles are actually anovulatory.107,108 This indicates a 5% false-positive rate and a 20% false-negative rate. The advantages of the BBT chart are that it is inexpensive and allows patients to become directly involved in their own care. Previous months’ data can be extrapolated in an effort to appropriately time coitus, which can be recorded on the same chart for retrospective evaluation. The disadvantage of BBTs is that they can be difficult to accurately interpret and cannot be used to prospectively predict the exact day of ovulation. The BBT remains a good method for many couples to understand their individual reproductive cycles early in the course of evaluation. As therapy progresses, they are often replaced with urinary LH detection kits or transvaginal ultrasonographic detection of preovulatory follicle growth. Serum Progesterone
Another method for documenting that ovulation has occurred is the measurement of serum progesterone levels. With the resolution of the corpus luteum from the previous menstrual cycle, serum progesterone levels remain below 1 ng/mL during most of the follicular phase. They rise during the late follicular phase to 1 to 2 ng/mL, an increase partially responsible for the change in pituitary sensitivity to gonadotropin-releasing hormone (GnRH) that creates the midcycle LH surge.109 After ovulation, progesterone levels rise steadily until they peak 7 to 8 days after ovulation. Any level of serum progesterone greater than 3 ng/mL provides reliable evidence that luteinization of the follicle, and hence ovulation, has occurred.110 A midluteal level of greater than 12 ng/mL is generally considered to be evidence of adequate ovulation and thus the absence of a luteal phase defect related to suboptimal progesterone levels. There are several ways to determine the appropriate time to measure midluteal progesterone levels. In the past, serum progesterone level was measured on day 21 of the menstrual cycle, based on the classic 28-day menstrual cycle.111 Unfortunately, normal menstrual cycles can often be much longer than this. The average cycle length of an individual patient can be used to determine the day likely to be 7 days before her next menses, which should correspond to the best date to measure midluteal progesterone. Basal Body Temperature Chart 99 Oral Temperature
Although the primary purpose of the hysterosalpingogram is not therapeutic, both oil- and water-soluble media have been shown to increase subsequent pregnancy rates by as much as fourfold.104
98.5 98 97.5 97 96.5 96 1
3
5
7
9
11 13 15 17 19 21 23 Day of Cycle
Figure 34-2
Basal body temperature (BBT) chart.
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Chapter 34 Female Infertility Probably the best way to time measurement of midluteal progesterone is with the use of a urinary LH kit. Assuming that ovulation will occur within 24 to 36 hours of the beginning of the LH surge detected in the urine, midluteal serum progesterone can best be measured 7 to 8 hours after detection of the surge. Although measurement of serum progesterone levels can be used as a documentation of ovulation and an adequate luteal phase, like the BBT, this test cannot be used to prospectively predict when ovulation will occur. Another concern is that, in some women, luteinization and progesterone production might occur without the actual release of the oocyte, a condition known as luteinized unruptured follicle syndrome.112,113 Many clinicians do not believe that this condition occurs often enough to be of clinical concern.
The endometrial biopsy is no longer recommended as part of the standard infertility evaluation. In the past, the endometrial biopsy was used as a test of luteinization and ovulation based on the known effects of progesterone secretion on the endometrium, much like a luteal phase serum progesterone level.120 Although painful and costly, this office test was once considered the gold standard for the diagnosis of luteal phase deficiency.111 However, a large multicenter study showed convincingly that out-of-phase biopsy does not discriminate between fertile and infertile women.121 Although not a standard part of the modern infertility evaluation, the endometrial biopsy remains a vital research technique in the study of the ultrastructure of the endometrium and its receptivity to embryonic implantation.
Urinary LH Measurements
Evaluating Hormonal Causes of Ovulation Dysfunction
The midcycle LH surge is the harbinger of the coming ovulation. For this reason, detection of a midcycle LH rise in the urine can predict ovulation before it happens. There are several nonprescription products available designed specifically to detect the LH surge in urine. They are simple colorimetric tests designed to change color when the urinary LH concentration exceeds a specific threshold. This threshold is specifically designed to be exceeded only at levels associated with the midcycle LH surge. To consistently detect the timing of LH surge, testing must be performed daily, generally starting 2 to 3 days before the expected day of ovulation. Assuming the standard 28-day cycle, testing should therefore begin around cycle day 12. Because the LH surge is a succinct event, generally lasting only between 48 to 50 hours, in the majority of cycles testing will only be positive on 1 day. Occasionally it will remain positive for a second day, but because the purpose of the test is to determine the start of the surge, once it is detected, testing can be stopped. Because it is a colorimetric test based on an absolute concentration, test results will vary both by the time of the day they are taken and by the patient’s general volume of fluid intake. Patients should be advised not to limit their fluid intake, just to limit it in the time immediately before the time they intend to perform the test. The first urine of the day should not be used for this test. Due to many factors, women in the northern hemisphere generally start their LH surge early in the morning. Because it takes several hours for LH to subsequently appear in the urine, the best results correlate with testing done in the late afternoon or early evening (1600 to 2200 hours).114,115 Testing twice a day will greatly decrease false-negative results but is not really necessary if testing is done regularly and at a standardized time. Ovulation will generally follow an afternoon or early evening urinary detection of LH within 14 to 26 hours.116 Consequently, if these tests are being used to time coitus or an IUI, the day after the first positive test will have the highest success rate.117 Although the accuracy of many of these ovulation predictor kits can vary, the most accurate kits predict ovulation within the next 24 to 48 hours with 90% accuracy.116,118,119 Most kits are comparatively easy to read, noninvasive, and relatively inexpensive, generally costing around $30 to $35/month. The disadvantage is that accurately reading them can be difficult for some patients.
Endometrial Biopsy
Thyrotropin
Hypothyroidism, a relatively common problem in women, can present as ovulation dysfunction with few other symptoms. The simplest screening test for hypothyroidism is the measurement of thyrotropin. It is reflective of all feedback to the central nervous system and is an excellent direct measure of thyroid health. Consequently, a thyrotropin level should be drawn at the initial evaluation. When the thyrotropin is elevated, this is suggestive of hypothyroidism and should be followed with measurement of free T4 or free thyroxine index.122 When thyrotropin is abnormally low, it can be a reflection of hyperthyroidism. Further testing is required to verify this diagnosis. Prolactin
Hyperprolactinemia can cause menstrual disruption, oligomenorrhea, amenorrhea, and consequently infertility.123,124 Hyperprolactinemia is another relatively common clinical entity and can be caused by a myriad of pathologic processes. Prolactin-secreting adenomas are the most common pituitary tumor in women.125 There has been some concern in the past that prolactin evaluation after a breast examination might lead to spurious elevation since breast or nipple stimulation can markedly increase serum prolactin levels during pregnancy.126 In some patients, breast augmentation can increase serum prolactin concentrations.127 However, in the nonpregnant patient, routine breast examination does not acutely alter serum prolactin levels.128 Consequently, prolactin measurements can be drawn immediately after the initial infertility evaluation with little fear of spurious elevation. It should also be remembered that thyrotropin-releasing hormone (TRH) is a potent prolactin-stimulating substance.129 Because TRH as well as thyrotropin is elevated in hypothyroid states, prolactin secretion will also be elevated in such circumstances. To avoid confusion, thyrotropin and prolactin levels should be drawn together and under the specifications outlined here.
Cervical Factor Cervical factor accounts for approximately 5% of all clinical referrals for infertility.19 This is not surprising because the narrow cervix is the site where the greatest reduction in the number of sperm allowed to progress further into the female reproductive tract occurs. Of the 40 to 100 million sperm contained in an
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Section 6 Infertility and Recurrent Pregnancy Loss average ejaculate, only a small percentage manages to enter the uterus and proceed to the point of fertilization in the tubal ampulla. The ability of adequate number of sperm to traverse the cervix is dependent on both the diameter of the cervical os and the quantity and quality of the cervical mucus. Postcoital Test
Perhaps one of the oldest diagnostic tests for infertility is the postcoital test, first described by J. Marion Simms in 1866.130 This test for cervical factor infertility evaluates the amount and quality of cervical mucus and is usually performed 2 to 12 hours after coitus immediately before ovulation. Appropriate timing is assumed to be 24 hours after the urinary detection of an LH surge or 24 hours after intramuscular administration of human chorionic gonadotropin to induce ovulation. Performing the postcoital test either too early or too late can result in spuriously poor results. To perform a postcoital test, a vaginal speculum is placed and cervical mucus is obtained using forceps or an 18-gauge angiocatheter attached to a syringe. The mucus is evaluated for consistency, ferning, and stretchiness (spinnbarkeit) and is microscopically evaluated for number of motile sperm and cellularity. The postcoital test is no longer considered to be an important part of the infertility evaluation. One reason is that the sperm count is the only factor evaluated with a postcoital test that has been found to be predictive of pregnancy.130,131 Another reason for the fall from favor of the postcoital test is that the results rarely alter treatment decisions. If the postcoital test is repeatedly abnormal, the patient is treated with IUI, the most effective treatment for cervical factor fertility. If the postcoital test is normal, most patients are still treated with IUI, because it is also an effective treatment for unexplained infertility and improves pregnancy rates over other forms of insemination regardless of the cause of infertility.132
Androgen Excess
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The signs and symptoms of hyperandrogenism can be elicited during the initial history and physical examination. When androgen excess is suspected, the patient should be screened to exclude ovarian or adrenal tumors by measuring serum androgens. Although both of these organs produce a range of androgens, tumors should be suspected if there is a de novo or rapid evolution of clinical hyperandrogenism rather than by any particular serum androgen level. Imaging studies for androgen tumors include transvaginal ultrasonography and computed tomography or magnetic resonance imaging of the adrenals. Elevated serum testosterone or dehydroepiandrosterone sulfate is often due to polycystic ovary syndrome (see Chapter 15). Some clinicians suggest that free testosterone might be a better diagnostic measurement of hyperandrogenicity than total testosterone.133 This is because the overwhelming majority of testosterone is bound to either sex-hormone binding globulin or albumin, and the androgenic effects of testosterone are created solely by the remaining 1% free testosterone. Measuring free testosterone is not necessary because there is an excellent direct correlation between total and free testosterone levels.134 Patients with elevated total testosterone will uniformly have elevated free testosterone as well.
Nonclassic congenital adrenal hyperplasia should be considered in women with hyperandrogenism and a significant family history of subfertility or infertility. In non-Jewish white populations, 1% to 5% of hyperandrogenic women are deficient in the activity of adrenal enzymes necessary to produce cortisol, most commonly 21-hydroxylase.135 The disorder is genetic and transmitted as an autosomal recessive trait. The best screening test for nonclassic congenital adrenal hyperplasia remains measurement of 17OHprogesterone.136
The Evaluation of Ovarian Reserve The age-related decline in fertility is primarily due to the relentless and progressive diminution of oocyte quality. Not only do the number of remaining ovarian follicles decline with age, those remaining become progressively less sensitive to the gonadotropin stimulation necessary for their maturation and ovulation. There consequently comes a time in every female’s reproductive life when it becomes exceedingly difficult to achieve a pregnancy with her own oocytes. The past two decades have seen remarkable progress in the study of the mechanisms of reproductive aging. All of these studies have attempted to generally describe the relative size and quality of the remaining ovarian pool. Two of them deserve mention here. Day 3 FSH
As the quality of the remaining oocyte pool decreases, the amount of follicle-stimulating hormone (FSH) secreted by the pituitary can be expected to progressively increase to drive the failing ovary harder. An early follicular, or basal, FSH drawn on cycle day 3 can have predictive value on the possibility of fertility.137–139 When basal FSH levels are elevated, especially above 10 to 15 IU/L, success with even the most provocative therapies, including in vitro fertilization, is greatly diminished.140 Clomiphene Citrate Challenge Test
The clomiphene citrate challenge test (CCCT) is a provocative examination of endocrine dynamics that is an even more sensitive test of ovarian reserve than basal FSH measurements.141 In this test a basal FSH level is measured on day 3 of the cycle. The patient is then given clomiphene citrate, 100 mg daily on days 5 to 9. The FSH level is again measured on cycle day 10. This test is considered abnormal if either day 3 or day 10 FSH levels are greater than 10 to 15 IU/L, depending on the laboratory. The CCCT is based on the two negative feedback mechanisms for the secretion of FSH from the ovary to the central nervous system: estrogen and inhibin B. When clomiphene citrate is given to women younger than age 35, it generally induces a transient increase in gonadotropin levels, with LH rising relatively more than FSH. This is due to the inhibitory effect of the large amount of inhibin B secreted by the granulosa cells of the developing follicles.142 When clomiphene citrate is given to a woman older than age 35 or one with diminishing ovarian reserve, the smaller follicular cohort results in significantly less feedback inhibition on FSH secretion.143 In this case elevations of either the basal and/or stimulated FSH levels are indicative of poor reproductive prognosis. Even with a normal basal FSH, a patient with an abnormally high day 10 value has a poorer prognosis.
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Chapter 34 Female Infertility Other Tests for Ovarian Reserve Other tests for ovarian reserve include serum inhibin, serum antimüllerian hormone, and antral follicle counts determined by ultrasonography. The serum tests are not generally available in most laboratories. The antral follicle count determines the number of follicles between 2 and 9 mm. There is a correlation with ART success and the number of antral follicles found at baseline ultrasound. Indications for Evaluation of Ovarian Reserve
Patients should undergo some evaluation of ovarian reserve in the following situations: ● ●
● ● ● ● ● ● ●
any patient older than age 35 any patient with a significant history of ovarian trauma due to surgery, infection, or endometriosis patients with unexplained infertility of any age smokers patients with a history of chemotherapy or radiation therapy patients with a significant history of autoimmune disease those with a family history of early menopause patients who have undergone a tubal ligation patients with a previous poor response to gonadotropin stimulation
TREATMENT The approach to treatment of the infertile couple is to first treat any abnormality discovered during the evaluation as specifically as possible. Previous and subsequent chapters in this textbook address the specific treatment of male factor infertility, tubal factors, endometriosis, cervical factors, ovulation induction, intrauterine insemination, and in vitro fertilization. If pregnancy is not achieved after normalization of any problems that have been diagnosed, the standard approach is to enhance fertility in a stepwise fashion, beginning with the least expensive, lowest technology treatment and progressing as needed to the most expensive, highest technology treatment that the couple desires until pregnancy is reached or the couple decides to no longer pursue the goal of conceiving a child. The most common alternatives are to adopt a child or remain childless. The physician’s role throughout this process is to assist the couple in making the best decisions they can about treatment, considering their medical conditions, emotional states, financial situation, and ultimate goals. When the couple achieves their initial goal of conceiving and giving birth to a healthy child, the physician’s work is complete. While the couple is in the midst of this often difficult endeavor or when they are unable to attain this goal, the physician’s attendance to their emotional needs or guidance in helping them reach an alternative goal becomes paramount.
Emotional Needs These emotional needs of the infertile couple should not be underestimated. By the time they arrive for their initial medical evaluation, most couples are frustrated by their failures to conceive, afraid that they will never be able to achieve success; many are self-recriminating. They often have a need to express their feelings of frustration to the physician and ancillary staff.
To meet the emotional needs of patients, it is important to acknowledge infertility as a medical and emotional struggle with a wide variety of stressors, including physical, financial, social, and marital.144 It is also important for clinicians and staff to be both sensitive and supportive to the couple. The importance and value of both members of the couple in the family and their involvement in treatment cannot be overemphasized. If there is evidence of significant emotional distress, the physician should be ready to offer help in terms of support groups or a professional infertility counselor. In addition to local resources, there are many national support organizations that can assist couples in satisfying their emotional needs, including RESOLVE (www.resolve.org), the American Fertility Association (www.theafa.org), and the American Society of Reproductive Medicine (ASRM)(www.asrm.org).
Adoption Even in the absence of a specific pathology, couples with more than a 3-year history of infertility have an increasingly poor prognosis. It is an important part of the role of the clinician to discuss the goals and options of the couples at regular intervals, especially with couples who fail to achieve success despite extensive diagnostic and therapeutic interventions. Many such couples can reach many of their goals through adoption. There are a wide range of choices in adoption. There are social agencies, private agencies, and agencies for international adoption. Social adoption is marked by a relatively low price tag, long lines and, if a healthy white child is desired, a very long wait. Older children, children of other or mixed lineage, and children with significant needs are easier to obtain. Private adoption is more specific, far more rapid, yet far more expensive. Additionally it is not legal in all states. There are numerous international organizations seeking adoptive parents for children in the third world. Clinics are usually able to direct patients toward any of these choices.
SUMMARY It must always be remembered that there are two primary goals of infertility therapy. The first is to achieve a pregnancy that leads to the delivery of a healthy infant. The second is to achieve emotional contentment regardless of conception. Infertility is a major life crisis to most patients. Its treatment involves significant temporal, economic, and emotional costs. When therapy fails, couples will go through the same standard phases of grief resolution they do when facing a death. The treating physician must continue to evaluate the couples and their needs to deal with their ongoing emotional distress. In all cases, the ultimate goal must be to assist them in returning to a happy and successful life, with or without childbearing.
PEARLS ●
●
The actual percentages by which individual factors are found to be the primary cause of infertility vary widely between studies. However, the most common primary diagnoses include male factor, tubal factor, endometriosis, ovulatory dysfunction, and cervical factor. Fecundity rates in women at age 20 approximate 20% per cycle. Subsequently, fertility rates decrease by 4% to 8% in
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Section 6 Infertility and Recurrent Pregnancy Loss
●
●
women age 25 to 29, 15% to 19% lower by ages 30 to 34, 26% to 46% by ages 35 to 39, and 95% lower at ages 40 to 45. Proper history and physical examination is important to determine the cause of infertility. Initial screening includes evaluation for immunity to specific viruses, such as rubella and varicella, as well as screening for genetic disorders that may be specific to certain ethnic groups.
●
●
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Semen analysis, hysterosalpingography, and evaluation of ovulation with BBT or serum progesterone are the standard initial investigation for all infertility patients. An endometrial biopsy and the postcoital test are no longer considered basic tests for infertility. A test for ovarian reserve should be considered in all patients with idiopathic infertility, smokers, and patients over age 35.
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and incidence of medical complications. Mayo Clin Proc 77:29–34, 2002. Metts J: Common complications of body piercing. Lancet 361:1205–1215, 2003. Mele A, Corono R, Tosti ME, et al: Beauty treatments and risk of parenterally transmitted hepatitis: Results from the hepatitis surveillance system in Italy. Scand J Infect Dis 27:441–444, 1995. Pugpatch D, Mileno M, Rich JD: Possible transmission of human immunodeficiency virus type 1 from body piercing. Clin Infect Dis 26:767–768, 1998. Holsen DS, Hartung S, Mymel H: Prevalence of antibodies to hepatitis C and association with intravenous drug abuse and tattooing in a national prison in Norway. Eur J Clin Microbiol Infect Dis 12:673–676, 1993. American Society for Reproductive Medicine: Guidelines for oocyte donation. Fertil Steril 82:S13–S15, 2004. Modest GA, Fangman JJ: Nipple piercing and hyperprolactinemia. NEJM 347:1626–1627, 2002. Herbst AL, Bern HA (eds). Developmental effects of diethylstilbesterol (DES) in pregnancy. New York, Thieme-Stratton, 1981. American College of Obstetrics and Gynecology: Cervical cytology screening. ACOG Technology Assessment Number 2, December 2002. In ACOG: Compendium of Selected Publications. Washington, D.C., ACOG, 2005. American College of Obstetrics and Gynecology: Prevention of Rh D alloimmunization. ACOG Practice Bulletin Number 4, May 1999. In ACOG: Compendium of Selected Publications. Washington, D.C., ACOG, 2005. American College of Obstetrics and Gynecology: Primary and preventative care: Periodic assessments. Committee Opinion Number 292, November 2003. In ACOG: Compendium of Selected Publications. Washington, D.C., ACOG, 2005. Centers for Disease Control and Prevention: Control and prevention of rubella: Evaluation and management of suspected outbreaks, rubella in pregnant women, and surveillance for congenital rubella syndrome. MMWR 50, pp. 1–25, 2001. Enders G: Serodiagnosis of varicella-zoster virus infection in pregnancy and standardization of the ELISA IgG and IgM antibody tests. Dev Biol Stand 52:221–236, 1982. Harger JH, Ernest JM, Thurnan GR, et al: Frequency of congenital varicella syndrome in a prospective cohort of 347 pregnant women. Obstet Gynecol 100:260–265, 2002. Glantz JC, Mushlin AL: Cost-effectiveness of routine antenatal varicella screening. Obstet Gynecol 91:519–528, 1998. Centers for Disease Control and Prevention: Prevention of varicella: Updated recommendations of the Advisory Committee on Immunization Practices (ACIP). MMWR 48:1–23, 1999. Shields KE, Galil K, Seward J, et al: Varicella vaccine exposure during pregnancy: Data from the first 5 years of the pregnancy registry. Obstet Gynecol 98:14–19, 2001. American College of Obstetrics and Gynecology: Prenatal and preconceptual carrier screening for genetic diseases in individuals of eastern European Jewish descent. Committee Opinion Number 298, August 2004. In ACOG: Compendium of Selected Publications. Washington, D.C., ACOG, 2005. American Society for Reproductive Medicine: Appendix A: Minimal genetic screening for gamete donors. Fertil Steril 82:S22–S23, 2004. American College of Obstetrics and Gynecology: Preconception and Prenatal Carrier Screening for Cystic Fibrosis. Washington, D.C., ACOG, 2001. American Society for Reproductive Medicine: Optimal evaluation of the infertile female. A Practice Committee Report. Birmingham, Ala., ASRM, 2000. Centers for Disease Control and Prevention. Sexually transmitted diseases treatment guidelines 2002. MMWR 51:1–36, 2002. American Society for Reproductive Medicine: Guidelines for sperm donation. Fertil Steril 82:S9–S12, 2004. American Society for Reproductive Medicine: Guidelines for cryopreserved embryo donation. Fertil Steril 82:S16–S17, 2004.
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99. Fleischer AC: Sonography in Gynecology & Obstetrics: Just the Facts. New York, McGraw-Hill, 2004. 100. Timor-Tritsch IE, Rottem S (eds). Transvaginal Sonography, 2nd ed. New York, Elsevier, 1991. 101. Tanawattanacharnan S, Suwajanakorn S, Uepairojkit B, et al: Transvaginal hysterosalpino-contrast sonography (HyCoSy) compared with chromolaparoscopy. J Obstet Gynaecol Res 26:71–75, 2000. 102. Sladkevicius P, Ojha K, Campbell S, Nargund G: Three-dimensional power Doppler imaging in the assessment of fallopian tube patency. Ultrasound Obstet Gynecol 16:644–647, 2000. 103. Hurd WW, Wyckoff ET, Reynolds DB, et al: Patient rotation and resolution of unilateral cornual obstruction during hysterosalpingography. Obstet Gynecol 101:1275–1278, 2003. 104. Spring DB, Barkan HE, Pruyn SC: Potential therapeutic effects of contrast materials in hysterosalpingography: A prospective randomized clinical trial. Kaiser Permanente Infertility Work Group. Radiol 214:53–57, 2000. 105. Bates GW, Garza DE, Garza MM: Clinical manifestations of hormonal changes in the menstrual cycle. Obstet Gynecol Clin North Am 17:299–310, 1990. 106. Luciano AA, Peluso J, Koch EI, et al: Temporal relationship and reliability of the clinical, hormonal and ultrasonographic indices of ovulation in infertile women. Obstet Gynecol 75:412–416, 1990. 107. Moghissi KS: Accuracy of basal body temperature for ovulation induction. Fertil Steril 27:1415–1421, 1976. 108. Moghissi KS: Prediction and detection of ovulation. Fertil Steril 34:89–98, 1980. 109. Investigators World Health Organization Task Force: Temporal relationships between ovulation and defined changes in the concentration of plasma estradiol-17β, luteinizing hormone, follicle stimulating hormone and progesterone. Am J Obstet Gynecol 138:383–390, 1980. 110. Wathen NC, Perry L, Lilford RJ, Chard T: Interpretation of single progesterone measurement in diagnosis of anovulation and defective luteal phase: Observations on analysis of the normal range. BMJ 288:7–9, 1984. 111. Noyes RW, Hertig AT, Rock J: Dating the endometrium. Fertil Steril 1:3–25, 1950. 112. Petsos P, Chandler C, Oak M, et al: The assessment of ovulation by a combination of ultrasound and detailed serial hormone profiles in 35 women with long-standing unexplained infertility. Clin Endocrinol (Oxf) 22:739–751, 1985. 113. Daly DC, Soto-Albors C, Walters C, et al: Ultrasonographic assessment of luteinized unruptured follicle syndrome in unexplained infertility. Fertil Steril 43:62–65, 1985. 114. Miller PR, Soules MR: The usefulness of a urinary LH kit for ovulation prediction during cycles of normal women. Obstet Gynecol 87:13–17, 1996. 115. Lang-Dunlop A, Schultz R, Frank E: Interpretation of the BBT chart using the “Gap” technique compared to the colorline technique. Contraception 71:188–192, 2005. 116. Miller PB, Soules MR: The usefulness of a urinary LH kit for ovulation prediction during menstrual cycles of normal women. Obstet Gynecol 87:13–17, 1996. 117. Martinez AR, Bernardus RE, Vermeiden JP, Schoemaker J: Time schedules of intrauterine insemination after urinary luteinizing hormone surge detection and pregnancy results. Gynecol Endocrinol 8:1–5, 1994. 118. Nielsen MS, Barton SD, Hatasaka HH, Stanford JB: Comparison of several one-step home urinary hormone detection kits to OvuQuick. Fertil Steril 76:384–387, 2001. 119. Lloyd R, Coulam CB: The accuracy of urinary luteinizing hormone testing in predicting ovulation. Am J Obstet Gynecol 160:1370–1372, 1989. 120. Wentz AC: Endometrial biopsy in the evaluation of infertility. Fertil Steril 33:121–124, 1980. 121. Coutifaris C, Myers ER, Guzick DS, et al., for the NICHD National Cooperative Reproductive Medicine Network: Histological dating of timed endometrial biopsy tissue is not related to fertility status. Fertil Steril 82:1264–1272, 2004.
122. Spencer C, Eigen A, Shen D, et al: Specificity of sensitive assays of thyrotropin (TSH) used to screen for thyroid disease in hospitalized patients. Clin Chem 33:1391–1396, 1987. 123. Bohnet HG, Dahlen HG, Wutke W, Schneider HPG: Hyperprolactinemic anovulatory syndrome. J Clin Endocrinol Metab 42:132–143, 1976. 124. Moult PJA, Rees LH, Besser GM: Pulsatile gonadotropin secretion in hyperprolactinemic amenorrhoea and the response to bromocriptine therapy. Clin Endocrinol 16:153–162, 1982. 125. Yen SSC, Jaffe RB: Prolactin in human reproduction. In Yen SSC, Jaffe RB, Barbieri RL (eds). Reproductive Endocrinology: Physiology, Pathophysiology and Clinical Management, 4th ed. Philadelphia, WB Saunders, 1999, pp 273–274. 126. Hatjis CG, Morris M, Rose JC, et al: Oxytocin, vasopressin and prolactin responses associated with nipple stimulation. South Med J 82:193–196, 1989. 127. Hartmann BW, Laml T, Kirchengast S, et al: Hormonal breast augmentation: Prognostic relevance of insulin-like growth factor-I. Gynecol Endocrinol 12:123–127, 1998. 128. Hammond KR, Steinkampf MP, Boots LR, Blackwell RE: The effect of routine breast examination on serum prolactin levels. Fertil Steril 65:869–870, 1996. 129. Jacobs LS, Snyder PJ, Wilbur JF, et al: Increased serum prolactin after administration of synthetic thyrotropin releasing hormone (TRH) in man. J Clin Endocrinol Metab 33:966, 1971. 130. Glatstein IZ, Best CL, Palumbo A, et al: The reproducibility of the postcoital test: A prospective study. Obstet Gynecol 85:396–400, 1995. 131. Beltsos AN, Fisher S, Uhler ML, et al: The relationship of the postcoital test and semen characteristics to pregnancy rates in 200 presumed fertile couples. Int J Fertil Menopausal Stud 41:405–411, 1996. 132. Hurd WW, Randolph JF, Ansbacher R, et al: Comparison of intracervical, intrauterine, and intratubal techniques for donor insemination. Fertil Steril 59:339–342, 1993. 133. Loric S, Guechot J, Duron F, et al: Determination of testosterone in serum not bound by sex-hormone binding globulin: Diagnostic value in hirsute women. Clin Chem 34:1826–1829, 1988. 134. Schwartz U, Moltz L, Brotherton J, Hammerstein J: The diagnostic value of plasma free testosterone in non-tumorous and tumorous hyperandrogenism. Fertil Steril 40:66–72, 1983. 135. Azziz R, Dewailly D, Owerbach D: Clinical review 56: Non-classic adrenal hyperplasia: Current concepts. J Clin Endocrinol Metab 78:810–815, 1994. 136. American Society for Reproductive Medicine: The evaluation and treatment of androgen excess. Fertil Steril 82:S173–S180, 2004. 137. Scott RT, Toner JP, Mujasher SJ, et al: Follicle-stimulating hormone levels on cycle day 3 are predictive of in vitro fertilization outcome. Fertil Steril 51:651–654, 1989. 138. Toner JP, Philput CB, Jones GS, Muasher SJ: Basal follicle-stimulating hormone is a better predictor of in vitro fertilization performance than age. Fertil Steril 55:784–791, 1991. 139. Pearlstone AC, Fournet N, Gambone JC, et al: Ovulation induction in women over 40 and older: The importance of basal follicle-stimulating hormone level and chronological age. Fertil Steril 58:674–679, 1992. 140. Scott RT, Hofmann GE: Prognostic assessment of ovarian reserve. Fertil Steril 63:1–11, 1995. 141. Navot D, Rosenwaks Z, Margolioth EJ: Prognostic assessment of female fecundity. Lancet ii:645–647, 1987. 142. Hofmann GE, Danforth DR, Seifer DB: Inhibin-B: The physiologic basis of the clomiphene citrate challenge test for ovarian reserve screening. Fertil Steril 69:474–477, 1998. 143. Yong PY, Baird DT, Thong KJ, et al: Prospective analysis of the relationships between the ovarian follicle cohort and basal FSH concentration, the inhibin response to exogenous FSH and ovarian follicle number at different stages of the normal menstrual cycle and after pituitary down-regulation. Hum Reprod 18:35–44, 2003. 144. Burns LH, Covington SN: When Infertility Strikes The Family: Helping The System Cope. Available at http://www.resolve.org/main/ national/familyfriend/strik.jsp. Accessed
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35
Evaluation of Male Infertility Dana A. Ohl, Timothy G. Schuster, and Susanne A. Quallich
INTRODUCTION A defect in male fertility can be found in up to 50% of couples with infertility. The male is the only cause of infertility in 30% of cases, and a combination of male and female factors can be found in another 20%.1 In the past, a combination of a lack of understanding of the pathophysiology of male infertility and a paucity of successful treatment modalities often led to neglect of the male in the evaluation process. In some cases women have undergone invasive testing and treatment before evaluation of their mate, only to find on subsequent semen analysis that the male partner was the source of the couple’s infertility. In other cases, the discovery of a markedly abnormal result on semen analysis has led to the immediate application of in vitro fertilization with intracytoplasmic sperm injection (IVF/ICSI) before a full evaluation of the male partner has been undertaken. In either case, the affected couple does not receive the optimal benefit of the extensive diagnostic and treatment modalities that have been developed for male infertility over the past 20 years. This chapter begins with an examination of the basic principles of male infertility. The standard and advanced diagnostic techniques are then detailed. Finally, the various treatment modalities and their effectiveness for specific diagnoses are elucidated.
GENERAL PRINCIPLES When male infertility is discovered, it is imperative for the man to be evaluated by a male infertility specialist before attempting pregnancy for several reasons. In some conditions, treatment modalities can improve the prospects of a couple achieving pregnancy. In others, careful evaluation will determine the presence of associated medical problems.2 For some couples with male infertility, genetic testing is essential to give prognostic information as to potential success and genetic risk assessment for the potential progeny to infertile couples considering treatment.3 In those men whose evaluation does not reveal a potentially treatable condition, contact with a male infertility specialist during the evaluation process completes the team that will implement comprehensive treatment plans that might include sperm retrieval with assisted reproductive technologies (ARTs).
Treatable Causes of Male Infertility Many men with male infertility will be found to have conditions amenable to surgical or medical treatment. Varicocele surgery has become more reliable and less invasive due to introduction of improved surgical techniques, such as the microsurgical
subinguinal approach.4,5 Surgical repair of epididymal obstructions has enjoyed higher success rates with introduction of invagination techniques.6 In men with clear-cut endocrinopathies, medical treatments are highly successful in improving fertility.7
Associated Medical Problems Male infertility increases the risk of other potentially dangerous medical problems, such as testicular cancer, spinal cord and brain tumors, genitourinary malformations, and chromosome aberrations.3 Men with severe oligospermia should be fully evaluated for these conditions before being directed toward attempts at pregnancy with IVF/ICSI. Failure to evaluate the male for these problems may delay the diagnosis of these potentially dangerous conditions.
Genetic Testing In recent years, our understanding of the genetics of male infertility has markedly improved. For example, it is now standard to perform Y-chromosome microdeletion testing in men with azoospermia or severe oligospermia, because aberrations in spermatogenesis have been linked to Y-chromosome microdeletions.2 Using this approach, an underlying genetic problem can be determined in many of these men whose abnormalities would have been designated as idiopathic in the past. Another example is congenital bilateral absence of vas deferens, which accounts for up to 5% of all male infertility. It has been observed that men with cystic fibrosis uniformly have this condition, but most men with congenital bilateral absence of vas deferens do not have the pulmonary or gastrointestinal problems indicative of cystic fibrosis. Subsequent research has shown that more than half of all men with congenital bilateral absence of vas deferens have mutations in the cystic fibrosis transmembrane conductance regulator (CFTR) gene, the same gene responsible for cystic fibrosis. In these cases, congenital bilateral absence of vas deferens is considered to be an atypical form of cystic fibrosis and is inherited in an autosomal recessive pattern.
PATHOPHYSIOLOGY The list of possible causes of male infertility is extensive (Table 35-1). Causative conditions and factors can almost always be identified by a detailed history, physical examination, and semen analysis. Some of the most common causes are explored below in more detail.
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Section 6 Infertility and Recurrent Pregnancy Loss Table 35-1 Male Infertility Etiologies Ejaculation Problems Anejaculation Retrograde ejaculation Sexual dysfunction Environmental High-temperature working environments Therapy-related Chemotherapy Radiation Medications Exogenous hormones Acquired Trauma Infection Prostatitis Epididymitis Orchitis Testicular cancer Systemic disease Hypothyroidism Immunologic Malignancies Anatomic Varicocele Obstructive azoospermia Vas deferens Epididymal Ejaculatory duct Developmental and Structural Specific genetic causes Klinefelter’s syndrome Cystic fibrosis Y-chromosome microdeletions Translocations Cryptorchidism Gonadal failure (hypergonadotropic hypogonadism) Sertoli cell only syndrome Impaired sperm transport (aperistalsis of vas deferens) Sperm Defects Spermatogenetic arrest Anomalies of sperm structure Hormonal Causes and Androgen Resistance Hypogonadotropic hypogonadism Hyperprolactinemia Congenital adrenal hyperplasia Androgen resistance syndrome Idiopathic
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the inferior vena cava; and (3) the “nutcracker phenomenon,” caused by compression of the left renal vein between the superior mesenteric artery and aorta. The mechanism by which a varicocele causes impaired testicular function is poorly understood. It is well accepted that the presence of a varicocele is associated with progressive decline of testicular volume, impaired sperm quality, and loss of Leydig cell function.10 It has been shown that larger varicoceles are associated with greater impairment of testicular dysfunction compared to smaller varicoceles.11,12 Theories proposed to explain these observations include increased testicular temperature from loss of the countercurrent mechanism present in the normal spermatic cord, hypoxia, and reflux of renal or adrenal hormonal metabolites.13–15 Treatment
Several techniques exist to repair a varicocele, including surgical and radiographic intervention. These techniques are described in more detail in the subsequent chapter. Repair of a varicocele has been shown to improve spermatogenesis, increase Leydig cell function, and prevent further decline in testicular size.16–18 Many studies have evaluated the effectiveness of varicocele repair on improving pregnancy rates. However, most studies have been retrospective and poorly controlled. To date, only two randomized, prospective, case-controlled studies of varicocele have been performed. The first study randomized patients to surgical repair, radiographic embolization, or observation.19 Unfortunately, 48% of patients in this study had a grade 1 varicocele, for which repair is of questionable value. Although there was significant improvement in semen parameters in the patients receiving intervention, no difference was seen in pregnancy rates. The second study was a crossover design.20 A total of 45 couples underwent either immediate or delayed repair of a varicocele after 1 year of observation. Pregnancy rates were 60% during the first year for those undergoing immediate repair compared to 10% for those in the observation group. For the latter group, pregnancy rates increased to 44% during the subsequent year after repair.
Varicocele
Genetic Causes of Male Infertility
A varicocele is the single most commonly identified surgically treatable condition found in men with abnormal results on semen analysis. It has been reported that in asymptomatic men with a palpable varicocele, an abnormality on semen analysis will be found in 70%. A varicocele is present in approximately 35% to 40% of men with primary infertility and 80% of men with secondary infertility.8,9 However, not all men with a varicocele will be infertile, and this entity will be found in approximately 15% of all men. The majority of varicoceles will be found on the left side, but they can be either unilateral or bilateral. The etiology of a varicocele remains uncertain. The finding that more varicoceles occur on the left suggests they might be due to increased hydrostatic pressure in the internal spermatic veins. Related theories include: (1) the longer internal spermatic vein on the left compared to the right, resulting in increased hydrostatic pressure on the left; (2) the acute angle of insertion of the left internal spermatic vein into the left renal vein compared to the oblique insertion of the right internal spermatic vein into
A detailed discussion of the genetics of reproduction is given in Chapter 5. Klinefelter’s Syndrome
Klinefelter’s syndrome is a chromosomal aberration resulting in a genotype of 47,XXY in 90% of cases or the mosaic form of 46,XY/47,XXY in the remaining 10% of patients.21 Classically, men present as tall, eunuchoid appearance with azoospermia, gynecomastia, and small firm testes. However, a spectrum of presentations exists, especially in the mosaic form. Diagnosis is confirmed with a karyotype. Sperm extraction with ICSI has been reported in this patient population; however, couples should undergo preoperative counseling regarding risks of genetic transmission. Cystic Fibrosis
Cystic fibrosis is the most common autosomal recessive disorder in whites.22 It is associated with congenital bilateral absence of
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Chapter 35 Evaluation of Male Infertility the vas deferens in addition to pulmonary disease and exocrine pancreas dysfunction. Patients with this disease have mutations in the CFTR gene. This gene makes a protein responsible for chloride channel formation, and these mutations result in nonfunctioning channels. The mechanism by which these mutations result in degeneration of the developing vas deferens remains to be determined. An atypical form of cystic fibrosis should be suspected in any apparently healthy man with azoospermia and bilateral absence of the vas deferens on examination.22 More than half of these men will be found to have mutations in the CFTR gene. Because of the high carrier rate for cystic fibrosis in the population, all men with congenital bilateral absence of the vas deferens and their spouses should be screened for CFTR gene mutations. It is imperative that couples at risk for creating embryos with homozygous gene mutations for cystic fibrosis undergo genetic testing and counseling before proceeding with sperm harvesting and ICSI. Y-Chromosome Microdeletions
The long arm (q) of the Y chromosome contains three regions where mutations may lead to azoospermia or severe oligospermia. These genetic regions, termed azoospermia factors (AZF), have been subdivided into regions a, b, and c. Testing for Y-chromosome microdeletions should be considered in men with severe oligospermia or nonobstructive azoospermia. Successful pregnancies have been reported using ICSI for men with AZFc deletions; however, no patient with AZFa or AZFb deletions has been reported to have sperm on testicular biopsy.23–25 Although no somatic changes are evident in the offspring of patients with AZFc deletions, couples should be counseled that the genetic mutation will be transmitted to male progeny, who will face similar fertility issues in the future.
Ejaculatory Dysfunction Although relatively uncommon, ejaculatory dysfunction encompasses a large variety of disorders with individualized treatments. The entire spectrum of causes of ejaculatory dysfunctions cannot be covered in the scope of this chapter. However, some of the more common entities are explained here. Medications
Several classes of frequently used medications can cause ejaculatory dysfunction. The antiadrenergic properties of antihypertensives (e.g., methyldopa, doxazosin) can cause incomplete closure of the bladder neck, leading to retrograde ejaculation or in extreme cases failure of emission. Commonly used antidepressants (e.g., selective serotonin reuptake inhibitors [SSRIs]) and antipsychotics (e.g., thioridazine, clozapine) are also well-known causes of either delayed ejaculation or anejaculation.26,27 Diabetes Mellitus
Although erectile dysfunction is a more common finding in patients with diabetes mellitus, ejaculatory dysfunction may also be present due to the autonomic neuropathic effects on the sympathetic chain controlling the bladder neck. Difficulties with ejaculation or emission are present in up to 32% of diabetic patients.28
Spinal Cord Injury
Difficulties with ejaculation are reported in more than 80% of spinal cord injury patients.29 Because of the relatively young age of many of these patients, ejaculatory dysfunction represents a major cause of infertility after spinal cord injury.
Medications and Male Infertility In addition to ejaculatory dysfunction, several classes of medications can cause erectile dysfunction. Other medications can suppress germ cell function either directly or by disturbing the hypothalamic-pituitary-gonadal axis. Anabolic Steroids
Normal levels of intratesticular testosterone are essential for normal spermatogenesis, and these levels are significantly higher than peripheral testosterone levels.30 Use of anabolic steroids causes suppression of normal testicular feedback from the testes to the hypothalamus and pituitary, thus leading to decreased intratesticular testosterone levels and impaired spermatogenesis.31 Cessation of the exogenous androgens usually allows for resumption of normal spermatogenesis. However, there are case reports of continued disorders of the hypothalamic-pituitarygonadal axis after discontinuation of anabolic steroid use. Chemotherapy
Many chemotherapy agents are know to cause damage to germinal epithelium. As a general rule, the severity of gonadal toxicity is dose-dependent and is related to the class of chemotherapeutic agent used. Although some men will have recovery of spermatogenesis up to 5 years after treatment, a subset of men receiving chemotherapy will have permanent sterility.32 Before initiating chemotherapy there is currently no way to predict which men will have return of fertility. Consequently, sperm banking should be offered to all men before treatment.
EVALUATION OF THE MALE Male Partner History All evaluations of the infertile couple require a careful history from the male in addition to a semen analysis. In most infertility practices, physical examination of the male is performed only if the semen analysis is abnormal or if there is a history of some abnormality. An algorithm for the evaluation of male infertility is presented in Figure 35-1. General History
The general history of a male patient relative to the evaluation for male factor infertility should ascertain the duration of the couple’s attempts at pregnancy, if children have been born or a positive pregnancy test has occurred in this relationship or in another relationship before the current relationship, and the results of any prior semen analyses. It should be established that puberty started in the early or middle teens and was accompanied by normal physiologic male development. The clinician should also inquire about any previous evaluation and treatment for male or female factor infertility and should discuss any systemic illness within the past 6 months, particularly if it was a febrile illness.33 The review of systems should specifically include recent weight gain or loss, fevers, colds, sinus infections,
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Section 6 Infertility and Recurrent Pregnancy Loss Female evaluation Complaint of Infertility Male evaluation
Azoospermia or severe oligospermia (<5 million sperm) with bilateral vas present
Normal semen analyses
Concentrate on any female factors
Consider IUI for unexplained infertility
Low volume
Normal volume
Retrograde semen analysis
FSH, total testosterone, and consider genetic testing
If positive, refer to male infertility evaluation and treatment of retrograde ejaculation
If negative,draw FSH, total testosterone
History Physical Examination Semen analysis x 2
Azoospermia with bilateral vas absent
Normal volume Abnormal semen analysis
CFTR testing and genetic counseling and FSH test
FSH, total testosterone
Varicocele
Elevated or normal FSH Normal testosterone
Refer for male infertility evaluation and possible varicocele repair
Consider ART
Low LH, low FSH, low testosterone
Refer to male infertility for specific endocrine therapy
Refer for male infertility evaluation and possible testes biopsy Figure 35-1
Suggested algorithm for the evaluation of male infertility.
anosmia, peripheral field visual problems, breast pain or secretions, and scrotal pain. Evaluation should also include any potential exposure to environmental toxins, either through occupation or hobbies. This includes such factors as excessive heat, radiation, heavy metals, and glycol ethers or other organic solvents because these may each have an effect on spermatogenesis.34 Past Medical History
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The evaluation should then proceed to a history of any condition that would potentially affect the genitals or endocrine system. Infertility in the male can be the presenting symptom of other serious conditions, and careful evaluation is vital. Pertinent findings would include a history of cryptorchidism, significant genital trauma, previous diagnosis of varicocele, hypothyroidism, or known pituitary malfunction. It will also include a review of any additional medical conditions for which the patient is being
followed, including any condition that would require radiotherapy or chemotherapy. Diabetes, chronic obstructive pulmonary disease, sleep apnea, renal insufficiency, and hepatic insufficiency are possible contributors to male subfertility.35 Prior sexually transmitted infections can lead to obstruction of the genital ducts. Surgical History
Past surgical events of note include any genitourinary surgeries such as orchiopexy, YV plasty to the bladder neck, inguinal hernia repair, correction of epispadias or hypospadias, prostate surgery, bladder reconstructions, bladder surgeries, or testicular surgeries. Additionally, one should inquire about previous treatment for testicular or other urologic malignancies, either with surgery, chemotherapy, or radiation, and obviously previous vasectomy. The surgical history should specifically ask about procedures that may impair ejaculation due to injury to the retroperitoneal sympathetic nervous system. The most common procedure
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Chapter 35 Evaluation of Male Infertility would be retroperitoneal lymph node dissection performed for testicular carcinoma.36 Sexual and Fertility History
The history should include the overall pattern of sexual activity, specifically in relation to ovulation.37–39 One should inquire about any previously fathered children as well as any evaluation or treatment of the female partner that may have preceded the patient’s visit, such as the use of ovulation predictor kits or medications. The couple must also be asked about the use of lubricants during sexual intercourse. Many commercially available lubricants are known to impair sperm motility.40 The timing of sexual intercourse in relation to ovulation should be noted because simply adjusting the timing of intercourse can result in an increased chance for pregnancy. Recent data suggests that daily intercourse beginning 5 days before ovulation may be the best intercourse pattern to optimize the chance of pregnancy.37 Each patient should be queried regarding erectile function, ejaculation, and libido because these issues can contribute to infertility. Typically, erectile difficulties from an organic cause are insidious and progressive and may span the course of several years. Alternatively, the patient may provide a history of relatively rapid or recent onset of a decline in erectile function, which may be associated with a history of recently starting new medication or the stress of the fertility difficulties. The history should include several points specific to the patient’s sexual functioning: the precise nature of the dysfunction (i.e., whether the problem is attaining or sustaining an erection, insufficient rigidity, difficulty with penetration); the presence or absence of nocturnal and morning erections and their quality; and any treatments (pharmacologic and nonpharmacologic) that the patient has tried. In some cases, treatment of the underlying sexual dysfunction may be all that is needed to produce a successful conception. If the patient complains of low libido, moodiness, loss of interest in usual activities, declining erectile function, fatigue, and diminished muscle bulk, he may be suffering from hypogonadism. One should ask if complaints are new or longstanding. The patient should be carefully questioned about ejaculatory dysfunction, including pain with ejaculation and hematospermia. Common types of ejaculatory dysfunction include anejaculation (complete lack of ejaculation despite a normal sensation of orgasm), anorgasmia (inability to achieve climax), and retrograde ejaculation, which can appear identical to the patient to anejaculation. Anejaculation and retrograde ejaculation can be the result of a variety of surgical procedures, progressive neurologic disease, or medications.38 Anorgasmia may be psychogenic or due to medications, most notably SSRIs, commonly given for depression.39 Medication History
A careful medication history is an important part of the initial evaluation of the male presenting for evaluation of male factor infertility. The use of calcium channel blockers has been implicated in decreased sperm fertilization potential.41 Spironolactone can contribute to a decreased fertilization capacity and a decline in spermatogenesis.42 Anabolic steroid use can also result in profound decline in sperm counts.31 The patient must also be asked about the ingestion of nutriceuticals and other over-the counter medications.
Social History
Smoking, alcohol consumption, and marijuana use have all been implicated as gonadotoxins.35 A careful history of the use of these agents and other illicit drugs must be part of the male infertility evaluation. Family History
The family history should include a discussion of testicular or other urologic malignancies specifically, as well as a history of any cancers. The risk of certain cancers, such as prostate cancer, may be greatly elevated in men with a family history. A history of maternal medication use while pregnant with the patient should be noted because exposure to some medications in utero has been implicated in fertility reduction.43 The patient should be queried regarding siblings or extended family members who may have had fertility problems.
Female Partner History Although the responsibility for female fertility treatment will lie with the gynecologist, it is important to include a cursory female fertility history as part of evaluation of the male partner. Only with a female fertility perspective can minor abnormalities in the male be put into proper perspective. Also, some male patients will be referred for an evaluation before any female partner appointment, and if, for exanple, the treating physician is able to detect abnormalities of the menstrual cycle, that may lead to an early (and appropriate) referral to a female fertility specialist. The history of the patient’s partner should include previous pregnancies, menstrual cycle length, whether she has or is undergoing evaluation for fertility issues, and what sort of management has been necessary. The female history is detailed elsewhere in this book.
Physical Examination of the Male A physical examination is a necessary part of the complete evaluation of men with infertility. The examination should include a general examination with a focus on the genitalia. General Examination
The patient should be examined for age-appropriate development of male secondary sex characteristics. Gynecomastia may indicate estrogen excess. He should be examined for surgical scars of the abdomen or groin, because many individuals may not be aware of previous childhood hernia repair or orchiopexy. Physical examination may demonstrate some regression of secondary sexual characteristics, such as hair loss and possible loss of muscle bulk, which may indicate a hypogonadal state. Conversely, if general examination reveals muscle bulk out of proportion to frame size, the physician might suspect anabolic steroid abuse. Other signs might include significant acne, gynecomastia, abdominal striae, and testicular atrophy. It is important to recognize this situation, because many androgen abusers are reluctant to reveal their habit. Genitalia
Physical examination of the genitalia is of the utmost importance in the evaluation of male infertility. The location and size of the urethral meatus may reveal problems with sperm delivery, such as that seen with hypospadias.
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Section 6 Infertility and Recurrent Pregnancy Loss Palpation of the genitalia is the most important part of the male infertility physical examination. It is important to perform the scrotal examination in a warm room, to prevent scrotal muscle contraction, thus impairing the examination. The size and location of each testicle should be noted. The patient may have a testicle that is palpable in the inguinal canal or that cannot be palpated at all. Masses within the testicle may indicate the presence of a testicular tumor. Masses adjacent to the testicle may indicate cystic changes within the epididymis that may impair sperm flow. The epididymis should also be examined for the presence of induration, cysts, or masses. The process of spermatogenesis occupies the majority of the testicular volume in the normal situation. Therefore, the size of the testicle is a good indicator of the health of spermatogenesis in the patient. A normal testis volume is greater than 20 mL, and normal testis length is greater than 4 cm. Testicular size less than this would indicate a sperm production problem. The vas deferens is easily palpated on physical examination. One should never require operative exploration to make this diagnosis. It may be absent on one side, and this could indicate other ipsilateral Wolffian anomalies, such as absence of the kidney and ureter. Bilateral absence of the vas deferens on physical examination can explain azoospermia in men with CFTR mutations. One of the most important parts of the physical examination is determining the presence or absence of a varicocele. The patient should be examined in the standing position, both at rest and with Valsalva. In the standing position, the scrotum should be observed to see if the varicocele is actually visible (Fig. 35-2). These maneuvers are important in the grading of clinical varicoceles (Table 35-2). It is also important to subsequently examine the patient in the recumbent position. When supine, all dilation of testicular veins should disappear. If veins remain dilated, this may indicate the presence of retroperitoneal pathology, such as neoplasms, with the varicocele the result of arteriovenous shunting. The characteristics of a varicocele on physical examination have clinical importance. A varicocele that does not disappear in the recumbent position requires retroperitoneal imaging studies. The physician may be more inclined to repair grade 3 varicoceles, due to greater improvement seen with surgery. In adolescents, when sperm counts are not available, one might be inclined to repair a grade 3 varicocele, those with bilateral lesions, or those in which testicular atrophy is present.11,44
A
B Figure 35-2 A, Grade 3 varicocele is evident in this man when he is examined standing in the clinic. B, Intraoperative appearance of a grade 3 varicocele. Note dilated veins in the operative field. Table 35-2 Clinical Grading System for Varicocele
LABORATORY TESTING
Grade
Semen Analysis Semen analysis is the cornerstone of laboratory testing of male infertility.45 Still, much controversy exists about the absolute utility of this modality. No one would argue that severe deficiencies in sperm count such as azoospermia will have a profound effect on the ability to initiate a pregnancy. The importance of more subtle derangements is less clear. Standard Semen Definitions ●
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●
Normozoospermia (Normospermia): All spermatozoa and seminal plasma parameters are normal. Oligozoospermia (Oligospermia): Sperm concentration <20 million/mL.
●
●
●
● ●
Clinical Characteristics
Subclinical
Evident on ultrasound only
Grade 1
Palpable only when standing and with Valsalva maneuver
Grade 2
Palpable when standing at rest
Grade 3
Grossly visible when standing
Asthenozoospermia (Asthenospermia): Total motility < 25% or spermatozoa with forward progression <50%. Teratozoospermia (Teratospermia): Normal morphology <50% (or <15% Kruger strict criteria). Oligoasthenoteratozoospermia (Oligoasthenoteratospermia): Significant abnormalities of sperm concentration, motility, and morphology. Azoospermia: No spermatozoa in the ejaculate. Aspermia: No ejaculate.
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Semen should be collected by masturbation into a sterile container constructed of materials known to be nonspermicidal. Lubricants should not be used, because many contain bactericidal chemicals that also kill sperm. The use of nonspermicidal condoms is an alternative to those unable to masturbate into a container, but this is nonoptimal. Condom collection and intercourse as methods for obtaining a sperm specimen result in obvious potential for incomplete collection. There should be a standard abstinence period of 2 to 5 days between the last ejaculation and the time of the semen analysis. This represents only a standard and not necessarily an attempt to optimize all aspects of the semen analysis. For example, it is possible that a longer abstinence period would result in a higher count, but after several days of abstinence, there may be storage of sperm in the seminal vesicles and resultant lowering of sperm motility.46 Also, motility might be optimized by an abstinence period of 12 hours, but count will probably be impaired. It is important to remember that there is great variability in semen parameters within subjects over time.47 Therefore, patients should have two or three semen analyses separated by 2 to 3 weeks each to ensure that the trend over time is seen. Also, because the sperm production cycle requires 70 to 90 days, the results of an insult to sperm production or a treatment that may improve sperm production will not be seen until that period of time has elapsed. Therefore, performing a semen analysis less than 3 months after an intervention may be misleading.
The standards for the semen analysis are not based on a typical laboratory standard calculation, which generally entails determining a population mean +/− two standard deviations. Such a calculation carries little practical information. WHO criteria are based on the concept of limit of adequacy, which means the lower limit of normal is the value above which one gains no fertility advantage. Dropping below this level implies a decline in fertility based on the abnormal parameter. Men with decreased sperm concentrations need to be investigated for spermatogenic defects. Isolated sperm motility problems may be linked to antisperm antibodies, toxins in the collected specimen, or necrospermia. Complete absence of motility, despite demonstrated viability on vital stain, suggests a flagellar defect. Commonly, all parameters may be found to be abnormal, and may be linked to the presence of a varicocele, or in severe deficiencies, a genetic abnormality. Morphology
The largest variation between fertility centers is seen in the choice of morphology standards. The WHO and Kruger (or strict criteria) morphology systems have different methodologies and different normal ranges. Many fertility centers have adopted the Kruger morphology. This system was developed and tested prospectively in a cohort of couples undergoing IVF. Although fertilization rates dropped when Kruger morphology fell below 15%, the rates didn’t drop to extremely low levels until the 0% to 4% range. Many fertility centers use a value of less than 5% as evidence that ICSI is necessary during an IVF cycle.48
Normal Semen Parameters
The World Health Organization (WHO) criteria are the most commonly used in large fertility clinics (Table 35-3).45 When perusing a report from a laboratory that reports normal ranges substantially different from those criteria, one has to suspect that the laboratory may not have a great deal of experience in performing semen analysis.
Table 35-3 Normal Ranges for Semen Analysis According to the World Health Organization45 Semen Characteristics
Normal Values
Volume
≥2 mL
pH
7.2–8.0
Sperm concentration
≥20 × 106/ml
Total sperm count
≥40 × 106/ejaculate
Motility within 1 hour of ejaculation
Class a ≥25% Classes a and b ≥50%
Morphology
≥50% normal (WHO)45 ≥15% normal (Kruger strict morphology)48
WBC
<1.0 × 106/ml
Vitality
≥75% live
Immunobead test
≥10% sperm with beads
MAR test
<10% sperm with RBCs
Neutral α-glucosidase
≥20 mU/ejaculate
Total zinc
≥2.4 μmol/ejaculate
Total citric acid
≥52 μmol/ejaculate
Total acid phosphatase
≥200 U/ejaculate
Total fructose
≥13 μmol/ejaculate
Antisperm Antibody Testing Sperm antibodies contribute to male infertility in 9% to 36% of cases of infertility.49 Because the presence or absence of antibodies cannot be predicted based on history or physical examination, routine screening should be carried out on all semen analysis specimens obtained for the evaluation of infertility. Tests have been designed to determine the presence of antibodies in serum and seminal plasma and bound to sperm cells. Because of inexact correlation between these types of tests, the most useful tests are direct tests that determine the degree of antibody binding to the sperm cells. The most commonly used tests for this purpose are probably the commercially available SpermMar and the direct immunobead tests.
Endocrine Assessment Endocrinopathies can lead to male infertility. Individuals with abnormal semen parameters should have determination of total serum testosterone and follicle-stimulating hormone (FSH) levels.50 Although free (i.e., bioavailable) testosterone levels may be an important discriminator of men with peripheral hypogonadism, the relationship of these values to intratesticular testosterone is only beginning to be understood.30 Therefore, one cannot necessarily justify the more expensive and involved laboratory test. In men who are found to have a low total testosterone level, further testing should be performed. This includes determination of the serum luteinizing hormone (LH), prolactin, and estradiol levels. Estradiol may be elevated in a variety of circumstances, most notably obesity, due to conversion of peripheral testosterone into estradiol by aromatization in fatty tissue.
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Section 6 Infertility and Recurrent Pregnancy Loss The FSH level is extremely useful in differentiating men with obstructive azoospermia from those with nonobstructive azoospermia. Any elevation of FSH out of the normal range in the setting of azoospermia is suggestive of a sperm production problem. However, one must remember that some men with a production problem can also have a normal FSH level. Therefore, FSH is helpful in azoospermic men but not absolutely diagnostic. Men with extremely low levels of LH, FSH, and testosterone may have idiopathic hypogonadotropic hypogonadism (e.g., Kallmann syndrome), particularly those who have never undergone pubertal changes. However, another possibility is hypopituitarism secondary to hypothalamic or pituitary pathology. Brain scanning with computed tomography or magnetic resonance imaging is important to exclude mass lesions or empty sella syndrome. Generalized pituitary dysfunction can be investigated by checking another axis, such as thyroid hormones (free T4 and thyrotropin). If generalized hypopituitarism is documented, investigations for underlying causes (e.g., hemochromatosis) should be carried out.
Men with Klinefelter’s syndrome have been candidates for sperm retrieval from the testis, and no 47,XXY offspring have yet been produced. However, the experience to date with this patient population is minimal, and caution needs to be applied when undertaking such an endeavor. Couples who desire this approach should be informed that the risk of Klinefelter’s syndrome in the offspring is unknown. Y-chromosome microdeletion testing should be performed on all men with nonobstructive azoospermia for two reasons: genetic risk counseling and determining prognosis for sperm retrieval. It is highly likely that any male offspring produced with sperm retrieval and ICSI will exhibit the identical Y-chromosome abnormality of the father. Many couples will proceed with the treatment anyway, but they should be given the information to make an informed decision. If a deletion is found and is limited to the AZFc region, it is likely that attempts at sperm retrieval will be successful. However, current evidence suggests that if deletions are found in the AZFa or AZFb region, attempts at sperm retrieval will be futile.54 A normal karyotype and a karyotype from a variation of Y-chromosome microdeletion in an XX male are shown in Figure 35-3.
Genetic Testing Genetic testing is indicated in men with absence of the vas deferens and those with evidence of germ cell insufficiency, including small testes, elevated serum FSH levels, and sperm concentrations lower than 5 × 106/mL. Congenital Bilateral Absence of the Vas Deferens
Men with classic cystic fibrosis uniformly suffer from infertility due to absence of vas deferens.51 More than half of men with congenital bilateral absence of the vas deferens but no obvious symptoms of cystic fibrosis are likely to have a mutation of the CFTR gene. In fact, the chance of finding mutations in this patient population has increased at about the same rate as discovery of previously unrecognized mutations in the general population. Men with congenital bilateral absence of the vas deferens can initiate a pregnancy routinely with sperm retrieval coupled with IVF/ICSI. Before attempting to achieve pregnancy in these patients, it is essential to assess the genetic risk to the potential offspring, because these men are likely to have two abnormal copies of the CFTR gene. With a carrier rate in the white population of a CFTR gene mutation of approximately 4%, genotyping of both the patient and partner is essential to minimize the risk of having a child with cystic fibrosis.52 Whether or not the female partner is found to be a carrier, the patients can be apprised of the risk of having a child with congenital bilateral absence of the vas deferens or cystic fibrosis, as well as the implications of carrier status in the children. Severe Oligospermia
532
Karyotyping should be performed in men with azoospermia or severe oligospermia (sperm concentrations <5 × 106/mL).53 The most common karyotypic abnormality that will be found in these patients is Klinefelter’s syndrome (47,XXY), but other aberrations of sex chromosomes may be seen as well. Although the role of autosomes in controlling sperm production is unclear, Robertsonian translocations may also be seen. In recurrent miscarriage, a balanced translocation may be present in the father, which becomes unbalanced in the embryo.
IMAGING STUDIES Scrotal Ultrasound A scrotal ultrasound may be used as an adjunct to physical examination in assessing testicular or other scrotal masses. Scrotal ultrasound may also be used to measure testicular size or confirm testicular or paratesticular masses or cysts suspected by physical examination. The presence or absence of the vas deferens can be confirmed by physical examination alone and should not require ultrasound. In patients with unilateral absence of the vas deferens, consideration should be given to obtaining a renal ultrasound or intravenous pyelogram to evaluate the ipsilateral kidney because there is a strong correlation with renal anomalies in these patients.55 Although the diagnosis of varicocele is made by physical examination, in select patients ultrasound may aid in diagnosis. Various criteria have been used to define varicocele on ultrasound. Some authors have used a 2 to 3 mm diameter of any scrotal vein as diagnostic; others have suggested that the definition include the presence of three or more veins with at least one 3 mm in diameter at rest.56,57 Additionally, reversal of blood flow on Doppler ultrasound during Valsalva maneuver has also been used by clinicians for diagnosis. An ultrasound of a man with a clinical varicocele is shown in Figure 35-4. Although there are some reports of the utility of ultrasound in the diagnosis of varicocele, the usefulness of this approach remains controversial. Problems with ultrasound diagnosis of varicocele include variability in interpretation and lack of standards in determining what constitutes a varicocele on ultrasound. Furthermore, recent reports have suggested that the subclinical varicocele (a varicocele diagnosed only by ultrasound and not evident on physical examination) is not a true clinical entity. One study found that men with subclinical varicocele did not have improved semen parameters after varicocele surgery, in contrast to those with varicoceles diagnosed by physical examination.21
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A
B Figure 35-3 A, Normal 46,XY male karyotype. B, Karyotype from a 46,XX male. All autosomes are normal, but the Y chromosome is missing, and there is extra genetic material on the second X chromosome, suggesting translocation of Y chromosome material. continued
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C Figure 35-3 cont’d C, Fluorescent in situ hybridization showing the translocation of the SRY gene (red) to the X chromosome (marked green). This man’s SRY gene coded for testicular development, but the absence of the entire AZF region results in no spermatogenesis.
Figure 35-4 Scrotal ultrasound in man with a clinical varicocele, showing obvious dilated veins.
Vasogram
534
A vasogram is accomplished by injecting X-ray contrast medium through the vas deferens lumen and monitoring the flow via fluoroscopy or plain films. The purpose is to localize a site of obstruction to sperm flow. This is a test that should be performed only at the time of definitive repair of the lesion. All too commonly, vasogram is performed by nonspecialists at the time of a testis biopsy, opening up the possibility of creating a second site of obstruction due to scarring at the vasogram site. This problem is prevented by performing the vasogram only at the time of definitive reconstruction. A vasogram in a man with ejaculatory duct obstruction is shown in Figure 35-5.
Figure 35-5 Intraoperative vasogram showing ejaculatory duct obstruction. The ejaculatory ducts are entering into a large urticular cyst. This test should be performed at the time of definitive repair.
Transrectal Ultrasound A transrectal ultrasound has an important role in the evaluation of male infertility. In men with low semen volume and azoospermia, complete obstruction of the ejaculatory ducts may be found. The unobstructed ejaculatory duct typically is 4 to 8 mm in diameter and can be difficult to image,58 but in the presence of obstruction, one may find dilation of the seminal vesicles (>15 mm anteroposterior diameter), midline calcifications, or müllerian or Wolffian duct cysts (Fig. 35-6).
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A A
B Figure 35-7 A, Normal testis biopsy. B, Testis biopsy in man with Klinefelter’s syndrome, exhibiting total lack of germ cells and Leydig cell hyperplasia.
B Figure 35-6 A, Midline cyst seen on transrectal ultrasound, causing ejaculatory duct obstruction. B, After transurethral unroofing of the cyst, the entry of the ejaculatory ducts into the cyst can be seen.
Similar findings may be seen in partial ejaculatory duct obstruction, suspected in men with low semen volume and variable aberrations on semen analysis short of frank azoospermia. Transrectal ultrasound may also be helpful in men suspected of having a vas deferens abnormality, but in whom the physical examination is equivocal (an uncommon event—usually the vas deferens are present or absent). In those men, there may be unilateral or bilateral atresia of the seminal vesicles.
TREATMENT OF MALE INFERTILITY Interventional Procedures Intrauterine insemination is often used to treat mild male factor infertility (see Chapter 36). Details of specific surgical procedures
used to treat male infertility are found in Chapter 53. The following are specialized interventional procedures that can be used in selective cases for diagnosis or therapy. Testis Biopsy
The role of testis biopsy has been changing with the success of sperm acquisition and ARTs in the treatment of nonobstructive azoospermia.59 However, there still remains a role for diagnostic biopsy in the assessment of azoospermia. Diagnostic testis biopsy is indicated in men who have azoospermia but conflicting information as to whether it is obstructive or nonobstructive. Men with a clear clinical picture of small-volume testes, elevated serum FSH, and azoospermia do not require a biopsy to determine that they have a sperm production problem. However, in men with conflicting information, it may be helpful. An example might be a man with testis volume of 20 mL, an FSH near the upper limit of normal, and azoospermia. The goal of a biopsy in this man would be to determine if sperm production is normal, indicating that an obstruction may be present that might be remediable by surgical intervention. Figure 35-7 shows the contrast between a normal biopsy and that of a man with Sertoli-cell-only syndrome.
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Section 6 Infertility and Recurrent Pregnancy Loss In men with a diagnosis of germ cell deficiency, biopsy is generally used as a therapeutic procedure. The primary purpose of the biopsy is to obtain sperm for IVF/ICSI. Seminal Vesicle Aspiration
A seminal vesicle aspiration has been suggested to be an adjunctive procedure to ultrasound in the diagnosis of ejaculatory duct obstruction. In his evaluation of normal men, Jarow60 found that the postejaculatory seminal vesicle aspirates were devoid of sperm. It was not until the ejaculatory abstinence time reached 5 days that sperm were stored in the seminal vesicles. His finding of large numbers of sperm in the seminal vesicle fluid after ejaculation in men with ejaculatory duct obstruction led him to conclude that postejaculation examination of seminal vesicle aspirates (>10 sperm per unspun high power field) may be a better discriminator of ejaculatory duct obstruction than simple measurements of seminal vesicle diameters.60 Because men will accumulate sperm normally after long periods of ejaculatory abstinence, this test can also be used to give indirect evidence of unilateral vas deferens obstruction. We have arbitrarily suggested an abstinence time of 3 weeks. An aspirate of the seminal vesicles showing no sperm on one side with an abundance of sperm on the other side suggests obstruction on the former side.61 Ejaculation Induction
In anejaculatory men who fail medical management, one can entertain the possibility of ejaculation induction procedures, including electroejaculation and penile vibratory stimulation.38 The patients who benefit most commonly from this approach are patients with spinal cord injuries, because less than 20% of them will maintain ejaculatory function. The process of electroejaculation involves insertion of a probe into the rectum and application of current to produce erection and ejaculation. This procedure cannot be performed if there is any internal irritation to the rectum. For penile vibratory stimulation, a vibrator is applied to the penis to produce ejaculation. Both procedures are well-tolerated by patients with spinal cord injury. Most patients do not complain of pain with either of the procedures but do report cramping or tightening of the stomach. Blood pressure is monitored throughout the procedure, and some patients require a single dose of medication to prevent their blood pressure from rising. Anesthesia is required in some cases. Semen obtained from spinal cord-injured men by these methods often exhibits relatively poor quality. For this reason, the specimens thus obtained are often used for intrauterine insemination or IVF/ICSI.
in semen parameters, as is the case when hypothyroidism is treated with levothyroxine. Hyperprolactinemia secondary to a pituitary adenoma can often be successfully treated with a dopamine agonist such as bromocriptine. It is important to point out that therapeutic administration of testosterone to treat a hormone deficiency decreases sperm production by increasing negative feedback at the level of the hypothalamus, analogous to anabolic steroids. Empiric Clomiphene Citrate
To boost testosterone levels in the subfertile male, the synthetic antiestrogen clomiphene citrate can be given orally, usually at a dose of 25 mg daily. Clomiphene increases production of both testosterone and sperm by blocking feedback inhibition at the hypothalamic level, thus resulting in an increase in FSH and LH. Several uncontrolled studies appear to show a benefit of empiric clomiphene for the treatment of male infertility. However, a controlled trial in 23 men showed that although clomiphene citrate therapy resulted in increased levels of LH, FSH, and testosterone, there was no difference between placebo and clomiphene citrate in terms of either semen parameters or pregnancy rates.62 Sympathomimetics
If there is an issue with retrograde or low-volume ejaculation, a trial of sympathomimetics can be useful. The goal of this therapy is to convert the retrograde ejaculation to antegrade or partially antegrade ejaculation. A variety of medications, such as the alpha1-adrenergic agonist methoxamine, have been used with varying degrees of success.38 This approach is more successful with a progressive decline in function, such as seen with neurologic disease, than with the abrupt onset seen as a result of surgery. L-carnitine
Use of L-carnitine has been proposed as a supplement that can improve sperm motility and count. However, its use remains unproven. Although carnitine may have a role in the maturation of sperm, the trials to evaluate its utility in treating male factor infertility have methodological problems, and more work needs to be done.63
PEARLS ●
●
Medical Therapy
536
Medical management of male infertility assumes that there has been a specific contributing factor identified that is potentially amenable to attempts at medical treatment, most often hormonal in nature. An example would be in the case of hypogonadotropic hypogonadism, where hormonal treatment with human menopausal gonadotropins (FSH and LH) is usually successful. In the case of specific hormone deficiencies, administration of the deficient hormones or their analogues can lead to improvements
●
●
The male factor is the primary cause of infertility in 30% of infertile couples and a contributing cause in an additional 20%. The male with an abnormal semen analysis should be thoroughly evaluated for several important reasons: (1) there is a link between some causes of infertility and dangerous medical conditions; (2) the potential genetic basis of male infertility requires accurate diagnosis and genetic counseling; (3) some causes of male infertility can be successfully treated, supplanting the need for ART; and (4) this may enable optimization of the ART process in men deemed untreatable. The basic evaluation for male infertility consists of a history, physical examination, and two consistent semen analyses. Other laboratory tests are adjuncts to the basic evaluation. Men with azoospermia and severe oligospermia should undergo genetic testing, including karyotyping and Y-chromosome microdeletion testing.
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●
●
Testis biopsy can be both diagnostic and therapeutic. Transrectal ultrasound is often useful in the diagnosis of male infertility. Varicocele is the most common contributing etiology of male infertility. Although controversial, there is evidence to support varicocele treatment. Scrotal ultrasound for diagnosis of varicocele has a limited role. If a varicocele is not clinically evident, it may not need to be treated.
●
●
Men with congenital bilateral absence of the vas deferens have mutations of the cystic fibrosis gene in more than half of the cases. Before treatment, assessment of risk of cystic fibrosis in the offsping must be determined. Men with deletions of the AZFa and AZFb regions of the Y chromosome never produce sperm. Men with AZFc deletions are likely to have sperm obtained by testicular sperm extraction.
REFERENCES 1. Macleod J: Semen quality in 1000 men of known fertility and 800 cases of infertile marriages. Fertil Steril 62:862–868, 1994. 2. Pryor JL, Kent-First M, Muallem A, et al: Microdeletions in the Y chromosome of infertile men. NEJM 336:534–539, 1997. 3. Jarow JP: Life-threatening conditions associated with male infertility. Urol Clin North Am 21:409–415, 1994. 4. Goldstein M, Gilbert BR, Dicker AP, et al: Microsurgical inguinal varicocelectomy with delivery of the testis: An artery and lymphatic sparing technique. J Urol 148:1808–1811, 1992. 5. Marmar JL, Kim Y: Subinguinal microsurgical varicocelectomy: A technical critique and statistical analysis of semen and pregnancy data. J Urol 152:1127–1132, 1994. 6. Berger RE: Triangulation end-to-side vasoepididymostomy. J Urol 159:1951–1953, 1998. 7. European Metrodin HP Study Group: Efficacy and safety of highly purified urinary follicle-stimulating hormone with human chorionic gonadotropin for treating men with isolated hypogonadotropic hypogonadism. Fertil Steril 70:256–262, 1998. 8. Gorelick JI, Goldstein M: Loss of fertility in men with varicocele. Fertil Steril 59:613–616, 1993. 9. Witt MA, Lipshultz LI: Varicocele: A progressive or static lesion? Urology 42:541–543, 1993. 10. World Health Organization: The influence of varicocele on parameters of fertility in a large group of men presenting to infertility clinics. Fertil Steril 57:1289–1293, 1992. 11. Jarow JP, Ogle SR, Eskew LA: Seminal improvement following repair of ultrasound detected subclinical varicoceles. J Urol 155:1287–1290, 1996. 12. Steckel J, Dicker AP, Goldstein M: Relationship between varicocele size and response to microsurgical ligation of the spermatic veins. J Urol 149:769–771, 1993. 13. Zorgniotti AW, MacLeod J: Studies in temperature, human semen quality, and varicocele. Fertil Steril 24:854–863, 1973. 14. Tanji N, Tanji K, Hiruma S, et al: Histochemical study of human cremaster in varicocele patients. Arch Androl 45:197–202, 2000. 15. Ozbek E, Yurekli M, Soylu A, et al: The role of adrenomedullin in varicocele and impotence. BJU Int 86:694–698, 2000. 16. Kass EJ, Chandra RS, Belman AB: Testicular histology in the adolescent with a varicocele. Pediatrics 79:996–998, 1987. 17. Su LM, Goldstein M, Schlegel PN: The effect of varicocelectomy on serum testosterone levels in infertile men with varicoceles. J Urol 154:1752–1755, 1995. 18. Dubin L, Amelar RD: Varicocelectomy: 986 cases in a 12 year study. Urology 10:446–449, 1977. 19. Nieschlag E, Hertle L, Fischedick A, et al: Update on treatment of varicocele: Counseling as effective as occlusion on the vena spermatica. Hum Reprod 13:2147–2150, 1998. 20. Madgar I, Weissenberg R, Lunenfeld B, et al: Controlled trial of high spermatic vein ligation for varicocele in infertile men. Fertil Steril 63:120–124, 1995. 21. Jaffe T, Oates RD: Genetic abnormalities and reproductive failure. Urol Clin North Am 21:389–408, 1994. 22. Phillipson G: Cystic fibrosis and reproduction. Reprod Fertil Dev 10:113–119, 1998.
23. Mulhall JP, Reijo R, Alagappan R, et al: Azoospermic men with deletion of the DAZ gene cluster are capable of completing spermatogenesis: Fertilization, normal embryonic development and pregnancy occur when retrieved testicular spermatozoa are used for intracytoplasmic sperm injection. Hum Reprod 12:503–508, 1997. 24. Oates RD, Silber S, Brown LG, Page DC: Clinical characterization of 42 oligospermic or azoospermic men with microdeletion of the AZFc region of the Y chromosome, and 18 children conceived via ICSI. Hum Reprod 17:2813–2824, 2002. 25. Page DC, Silber S, Brown LG: Men with infertility caused by AZFc deletion can produce sons by intracytoplasmic sperm injection, but are likely to transmit the deletion and infertility. Hum Reprod 14:1722–1726, 1999. 26. Hendry WF: Disorders of ejaculation: Congenital, acquired and functional. Br J Urol 82:331–341, 1998. 27. Waldinger MD, Hengeveld MW, Zwinderman AH, Olivier B: Effect of SSRI antidepressants on ejaculation: A double-blind, randomized, placebo-controlled study with fluoxetine, fluvoxamine, paroxetine, and sertraline. J Clin Psychopharmacol 18:274–281, 1998. 28. Dunsmuir WD, Holmes SA: The aetiology and management of erectile, ejaculatory, and fertility problems in men with diabetes mellitus. Diabet Med 13:700–708, 1996. 29. Griffith ER, Tomko MA, Timms RJ: Sexual function in spinal cordinjured patients: A review. Arch Phys Med Rehabil 54:539–543, 1973. 30. Jarow JP, Wright WW, Brown TR, et al: Bioactivity of androgens within the testes and serum of normal men. J Androl 26:343–348, 2005. 31. Knuth UA, Maniera H, Nieschlag E: Anabolic steroids and semen parameters in body builders. Fertil Steril 52:1041–1047, 1989. 32. Howell SJ, Shalet SM: Testicular function following chemotherapy. Hum Reprod Update 7:363–369, 2001. 33. Carlsen E, Andersson AM, Petersen JH, Skakkebaek NE: History of febrile illness and variation in semen quality. Hum Reprod 18:2089–2092, 2003. 34. Sheiner EK, Sheiner E, Hammel RD, et al: Effect of occupational exposures on male fertility: Literature review. Indust Health 41:55–62, 2003. 35. Burrows PJ, Schrepferman CG, Lipshultz LI: Comprehensive office evaluation in the new millennium. Urol Clin North Am 29:873–894, 2002. 36. Ohl DA, Denil J, Bennett CJ, et al: Electroejaculation following retroperitoneal lymphadenectomy. J Urol 145:980–983, 1991. 37. Wilcox AJ, Weinberg CR, Baird DD: Timing of sexual intercourse in relation to ovulation. Effects on the probability of conception, survival of the pregnancy, and sex of the baby. NEJM 333:1517–1521, 1995. 38. Schuster TG, Ohl DA: Diagnosis and treatment of ejaculatory dysfunction. Urol Clin North Am 29(4):939–948, 2002. 39. Rosen RC, Lane RM, Menza M: Effects of SSRIs on sexual function: A critical review. J Clin Psychopharmacol 19:67–85, 1999. 40. Kutteh WH, Chao CH, Ritter JO, Byrd W: Vaginal lubricants for the infertile couple: Effect on sperm activity. Int J Fertil Menopausal Studies 41:400–404, 1996. 41. Hershlag A, Cooper GW, Benoff S: Pregnancy following discontinuation of a calcium channel blocker in the male partner. Hum Reprod 10:599–606, 1995.
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Section 6 Infertility and Recurrent Pregnancy Loss 42. Brugh VM, Matschke HM, Lipshultz LI: Male factor infertility. Endocrinol Metab Clin North Am 32:689–707, 2003. 43. Stillman RJ: In utero exposure to diethylstilbestrol: Adverse effects on the reproductive tract and reproductive performance and male and female offspring. Am J Obstet Gynecol 142:905–921, 1982. 44. Sigman M, Jarow JP: Ipsilateral testicular hypotrophy is associated with decreased sperm counts in infertile men with varicoceles. J Urol 158:605–607, 1997. 45. World Health Organization: WHO Laboratory Manual for the Examination of Human Semen and Sperm–Cervical Mucus Interaction. Cambridge, Cambridge University Press, 1999. 46. Jarow JP: Seminal vesicle aspiration of fertile men. J Urol 156:1005–1007, 1996. 47. Mallidis C, Howard EJ, Baker HW: Variation of semen quality in normal men. Int J Androl 14:99–107, 1991. 48. Grow DR, Oehninger S, Seltman HJ, et al: Sperm morphology as diagnosed by strict criteria: Probing the impact of teratozoospermia on fertilization rate and pregnancy outcome in a large in vitro fertilization population. Fertil Steril 62:559–567, 1994. 49. Ohl DA. Naz RK. Infertility due to antisperm antibodies. Urology 46:591–602, 1995. 50. Sharlip ID, Jarow JP, Belker AM, et al: Best practice policies for male infertility. Fertil Steril 77:873–882, 2002. 51. Sokol RZ: Infertility in men with cystic fibrosis. Curr Opin Pulmon Med 7:421–426, 2001. 52. Gregg AR, Simpson JL: Genetic screening for cystic fibrosis. Obstet Gynecol Clin North Am 29:329–340, 2002.
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53. Vicdan A, Vicdan K, Gunalp S, et al: Genetic aspects of human male infertility: The frequency of chromosomal abnormalities and Y chromosome microdeletions in severe male factor infertility. Eur J Obstet Gynecol Reprod Biol 117:49–54, 2004. 54. Hopps CV, Mielnik A, Goldstein M, et al: Detection of sperm in men with Y chromosome microdeletions of the AZFa, AZFb and AZFc regions. Hum Reprod 18:1660–1665, 2003. 55. Schlegel PN, Shin D, Goldstein M: Urogenital anomalies in men with congenital absence of the vas deferens. J Urol 155:1644–1648, 1996. 56. McClure RD, Khoo D, Jarvi K, Hricak H: Subclinical varicocele: The effectiveness of varicocelectomy. J Urol 145:789–791, 1991. 57. Gonda RL Jr, Karo JJ, Forte RA, O’Donnell KT: Diagnosis of subclinical varicocele in infertility. AJR 148:71–75, 1987. 58. Pryor JP, Hendry WF: Ejaculatory duct obstruction in subfertile males: Analysis of 87 patients. Fertil Steril 56:725–730, 1991. 59. Chan PT, Schlegel PN: Diagnostic and therapeutic testis biopsy. Curr Urol Rep 1:266–272, 2000. 60. Jarow JP: Diagnosis and management of ejaculatory duct obstruction. Tech Urol 2:79–85, 1996. 61. Seifman BD, Ohl DA, Jarow JP, Menge AC: Unilateral obstruction of the vas deferens diagnosed by seminal vesicle aspiration. Tech Urol 5:113–115, 1999. 62. Sokol RZ, Steiner BS, Bustillo M, et al: A controlled comparison of the efficacy of clomiphene citrate in male infertility. Fertil Steril 49:865–870, 1988. 63. Siddiq FM, Sigman M: A new look at the medical management of infertility. Urol Clin North Am 29:949–963, 2002.
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Section 6 Infertility and Recurrent Pregnancy Loss Chapter
36
Artificial Insemination Ashok Agarwal and Shyam S. R. Allamaneni
INTRODUCTION Artificial insemination is an assisted conception method that can be used to alleviate infertility in selected couples. The rationale behind the use of artificial insemination is to increase the gamete density near the site of fertilization.1 The effectiveness of artificial insemination has been clearly established in specific subsets of infertile patients such as those with idiopathic infertility, infertility related to a cervical factor, or a mild male factor infertility (Table 36-1).2,3 An accepted advantage of artificial insemination is that it is generally less expensive and invasive than other assisted reproductive technology (ART) procedures.4 This chapter provides a comprehensive description of indications for artificial insemination, issues to consider before donor insemination, complications associated with intrauterine insemination (IUI), factors affecting the success of artificial insemination, and the current evidence available on effectiveness of artificial insemination for different indications.
HISTORY Artificial insemination has been used in clinical medicine for more than 200 years for the treatment of infertile couples. In 1785 John Hunter, a Scottish surgeon from London, advised a man with hypospadias to collect his semen and have his wife inject it into her vagina. This was the first documented case of successful artificial insemination in a human. In the second half of the nineteenth century, numerous reports were published of human artificial insemination in France, England, Germany, and the United States. In 1909, the first account of successful donor artificial insemination was published in the United States. By 1949, improved methods of freezing and thawing sperm were being reported. Today, artificial insemination is frequently used in the treatment of couples with various causes of infertility, including ovulatory dysfunction, cervical factor infertility, and unexplained infertility as well as those with infertility caused by endometriosis, male, and immunologic factors. Artificial insemination with donor semen has become a well-accepted method of conception.
widely available, the terms homologous artificial insemination and heterologous artificial insemination were used to differentiate these two alternative sources. However, the use of these biomedical terms in this manner is at variance with their scientific meaning, where they denote different species or organisms (as in, e.g., homologous and heterologous tissue grafts). In the latter half of the 20th century, the terms artificial insemination, donor (AID) and artificial insemination, husband (AIH) found common use. However, the widespread use of the acronym AIDS for acquired immunodeficiency syndrome resulted in the replacement of AID with therapeutic donor insemination (TDI). An analogous alternative term for AIH has not evolved, probably in part because of the increasingly common situation where the woman’s partner is not her legal husband. In this chapter, artificial insemination using these two standard sperm sources will be designated simply as partner and donor insemination.
Techniques Several different techniques have been used for artificial insemination. The original technique used for over a century was intravaginal insemination, where an unprocessed semen sample is placed high in the vagina. In the latter half of the 20th century, the cervical cap was developed to maintain the highest concentration of semen at the external os of the cervix. It was soon discovered that placing the semen sample into the endocervix (intracervical insemination) resulted in pregnancy rates similar to that obtainable using a cervical cap and superior to those seen with high vaginal insemination.5
Intrauterine Versus Intracervical Insemination A major breakthrough came in the 1960s when methods were developed for extracting enriched samples of motile sperm from semen. These purified samples were free of proteins and prostaglandins, and thus could be placed within the uterus using a technique designated intrauterine insemination (IUI). This Table 36-1 Infertility Disorders with Proven Benefit from Partner Insemination
GENERAL CONSIDERATIONS Idiopathic infertility
Semen Sources The source of semen for artificial insemination can be either from the woman’s male partner or from a donor, who usually remains anonymous. When donor insemination first became
Cervical factor infertility Mild male factor infertility From Cohlen BJ: Should we continue performing intrauterine inseminations in the year 2004? Gynecol Obstet Invest 59:3–13, 2004.
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Section 6 Infertility and Recurrent Pregnancy Loss technique was found to result in pregnancy rates 2 to 3 times those of intracervical insemination. However, intracervical insemination is still utilized in some practices.5 In an effort to further improve pregnancy rates, techniques were developed to place washed sperm samples directly into the tubes via transcerival cannulation (intratubal insemination) or into the peritoneal cavity via a needle placed through the posterior cul-de-sac (intraperitoneal insemination). Another technique developed in Europe, termed fallopian tube sperm perfusion, involves pressure injection of a large volume (4 mL) of washed sperm sample while the cervix is sealed to prevent reflux of the sample.6 This technique appears to have a higher pregnancy rate than IUI in couples with unexplained infertility. The remainder of these technically difficult approaches have never been shown to result in better pregnancy rates than IUI. One prospective, randomized study found that simultaneous intratubal insemination actually decreased the pregnancy rates associated with IUI.7 In modern clinical practice in the United States, IUI is the predominant technique used for artificial insemination.
EVALUATION Male Evaluation Semen Analysis
The male partner is initially evaluated by obtaining a complete semen analysis and screen for sperm antibodies. A minimum of two samples provided over 1 to 2 months is analyzed. A third sample may be required if there is a discrepancy between the initial samples. All samples should be provided after 48 to 72 hours of sexual abstinence. Samples should be analyzed within 2 hours of collection. Antisperm Antibodies
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Male antisperm antibodies are found in approximately 10% of semen samples from infertile couples. Men with antisperm antibodies attached to their sperm are classified as having immunologic infertility. These antibodies are believed to decrease fertility by inducing agglutination or immobilization of the sperm. Studies have identified multiple antisperm antibodies that correspond to a variety of sperm components. There are multiple known risk factors for the development of male antisperm antibodies.8 Vasectomy results in the development of antisperm antibodies in the majority of men. After successful vasovasostomy, more than half of these men will have detectable sperm-bound antibodies. The pregnancy rates will depend on many factors, including the titer and quantity of gross agglutination. Obstructive azospermia from any cause (e.g., congenital absence of the vas deferens, cystic fibrosis, infant hernia repair) increases the risk of antisperm antibodies. Reproductive infections (e.g., epididymitis, prostatitis, or orchitis) are also associated with antisperm antibodies. Antisperm antibody tests are performed as a routine part of a complete semen analysis during the initial infertility evaluation. The most commonly used test in clinical practice is probably the immunobead assay.8 This quantitative assay evaluates live sperm and indicates percent bound, antibody isotype, and binding location. For routine screening, some andrology laboratories use a commercially available mixed antiglobulin reaction assay (SpermMar).
Male subfertility is significantly increased when the antisperm antibody level is greater than 50%.9,10 Antisperm antibodies interfere with sperm–zona pellucida binding and prevent embryo cleavage and early development. Complete Evaluation
In the presence of persistently abnormal results on semen analysis, a complete history, physical examination, and laboratory evaluation is performed to find and treat any potentially reversible abnormalities (see Chapter 35).
Female Evaluation The female partner should undergo a basic infertility evaluation so that any correctable factors can be identified and treated before artificial insemination (see Chapter 34). In addition to a detailed history and physical examination, each woman considering partner or donor insemination should be evaluated with an imaging technique, usually a hysterosalpingogram, to document patent tubes. Unless oral or injectable medications are used to induce superovulation, ovulatory function should be evaluated with a urinary luteinizing hormone (LH) detection kit and midluteal serum progesterone level. Further evaluation is required in the event of detection of any clinical or laboratory abnormalities. In the past, a great deal of time was spent investigating the possibility of cervical factor infertility by evaluating the character and sperm survivability in periovulatory cervical mucus, using what is termed a postcoital test. This test had many false-positive results, because it depended more on timing in the cycle and hormonal status than on static cervical characteristics. Except for exclusion of cervicitis during pelvic examination, timed evaluation of cervical mucus and sperm interaction is infrequently included in a fertility examination. This is because partner IUI is used as a basic fertility enhancement method for the majority of couples who have otherwise been unable to conceive regardless of diagnosis.
INDICATIONS Partner Insemination Partner insemination was originally developed as a treatment for male factor infertility. With the advent of IUI, partner insemination has been found to be an excellent treatment for a range of diagnoses, including cervical factor infertility, unexplained infertility, and subfertility, on the basis of other diagnoses or therapeutic measures (Table 36-2). This ability of partner insemination to increase pregnancy rates regardless of diagnosis has made this technique one of the fundamental approaches to infertility treatment today. Male Factor Infertility
Partner insemination appears to be of clear benefit when the couple’s infertility is the result of any condition that makes it difficult to place semen high in the vagina during coitus. Male conditions resulting in this situation are termed ejaculatory failure. The most common causes of ejaculatory failure are impotence, severe hypospadias, and retrograde ejaculation. A unique condition that has been found to be treatable with artificial insemination is impotence secondary to spinal cord injury.11
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Chapter 36 Artificial Insemination Table 36-2 Indications and Contraindications for Partner Insemination Indications
Contraindications
Male Factor Infertility
Absolute Contraindications
Disorders of semen density, motility, and morphology (mild oligospermia, asthenozoospermia, teratozoospermia) Immunologic factors Ejaculatory failure Mechanical factors (malformed urethra, hypospadias)
Rh blood factor incompatibility Medical conditions that could endanger the patient’s life A partner with hereditable disease Cervical neoplasia Blocked tubes Active genital tract infection in either partner
Female Factor Infertility
Relative Contraindications
Cervical factor Vaginismus Mild endometriosis Ovulatory dysfunction
Severely abnormal semen parameters Multiple failures at previous partner insemination attempts Recent chemotherapy or radiotherapy Coexisting multiple infertility etiologies Pelvic surgery Older age woman
Unexplained Fertility
An Adjunct to Other Infertility Treatments
Partner IUI appears to be of value for increasing per cycle fecundity when inducing ovulation in women with ovulatory dysfunction.13 After ovulation induction with clomiphene citrate, partner IUI might work by overcoming the decreased cervical mucus associated with the use of clomiphene.14 With gonadotropins, partner IUI might compensate for subtle changes in sperm transport within the uterus or tubes related to marked alterations in circulating estrogen and progesterone levels associated with their use. Partner IUI also appears to be of some benefit when women with mild and minimal endometriosis are trying to achieve pregnancy. After appropriate surgical treatment, the monthly improvement in fecundity with partner IUI appears to be similar to that seen in patients with idiopathic infertility.15 Women with severe endometriosis or tubal disease have a far lower fecundity rate and often an increased rate of ectopic pregnancies. For this reason, these patients appear to benefit more from IVF than from partner IUI combined with superovulation. Unexplained Infertility
Partner insemination is also commonly used as a treatment for male factor infertility documented by repeated abnormal results on semen analysis. In couples where there is mild male factor infertility, defined as a progressive sperm motility of at least 20% to 30%, the prognosis appears to be good with partner insemination. Theoretically, increasing the number of motile sperm reaching the egg should improve fertility whenever decreased numbers and motility of normally functioning sperm is the primary problem. Unfortunately, the pregnancy rates after partner IUI for the treatment of severe male factor infertility have been disappointing.12 This is probably because markedly abnormal parameters on routine semen analysis often reflect a sperm defect that decreases the ability to fertilize eggs. This type of defect is unlikely to be overcome by increasing the number of sperm to which the egg is exposed at the site of fertilization. In patients with severely abnormal parameters on semen analysis and those with male factor infertility not amenable to partner insemination, more effective treatment will be either donor insemination or in vitro fertilization (IVF) with intracytoplasmic sperm injection (ICSI). Female Factor Infertility
Female reproductive conditions can also make it difficult to place semen high in the vagina during coitus. Such conditions that can benefit from partner insemination include severe vaginismus and other psychological problems, and less common anatomic conditions. Little data exists documenting the success of partner insemination for these conditions. Women with cervical factor infertility will benefit from IUI, because this approach bypasses the cervical abnormalities that decrease fertility. This includes women with abnormal cervical mucus secondary to noninfectious chronic cervicitis and women with scant mucus or cervical stenosis, usually the result of cervical surgery. However, even women with a normal cervix and mucus appear to benefit from IUI, because the cervix appears to be the limiting factor in sperm reaching the site of fertilization in the tube.
Unexplained (i.e., idiopathic) infertility is diagnosed after all known etiologies of infertility have been excluded. In these cases, semen analyses are normal and there is no evidence of any female causes of infertility, such as ovulation defects, tubal factor, endometriosis, and cervical factor. The average incidence of unexplained infertility is approximately 15% among infertile couples. In couples with unexplained infertility, partner IUI has been demonstrated to improve pregnancy rates when used in conjunction with superovulation.13 In a meta-analysis of almost 1000 superovulation cycles for unexplained infertility, partner IUI was found to almost double pregnancy rates (20%) compared to timed intercourse alone (11%). Partner IUI appears to overcome one or more unknown fertility deficiencies that we cannot currently detect. Theoretically, this might be decreased sperm transport from the vagina to the tube secondary to either a sperm defect or an abnormality in sperm transport mechanisms in the female reproductive tract. In other cases, a subtle sperm fertilization defect might exist that is surmounted by increasing the absolute number of sperm reaching the egg.
Donor Insemination In the past, the only available options for couples with severe male factor infertility (e.g., severe oligospermia, or failure to conceive using partner insemination) desiring children were either donor insemination or adoption. Since the widespread availability of IVF using ICSI, many couples with severe male factor infertility have chosen to procreate their own genetic children using these techniques. However, donor insemination remains an option when IVF/ICSI has been unsuccessful. Alternatively, many candidates for IVF/ICSI initially choose donor insemination because it is less invasive and ultimately more likely to achieve pregnancy for couples with limited resources. Some women choose donor insemination because they are not candidates for IVF/ICSI. Perhaps the most obvious situation is women without male partners who seek pregnancy. The use of donor insemination is also indicated when the male partner
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Section 6 Infertility and Recurrent Pregnancy Loss has no viable sperm (i.e., azoospermia) or when IVF/ICSI fails to achieve fertilization. Finally, men with a known genetic disorder often choose donor insemination to avoid transmission to their children.
timing strategies are based on either detection of a urinary LH surge or administration of an ultrasound-timed dose of human chorionic gonadotropin (hCG ) to trigger ovulation. LH Surge
Couples choose a donor from profiles of nonidentifiable information. This information usually includes racial or ethnic background, blood type, physical characteristics, and certain social characteristics. Many women who become pregnant as a result of donor insemination desire to use the same donor for further pregnancies.
A commonly used method for timing of IUI is based on urinary LH measurement. Ovulation occurs 40 to 45 hours after the onset of the LH surge.21 Insemination is thus planned for the day after detection of a rise in urinary LH. This approach offers the simplest and most cost-effective of the indirect methods for predicting ovulation and is just as effective in achieving pregnancy as more complex ones.22,23
Donor Evaluation
Ultrasound and Human Chorionic Gonadotropin
Thorough evaluation of all potential sperm donors (other than sexually intimate partners) is necessary to avoid inadvertent transmission of sexually transmitted diseases or known genetic syndromes.16 All donors undergo a review of relevant medical records, personal and family history, and a physical examination. Determination of normal semen characteristics is extremely important. In addition, blood grouping and karyotyping is performed. Each donor must be screened for risk factors and clinical evidence of communicable diseases, including:
Transvaginal ultrasonography is widely used to monitor the size of the follicles and to assess the timing of ovulation. Follicles become recognizable once they grow to 2 to 3 mm in diameter. After 8 mm, linear follicular growth occurs at a rate of approximately 2 to 3 mm per day. Ovulation occurs during a natural cycle when the lead follicle reaches 15 to 24 mm in size. Injection of hCG can be given to induce predictable ovulation when at least one follicle diameter is between 17 and 21 mm. For optimal pregnancy rates, IUI is scheduled 24 to 36 hours after the injection.
Donor Selection
● ● ● ● ●
● ● ●
human immunodeficiency virus types 1 and 2 human T-lymphotropic virus types I and II hepatitis B and C cytomegalovirus human transmissible spongiform encephalopathy (including Creutzfeldt-Jakob disease) Treponema pallidum Chlamydia trachomatis Neisseria gonorrheae
If the donor is deemed acceptable and is aware of the ethical and legal implications, semen can be collected. All donor semen samples are cryopreserved and quarantined for 6 months. Before a donor sample is used for insemination, the donor is retested and determined if eligible. Success Rate
The actual per cycle fecundity rate with donor IUI is dependent on multiple factors. A meta-analysis of seven studies demonstrated that IUI yielded a higher pregnancy rate per cycle than intracervical insemination with donor frozen sperm.17 Overall, the average live birth rate per cycle of donor IUI is approximately 10%.18
IUI TIMING, COST, AND FREQUENCY Timing
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Timing of insemination in relationship to ovulation is one of the crucial factors in the success of IUI. Although viable sperm remain in the female reproductive tract for up to 120 hours after coitus, the best pregnancy rates are obtained when IUI is performed as close as possible to ovulation.19,20 In the past, IUI was performed on the estimated day of ovulation based on basal body temperature rises during previous cycles. However, to optimize fecundity, modern prospective
IUI Cost The cost-effectiveness of the treatment is an important consideration when deciding on the most appropriate infertility treatment option.24 The cost of insemination varies from clinic to clinic, but is presently less than $500 per IUI, including sperm preparation and injection of the prepared sample. This compares favorably with the cost of other appropriate ART approaches. Even when the cost of ovulation induction medication and monitoring are included, the cost per live birth for IUI after superovulation has been calculated to be less than half the cost of IVF treatment.25
IUI Frequency It is recommended that IUI be performed either one or two times during each cycle. Performing two inseminations per cycle is likely to be especially advantageous when timing in relationship to ovulation is less precise. Although it seems intuitive that fecundity should be increased by two inseminations per cycle, it remains inconclusive whether the increased fecundity is worth doubling the patients’ cost and inconvenience compared to one insemination per cycle.26–30 A recent meta-analysis of more than 1000 IUI cycles revealed a slightly higher but statistically insignificant difference between the per cycle fecundity rate for two inseminations (14.9%) compared to one insemination per cycle (11.4%).31 Accordingly, one well-timed insemination appears to offer the best balance between efficacy and cost.
SPERM PREPARATION FOR IUI Sperm preparation methods are used to process semen samples such that viable sperm are separated from seminal plasma. This is necessary before IUI to avoid the consequences of intrauterine injecting of semen plasma proteins and prostaglandins.32 Although seminal plasma protects the spermatozoa from stressful
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Chapter 36 Artificial Insemination Table 36-3 Common Techniques Used for Sperm Preparation Prior to Intrauterine Insemination Washing Swim-up techniques Swim-up from pellet Swim-up from ejaculate Swim-up from ejaculate into hyaluronic acid Density gradient centrifugation Glass wool filtration Mechanical aids
conditions such as oxidative stress,33 it also contains factors that inhibit the fertilizing ability of the spermatozoa and reduce the induction of capacitation.34,35 Sperm preparation involves removing the seminal plasma efficiently and quickly and eliminating dead sperm, leukocytes, immature germ cells, epithelial cells, and microbial contamination. Several methods for sperm preparation are currently used (Table 36-3). The ideal sperm preparation method recovers highly functional spermatozoa and enhances sperm quality and function without inducing damage. It is also cost-effective and allows for the processing of a large volume of the ejaculate, which in turn maximizes the number of spermatozoa that are available.36 The ideal sperm preparation method minimizes the risk of reactive oxygen species generation, which can adversely affect DNA integrity and sperm function in vitro.33,37 Several preparation methods incorporate methylxanthines and pentoxifyllines to increase sperm motility and improve the fertilization outcome. The first step in sperm preparation is the performance of a semen analysis according to the World Health Organization (WHO) standards to determine the prewash quality of the sample. Throughout the semen analysis and preparation, it is important to use sterile technique and media both to minimize the risk of iatrogenic intrauterine infection and because sperm can be damaged by bacterial contamination.
Swim-up Techniques Swim-up techniques are based on active self-migration of motile spermatozoa into the washing medium. Allowing sperm to swim up from ejaculate avoids the need for centrifugation, which can lead to oxidative damage of the sperm. However, this technique can be used only for ejaculate with a high degree of progressive motile spermatozoa, because the percentage of motile sperm recovered depends on sperm motility. For the swim-up technique, a layer of wash media is gently layered over the semen sample. The sample is incubated so that the motile sperm can swim out of the semen sample into the media. The media is then carefully removed from the semen fluid and used for IUI. If the initial semen sample has normal sperm parameters, recovery of reasonable number of sperm with at least 90% motility is common. The entire procedure takes 2 hours.
Basic Sperm Washing Sperm washing, the oldest and perhaps the simplest technique, removes the seminal fluid with little enrichment of motile sperm. The semen sample is diluted in a sperm wash media containing
antibiotics and protein supplements in a conical centrifuge tube. The specimen is centrifuged such that all cells congregate in a pellet, and the supernatant wash solution is carefully removed. The pellet is resuspended in wash media, and the centrifugation is repeated. The final pellet, from which all seminal fluid has been eliminated, is resuspended in a small volume of wash media for IUI. The entire procedure takes less than an hour.
Density Gradient Centrifugation The density gradient method is a sperm washing method that both removes semen fluid and separates living sperm from other material, including dead sperm cells, white blood cells, and bacteria. For this method, a density gradient is prepared by layering suspensions of different concentrations of coated colloidal silica particles (e.g., Percoll) in a conical centrifuge tube, with the higher concentrations more superior. The liquefied semen sample is placed over the upper layer and the tube is centrifuged. The supernatant is removed from the pellet, and the process is repeated. The final pellet is resuspended in wash media and used for IUI. Density gradient sperm washes take approximately 1 hour.
Glass Wool Filtration The glass wool filtration method is another method for removing seminal fluid and separating living sperm from other cellular material after sperm has been washed. For this technique, the semen samples are first diluted with wash media and centrifuged in a manner similar to sperm washing. The resulting pellet is resuspended in wash media and placed on glass wool columns, created by inserting glass wool into the barrel of a 3-mL syringe. The washed sperm solution is allowed to filter through the column by gravity, and the filtrate is collected for IUI.
Which Preparation Method is the Best? Presently, there is no general consensus as to the best sperm preparation technique for IUI. In general, swim-up, simple sperm washing, density gradient centrifugation, and glass wool filtration methods all effectively produce adequate sperm samples. However, some preparation techniques appear better suited for particular types of samples; thus, the technique chosen should be tailored to individual samples. The preparation techniques most commonly used today are the double density gradient centrifugation and the glass wool filtration sperm washing techniques. These techniques have been shown to improve the number of morphologic normal spermatozoa with grade A motility and with normal chromatin condensation in the prepared sample.38–40 In addition, these techniques best reduce the amount of reactive oxygen species and leukocytes in the prepared sample and provide spermatozoa with minimal chromatin and nuclear DNA anomalies and high nuclear maturity rates. For semen samples with normal or near-normal sperm parameters, one study has shown that swim-up and density gradient techniques result in higher pregnancy rates compared to the washing, swim-down, and refrigeration/heparin techniques.41 For poor samples, the density gradient centrifugation and glass wool filtration techniques appear to be superior. In cases of very low sperm counts, simple sperm washing will recover the highest number of sperm, both motile and nonmotile.
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Section 6 Infertility and Recurrent Pregnancy Loss curved tip is directed in a new course and re-advanced. This procedure is continued until the catheter can be advanced without resistance approximately 5 to 6 cm into the uterine cavity. Rarely, a cervical tenaculum is required to apply downward traction on the cervix to “straighten” an exceptionally tortuous canal. A second method for navigation of the endocervical canal for IUI is by using a semirigid yet flexible catheter that has no memory.42 Pressure is used to force the catheter to follow the course of the canal. This technique often requires the use of a cervical tenaculum to apply countertraction. Because the diameter of some of these types of catheters is usually larger in caliber (greater than 3 mm), dilatation is sometimes required in the presence of cervical stenosis.
A
FACTORS THAT PREDICT PREGNANCY RATES The highest pregnancy rates with IUI are seen within three to four cycles.43 The average live birth rate per cycle is approximately 10%.18 Cumulative pregnancy rates depend on the characteristics of the couples being treated. In most reports, the cumulative pregnancy rate reaches plateau after three to six cycles. It is difficult to predict with certainty whether pregnancy will occur. Several models have been proposed but have not been validated.44,45
B Figure 36-1 Intrauterine insemination catheters: A, Tefcat catheter attached to a syringe (Cook Group, Bloomington, Ind.); B, CryoBioSystem catheter (CryoBioSystem, Paris).
IUI TECHNIQUE
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IUI is performed using one of several commercially available intrauterine insemination catheters connected to a 2-mL syringe (Fig. 36-1). With the fully awake patient in a dorsal lithotomy position, the cervix is visualized with a bivalve vaginal speculum. After excess vaginal secretions are wiped from the external cervical os, the tip of a thin flexible catheter is passed into the uterine cavity, and the sperm sample, suspended in less than 1 mL of wash media, is gently expelled high in the uterine cavity. Increased resistance during injection suggests that the catheter is kinked or the tip might be inadvertently lodged in the endometrium or tubal ostia. In this situation, the catheter should be withdrawn 1 cm, and injection reattempted. After IUI, the catheter is slowly removed and the patient allowed to remain supine for 10 minutes after insemination in case she experiences a vasovagal reaction. Occasionally, there is difficulty navigating the often tortuous course of the endocervical canal with the tip of the insemination catheter. There are two common approaches to this blind procedure. Most commonly, a thin catheter (external diameter less than 2 mm) with a “memory” is used so that the tip can be bent 20 to 90 degrees, thus allowing angular navigation in any direction by carefully twisting the catheter as it is gently advanced. Resistance in any direction requires that the catheter tip be withdrawn a matter of millimeters, twisted such that the
Male Factors That Predict IUI Success Men who have normal seminal characteristics have a higher chance of initiating a successful pregnancy as a result of IUI than those with abnormal results on semen analysis. This association is probably related to two associated factors. First, an abnormal semen analysis is often associated with an impaired fertilization capacity. Secondly, pregnancy rates positively correlate with the total number of motile sperm recovered for IUI, and this number is often lower in men with abnormal results on semen analysis. Semen Analysis Characteristics
Semen characteristics clearly affect IUI outcome.46 IUI is a successful treatment for mild male factor infertility, defined as a total motile sperm count of more than 5 million and Kruger morphology of more than 5%.47 In a study in patients with mild male factor infertility, a live birth rate of 19% per cycle was reported.47 When prepreparation semen analyses characteristics are evaluated, the chances of pregnancy after IUI correlate best with morphology. A meta-analysis of six studies using strict morphology criteria (Kruger) showed that when the prewashed semen specimen had more than 4% normal sperm morphology, the chances of pregnancy after IUI were significantly increased.48 If the WHO standards were used to evaluate sperm morphology, the presence of more than 30% abnormal sperm in the ejaculate adversely influenced the pregnancy rate.49 Total Motile Sperm Count
The sperm variable most clearly associated with pregnancy rates after IUI is the total motile sperm count after sperm wash or swim-up. In a retrospective study of 9963 IUI cycles, the likelihood of subsequent pregnancy was maximized when the IUI sample contained more than 4 million motile sperm numbers
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Chapter 36 Artificial Insemination and sperm motility was greater than 60%.50 Total motile sperm count was reported to affect IUI outcome in 1115 cycles in 332 infertile couples.51 No pregnancy occurred in cases where the total motile sperm count before semen preparation was less than 1 × 106. Sperm DNA Damage Tests
Efforts have been made to find objective assessments of sperm quality that will predict pregnancy outcomes in men with abnormal results on semen analysis. Three experimental assessments are the sperm chromatin structure assay, DNA fragmentation index, and terminal deoxynuceotidyl transferase-mediated deoxyuridine triphosphate-nick end labeling (TUNEL). The sperm chromatin structure assay provides an objective assessment of sperm chromatin integrity and can be useful as a fertility marker.52 In a recent study, DNA damage as measured using this test was found to predict the outcome of IUI. The DNA fragmentation index (DFI) has been shown to be negatively correlated with the overall pregnancy rate in women undergoing IUI, IVF, or ICSI.53 The chances of achieving pregnancy are significantly lower when the sperm DFI is greater than 27% after IUI processing.54 TUNEL evaluates the degree of sperm DNA fragmentation and stability.55 In one study, lower degrees of DNA fragmentation after IUI sperm preparation correlated with higher pregnancy rates, and no pregnancy occurred when more than 12% of sperm in an IUI specimen were TUNELpositive. Hypo-osmotic Swelling Test
The hypo-osmotic swelling test evaluates the membrane integrity of the sperm tail, detects the differences on the sperm surface, and detects subtle damage in membrane properties, which reduces the ability of spermatozoa to induce a viable embryo.56 A sample “passes” the hypo-osmotic swelling test when at least 50% of sperm in an IUI sample swell.57 Sperm specimens that fail the hypo-osmotic swelling test appear to have decreased fertilizing ability, and thus pregnancy rates after IUI are lower. The miscarriage rate was also higher when result of hypo-osmotic swelling test was less than 50%. Antisperm Antibodies
Both IUI and IVF appear to be effective in treating subfertility in men with antisperm antibodies, although IVF/ICSI appears to have higher pregnancy rates per cycle than IUI.58 However, to date no large prospective, randomized, controlled trial has compared IUI to IVF/ICSI in men with antisperm antibodies. In severe cases of antisperm antibodies, especially when the sperm head is involved, IVF/ICSI will often be required to achieve pregnancy.59,60
Female Factors That Predict IUI Success Many studies have examined the different variables affecting pregnancy rates after IUI.25,61–64 The influence of lifestyle habits (e.g., smoking, caffeine consumption, and weight) is unclear but is most probably significant. There appear to be several important female factors that are useful in predicting pregnancy rates after IUI. These factors are maternal age, duration of infertility, and fenale infertility factors.65
Maternal Age
A woman’s age is an indirect indicator for oocyte quality, and it has a significant effect on the pregnancy rates. An age-related decline in female fecundity has been documented in women undergoing IUI.43,64 Successful pregnancy rates decrease after age 35 and reduce dramatically after age 40. However, pregnancies can occur at relatively advanced maternal ages, and satisfactory pregnancy rates can be obtained with IUI among women age 40 to 42.66,67 Duration of Infertility
The longer the duration of infertility, the lower the pregnancy rates are after IUI.25,43,65 Although the precise limits of infertility duration for recommending IUI have not been clearly established, the pregnancy rate may be seriously compromised when infertility has lasted 3 or more years. Female Fertility Factors
The success of artificial insemination depends not only on the quality of oocytes and spermatozoa, but also on the receptivity of the endometrium. In a retrospective study, the presence of uterine anomalies negatively affected the success of IUI.65 Endometrial thickness and pattern is also predictive of IUI success. In a study on women undergoing controlled ovarian hyperstimulation and IUI, a trilaminar endometrium on the day of IUI provided a favorable prediction of pregnancy. However, endometrial thickness and Doppler surveys of the spiral and uterine arteries and dominant follicle gave no useful predictive value.68 A study evaluated the role of endometrial volume measurement in predicting the pregnancy rate in women receiving controlled ovarian hyperstimulation and IUI.69 An endometrial volume of less than 2 mL on three-dimensional ultrasound on the day of insemination was associated with a poor likelihood of pregnancy. Pregnancy rates after IUI are dependent on ovum pickup and transport. It follows that pregnancy rates after IUI are decreased by other causes of female infertility, including tubal factor and endometriosis.
RISKS AND COMPLICATIONS Complications associated with IUI are extremely uncommon. Most of the complications that occur are related to the medications used to recruit multiple follicles before IUI.
Pelvic Infections Limited cramping during or after an IUI procedure from the catheter or cervical tenaculum is common. These symptoms are self-limiting and should resolve within hours of the procedure. Continued discomfort can be an indication of a developing pelvic infection, which has been estimated to occur in less than 2 per 1000 IUI procedures.63 Early diagnosis and treatment are essential in these rare cases to minimize the risk to the patient, particularly that of subsequent decreased fertility.
Vasovagal Reaction Vasovagal reactions can occur as a result of manipulation of the cervix. The resulting vasodilation and decreased heart rate can lead to hypotension, most commonly manifest by diaphoresis in
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Section 6 Infertility and Recurrent Pregnancy Loss a supine patient. Sitting or standing increases the risk of syncope, which is unlikely to occur supine. Persistent symptomatic vasovagal reactions in a supine patient will often respond to the patient crossing her legs.70 More severe cases might require treatment with intramuscular atropine injection (0.5 mg).
Allergic Reaction Allergic reactions, including anaphylaxis, can occur after IUI in response to potential allergens in the wash media. Reactions have been reported to both the bovine serum albumin and antibiotics (penicillin and streptomycin) commonly used in the wash media.71,72 Of these, penicillin allergies are the most common in the general population. Allergic reactions after IUI can range from a mild skin rash to life-threatening anaphylaxis with laryngeal edema, bronchospasm, and hypotension. For the rare patient experiencing an allergic reaction after IUI, the use of wash media free of albumin and antibiotics is advised.
Antisperm Antibodies When IUI was first introduced, there was a concern that the procedure could result in the development of serum antisperm antibodies. Fortunately, after 40 years of experience, it appears that exposure of the upper reproductive tract to washed spermatozoa during IUI does not stimulate the appearance of clinically significant female antisperm antibodies.73
Pregnancy-Related Complications Multiple Pregnancies
The risk of multiple pregnancies is not increased by IUI. However, medications used to recruit multiple follicles before IUI do increase this risk. Clomiphene citrate is associated with a twin risk of 5% to 10% and rare higher-order multiples. Injectable gonadotropins are associated with multiple pregnancy rates of 14% to 39%.74–76 Careful monitoring of the number of periovulatory follicles and peak estradiol levels might decrease the rate of multiple pregnancies.61,74,77 In general, women are at high risk if they are younger than age 30, have more than six preovulatory follicles, and a peak serum estradiol level greater than 1000 pg/mL. Spontaneous Abortion and Ectopic Pregnancy
The risk of spontaneous abortion appears to be increased after IUI compared to the fertile population and is in the range of 20% to 25%.1,78 The increased risk is probably not directly attributed to IUI but is most likely due to the underlying infertility problem. Likewise, ectopic pregnancy rates depend largely on the presence of predisposing factors such as tubal disease and do not appear to be attributed to the IUI procedure.79
PSYCHOLOGICAL, ETHICAL, AND LEGAL ISSUES OF DONOR INSEMINATION Parents Donor insemination has more psychological implications than partner insemination. Before donor insemination, several issues should be discussed in detail, including the couple’s desire or
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need to start a family, the alternatives that the male partner has to procreate his own genetic children, and financial factors. It is recommended that the couple undergo counseling before the procedure so that they can both face their feelings concerning infertility, donor insemination, and other concerns. The male partner may experience a loss of self-esteem and fear losing his partner because of infertility. Both partners may feel guilty or angry toward each other for having an infertility problem. Infertility tends to separate the couple, especially when one side is uncooperative. Support groups or professional counseling can be helpful.
Offspring There are expert opinions both for and against disclosing to the child that he or she is the product of donor insemination. Before undergoing donor IUI, the couple should decide if they plan to disclose the nature of the procedure and the biologic implications to their friends, relatives and, ultimately, their child. If knowledge of the procedure is shared with friends and relatives, there is always the risk that the truth will be disclosed to the child by someone other than the parents. These sometimesunderappreciated issues can cause unnecessary grief if not adequately addressed prior to therapy.
Legal Issues It is imperative that both partners understand the legal issues concerning donor insemination. Before donor insemination, both partners should sign an informed consent that clearly states the rights and obligations of the parties involved and those of the child. Although laws vary from state to state, when sperm is obtained from a sperm bank, the donor universally has no legal access to the couple’s identity. In cases where couples elect to use a donor known to them, an attorney should be obtained to draft the appropriate papers to terminate any parental rights of the donor and give the couple full custody of any subsequent child. In some states, the child conceived from donor sperm may have the right to obtain identifying information about the donor once they reach adulthood.
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Artificial insemination is a useful and cost-effective treatment option in selected groups of infertile couples. Infertility due to cervical factor and mild male factor (without any associated female factor) can be treated with intrauterine insemination without ovarian stimulation. Artificial insemination appears to be more cost-effective and simple compared to the IVF/ICSI if the couples are selected appropriately. In spite of extensive research, we are still not able to predict the success of artificial insemination in a specific couple. Duration of the infertility negatively impacts the artificial insemination success. Couples with unexplained infertility have better success with artificial insemination than natural intercourse. Couples with unexplained infertility should use controlled ovarian hyperstimulation along with the artificial insemination.
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Section 6 Infertility and Recurrent Pregnancy Loss 45. Bedaiwy MA, Sharma RK, Alhussaini TK, et al: The use of novel semen quality scores to predict pregnancy in couples with male-factor infertility undergoing intrauterine insemination. J Androl 24:353–360, 2003. 46. Hendin BN, Falcone T, Hallak J, et al: The effect of patient and semen characteristics on live birth rates following intrauterine insemination: A retrospective study. J Assist Reprod Genet 17:245–252, 2000. 47. Zayed F, Lenton EA, Cooke ID: Comparison between stimulated in vitro fertilization and stimulated intrauterine insemination for the treatment of unexplained and mild male factor infertility. Hum Reprod 12:2408–2413, 1997. 48. Van Waart J, Kruger TF, Lombard CJ, Ombelet W: Predictive value of normal sperm morphology in intrauterine insemination (IUI): A structured literature review. Hum Reprod Update 7:495–500, 2001. 49. van Noord-Zaadstra BM, Looman CW, Alsbach H, et al: Delaying childbearing: Effect of age on fecundity and outcome of pregnancy. BMJ 302:1361–1365, 1991. 50. Stone BA, Vargyas JM, Ringler GE, et al: Determinants of the outcome of intrauterine insemination: Analysis of outcomes of 9963 consecutive cycles. Am J Obstet Gynecol 180:1522–1534, 1999. 51. Campana A, Sakkas D, Stalberg A, et al: Intrauterine insemination: Evaluation of the results according to the woman’s age, sperm quality, total sperm count per insemination and life table analysis. Hum Reprod 11:732–736, 1996. 52. Richthoff J, Spano M, Giwercman YL, et al: The impact of testicular and accessory sex gland function on sperm chromatin integrity as assessed by the sperm chromatin structure assay (SCSA). Hum Reprod 17:3162–3169, 2002. 53. Saleh RA, Agarwal A, Nada EA, et al: Negative effects of increased sperm DNA damage in relation to seminal oxidative stress in men with idiopathic and male factor infertility. Fertil Steril 79(Suppl 3): 1597–1605, 2003. 54. Bungum M, Humaidan P, Spano M, et al: The predictive value of sperm chromatin structure assay (SCSA) parameters for the outcome of intrauterine insemination, IVF and ICSI. Hum Reprod 19:1401–1408, 2004. 55. Duran EH, Morshedi M, Taylor S, Oehninger S: Sperm DNA quality predicts intrauterine insemination outcome: A prospective cohort study. Hum Reprod 17:3122–3128, 2002. 56. Tartagni M, Schonauer MM, Cicinelli E, et al: Usefulness of the hypoosmotic swelling test in predicting pregnancy rate and outcome in couples undergoing intrauterine insemination. J Androl 23:498–502, 2002. 57. Ombelet W, Deblaere K, Bosmans E, et al: Semen quality and intrauterine insemination. Reprod Biomed Online 7:485–492, 2003. 58. Ohl DA, Naz RK: Infertility due to antisperm antibodies. Urology 46:591–602, 1995. 59. McLachlan RI: Basis, diagnosis and treatment of immunological infertility in men. J Reprod Immunol 57:35–45, 2002. 60. Lombardo F, Gandini L, Dondero F, Lenzi A: Antisperm immunity in natural and assisted reproduction. Hum Reprod Update 7:450–456, 2001. 61. Dickey RP, Olar TT, Taylor SN, et al: Relationship of follicle number, serum estradiol, and other factors to birth rate and multiparity in human menopausal gonadotropin-induced intrauterine insemination cycles. Fertil Steril 56:89–92, 1991.
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62. Dickey RP, Olar TT, Taylor SN, et al: Relationship of follicle number and other factors to fecundability and multiple pregnancy in clomiphene citrate-induced intrauterine insemination cycles. Fertil Steril 57:613–619, 1992. 63. Mathieu C, Ecochard R, Bied V, et al: Cumulative conception rate following intrauterine artificial insemination with husband’s spermatozoa: Influence of husband’s age. Hum Reprod 10:1090–1097, 1995. 64. Tomlinson MJ, Amissah-Arthur JB, Thompson KA, et al: Prognostic indicators for intrauterine insemination (IUI): Statistical model for IUI success. Hum Reprod 11:1892–1896, 1996. 65. Steures P, van der Steeg JW, Mol BW, et al: Prediction of an ongoing pregnancy after intrauterine insemination. Fertil Steril 82:45–51, 2004. 66. Haebe J, Martin J, Tekepety F, et al: Success of intrauterine insemination in women aged 40–42 years. Fertil Steril 78:29–33, 2002. 67. Khalil MR, Rasmussen PE, Erb K, et al: Homologous intrauterine insemination. An evaluation of prognostic factors based on a review of 2473 cycles. Acta Obstet Gynecol Scand 80:74–81, 2001. 68. Tsai HD, Chang CC, Hsieh YY, et al: Artificial insemination. Role of endometrial thickness and pattern, of vascular impedance of the spiral and uterine arteries, and of the dominant follicle. J Reprod Med 45:195–200, 2000. 69. Zollner U, Zollner KP, Blissing S, et al: Impact of three-dimensionally measured endometrial volume on the pregnancy rate after intrauterine insemination. Zentralbl Gynakol 125:136–141, 2003. 70. Krediet CT, van Dijk N, Linzer M, et al: Management of vasovagal syncope: Controlling or aborting faints by leg crossing and muscle tensing. Circulation 106:1684–1689, 2002. 71. Smith YR, Hurd WW, Menge AC, et al: Allergic reactions to penicillin during in vitro fertilization and intrauterine insemination. Fertil Steril 58:847–849, 1992. 72. Sonenthal KR, McKnight T, Shaughnessy MA, et al: Anaphylaxis during intrauterine insemination secondary to bovine serum albumin. Fertil Steril 56:1188–1191, 1991. 73. Moretti-Rojas I, Rojas FJ, Leisure M, et al: Intrauterine inseminations with washed human spermatozoa does not induce formation of antisperm antibodies. Fertil Steril 53:180–182, 1990. 74. Valbuena D, Simon C, Romero JL, et al: Factors responsible for multiple pregnancies after ovarian stimulation and intrauterine insemination with gonadotropins. J Assist Reprod Genet 13:663–668, 1996. 75. Goldfarb JM, Peskin B, Austin C, Lisbona H: Evaluation of predictive factors for multiple pregnancies during gonadotropin/IUI treatment. J Assist Reprod Genet 14:88–91, 1997. 76. Tur R, Buxaderas C, Martinez F, et al: Comparison of the role of cervical and intrauterine insemination techniques on the incidence of multiple pregnancy after artificial insemination with donor sperm. J Assist Reprod Genet 14:250–253, 1997. 77. Pasqualotto EB, Falcone T, Goldberg JM, et al: Risk factors for multiple gestation in women undergoing intrauterine insemination with ovarian stimulation. Fertil Steril 72:613–618, 1999. 78. Lalich RA, Marut EL, Prins GS, Scommegna A: Life table analysis of intrauterine insemination pregnancy rates. Am J Obstet Gynecol 158:980–984, 1988. 79. Aboulghar MA, Mansour RT, Serour GI: Ovarian superstimulation in the treatment of infertility due to peritubal and periovarian adhesions. Fertil Steril 51:834–837, 1989.
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37
Induction of Ovulation Mohamed F. Mitwally and Robert F. Casper
INTRODUCTION Induction of ovulation, or stimulation of ovarian follicular development, is applied in several different clinical situations. These include restoration of ovulation in anovulatory women, ovarian superovulation (stimulating more than one mature follicle) in ovulatory women, and controlled ovarian hyperstimulation (stimulating the development of several mature follicles) for assisted reproduction. This chapter reviews the underlying scientific basis and clinical guidelines regarding the use of different oral medications for induction of ovulation. It focuses on a discussion of oral agents, including clomiphene citrate, insulin sensitizers, and aromatase inhibitors. Other drugs for ovarian stimulation used for assisted reproductive technology (ART), including preantral medications (injectable gonadotropins and gonadotropin-releasing hormone [GnRH] analogues), and specific agents applied for particular medical disorders, such as prolactin-lowering agents in cases of hyperprolactinemic anovulation, are discussed in Chapters 22 and 38.
PHYSIOLOGIC BASIS OF FOLLICULAR DEVELOPMENT AND OVULATION An understanding of normal physiology is an important basis for understanding ovulation induction. Ovulation is comprehensively discussed in Chapter 3. A brief description relevant to induction of ovulation is presented here.
Folliculogenesis Ovarian folliculogenesis is regulated by both endocrine and intraovarian mechanisms that coordinate the processes of cell proliferation and differentiation. The main follicular component of the ovarian cortex is the primordial follicle, consisting of an oocyte arrested at the diplotene stage of the first meiotic division, surrounded by a few flattened cells that will develop into granulosa cells.1 In response to an unknown signal, primordial follicles are gradually and continuously recruited to grow. Initial Follicular Growth
Initial follicular growth appears to be independent of pituitary gonadotropins. Follicle-stimulating hormone (FSH) does not appear to be essential for early follicle growth because in the absence of FSH follicles can still develop to the early antral stage. However, the involvement of FSH in the development of small follicles is supported by the presence of FSH receptors in
granulosa cells.1 Also, FSH activates granulosa cell proliferation and differentiation and reduces the number of atretic follicles grown in vitro.2 Such mitogenic action is facilitated by locally produced growth factors; the production or action of these factors may be modified by FSH.3 Extrapolating from hypogonadal mice in which oocytes grow to normal size and can acquire developmental competence, gonadotropins may not be necessary for oocyte development per se. However, gonadotropins are believed to play a general role in supporting overall oocyte maturation by supporting follicular development and preventing degeneration.4 Early Follicular Development
During the early stage of follicular development, the oocyte grows and the granulosa cells proliferate to form a preantral follicle. At the preantral stage, theca cells begin to differentiate from the surrounding stroma, and once the follicle reaches a speciesspecific size, it forms a fluid-filled space called an antrum within the granulosa cell layers.5 Antral follicles become acutely dependent on gonadotropins for further growth and development. Follicular growth (from primordial to preantral follicle stage) is continuous. However, less than 1% of primordial follicles present at the time of birth will ever proceed to ovulation, with the majority of follicles degenerating by atresia.6 During the later part of the luteal phase, when estrogen levels fall following the involution of the corpus luteum, gonadotropin levels increase, leading to continued development of a limited cohort of follicles. Subsequent development of this cohort during the follicular phase becomes dependent on continued stimulation by gonadotropins. FSH Threshold
FSH concentrations must exceed a certain level before follicular development will proceed.7 When this FSH threshold is surpassed in the normal cycle, the growth of a cohort of small antral follicles is stimulated and ensures ongoing preovulatory follicular development (Fig. 37-1).8 The duration of this period in which the threshold is exceeded (the FSH window) is limited in the normal cycle by a decrease in FSH, which occurs in the early to mid-follicular phase because of negative feedback from rising estrogen levels. Extending this window would allow the continuous development of more follicles. In the normal cycle, one follicle continues developing despite falling FSH levels because of an increased sensitivity to FSH8 while the remaining follicles respond to falling FSH levels by undergoing atresia, as shown in Figure 37-1.
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Section 6 Infertility and Recurrent Pregnancy Loss Human follicle development FSH threshold/window concept
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Figure 37-1 The intercycle rise in serum follicle-stimulating hormone (FSH) concentrations exceeds the threshold for recruitment of a cohort of follicles for further development. The number of follicles recruited is determined by the time (FSH window) for which the serum FSH is above the threshold at which recruitment occurs. Adapted from Fauser BC, van Heusden AM: Manipulation of human ovarian function: Physiological concepts and clinical consequences. Endocr Rev 18:71, 1997.
When the follicle reaches a certain level of development, sustained high circulating levels of estradiol produced by the preovulatory follicle will initiate the midcycle surge in luteinizing hormone (LH) that will trigger ovulation. The surge initiates a gene cascade in granulosa cells, the products of which initiate luteinization, signal the egg to commence meiotic maturation, and lead to rupture of the follicle wall.9
Corpus Luteum Development The preovulatory surge of gonadotropins induces ovulation and differentiation of residual follicular cells that form the corpus luteum and begin to produce progesterone and estrogen at high rates. Theca cells express the enzymes necessary to convert cholesterol to androgens but lack the enzymes necessary to convert androgens to estrogens. Conversely, granulosa cells produce progesterone but are unable to convert pregnenolone or progesterone to androgens. The preovulatory LH surge results in luteinization of granulosa and theca cells and alters the steroidogenic pathway so that progesterone is the primary steroid hormone produced after luteinization. However, the corpus luteum retains the ability to produce estrogen. Adequate luteal progesterone is secreted to allow maintenance of pregnancy until a conceptus-derived source of progesterone, the placenta, can produce adequate amounts of this steroid to support pregnancy.10
OVULATION INDUCTION Indications
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pituitary and hypothalamus. In addition, adequate functioning of other endocrine glands such as the thyroid and adrenal glands is important in orchestrating the interaction between the hypothalamus, pituitary, and ovaries that results in ovulation. Any derangement of any of these systems may result in dysfunctional ovarian follicular development or even the complete failure of ovulation. The presence of subtle abnormalities despite the occurrence of ovulation is believed to be responsible, at least in part, for what is thought to be unexplained infertility in some women and perhaps for endometriosis-related infertility.
Normal follicular development culminates in ovulation of a mature oocyte, followed by the development of a corpus luteum producing adequate amounts of progesterone. This sequence of events is orchestrated by the interaction of local ovarian factors and endocrine factors from remote tissues, including the
Ovulatory Dysfunction Classification Clinically obvious anovulation or oligo-ovulation has been traditionally classified into three groups: World Health Organization (WHO) group I, II, and III anovulation.11 Women in WHO group I suffer from a defect at the level of the hypothalamus/pituitary. They are estrogen deficient with normal or low FSH or prolactin levels and have no space-occupying lesion in the hypothalamic/pituitary region. They typically have amenorrhea and do not bleed in response to progestin challenge. Women in WHO group II are not estrogen deficient. Their FSH and prolactin levels are normal. They typically experience oligomenorrhea, but they may have anovulatory cycles or amenorrhea with bleeding in response to a progestin challenge. Included in this group are women with polycystic ovary syndrome (PCOS). Women in WHO group III include those with elevated gonadotropins secondary to primary ovarian failure mainly due to diminished ovarian reserve and the loss of ovarian follicles. These women are resistant to various methods of ovarian stimulation, and the best approach for their anovulationassociated infertility is oocyte donation.
Medications for Ovarian Follicle Stimulation The available medications for stimulating ovarian follicular development include oral agents, mainly antiestrogens, better termed selective estrogen receptor modulators (SERM), and medications delivered by injections: gonadotropins and GnRH agonists. For more than four decades, an oral agent, clomiphene citrate, and injectable gonadotropins have almost been exclusively used for stimulating ovarian follicular development. Gemzell and his coworkers announced the first successful induction of ovulation using human pituitary gonadotropins in 1958 and the first pregnancy in 1960.12,13 One year later, Bettendorf and his group reported a similar experience.14 In 1961, Greenblatt and his coworkers published the first results of ovulation induction achieved by the use of clomiphene citrate (at that time known as MRL/41).15 In the past decade, insulin sensitizers have been introduced into clinical practice for ovulation induction for patients with PCOS and significant insulin resistance. Most recently, aromatase inhibitors have been used as an alternative to clomiphene citrate for ovulation induction or to improve the outcome of controlled ovarian stimulation with gonadotropins.
CLOMIPHENE CITRATE For more than 40 years, clomiphene citrate has been the most commonly used oral agent for induction of ovulation. Since the
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Chapter 37 Induction of Ovulation early 1960s, results of clomiphene citrate treatment have not changed appreciably, despite the advent of modern immunoassays for steroid hormones, advances in ultrasound technology for cycle monitoring, and the introduction of commercial ovulation predictor kits that allow accurate identification of the midcycle LH surge. It is interesting to note that clomiphene citrate is considered pregnancy risk category X. Studies in rats and mice have shown a dose-related increase in some types of malformations and an increase in mortality. This is particularly important when considering the relatively long half-life of about 5 days to 3 weeks (depending on the isomer) and that clomiphene citrate may be stored in body fat.16–18 Fortunately, studies in humans have not found an association between clomiphene citrate and congenital defects.
Structure and Pharmacokinetics Chemically, clomiphene citrate is a nonsteroidal triphenylethylene derivative and is chemically related to diethylstilbestrol and tamoxifen. Like the latter of these compounds, clomiphene can be considered to be a SERM that can exhibit both estrogen agonist and antagonist properties depending on the prevailing levels of endogenous estrogen. Estrogen agonist properties are manifest only when endogenous estrogen levels are extremely low. Otherwise, clomiphene citrate acts mainly as an antiestrogen.16 Clomiphene citrate is cleared through the liver and excreted in the stool. About 85% of an administered dose is eliminated after approximately 6 days, although traces may remain in the circulation for much longer.17 Clomiphene citrate is a racemic mixture of two distinct stereoisomers, enclomiphene and zuclomiphene, having different properties. Available evidence indicates that enclomiphene is the more potent antiestrogenic isomer and the one primarily responsible for the ovulationinducing actions of clomiphene citrate.16–18 Levels of enclomiphene rise rapidly after administration and fall to undetectable concentrations after few days. Zuclomiphene, the transisomer of clomiphene citrate, is cleared far more slowly; levels of this less active isomer remain detectable in the circulation for more than 1 month after treatment and may actually accumulate over consecutive cycles of treatment.18
Pharmacodynamics and Mode of Action Clomiphene binds to estrogen receptors throughout the body due to its structural similarity to estrogen. However, unlike natural estrogen, which only binds estrogen receptors for a period of hours, clomiphene citrate binds estrogen receptors for an extended period of time, weeks rather than hours. Such extended binding ultimately depletes estrogen receptor concentrations by interfering with the normal process of estrogen receptor replenishment.15 The antiestrogenic effect of action of clomiphene citrate on the hypothalamus, and possibly the pituitary, is believed to be its main mechanism for ovarian stimulation. Depletion of hypothalamic estrogen receptors prevents correct interpretation of circulating estrogen levels; estrogen concentrations are falsely perceived as low, leading to reduced estrogen-negative feedback on GnRH production by the hypothalamus and gonadotropin (FSH and LH) production by the pituitary. It is believed that the hypothalamus is the main site of action because in normally ovulatory women, clomiphene citrate treat-
ment was found to increases GnRH pulse frequency.19 However, actions at the pituitary level may also be involved because clomiphene citrate treatment increased pulse amplitude, but not frequency in anovulatory women with PCOS, in whom the GnRH pulse frequency is already abnormally high.20 During clomiphene citrate treatment, levels of both LH and FSH rise, then fall again after the typical 5-day course of therapy is completed. In successful treatment cycles, one or more dominant follicles emerge and mature, generating a rising tide of estrogen that ultimately triggers the midcycle LH surge and ovulation.19,20
Indications The two main indications for clomiphene citrate treatment in women are (1) induction of ovulation in women with anovulatory infertility, and (2) stimulation of multifollicular ovulation or enhancing ovulation in ovulatory infertile women (e.g., unexplained infertility). Clomiphene citrate is the initial treatment of choice for most anovulatory or oligo-ovulatory infertile women who are euthyroid and euprolactinemic while having adequate circulating levels of estrogen (WHO group II anovulation; e.g., PCOS). For anovulatory infertility, clomiphene citrate is effective only in conditions in which adequate levels of circulating estrogen exist to exert estrogen-negative feedback on gonadotropin production, and that could be antagonized by the antiestrogenic effect of clomiphene citrate. Women who do not respond to clomiphene citrate are those with very low circulating estrogen levels such as WHO groups I and III or women with defective hypothalamic-pituitary axis such as those with Sheehan’s syndrome and Kallmann syndrome. For “unexplained” infertility, clomiphene citrate enhances the chance of achieving pregnancy apparently by stimulating multifollicular development as well as alleviating possible subtle ovulation dysfunction. The downside is an increased risk of multiple pregnancy, primarily twins.
Clomiphene Citrate Administration Clomiphene citrate is administered orally for 5 days, starting on any day from the second to fifth day after the onset of spontaneous or progestin-induced menses. In anovulatory women, ovulation rates, conception rates, and pregnancy outcome are similar regardless of whether treatment is started on cycle day 2, 3, 4, or 5. Starting on day 5 has the theoretical advantage of giving more time to verify normal menses (and hopefully decreasing the chance of being pregnant) before starting therapy. Treatment typically begins with a single 50-mg tablet daily for 5 consecutive days, increasing by 50-mg increments in subsequent cycles until ovulation is induced. Once the effective dose of clomiphene citrate is established, there is no indication for further increments unless the ovulatory response is lost. Higher doses will not improve the probability of conception, but the risk of hyperstimulation and multiple pregnancy might increase. Although the dose required for achieving ovulation is correlated with body weight, there is no reliable way to predict accurately what dose will be required in an individual woman. Consequently, clomiphene citrate induction of ovulation amounts to an empirical incremental titration to establish the lowest effective dose for each individual.
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Figure 37-2 Cumulative pregnancy rates with clomiphene citrate and intrauterine insemination in patients with ovulatory and anovulatory infertility by Kaplan-Meier life table analysis. A, Filled circles, age <= 30; closed squares, age 31–35; open circles, age 36–40; open squares, age >= 41. B, Groups collapsed into two: closed circles, age <= 35; open squares, age >35. From Agarwal SK, Buyalos RP: Clomiphene citrate with intrauterine insemination: Is it effective therapy above the age of 35 years? Fertil Steril 65:759–763, 1996.
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The effective dose of clomiphene citrate for most women ranges from 50 to 250 mg/day, although some women will be found to be sensitive to clomiphene citrate and only require doses as low as 12.5 to 25 mg/day. Most women will ovulate at the lower doses, with 52% ovulating after 50 mg/day and another 22% after treatment with 100 mg/day. Although higher doses are sometimes required, the ovulation rates are usually low at these doses, with only 12% ovulating after 150 mg/day, 7% after 200 mg/day, and 5% after 250 mg/day. Most women who fail to respond to 150 mg/day of clomiphene citrate will ultimately require alternative or combination treatments.21,22 After the lowest ovulatory dose is determined, the same dose is repeated until pregnancy is achieved or a maximum number of approximately six cycles is reached. Pregnancy rates are highest during the first three cycles of clomiphene citrate treatment. The chances of achieving pregnancy are significantly lower beyond the third treatment cycle and uncommon beyond the sixth treatment cycle (Fig. 37-2). Therefore, it is rarely advisable to continue clomiphene citrate treatment beyond six treatment cycles.21 The recommendation regarding which dose to apply is clear in cases of anovulatory infertility (increments of 50 mg until ovulation is achieved, then the dose is maintained). However, this is not clear in cases with ovulatory infertility. There are no adequate studies regarding which dose or what response (number of mature follicles) would be optimal in these women. This uncertainty is related to the individual variability in response to clomiphene citrate treatment irrespective of the dose and to the absence of a clear correlation between pregnancy rates and the number of mature follicles or amount of clomiphene citrate administered. Moreover, the value of clomiphene citrate treatment in enhancing the chance of achieving pregnancy in cases with ovulatory infertility has been questioned22 and has not been proven by large controlled studies.
Treatment Monitoring Monitoring is required to ensure that ovulation is occurring during a clomiphene citrate treatment cycle. For most patients treated with clomiphene citrate, ovulation monitoring can often be done with any one of a number of low-cost, highly convenient methods conducted in the setting of a general obstetrician and gynecologist practice. Objective evidence of ovulation and normal luteal function are keys to successful treatment. The choice may vary and should be tailored to meet the needs of the individual patient.23 Basal Body Temperature
Basal body temperature (BBT) recordings provide a simple and inexpensive method for evaluating response to treatment. For this test, the woman takes and graphs her temperature every morning. A midcycle phase shift indicates that ovulation has occurred. Urinary LH Detection Kit
An ovulation prediction kit can identify the midcycle LH surge in urine and more precisely defines both the interval of peak fertility (day of surge detection and the next 2 days).24 Usually the LH surge is observed from 5 to 12 days after the last clomiphene citrate tablet.25 Ovulation will generally follow within 14 to 26 hours of detection of an LH surge. Consequently, timed coitus or intrauterine insemination (IUI) on the day after the first positive urinary LH test will have the highest pregnancy rates. Midluteal Progesterone
BBT charts and urinary LH detection kits can confirm that ovulation has occurred but do not document the quality of luteal
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Chapter 37 Induction of Ovulation function, which requires further tests—classically, a serum progesterone determination or endometrial biopsy. A progesterone level above 3 ng/mL is evidence of ovulation.26 Midluteal phase progesterone concentration (7 days after BBT shift or 7 to 9 days after urinary LH surge) offers more information. Levels exceeding 10 ng/mL are usually suggestive of an adequate luteal phase.27 Endometrial biopsy and “secretory” histology that results from the action of progesterone also provides evidence of ovulation. Endometrial “dating,” using established histologic criteria, has been traditionally suggested for diagnosing luteal phase adequacy.28 However, there is still much uncertainty about the importance of luteal phase defects diagnosed by serum progesterone levels or by endometrial biopsies, reflecting our poor state of knowledge regarding the actual mechanisms involved in endometrial receptivity and implantation.29,30 More sophisticated measures to monitor the outcome of clomiphene citrate treatment, including transvaginal follicular ultrasound scans and measurements of serum estradiol and LH levels, can usually be conducted in a subspecialist reproductive endocrinology practice. Because of the cost and logistic requirements involved, the method is generally reserved for patients in whom less complicated methods fail to provide the necessary information and for women who are at a high risk for developing serious complications such as severe ovarian hyperstimulation syndrome (OHSS) and multiple pregnancy.23 In the past, it was generally recommended that patients receiving clomiphene citrate treatment be examined before starting each new treatment cycle to ensure that there was no significant residual ovarian enlargement or ovarian follicular cysts. However, it appears that small residual follicular cysts usually do not expand during continued treatment.31 Consequently, it is unnecessary to perform “baseline” ultrasound examinations before each new treatment cycle. However, it is reasonable to withhold treatment when symptoms suggest the presence of a large cyst or gross residual ovarian enlargement.23
Outcome of Clomiphene Citrate Treatment Clomiphene citrate treatment has been reported to successfully induce ovulation in 60% to 80% of properly selected women. More than 70% of those who ovulate respond at the 50-mg or 100-mg dosage level. In young anovulatory women in whom anovulation is the sole reason preventing them from conceiving, cumulative conception rates between 60% and 70% are observed after up to three successfully induced ovulatory cycles, and 70% to 85% after five cycles. Overall, cycle fecundity is approximately 15% in women who ovulate in response to treatment.21 In the reality of daily clinical practice, clomiphene citrate induction of ovulation usually results in much lower pregnancy rates, particularly in a subspecialty referral infertility practice. Important factors that adversely affect treatment outcome are increased age (particularly older than age 35), presence of other treated or untreated infertility factors, and increasing duration of infertility.32 Amenorrheic women are more likely to conceive than oligomenorrheic women, probably because those who already ovulate, albeit inconsistently (oligomenorrheic), are more likely to have other coexisting infertility factors. Generally speaking, failure to conceive within six clomiphene citrate-induced
ovulatory cycles is a clear indication to expand the diagnostic evaluation to exclude other factors, change the overall treatment strategy, or both.23
Adverse Effects and Risks of Clomiphene Citrate Clomiphene citrate is generally well-tolerated. Some side effects are relatively common, but rarely are they persistent or severe enough to threaten completion of treatment. Although clomiphene citrate treatment does have intrinsic risks, they are typically modest and manageable. Adverse effects are generally divided into the side effects related to clomiphene citrate itself and the adverse effects related to induction of ovulation in general. Side Effects
Hot flashes due to the antiestrogenic property of clomiphene citrate are dose-dependent and occur in approximately 10% of clomiphene citrate-treated women. Symptoms are transient, rarely severe, and typically resolve soon after treatment ends. Visual disturbances, including blurred or double vision, scotomata, and light sensitivity, are generally uncommon (<2% prevalence) and reversible. However, there are isolated reports of persistent symptoms long after treatment is discontinued with more severe complications such as optic neuropathy. Whenever visual disturbances are identified, treatment should be stopped and alternative methods of ovulation induction should be considered. Less specific side effects include breast tenderness, pelvic discomfort, and nausea, all observed in 2% to 5% of clomiphene citrate-treated women.33 In addition, there are relatively common reports of premenstrual syndrome-type symptoms in women on clomiphene citrate.34 Congenital Anomalies
There is no evidence that clomiphene citrate treatment increases the overall risk of birth defects or of any specific malformation. Several large series have examined the question and have drawn the same conclusion.35,36 Earlier suggestions that the incidence of neural tube defects might be higher in pregnancies conceived during clomiphene citrate treatment have not been confirmed by more recent studies.37 A small study of pregnancy outcome in women inadvertently exposed to clomiphene citrate during the first trimester also found no increase in the prevalence of congenital anomalies.38 Pregnancy Loss
More than one study has suggested that pregnancies resulting from clomiphene citrate treatment are at increased risk of spontaneous abortion compared to spontaneous pregnancies. A study reviewed outcomes of 1744 clomiphene pregnancies compared to outcomes of 3245 spontaneous pregnancies.39 In this study, pregnancy loss was classified as either clinical if a sac was seen on ultrasound or if it occurred after 6 weeks’ gestation, or preclinical if a quantitative human chorionic gonadotropin (hCG) was greater than or equal to 25 IU/L and no sac was seen or abortion occurred earlier. In this study, when preclinical and clinical were considered together, the overall incidence of spontaneous abortion was slightly higher for clomiphene pregnancies than for spontaneous pregnancies (23.7% versus 20.4%). When considered separately, preclinical spontaneous abortions were
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Section 6 Infertility and Recurrent Pregnancy Loss also increased by clomiphene citrate overall (5.8% versus 3.9%) and for women at least 30 years old (8.0% versus 4.9%), but not for those younger than age 30 (3.7 versus 3.0%). In contrast, when clinical abortions were considered separately, clomiphene citrate did not increase the overall rate (18.0% versus 16.4%), but the rate was increased for women younger than age 30 (15.9% versus 11.2%). More recent studies looking at rate of spontaneous miscarriage in 62,228 clinical pregnancies resulting from ART procedures initiated in 1996 to 1998 in U.S. clinics also found that spontaneous miscarriage risk was increased among women who used clomiphene citrate.40,41 However, the results of these studies are not considered to be conclusive. The pregnancy loss seen in women after clomiphene treatment may actually be related to other comorbidities in these patients, such as insulin resistance, other genetic factors related to PCOS or unexplained infertility, endometriosis, and advancing maternal age.42 Antiestrogenic Effects and Fertility
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Clomiphene citrate treatment is associated with antiestrogenic effects that might have adverse effects on fertility. Because of the relatively long half-life of clomiphene citrate isomers, clomiphene citrate exerts undesirable and unavoidable antiestrogenic effects on the endocervix, endometrium, ovary, ovum, and embryo. Numerous studies in women and in various model systems have described adverse effects on the quality or quantity of cervical mucus, endometrial growth and maturation, follicular or corpus luteum steroidogenesis, ovum fertilization, and embryo development. These adverse effects are believed to explain the “discrepancy” between the ovulation and conception rates observed in clomiphene citrate-treated patients. These effects appear to be more apparent at higher doses or after longer durations of treatment. It has been suggested that treatment with exogenous supplemental estrogen may help to minimize or negate these effects.43,44 However, there is little compelling evidence to support any beneficial effect of estrogen replacement to reverse these peripheral antiestrogenic effects.23 Clomiphene citrate treatment has been shown to affect the quality and quantity of cervical mucus production as well as the structure of the endometrium.45–47 However, cervical mucus score (based on quantity and quality) has not been found to be of proven prognostic value on the treatment outcome (i.e., achievement of pregnancy). The endometrium is believed to be one of the most important targets of the antiestrogenic effect of clomiphene citrate and may explain a large part of the lower pregnancy rate and the possible higher miscarriage rate with clomiphene citrate. Successful implantation requires a receptive endometrium, with synchronous development of glands and stroma.48 Studies have reported conflicting effects of clomiphene citrate on the endometrium45–47,49–51 possibly due to different methodology used for endometrial assessment. However, a recent study has prospectively applied morphometric analysis of the endometrium, a quantitative and objective technique to study the effect of clomiphene citrate on the endometrium in a group of normal women. In this study, clomiphene citrate was found to have a deleterious effect on the endometrium, demonstrated by a reduction in glandular density and an increase in the number of vacuolated cells.51 In addition, a reduction in endo-
metrial thickness below the level thought to be needed to sustain implantation was found in up to 30% of women receiving clomiphene citrate for ovulation induction or for unexplained infertility.45 This observation has been confirmed by other studies.46,47 Decreased uterine blood flow during the early luteal phase and the peri-implantation stage has been suggested to explain, at least in part, the poor outcome of clomiphene citrate treatment.51 Other investigators have suggested the presence of other unrecognized factors associated with clomiphene citrate treatment failure.52–54 Moreover, there is some evidence for a direct negative effect of clomiphene citrate on fertilization, and on early mouse and rabbit embryo development.55,56 In addition, there have been reports of low-quality oocytes associated with clomiphene citrate treatment. However, the negative effects of clomiphene citrate in some animal studies have not been confirmed by others,53,54 and at present it is unclear if there are adverse direct effects of clomiphene citrate on human oocytes and human embryo development. Because of the above-mentioned evidence for adverse peripheral antiestrogenic effects of clomiphene citrate treatment, several investigators tried to reverse these effects by administering estrogen concomitantly with clomiphene citrate treatment. Some investigators have reported increased endometrial thickness and improved pregnancy rates with this approach57,58; others have reported no benefit44 or even a deleterious effect of estrogen administration.59 Another approach has been to administer clomiphene citrate earlier during the menstrual cycle rather than starting on day 5,60 in the hopes of allowing the antiestrogenic effect to wear off to some extent before ovulation and implantation. In view of the long half-life of clomiphene citrate isomers, this approach is unlikely to be successful. A third method has been to combine another SERM such as tamoxifen, which has more estrogen agonistic effect on the endometrium with clomiphene citrate or to use tamoxifen as an alternative to clomiphene citrate.61 However, none of these strategies have proved to be completely successful in avoiding the peripheral antiestrogenic effects of clomiphene citrate. A more recent publication has suggested that high-dose soy isoflavones may be able to overcome the antiestrogenic effect of clomiphene citrate on the endometrium.62 This report remains to be confirmed by other investigators. To summarize, from the available evidence and accumulated clinical experience, it is difficult to conclude the exact significance of adverse antiestrogenic effects on pregnancy outcome in clomiphene citrate-treated women. It seems that individual variability exists regarding sensitivity to the peripheral antiestrogenic effects of clomiphene citrate, likely because of the complexity of estrogen receptor replenishment and activation, and individual differences in the pharmacokinetics of clomiphene citrate. The discrepancy in the success rates in achieving pregnancy between women with unexplained infertility and women with PCOS in response to clomiphene citrate treatment (higher rates in PCOS women) suggests that PCOS women may be less vulnerable to the antiestrogenic effects of clomiphene citrate on peripheral tissues. Recent findings of differences in the expression levels of receptors (androgen receptor, estrogen receptor α and β, progesterone receptor) and cofactors in human endometrium and myometrium in PCOS patients support this hypothesis.63 For example, the p160 family of steroid receptor coactivators,
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Chapter 37 Induction of Ovulation known to facilitate the action of steroid receptors throughout the menstrual cycle, was found to be overexpressed in the endometrium of women with PCOS.80 However, the presence of infertility factors, rather than an increased sensitivity to the antiestrogenic effects of clomiphene citrate, in non-PCOS women may explain the less favorable outcome of clomiphene citrate treatment.
FAILURE OF CLOMIPHENE CITRATE TREATMENT
and exogenous gonadotropins), and laparoscopic ovarian drilling. Steroids are no longer used for ovulation induction except for properly diagnosed CAH. It is obvious that the choice of treatment should not be arbitrary, but rather should be based on the patient’s history, the results of laboratory evaluation, and observations in previous unsuccessful clomiphene citrate treatment cycles. We provide a brief overview of the use of these agents in conjunction with ovulation induction in PCOS patients in this chapter.
Insulin-Sensitizing Agents Etiologies When considering clomiphene citrate treatment we can define two groups of treatment failures. The first group, clomiphene ovulation failure (clomiphene resistance), includes patients who fail to ovulate with clomiphene citrate treatment. The second group, clomiphene pregnancy failure, includes patients who ovulate with clomiphene citrate treatment but fail to achieve pregnancy. This second group also includes women with ovulatory infertility who do not achieve pregnancy after clomiphene citrate treatment. Clomiphene Ovulation Failure
The two main reasons for clomiphene ovulation failure are insulin resistance (women with PCOS) and inappropriate indication for clomiphene citrate (e.g., use in women with WHO group I or III anovulation or women with ovulatory dysfunction due to medical disorders that require specific treatments, such as thyroid disorders, congenital adrenal hyperplasia [CAH], and hyperprolactinemia). Clomiphene Pregnancy Failure
The reasons for clomiphene pregnancy failure (women who ovulate in response to clomiphene citrate but do not achieve pregnancy) may be related to a wide variety of underlying infertility factors, such as male factor infertility, endometriosis, undiagnosed tubal factor, or endometrial receptivity factors. However, the success of many of these women in achieving pregnancy with alternative ovarian stimulation protocols using injectable gonadotropins or aromatase inhibitors supports the hypothesis that persistent antiestrogenic effects associated with clomiphene citrate might play a major role in the discrepancy between ovulatory rates and pregnancy rates.64–66
ALTERNATIVE APPROACHES FOR CLOMIPHENE FAILURES Some women who are refractory to standard clomiphene citrate treatment regimens will ovulate in response to alternative regimens of clomiphene citrate, including longer duration or higher doses of clomiphene citrate treatment. For example, an 8-day treatment regimen or doses of 200 to 250 mg/day can be effective when shorter courses of therapy fail. However, longer treatment and higher doses are expected to be associated with more antiestrogenic effects and reduced chances for achieving pregnancy even though ovulation is achieved.23 Several adjunctive treatments have been suggested to overcome resistance to clomiphene citrate, including the use of insulin-sensitizing agents (e.g., metformin), exogenous hCG and combinations (sequential treatment with clomiphene citrate
Insulin resistance and hyperinsulinemia are recognized features of PCOS. Hyperinsulinemia contributes significantly to hyperandrogenism and chronic anovulation. It is logical that agents that improve insulin action in the body (insulin sensitizers) will help infertile PCOS women with insulin resistance to achieve ovulation by lowering their hyperinsulinemia. This is particularly true in PCOS patients who fail to ovulate with clomiphene citrate treatment. De Leo and colleagues reviewed the use of insulin-lowering agents in the management of PCOS,67 with extensive discussion of the effect of these agents on endocrine, metabolic, and reproductive functions. Although it is believed that the endocrine and reproductive benefits observed during treatment with insulin sensitizers in PCOS women are due to improving insulin resistance, insulin sensitizers may work through other mechanisms to achieve ovulation in these patients. One such mechanism is a direct effect on ovarian steroidogenesis. There is evidence that the insulin sensitizers, metformin and thiazolidinediones, can modulate steroid production through direct suppression of steroidogenesis enzymes. Troglitazone was found to inhibit progesterone production by human luteinized granulosa cells and to reduce androgen production by rat theca cells.68,69 It was also found to directly inhibit 3β-hydroxysteroid dehydrogenase, leading to decreased progesterone secretion by porcine granulosa cells.70 Troglitazone, and presumably other thiazolidinediones, inhibits cholesterol biosynthesis in Chinese hamster ovary cells71 and aromatase in human granulosa cells.72 Metformin
Several studies demonstrated that treatment alone with the insulin-sensitizing agent metformin could restore menses and cyclic ovulation in many amenorrheic PCOS women.16,73 This led some to advocate metformin as primary therapy in infertile PCOS women with insulin resistance (1000 to 2000 mg/day in divided doses) and add clomiphene citrate only in those who fail to respond. However, the relatively greater costs per cycle compared to clomiphene citrate, as well as the complexity of metformin treatment and the frequency of significant gastrointestinal side effects (e.g., nausea, vomiting, diarrhea) made others prefer to reserve metformin treatment for those who first prove resistant to clomiphene citrate. Caution should be used in prescribing these drugs to women with potential renal or liver disease. It is recommended that a creatinine level and liver function tests be obtained before starting therapy.73 Unfortunately, most of the studies published so far on the use of metformin in PCOS women were not randomized. Even the randomized trials included a small number of patients, which prevented definitive conclusions. However, meta-analysis
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Section 6 Infertility and Recurrent Pregnancy Loss of the combined results of prior clinical trials concluded that metformin is effective in achieving significant rates of ovulation and pregnancy in women with PCOS.It is important to note the difference between achieving ovulation and achieving a pregnancy. Effectiveness of Metformin
A recent Cochrane meta-analysis showed that metformin is effective in achieving ovulation in women with PCOS with an odds ratio (OR) of 3.88 (confidence interval [CI], 2.25–6.69) for metformin versus placebo and 4.41 (CI, 2.37–8.22) for metformin and clomiphene citrate versus clomiphene citrate alone. An analysis of pregnancy rates suggests a significant treatment effect for metformin and clomiphene citrate (OR, 4.40; CI, 1.96–9.85). The authors concluded that metformin is an effective treatment for anovulation in women with PCOS, and its choice as a first-line agent seems justified.73 A more recent systematic review of metformin use in women with PCOS included cohort and randomized, controlled trials of metformin versus placebo, metformin versus clomiphene citrate, and metformin plus clomiphene citrate versus placebo plus clomiphene citrate. The authors found metformin to be 50% better than placebo for ovulation induction (RR, 1.50; 95% CI, 1.13–1.99). However, metformin alone was not of confirmed benefit versus placebo for achievement of pregnancy (RR, 1.07; CI, 0.20–5.74) whereas metformin plus clomiphene citrate was threefold superior to clomiphene citrate alone for ovulation induction (RR, 3.04; CI, 1.77–5.24) and pregnancy (RR, 3.65; CI, 1.11–11.99). The authors concluded that metformin is effective for ovulation and metformin plus clomiphene citrate appears to be very effective for achievement of pregnancy compared to clomiphene citrate alone.74 In a prospective, randomized, double-blind, controlled clinical trial comparing clomiphene citrate and metformin as the first-line treatment for ovulation induction in nonobese anovulatory women with PCOS, it was shown that metformin 850 mg twice daily was associated with a higher pregnancy rate than clomiphene citrate 150 mg for 5 days from the third day of a progesterone withdrawal bleed (69% versus 34%).75 There was also a tend toward a higher birth rate. In a recent multicenter randomized placebo controlled trial, it was shown that metformin did not increase the probability of ovulation or pregnancy when added to clomiphene citrate as a first-line treatment of infertile women with PCOS.76 Therefore, in most cases clomiphene citrate is considered the drug of choice in the treatment of anovulatory infertility of PCOS. Metformin can be added if clomiphene fails to induce ovulation. Alternative Insulin-Sensitizing Agents
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Other insulin-sensitizing agents such as the thiazolidinediones (troglitazone, rosiglitazone, and pioglitazone) and chiroinositol77–84 have been used in small clinical trials to achieve ovulation in PCOS women with insulin resistance. However, because of the higher safety profile, longer clinical experience, and lower cost of metformin, the other insulin sensitizers should be reserved for cases resistant to metformin treatment.85 Finally, before concluding this section on the use of insulin sensitizers in infertile women with PCOS, it is necessary to stress the importance of other nonpharmacologic approaches to improve insulin action and reduce insulin resistance, including dietary factors, weight loss, and exercise. The use of insulin-sensitizing agents should be as an adjuvant to these nonpharmacologic approaches.
Human Chorionic Gonadotropin The administration of hCG during clomiphene citrate treatment aims at either substituting (before the occurrence of the endogenous LH surge) or supporting the endogenous LH surge. This may be particularly useful for timing insemination or recommending the optimum fecundity period for intercourse. A number of clinical studies have examined the efficacy of using exogenous hCG as a surrogate LH surge in women who fail to ovulate in response to clomiphene citrate alone.31,86,87 Clinical studies in anovulatory infertile women have demonstrated that on the day of the spontaneous LH surge in successful clomiphene citrate-induced ovulatory cycles, mean diameter of the lead follicle ranges between 19 and 30 mm (median diameter, 25 mm).87 Given that the average growth rate of the preovulatory follicle over the days immediately preceding ovulation is approximately 2 mm/day, the LH surge can occur during an interval of time of approximately 5 days. Normally, the preovulatory follicle triggers its own ovulation at the peak of maturity by generating and maintaining estrogen levels above the threshold required, inducing the LH surge. Timing of the spontaneous LH surge is therefore always optimal, and that of hCG administration can never be more than an educated guess. In those uncommon instances in which hCG treatment may be effective and is necessary, it is probably best postponed until the lead follicle reaches or exceeds 20 mm in mean diameter.23 Occasionally, a couple may require both clomiphene citrate treatment and IUI because of anovulation and a coexisting male factor. Clearly, accurate timing of the insemination is crucial to the success of treatment. Effectiveness
In a review of 2000 consecutive completed ovarian stimulation cycles with timed intercourse or IUI, the occurrence of an LH surge was associated with a higher pregnancy rate compared to hCG administration with clomiphene citrate treatment, but a lower pregnancy rate compared to hCG administration with gonadotropin treatment, suggesting that awaiting occurrence of the LH surge might be associated with a better outcome with clomiphene citrate treatment.88 Disadvantages
The administration of hCG does have distinct potential disadvantages and consequences. This is because to properly time its administration, follicular development should be monitored with serial transvaginal ultrasound examinations that are costly and generally unnecessary. This sophisticated approach contradicts the major benefit of clomiphene citrate ovulation induction (i.e., simplicity and low cost). Moreover, it is difficult to determine when best to administer exogenous hCG, even in carefully monitored cycles.
Gonadotropins Clomiphene citrate-resistant anovulatory women who ultimately require exogenous gonadotropins to achieve ovulation might benefit from a trial of sequential clomiphene citrate and gonadotropin therapy. Sequential clomiphene citrate and gonadotropin (hMG or FSH) therapy has become increasingly used to produce ovarian superovulation for patients who fail clomiphene citrate treatment.89,90
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Chapter 37 Induction of Ovulation The value of adding clomiphene citrate during ovarian superovulation is to decrease the FSH dose required for optimum stimulation. However, care in monitoring must be taken because clomiphene citrate use may be associated with peripheral antiestrogenic effects, offsetting the FSH dose reduction benefit.91
Laparoscopic Ovarian Drilling Whether ovarian drilling is a valid option for clomiphene citrateresistant women with PCOS has been a matter of intense debate. The technique involves laparoscopic cautery, diathermy, or laser vaporization of the ovaries at multiple sites, the objective being to decrease circulating and intraovarian androgen levels by reducing the volume of ovarian stroma (modern version of the classic ovarian wedge resection operation). Ovarian drilling is reported to result in resumption of spontaneous ovulation or at least restore sensitivity to clomiphene citrate treatment. Formation of postoperative adhesions that may compromise fertility is common.92 Serum testosterone concentrations typically fall by approximately 40% to 50%, at least for a period of months. About 70% to 90% of properly selected candidates will ovulate after drilling, and 50% to 80% of those will conceive. Consequently, ovarian drilling is perhaps best reserved for clomiphene citrate-resistant women in whom cost or logistic considerations effectively preclude alternative treatments (e.g., exogenous gonadotropins).23 Ovarian drilling does not seem to improve the metabolic derangement of insulin resistance and lipid dysfunction.93
Aromatase Inhibitors Clomiphene citrate is the mainstay of ovulation induction therapy as long as no other alternative is available that has the same advantages of oral administration, limited monitoring requirements, mild side effects, and a comparatively low cost and risk of multiple pregnancy. However, treatment should use the lowest effective dose, empirically determined, and should rarely exceed six cycles of therapy. Failure to conceive despite successful clomiphene citrate-induced ovulation is an indication to expand evaluation to exclude other coexisting infertility factors or to change the overall treatment strategy. In patients with PCOS, metformin is definitely an important next step and perhaps a first step. However, other drugs are available as options. Aromatase Description
Aromatase is a microsomal member of the cytochrome P450 hemoprotein-containing enzyme complex superfamily (P450arom, the product of the CYP19 gene). Aromatase catalyzes the ratelimiting step in the production of estrogens, that is, the conversion of androstenedione and testosterone via three hydroxylation steps to estrone and estradiol, respectively.94 Aromatase activity is present in many tissues, such as the ovaries, the brain, adipose tissue, muscle, liver, breast tissue, and in malignant breast tumors. The main sources of circulating estrogens are the ovaries in premenopausal women and adipose tissue in postmenopausal women.95 Aromatase is a good target for selective inhibition because estrogen production is a terminal step in the biosynthetic sequence (Table 37-1).
Types of Aromatase Inhibitors
A large number of aromatase inhibitors have been developed over the past 30 years with the most recent, third-generation aromatase inhibitors licensed mainly for breast cancer treatment in postmenopausal women.96 Aromatase inhibitors have been classified in different ways: into steroidal and nonsteroidal and, according to the stage of development, into first-, second-, and third-generation groups. The first aromatase inhibitor to be used clinically was aminoglutethimide, which induces a medical adrenalectomy by inhibiting many other enzymes involved in steroid biosynthesis.97 Although aminoglutethimide is an effective hormonal agent in postmenopausal breast cancer, its use is complicated by the need for concurrent corticosteroid replacement, in addition to side effects such as lethargy, rashes, nausea, and fever that result in 8% to 15% of patients stopping treatment.98 The lack of specificity and unfavorable toxicity profile of aminoglutethimide led to the search for more specific aromatase inhibitors. In addition, the earlier aromatase inhibitors were not able to completely inhibit aromatase activity in premenopausal patients. The third-generation aromatase inhibitors commercially available include two nonsteroidal preparations, anastrozole and letrozole, and a steroidal agent, exemestane.99–101 Anastrozole and letrozole are available for clinical use in North America, Europe, and other parts of the world for treatment of postmenopausal breast cancer. These triazole (antifungal) derivatives are reversible, competitive aromatase inhibitors with considerably greater intrinsic potency than aminoglutethimide (more than 1000 times), and at doses of 1 to 5 mg/day, inhibit estrogen levels by 97% to more than 99% down to concentrations below detection by most sensitive immunoassays. Aromatase inhibitors are completely absorbed after oral administration, with a mean terminal half-life of approximately 45 hours (range, 30 to 60 hours) with clearance from the systemic circulation mainly by the liver. Mild gastrointestinal disturbances account for most of the adverse events, although these have seldom limited therapy. Other adverse effects including asthenia, hot flashes, headache, and back pain are based on studies in postmenopausal women.99–101 Mechanism of Action for Ovulation Induction
Recently, success in using aromatase inhibitors for induction of ovulation has been reported.102–109 Several hypotheses have been postulated for the mechanisms underlying the effectiveness of these medications in ovulation induction.110 Table 37-1 Potential Advantages of Using an Aromatase Inhibitor for Induction of Ovulation High pregnancy rates Monofollicular ovulation in most anovulatory patients High safety due to short half-life and few adverse effects Reduced rate of multiple pregnancy Reduced risk of severe ovarian hyperstimulation syndrome Reduced FSH dose required for controlled ovarian stimulation Improved response to FSH in poor responders Low cost of treatment (average, $30–$100 per cycle) Convenience of administration: oral route, different regimens, including single-dose regimen
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Section 6 Infertility and Recurrent Pregnancy Loss Central Hypothesis
It might be possible to mimic the action of clomiphene citrate, without depletion of the estrogen receptors, by administration of an aromatase inhibitor in the early part of the menstrual cycle. There is evidence that both circulating estrogen (produced by the ovaries) and locally produced estrogen (produced in the brain) exert negative feedback on the release of gonadotropins.111–114 Blocking estrogen production from all sources by inhibiting aromatization would release the hypothalamic-pituitary axis from estrogen-negative feedback, thereby increasing gonadotropin secretion and resulting in stimulation of ovarian follicles. The selective nonsteroidal aromatase inhibitors have a relatively short half-life (approximately 45 hours) compared to clomiphene citrate, and would be ideal for this purpose because they are eliminated from the body rapidly.115,116 In addition, no adverse effects on estrogen target tissues is expected, because no estrogen receptor down-regulation occurs, in contrast to the estrogen receptor depletion observed in clomiphene citratetreated cycles. In addition to the primary response of gonadotropins to diminished estrogen-negative feedback during aromatase inhibitor use, another centrally mediated mechanism of action may be possible independent of GnRH-mediated gonadotropin release. Accumulating evidence suggests that estrogen can modulate the activin/inhibin/follistatin system,117–120 leading to FSH production through a direct effect on the pituitary gonadotropes. Activins are produced by a wide variety of tissues, including the pituitary gland,121 and stimulate synthesis of FSH by a direct action on the gonadotropes.122 Follistatin, also produced by the pituitary gland, is an activin-binding protein and may decrease FSH synthesis by sequestering activin.123 Estrogen, through activin suppression,124 was found to selectively suppress FSH, but not LH, production through a GnRH-independent mechanism.124–126 In women with PCOS, relative oversuppression of FSH may be the result of excessive androgen produced from the ovary being converted to estrogen by aromatization in the brain. The aromatase inhibitors suppress estrogen production in both the ovaries and the brain. In the case of PCOS, therefore, aromatase inhibitors should result in a robust increase in FSH release and subsequent follicle stimulation and ovulation. The actual FSH release is likely to be blunted by the high circulating inhibin found in PCOS patients127–130 that would not be altered by aromatase inhibition. The raised concentrations of inhibin A and B is probably due to the increased number of small antral follicles.129 In addition, because aromatase inhibition does not antagonize estrogen receptors in the brain, the initiation of follicle growth accompanied by increasing concentrations of both estradiol and inhibin results in a normal secondary feedback loop that limits FSH response, thereby avoiding the risk of high multiple ovulation and OHSS. Peripheral Hypothesis
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A second hypothesis to explain the mechanism of action of the aromatase inhibitors in ovarian stimulation involves an increased follicular sensitivity to FSH. This may result from temporary accumulation of intraovarian androgens, because conversion of androgen substrate to estrogen is blocked by aromatase inhibition. Recent data support a stimulatory role for androgens in early follicular growth in primates.131 Testosterone was found to augment follicular FSH receptor expression in primates, suggesting
that androgens promote follicular growth and estrogen biosynthesis indirectly by amplifying FSH effects.132,133 Also, androgen accumulation in the follicle stimulates insulin-like growth factor I (IGF-I), which may synergize with FSH to promote folliculogenesis.134–137 It is likely that women with PCOS already have a relative aromatase deficiency in the ovary, leading to increased intraovarian androgens,138,139 which leads to the development of multiple small follicles responsible for the polycystic morphology of the ovaries. The androgens may also increase FSH receptors, making these PCOS ovaries exquisitely sensitive to an increase in FSH either through exogenous administration of gonadotropins (hence the high risk of OHSS) or through endogenous increases in FSH as a result of decreased central estrogen feedback induced by aromatase inhibition. In the latter case, a relatively small rise in FSH, because of a normal inhibin/estrogen feedback loop, generally leads to monofollicular ovulation, thus avoiding the occurrence of OHSS. Another part of the peripheral hypothesis involves estrogen receptors in the endometrium. It is possible that aromatase inhibition, with suppression of estrogen concentrations in the circulation and in peripheral target tissues, results in up-regulation of estrogen receptors in the endometrium, leading to rapid endometrial growth once estrogen secretion is restored. Estrogen has been shown to decrease the level of its own receptor by stimulating ubiquitination of estrogen receptors, resulting in rapid degradation of the receptors. In the absence of estrogen, ubiquitination is decreased, allowing up-regulation of the estrogen receptor and increasing sensitivity to subsequent estrogen administration.140 This could increase endometrial sensitivity to estrogen, resulting in more rapid proliferation of endometrial epithelium and stroma and improved blood flow to the uterus and endometrium.141 As a result, normal endometrial development and thickness occur by the time of follicular maturation, even in the face of the observed lower than normal estradiol concentrations in aromatase inhibitor-treated cycles.102–109 Potential Advantages Compared to Clomiphene Citrate
The significantly shorter half-life (approximately 45 hours) of the third-generation aromatase inhibitors compared to clomiphene citrate allows rapid elimination from the body.115,116 Because no estrogen receptor down-regulation occurs, no adverse effects on estrogen target tissues are observed, as is frequently the case with clomiphene citrate. Aromatase inhibitors are, therefore, an interesting alternative to clomiphene citrate, particularly in cases with recurrent clomiphene citrate failure, as explained earlier in this chapter. However, in the case of clomiphene citrate resistance (failure to ovulate) due to severe insulin resistance or the use of clomiphene citrate for inappropriate indications (e.g., hypothalamic amenorrhea or ovarian failure), the use of an aromatase inhibitor is also unlikely to be successful. The correction of insulin resistance with an insulin sensitizer is the logical approach in patients with insulin resistance. Alternative treatments should be considered for other problems, such as exogenous gonadotropin injection in hypothalamic anovulation patients and oocyte donation for cases with ovarian failure. In recent years, evidence supporting the success of aromatase inhibitors in infertility treatment has been accumulating.102–109 Most of the studies used letrozole. However, anastrozole, another third-generation aromatase inhibitor similar to letrozole, was used in other studies.107,142,143 It is currently not known whether
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Chapter 37 Induction of Ovulation there are any clinically significant pharmacologic differences between letrozole and anastrozole.144 Recent safety studies have found anastrozole to have no teratogenic or clastogenic effects in animal embryo development.145,146 Aromatase Inhibitors and Exogenous Gonatrotropins
Aromatase inhibitors may be used alone for induction of ovulation, or as adjuvants in conjunction with exogenous FSH or other medications to improve the outcome of ovulation induction. A major advantage of an aromatase inhibitor used alone is the ability to achieve restoration of monofollicular ovulation in anovulatory infertility (e.g., PCOS) with either multiple102,103,105 or single-dose147 regimens of aromatase inhibitor early in the menstrual cycle. A single-dose regimen has the benefit of convenience but the potential disadvantage of increasing side effects from administration of a larger dose. However, single doses several times higher than the doses reported for ovulation induction have been administered with no adverse effects observed.148,149 An aromatase inhibitor may also be used in conjunction with FSH injections to increase the number of preovulatory follicles that develop and to improve the outcome of treatment. Giving an aromatase inhibitor together with FSH resulted in a significant reduction in the dose of FSH required for optimum ovarian stimulation105 even in poor responders.106 The additional effect of aromatase inhibitors to reduce the supraphysiologic levels of estrogen seen with the development of multiple ovarian follicles may also improve treatment outcome.110 To summarize, the aromatase inhibitor when used alone results in a predictable response with the development of one or two mature follicles and a significantly reduced risk for ovarian hyperstimulation and multiple gestations.150 To achieve higherorder multiple ovulation, the addition of FSH to the aromatase inhibitor seems to be necessary. Aromatase Inhibitors for Endometriosis-Related Infertility
The exciting data on the expression of aromatase enzyme in endometriotic tissues with the significant role of locally produced estrogen on endometriosis progression151,152 suggests a benefit of aromatase inhibitors in endometriosis-related infertility. The inhibition of local estrogen production in endometrial implants and the lower peripheral estrogen levels associated with the use of aromatase inhibition for ovulation induction are expected to protect, to some degree, against progression of endometriosis during infertility treatment. Concerns About Aromatase Inhibitors
There are concerns about using aromatase inhibitors for induction of ovulation, including potential adverse effects of aromatase inhibitors resulting from low follicular estrogen levels and a temporary increase in ovarian androgens. In clinical use, nonsteroidal aromatase inhibitors are generally well tolerated. The main adverse events observed are hot flushes, gastrointestinal events (nausea and vomiting), and leg cramps. Overall, very few patients withdrew from first- or second-line comparative Phase III trials because of drug-related adverse events with aromatase inhibitors.153,154 These adverse effects were observed in older women with advanced breast cancer who were given the aromatase inhibitors on a daily basis over several months. Fewer adverse effects would be expected in the usually healthy younger
women administered a short course of aromatase inhibitor for induction of ovulation. The question whether low or very low intrafollicular estrogen is compatible with follicular development, ovulation, and corpus luteum formation has been reviewed before.155 Markedly reduced to absent intrafollicular concentrations of estrogen are known to be compatible with follicular “expansion,” retrieval of fertilizable oocytes, and apparently normal embryo development.156–160 The rapid clearance of the aromatase inhibitors, the reversible nature of enzyme inhibition, and elevated levels of FSH, which induces new expression of aromatase enzyme, are factors that limit accumulation of androgens and result in increasing estrogen production.
ADVERSE EFFECTS AND CONCERNS REGARDING ORAL OVULATION INDUCTION AGENTS Multiple Gestations In the past decade, the significant increase in the incidence of multiple births in most countries is almost entirely the result of the use of gonadotropins and other agents for induction of ovulation.161 According to the National Vital Statistics Reports for 2001, the rate of twinning has increased 33% since 1990 and 59% since 1980. Furthermore, the rate of triplets and higherorder multiples has increased more than 400% since 1980.162 In 2001, 1.6% of singletons, 11.8% of twins, 36.7% of triplets, 64.5% of quadruplets, and 78.6% of quintuplets were delivered before 32 completed weeks of gestation.162 Even more noteworthy, the incidence of extreme prematurity (delivery before 28 weeks) for both triplets and quadruplets may be as high as 14%.163,164 The increased incidence of maternal and neonatal complications associated with multiple pregnancies has been well documented.165,166 Review of data from the National Center for Health Statistics reveals that twins are 4 times more likely than singletons to die within the first month of life, and triplets are 10 times more likely to die in this time. Hospital costs for each twin or triplet infant can be twice or three times that of a singleton, and lifetime costs to the healthcare system and community may be 100 to 200 times that of a singleton.167 After controlling for variables known to affect hospital charges, the predicted total charges to the family in 1991 for a singleton delivery were $9,845, as compared with $37,947 for twins ($18,974 per baby) and $109,765 for triplets ($36,588 per baby).167 Unfortunately, there is substantial pressure from patients in infertility treatment programs to increase their success rates. Among the strategies used are increasing the number of ovarian follicles matured by the administration of exogenous gonadotropins during induction of ovulation and increasing the number of embryos or gametes transferred in cases of IVF. Each of these strategies aims at increasing the percentage of successful pregnancies but also substantially increases the likelihood of multiple pregnancies. That increase, in turn, drives obstetric and neonatal charges higher. Many fear that decreasing the number of follicles stimulated or the number of embryos transferred to reduce the number of multiple pregnancies will lead to lower success rates and an increase in the number of cycles of treatment needed to achieve a pregnancy.
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However, the European experience with limiting the number of embryos transferred to two or even to single embryo transfer in Scandinavia in good-prognosis patients has not demonstrated a substantial drop in pregnancy rates while reducing the twin rate to less than 10%.168 More difficult is the problem of multiple pregnancy after ovulation induction with IUI. In the United States reported rates of multiple pregnancies greater than 30% result from ovarian stimulation, most commonly associated with IUI.169 The incidence of multiple pregnancy ranges from 10% to 15% with gonadotropins alone and from 15% to 29% with gonadotropins and IUI.170 With clomiphene citrate treatment, multifollicular development is relatively common and the risk of multiple gestation is clearly increased (approximately 8%). The overwhelming majority of multiple pregnancies that result from clomiphene citrate treatment are twin gestations; triplet and higher-order pregnancies are rare but may indeed occur.171 Several recent national studies of the increasing incidence of multiple pregnancies indicate that the vast majority of higherorder multiple gestations (63% to 80%) are a direct result of ovarian stimulation with gonadotropins, mainly FSH with IUI rather than with IVF with embryo transfer.165,172 There has been a consistent decrease in the number of embryos transferred per cycle and a drop in the percentage of pregnancies with three or more fetuses since 1997 in the United States.172 It is obvious that the best strategy is prevention of the occurrence of multiple pregnancies rather than dealing with the problem after its occurrence (e.g., multifetal pregnancy reduction). Selective fetal reduction presents an ethical problem for many couples, entails the risk of losing all fetuses being carried, and increases psychological stress for couples who have struggled through years of infertility.173,174 Other strategies that have focused on the prevention of premature delivery through intensive antenatal monitoring and interventions have been only partially successful in controlling the complications of multiple pregnancies.175 Each of these proposed methods of improving the outcome of multiple pregnancies relies on post hoc measures used after multiple gestation has been established. As mentioned above, a preferable and more economical solution would be to avoid the conception of multiple fetuses. Several studies have shown that the number of multiple pregnancies can be decreased by the more judicious use of ovarian stimulation agents, by increased monitoring,176,177 and even by the use of less common but safer agents to induce ovulation, such as pulsatile GnRH.170 These strategies aim at reducing the incidence of multiple pregnancies by reducing multiple ovarian follicular development and by a more aggressive cancellation policy, or conversion to IVF.169 De Geyter and coworkers used ultrasound-guided aspiration of supernumerary follicles as a way of avoiding multiple-gestation pregnancies without canceling cycles.178 A study by Pasqualotto179 found that the total number of follicles was not predictive of the occurrence of multiple gestation. However, another study demonstrated a relationship between multiple gestation and the number of follicles of 15 mm or more.180 A safe alternative to ovarian follicular aspiration or cancellation may be to convert an IUI cycle to IVF, thereby giving clinicians control over how many embryos are introduced into the uterus. Conversion also prevents the complete financial loss and frustration of a canceled cycle by maintaining a pathway toward possible pregnancy, although the
added costs of IVF are incurred.181 In conclusion, none of the methods suggested to reduce the risk of multiple pregnancies after ovarian stimulation and IUI proved to be effective without reducing the success rate significantly or adding significant cost by conversion to IVF. An ovulation induction agent that would achieve ovarian monofollicular development in most cycles with comparable success rate to ovarian stimulation with FSH would be an exciting approach for ameliorating the burden of multiple pregnancies after ovarian stimulation with IUI.
Ovarian Hyperstimulation Syndrome The incidence of OHSS in clomiphene citrate-treated women and in association with mild gonadotropin stimulation for IUI is difficult to determine, because definitions of the syndrome vary widely among studies. Mild OHSS (moderate ovarian enlargement) is relatively common but does not require active management. When clomiphene citrate induction of ovulation proceeds in the recommended incremental fashion designed to establish the minimum effective dosage, the risk of severe OHSS (massive ovarian enlargement, progressive weight gain, severe abdominal pain, nausea and vomiting, hypovolemia, ascites, and oliguria) is remote.23 This complication is discussed in more detail in Chapter 40.
Ovarian Cancer There is an uncertain association between ovarian cancer and clomiphene citrate treatment, derived from two epidemiologic studies published early in the past decade. The first was a casecontrol study concluding that ovarian cancer risk was increased nearly threefold overall in women receiving various infertility treatments, including clomiphene citrate.182 The study methodology was widely criticized for several reasons, the most important being that it compared infertile treated women to fertile women rather than to infertile untreated women, even though infertility and nulliparity have long been recognized as risk factors for ovarian cancer. There was no apparent increase in ovarian cancer risk in treated women who conceived. The second study was a cohort study concluding that risk of ovarian tumors was increased in women treated with clomiphene citrate.183 Comparisons within the clomiphene citrate-treated cohort showed no increase in risk with less than 12 cycles of treatment. This study too was widely criticized, primarily because it included cancers of varying types and tumors of low malignant potential (e.g., epithelial, germ cell, stromal); the pathophysiology of each is likely very different. The results of subsequent studies have been reassuring, but the question of whether treatment with ovulation-inducing drugs increases risk of ovarian tumors or cancer remains unsettled and cannot be summarily dismissed.184–187 Certainly, no causal relationship between ovulation-inducing drugs and ovarian cancer has been established. Patients with concerns should be counseled that an increase in risk is possible but not established. In addition, carrying a pregnancy to term and using oral contraceptives for 2 or more years have both been demonstrated to significantly reduce overall ovarian cancer risk188–190 and could offset any potential increase in risk from fertility therapy. No change in prescribing practices is warranted, but prolonged treatment with clomiphene citrate is generally futile and should, therefore, be avoided, primarily because it offers little hope of success.23
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Chapter 37 Induction of Ovulation
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Chemically, clomiphene citrate is a nonsteroidal triphenylethylene derivative and is chemically related to diethylstilbestrol and tamoxifen. Clomiphene citrate acts mainly as an antiestrogen. Clomiphene citrate binds estrogen receptors for an extended period of time, weeks rather than hours as is the case with natural estrogen. The antiestrogenic effect on the hypothalamus, and possibly the pituitary, is believed to be the main mechanism of action of clomiphene citrate for ovarian stimulation. It is believed that the hypothalamus is the main site of action because in normally ovulatory women, clomiphene citrate treatment was found to increase GnRH pulse frequency. During clomiphene citrate treatment, levels of both LH and FSH rise, then fall after the typical 5-day course of therapy is completed. Treatment typically begins with a single 50-mg tablet daily for 5 consecutive days, increasing by 50-mg increments in subsequent cycles until ovulation is induced. Usually the LH surge is observed from 5 to 12 days after the last clomiphene citrate tablet. Clomiphene citrate treatment has been reported to successfully induce ovulation in 60% to 80% of properly selected candidates. Clomiphene citrate treatment is associated with an increased risk of pregnancy loss, although this might be related to coexisting causes of infertility.
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Preliminary studies suggest that aromatase inhibitors may be an effective and safe alternative to clomiphene citrate for induction or augmentation of ovulation. The two main reasons for clomiphene ovulation failure are insulin resistance (women with PCOS) and inappropriate indication for clomiphene citrate. It is believed that most of the endocrine and reproductive benefits observed during treatment with insulin sensitizers in PCOS women are due to improving insulin resistance. Several studies demonstrated that treatment with the insulinsensitizing agent metformin alone could restore menses and cyclic ovulation in many amenorrheic PCOS women. Metformin is effective for ovulation; metformin plus clomiphene citrate appears to be very effective for achievement of pregnancy compared to clomiphene citrate alone. Aromatase catalyzes the rate-limiting step in the production of estrogens, the conversion of androstenedione and testosterone via three hydroxylation steps to estrone and estradiol, respectively. Aromatase inhibitors are completely absorbed after oral administration, with a mean terminal half-life of approximately 45 hours (range, 30 to 60 hours) with clearance from the systemic circulation mainly by the liver. Aromatase inhibitors have no adverse effects on estrogen target tissues because no estrogen receptor down-regulation occurs, in contrast to the estrogen receptor depletion observed in clomiphene citrate-treated cycles. A major advantage of an aromatase inhibitor used alone is the ability to achieve restoration of monofollicular ovulation in anovulatory infertility.
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44. Ben-Ami M, Geslevich Y, Matilsky M, et al: Exogenous estrogen therapy concurrent with clomiphene citrate: Lack of effect on serum sex hormones and endometrial thickness. Gynecol Obstet Invest 37:180–182, 1994. 45. Gonen Y, Casper RF: Sonographic determination of an adverse effect of clomiphene citrate on endometrial growth. Hum Reprod 5:670–674, 1990. 46. Nelson LM, Hershlag A, Kurl RS, et al: Clomiphene citrate directly impairs endometrial receptivity in the mouse. Fertil Steril 53:727–731, 1990. 47. Li TC, Warren MA, Murphy C, et al: A prospective, randomised, cross-over study comparing the effects of clomiphene citrate and cyclofenil on endometrial morphology in the luteal phase of normal fertile women. BJOG 99:1008–1013, 1992. 48. Hammond M, Halme J, Talbert L: Factors affecting the pregnancy rate in clomiphene citrate induction of ovulation. Obstet Gynecol 62:196–202, 1983. 49. Fritz MA, Holmes RT, Keenan EJ: Effect of clomiphene citrate treatment on endometrial estrogen and progesterone receptor induction in women. Am J Obstet Gynecol 165:177–185, 1991. 50. Yeko TR, Nicosia SM, Maroulis GB, et al: Histology of midluteal corpus luteum and endometrium from clomiphene citrate-induced cycles. Fertil Steril 57:28–32, 1992. 51. Sereepapong W, Triratanachat S, Sampatanukul P, et al: Effects of clomiphene citrate on the endometrium of regularly cycling women. Fertil Steril 73:287–229, 2000. 52. Oktay K, Berkowitz P, Berkus M, et al: The re-incarnation of an old question: Clomid effect on oocyte and embryo? Fertil Steril 74:422–423, 2000. 53. Branigan EF, Estes MA: Minimal stimulation IVF using clomiphene citrate and oral contraceptive pill pretreatment for LH suppression. Fertil Steril 733:587–590, 2000. 54. Zayed F: Outcome of stimulated in vitro fertilisation (SIVF) using clomiphene citrate and human menopausal gonadotropin in different infertility groups. Clin Exp Obstet Gynecol 263/264:227–279, 1999. 55. Schmidt GE, Kim MH, Mansour R, et al: The effects of enclomiphene and zuclomiphene citrates on mouse embryos fertilized in vitro and in vivo. Am J Obstet Gynecol 1544:727–736, 1986. 56. Yoshimura Y, Hosoi Y, Atlas SJ, Wallach EE: Effect of clomiphene citrate on in vitro ovulated ova. Fertil Steril 456:800–804, 1986. 57. Shimoya K, Tomiyama K, Hashimoto K, et al: Endometrial development was improved by transdermal estradiol in patients treated with clomiphene citrate. Gynecol Obstet Invest 474:251–254, 1999. 58. Gerli S, Gholami H, Manna A, et al: Use of ethinyl estradiol to reverse the antiestrogenic effects of clomiphene citrate in patients undergoing intrauterine insemination: A comparative, randomized study. Fertil Steril 73:1:85–89, 2000. 59. Bateman BG, Nunley WC Jr, Kolp LA: Exogenous estrogen therapy for treatment of clomiphene citrate-induced cervical mucus abnormalities: Is it effective? Fertil Steril 54:577–579, 1990. 60. Wu CH, Winkel CA: The effect of therapy initiation day on clomiphene citrate therapy. Fertil Steril 52:564–568, 1989. 61. Saleh A, Biljan MM, Tan SSSL, Tulandi T: Effects of tamoxifen (Tx) on endometrial thickness and pregnancy rates in women undergoing superovulation with clomiphene citrate (CC) and intrauterine insemination (IUI). Fertil Steril 74(Suppl1):S90, 2000. (Abstract.) 62. Unfer V, Casini ML, Costabile L, et al: High dose of phytoestrogens can reverse the antiestrogenic effects of clomiphene citrate on the endometrium in patients undergoing intrauterine insemination: A randomized trial. J Soc Gynecol Invest 11:323–328, 2004. 63. Vienonen A, Miettinen S, Blauer M, et al: Expression of nuclear receptors and cofactors in human endometrium and myometrium. J Soc Gynecol Invest 112:104–112, 2004. 64. Franks S, Adams J, Mason H, Polson D: Ovulatory disorders in women with polycystic ovary syndrome. Clin Obstet Gynaecol 12:605–632, 1985. 65. Hull MGR: The causes of infertility and relative effectiveness of treatment. In Templeton AA, Drife JO (eds). Infertility. London, Springer-Verlag, 1992, pp 33–62.
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108. Fatemi HM, Kolibianakis E, Tournaye H, et al: Clomiphene citrate versus letrozole for ovarian stimulation: A pilot study. Reprod Biomed Online 75:543–546, 2003. 109. Healey S, Tan SL, Tulandi T, Biljan MM: Effects of letrozole on superovulation with gonadotropins in women undergoing intrauterine insemination. Fertil Steril 806:1325–1329, 2003. 110. Mitwally MF, Casper RF: Aromatase inhibitors in ovulation induction. Semin Reprod Med 2:61–78, 2004. 111. Kamat A, Hinshelwood MM, Murry BA, Mendelson CR: Mechanisms in tissue-specific regulation of estrogen biosynthesis in humans. Trends Endocrinol Metab 133:122–128, 2002. 112. Naftolin F, MacLusky NJ: Aromatization hypothesis revisited. In M Serio (ed). Differentiation: Basic and Clinical Aspects. New York, Raven Press, 1984, pp 79–91. 113. Naftolin F, MacLusky NJ, Leranth CZ, et al: The cellular effects of estrogens on neuroendocrine tissues. J Steroid Biochem 30:195–207, 1988. 114. Naftolin F: Brain aromatization of androgens. J Reprod Med 39:257–261, 1994. 115. Sioufi A, Gauducheau N, Pineau V, et al: Absolute bioavailability of letrozole in healthy post-menopausal women. Biopharm Drug Dispos 18:779–789, 1997. 116. Sioufi A, Sandrenan N, Godbillon J, et al: Comparative bioavailability of letrozole under fed and fasting conditions in 12 healthy subjects after a 25 mg single oral administration. Biopharm Drug Dispos 186:489–497, 1997. 117. DePaolo LV: Inhibins, activins, and follistatins: The saga continues. Proc Soc Exp Biol Med 214:328–339, 1997. 118. Nett TM, Turzillo AM, Baratta M, Rispoli LA: Pituitary effects of steroid hormones on secretion of follicle-stimulating hormone and luteinizing hormone. Domest Anim Endocrinol 23:33–42, 2002. 119. Welt C, Sidis Y, Keutmann H, Schneyer A: Activins, inhibins, and follistatins: From endocrinology to signaling. A paradigm for the new millennium. Biol Med (Maywood) 2279:724–752, 2002. 120. McNeilly AS, Crawford JL, Taragnat C, et al: The differential secretion of FSH and LH: Regulation through genes, feedback and packaging. Reprod Suppl 61:463–476, 2003. 121. Roberts V, Meunier H, Vaughan J, et al: Production and regulation of inhibin subunits in pituitary gonadotropes. Endocrinology 124:552–554, 1989. 122. Mason AJ, Berkemeier LM, Schmelzer CH, Schwall RH: Activin B: Precursor sequences, genomic structure and in vitro activities. Mol Endocrinol 3:1352–1358, 1989. 123. Mather JP, Roberts PE, Krummen LA: Follistatin modulates activin activity in a cell- and tissue-specific manner. Endocrinology 132:2732–2734, 1993. 124. Baratta M, West LA, Turzillo AM, Nett TM: Activin modulates differential effects of estradiol on synthesis and secretion of folliclestimulating hormone in ovine pituitary cells. Biol Reprod 64:714–719, 2001. 125. Shupnik MA, Rosenzweig BA: Identification of an estrogen-responsive element in the rat LH β gene. DNA–estrogen receptor interactions and functional analysis. J Biol Chem 66:17084–17091, 1991. 126. DiGregorio GB, Nett TM: Estradiol and progesterone influence the synthesis of gonadotropins in the absence of GnRH in the ewe. Biol Reprod 35:166–172, 1995. 127. Roberts VJ, Barth S, El-Roeiy A, Yen SSC: Expression of inhibin/ activin system messenger ribonucleic acids and proteins in ovarian follicles from women with polycystic ovarian syndrome. J Clin Endocrinol Metab 79:1434–1439, 1994. 128. Yamoto M, Minami S, Nakano R: Immunohistochemical localization of inhibin subunits in polycystic ovary. J Clin Endocrinol Metab 77:859–862, 1993. 129. Anderson RA, Groome NP, Baird DT: Inhibin A and inhibin B in women with polycystic ovarian syndrome during treatment with FSH to induce mono-ovulation. Clin Endocrinol Oxf 48:577–584, 1998. 130. Lockwood GM, Muttukrishna S, Groome NP, et al: Mid-follicular phase pulses of inhibin B are absent in polycystic ovarian syndrome and are initiated by successful laparoscopic ovarian diathermy: A
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possible mechanism regulating emergence of the dominant follicle. J Clin Endocrinol Metab 83:1730–1735, 1998. Weil SJ, Vendola K, Zhou J, et al: Androgen receptor gene expression in the primate ovary: Cellular localization, regulation, and functional correlations. J Clin Endocrinol Metab 837:2479–2485, 1998. Weil S, Vendola K, Zhou J, Bondy CA: Androgen and follicle-stimulating hormone interactions in primate ovarian follicle development. J Clin Endocrinol Metab 848:2951–2956, 1999. Vendola KA, Zhou J, Adesanya OO, et al: Androgens stimulate early stages of follicular growth in the primate ovary. J Clin Invest 10112:2622–2629, 1998. Vendola K, Zhou J, Wang J, et al: Androgens promote oocyte insulinlike growth factor I expression and initiation of follicle development in the primate ovary. Biol Reprod 612:353–357, 1999. Adashi E: Intraovarian regulation: The proposed role of insulin-like growth factors. Ann NY Acad Sci 687:10–12, 1993. Giudice LC: Insulin-like growth factors and ovarian follicular development. Endocr Rev 13:641–669, 1992. Yen SSC, Laughlin GA, Morales AJ: Interface between extra-and intraovarian factors in polycystic ovary syndrome (PCOS). Ann NY Acad Sci 687:98–111, 1993. Agarwal SK, Judd HL, Magoffin DA: A mechanism for the suppression of estrogen production in polycystic ovary syndrome. J Clin Endocrinol Metab 8110:3686–3691, 1996. Jakimiuk AJ, Weitsman SR, Brzechffa PR, Magoffin DA: Aromatase mRNA expression in individual follicles from polycystic ovaries. Mol Hum Reprod 41:1–8, 1998. Nirmala PB, Thampan RV: Ubiquitination of the rat uterine estrogen receptor: Dependence on estradiol. Biochem Biophys Res Commun 2131:24–31, 1995. Rosenfeld CR, Roy T, Cox BE: Mechanisms modulating estrogeninduced uterine vasodilation. Vascul Pharmacol 382:115–125, 2002. Krasnopolskaya K, Kaluina A: Application of aromatase inhibitors Anastrosol in IVF program for the treatment of infertility associated with severe endometriosis. In Program and abstracts of the 18th Annual Meeting of the European Society for Human Reproduction and Embryology (ESHRE). Vienna, 2002, 17:75, P-438. Tredway DR, Buraglio M, Hemsey G, Denton G: A phase I study of the pharmacokinetics, pharmacodynamics, and safety of single- and multiple-dose anastrozole in healthy, premenopausal female volunteers. Fertil Steril 82:1587–1593, 2004. Ligibel JA, Winer EP: Clinical differences among the aromatase inhibitors. Clin Cancer Res 91(Pt 2):473S–479S, 2003. Hu Y, Cortvrindt R, Smitz J: Effects of aromatase inhibition on in vitro follicle and oocyte development analyzed by early preantral mouse follicle culture. Mol Reprod Dev 614:549–559, 2002. Guo Y, Guo KJ, Huang L, et al: Effect of estrogen deprivation on follicle/oocyte maturation and embryo development in mice. Chin Med J Engl 1174:498–502, 2004. Mitwally MFM, Casper RF: Single dose administration of an aromatase inhibitor for ovarian response. Fertil Steril 83:229–231, 2005. Letrozole (Femara) package insert. Novartis, East Hanover, N.J., July 1997. Anastrozole (Arimidex) package insert. Astra-Zeneca, Wilmington, Del., September 2005. Mitwally MFM, Casper RF: Pregnancy outcome after the use of an aromatase inhibitor for ovarian stimulation. Am J Obstet Gynecol 192:381–386. Bulun SE, Zeitoun KM, Takayama K, Sasano H: Estrogen biosynthesis in endometriosis: Molecular basis and clinical relevance. J Mol Endocrinol 1:35–42, 2000. Vignali M, Infantino M, Matrone R, et al: Endometriosis: Novel etiopathogenetic concepts and clinical perspectives. Fertil Steril 78:665–678, 2002. Hamilton A, Piccart M: The third-generation nonsteroidal aromatase inhibitors: A review of their clinical benefits in the second-line hormonal treatment of advanced breast cancer. Ann Oncol 10:377–384, 1999. Goss PE: Risks versus benefits in the clinical application of aromatase inhibitors. Endocr Relat Cancer 6:325–332, 1999.
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Chapter 37 Induction of Ovulation 155. Palter SF, Tavares AB, Hourvitz A, et al: Are estrogens of import to primate/human ovarian folliculogenesis? Endocr Rev 223:389–424, 2001. 156. Yanase T, Simpson ER, Waterman M: 17-hydroxylase/17,20-lyase deficiency: From clinical investigation to molecular definition. Endocr Rev 12:91–108, 1991. 157. Rabinovici J, Blankstein J, Goldman B, et al: IVF and primary embryonic cleavage are possible in 17-hydroxylase deficiency despite extremely low intrafollicular 17β E2. J Clin Encrinol Metab 68:693–697, 1989. 158. Schoot DCJM, Herjan JT, Bennink C, et al: Human recombinant FSH induced growth of preovulatory follicles without concomitant increase in androgen and estrogen biosynthesis in a woman with isolated GT deficiency. J Clin Endocrinol Metab 74:1471–1473, 1992. 159. Shoham Z, Mannaerts B, Insler V, Coelingh HB: Induction of follicular growth using recombinant human follicle-stimulating hormone in two volunteer women with hypogonadotropic hypogonadism. Fertil Steril 59:738–742, 1993. 160. Shoham Z, Balen A, Patel A, Jacobs HS: Results of ovulation induction using human menopausal gonadotropins or purified follicle-stimulating hormone in hypogonadotropic hypogonadism patients. Fertil Steril 56:1048–1053, 1991. 161. Dawood MY: In vitro fertilization, gamete intrafallopian transfer and superovulation with intra-uterine insemination: Efficacy and potential health hazards on babies delivered. Am J Obstet Gynecol 174:1208–1217, 1996. 162. Births: Final data for 2001. Natl Vital Stat Rep Volume 51, 2003. 163. Collins MS, Bleyl JA: Seventy-one quadruplet pregnancies: Management and outcome. Am J Obstet Gynecol 162:1384–1392, 1990. 164. Kaufman E, Malone FD, Harvey-Wilkes KB, et al: Neonatal morbidity and mortality associated with triplet pregnancy. Obstet Gynecol 91:342–348, 1998. 165. Botting BJ, Davies IM, Macfarlane AJ: Recent trends in the incidence of multiple births and associated mortality. Arch Dis Child 62:941–950, 1987. 166. Lipitz S, Frenkel Y, Watts C, et al: High-order multifetal gestation— management and outcome. Obstet Gynecol 76:215–218, 1990. 167. Callahan L, Hall JE, Ettner SL, et al: The economic impact of multiplegestation pregnancies and the contribution of assisted-reproduction techniques to their incidence. NEJM 331:244–249, 1994. 168. Thurin A, Hausken J, Hillensjo T, et al: Elective single-embryo transfer versus double-embryo transfer in in vitro fertilization. NEJM 351:2392–2402, 2004. 169. Adashi EY, Barri PN, Berkowitz R, et al: Infertility therapy-associated multiple pregnancies births: An ongoing epidemic. Reprod Biomed Online 75:515–542, 2003. 170. Martin KA, Hall JE, Adams JM, Crowley WF Jr: Comparison of exogenous gonadotropins and pulsatile gonadotropin-releasing hormone for induction of ovulation in hypogonadotropic amenorrhea. J Clin Endocrinol Metab 77:125–129, 1993. 171. Schenker JG, Jarkoni S, Granat M: Multiple pregnancies following induction of ovulation. Fertil Steril 35:105–123, 1981.
172. Jain T, Missmer SA, Hornstein MD: Trends in embryo-transfer practice and in outcomes of the use of assisted reproductive technology in the United States. NEJM 35016:1639–1645, 2004. 173. Wapner RJ, Davis GH, Johnson A, et al: Selective reduction of multifetal pregnancies. Lancet 335:90–93, 1990. 174. Berkowitz RL, Lynch L, Lapinski R, Bergh P: First-trimester transabdominal multifetal pregnancy reduction: A report of two hundred completed cases. Am J Obstet Gynecol 169:17–21, 1993. 175. Gilstrap LC III, Brown CE: Prevention and treatment of preterm labor in twins. Clin Perinatol 15:71–77, 1988. 176. Lipitz S, Reichman B, Paret G, et al: The improving outcome of triplet pregnancies. Am J Obstet Gynecol 161:1279–1284, 1989. 177. Corson SL, Dickey RP, Gocial B, et al: Outcome in 242 in vitro fertilization–embryo replacement or gamete intrafallopian transferinduced pregnancies. Fertil Steril 51:644–650, 1989. 178. De Geyter C, De Geyter M, Nieschlag E: Low multiple pregnancy rates and reduced frequency of cancellation after ovulation induction with gonadotropins, if eventual supernumerary follicles are aspirated to prevent polyovulation. J Assist Reprod Genet 15:111–116, 1998. 179. Pasqualotto E, Falcone T, Goldberg J, et al: Risk factors for multiple gestation in women undergoing intrauterine insemination with ovarian stimulation. Fertil Steril 72:613–618, 1999. 180. Richmond JR. Deshpande N, Lyall H, et al: Follicular diameters in conception cycles with and without multiple pregnancy after stimulated ovulation induction. Hum Reprod 20:756–760, 2005. 181. Antman AM, Politch JA, Ginsburg ES: Conversion of high-response gonadotropin intrauterine insemination cycles to in vitro fertilization results in excellent ongoing pregnancy rates. Fertil Steril 77:715–720, 2002. 182. Whittemore AS, Harris R, Itnyre J, et al: Characteristics relating to ovarian risk: Collaborative analysis of 12 US case-control studies. Am J Epidemiol 136:1184–1203, 1992. 183. Rossing MA, Daling JR, Weiss NS, et al: Ovarian tumors in a cohort of infertile women. NEJM 331:771–776, 1994. 184. Venn A, Watson L, Lumley J, et al: Breast and ovarian cancer incidence after infertility and in vitro fertilization. Lancet 346:995–1000, 1995. 185. Modan B, Ron E, Lerner-Geva L, et al: Cancer incidence in a cohort of infertile women. Am J Epidemiol 147:1038–1042, 1998. 186. Mosgaard BJ, Lidegaard O, Kjaer SK, et al: Infertility, fertility drugs, and invasive ovarian cancer: A case-control study. Fertil Steril 67:1005–1012, 1997. 187. Potashnik G, Lerner-Geva L, Genkin L, et al: Fertility drugs and the risk of breast and ovarian cancers: Results of a long-term follow-up study. Fertil Steril 71:853–859, 1999. 188. Pike MC, Pearce CL, Wu AH: Prevention of cancers of the breast, endometrium and ovary. Oncogene 23:6379–6391, 2004. 189. Khoo SK: Cancer risks and the contraceptive pill. What is the evidence after nearly 25 years of use? Med J Aust 17:185–190, 1986. 190. Fathalla MF: Factors in the causation and incidence of ovarian cancer. Obstet Gynecol Surv 2711:751–768, 1972.
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Section 6 Infertility and Recurrent Pregnancy Loss Chapter
38
Assisted Reproductive Technology: Clinical Aspects Michael P. Steinkampf and Beth A. Malizia
INTRODUCTION In vitro fertilization (IVF) is a remarkable scientific approach to the common clinical problem of infertility. The initial development of IVF in humans can be attributed directly to a team of two investigators, Drs. Patrick Steptoe and Robert Edwards. It was in 1969 that Dr. Edwards first announced, “Human oocytes have been matured and fertilized by spermatozoa in vitro. There may be certain clinical and scientific uses for human eggs fertilized by this procedure.”1 This understated conclusion marked the first successful attempt to fertilize human eggs in a laboratory. Currently, more than 100,000 cycles of human IVF and similar techniques are performed each year in the United States, resulting in the birth of more than 40,000 babies. IVF, together with the much less commonly used techniques of gamete intrafallopian transfer (GIFT) and zygote intrafallopian transfer (ZIFT), are collectively referred to as assisted reproductive technologies (ART). Today, ART procedures are responsible for approximately 1% of all children born in the United States annually.2
Assisted Reproductive Technology Techniques ART can be defined as fertility treatment that involves removing eggs from a woman’s ovaries and combining them with sperm in a laboratory. Methods used to achieve this result include IVF, GIFT, and ZIFT. In Vitro Fertilization
The concept of IVF as a treatment for infertility is straightforward: obtain eggs from the ovaries, mix them with sperm in a dish containing culture medium, and transfer the eggs back to the woman after fertilization has occurred. However, this technique took more than 100 years to develop. In 1891, the first successful transfer of an embryo from one animal to another that resulted in birth was reported, using rabbits of two different strains. However, these embryos were obtained from eggs fertilized in vivo. Further progress toward the goal of IVF was slowed because of limited understanding of the maturation of eggs and sperm required to achieve fertilization and embryo development. In 1959, successful IVF was reported using rabbits.3 The first human birth to result from IVF was achieved in England in 1978.4 John and Lesley Brown had 9 years of infertility secondary to bilateral fallopian tube obstruction. Dr. Patrick Steptoe surgically retrieved a single mature oocyte from one of Lesley’s ovaries during a natural cycle. Dr. Robert G. Edwards combined John’s sperm with the oocyte in the laboratory and
the resulting embryo was placed into Lesley’s uterus a few days later. On July 25, 1978, Louise Joy Brown was delivered by cesarean section at approximately 37 weeks’ gestation, and weighed 5 pounds 12 ounces. Although this first human IVF birth employed a surgical procedure to retrieve the oocyte produced in a natural menstrual cycle, most IVF today is performed after ovarian stimulation so that multiple eggs can be retrieved transvaginally with a sonographically guided needle. Currently more than 99% of ART procedures in the United States employ IVF and transcervical embryo transfer.
Gamete Intrafallopian Transfer GIFT utilizes the same ovarian stimulation and egg retrieval as IVF, but the eggs and sperm are transferred to the fallopian tubes immediately after egg retrieval, forgoing the need for IVF and culture medium. GIFT was developed with the rationale that the fallopian tube was an environment superior to a culture dish for fertilization and early embryo development. Although early reports of GIFT indicated higher success rates than with IVF, improvements in the formulation of culture media and other laboratory techniques have resulted in equivalent success rates for GIFT and IVF.5,6 A disadvantage of GIFT is that it can only be performed in patients with normal fallopian tubes. Another disadvantage of GIFT compared to IVF is that it generally requires laparoscopy, with all the risks and expenses associated with this outpatient surgery. Currently, GIFT procedures account for less than 0.2% of ART treatments in the United States.
Zygote Intrafallopian Transfer ZIFT is a hybrid between IVF and GIFT. For ZIFT, oocytes are retrieved using a transvaginal needle, fertilized in vitro, and cultured overnight. Zygote-stage embryos are then laparoscopically transferred to the fallopian tubes approximately 24 hours after oocyte retrieval. ZIFT offers the advantages of IVF with the direct observation of the success of the IVF process. Injection of sperm into the egg can be performed if necessary. It allows the subsequent transfer of the embryos to the fallopian tube for optimal development. Although some studies comparing ZIFT to conventional IVF have found ZIFT to be superior, other studies have shown little difference.7,8 This uncertainty and the need for two surgical procedures for ZIFT (i.e., transvaginal egg retrieval and laparoscopic embryo transfer) have limited the popularity of this technique. However, ZIFT has found a place in the treatment of
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Section 6 Infertility and Recurrent Pregnancy Loss infertile women with congenital or acquired cervical abnormalities and in patients who fail to achieve pregnancy after repeated IVF cycles.9,10 Currently, ZIFT procedures account for approximately 0.5% of ART treatments in the United States.
INDICATIONS FOR ASSISTED REPRODUCTION Tubal Factor Infertility Tubal Adhesions
Tubal adhesions account for 30% to 40% of cases of female infertility. Tubal damage or adnexal adhesion typically arise from salpingitis, appendicitis, endometriosis, or previous pelvic surgery. Laparoscopic surgery to remove adhesions and open tubes can yield pregnancy rates of more than 50% in women with relatively mild disease.11 In women with severe tubal damage or extensive dense adhesions, surgery is unlikely to result in pregnancy. IVF is indicated in these patients and in women who have failed to conceive after infertility surgery. Hydrosalpinges
Tubal surgery is also indicated in women with hydrosalpinges who are contemplating IVF. Hydrosalpinges are associated with decreased pregnancy and live birth rates after IVF.12 Although the pathophysiology of this relationship is not completely understood, bilateral salpingectomy improves the success of subsequent IVF, especially in women with bilateral hydrosalpinges. Tubal Ligation
Up to 25% of women who have undergone bilateral tubal sterilization will come to regret their decision and wish to have more children. Risk factors for tubal ligation regret include young age at time of sterilization, relationship with a new partner, loss of a child, and having been sterilized immediately postpartum or postabortion. Up to 5% will seek tubal anastomosis, which is a highly effective treatment option in properly selected patients.13 Success rates depend on the site of the anastomosis, the length of residual tube, the age of the patient, and the presence of other infertility causes. In vitro fertilization is an effective alternative to surgery for women who have undergone a tubal ligation. This is particularly true for women without adequate residual tubal length, those who are poor surgical candidates, and those who would prefer to avoid surgery. IVF is also an option in women who have undergone tubal anastomosis, but who do not achieve pregnancy within 12 months. The choice between IVF and tubal surgery is usually made based on relative success rates and the cost to the patients. If either IVF or surgery are covered completely or in part by insurance, the covered choice will usually see greater utilization.
Endometriosis
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Endometriosis is a common cause of both infertility and pain (see Chapter 49). The effects of endometriosis on fertility can be decreased but not completely circumvented by the combination of gonadotropin stimulation and intrauterine insemination.14 The decrease in monthly fecundibility roughly correlates with the
severity of disease, although there is a poor correlation between endometriosis stage and the chance of pregnancy after surgical treatment.15 In vitro fertilization is an effective treatment for infertile women with endometriosis who fail to conceive with less aggressive treatment. Some, but not all, studies suggest that endometriosis affects IVF success. Endometriosis has been implicated in poor ovarian reserve, poor quality of oocytes and embryos, and poor implantation.16–21 Prolonged hormonal suppression using gonadotropin-releasing hormone (GnRH) analogues appears to improve IVF success in women with endometriosis.22
Male Factor Infertility At least 40% of men who are members of infertile couples have abnormal semen analyses.23 Achieving pregnancy via conventional IVF in oligospermic men met with disappointing results largely due to fertilization failure.24 The treatment of male infertility dramatically improved with the development of intracytoplasmic sperm injection (ICSI).25 Injection of a single sperm into the egg appears to solve fertilization failure for the majority of male infertility problems. Currently, ICSI is used in about half of all ART treatment cycles. This technique is discussed in more detail in Chapter 39. Antisperm Antibodies
Antisperm antibodies are a relatively uncommon and difficult to treat cause of infertility. IVF with ICSI has been found to be an effective treatment for women with antisperm antibodies, even in patients with a higher density of such antibodies.26 In one study, patients with antisperm antibodies had a 32% clinical pregnancy rate after IVF with ICSI.27 Because antisperm antibodies are relatively uncommon, it does not appear that routine screening for antisperm antibodies before IVF is cost-effective.28
Unexplained Infertility Up to 30% of infertile couples will have unexplained infertility.29 Treatment options for unexplained infertility include ovarian stimulation with clomiphene citrate or gonadotropins, plus intrauterine insemination. IVF is an effective treatment for couples with unexplained infertility who fail to conceive with these approaches. The success of IVF in couples with unexplained infertility appears to be comparable to that achieved in cases of tubal damage or endometriosis.24
Failure to Conceive After Ovulation Induction Anovulatory women who fail to conceive with ovulation induction are good candidates for IVF. Unfortunately, the pregnancy rates after IVF are lower and the complication rates higher for patients with polycystic ovary syndrome (PCOS). In one study of 110 women with PCOS who underwent IVF/ICSI, women with a body mass index (BMI) greater than 29 kg/m2 had a lower pregnancy rate per oocyte retrieval and a higher occurrence of ovarian hyperstimulation syndrome as compared to PCOS patients with a BMI of 29 kg/m2 or lower.30 Treatment with metformin to lower insulin levels in patients with PCOS undergoing IVF has been reported to improve success rates.31
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Chapter 38 Assisted Reproductive Technology: Clinical Aspects Diethylstilbestrol Exposure
Evaluation of the Ovaries
Women exposed in utero to diethylstilbestrol (DES) are known to have an increased risk of infertility.32 These women are also at increased risk of pregnancy complications as a result of reproductive tract abnormalities such as a T-shaped or hypoplastic cavity, a septate uterus, or uterine synechiae.33 IVF outcomes in DES-exposed women are comparable with respect to ovarian response and embryo quality, but delivery rates are lower, possibly due to uterine abnormalities.33
Determining the capacity of the ovaries to respond to ovarian stimulation is an important part of determining patient suitability for assisted reproduction. Age of the patient remains the most powerful predictor of ovarian response. However, a variety of hormonal and sonographic indices of ovarian reserve are also available.
In theory, only three things are needed to accomplish a successful IVF cycle: eggs, sperm, and a uterus into which the embryos are transferred. Although fertility testing is covered in Chapter 34 and 35, certain aspects of the evaluation specific to ART treatment follow.
Evaluation of the Uterus Assessment of the uterine cavity is accomplished by transvaginal ultrasonography, hysteroscopy, or hysterosalpingography. Sensitivity of transvaginal ultrasonography to detect uterine abnormalities can be improved by instillation of fluid into the uterine cavity. Many programs perform transvaginal ultrasonography on all patients just before the start of an IVF cycle to ensure that no uterine abnormalities have recently developed. Endometrial Polyps
Endometrial polyps, benign localized overgrowths of endometrial tissue of uncertain etiology, are present in up to 10% of asymptomatic premenopausal women over age 30.34 It is assumed that endometrial polyps decrease fertility. For this reason, all large polyps are removed prior to IVF. For smaller polyps that first appear during ovarian stimulation for IVF, optimal management remains to be determined. The problem is that removal requires interruption of the cycle and delay of IVF. A series of 49 women with endometrial polyps less than 2 cm in diameter who underwent IVF without removing the polyp found pregnancy and miscarriage rates were comparable to the general pregnancy rate of their IVF clinic population, although there was a trend toward a higher miscarriage rate.35 At the present time, the decision to continue despite the polyp or stop the cycle and remove the polyp must be made on a caseby-case basis. Hydrosalpinges
The presence of hydrosalpinges is well documented to decrease the success rate for IVF.36 Whether pregnancy rates can be improved by salpingectomy remains less certain. A recent metaanalysis of three randomized, controlled trials indicated that the chance of live birth with IVF was doubled by pretreatment salpingectomy.12 This effect seems to be most apparent in women with bilateral hydrosalpinges and with hydrosalpinges that are sonographically visible.37 Drainage of hydrosalpinges at the time of egg retrieval can be performed, but it is uncertain if this improves IVF pregnancy rates. At present, many IVF programs offer patients with a sonographically visible hydrosalpinx the option of pretreatment salpingectomy.
It has long been known that reproductive capacity declines with increasing age.38 The age-dependent decline in female fertility can be partly attributed to the fact that women have a finite and nonreplenishable number of germ cells. The peak number of germ cells occurs at midgestation during fetal life and declines continuously thereafter, with an accelerated loss of oocytes between ages 37 and 38.39 Diminished ovarian reserve is a term used to indicate decline in reproductive capacity associated with ovarian follicular depletion and diminished oocyte quality. The success of IVF declines with age in a similar fashion (Fig. 38-1). For women undergoing IVF, diminished ovarian reserve is associated with poor ovarian response to gonadotropins, cycle cancellation, and lower chances of conception. Despite the known correlation with chronologic age and ovarian reserve, there exists a tremendous amount of variability in patients. As a result, multiple markers of ovarian reserve have been sought to supplement age as a predictor of ovarian response to stimulation in IVF. Timely recognition of reduced ovarian reserve is important for counseling patients prior to IVF. Basal FSH
Measurement of serum follicle-stimulating hormone (FSH) in the early follicular phase of the menstrual cycle (day 3) is widely employed to assess the potential responsiveness of the ovaries to stimulation and can predict to some degree subsequent IVF pregnancy rates. This measurement of “basal” FSH is relatively inexpensive and easily obtained. However, the ideal way to use basal FSH levels for counseling prior to IVF remains controversial.
50 Live Birth Rate (%)
PATIENT SELECTION—PREDICTORS OF SUCCESS FOR IVF
Age
40 30 20 10 0 23
25
27
29 31 33 35 37 39 Patient Age (years)
41
43
45
Figure 38-1 Live birth rates per cycle start by age of the woman, for cycles performed in the United States in the year 2003 (From Centers for Disease Control and Prevention: 2003 Assisted Reproductive Technology Success Rates. Available at http://www.cdc.gov/reproductivehealth/ART/ index.htm. Accessed 17 September 2005.
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Section 6 Infertility and Recurrent Pregnancy Loss A direct correlation of the basal FSH and IVF outcome measurements was found in a study of 441 patients undergoing 758 consecutive IVF cycles.40 Patients with basal FSH levels greater than 25 mIU/mL had only a 3.6% ongoing pregnancy rate, whereas those with basal FSH levels less than 15 mIU/mL had a 17% pregnancy rate. They also noted that fewer follicles were aspirated, fewer oocytes were obtained, and fewer embryos were available for transfer in the high FSH group compared to the low FSH group. A recent meta-analysis of 21 studies indicated that basal FSH levels were moderately predictive for poor response but poorly predictive for pregnancy. In women over age 40, neither the basal nor the stimulated (clomiphene citrate challenge test [CCCT]) FSH level were able to predict pregnancy rates with IVF. However, no patient with a basal FSH level greater than 11.1 mIU/mL or a CCCT FSH greater than 13.5 mIU/mL (i.e., day 10 serum FSH) carried a pregnancy past 20 weeks. Many IVF programs use a cut-off value for the basal FSH to determine when to cancel an IVF cycle. A study of 230 consecutive IVF cycles using GnRH antagonists found that the 97.5th percentile predictive value of basal FSH resulting in pregnancy was 10 mIU/mL. Patients should be counseled that these data suggest that pregnancy with IVF is unlikely in patients with basal FSH levels above this cutoff. However, it is important to note that FSH has a wide fluctuation both between cycles in the same patients as well as between particular hormonal assays. It is therefore critical for each program to evaluate its own normative data for this assay as well as consider repetition of borderline hormonal values in patients.
higher cycle cancellation rate, and a lower clinical pregnancy rate than women whose inhibin B concentration was at least 45 pg/mL.44 However, another study of 120 women undergoing IVF found that inhibin B levels did not improve the prediction of IVF success over using patient age and basal FSH level.
Day 3 Estradiol
Clomiphene Citrate Challenge Test
Serum estradiol levels on day 3 of the menstrual cycle have also been found to be predictive of subsequent IVF pregnancy rates. One study found that the ongoing pregnancy rates for patients with day 3 estradiol levels less than 30 pg/mL were significantly higher than for patients with estradiol levels between 31 and 75 pg/mL.41 No pregnancies occurred in patients with day 3 estradiol levels greater than 75 pg/mL. Another study found that the 97.5th percentile predictive value for day 3 estradiol for pregnancy was 56 pg/mL. Basal elevations of estradiol are an independent marker of poor ovarian response to stimulation even in cycles without a rise in FSH. This is presumably because high circulating levels of serum estradiol suppress FSH levels. This hypothesis was confirmed in a study of 225 patients, where no pregnancies occurred after IVF with day 3 estradiol greater than 100 pg/mL, despite FSH levels less than 15 mIU/mL in all patients.42 In a study of 2476 IVF patients who had normal day 3 FSH levels, patients with day 3 estradiol levels either less than 20 pg/mL or greater than 80 pg/mL had an increased cancellation rate.43 However, estradiol levels are no longer predictive of IVF pregnancy rates once the patients had more than three maturing follicles.
The CCCT decribed by Navot and colleagues is a method to dynamically elucidate the ovarian response.48 The test is performed by measuring basal FSH on day 3 (day 2 is acceptable), administering clomiphene citrate (100 mg, days 5 to 9), and then remeasuring a FSH on day 10 (days 9 and 11 are also acceptable). An abnormal test was originally defined as an FSH level after clomiphene citrate more than 2 standard deviations from the basal level. Many clinicians define an abnormal CCCT as an FSH value greater than 12 mIU/mL on either cycle day 3 or 10. The CCCT has been shown to have a sensitivity of 43% and a specificity of 76%, using IVF cycle cancellation as an endpoint in a study of 198 women.49 Positive and negative predictive values were 37% and 80%, respectively. The estradiol levels during ovarian stimulation, the number of retrieved oocytes, and the rate of transfer cycles were significantly lower in patients with an abnormal CCCT. Forty-three percent of the abnormal test results were abnormal only on their elevation of day 10 or 11 FSH and not on their basal FSH level. However, the rate of pregnancies per started cycle did not show a statistically significant difference, which was attributed to the low numbers of patients. A recent meta-analysis of a total of 1352 patients from 12 studies on basal FSH and 7 studies on CCCT found that basal FSH had a sensitivity of 6.6% and a specificity of 99.6% for identifying inability to achieve pregnancy in an IVF cycle, whereas CCCT sensitivity was 25.9% and specificity was 98.1%.50 This study suggests that basal FSH and CCCT are similar in the ability to predict a clinical pregnancy and that, although a normal test is not helpful, an abnormal test is highly predictive that pregnancy will not occur with IVF. Based on this, the authors
Inhibin B
570
Elevation of FSH occurs in part as a result of diminished inhibin secretion by developing follicles. It follows that inhibin levels may also predict IVF success. Inhibin is a heterodimer that is secreted in two forms: inhibin A and inhibin B. In one IVF study, women with a day 3 serum inhibin B concentration less than 45 pg/mL had lower estradiol levels, fewer oocytes retrieved, a
Antimüllerian Hormone
Antimüllerian hormone is produced by developing granulosa cells. A recent study of 130 women undergoing their first IVF cycle found that low antimüullerian hormone levels were associated with fewer eggs retrieved and increased chance of cycle cancellation.45 According to another study, basal serum antimüllerian hormone level may be a better predictor of IVF outcome than FSH, estradiol, or inhibin levels.46 Antral Follicle Count
The number of small follicles visible by transvaginal ultrasonography early in the follicular phase is another means used to predict ovarian response in IVF. A prospective IVF study of 130 women younger than age 45 indicated that the number of antral follicles on cycle day 3 provided better prognostic information regarding poor ovarian response during hormone stimulation for IVF than age or basal FSH, estradiol, or inhibin B levels. Another IVF study of 120 women also found that a single antral follicle count was predictive of poor ovarian response, although the predictive accuracy could be increased by repeating the count on a subsequent cycle and using the higher of the two counts.47 The exact number of antral follicles that predicts outcome is still uncertain.
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Chapter 38 Assisted Reproductive Technology: Clinical Aspects recommended that basal FSH be used rather than CCCT because of its simplicity and lower cost. Combining Screening Markers
It is apparent that there are clear limitations to each of the proposed markers for ovarian response to stimulation. Therefore, attempts have been made to combine some of these markers to improve the predictive ability compared to a single marker alone. When basal FSH and estradiol are combined for patients undergoing IVF cycles, one study reported no pregnancies in patients with basal FSH levels greater than 17 mIU/mL and basal estradiol level greater than 45 pg/mL.41 Another study of 74 IVF patients with basal FSH levels less than 15 mIU/mL examined the ratio of basal FSH to LH.51 This study found that an elevated FSH-to-LH ratio greater than 3.6 correlated with a lower day 8 estradiol, lower peak estradiol, and fewer follicles greater than 15 mm in size A randomized study of 110 patients evaluated multiple markers for ovarian reserve, including the exogenous FSH ovarian reserve test. This test involves the administration of 300 IU of rFSH (Gonal-F) on cycle day 3 with serum measurements of FSH, estradiol, and inhibin B before and 24 hours after administration. They concluded that the exogenous FSH ovarian reserve test was better than the CCCT at predicting the number of large follicles resulting from controlled ovarian hyperstimulation.52 Conclusion
At present, basal FSH screening remains the screening tool of choice in many IVF centers in the United States. Issues examining different assay standards, variation by laboratory, and cycle-tocycle variability of any biomarker of ovarian reserve will have to be addressed. Perhaps the most important aspect of ovarian reserve testing is the way in which this information is used to counsel the infertile couple. None of these tests have absolute sensitivity or specificity; however, the counseling of patients with abnormal tests to consider other options of treatment such as oocyte donation or adoption remains reasonable. Moreover, none of the data presented here indicates the ability of a single or even multiple tests to accurately exclude patients from treatment. The ultimate decision about the treatment course planned should be an individualized process between the infertile woman or couple and the physician.
OVARIAN STIMULATION FOR IVF As noted above, the first successful human IVF cycle utilized a natural menstrual cycle. However, subsequent investigators found that much higher pregnancy rates could be achieved if ovarian stimulation was utilized. Monitoring the response to ovarian stimulation is accomplished with a combination of transvaginal ultrasonography and serum estradiol levels. Some programs also monitor serum progesterone and LH levels, although the utility of this additional monitoring is believed to be limited in modern stimulation protocols.
Clomiphene Citrate Wood and colleagues were the first to report that administration of clomiphene citrate followed by human chorionic gonadotropin
(hCG) to complete oocyte maturation both increased IVF success rates and improved scheduling efficiency for egg retrieval.53 Clomiphene citrate was commonly used by early IVF programs in the United States until higher success rates were reported using human menopausal gonadotropins. Clomiphene citrate is used at an oral dose of 50 to 150 mg/day for 5 days beginning on day 2 or 3 of the menstrual cycle, and hCG (5,000 to 10,000 units intramuscular) is given when the lead follicle reaches 18 mm in diameter. Although gonadotropins remain the standard ovarian stimulants for IVF, the convenience and low cost of clomiphene has caused it to be reconsidered as an option for good-prognosis IVF patients.54–56
Gonadotropins The use of the injectable gonadotropin FSH, with or without LH, circumvents the natural decline of FSH that occurs with development of the dominant follicle. In effect this rescues oocytes that would be physiologically lost to atresia in a natural cycle, which selects only one dominant follicle. Initial reports in the United States using human menopausal gonadotropins (a combination of FSH and LH) for IVF were considered spectacular, with pregnancies achieved in 5 of 24 laparoscopic egg retrievals (21%), at a time when IVF pregnancy rates after other stimulation protocols were less than 10%.57 Although initial success likely was due in part to improvements in laboratory techniques and patient selection, gonadotropin injections soon became the standard treatment to prepare women for egg retrieval. Human chorionic gonadotropin 5,000 to 10,000 units is typically used to mimic the LH surge and complete oocyte maturation in gonadotropin cycles. Egg retrieval is performed 34 to 36 hours after the hCG injection. Urinary and recombinant hCG products appear to give equivalent results.58 Early preparations of human menopausal gonadotropins contained roughly equal amounts of FSH and LH. These preparations were extracted from the urine of postmenopausal women and also contained substantial amounts of urinary albumin and globulins. More recently, recombinant FSH and LH has become commercially available. There has been much investigation and discussion of the relative merits of different gonadotropin preparations.59,60 Most programs in the United States have gravitated to some combination of FSH and LH for ovarian stimulation, along with a GnRH analogue. Recombinant and urinary FSH products seem to give equivalent pregnancy rates.61 Adjunctive stimulation with clomiphene in gonadotropin cycles, while lowering total gonadotropin doses required, has fallen out of favor because of the risk of spontaneous ovulation.
Gonadotropin-Releasing Hormone Agonists In the early years of IVF, more than one quarter of stimulation cycles did not reach the stage of egg retrieval, primarily due to a premature LH surge.62 Long-term administration of GnRH agonists initially stimulates LH and FSH release, referred to as a flare or agonist phase. This is followed within 2 weeks by suppression of gonadotropin levels. This effect has been exploited for more than 20 years in IVF cycles.63 Initially this drug was reserved for patients who demonstrated a premature LH surge, but its popularity surged when high pregnancy rates were documented with routine use.64
571
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Section 6 Infertility and Recurrent Pregnancy Loss In the United States, the most popular GnRH agonist is leuprolide acetate, given subcutaneously at doses of 0.25–1.0 mg/day. The routine use of GnRH agonists improves IVF success by reducing the rate of cycle cancellation, but the chance of pregnancy per embryo transfer is also increased, probably because more eggs are obtained, hence giving a larger selection of embryos for transfer.65 Long Protocol
GnRH agonists are typically administered in a “long” protocol, whereby the flare and down-regulation occur before gonadotropins are begun. The agonist is typically started in the midluteal phase, or just after menses in anovulatory women. Pituitary downregulation is confirmed after the onset of menstrual bleeding by a serum estradiol level 1 to 2 weeks after initiation of the drug, and gonadotropins are begun thereafter. Some programs simply use the appearance of a menstrual bleed as a sign that estradiol levels are suppressed. Many programs prescribe a birth control pill for 1 or 2 months before starting the GnRH agonists. This helps schedule a series of patients and may facilitate pituitary down-regulation and prevention of ovarian cysts that may develop on the agonist. Flare Protocol
Alternatively, the agonist can be given in the early follicular phase along with or just before initiation of gonadotropins. Use of a GnRH agonist flare protocol reduces the gonadotropin dose required to achieve follicular development, and this feature is particularly appealing for patients who have a poor response to gonadotropins. However, pregnancy rates in poor responders using the long and short GnRH agonist protocols seem to be equivalent.66 One study found that routine use of the GnRH agonist flare protocol resulted in lower pregnancy rates compared to the long protocol, possibly because stimulation of LH during the follicular phase may impair normal oocyte maturation.67
Gonadotropin-Releasing Hormone Antagonists
572
Antagonists of GnRH have recently become commercially available for clinical use. Earlier antagonists were associated with severe histamine release with local and systemic side effects. Histamine release does not seem to be a problem with the newer antagonists, ganirelix and cetrorelix. The advantage of these drugs is the absence of a gonadotropin flare when the drugs are started in the follicular phase. A recent multicenter IVF trial compared the GnRH antagonist ganirelix acetate with a long protocol using a GnRH agonist, leuprolide.68 In this study, GnRH analogue administration was required for only 4 days on average using the GnRH antagonist compared to 19 days with the GnRH agonist. However, fewer eggs were obtained in the GnRH antagonist group. The dose of GnRH antagonist administered affects IVF success. Excessive or insufficient suppression of LH and progesterone levels with GnRH antagonist decreases clinical pregnancy rates.69 In poor-responder IVF patients, a protocol using GnRH antagonist is associated with lower pregnancy rates than the GnRH agonist flare protocol.70 In a meta-analysis of five randomized, controlled IVF trials of GnRH antagonist versus GnRH agonist protocols, antagonist protocols were associated with a lower clinical pregnancy rate.71 It is possible that the lack
of experience with the antagonists may explain this difference. Given the potential advantages of GnRH antagonists over agonists for IVF, protocols using these drugs will continue to be investigated.
Natural-Cycle IVF IVF only became clinically useful after the development of methods to obtain mature eggs that could be reliably fertilized in vitro. Nevertheless, the complications and expense of ovarian stimulation are often treatment barriers for many women, especially for those with poor or exaggerated responses and those desiring egg retrieval to preserve fertility before cancer treatment. Although IVF programs have periodically reassessed the feasibility of natural-cycle IVF, the vast majority of IVF cycles continue to be performed in stimulated cycles because of higher efficiency and success rates.72–74 Recently, the possibility of harvesting multiple immature eggs in a spontaneous menstrual cycle has been proposed to overcome some of the limitations of natural-cycle IVF.
In Vitro Maturation Mammalian oocytes are maintained in meiotic arrest throughout most of follicular development; the resumption of meiosis I is induced by the preovulatory LH surge, which is emulated during an IVF cycle by intramuscular administration of hCG. Although the precise mechanisms that regulate the control of oocyte maturation remain obscure, it has been recognized for more than 70 years that immature oocytes liberated from antral follicles undergo spontaneous maturation in culture, termed in vitro maturation, without the need for hormonal stimulation.75 Unfortunately, oocytes matured in vitro have a reduced ability to produce embryos that result in live offspring. Immature oocytes are typically obtained in the mid- to late follicular phase of the menstrual cycle. Administration of hCG 36 hours before egg collection appears to facilitate oocyte maturation.76 Because oocytes that have undergone in vitro maturation have a decreased IVF rate, ICSI is routinely performed on these oocytes. If embryos are transferred back to the patient in the same cycle, endometrial preparation with estradiol and progesterone is required. To date, in vitro maturation has been most successfully employed in young women with multiple antral follicles, who typically have a high chance of pregnancy with conventional IVF. Despite this selection bias, IVF pregnancy rates are substantially lower than in stimulated cycles.77 However, in cancer patients, where the time and hormonal milieu associated with the traditional IVF cycle may adversely affect the patient’s survival, there may be some advantage to the in vitro maturation technique. Likewise, patients with PCOS who undergo ovarian hyperstimulation with ovulation induction agents may be candidates for in vitro maturation.
MONITORING OVARIAN STIMULATION The goal of ovarian stimulation for IVF is to stimulate the development of multiple follicles containing mature oocytes. Improved timing for hCG administration and subsequent oocyte retrieval has been an important factor in the improvement of IVF pregnancy rates. Initially, timing for IVF was determined by
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Chapter 38 Assisted Reproductive Technology: Clinical Aspects measuring estradiol levels in urine or serum. Unfortunately, estradiol monitoring alone cannot distinguish between the development of a single preovulatory follicle or multiple immature follicles. Fortunately, follicle size does correlate with oocyte maturity. When ultrasonography, first abdominally and then vaginally, was used to monitor ovulation induction, IVF pregnancy rates improved. By the time IVF became widely available clinically, the use of vaginal sonography as an adjunct to gonadotropin stimulation was well established.
Ultrasonographic Monitoring In spontaneous cycles, maximal preovulatory follicle diameter is typically 20 to 24 mm. However, early work with gonadotropin ovulation induction for IVF suggested that pregnancy could be achieved if hCG was given when the lead follicle was as small as 14 mm. Initially, there was much confusion as to the optimal follicle size for hCG administration in IVF cycles, in part because of differences in equipment sensitivity and measurement techniques. Early published recommendations for hCG timing ranged from 12 mm to 20 mm diameter for the lead follicle. Many centers today administer hCG when at least two follicles have achieved a mean diameter of 18 mm. In IVF cycles with high estradiol levels (greater than 3000 pg/mL), 16 mm diameter for the lead follicle is used as the criteria for hCG administration to limit the risk of ovarian hyperstimulation. In patients with a low response to gonadotropins, a 20 mm diameter for the lead follicle is often used to allow the maturation of subordinate follicles without sacrificing the lead follicle to postmaturity. Cycles in which only one or two mature follicles develop are usually canceled. Follicle diameters are determined by averaging either two or three dimensions to account for the irregular follicle shape often seen in stimulated cycles as a result of crowding of multiple follicles in the ovarian cortex. Using the average of two dimensions has been shown to correlate well with the follicular volume unless the follicle shape is predominantly ellipsoid. In these cases, the average of three dimensions might be a better reflection of volume. Three-dimensional ultrasonography and power Doppler angiography can be used to monitor IVF cycles, although the clinical usefulness of these techniques is still under investigation.
Endometrial Monitoring The uterus undergoes characteristic sonographic changes during follicular development. As estradiol levels increase, the endometrium thickens, with a trilaminar pattern typically seen late in the follicular phase. Predicting the chance of pregnancy in a treatment cycle by sonographic examination of the endometrium has been an enticing goal for IVF practitioners. Endometrial Thickness
Periovulatory endometrial thickness, determined by measuring both the anterior and posterior endometrium, has been shown to be greater in IVF cycles that resulted in conception.78 Studies suggest that pregnancy after IVF appears to be most likely in patients with an endometrial thickness of 9 to 12 mm on the day of hCG administration and may be reduced with endometrial thickness greater than this. Whether a minimal endometrial thickness is required to achieve pregnancy remains uncertain. Although pregnancies are
less common when the endometrial thickness is less than 8 mm, pregnancies have been reported with an endometrial thickness as little as 4 mm. The reason for this wide range is unclear, because the mean interobserver variation of endometrial stripe measurement is only 1 mm. Endometrial Pattern
Smith and colleagues79 described several ultrasonic endometrial patterns developing during ovarian stimulation for IVF. Two periovulatory endometrial patterns can be consistently recognized by high-resolution sonography: (1) a hypoechoic pattern, usually with a trilaminar appearance, and (2) a homogeneous, hyperechoic pattern.79 Some studies have reported that the pregnancy rates of IVF patients with hyperechoic endometrium are lower than that obtained when a trilaminar or homogeneous hypoechoic pattern is observed, although other studies have failed to confirm this observation. It has been speculated that the endometrial patterns seen by ultrasound are a reflection of changes in uterine blood flow. In a color flow Doppler study of 96 IVF cycles, 24% of women with hyperechoic endometrium had no subendometrial blood flow, compared to only 4% of women with a trilaminar endometrial pattern.80 In this study, none of eight patients with undetectable endometrial blood flow conceived. In a study of subendometrial blood flow index just prior to ovarian stimulation for IVF, Doppler sonography of the spiral or uterine arteries did not predict subsequent IVF cycle outcome.81 Treatment of Abnormal Endometrial Vascularity
If poor endometrial development is somehow related to IVF failure, can something be done to improve uterine vascularity? In a small study of oocyte donor recipients who had failed to develop an endometrial thickness of at least 8 mm in a previous evaluation cycle, patients were randomly assigned to receive low-dose aspirin (81 mg/day) or no treatment. Aspirin treatment did not increase endometrial thickness. However, women whose endometrial thickness in the final treatment cycle was 8 mm or more were much more likely to conceive if they had received aspirin. Aspirin has been proposed as an adjunct to ovarian stimulation for IVF, with one report of improved ovarian and uterine blood flow and increased pregnancy rates with its administration during gonadotropin treatment.82 However, two large trials failed to confirm any of these beneficial effects.83,84 It has been hypothesized that uterine artery blood flow could be increased by the administration of sildenafil (Viagra), a type 5-specific phosphodiesterase inhibitor that relaxes vascular smooth muscle. Although a small IVF series suggested that the chances of pregnancy could be dramatically increased by administration of vaginal sildenafil before and during ovarian stimulation, a subsequent randomized, controlled trial failed to show any effect of sildenafil on endometrial thickness or uterine blood flow.85
Estradiol Monitoring Estradiol monitoring during ovarian stimulation for IVF has not been found to be useful for timing of the hCG injection, but does appear useful in adjusting the dose of gonadotropin and for predicting the risk of ovarian hyperstimulation. Part of the art of IVF is knowing when to adjust gonadotropin levels up or down
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Section 6 Infertility and Recurrent Pregnancy Loss
Figure 38-2 Transvaginal probe set for oocyte retrieval. The probe is covered with a sterile glove and stockinette. Specific probe sheaths are also commercially available.
or cancel cycles based on number of follicles and estradiol levels. Although exact guidelines vary widely from center to center, many patients will cancel an IVF cycle if the estradiol levels do not reach 300 pg/mL by day 8 of stimulation. After this point, the dose of gonadotropin is usually not changed if the estradiol levels rise between 50% and 100% every 48 hours. The risk of severe hyperstimulation increases if the estradiol levels are greater than 3800 pg/mL at the time of hCG injection in women with polycystic ovaries or greater than 2400 pg/mL for women with hypothalamic amenorrhea.
OOCYTE RETRIEVAL Retrieval Techniques
574
Retrieval of oocytes is generally performed 34 to 36 hours after administration of hCG to allow adequate oocyte maturation and avoid ovulation. As noted above, laparoscopy was initially used for oocyte retrieval. This technique required that the ovaries could be visualized laparoscopically, and some IVF programs would perform a “screening” laparoscopy some time before the IVF cycle to confirm ovarian accessibility. Subsequently, ultrasound-guided retrieval techniques were developed, which allowed retrieval of oocytes without the need for general anesthesia or direct visualization of the ovaries. Although transabdominal or periurethral oocyte retrievals have been performed in the past, the transvaginal egg retrieval has come to be the standard technique for egg retrieval in virtually all IVF programs. Transvaginal egg retrieval employs a needle guide mounted atop a high-frequency endovaginal ultrasound probe (Fig. 38-2). The room setup for a typical IVF oocyte retrieval procedure is quite minimal (Fig. 38-3). The patient is placed in the dorsal lithotomy position, and the perineum and vagina are irrigated with sterile saline solution. Some programs precede this with an antiseptic cleanser, although IVF outcomes may be compromised by antiseptic contamination.86 A broad-spectrum antibiotic is frequently given IV or by mouth before the egg retrieval; for example, oral doxycycline 100 mg daily for four days starting on
Figure 38-3 Procedure room for transvaginal egg retrieval. A footactuated vacuum pump is used to obtain the follicle aspirates, and a warming table keeps the follicle aspirates warm during the procedure.
the day of the retrieval. Pelvic infections are uncommon, but patients with endometriomas may be at higher risk despite the use of perioperative antibiotics.87
Anesthesia A variety of anesthetic techniques have been reported for transvaginal egg retrievals, including local, epidural, spinal, or general anesthetics, but many programs use IV sedation/analgesia.88 Typically, a short-acting analgesic such as fentanyl is used in conjunction with a benzodiazepine or propofol.89 Supplemental oxygen may be administered by mask or nasal cannula as needed. No clear relationship has been confirmed between IVF outcome and the choice of anesthestic technique for transvaginal egg retrieval, although general anesthesia has been reported to decrease IVF pregnancy rates.88
EMBRYO TRANSFER The critical part between oocyte retrieval and embryo transfer occurs in an embryology laboratory (see Chapter 39). The patient is called the day after the retrieval and told how many oocytes fertilized (Fig. 38-4). Embryos may be transferred into the uterus anytime during preimplantation development. The first successful IVF pregnancy occurred after transfer of a single blastocyst, but clinicians unable to duplicate this success turned to the transfer of embryos on day 2 or 3 after retrieval to overcome the limitations of their culture systems. At present, most IVF programs in the United States transfer embryos on day 3 after oocyte retrieval, but embryo transfers done on day 2 appear to give comparable results2,90 (Fig. 38-5). Pregnancy can occur when the fertilized egg is transferred to the uterus 1 day after fertilization. With the increasing availability of high-quality commercially produced IVF culture media, the transfer of one or two embryos on day 5 or 6 after fertilization (at the blastocyst stage) has been proposed as a way of minimizing the risk of high-order multiple pregnancy while maintaining satisfactory pregnancy rates. Blastocyst transfer has several potential advantages: (1) delaying
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Figure 38-4 Fertilized egg obtained via in vitro fertilization. The round structures within the cytoplasm are the pronuclei.
Figure 38-5 Two embryos on day 3 of development. The cell membranes are becoming indistinct as compaction occurs. These embryos were transferred and resulted in a singleton pregnancy.
the embryo transfer to day 5 or 6 after fertilization allows for more detailed examination of embryo morphology (Fig. 38-6); (2) the embryonic genome is activated after about 2 days of development, and prolonged culture facilitates selection of the most robust embryos; (3) preimplantation embryos do not reach the uterine cavity until day 4 or 5 in vivo.91 The uterus provides a different nutritional milieu from the oviduct, and it has been postulated that the transfer of day 2 or 3 embryos to the uterine cavity may reduce their potential for implantation.92 However, prolonged culture of embryos may decrease their capacity to develop and implant. Depending on embryo quality and culture conditions, in some IVF cycles few or no embryos may reach the blastocyst stage, resulting in few or no embryos
Figure 38-6 Expanded blastocyst on day 5 of development. The inner cell mass (which ultimately develops into the fetus) is apparent.
to transfer or cryopreserve.93 A recent meta-analysis of 16 randomized, controlled trials of day 2 or 3 versus day 5 or 6 embryo transfer found no significant differences in the rates of pregnancy, birth, multiple gestation, or high-order multiple gestation94 (Table 38-1). Rates of embryo freezing per couple were significantly higher in day 2 or 3 transfers, and patients randomized to day 5 or 6 transfer were three times more likely to have no embryos to transfer. The results were similar in studies in which only patients with a favorable prognosis were enrolled. In studies where cumulative pregnancy rates for both fresh and frozen embryos were specified, pregnancies were more likely to occur in the day 2 or 3 group. Balancing the risks and benefits of multiple-embryo transfer remains one of the most vexing problems of ART. The transfer of more than one embryo increases the chance of pregnancy but also increases the risk of multiple gestations. The Society for Assisted Reproductive Technology recommends that no more than two embryos be transferred to women under age 35 who have a favorable prognosis for pregnancy.95 A recent randomized, controlled trial of elective single-embryo versus double-embryo transfer suggested that comparable pregnancy rates could be achieved and multiple pregnancies avoided in young women with good embryo quality if embryo cryopreservation was routinely used for the second embryo.96
Embryo Transfer Technique Embryo transfers are performed in the dorsal lithotomy position. A speculum is inserted into the vagina, and the cervix is cleansed with culture medium or sterile saline solution. A trial transfer using an empty catheter is performed if not previously done, and the embryos are then transferred in a small volume (5 to 20 μL) of culture medium. A variety of embryo transfer catheter types are available, including rigid or soft, side- or end-loading, with or without an introducer. The chance of pregnancy with
575
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Section 6 Infertility and Recurrent Pregnancy Loss Table 38-1 Meta-analysis Results of Cleavage Stage Versus Blastocyst Transfer: Effect on Clinical Pregnancy Rates (Blake 2005)94 Day 5/6 n/N
Day 2/3 n/N
Bungum et al 2003106
32/61
36/57
Coskun et al 2000107
39/100
39/101
Devreker et al 2000108
4/11
1/12
Emiliani et al 2003109
39/82
46/89
Frattarelli et al 2003110
18/29
10/28
Gardner et al 1998a111
32/45
31/47
Hreinsson et al 2004112
22/64
25/80
Karaki et al 2002112
28/80
24/82
Kolibianakis et al 2004114
75/226
75/234
Levitas et al 2004115
5/23
4/31
Levron et al 2002116
8/46
20/44
Motta et al 1998 A % B117
21/58
21/58
Rienzi et al 2002118
29/50
27/48
Schillaci et al 2002119
24/60
23/60
Van der Auwera et al 2002120
29/70
20/66
Total (95% Cl)
1005
1037
Odds Ratio (Fixed) 95% CI
Weight (%)
䊏 䊏 䊏 䊏 䊏 䊏 䊏 䊏
䊏
Odds Ratio (Fixed) 95% CI
7.8
0.64 [0.31, 1.34]
10.4
1.02 [0.58, 1.79]
0.3
6.29 [0.58, 68.42]
10.2
0.85 [0.47, 1.55]
1.7
2.95 [1.00, 8.65]
3.9
1.27 [0.53, 3.07]
6.4
1.15 [0.57, 2.32]
6.8
1.30 [0.67, 2.52]
21.7
1.05 [0.71, 1.56]
1.2
1.88 [0.44, 7.94]
7.4
0.25 [0.10, 0.66]
5.9
1.00 [0.47, 2.13]
䊏
5.1
1.07 [0.48, 2.39]
䊏
6.1
1.07 [0.52, 2.23]
5.3
1.63 [0.80, 3.30]
100.0
1.05 [0.88, 1.26]
䊏 䊏 䊏
䊏
♦
Study
Total events: 405 (Day 5/6), 402 (Day 2/3) Test for heterogeneity chi-square=18.99 df=14 p=0.17 I??=26.3% Test for overall effect z=0.57 p=0.6 0.1 0.2 0.5 Favours day 2/3
IVF is maximized if embryos are accurately and atraumatically placed within the uterus. Ultrasound guidance for embryo transfer was first reported by Strickler and colleagues in 1985.97 Since then, a number of retrospective studies have shown favorable effects on pregnancy rates when ultrasound was used to facilitate placement of the transfer in the uterine cavity. Recently, a randomized, controlled trial of ultrasound-assisted embryo transfer found that 50% of patients conceived in the ultrasound-guidance group, compared with only 34% of controls.98 The beneficial effect of ultrasound guidance for embryo transfer may be due in part to the bladder filling required to perform the examination, which in itself has been shown to have a salutary effect on embryo transfer; however, transvaginal sonography guidance (without a full bladder) has also been shown to improve the success of embryo transfer. Although sonographically guided embryo transfer is still not done in all IVF programs, it may be particularly useful when the practice transfer is difficult, especially in cases in which soft catheters lacking tactile feedback are used.
LUTEAL PHASE MANAGEMENT
576
The ability to achieve pregnancy in ART cycles is impaired unless hormone supplementation is administered. Aspiration of granulosa cells during oocyte retrieval impairs corpus luteum function, as does the use of GnRH agonists, which limit the secretion of LH in the luteal phase. The result can be an iatrogenic luteal phase defect.99 Luteal phase support with hCG or progesterone after IVF results in an increased pregnancy rate. The use of hCG has not
1
2 5 10 Favours day 5/6
been shown to be better than intramuscular progesterone, but is associated with a greater risk of ovarian hyperstimulation syndrome. Progesterone can be given orally, intravaginally, or intramuscularly. The optimal route of progesterone administration has not yet been established, but pregnancy rates may be higher with intramuscular administration.100 Many IVF programs still administer intramuscular progesterone in oil 50 mg/day, beginning on the day of the egg retrieval. In patients who conceive, progesterone supplementation continues until a fetal heartbeat is seen on ultrasound. This might not be necessary based on a randomized, controlled trial of more than 300 IVF cycles that did not show a difference in the rate of successful pregnancies between women who continued progesterone in early pregnancy compared with those who stopped treatment after the first positive pregnancy test.101
SUCCESS OF ASSISTED REPRODUCTIVE PROCEDURES Many endpoints have been used to measure IVF success rates. Outcomes of interest include a positive pregnancy test, a sonographically visible pregnancy, appearance of fetal cardiac activity, and birth of a viable infant. Most patients are interested in the “take home baby rate” (i.e., the chance of a obtaining a healthy infant that they can bring home from the hospital after delivery). However, this statistic takes time to accumulate and is reflective of a fertility clinic’s success in years past. Choosing the denominator for calculating success rates is also problematic. Most commonly, all initiated cycles are included. However, statistics are sometimes calculated using only cycles that have progressed to retrieval or those that have resulted in
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Chapter 38 Assisted Reproductive Technology: Clinical Aspects embryo transfer. The most meaningful calculations are made using the total number of initiated cycles, but using only cycles in which oocytes are retrieveds or embryos are transferred is more likely to reflect the quality of the IVF laboratory. Less than 30% of all “fresh” IVF cycles (i.e., cycles using the patient’s own nonfrozen embryos) result in a live birth. If a woman does not conceive in her first IVF attempt but has a normal response to ovarian stimulation, her chance of subsequent IVF success decreases by 2% to 5% in each subsequent cycle.2,102,103 The success rates for IVF are highly dependent on the age of the woman, with birth rates declining from about 40% per initiated cycle in women younger than age 23 to about 15% at age 40.2 This decline in success is almost entirely due to increasing age of the eggs, because IVF success using donor oocytes is independent of the recipient’s age. About 30% of ART births are twins, and 3% are triplets or higher-order multiples. The incidence of high-order multiple births from IVF has declined significantly over the past decade.2 The success of alternative ART procedures, such as GIFT or ZIFT, is about the same as for IVF, but these procedures currently account for less than 5% of ART cycles in the United States.
OVUM DONATION Donor oocyte programs are available in most IVF centers in the United States and abroad. Patients may wish to find their own donor in a sister, another relative, or a friend. However, most egg donor IVF cycles employ an anonymous donor.
often include endometrial biopsies to demonstrate a histologic response to exogenous hormones.104 Many regimens for endometrial preparation have been described, and successful pregnancies have also been reported in embryo transfer of donor oocytes in natural cycles. If the recipient has no baseline ovarian function, no down-regulation is required. If the recipient has endogenous ovarian function, GnRH agonist treatment is begun on day 21 in the luteal phase of the previous cycle. Once down-regulation occurs, the recipient is placed on estradiol with monitoring of serum estradiol levels every 3 to 7 days to maintain serum estradiol levels of 150 to 300 pg/mL. Progesterone supplementation (typically 50 mg/day IM) is begun on the day after embryo transfer. In a mock cycle an endometrial biopsy may be obtained 10 to 12 days after the progesterone is started. In a therapeutic cycle the embryo transfer is performed on day 4 of progesterone treatment.
Success Rates The use of donor oocytes for IVF consistently results in high pregnancy rates when young healthy fertile women donated their oocytes, with pregnancy rates from 51% to 58% per IVF cycle.105 The pregnancy rates did not differ significantly according to the number of previous donated cycles or the interval between donation cycles. Many ethical issues surround donor oocyte programs. Controversies exist on directed donor oocyte programs, financial compensation for oocyte donation, and the methods used to recruit donors. These issues warrant further clarification by the clinicians involved in donor oocyte programs.
The Donor Some programs may have donor matching as a part of their ART treatment; others may rely on an outside company to supply this service to its patients. Either way the donors are screened for medical, reproductive, and psychological fitness. These donors are stringently assessed, including screening for transmittable infectious or genetic diseases. Semen donors have the advantage of their sperm being cryopreserved while the screening process is undertaken, but the current low efficiency of oocyte cryopreservation mandates that fresh eggs are used. The donors must undergo controlled ovarian hyperstimulation with its associated complications and must be meticulously informed and educated about the treatment involved in oocyte donation. Many programs also advise legal counsel for those patients requesting directed donors secondary to the potential for litigious issues to arise after treatment. Regimens for donor treatment follow those outlined for controlled ovarian hyperstimulation with gonadotropins. The donors are requested to abstain from intercourse during the stimulation cycle to decrease the risk of multiple gestation and ectopic pregnancy.
The Recipient The recipient’s uterus must be primed and the endometrium prepared to receive the fertilized embryos, which requires significant coordination. Most centers will take their recipients through a “mock” cycle before the donor cycle to ensure that adequate endometrial thickness can be achieved. These cycles
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ART procedures are responsible for about 1% of all children born in the United States annually. Hydrosalpinges are associated with decreased pregnancy and live birth rates after IVF. Conventional IVF in oligospermic men is associated with poor results largely due to fertilization failure. The pregnancy rates after IVF are lower and the complication rates are higher for patients with polycystic ovary syndrome. Pre-IVF screening includes assessment of the uterine cavity and tubes to exclude intrauterine and tubal pathology that may impact success. Uterine polyps of greater than 2 cm and ultrasound-visualized hydrosalpinx should be removed before IVF. Methods to assess ovarian reserve include a day 3 serum FSH, the clomiphene citrate challenge test, a day 3 serum inhibin or estradiol, antimüllerian hormone, and antral follicle counts. Most programs in the United States have gravitated to some combination of FSH and LH for ovarian stimulation, along with a GnRH analogue. GnRH agonists are typically administered in a long protocol, whereby the flare and down-regulation occur before gonadotropins are begun. Follicle growth is monitored by transvaginal ultrasonography. Many centers administer hCG when at least two follicles have achieved a mean diameter of 18 mm.
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Endometrial pattern and thickness are monitored throughout the stimulation cycle. A trilaminar pattern and a thickness of 9 to 12 mm seems to be the ideal response. Oocyte retrieval is performed under ultrasound guidance under conscious sedation. Embryos are usually transferred on day 3 (cleaved embryo) or 5 (blastocyst) after oocyte retrieval under ultrasound guidance.
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Luteal phase support with hCG or progesterone after IVF results in an increased pregnancy rate. hCG is associated with a higher risk of ovarian hyperstimulation syndrome.
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1. Edwards RG, Bavister BD, Steptoe PC: Early stages of fertilization in vitro of human oocytes matured in vitro. Nature (London) 221:632–635, 1969. 2. Centers for Disease Control and Prevention: 2003 Assisted Reproductive Technology Success Rates. Available at http://www.cdc.gov/ reproductivehealth/ART/index.htm. Accessed 17 September 2005. 3. Chang MC: Fertilisation of rabbit ova in vitro. Nature (London) 179:466–467, 1952. 4. Australian Broadcasting Corporation. Interview with Roberts Edwards. The Health Report. 25 April 2005. Available at http://www.abc.net.au/ rn/talks/8.30/helthrpt/stories/s1349685.htm. Accessed on 18 September 2005. 5. Sayama M, Araki S, Motoyama M, et al: The clinical efficacy of gamete intrafallopian transfer by minilaparotomy versus in vitro fertilization and embryo transfer. J Obstet Gynaecol Res 22:409–416, 1996. 6. Pandian Z, Bhattacharya S, Nikolaou D, et al: The effectiveness of IVF in unexplained infertility: A systematic Cochrane review. Hum Reprod 18:2001–2007, 2003. 7. Van Voorhis BJ, Syrop CH, Vincent RD, et al: Tubal versus uterine transfer of cryopreserved embryos: A prospective randomized trial. Fertil Steril 63:578–583, 1995. 8. Levran D, Mashiach S, Dor J, et al: Zygote intrafallopian transfer may improve pregnancy rate in patients with repeated failure of implantation. Fertil Steril 69:26–30, 1998. 9. Fluker MR, Bebbington MW, Munro MG: Successful pregnancy following zygote intrafallopian transfer for congenital cervical hypoplasia. Obstet Gynecol 84:659–661, 1994. 10. Levran D, Farhi J, Nahum H, et al: Prospective evaluation of blastocyst stage transfer versus zygote intrafallopian tube transfer in patients with repeated implantation failure. Fertil Steril 77:971–977, 2002. 11. Valle RF: Tubal cannulation. Obstet Gynecol Clin North Am 22:519–540, 1995. 12. Johnson NP, Mak W, Sowter MC: Surgical treatment for tubal disease in women due to undergo in vitro fertilisation. Cochrane Database Syst Rev2004, CD002125.pub2. 13. Hanafi MM: Factors affecting the pregnancy rate after microsurgical reversal of tubal ligation. Fertil Steril 80:434–440, 2003. 14. Hughes EG: The effectiveness of ovulation induction and intrauterine insemination in the treatment of persistent infertility: A metaanalysis. Hum Reprod 12:1865–1872, 1997. 15. Guzick DS, Silliman NP, Adamson GD, et al: Prediction of pregnancy in infertile women based on the American Society for Reproductive Medicine’s revised classification of endometriosis. Fertil Steril 67:822–829, 1997. 16. Olivennes F, Feldberg D, Liu HC, et al: Endometriosis: A stage by stage analysis— role of in vitro fertilization. Fertil Steril 64:392–398, 1995. 17. Pellicer A, Oliveira N, Ruiz A, et al: Exploring the mechanism(s) of endometriosis related infertility: An analysis of embryo development and implantation in assisted reproduction. Hum Reprod 10:91–97, 1995. 18. Brizek CL, Schlaff S, Pellegrini VA, et al: Increased incidence of aberrant morphological phenotypes in human embryogenesis: An association with endometriosis. J Assist Reprod Genet 12:106–112, 1995. 19. Tinkanen H, Kujansuu E: In vitro fertilization in patients with ovarian endometriomas. Acta Obstet Gynecol Scand 79:119–122, 2000.
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103. Silberstein T, Trimarchi JR, Gonzalez L, et al: Pregnancy outcome in in vitro fertilization decreases to a plateau with repeated cycles. Fertil Steril 84:1043–1045, 2005. 104. Sauer MV, Paulson RJ, Moyer DL: Assessing the importance of endometrial biopsy prior to oocyte donation. J Assist Reprod Genet 14:125, 1997. 105. Opsahl MS, Blauer KL, Black SH, et al: Pregnancy rates in sequential in vitro fertilization cycles by oocyte donors. Obstet Gynecol 97:201, 2001. 106. Bungum M, Bungum L, Humaidan P, et al: Day 3 versus day 5 embryo transfer: A prospective randomized study. Reprod BioMed Online 7:98–104, April 2003. 107. Coskum S, Hollanders J, Al-Hassan S, et al: Day 5 versus day 3 embryo transfer: A controlled randomized trial. Hum Reprod 15:1947–1952, 2000. 108. Devreker F, Delbaere A, Emiliani S, et al: Prospective and randomized comparison between transfer on day 2 or day 5 for patients with more than four IVF attempts. ESHRE P135, 2000. 109. Emiliani S, Delbaere A, Vannin A, et al: Similar delivery rates in a selected group of patients, for day 2 and day 5 embryos both cultured in sequential medium: A randomized study. Hum Reprod 18:2145–2150, 2003. 110. Frattarelli JL,Leondires MP, McKeeby JL, et al: Blastocyst transfer decreases multiple pregnancy rates in vitro fertilization cycles: A randomized controlled trial. Fertil Steril 79:228–230, 2003. 111. Gardner DK, Schoolcraft WB, Wagley L, Schlenker T, Stevens J, Hesla J. A prospective randomized trial of blastocyst culture and transfer in in-vitro fertilization. Hum Reprod 13:3434–3440, 1998. 112. Hreeinsson J, Rosenlund B, Fridstrom M, et al: Embryo transfer is equally effective at cleavage stage and blastocyst stage: A randomized prospective study. Eur J Obstet Gyn Reprod Biol 117:194–200, 2004. 113. Karaki RZ, Samarraie SS, Younis NA, et al: Blastocyst culture and transfer: A step toward improved in vitro fertilization outcome. Fertil Steril 77:114–118, 2002. 114. Kolibianakis EM, Zilopoulos K, Verpoest W, et al: Should we advise patients undergoing in vitro fertilization to start a cycle leading to a day 3 or day 5 transfer? Hum Reprod 19:2550–2554, 2004. 115. Levitas E, Lunenfeld E, Har-Vardi I, et al: Blastocyst-stage embryo transfer in patients who failed to conceive in three or more day 2-3 embryo transfer cycles: A prospective, randomized study. Fertil Steril 81:567–571, 2004. 116. Levron J, Shulman A, Bider D, et al: A prospective randomized study comparing day 3 with blastocyst-stage embryo transfer. Fertil Steril 77:1300–1301, 2002. 117. Motta LA, Alegretti JR, Pico M, et al: Blastocyst vs. cleaving embryo transfer: A prospective randomized trial. Fertil Steril 70(Suppl 1):S17, 1998. 118. Rienzi I, Ubaldi F, Iacobelli M, et al: Day 3 embryo transfer with combined evaluation at the pronuclear and cleavage stages compares favourably with day 5 blastocyst transfer. Hum Reprod 17:1852–1855, 2002. 119. Schillaci R, Castelli A, Vassiliadis A, et al: Blastocyst stage versus day 2 embryo transfer in IVF cycles. Abstracts of the 18th Annual Meeting of ESHRE. Vienna, 2002, p 418. 120. Van der Auwera I, Debrock S, Spiessens C, et al: A prospective randomized study: Day 2 versus day 5 embryo transfer. Hum Reprod 17:1507–1512, 2002.
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Assisted Reproductive Technology: Laboratory Aspects Damon Davis, Cristine Silva, Melissa Hiner, and Gary D. Smith
INTRODUCTION Far-reaching advances in laboratory techniques and culture conditions have been made since 1978, when the first baby conceived by in vitro fertilization (IVF) was born in England. To date, thousands of children have been born as a result of IVF and related techniques, termed assisted reproductive technologies (ART), many of which originated in the animal sciences field. Assisted reproductive technology laboratories are considered to be high-complexity laboratories due to the level of knowledge, responsibility, and precision needed to perform the necessary procedures. The clinical andrologist/embryologist must always be aware that only meticulous attention to all details of a procedure can optimize chances of success in an IVF cycle. Within this chapter we focus on procedures that are commonly performed within an ART laboratory and that contribute to success in treating infertility.
HUMAN SEMEN: PREPARATION AND EVALUATION Assessment of semen quality is a critical first step in the evaluation of the infertile couple. The laboratory evaluation of semen quality involves the assessment of sperm fertilizing ability. However, there are many limitations of current laboratory procedures for the assessment of this sperm function. Nonetheless, an expectation of the probability of fertilization is important for the determination of the specific ART procedure required. Another important laboratory step is the preparation of sperm or sperm-containing tissue for fertilization of oocytes.
Basic Semen Evaluation Semen analysis is a critical component of the laboratory evaluation of the infertile man. Although it is the cornerstone of diagnosis, it should be noted that the semen analysis is not a stand-alone measure of fertility. In addition to the quality of the ejaculate, the presence of adequate erection and ejaculation, and the ability of the ejaculated spermatozoa to penetrate the cervical mucus, traverse the uterus and fallopian tube, and inseminate the ovum are all components that determine the fertility potential of a man. Nevertheless, an accurate semen analysis provides descriptive semen parameters upon which initial clinical diagnoses and decisions may be based.
Semen Collection Evaluation of infertility is the most common reason for basic semen analysis. Another common medical indication for this procedure is follow-up after a vasectomy to confirm sterility. Men with threatened future fertility may have their semen analyzed before storage for future insemination. Regardless of the reason for semen analysis, it is important to realize that the production and submission of a specimen of semen for analysis may be difficult, embarrassing, or distasteful for some patients. For patients undergoing infertility evaluation, there may be associated feelings of frustration, which may make the collection of a semen sample a particularly stressful or unpleasant event. For these reasons, it is vital to have experienced staff to adequately prepare the patient for semen collection. Written and oral instructions should be given well in advance of planned specimen production. The patient should be counseled to abstain from sexual activity for a period of 2 to 5 days before semen analysis. This period should remain consistent within patients to reduce intersample variation with repeated measures. Many clinicians limit male infertility evaluation to a single semen analysis if the initial sample is found to be normal. However, a thorough infertility evaluation requires analysis of two ejaculates collected as least 1 month apart because semen quality varies over time.1 If either one of the two ejaculates are abnormal, additional samples should be evaluated. Some clinicians recommend that all fertility patients undergo semen analysis once or twice yearly during the duration of their treatment. More frequent analysis may be indicated in postsurgical patients as a part of routine follow-up. Masturbation is the preferred method for the production of a complete and uncontaminated semen specimen. The glans penis should be cleaned with a wet towel, avoiding the use of soap. Oil-based lubricants should also be avoided because many are toxic to spermatozoa. In instances when the patient objects to masturbation, coitus interruptus using special condoms designed for semen collection may be utilized. Generally, coitus interruptus should be avoided because vaginal secretions may contaminate the specimen and it is difficult to ensure complete collection. Conventional latex condoms should be avoided because near-ubiquitous spermicidals quickly decrease spermatozoa viability. Other methods of sperm collection will be discussed later. It is preferable for samples to be collected near the andrology assessment area. Rooms designated for production of semen samples should be located in a quiet part of the facility and doors should be labeled with DO NOT DISTURB signs. Reading
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Section 6 Infertility and Recurrent Pregnancy Loss materials and/or video aids should be available for those men requiring them. The patient should be provided with clean, appropriately labeled, wide-mouthed containers for collection. The container should be composed of nontoxic plastic and should be sterile. Containers obtained by the patient at home may harbor residual detergents or soaps that are toxic to spermatozoa. Prompt transport of the sample to the laboratory, within 1 hour, is crucial to accurate testing. During this time, the sample should be protected from temperature extremes. Attempts should be made to keep the sample at body temperature during transit. Prolonged exposure to direct sunlight should also be avoided. All samples should be handled before, during, and after analysis using universal precautions.
Semen Parameters Semen Appearance
The semen sample is first evaluated by visual inspection at room temperature. A normal sample is homogeneous and gray-white, gray-yellow, or yellowish in appearance. If spermatozoa concentration is low, the sample may appear clear. Brown or red discoloration may herald the presence of red blood cells in the ejaculate (hematospermia). Drugs such as pyridium or methylene blue may lend semen an orange or blue color, respectively. Semen Volume
Ejaculate volume should be determined with a graduated pipette. Normal ejaculate volume typically ranges from 2.0 to 5.0 mL. The majority of the seminal fluid comes from the seminal vesicles (1.5 to 5.0 mL) and prostate (0.2 to 1.0 mL), with a small fraction from the bulbourethral gland (0.1 to 0.2 mL). The majority of ejaculated spermatozoa (0.2 mL) is contributed by the distal epididymis and represents less than 1% of the total ejaculate. The suffix -spermia refers to the volume of seminal fluid. A man is aspermic if he produces no semen after orgasm, hypospermic if he produces less than 0.55 mL of ejaculate, and hyperspermic if ejaculate volume is above 6.0 mL. The most common cause of low ejaculate volume is incomplete collection. Any abnormalities or interruptions during collection should be noted. Sample loss often compounds interpretation because distinct sperm-rich and sperm-poor fractions can be emitted. Short duration of abstinence from ejaculation may also lead to low semen volume. Hyperspermia is a rare clinical entity with unknown significance. Although spermatozoa density may be decreased, spermatozoa motility is unchanged.2 Semen pH
The semen pH should be recorded because it may be a useful parameter for diagnosis of some conditions affecting semen quality. Normal semen is alkaline, with a pH between 7.2 and 8.0.3 Values up to 8.5 have been noted in otherwise normal samples. Measurement is most easily performed with pH paper. Semen Liquefaction
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Fresh semen quickly coagulates into a gelatinous mass after ejaculation before liquefying over 5 to 25 minutes at room temperature. Coagulation is due to coagulating proteins contributed by the seminal vesicles in the final portion of the ejaculate;
secretions from the bulbourethral glands of Cowper and prostate present in the initial fraction of the ejaculate are responsible for liquefaction.4 An absence of coagulation may indicate absent or hypoplastic seminal vesicles, or ejaculatory duct obstruction. Conversely, prolonged liquefaction time may be due to a lack of prostatesupplied, liquefying proteases such as prostate-specific antigen, amylase, and plasminogen activators.5 Absence of liquefaction may cause infertility, although impaired liquefaction is frequently associated with normal fertility. Semen Viscosity
Viscosity of the liquefied ejaculate is evaluated by observing the flow of the sample while pushing the liquid through a needle or pipette. A normal sample will exit the device as discrete drops. Ejaculate with abnormal viscosity will form strands or threads greater than 2.0 cm in length. Similar to nonliquefaction, hyperviscosity may be treated by repeatedly passing the sample through a wide-bore needle or with the use of liquefying agents. Spermatozoa Concentration
Measurement of the number of spermatozoa in seminal plasma is a critical component of basic semen analysis. Spermatozoa concentration refers to the number of spermatozoa per unit volume of seminal fluid. This is generally expressed in terms of million of spermatozoa per milliliter (million/mL). Spermatozoa concentration alone does not provide a measure of total number of spermatozoa in the ejaculate. This value, the spermatozoa count, is calculated as the product of spermatozoa concentration and ejaculate volume. There are two well-established techniques for determining semen concentration, both procedures entailing the counting of an aliquot of liquefied semen in a specialized chamber. Regardless of the method utilized, it is imperative to ensure that the semen specimen is well mixed. Gentle agitation of the container is sufficient to ensure good mixing. Vigorous shaking or vortexing should be avoided. The concentration of spermatozoa in a semen sample can be measured using the Neubauer hemocytometer method. The Neubauer hemocytometer is one of several specialized counting chambers currently in use. Using a positive displacement pipette, both chambers are filled with well-mixed, diluted semen. The chamber is allowed to stand for 5 minutes to allow the cells to sediment. Only distinct spermatozoa within the grid are counted. If isolated heads, tails, or other germinal cells are noted, they should not be counted. After counting one side of the chamber, the second grid should be counted. The two estimates should be averaged; if each count is not within 5% of the average, both should be discarded and another hemocytometer prepared. If both counts are within 5% of their average, the average is divided by the surface area counted and multiplied by the dilution factor to yield the spermatozoa concentration in the original semen sample (millions/mL). The spermatozoa count may then be calculated by multiplying spermatozoa concentration and ejaculate volume. The Makler counting chamber (Sefi Medical Instruments, Haifa, Israel) is a specialized instrument designed for rapid semen analysis. Since its inception in 1980, the Makler counting chamber has gained wide acceptance and is used in many laboratories. The main advantage of the Makler counting chamber over the
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Chapter 39 Assisted Reproductive Technology: Laboratory Aspects Neubauer hemocytometer is that except in cases of extremely high spermatozoa concentration, no dilution of the semen specimen is needed. Additionally, motility and forward progression may be assessed at the time of spermatozoa concentration determination. Although the Makler Chamber simplifies determination of spermatozoa concentration in semen analysis, the method lacks the accuracy of traditional hemocytometry and may be prone to errors.6 The suffix –zoospermia refers to the presence of spermatozoa in the ejaculate. Patients with concentrations less than 20 × 106/mL are classified as oligozoospermic. Men with no spermatozoa present in the ejaculate are deemed azoospermic. Azoospermia is diagnosed only after microscopic confirmation of the absence of spermatozoa in the centrifuged pellet of an undiluted sample of semen. Spermatozoa Motility and Forward Progression
Although the total number of moving spermatozoa is an important indicator of fertility potential, the quality of the spermatozoa movement must also be assessed. As such, both quantitative and qualitative measures of spermatozoa motility are routinely recorded. Motility and progression assessment of the spermatozoa should be performed within 1 to 2 hours of production, with care taken to keep the sample at room or body temperature to avoid decreases in spermatozoa motility. For quantitative assessment, at least 200 spermatozoa in five separate viewing fields are classified as exhibiting normal movement, abnormal movement, or no movement. Spermatozoa motility is calculated as the percentage of total spermatozoa that demonstrate flagellar motion. In addition to quantitative assessment, several rating systems are used to evaluate the progressive character of spermatozoa movement. Some rank the progression of individual spermatozoa and count them separately; others hold progression as a modal component of motile spermatozoa. The World Health Organization (WHO) 1999 progression system classifies spermatozoa into one of four categories: A represents spermatozoa with rapid progressive motility; B, slow or sluggish progressive motility; C, nonprogressive motility; and D, no motility.7 The percentage of spermatozoa in each category is reported. A normal semen specimen contains at least 50% motile spermatozoa with the majority exhibiting good (modal progression class >2, WHO class A and B) forward progression. Athenozoospermia is defined as less than 50% of spermatozoa with good motility. Spermatozoa Morphology
Assessment of spermatozoa morphology provides a sensitive indicator of the quality of spermatogenesis and fertility potential. Many structural abnormalities affecting spermatozoa are associated with infertility. Accurate morphologic characterization of the semen specimen is an important part of the semen analysis. Multiple systems of categorization of spermatozoa morphology are currently in use. Many systems are plagued by subjective interpretations of abnormality, which vary from observer to observer. Newer methods have attempted to standardize morphologic evaluation. In 1986, Kruger and associates proposed a strict criteria for classification of normal and abnormal spermatozoa morphology.8 Objective measurements of individual spermatozoa components are included in this system, also known as the Tygerberg strict
criteria classification system. According to this system, a spermatozoon is considered normal only if: (1) the head measures 5 to 6 microns in length and 2.5 to 3.5 microns in width; (2) acrosomal staining covers 40% to 70% of the anterior aspect of the sperm head; (3) the midpiece is 1.5 times as long as the head length and less than 1 micron in width; (4) the tail is approximately 45 microns long, uniform, uncoiled, and free from kinks; and (5) cytoplasmic droplets are no more than half the size of the spermatozoa head and occupy the midpiece only. Borderline forms are considered abnormal in this classification scheme. In men with spermatozoa counts greater than 20 million/mL and motility greater than 30%, fertilization rates during IVF cycles were 91% for men with greater than 14% normal spermatozoa by Tygerberg strict criteria and 37% for men with less than 14% normal forms.8 This study established the reference value for normal morphology as 15% or greater by strict criteria. In 1992, the WHO adopted a grading system based on the Tygerberg strict characterization of distinct spermatozoon components.3 Under these guidelines, a spermatozoon is considered normal if: (1) the head measures 4 to 5.5 microns in length and 2.5 to 3.5 microns in width; (2) acrosomal staining covers 40% to 70% of the anterior aspect of the sperm head; (3) there are no neck, midpiece, or tail defects; and (4) cytoplasmic droplets are less than one third the size of the head. Although these parameters appear quite similar to Tygerberg criteria, slightly looser standards increase the reference value for normal morphology to 30%. Use of both grading schemes varies from laboratory to laboratory. Spermatozoa Viability
Spermatozoa viability is tested by evaluating the capacity for the spermatozoa membrane to exclude dyes or other substances. Because the percentage of viable spermatozoa is usually slightly greater than that of motile spermatozoa, viability testing is usually performed only when motility is less than 40%. The eosin–nigrosin test is a common method for assessing viability. Intact cells exclude eosin dye (red); nonviable cells exhibit red staining. Nigrosin functions as a counterstain to visualize unstained live cells. Equal volumes of liquefied semen and eosin–nigrosin stain are mixed on a clean, dry microscope slide. The total number of spermatozoa that do not take up the stain is recorded as percent of viable spermatozoa in the sample. Another method for assessing spermatozoa viability is the hypo-osmotic swelling test. The test relies on the ability of live spermatozoa to tolerate moderate hypo-osmotic stress as evidenced by controlled swelling. Dead spermatozoa do not show discernible swelling when exposed to hypo-osmotic conditions, whereas viable spermatozoa exhibit a characteristic coiling pattern in the tail.9
Functional Spermatozoa Tests Despite normal semen parameters, spermatozoa may be functionally unable to perform all the requisite steps necessary for fertilization. Several tests have been developed to evaluate potential functional obstructions to fertility. The predictive value of these tests is questionable, however, and their usefulness in therapeutic fertility treatment is debatable, at best.
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Section 6 Infertility and Recurrent Pregnancy Loss Acrosome Reaction
Before fertilization, spermatozoa must undergo the acrosome reaction. The acrosome reaction involves the fusion of the acrosomal membrane with the adjacent plasma membrane. This fusion results in the release of acrosomal content. Evaluation of acrosome functional activity may be accomplished by mixing capacitated spermatozoa with inducers of the acrosome reaction. Spermatozoa are then evaluated using fluorescent stain to determine the status of the acrosomal membrane. Zona Pellucida Binding Assay
The zona pellucida binding assay is another adjunctive test of spermatozoa function. This test assesses the capacity of spermatozoa to bind to the outer surface of the zona pellucida, a prerequisite for binding and penetrating the egg. Microscopically, the zona pellucida is divided and each half is mixed with a sample of the patient’s spermatozoa or a sample of a fertile donor. Spermatozoa bound to the zona pellucida outer surface are counted. A hemizona index is calculated by dividing the total number of patient spermatozoa bound by the total number of donor spermatozoa bound. Successful IVF is associated with an index greater than 60%.10 Hamster Egg Penetration Assay
The zona pellucida, the acellular glycoprotein layer surrounding the ovum, regulates species-specific fertilization. Removal of this layer allows evaluation of interspecies, spermatozoa–oocyte interaction using the sperm penetration assay (SPA). This procedure assesses the ability of human spermatozoa to penetrate a hamster oocyte as a test of the fertilizing capability of the human spermatozoa.11 Human spermatozoa penetration of zonafree hamster oocytes has been shown to correlate with human spermatozoa penetration of human ova.12 Sperm Chromatin Structure Assay/Single-cell Gel Electrophoresis
Spermatozoa DNA integrity tests are useful in the evaluation of the haploid chromatin of the spermatozoa nucleus. Chromosomal quality is determined by both chromatin maturity and chromatin normalcy. Both the sperm chromatin structure assay (SCSA) and single-cell gel electrophoresis test (also known as comet assay) serve as tools for measuring clinically important properties of spermatozoa nuclear chromatin integrity. Assays utilize direct staining and evaluation of spermatozoa chromatin to assess the integrity of the genetic material. The tests provide useful information on the presence of genetic damage to spermatozoa DNA. Briefly, both procedures evaluate shifts from intact, double-stranded DNA to denatured, singlestranded DNA.13 These assays can be used to assess male spermatozoa DNA integrity as related to fertility potential and embryo development as well as effects of reproductive toxins.14
Collection-Specific Spermatozoa Evaluation and Processing
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For most healthy men, masturbation is a straightforward method of semen collection. For men with ejaculatory dysfunction or azoospermia, however, other methods of spermatozoa recovery are necessary for fertility evaluation or therapeutic maneuvers. Men who are unable to ejaculate may require clinical spermatozoa
collection; men with azoospermia may be aided by surgical intervention. Processing of Semen Collected by Masturbation
Exposure to seminal plasma results in decreased spermatozoa motility and viability. Prolonged exposure can irrevocably diminish the fertilizing potential of spermatozoa. To obtain the heartiest sample for both laboratory tests of spermatozoa function and clinical application, spermatozoa must be separated from the seminal plasma after ejaculation. There are three fundamental approaches to the separation of spermatozoa from seminal plasma: spermatozoa washing; spermatozoa migration, or swimup; and spermatozoa density gradient separation. These general spermatozoa processing techniques are applicable to both intrauterine insemination (IUI) and IVF procedures. Spermatozoa Washing
Spermatozoa washing is the most common method for the separation of spermatozoa from seminal plasma. Washing not only quickly and efficiently removes detrimental factors present within the seminal plasma, but also concentrates spermatozoa within the ejaculate. Spermatozoa washing is accomplished by mixing the ejaculate with an appropriate, protein-supplemented medium. Mixtures are then centrifuged and spermatozoa pellets form at the bottom of the container. The supernatant is carefully aspirated and the pellet is resuspended. This procedure can be recommended for samples with good concentrations of highly motile spermatozoa and very few nonspermatozoa contaminating cells. Spermatozoa Migration Techniques (Swim-up Method)
In the female reproductive tract, migration into the periovulatory cervical mucus isolates a population of potentially functional spermatozoa. Although simple washing removes seminal plasma from a semen sample, it does nothing to accomplish this goal. Techniques that enrich the population of motile or morphologically normal spermatozoa from a sample may be utilized for IUI or IVF, and include the classic swim-up procedure. In the spermatozoa swim-up procedure, the innate ability of motile spermatozoa to migrate against gravity is used to enrich for motile spermatozoa. Two different methods of swim-up separation are commonly used. In the first (swim-up from semen), freshly liquefied semen is split into several fractions and placed in tubes beneath a layer of low-viscosity culture medium. In the second method (swimup from pellet), fresh semen is first washed and pelleted. The supernatant is removed and medium is gently layered over the pellet. In both methods, motile spermatozoa naturally migrate from the lower layer (fresh semen or pelleted spermatozoa) into the overlying culture medium during incubation at 37° C. Spermatozoa washing of a sample before enrichment for motile spermatozoa (swim-up from pellet) has been criticized because dead and abnormal spermatozoa present in the original sample remain in the pellet. Aitken and Clarkson showed that the functional fertilizing capacity of motile spermatozoa isolated from such a pellet can be impaired when compared to that of motile spermatozoa isolated before spermatozoa washing and pelleting.15 The authors propose that the production of oxygen free radicals by abnormal spermatozoa in the pellet may result in cellular damage in motile spermatozoa, leading to abnormal spermatozoa function. Additionally, the centrifuged pellet has a
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Chapter 39 Assisted Reproductive Technology: Laboratory Aspects relatively small interface with the overlying layer, making it difficult for motile spermatozoa in the bottom of the pellet to migrate into the media. Density Gradient Separation
Density gradient separation relies on a density gradient coupled with centrifugation to separate fractions of spermatozoa based on motility, size, and density. Various techniques have been described using continuous or discontinuous (discrete layers interrupted by defined interfaces) gradients. A variety of commercially available gradient materials are in use. An aliquot of the spermatozoa sample is gently layered over gradients of such a material and centrifuged. The resulting pellet is washed in culture medium before resuspension in medium at the desired concentration. Additionally, one can perform density gradient separation and washing followed by spermatozoa swim-up in bicarbonatebuffered media at 37° C in a CO2 incubator to select for a highly motile population of spermatozoa for insemination in IVF. Processing of Spermatozoa Collected Following Retrograde Ejaculation
Retrograde ejaculation involves the flow of semen into the bladder during orgasm. During normal ejaculation, the urinary sphincter remains closed to guard against retrograde expulsion of semen into the bladder. If the sphincter is incompetent or otherwise nonfunctioning, semen may preferentially travel back into the bladder rather than through the urethra. Retrograde ejaculation is a rare cause of male infertility. It should be suspected in patients with oligospermia or aspermia. Any condition that interferes with the sympathetic innervation of the bladder neck or vas deferens may result in retrograde flow. The condition is diagnosed by examining postejaculate urine for spermatozoa. The presence of 10 to 15 spermatozoa/HPF confirms the diagnosis and differentiates retrograde ejaculation from anejaculation. Viable spermatozoa may be retrieved from the urine of patients failing medical therapy.16 Because urine’s acidity makes it naturally toxic to spermatozoa, it is first suggested to alter the chemical milieu of the bladder to minimize its deleterious effects on spermatozoa quality. Alkalinization of the urine above a pH of 7.5 can be achieved by instructing the patient to ingest sodium bicarbonate for several days prior to collection. The patient empties the bladder before masturbation. Immediately after orgasm, the patient urinates into a sterile container, which is taken to the laboratory for spermatozoa extraction. Alternatively, for men unable to volitionally void, the bladder may be catheterized and washed with fresh, pH-adjusted, spermatozoa processing medium. After irrigation, a small volume of medium is left in the bladder. The patient masturbates and ejaculates, and the bladder is catheterized again to obtain fluid containing retrograde ejaculate, which is collected and transported to the laboratory for processing. Laboratory procedures begin with centrifugation and removal of urine from the spermatozoa. The resuspended pellet can then be processed as previously described for samples produced from masturbation. Processing of Spermatozoa Collected Following Vibratory Stimulation/Electroejaculation
Failure of emission is termed anejaculation. Causes of anejaculation are similar to those of retrograde ejaculation, although spinal cord injury is a much more common cause. Because most of
these patients do not respond to sympathomimetic therapy, they may require the use of external stimulatory devices to achieve emission. The most common methods of stimulation are penile vibratory stimulation and rectal electroejaculation. Penile vibratory stimulation entails the application of a penile vibrator to the glans penis, leading to a reflexive ejaculation. This technique induces ejaculation in approximately 70% of anejaculatory men with spinal cord injuries.17 Men with lesions above the level of T10 are more likely to respond than those with lesions below that level. Electroejaculation may be used in men who do not respond to vibratory stimulation. This procedure involves carefully inserting a probe into the rectum, followed by the intermittent application of electrical current to the periprostatic nerve plexus. The current stimulates the muscular tissue of the prostate, seminal vesicle, vas deferens, and epididymis to contract and propel semen into the urethra. It is successful in approximately 75% of patients.18,19 If antegrade ejaculation ensues, it may be collected from the urethra. If retrograde ejaculation occurs, then the urine is alkalinized beforehand and the bladder irrigated with medium and catheterized to remove any spermatozoa-bearing fluid. Risks of electroejaculation include rectal thermal injury or perforation. The rectum should be examined with proctoscopy before and after the procedure. Life-threatening autonomic dysreflexia, or massive, uncoordinated sympathetic release, may occur in patients with spinal cord injuries above the level of T6. Blood pressure monitoring is imperative in this patient population. Semen obtained by vibratory stimulation and electroejaculation frequently has low volume, high spermatozoa concentration, and poor motility, likely owing to stasis within the genital tract.20 Again, processing of samples produced with vibratory stimulation or electroejaculation continues as in samples produced with masturbation. Processing of Spermatozoa Collected Following Surgical Spermatozoa Collection
The management of severe male factor infertility has been dramatically changed with the introduction of intracytoplasmic sperm injection (ICSI). Because only one spermatozoa is needed to inject into each oocyte, few spermatozoa are needed to ensure fertilization of retrieved oocytes with ICSI. Advances in surgical techniques of spermatozoa retrieval combined with ICSI have allowed men with certain male infertility factors previously considered to be incompatible with fertility to father biologic progeny. Spermatozoa may be retrieved in men with both nonobstructive and obstructive azoospermia. Chapter 53 discusses the technical details of the specific surgical procedures. Various surgical techniques have been refined to collect viable spermatozoa from the epididymis and testes. Because low quantity and quality spermatozoa are usually recovered, specialized processing is required when ICSI is indicated. Microsurgical Epididymal Sperm Aspiration
Microsurgical epididymal sperm aspiration (MESA) is indicated for men with reconstructible or nonreconstructible obstructive azoospermia. It is a relatively simple procedure requiring regional or general anesthesia. MESA involves direct exposure of the epididymis with microscopic retrieval of spermatozoa from that structure. An incision is made through the scrotal skin, dartos, and tunica vaginalis to expose the testis and epididymis. A small
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Section 6 Infertility and Recurrent Pregnancy Loss incision is made in the wall of an epididymal tubule, and a needle or hollow glass rod is used to aspirate fluid from the lumen. Although pregnancy rates are similar, MESA is preferred to the other, less-invasive method of epididymal spermatozoa extraction, percutaneous epididymal sperm aspiration (PESA), because it provides the setting to correct reconstructible etiologies of azoospermia identified at the time of exploration. Additionally more spermatozoa are recovered with MESA than PESA.21 Testicular Sperm Extraction/ Testicular Sperm Aspiration
Testicular sperm extraction (TESE) is an effective procedure for the retrieval of spermatozoa for ICSI. It is indicated in men with nonobstructive azoospermia as well as men with obstructive azoospermia in whom spermatozoa could not be retrieved from the epididymis.22 TESE entails testicular biopsy with retrieval of spermatozoa. An incision is made through the scrotal skin, dartos, and tunica vaginalis to expose the testis. The tunica albuginea is then opened. The testicle is gently squeezed to deliver seminiferous tubules through the incision. Several tubules are cut and immediately placed in medium for processing. Testicular sperm aspiration (TESA) is a simple, percutaneous procedure that utilizes a small-gauge needle and syringe to retrieve testicular tissue. The procedure is the least invasive of the testicular spermatozoa retrieval methods and can be performed in the office setting under local anesthesia. It is indicated in patients with obstructive azoospermia. In this procedure, a finegauge, beveled needle attached to a 10-mL syringe is inserted through the scrotal skin into the anterior testis. Back-pressure is applied to the syringe while the needle is gently moved back and forth until tissue is aspirated into the syringe. The needle is withdrawn and the tissue is transferred into sterile medium, which can then be sent for processing. Microscopic Testicular Sperm Extraction
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Microscopic testicular sperm extraction (microTESE) is a relatively new procedure designed to maximize the yield of testicular spermatozoa from men with nonobstructive azoospermia while minimizing the amount of tissue excised.23 Testicular microdissection has several advantages over the standard, open procedure. Use of the operating microscope allows for visualization of small blood vessels and minimizes the risk of injury to blood supply. Additionally, spermatozoa production in patients with nonobstructive azoospermia is not constant throughout the testis, with isolated areas showing spermatogenesis even while the majority of the tissue is quiescent. Schlegel’s discovery that tubules with active spermatogenesis appear larger and fuller than nonactive tubules with microscopy make microTESE a much more sensitive procedure than TESE for identifying active areas. Much smaller volumes of tissue are needed for spermatozoa retrieval, avoiding the impairment in testosterone production that may occur after removal of larger amounts of tissue with TESE.24 As in TESE, the testis is exposed and the tunica vaginalis is opened. An operating microscope is used to identify a relatively avascular area on the anterior surface of the tunica albuginea. A “microknife” is used to make a small incision in this area. The seminiferous tubules are expressed through the incision and careful dissection is used to identify large, full tubules. If such a tubule is encountered, it is excised with sharp, curved scissors.
The sample is placed in medium and examined under microscopy for the presence of spermatozoa after microdissection. If spermatozoa are not found other areas or, if necessary, the contralateral testis is examined. Spermatozoa found in the epididymis and testis are not fully mature. Those isolated from these structures may exhibit some movement. However, specimens retrieved from the testis are frequently immotile. Motility of epididymal- and testicular-derived spermatozoa, reflecting viability, is a critical factor in predicting the success of ICSI. Additionally, testicular spermatozoa are enclosed within the surgical specimen and must first be released before subsequent processing. Methods for recovery and maturation of surgically retrieved spermatozoa have been described.25 In MESA, the aspirate is flushed in a small volume of medium. If spermatozoa are present, an aliquot should be used for concentration and motility determination. If present, fresh epididymal spermatozoa may be used for injection or cryopreservation. For testicular-derived samples, the collected tissue is flushed into a small volume of medium and minced with sterile scissors. Using microscopy, each seminiferous segment is slit with a small-gauge needle and “milked” to tease any spermatozoa present into the medium. The seminiferous tubule contents are then pipetted through a finely pulled glass pipette to produce a singlecell suspension. A portion of this is assessed for spermatozoa. If spermatozoa are present, care is taken to minimally dilute the sample yet to suspend the sample in media before 24- to 48-hour culture to enrich for a population of motile spermatozoa.
Spermatozoa Preservation Cryopreservation of human spermatozoa became a feasible method of storage in 1949, when Polge discovered that fowl spermatozoa could be protected from the effects of freezing by the addition of glycerol. Soon after, Sherman described successful cryopreservation and thawing of human spermatozoa with subsequent pregnancy.26 Since that time, a large body of research has focused on understanding the physical and chemical changes that occur during freezing and in evaluating methods and agents to optimize freezing. Although many advanced aspects of cryobiology are beyond the scope of this text, several basic principles are important to discuss. Cryopreservation has become an important component of ART. Patients with ejaculatory dysfunction requiring vibratory stimulation or electroejaculation may freeze spermatozoa and use aliquots to attempt fertilization over several cycles without the need for repeat procedures. It has been recommended that surgically retrieved spermatozoa be cryopreserved for future cycles of IVF with ICSI to obviate the need for repeat procedures.27 Donor insemination relies on the reliable, prolonged storage of large numbers of samples. Patients facing potentially fertilitydamaging medical therapies may choose to store spermatozoa for future use.
OOCYTES: PREPARATION AND EVALUATION Advances in culture medium composition have significantly influenced embryo quality and pregnancy rates over the years. All media for ART can now be purchased commercially. Before use they must be tested for toxins and their ability to support
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Chapter 39 Assisted Reproductive Technology: Laboratory Aspects the growth and development of embryos. Media should only be opened in a laminar flow hood, with attention to maintaining sterility during the addition of protein. After any media preparation or addition, it should be filtered for assurance of sterility.
the CO2 environment before use. Overlaying of the medium with mineral oil is recommended to help avoid evaporation and increase stability of pH while the dish is temporarily out of the CO2 environment. Oil overlay provides an effective barrier to atmospheric volatile organic compounds, which can be embryotoxic if exposed directly to the culture medium.
Oocyte Processing Area A great deal of consideration must be made to the setup of the laboratory to ensure the best results for all procedures. The laboratory should be as close as possible to the procedure room where oocyte retrievals and embryo transfers are taking place. It needs to be a controlled environment devoid of environmental toxins. It may be recommended that the laboratory have positivepressure airflow; the temperature and lighting need to be controlled for optimal results. A laminar flow hood is indispensable for any preparation of media and manipulation of gametes and embryos. All equipment in the IVF laboratory must be monitored daily for proper performance. A stringent quality control program is essential for the assurance of consistent results in an embryology laboratory. All media, equipment, and other materials such as dishes and pipettes that will come in contact with gametes and embryos should be biocompatible with mammalian embryos. The mouse embryo assay can be used to detect toxins, suboptimal quality, or suboptimal culture conditions. This assay consists of the culture of mouse embryos from the zygote stage until the blastocyst stage in laboratory test conditions.
Laboratory and Media Preparation There are two basic kinds of media used for ART procedures, one used during the handling of gametes and embryos out of the CO2 incubator, called processing medium, and another used for culture while in CO2 incubators, called culture medium. Both consist of a combination of nutrients necessary to maintain early embryo metabolism and proper pH and osmolarity. A source of protein must be added, such as albumin or synthetic serum, in a percentage that can vary from 2 to 15 mg/L. This addition of protein is not only important for the stability of osmolarity and pH, but it also helps with the manipulation of oocytes and embryos by reducing cell attachment to any surface, as is their natural tendency. Processing media are modified culture media, with the addition of a buffer called HEPES, capable of maintaining medium pH at a stable state out of the CO2 incubation. HEPES, however, is known to alter ion channel activity in the plasma membrane and may have a degree of toxicity relative to exposure concentration, temperature, and time. For this reason it is recommended to minimize exposure time of cells to HEPES-buffered media. The addition of an anticoagulation factor, such as heparin, in low concentrations, may be recommended for the processing medium used at oocyte retrieval to help avoid formation of clumps of coagulated blood. These coagulants can make it difficult to visualize the oocyte–cumulus complex. Media used for the culture of embryos are usually bicarbonatebuffered and kept in an incubation chamber. It is important that this medium be maintained at a stable pH and temperature, because embryos are extremely sensitive to variations of these two factors. Culture media, used for embryo development inside incubation chambers, should always be equilibrated inside
Oocyte Collection and Evaluation Before oocyte retrieval, it is necessary to set up the laboratory to allow optimal conditions for rapid, efficient, and safe oocyte collection and placement within an incubator. Proper setup minimizes variations in oocyte environment outside of the incubator. Room Conditions
It is important to ensure that all room conditions in the laboratory are stable before oocyte collection. All surfaces should be clean and warming blocks should be maintained at 37° C to maintain the temperature of the tubes used for the follicular fluid collection. It is recommended that all pipettes and dishes be rinsed with culture medium before use. Media
It is recommended that both processing and culture media be prepared the day before the oocyte retrieval. Culture medium dishes should be prepared and kept in the CO2 incubator overnight. Processing medium must be warmed in a waterbath or dry incubator before use. All media should be kept at 37° C during ART procedures. Oocyte Collection
Tubes containing processing medium plus heparin, to prevent clotting, should be prepared. Using sterile technique, these are placed in a warming block in the room where the collection will be performed by the physician. The aspirated follicular fluid is collected by the physician into processing medium containing protein at 37° C and immediately transported to the laboratory. In the laboratory, aspirates are examined quickly for the presence of cumulus–oocyte complexes. When an oocyte is identified, it is rinsed in processing medium, quickly graded, and placed in a pre-equilibrated culture dish in the CO2 incubator. This process must be as fast and efficient as possible. In cases where the laboratory and egg collection rooms are separated by significant distance, the laboratory staff may employ mobile equipment to conduct the egg search in the egg collection room and to provide adequate conditions for oocytes during transit back to the laboratory. A modified pediatric isolette fitted with a microscope is commonly used for this purpose. Oocyte Assessment
Oocyte–cumulus complexes are scored before incubation. Accurate assessment of oocyte maturity at the time of the retrieval may be informative for timing and success of fertilization and may permit identification of some oocyte abnormalities. Initial oocyte grading relies on direct optical analysis of oocyte– cumulus complex morphology. The grade is based on characteristics of the cumulus oophorus and corona radiata. This first observation should be made quickly while searching through the follicular fluid. In cases of IVF by conventional insemination,
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the cumulus is not removed before insemination, so observation is somewhat limited. Immature oocytes are defined as being at a stage of meiosis prior to metaphase of meiosis II. This includes oocytes in prophase of meiosis I, which are identified by the presence of a germinal vesicle or nuclear envelope in the cytoplasm, without any polar body present in the perivitelline space (Fig. 39-1). If present, cumulus and corona are commonly very tightly condensed. As prophase I resumes, the oocyte enters into metaphase of meiosis I. This intermediate stage of maturation is recognized by the disappearance of the germinal vesicle and the absence of the first polar body (Fig. 39-2). For meiosis I oocytes the cumulus may be expanded, but the corona can still be compact. The extrusion of the first polar body marks the transition to a mature
oocyte, which is now considered to be at meiosis II (Fig. 39-3). Metaphase II oocytes will usually have a fully expanded cumulus. Under normal circumstances the oocyte will remain at meiosis II until fertilization, when meiosis II resumes, the second polar body is extruded, and the male and female pronuclei form (Fig. 39-4). Assessment of oocyte morphology after cumulus cell removal may reveal its true morphologic quality. The appearance of cytoplasm, zona pellucida, and polar body should be considered. A homogeneous cytoplasm, with uniform color and granularity and occupying most of the space inside the zona pellucida, represents a good quality oocyte. Vacuoles, a dark color, shrunken shape, or granularity are considered negative signs in the morphological quality evaluation of oocytes. It may be important to observe
Figure 39-1 Germinal vesicle intact or immature human oocyte after cumulus removal. (Courtesy of Kathleen A. Miller, Reproductive Medicine Associates of New Jersey, Morriston, N.J.)
Figure 39-2 Metaphase I human oocyte without a polar body after cumulus cell removal. (Courtesy of Kathleen A. Miller, Reproductive Medicine Associates of New Jersey, Morriston, N.J.)
Figure 39-3 Metaphase II (mature) oocyte. A, Oocyte–cumulus cell complex. B, Denuded oocyte showing presence of first polar body. (Courtesy of Kathleen A. Miller, Reproductive Medicine Associates of New Jersey, Morriston, N.J.)
B
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Figure 39-4 Normal zygote showing presence of two polar bodies and two pronuclei. (Courtesy of Kathleen A. Miller, Reproductive Medicine Associates of New Jersey, Morriston, N.J.)
shape and thickness of the zona pellucida; it should not be cracked and should have an appropriate thickness for its developmental stage. There are many oocyte morphologic grading systems. The folllowing is an example of one based on visual appearance: 0 = Atretic oocyte, degenerate. 1 = A germinal vesicle (GV) is present. The oocyte is very immature. 2 = The corona is tight/dark, but no GV is present. The cumulus is starting to loosen, but the oocyte is hard to visualize. The oocyte is still immature. 3 = The corona is radiating and loosening, the cumulus is loose and dispersed. The oocyte is visible, but the first polar body is still not present. The oocyte is still immature but likely will extrude a polar body within a few hours. 4 = The optimal level of maturity for insemination. The oocyte has fully expanded cumulus and the first polar body is visible.
the true measure of successful oocyte in vitro maturation is complete nuclear maturation and ability to fertilize and develop into an embryo that is capable of supporting a live birth. In vitro maturation of human oocytes was first demonstrated by Dr. Edwards in 1965. Although this technique was viewed as having great potential in providing oocytes for early IVF work, the use of exogenous gonadotropin administration proved more efficient and became the gold standard in infertility treatment. Because of the numerous perceived advantages of in vitro maturation, continued interest and investigation have persisted in the area of human oocyte in vitro maturation. Pregnancies have been reported using in vitro maturation of immature oocytes that were retrieved after conventional follicle-stimulating hormone (FSH) stimulation and hCG administration.28–30 However, such an approach minimizes the advantages that warrant in vitro maturation. In addition, it could be argued that such an approach represents pseudo in vitro maturation of oocytes because the exogenous gonadotropins and resulting follicular development most likely progressed oocytes’ cytoplasmic maturation while nuclear maturation lagged. Recent reports have utilized a single dose of hCG (no exogenous FSH administration) on day 10 to 14 of the cycle with oocyte isolation 36 hours after hCG administration.31,32 These studies were performed in patients with polycystic ovary syndrome (PCOS). In this subpopulation the use of single-dose hCG administration coupled with in vitro maturation and ICSI appears to be an efficient means of treating infertility while reducing the cost and concerns of hyperstimulation syndrome. Although the numbers in the study are small, the resulting clinical pregnancy rate is encouraging, at approximately 39%.32 Whether such a treatment regimen will work in non-PCOS patients remains to be determined. At the other extreme, true in vitro maturation entails collection of oocytes from ovaries without exogenous gonadotropin stimulation. Such an approach will, when it becomes efficient, allow realization of all the perceived advantages of in vitro maturation. Clinical pregnancies using in vitro maturation without exogenous gonadotropin stimulation have been reported.33–35 These results suggest that using an approach of in vitro maturation of human oocytes, coupled with IVF, is a means of obtaining live births. However, this technique requires extensive evaluation because the cumulative success in all of these studies, as determined by live births, is less than 5%. Numerous factors individually, or in combination, may be contributing to the poor success of IVF after in vitro maturation. These include oocyte quality, culture conditions, and endometrial receptivity.
IN VITRO MATURATION OF OOCYTES In vitro maturation of oocytes is the act of culturing and maturing oocytes that have been harvested at an immature state. What is unclear in this definition are the starting material and the endpoint measurements. One must be extremely cautious in extrapolating and comparing data regarding in vitro maturation of oocytes from exogenous hormone-stimulated cycles, human chorionic gonadotropin (hCG)-only-primed cycles, and nonstimulated cycles. Although the starting materials (immature oocytes) from each of these cycle categories may look the same at the light microscope level, their degree of cytoplasmic maturation and thus fertilization and embryonic developmental competence can be very different. In addition, from the definition,
IN VITRO FERTILIZATION IVF is the procedure in which oocytes and spermatozoa are obtained from a couple, with the combination of gametes taking place in a laboratory. The aim of this procedure is to produce embryos that can ultimately give rise to a viable pregnancy and healthy offspring. Spermatozoa are obtained by abovementioned methods.
Conventional Insemination If spermatozoa are of sufficient quality and quantity, IVF can be attempted with conventional insemination. Although the terms
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Section 6 Infertility and Recurrent Pregnancy Loss of sufficient quality and quantity are indeed subjective, each laboratory will have its own criteria for when a couple uses conventional insemination or ICSI to achieve fertilization. Spermatozoa can be processed in numerous manners or with a combination of techniques. The primary goal is to remove seminal plasma and isolate motile spermatozoa of normal morphology with as little nongamete cellular contamination as possible. The processes used include semen washing, density gradient separation, and swim-up procedures. Independent of the method of spermatozoa recovery, it is advised to incubate spermatozoa for approximately 4 hours in culture medium containing a protein source in a CO2 incubator to allow capacitation of spermatozoa. Capacitation is defined as the spermatozoa gaining the ability to bind to the oocyte’s zona pellucida, penetrate the zona pellucida and oolemma, and ultimately fertilize the oocyte. Just before insemination the spermatozoa sample should be assessed for concentration and percent motility. With these values, one can calculate the volume of insemination medium containing spermatozoa that will equate to the desired insemination spermatozoa number. Oocytes are routinely inseminated 3 to 6 hours after oocyte retrieval is performed, taking into consideration their level of maturity for the proper time of incubation. Oocytes can be inseminated in groups or individually. Groups of oocytes can be incubated and inseminated either in organ culture dishes, fourwell dishes, or test tubes containing equilibrated medium with or without oil overlay. Individual oocytes can also be inseminated in 30- to 50-μL drops of equilibrated medium in culture dishes with oil overlay. This reduces the number of spermatozoa necessary for the insemination. The final concentration of motile spermatozoa used for conventional insemination will differ between laboratories based on personal experiences. Concentrations that are too high can result in increased incidence of polyspermic fertilizations (more than one spermatozoon penetrating an oocyte). Concentrations that are too low may compromise fertilization rates. Generally concentrations range from 50,000 to 100,000 motile spermatozoa/mL. These numbers may be adjusted in cases of suboptimal parameters of motility or morphology.
Intracytoplasmatic Sperm Injection ICSI consists of insertion of a single spermatozoon directly into the oocyte cytoplasm. This technique was first successfully applied to human oocytes in 1994 and has since revolutionized the treatment of severe male factor infertility. By injecting a spermatozoon into the oocyte cytoplasm, many steps of spermatozoa processing and developmental prerequisites are bypassed without compromising fertilization rates. There is currently debate as to when to perform ICSI. Some programs utilize the procedure quite freely, whereas others are more conservative. Evidence strongly supports the following indications for the use of ICSI: ●
●
●
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Couple has had a prior failed fertilization by conventional insemination. Total motile spermatozoa concentration is less than 10 million/mL. Spermatozoa morphology is less than 4% normal forms based on strict criteria (this may depend on other semen parameters such as concentration, motility, and volume).
Technique
The equipment for ICSI, as in any other micromanipulation procedure, consists of an inverted phase contrast microscope with micromanipulators and injectors, which permit the manipulation and cellular surgery. A warming stage may be recommended on the microscope for maintenance of a consistent temperature, although some groups show quite acceptable results without using a warming stage for micromanipulation.36 The hydraulic system in a micromanipulator should work with maximal precision, and the microscope should be placed in a very stable location. Removal of the cumulus and corona radiata cells surrounding the oocytes (denuding) is essential for ICSI. The cumulus cells need to be removed so that they do not interfere with visualization of the egg or the injection. Two needles may be used to separate most of the cumulus cells by “cutting” the cumulus off and leaving the gamete with just a few cells attached. The oocytes, now almost free of cumulus cells, can be exposed for up to 30 seconds to a solution of processing medium containing 80 IU/mL of hyaluronidase and manually pipetted to remove remaining cells. The oocytes are then immediately washed in processing medium without hyaluronidase by repeated pipetting with a pulled pipette with an inner diameter just larger than the oocyte. Dishes for the actual injection can be made in many ways. The procedure can be performed in 5-μL microdrops of processing medium supplemented with protein, overlayed with mineral oil in a shallow culture dish. A 5-μL drop of a 7% polyvinylpyrrolidone (PVP) solution in processing medium can be placed in the center of the ICSI dish. Just before beginning the injections approximately 1 μL of spermatozoa suspension is added to the PVP drop. The high viscosity of this solution slows down spermatozoa movement and facilitates immobilization and aspiration. Additionally, it helps to prevent spermatozoa from sticking to the inside of the injection pipette. At the time of injection, denuded oocytes are placed one per drop into 5-μL microdrops around the 5-μL microdrop of PVP containing processed spermatozoa. Only a couple of oocytes should be added to the dish at a time to avoid prolonged exposure to the environment outside an incubator. Spermatozoa are aspirated from the drop using the injection pipette. A morphologically normal-appearing, motile spermatozoon is identified and the tail is broken using the injection pipette with a slashing motion against the bottom of the dish. The spermatozoon is then aspirated, tail first, into the pipette in preparation for ICSI and the pipette is moved into the drop with the oocyte. The holding pipette is used to manipulate the oocyte into position with the polar body in the 12 or 6 o’clock position. Negative pressure is applied to the pipette to hold the oocyte in place for the injection. The injection pipette is positioned in accordance with the outer border of the oolemma on the equatorial plane at 3 o’clock. The spermatozoon is then brought to the tip of the pipette, which is pushed against the zona pellucida. The needle is pushed forward through the zona pellucida and into the oolemma. Gentle suction is applied when the tip is believed to have penetrated the oolemma and a small amount of ooplasm is aspirated to ensure that the membrane has been breached. The spermatozoa is then released into the ooplasm and the pipette is removed. Injection of any extra medium should be avoided. A timeline schematic of the entire ICSI process is depicted in Figure 39-5.
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Chapter 39 Assisted Reproductive Technology: Laboratory Aspects ICSI FLOW CHART
Hours
0
Prepare micromanipulator holding pipette & injection needle
2
Ooctye retrieval
Prepare ICSI microinjection dishes (5 μl drops & microdrop dishes (20 μl drops)
Oocytes + Hyaluronidase Sperm sample Denude oocytes of cumulus cells Sperm processing Wash oocytes
6
Place one egg into each microdrop
Add sperm suspension to PVP microdrop
Hold egg by suction on holding pipette with polar body @ 6 or 12 o' clock
Select, break tail & aspirate sperm cell into injection needle
Inject sperm into ooplasm of egg
8
Move injection needle into an egg microdrop
Discharge egg from pipette, wash egg and put in fresh microdrop
Examine for ferilization: 2 PB, 2 PN
Incubate zygotes
Embryo replacement
Figure 39-5 Representative scheme of ICSI procedure. (University of Michigan ART Laboratory Procedures Manual.)
PREPARATION AND EVALUATION OF ZYGOTES AND EMBRYOS Fertilization The fertilization check of oocytes is performed 15 to 18 hours after insemination for both IVF and ICSI procedures. It is necessary to examine the oocytes/zygotes within this time period to visualize the presence of pronuclei and polar bodies. Fertilization checks before pronuclear formation or after their dissolution can lead to misclassification of a zygote as an oocyte not fertilized or to an inability to recognize abnormally fertilized oocytes. It is important that fertilization checks be performed rapidly yet efficiently. If oocytes have undergone conventional
IVF, the cumulus cells must be removed to clearly see the oocyte/zygote. This is done simply by repeatedly pipetting the oocyte/zygote with a pulled pipette with an inner diameter just larger than the oocyte or zygote. Normal fertilization is characterized by the presence of two pronuclei, one male and one female, in the ooplasm and two polar bodies in the perivitelline space. Polar bodies may fragment, leading to the appearance of more than two. Abnormal fertilization may be represented by a polypronuclear zygote, which means more than two pronuclei in the ooplasm. Abnormal fertilization can be classified as polyspermic, due to the penetration of more than one spermatozoon, or polygynic, due to disturbance in the second meiotic division, retention of the second polar body, and formation of two female pronuclei. A polypronuclear zygote can develop as preimplantation embryos yet are genetically abnormal. This justifies the recommendation to discard all polypronuclear zygotes observed at fertilization check. Abnormal fertilization may also be represented by oligopronuclear zygotes. The term applies to zygotes that express a single pronuclei. Only one pronuclei and the presence of two polar bodies may be observed in some cases when the oocyte undergoes parthenogenic activation, or failure of the spermatozoa head to decondense. It is possible that a second pronuclei will develop later than the first one, and a repeat observation about 4 hours after the first check is recommended. Failed fertilization is represented by absence of pronuclei and the presence of one or two polar bodies that may be in the process of degeneration. Failure of the oocyte to fertilize can have many causes, including poor-quality oocytes, problems in the interaction between the gametes, spermatozoa acrosomal reaction problems, or suboptimal culture conditions.
Embryo Assessment Embryos can be assessed and graded daily while they are in culture. A standard morphologic method of grading is applied according to observations made on embryo development until their transfer to the uterus on day 3 or day 5 (blastocyst stage). There are numerous scoring systems proposed for embryo development. Criteria for grading include the rate of division as judged by numbers of blastomeres, size, shape, symmetry, appearance of the cytoplasm, and presence of cytoplasmatic fragments. Traditionally, embryo morphology has been used as a means of embryo selection for transfer or freezing. Timing of cleavages and formation of fragmentation can be documented. Below is an example of a cleavage-stage embryo two-step grading system that incorporates cell number and morphology: A: Minimum of four-cell by 40 hours postinsemination; minimum of eight-cell by 64 hours postinsemination. B: Minimum of two-cell by 40 hours postinsemination; minimum of four-cell by 64 hours postinsemination. C: Minimum of two-cell by 64 hours postinsemination. D: No minimums (lowest possible grade). Do not make subtractions. Subtract from the grade for irregularities as follows: ● ●
Spherical blastomeres with no fragmentation: No subtractions Spherical blastomeres with <20% fragmentation: Subtract 1 grade
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Slightly irregular blastomeres with <50% fragmentation: Subtract 2 grades Irregular blastomeres with >50% fragmentation: Subtract 3 grades
Examples of how to apply this classification are: A three-cell embryo with 15% fragmentation postinsemination: Reported as 3Cell/C ● A four-cell embryo with 10% fragmentation postinsemination: Reported as 4Cell/B ● A seven-cell embryo with 0% fragmentation postinsemination: Reported as 7Cell/B ● An eight-cell embryo with 0% fragmentation postinsemination: Reported as 8Cell/A ●
at 40 hours at 40 hours at 64 hours at 64 hours
It is important to note that evaluation and scoring by morphology alone can be subjective and may not necessarily reveal embryos with the best developmental potential. Currently, there are numerous groups working on translational research focused on noninvasive means of assessing embryos for biomarkers that are indicative of embryonic developmental competence and implantation potential. Such evaluation, in concert with morphology, and genetic analysis (see discussion of Preimplantation Genetic Diagnosis in this chapter) has enormous potential to reshape the practice of embryo selection in the future.
Embryo Culture With the improvement of culture systems and extended culture media, it is now possible to culture embryos to the blastocyst stage (day 5 or 6). Typically patients who are considered candidates for blastocyst transfer are young women (less than 36 years old) with good ovarian reserve or older patients with a high number of embryos in a cycle (more than 5). One of the most important factors influencing blastocyst culture and transfer success is the quality and quantity of embryos on day 3. An effective blastocyst grading system using both number and letter assignment based on degree of development and assessment of both the trophectoderm and the inner cell mass has been proposed.37 The program should consider advantages and disadvantages in each individual patient and cycle before considering the option of blastocyst culture.
Assisted Hatching
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One of the most common unsolved problems in IVF is the fact that embryos with apparently good developmental potential do not always implant. It has been proposed that this may be due to defects of the zona pellucida, uterine receptivity, extensive fragmentation, modifications after freezing and thawing, or even suboptimal culture conditions. Potential defects in the zona pellucida could be overcome by assisted hatching. In this procedure a controlled incision in the embryo’s zona pellucida can be applied in an attempt to improve embryo implantation. The basis of assisted hatching is the hypothesis that weakening the zona pellucida, either by drilling a hole through it or altering its stability, will promote hatching and implantation of embryos that potentially otherwise would not occur. This has become a widely applied technique, but its true value is still under discussion. There are two common methods of assisted hatching used clinically for embryos at the six- to eight-cell stage: acid Tyrode’s
solution and laser assisted hatching. Acid Tyrode’s solution can be prepared in the laboratory, following a standard protocol, and the pH adjusted to 2.5,38 or it can be commercially purchased. It is important to appreciate that use of this acid can be detrimental to the blastomeres closest to the point where the acid is applied. In cases of erroneous manipulation, it can compromise the viability of the embryo. In this procedure, an assisted hatching micropipette expels the acid close to the zona pellucida of the embryo, which is secured by a holding pipette. As soon as a hole is observed, rapid suction is applied to avoid excess acid in the perivitelline space and in contact with blastomeres. After the procedure the embryos must be washed several times before further culture. Use of a laser for assisted hatching may be considered by some to be less dangerous than use of acid Tyrode’s solution assisted hatching, but its application, if not precise, may cause thermal or mutagenic effects in the embryo. Both techniques have risks and mandate fine proficiency.
Preimplantation Genetic Screening Preimplantation genetic screening (PGS) was originally seen as a means to detect and avoid congenital diseases by evaluation of individual blastomeres of preimplantation embryos. This has value for couples with probability of having a child affected by some genetic disturbance. Initially, molecular PGS was employed for embryo sexing in couples at risk for X-linked diseases.39 Technically, PGS consists of two steps, including micromanipulation and biopsy, and DNA analysis of gametes or embryos. Micromanipulation for the biopsy includes the mechanical opening of the zona pellucida and retrieval of one or two polar bodies, in the case of diagnosis performed on oocytes or zygotes, or the retrieval of a blastomere in cases of biopsy of embryos. This procedure is briefly illustrated in Figure 39-6. For DNA analysis, there are two main techniques currently employed, polymerase chain reaction (PCR) for single-gene disease detection and fluorescence in situ hybridization (FISH) for aneuploidy. Single-Gene Defects
PCR allows the amplification of a specific DNA sequence. This is a cyclic process in which the number of DNA fragments doubles at each cycle, allowing the observation of specific genes or gene mutations through either radioactive labeling, ethidium bromide, fluorescent dye, or silver staining. Each PCR cycle is divided into three steps, for multiplication of primer-specific gene sequences. First, natent double-stranded DNA is denatured into single strands by exposure to high temperatures (>90° C). Second, the temperature is lowered, allowing annealing of sequence-specific primers to their matching sites on the single-stranded DNA. Third, thermostable polymerase adds and extends nucleotides from the site of primer annealing. Collectively, this process provides amplification of a specific gene, or mutation, if present. Even with the high number of copies generated with PCR cycle amplification, a single PCR procedure may yield insufficient genetic material for gene detection. Efficiency and specificity of the DNA amplification can be improved by using a nested PCR method that consists of a two-step procedure.40 It is of extreme importance to realize that many factors can influence the reliability of PCR analysis. It is essential that
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Chapter 39 Assisted Reproductive Technology: Laboratory Aspects Figure 39-6 Biopsy procedures before PGS. A, Polar body biopsy, showing removal of first and second polar bodies. B, Blastomere biopsy, showing removal of two blastomeres. (Courtesy of Kathleen A. Miller, Reproductive Medicine Associates, New Jersey, Morriston, N.J.)
A
B
Figure 39-7 Examples of FISH analysis micrographs. A, A normal female. B, Trisomy 21 (in green). (Courtesy of Kathleen A. Miller, Reproductive Medicine Associates, New Jersey, Morriston, N.J.)
A
B
numerous steps in quality assurance be implemented to protect against erroneous results and to ensure confidence in the final results. Fluorescent In Situ Hybridization
Another way to analyze chromatin for PGS is FISH. This method utilizes direct-labeled probes, with the specific annealing of fluorescent nucleic acid probes to complementary sequences of DNA in a fixed specimen in which chromatin or chromosomes have been isolated.41–44 Chromatin from polar bodies or blastomeres can be treated and fixed for FISH. Cells in this
procedure are fixed on a slide in a manner that ruptures the cell, removes the cytoplasmic material, and spreads and adheres chromosomes. These chromosomes are then hybridized or annealed to the chromosome-specific fluorescent probes. Using a fluorescent microscope one can count specific chromosomes and thus identify normal or abnormal chromosome numbers (Fig. 39-7). Currently, the most utilized FISH probes determine number of chromosomes 13, 16, 18, 21, 22, X, and Y in the cells.45 As is the case in PCR-based PGS, numerous controls and implementation of stringent quality assurance programs are essential for the laboratory performing FISH-based PGS.
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Section 6 Infertility and Recurrent Pregnancy Loss CRYOPRESERVATION Cryopreservation of gametes and embryos maximizes the success of conception in any IVF cycle and prevents waste of specimens. Currently, freezing of embryos is accepted and is considered an indispensable technology in most ART laboratories. Such importance has even been confirmed by the ethics committee of the American Society for Reproductive Medicine.46 It has been stated that an effective cryopreservation program can decrease multiple pregnancies, costs, and need for hormonal stimulation of additional cycles and prevention of embryo waste. However, it is important to realize that there are many ethical, religious, legal, and social implications to embryo storage. Some countries, such as Italy, Germany, Austria, Switzerland, Denmark, and Sweden, have restricted or forbidden cryopreservation of embryos.47
Technique Successful cryopreservation requires use of cryoprotectants, chemical substances that when added to any cryopreservation medium help protect cells from damage that may occur during cooling, storage, or warming–thawing of cells. Cryoprotectants are categorized into two groups, permeating and nonpermeating cryoprotectants, based on their capacity to penetrate the cell membrane. Permeating cryoprotectants are classically low molecular weight compounds that lower the freezing point and include glycerol, ethylene glycol, propylene glycol, and dimethylsulfoxide. Nonpermeating cryoprotectants aid in the osmotic shrinkage of cells before freezing and control rehydration during the warming process. Thus, these nonpermeating cryoprotectants, which are usually monosaccharides or disaccharides, are critical in tempering potentially detrimental effects of osmotic shock during the cooling and warming processes. Sucrose is the most commonly used nonpermeating cryoprotectant. Damage during the process of cryopreservation can occur as a result of cryoforces such as exposure time to toxic cryoprotectants, ice crystal formation, or osmotic shock during the cooling. There are currently two primary categories of gamete/ embryo cryopreservation strategies: slow-rate freezing and vitrification.
is continued for a period of time, followed by continued temperature drop at a rate of −0.3° C/minute until it reaches −32° C. At this point the containers can be plunged directly into liquid nitrogen for storage. Thawing takes place with exposure of the container to room temperature and then 37° C. Embryos are removed from the container and exposed to thawing solutions. The first solution typically contains a slight increase in the nonpermeating cryoprotectant. This aids in protection against osmotic shock and cell rupturing and in the removal of the permeating cryoprotectant. Subsequent thaw solutions contain reduced concentrations of propylene glycol.
Vitrification Vitrification is a form of rapid cooling that utilizes very high concentrations of cryoprotectant that solidify without forming ice crystals. Ice crystals are a major cause of intracellular cryodamage. The term vitrification is derived from the Latin word vitreous, which means glassy or resembling glass. Vitrification can be considered a nonequilibrium approach to cryopreservation originally developed for cryopreservation of mammalian embryos.48 The vitrified solids therefore contain the normal molecular and ionic distributions of the original liquid state and can be considered an extremely viscous, supercooled liquid. In this technique oocytes or embryos are dehydrated by brief exposure to a concentrated solution of cryoprotectant before the samples are plunged directly into liquid nitrogen. Application of vitrification for both oocytes and embryos is a current area of focus for many clinical, rodent, and domestic animal production laboratories. An excellent review of the history of vitrification and potential advantages is available.49 Independent of the means of cryopreservation, gametes or embryos are subsequently stored in liquid nitrogen at −196° C. At this temperature intracellular transition and reactions are suspended. Thus, from this viewpoint, the long-term storage of gametes and embryos is essentially indefinite. However, it has been suggested that background ionizing radiation, over many hundreds of years, could become damaging.
Slow-Rate Freezing
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Currently, the most popular methods of embryo cryopreservation are slow-rate freeze protocols. Numerous protocols vary in permeating cryoprotectants, nonpermeating cryoprotectants, and cooling and warming rates. For these reasons it is often difficult to generalize or compare cryopreservation results. The following is one general example of a cleavage-stage embryo slow-rate cryopreservation protocol. Prior to cryopreservation, embryos that meet the programspecific freeze criteria are selected and assigned to cryopreservation. After washing embryos through processing media with 12 to 15 mg/mL protein, they are exposed to the same media containing 1.5 mol/L of propylene glycol (propanediol) and then 1.5 mol/L propylene glycol plus 0.1 mol/L sucrose. Embryos are loaded into plastic straws or vials and placed in a programmable freezer, where they will be cooled at −2° C/minute from room temperature down to −4 to −6° C. After a period of 5 minutes of holding the temperature, a super-cooled object is pressed against the side of the container to induce “seeding.” The hold
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ART Laboratories are high-complexity laboratories due to the level of knowledge, responsibility, and precision needed to perform the necessary procedures. A thorough infertility evaluation requires analysis of two ejaculates collected at least 1 month apart because semen quality varies over time. The suffix -spermia refers to the volume of seminal fluid. Aspermia refers to no semen after orgasm; hypospermia refers to less than 0.55 mL of ejaculate. Semen normally liquefies over 5 to 25 minutes at room temperature. The suffix –zoospermia refers to the presence of spermatozoa in the ejaculate. Patients with concentrations less than 20 × 106/mL are classified as oligozoospermic. Men with no spermatozoa present in the ejaculate are deemed azoospermic. Athenozoospermia is defined as less than 50% of spermatozoa with good motility.
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Chapter 39 Assisted Reproductive Technology: Laboratory Aspects ●
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Using Tygerberg strict criteria, normal morphology is defined as 15% or greater. Using the WHO criteria, normal morphology is defined as 30% or greater. Spermatozoa washing is the most common method for the separation of spermatozoa from seminal plasma. Cryopreservation of human spermatozoa has become an important component of ARTs. Initial oocyte grading relies on direct optical analysis of oocyte–cumulus complex morphology. The grade is based on characteristics of the cumulus oophorus and corona radiata. Immature oocytes are defined as being at a stage of meiosis prior to metaphase of meiosis II. The extrusion of the first polar body marks the transition to a mature oocyte, which is now considered to be at meiosis II. The oocyte will remain at meiosis II until fertilization, when meiosis II resumes, the second polar body is extruded and the male and female pronuclei form. By injecting a spermatozoon into the oocyte cytoplasm, many steps of spermatozoa processing and developmental prerequisites are bypassed without compromising fertilization rates.
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Normal fertilization is characterized by the presence of two pronuclei, one male and one female, in the ooplasm and two polar bodies in the perivitelline space. Criteria for grading embryo quality include the rate of division as judged by numbers of blastomeres, size, shape, symmetry, appearance of the cytoplasm, and presence of cytoplasmic fragments. PGS consists of two steps, including micromanipulation and biopsy, and DNA analysis of gametes or embryos. For DNA analysis, there are two main techniques currently employed, PCR for single-gene disease detection and FISH for aneuploidy. Cryopreservation of gametes and embryos maximizes success of conception in any IVF cycle and prevents waste of specimens. Vitrification is a form of rapid cooling that utilizes very high concentrations of cryoprotectant that solidify without forming ice crystals.
ACKNOWLEDGMENTS The authors would like to thank Drs. Carrie Cosola-Smith, Thomas Pool, Timothy Schuster, and Theodore Thomas for critical review and constructive comments.
REFERENCES 1. Mortimer D, Templeton AA, Lenton EA, Coleman RA: Influence of abstinence and ejaculation-to-analysis delay on semen analysis parameters of suspected infertile men. Arch Androl 8:251–256, 1982. 2. Dickerman Z, Sagiv M, Savion M, et al: Andrological parameters in human semen of high (≥6ml) and low (≤1 ml) volume. Andropologia 21:353–362, 1989. 3. World Health Organization: The WHO Laboratory Manual for the Examination of Human Semen and Sperm–Cervical Mucus Interaction, 3rd ed., Cambridge, Cambridge University Press, 1992. 4. Lilja H, Oldbring J, Rannevik G, Laurell CB: Seminal-secreted proteins and their reactions during gelation and liquefaction of human semen. J Clin Invest 80:281–285, 1987. 5. Propping D, Tauber PF, Zaneveld, LJD, Schumacher GFB: Purification and characterization of two plasminogen activators from human seminal plasma. Fed Proc 33:289–293, 1974. 6. Keel BA, Webster BW: The Handbook of Laboratory Diagnosis and Treatment of Infertility. Boca Raton, Fla., CRC Press, 1990. 7. World Health Organization: The WHO Laboratory Manual for the Examination of Human Semen and Sperm–Cervical Mucus Interaction, 4th ed. Cambridge, Cambridge University Press, 1999. 8. Kruger TF, Menkveld R, Stander FS, et al: Sperm morphologic features as a prognostic factor in in vitro fertilization. Fertil Steril 46:1118–1123, 1986. 9. Jeyendran RS, Van der Van HH, Perez-Pelaez M, et al: Development of an assay to assess the functional integrity of the human spermatozoa membrane and its relationship to other semen characteristics. J Reprod Fertil 70:219–228, 1984. 10. Burkman LJ, Coddington CC, Fraken DR, et al: The hemizona assay (HZA): Development of a diagnostic test for the binding of human spermatozoa to the human hemizona pellucida to predict fertilization potential. Fertil Steril 49:688–697, 1988. 11. Yanagamachi R, Yanagamachi H, Rogers BJ: The use of zona-free animal ova as a test system for the assessment of fertilizing capacity of human spermatozoa. Biol Reprod 15:471–476, 1976.
12. Rogers BJ, Van Campen H, Ueno M, et al: Analysis of human spermatozoa fertilizing ability using zona-free ova. Fertil Steril 32:664–670, 1979. 13. Evenson DP, Jost LK, Baer RK, et al: Individuality of DNA denaturation patterns in human sperm as measured by the sperm chromatin structure assay. Reprod Toxicol 5:115–125, 1991. 14. Hayes WA (ed): Principles and Methods of Toxicology. New York, Raven Press, 1994. 15. Aitken RJ, Clarkson JS: Cellular basis of defective sperm function and its association with the genesis of reactive oxygen species by human spermatozoa. J Reprod Fertil 91:459–469, 1987. 16. Mahadevan M, Leeton JF, Trounson AO: Noninvasive method of semen collection for successful artificial insemination in a case of retrograde ejaculation. Fertil Steril 36:243–247, 1981. 17. Ohl DA, Menge AC, Sonksen J: Penile vibratory stimulation in spinal cord injured men: Optimized vibration parameters and prognostic factors. Arch Phys Med Rehabil 77:903–905, 1996. 18. Brindley GE: Electroejaculation: Its technique, neurological application implications and uses. J Neurol Neurosurg Psych 44:9–18, 1981. 19. Ohl DA, Bennett CJ, McCabe M: Predictors of success in electroejaculation of spinal cord injured men. J Urol 142:1483–1486, 1989. 20. Ohl DA, Menge AC, Jarow JP: Seminal vesicle aspiration in spinal cord injured men: Insight into poor sperm quality. J Urol 162:2048–2051, 1999. 21. Sheynkin YR, Ye Z, Menendez S, et al: Controlled comparison of percutaneous and microsurgical sperm retrieval in men with obstructive azoospermia. Hum Reprod 13:3086–3089, 1998. 22. Schlegel PN, Palermo GD, Goldstein M, et al: Testicular sperm extraction with intracytoplasmic sperm injection for nonobstructive azoospermia. Urol 49:435–440, 1997. 23. Schlegel PN: Testicular sperm extraction: Microdissection improves sperm yield with minimal tissue excision. Hum Reprod 14:131–135, 1999. 24. Manning M, Junemann KP, Alken P: Decrease in testosterone blood concentrations after testicular sperm extraction for intracytoplasmic sperm injection in azoospermic men. Lancet 352:37, 1988.
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Section 6 Infertility and Recurrent Pregnancy Loss 25. Zhu JJ, Tsirigotis M, Pelekanos M, Craft IL: In vitro maturation of human testicular spermatozoa. Hum Reprod 111:231–232, 1996. 26. Sherman JK: Freezing and freeze-drying of human spermatozoa. Fertil Steril 14:49–64, 1953. 27. Tournaye H, Merdad T, Silber S: No differences in outcome after intracytoplasmic sperm injection with fresh or with frozen–thawed epididymal spermatozoa. Hum Reprod 14:90–95, 1999. 28. Veeck LL, Wortham JW, Witmyer J, et al: Maturation and fertilization of morphologically immature human oocytes in a program of in vitro fertilization. Fert Steril 39:594–602, 1983. 29. Prins GS, Wagner C, Weidel L, et al: Gonadotropins augment maturation and fertilization of human immature oocytes cultured in vitro. Fertil Steril 47:1035–1037, 1987. 30. Nagy ZP, Cecile J, Liu J, et al: Pregnancy and birth after intracytoplasmic sperm injection of in vitro matured germinal-vesicle stage oocytes: Case report. Fertil Steril 65:1047–1050, 1996. 31. Chian RC, Buckett WM, Too LL, Tan SL: Pregnancies resulting from in vitro matured oocytes retrieved from patients with polycystic ovary syndrome after priming with human chorionic gonadotropin. Fertil Steril 72:639–642, 1999. 32. Chian RC, Buckett WM, Tulandi T, Tan SL: Prospective randomized study of human chorionic gonadotrophin priming before immature oocyte retrieval from unstimulated women with polycystic ovarian syndrome. Hum Reprod 15:165–170, 2000. 33. Cha KY, Koo JJ, Ko JJ, et al: Pregnancy after in vitro fertilization of human follicular oocytes collected from nonstimulated cycles, their culture in vitro and their transfer in a donor oocyte program. Fertil Steril 55:109–113, 1991. 34. Trounson A, Wood C, Kausche A: In vitro maturation and the fertilization and developmental competence of oocytes recovered from untreated polycystic ovarian patients. Fertil Steril 62:353–362, 1994. 35. Russell JB, Knezevich KM, Fabian KF, Dickson JA: Unstimulated immature oocyte retrieval: Early versus midfollicular endometrial priming. Fertil Steril 67:616–620, 1997. 36. Atiee SH, Pool TB, Martin JE: A simple approach to intracytoplasmatic sperm injection. Fertil Steril 63:652–655, 1995. 37. Gardner DK, Lane M: Blastocyst transfer. Clin Obstet Gynecol 46:231–238, 2003.
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38. Hogan B, Constantini F, Lacy E: Manipulating the mouse embryo: A laboratory manual. New York, Cold Spring Harbor Laboratory Press, 1986. 39. Yaron Y, Gamzu R, Malcov M: Genetic analysis of the embryo. In Gardner DK, Weissman A, Howles CM, Shoham Z (eds). Textbook of Assisted Reproductive Techniques: Laboratory and Clinical Perspectives. New York, Taylor & Francis, 2004, pp 319–332. 40. Wells D, Delhanty JD: Preimplantation genetic diagnosis: Applications for molecular medicine. Trends Mol Med 7:23–30, 2001. 41. Dyban A, Freidine M, Severova E, et al: Detection of aneuploidy in human oocytes and corresponding first polar bodies by FISH. J Assist Reprod Genet 13:73–78, 1996. 42. Verlinsky Y, Cieslak J, Lifches A, et al: Birth of healthy children following preimplantation diagnosis of common aneuploidies by polar FISH analysis. Fertil Steril 65:358–360, 1996. 43. Harper JC, Dawson K, Delhanty JDA, Winston RML: Use of fluorescent in situ hybridization (FISH) for the analysis of in vitro fertilization embryos: A diagnostic tool for the infertile couple. Hum Reprod 10:3255–3258, 1995. 44. Wilkinson DG: The theory and practice of in situ hybridization. In: Wilkinson DG (ed). In Situ Hybridization: A Practical Approach. New York, Oxford University Press, 1992, pp 1–13. 45. Verlinsky Y, Kuliev A: Preimplantation diagnosis of common aneuploidies in infertile couples of advanced maternal age. Hum Reprod 10:2076–2077, 1996. 46. The Ethics Committee of the American Fertility Society: Ethical considerations of assisted reproductive technologies. The cryopreservation of pre-embryos. Fertil Steril 62:56s–59s, 1994. 47. Porcu E: Oocyte cryopreservation. In Gardner DK, Weissman A, Howles CM, Shoham Z (eds). Textbook of Assisted Reproductive Techniques: Laboratory and Clinical Perspectives, 2nd ed. New York, Taylor & Francis, 2004, pp 233–242. 48. Rall W, Fahy G: Ice-free cryopreservation of mouse embryos at −196° C by vitrification. Nature 313:573–575, 1985. 49. Liebermann J, Tucker MJ, Graham JR, et al: Blastocyst development after vitrification of multipronuclear zygotes using flexipet denuding pipette. Reprod Biomed Online 4:146–150, 2002.
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Section 6 Infertility and Recurrent Pregnancy Loss Chapter
40
Complications of Assisted Reproductive Technologies James M. Goldfarb, Cynthia Austin, Nina Desai, Hanna Lisbona, and Barry Peskin
INTRODUCTION Since the birth of Louise Brown in 1978, over 1 million babies have been born as the result of assisted reproductive technology (ART) procedures. ART procedures are generally considered safe. But as with any medical procedure, there are potential complications. The goal remains to maximize the benefits while diminishing the risks. In this chapter, we discuss the two most important complications, ovarian hyperstimulation syndrome (OHSS) and multiple pregnancies. We review risks to the fetuses, including congenital malformations. Finally, we discuss the uncommon complications of the egg retrieval process and the question of fertility drugs and ovarian cancer.
OVARIAN HYPERSTIMULATION SYNDROME OHSS is the most common and potentially serious complication of ovarian hyperstimulation for ART procedures, especially in vitro fertilization (IVF). This syndrome consists of ovarian enlargement in conjunction with a continuum of symptoms, depending on severity (Fig. 40-1). In the mildest cases, the patient experiences only pelvic discomfort and nausea. More serious cases are associated with vomiting, abdominal distension, and ascites. The most severe cases can result in respiratory distress, oliguria, hemoconcentration, and thrombosis. In rare cases, death has been reported. Recognition of high-risk patients, judicious management of follicular stimulation, and aggressive management early in the course of the syndrome are necessary to minimize the incidence and severity of OHSS.
Incidence The vast majority of OHSS cases occur in association with ovarian stimulation with injectable gonadotropins. Only occasional cases have been observed after clomiphene citrate administration, and very rare cases have been reported during the first trimester of pregnancy resulting from spontaneous unstimulated ovulation.1,2 Sporadically reported cases of familial spontaneous OHSS may be due to a mutation in the follicle-stimulating hormone (FSH) receptor, leading to hypersensitivity of the corpus luteum to human chorionic gonadotropin (hCG).3,4 However, the great majority of cases develop after use of injectable gonadotropins for ovarian hyperstimulation before in vitro fertilization (IVF).
The actual frequency of OHSS varies depending on patient factors, surveillance methods, and management approaches. Mild cases occur in as many as 30% or more of patients undergoing controlled ovarian hyperstimulation with gonadotropins for IVF and often go unrecognized due to the benign nature of the signs and symptoms.5 In general, less than 5% of patients undergoing IVF would be expected to develop moderate symptoms and less than 1% will develop severe symptoms.6,7 It remains unclear why many high-risk induction cycles do not result in severe OHSS while others do.
Pathogenesis OHSS is the result of excessive follicular response during the follicular phase, but manifests exclusively during the luteal phase following a surge in luteinizing hormone (LH) or ovulatory dose of hCG. The severity and duration is intensified by additional doses of exogenous hCG for luteal support and rising levels of endogenous hCG if the patient becomes pregnant.1,5,8 Vasoactive Substances
OHSS is the result of amplification of normal ovulatory physiology. IVF stimulation protocols commonly result in maturation of upwards of 10 to 20 follicles of varying size on each ovary. OHSS is triggered by release of vasoactive substances in response to hCG or LH. These vasoactive substances cause increased capillary permeability, leading to third spacing of fluid, hemoconcentration, and reduced vascular volume. Possible participants in the pathogenesis of OHSS include vascular endothelial growth factor (VEGF), prostaglandins, other members of the cytokine family, and nitric oxide, as well as components of the renin and the angiotensin system, especially angiotensin II.9–13 All of these are recognized participants in the normal physiology of folliculogenesis and luteogenesis.14,15 The primary mediator of increased vascular permeability associated with OHSS appears to be the cytokine VEGF.9,10 VEGF is secreted by granulosa and theca cells in the late follicular phase. Neoangiogenesis, essential to folliculogenesis and especially to luteogenesis, is induced largely by VEGF.11–13 Ovarian hyperstimulation syndrome is most commonly thought to be the result of vascular hyperpermeability caused by excessive VEGF-induced changes associated with extreme neoangiogenesis. The expression of VEGF by granulosa cells has been shown to be up-regulated by hCG, and unbound levels of VEGF correlate with the severity of OHSS.16,17 Inhibition of VEGF is associated with improvement in vascular permeability.18,19 Evidence indicates
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Section 6 Infertility and Recurrent Pregnancy Loss Table 40-1 Risk Factors for Ovarian Hyperstimulation Syndrome (OHSS) Younger age Low body mass index Polycystic ovary syndrome Heightened response to stimulation Estradiol over 4000 pg/mL Large number of small and medium sized follicles hCG luteal phase supplementation Previous OHSS
A
increased sodium and water reabsorption in the proximal tubule and reduced exchange of hydrogen and potassium for sodium in the distal tubule, potentially leading to oliguria with prerenal azotemia, hyponatremia, and hyperkalemic acidosis.25 Medical complications secondary to OHSS include renal insufficiency, adult respiratory distress syndrome, hepatocellular damage, hypovolemic shock, disseminated intravascular coagulation, and thromboembolism.5
Risk Factors No single clinical characteristic or combination of characteristics is 100% predictive of OHSS. However, the incidence is increased by any factor that increases ovarian response (Table 40-1). Patients at highest risk for severe OHSS are those who meet the folowing criteria:
B Figure 40-1 A, Transvaginal ultrasonographic view of ovarian enlargement (cystic structure) with ascites in a patient with ovarian hyperstimulation syndrome (OHSS). Fluid clearly outlines the uterus. B, Transabdominal ultrasound scan showing fluid around the liver.
that supernumerary follicles are the predominant source of superphysiologic quantities of VEGF in patients who develop OHSS.20 VEGF acting directly or indirectly in concert with other factors may diffuse into the peritoneal cavity, resulting in increased permeability of diffuse mesothelial vessels. Removal of these substances by paracentesis may facilitate reduction of capillary hyperpermeability, resulting in the observed improvement in the clinical sequelae.21 Fluid Homeostasis
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The primary dysfunction in OHSS is movement of protein-rich fluid out of the vascular space into the abdominal cavity and occasionally the pleural or pericardial spaces, leading to varying degrees of hemoconcentration and hypovolemia. The hemoconcentration associated with OHSS leads to hypercoagulability and increased risk of thromboembolism, especially if it occurs in combination with thrombophilias or other coagulopathies.22,23 There is also evidence that OHSS may induce a primary hypercoagulable state independent of hemoconcentration.24 The hypovolemia resulting from OHSS can lead to low blood pressure and decreased central venous pressure, followed by decreased renal perfusion. Decreased renal perfusion results in
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peak estradiol levels in excess of 6000 pg/mL more than 30 follicles
For patients with both of these risk factors, the incidence of severe OHSS has been reported to be as high as 80%.26 The occurrence of OHSS is more closely correlated with degree of ovarian stimulation than it is with the dose and duration of gonadotropins.27–29 OHSS occurs more commonly in women with ovaries that are highly sensitive to FSH stimulation, specifically young women and women with polycystic ovary syndrome (PCOS).28,30 Higher doses of gonadotropin are also associated with an increased incidence of OHSS, but only to the extent that higher doses result in more vigorous ovarian stimulation.29 The presence of a large number of follicles, particularly small and moderate-sized follicles, at the time of initial hCG is a positive risk factor for OHSS.2 Estrogen produced by the developing follicles serves as a marker of the degree of ovarian hyperstimulation. High estrogen levels in excess of 4000 pg/mL are of particular concern in the presence of numerous small to medium-sized follicles in contrast to a smaller number of exclusively large or mature follicles.1,28,31
Clinical Symptoms Classification
OHSS is best thought of as a broad continuum of signs and symptoms.27,28 However, for management and reporting purposes, OHSS is generally classified as mild, moderate, or severe (Table 40-2). Mild OHSS is a self-limited and clinically benign condition characterized by ovarian enlargement (generally less than 5 cm), abdominal bloating, and discomfort. Moderate
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Chapter 40 Complications of Assisted Reproductive Technologies Table 40-2 Classification of Ovarian Hyperstimulation Syndrome Mild Ovarian enlargement (5 cm or less) Abdominal discomfort
Moderate Ovarian enlargement (6–10 cm) Nausea or gastrointestinal symptoms Abdominal discomfort Normal laboratory evaluation Mild ascites, not clinically evident
Severe Symptoms as above and other symptoms, such as respiratory distress Ovarian enlargement Severe ascites (clinically evident) Hydrothorax Elevated hematocrit (>45%) Elevated WBC count (>15,000/μL) Elevated creatinine Electrolyte abnormalities (hyponatremia, hyperkalemia) Elevated liver function tests
Critical (As a Subcategory of Severe) Severe end-organ dysfunction Oliguria, creatinine >1.6 mg/dL Severe respiratory distress Thrombotic complications Infection Severe hemoconcentration Hematocrit >55% WBC count >25,000/μL Modified from Navot D, Bergh PA, Laufer N: Ovarian hyperstimulation syndrome in novel reproductive technologies: Prevention and treatment. Fertil Steril 58:249–261, 1992.
OHSS indicates progressively greater ovarian enlargement and significant symptoms that are difficult to manage outside a hospital environment. Severe OHSS involves massive cystic ovarian enlargement in excess of 10 cm and tense abdominal ascites with or without pleural effusion.27 Onset of Symptoms
The LH surge or ovulatory hCG level is followed by formation of multiple corpus luteum cysts and unusually large, cystic ovaries. OHSS presents as early as several days after ovulation or egg retrieval or may not emerge until the last week of the cycle in response to the rising hCG resulting from embryo implantation. Most commonly, patients present with complaints of abdominal bloating, shortness of breath, nausea, unusual weight gain, and decreased urine output. Patients with severe OHSS appear ill, with marked abdominal distension secondary to ascites. They frequently become significantly short of breath in the supine position, again secondary to abdominal ascites. Laboratory findings include elevated hematocrit, leukocytosis, hyponatremia, hyperkalemia, elevated blood urea nitrogen (BUN)-to-creatinine ratio, and occasionally mildly elevated results on liver function tests. On ultrasound, ovaries will be large and cystic with variable amounts of free peritoneal fluid filling the abdominal space. Occasional patients will present with a pleural effusion, most commonly right sided, with or without abdominal ascites.29 Clinical Course
OHSS is self-limited. In the absence of pregnancy, it will resolve spontaneously with the onset of luteolysis at the end of the cycle. Resolution of OHSS is heralded by progressive resolution
of ascites and rapid diuresis. If the patient becomes pregnant, however, signs and symptoms will continue or even exacerbate during the second week after ovulation due to rising endogenous hCG levels. Continued observation and medical intervention is often necessary beyond the missed menstrual period. Despite continued rising hCG levels, however, the vast majority of cases will stabilize and begin to improve gradually before the 6-week ultrasound.
Prevention Avoidance of Excessive Stimulation
Although it is not possible to prevent all cases of hyperstimulation syndrome, recognition of high-risk patients followed by judicious management of gonadotropin therapy to avoid excessive stimulation can reduce the incidence of OHSS. Menotropin doses should be carefully considered for each patient based on her clinical characteristics. Lower doses and more frequent monitoring should be considered for those patients who are most likely to respond aggressively, especially young patients and those with PCOS. Frequent, sometimes daily, surveillance of serum estradiol levels and follicular growth can facilitate modulation of gonadotropin doses, limiting the rate of estrogen rise without a detrimental effect on follicular growth. If rapidly rising estrogen levels reach or threaten to become unacceptably high, withholding the daily dose of gonadotropin can reduce the incidence and severity of OHSS. This approach, coasting, can in some cases result in arrest and atresia of all or most of the follicles; however, in many cases hCG administration can be delayed until the estradiol level returns to a more acceptable level without a detrimental effect on the subsequent oocyte and embryo quality or pregnancy rate.33–36 Coasting has been shown to be associated with reduced concentrations of follicular VEGF and a significantly lower incidence of severe OHSS.37 Coasting is most successful when the serum estradiol has exceeded 3000 pg/mL and the lead follicle has reached a diameter larger than 14 mm. If growth of the lead follicles continues, administration of hCG can be withheld for up to 4 days until the serum estradiol reaches an acceptable level. Prolonged coasting beyond 4 days is associated with a decrease in implantation and pregnancy rates.38 Withholding hCG
Because the clinical signs and symptoms of hyperstimulation will not develop until final follicular maturation and luteinization occur in response to hCG or LH, it is most prudent to withhold the ovulatory dose of hCG in patients who are clearly overstimulated based on follicular number, size, and estrogen level.31,33 Although the decision to drop a cycle ultimately becomes a matter of clinical judgment, in general it is our practice to withhold hCG in the presence of a large number of small follicles and a peak estradiol level in excess of 4000 pg/mL. Intravenous Albumin
Intravenous administration of an osmotically active “colloid” agent at the time of retrieval appears to reduce the risk and severity of OHSS in high-risk patients. Administration of intravenous albumin (25 g) during and immediately after the egg retrieval has been recommended for women with a peak estradiol level of 3000 pg/mL or a large number of small and
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Section 6 Infertility and Recurrent Pregnancy Loss intermediate-sized follicles.39 Based on a meta-analysis using the Cochrane standard, it is estimated that for every 18 women treated with albumin, 1 case of OHSS will be avoided.40 However, prophylactic administration of albumin to high-risk patients remains controversial because of conflicting data regarding its efficacy as well as concerns regarding the expense and safety.41 The mechanism of action for intravenous albumin is not clear. It was initially hypothesized that albumin exerts it effect by increasing intravascular osmotic pressure. However, because of its small molecular weight, albumin is cleared from the circulation within a short time of the retrieval. Other possible mechanisms include increased plasma binding of a factor or factors involved in the pathogenesis of OHSS. Other osmotic agents have also been used with some success, including 5% hydroxyethylstarch and 3.5% degraded gelatin polypeptides (Haemaccel).42–44 Follicular Aspiration
Clinical experience suggests that follicular aspiration offers partial protection against hyperstimulation syndrome. Every effort should be made to empty as many follicles as possible at the time of retrieval. Luteal Phase Support
OHSS is promoted by luteogenesis and inhibited by luteolysis. Strategies to limit the severity and longevity of OHSS are based on limiting luteogenesis or promoting luteolysis. Luteal support with hCG should not be used in patients with a peak estradiol level greater than 3000 pg/mL because hCG increases the duration and severity of OHSS by promoting luteogenesis. Progesterone with or without additional estrogen is the safer alternative. Introduction of a GnRH antagonist early in the luteal phase will lead to early luteolysis.45 Because OHSS resolves with involution of the corpora lutea, the clinical course of severe OHSS can be abbreviated or even eliminated by this approach. If the stimulation protocol did not include down-regulation with a GnRH agonist, the gonadotropin flare secondary to initiation of a GnRH agonist can be used to induce oocyte maturation and ovulation followed almost immediately by irreversible luteolysis.18,46–51 Pituitary response to initiation of a GnRH agonist is preserved following a GnRH antagonist/gonadotropin stimulation protocol. If embryos are transferred in a cycle in which premature luteolysis is induced, exogenous hormone replacement is required to support endometrial maturation and implantation.52 Alternatively, the embryos can be cryopreserved for transfer at a later time.53
Management of OHSS Diagnosis
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Proactive management of patients with early signs and symptoms of OHSS can ameliorate the severity of OHSS.54 Patients generally present with complaints of abdominal bloating, shortness of breath, and nausea. Symptomatic patients should be seen and evaluated promptly. Clinical parameters should include a physical examination, including a chest and abdominal examination (but not a bimanual pelvic examination) as well as a pelvic or abdominal ultrasound for ovarian enlargement or ascitic fluid and to rule out torsion.
Table 40-3 Complications Associated with OHSS Ascites Pulmonary Hydrothorax Adult respiratory distress syndrome Pulmonary embolism Pulmonary edema Atelectasis Hemorrhage Thrombosis Venous (majority) Upper limb, head and neck veins Arterial Intracerebral Sepsis Liver dysfunction Renal failure Ovarian cysts Adnexal torsion Cyst rupture Cyst hemorrhage
Table 40-4 General Principles of Management of a Hospitalized Patient with OHSS Daily physical examination, avoiding a pelvic examination Monitor vital signs, including oxygen saturation (pulse oximeter) Monitor urine output closely Daily checks of weight and abdominal girths Daily hematocrit/hemoglobin, white blood cell count, liver enzymes, serum electrolytes, blood urea nitrogen, and creatinine testing Aggressive intravenous normal saline or colloids to maintain adequate urine output and to treat the hemoconcentration Subcutaneous prophylactic anticoagulation Paracentesis or thoracocentesis, if necessary Adapted from Avecillas JF, Falcone T, Arroliga AC: Ovarian hyperstimulation syndrome. Criti Care Clin 20:679–695, 2004.
Laboratory studies should include complete blood count, electrolytes, BUN, and creatinine. Hemoconcentration (hematocrit >45%) heralds the development of ascites, marginal renal perfusion, and decreasing urine output and increases the risk of thromboembolic events.55 Most patients with OHSS will have some degree of ascites (Table 40-3). Less commonly, patients will develop pleural effusion, which can occur unilaterally (usually on the right) and in the absence of significant abdominal ascites. A high index of suspicion and careful evaluation are important to differentiate this condition from pulmonary embolism.32 Treatment
Active management of OHSS early in the onset of the signs and symptoms of the syndrome can avoid hospitalization and minimize the progression and complications of OHSS.54 Patients at risk should be instructed to monitor fluid intake, urine output, and daily weights (Table 40-4). Oral fluid replacement is encouraged with electrolyte-containing liquids such as sports drinks.
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Chapter 40 Complications of Assisted Reproductive Technologies Intravenous fluid and electrolyte management can often be managed in the outpatient setting. Patients presenting with evidence of hemoconcentration manifested by rising hematocrit well above baseline, particularly approaching 50%, with leukocytosis, hyponatremia, hypokalemia, or reduced urine output require intravenous fluid replacement with crystalloid.8 Abdominal paracentesis can be safely performed under ultrasound guidance either abdominally or transvaginally in patients with significant ascites.55 Patients presenting with significant hemoconcentration but without significant ascites should be monitored closely for accumulation of extravascular fluid after hydration. Paracentesis is expected to significantly improve urine output and hemoconcentration, possibly by reducing intraabdominal pressure compressing the vena cava.8,56,57 Osmotically active volume expanders, most commonly albumin, used in combination with intravenous crystalloids and paracentesis, can also be used reduce hemoconcentration and maintain vascular volume.43,54,58 Anticoagulants should be considered if hemoconcentration does not respond to IV fluids and volume expanders or if the patient has a concomitant hypercoagulability, such as Factor V Leiden deficiency. Hospitalization is necessary for any patient who cannot be comfortably managed as an outpatient or who develops significant medical complications.59 Rare complications of severe OHSS include vascular collapse, adult respiratory distress syndrome, renal failure, and venous thrombosis. For the patient with the most extreme presentation of severe OHSS, adequate support may require in addition to the above, placement of a central line and administration of pressors (see Table 40-3). As a last resort for management of these extreme cases, surgical destruction of the corpora lutea or pregnancy termination has been advocated.60 With aggressive proactive and active management of high-risk patients, these measures should have a very limited place in clinical management of OHSS.6 However, surgical intervention may be required for ovarian cysts associated with OHSS if they undergo torsion, hemorrhage, or rupture.
Figure 40-2 Multiple gestations associated with assisted reproductive technology (ART) procedures. A transvaginal ultrasonographic view of three intrauterine gestational sacs.
Some couples believe that, because they have never been able to get pregnant at all, they do not need to be worried about multiple pregnancies. Similarly, patients who failed to get pregnant with the transfer of two embryos in a first IVF cycle feel uncomfortable unless they transfer more embryos in a subsequent IVF cycle. These understandable emotional issues, in combination with the overwhelming financial investment required by IVF, result in a higher than necessary multiple pregnancy rate in the United States. Further exacerbating this trend is the pressure on IVF programs to report high success rates to stay competitive. Although there is an increasing emphasis on the undesirability of multiple pregnancies with IVF, success of IVF programs still is undoubtedly judged predominantly by the “take home baby rate,” which does not take into consideration the significant financial costs and morbidity of multiple pregnancies (Fig. 40-2).
MULTIPLE PREGNANCIES
Scope of the Problem of Multiple Pregnancies with ART
Multiple pregnancies are the most common and serious ART complication. The significant stress of not being able to get pregnant can, not infrequently, make both infertile couples and healthcare providers forget the obvious—the goal of ART is not merely getting pregnant but having healthy children. Many couples do not appear to be appropriately concerned regarding multiple pregnancies, either as a result of the intense desire to achieve pregnancy or the lack of knowledge regarding the morbidity associated with multiple pregnancies. A survey of 77 women embarking on either gonadotropin or IVF therapy showed that 95% of women preferred getting pregnant with triplets to not getting pregnant and 68% of women preferred getting pregnant with quadruplets to not getting pregnant.61 Another report on patient preference showed that more than 20% of women embarking on infertility treatment preferred multiple pregnancies to a singleton pregnancy.62 Very significantly, 4% of those favoring multiple pregnancies ranked quadruplets as their most desired outcome. Based on these observations, it is not surprising that couples undergoing IVF are often very aggressive regarding the number of embryos to transfer.
The number of multiple pregnancies in the United States has increased greatly since 1980. Although a small part of the increase in multiple pregnancy rates is due to other factors, such as increased maternal age, the vast portion is due to infertility treatments. From 1980 to 1999, the multiple pregnancy rates increased approximately 60%, from 1.9% to 3.1% of all births. Numerically most of these represented twin pregnancies. However, the risk of higher-order pregnancies increased from 37 to 193 per 100,000 births, or by more than 400%.63 The impact of fertility treatments, and particularly ART, on higher-order pregnancies is momentous. Although ART is responsible for only 0.4% of all live births, this technology is responsible for 13.9% of twin births and 41.8% of higher-order deliveries (Table 40-5).64 Higher-order multiples are associated with a large number of medical problems.65–70 The application of ART treatments appears to increase the risk of both dizygotic and monozygotic twins and of higher-order deliveries. Ovulation induction increases the incidence of monozygotic twinning to 1.2% compared to the 0.4% incidence in the general population.71,72 IVF increases the risk of monozygotic
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Section 6 Infertility and Recurrent Pregnancy Loss Table 40-5 Effect of Assisted Reproductive Technology (ART) on Total Births by Plurality—United States 2001 Contribution of ART to Total Births in the United States (%)
Number of ART Infants*† (% of total)
Number of Total U.S. Infants§ (% of total)
Live births in single deliveries
17,123 (46.2%)
3,897,216 (96.8%)
0.4
Live births in multiple deliveries
19,964 (53.8%)
128,717 (3.2%)
15.5
Twin deliveries
16,838 (45.4%)
121,246 (3.0%)
13.9
3,126 (8.4%)
7,471 (0.2%)
41.8
Triplets or higher order deliveries Total number of live births
37,087
4,025,933
0.9
*Source: Assisted Reproductive Technology Surveillance System. † Includes infants conceived from ART procedures performed in 2000 and born in 2001 and infants conceived from ART procedures performed in 2001 and born in 2001. § Source: U.S. natality file, CDC, National Center for Health Statistics.
twinning even further, especially when embryos are transferred at the blastocyst stage. Monozygotic twinning occurs in 5.6% of IVF pregnancies conceived after blastocyst transfer compared to 2% after cleavage-stage transfer.74 In addition, the presence of more than one gestational sac also increases the risk of monozygotic twinning.75–77
Problems Associated with Multiple Pregnancies Prematurity
Clearly, the major cause of morbidity with multiple pregnancies is prematurity. Fully one third of triplets and two thirds of quadruplets will be born at less (and often considerably less) than 32 weeks’ gestation.66 Approximately 25% of twins and 75% of triplets will be admitted to a neonatal intensive care unit (NICU). The average number of days these infants will spend in a NICU is 18 days for twins, 30 days for triplets, and 58 days for quadruplets.67 Small for Gestational Age
In addition to prematurity, multiple gestations are also at increased risk for small for gestational age (SGA) babies, the rate of which increases with gestational age. For twins, 28% will be SGA by 34 weeks’ gestation, and this rate will climb to 40% by 37 weeks’ gestation.67 For triplets, 50% will be SGA by 35 weeks’ gestation.
severe handicaps are increased by 30%.70 In triplets overall handicaps are increased by 97% and severe handicaps are increased by 71%. Birth defects are increased by multiple gestations. Monozygotic twins are twice as likely as dizygotic twins to be born with congenital malformations. In one study, the risk of significant congenital anomalies among triples was 5%.69 Infant Mortality
Infant mortality is greatly increased by multiple gestations. The perinatal mortality rate for triplets, including all intrauterine demises and deliveries occurring after 20 weeks’ gestation, is greater than 10% in many studies.69 The intrauterine fetal demise risk for multiple gestations is increased for several reasons. In addition to deaths caused by congenital anomalies and the risk associated with SGA, infants are at increased risk of oligohydramnios, cord accidents, and twin-to-twin transfusion syndrome. Neonatal death rates are increased, primarily as a result of prematurity. The most common deadly associated condition is respiratory distress syndrome, which accounts for half of neonatal deaths resulting from premature birth. Infant deaths (under age 1 year) are not as commonly discussed as a sequelae of multiple gestations. Using U.S. vital statistics, it has been shown that, compared to singletons, the number of infant deaths for twins are increased sixfold and for triplets 17-fold.70 Maternal Complications
Essentially all maternal complications of pregnancy are increased by the occurrence of multiple gestations. In addition to preterm labor, this includes preterm premature rupture of membranes, preeclampsia, gestational diabetes, anemia, postpartum hemorrhage, and even the relatively rare acute fatty liver of pregnancy.69 Financial Costs
The financial costs of multiple pregnancies are also tremendous. An evaluation of births at a Boston hospital from 1986 to 1991 found that added costs of multiple pregnancies were approximately $38,000 and $110,000 for twins and higher-order multiple pregnancies, respectively.77 Goldfarb and colleagues78 estimated the added cost (above normal costs for a singleton delivery) per woman delivered of pregnancies from an IVF program during the years 1991 and 1992. Estimated added costs included the cost of the IVF procedure, admissions for premature labor, time off from work, and costs for ongoing care of premature infants. The authors found that the added cost per delivery of IVF patients was approximately $39,000 for singleton and twin deliveries versus approximately $343,000 for triplet and quadruplet pregnancies.
Cerebral Palsy and Other Handicaps
602
Of all the sequelae of multiple gestations, cerebral palsy is perhaps the most disturbing. Apparently as a result of both prematurity and SGA, the rate of cerebral palsy for twins is increased 5.5-fold, and for triplets the risk is increased almost 20-fold.68,69 Other handicaps are also clearly increased by multiple gestations. In twins, overall handicaps are increased by 39% and
Parenting Issues
The psychological impact of raising infants born of multiple gestations cannot be underappreciated. An evaluation of parents of IVF twins reported that these couples found parenting to not be as satisfying as they expected.79 Furthermore, parents of IVF twins seem to be more stressed than parents of naturally conceived twins.
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Chapter 40 Complications of Assisted Reproductive Technologies Steps to Minimize the Problem of ART-Associated Multiple Pregnancies Number of Embryos to Transfer after IVF
Legislation in some European countries strictly limits embryo transfers to two embryos for most patients. In the United States, embryo transfer policy remains controversial because of the issues of parents’ rights to decide on the number of embryos and tradeoffs between higher pregnancy rates and higher multiple pregnancy rates. The American Society for Reproductive Medicine (ASRM) has established guidelines for the number of embryos to transfer in an IVF cycle, the most recent of which was published in 2004.80 These guidelines recommend the transfer of two embryos for patients under age 35 in the absence of “extraordinary circumstances.” Many are strongly advocating stricter guidelines because of the feeling that the goal of ART should only be a healthy singleton birth.81 For many patients, very good success rates can be achieved by transferring a single embryo at the blastocyst stage.82 In view of this, the 2004 ASRM guidelines state that “for patients with the most favorable prognosis, consideration should be given to transferring only a single embryo.”80 Of course, transfer of a single embryo, particularly at the blastocyst stage, does not eliminate the risk of multiple pregnancies. Insurance coverage appears to influence the number of embryos transferred. A lower incidence of transfer of three or more embryos was found in insured versus noninsured states.83 However, the overall effect of insurance coverage on multiple pregnancies was modest. It has been hypothesized that a substantial effect on multiple pregnancies will occur only if insurance coverage is combined with mandated limits on the number of embryos transferred after IVF.84 Another way to decrease the risks of multiple pregnancies is to revise the way in which IVF program success is assessed. In the United States, the “take home baby rate” is the standard by which an IVF program is judged, and the multiple pregnancy rate is relatively rarely examined. Embryo implantation rate, a very good indicator of the quality of an IVF program has been incorporated into the Society for Assisted Reproductive Technology (SART) reporting process. Clearly there is no simple answer to the problem of ART and multiple pregnancies; effort on many fronts is necessary. It would seem that a combination of insurance coverage with a reasonable limitation in the number of embryos transferred combined with a SART reporting system that emphasizes implantation rates would be very helpful. Also, very importantly, educating our patients as to the risks of multiple pregnancies is imperative. Our ultimate goal should not be to get patients pregnant, but rather to help them build a healthy family.
NEONATAL RISKS NOT RELATED TO MULTIPLE BIRTHS Singleton births after IVF, compared to naturally conceived singletons, have an increased risk of congenital anomalies, intrauterine growth restriction, and preterm delivery. In several studies, the risk of major congenital anomalies was increased in singletons. It is uncertain whether this is due to the IVF techniques or the underlying infertility problem. A meta-analysis showed pooled odds ratio of 1.31 (95% CI, 1.17–1.45).85 This
implies a 30% to 40% increase in risk of congenital anomalies. Because the overall risk of congenital anomalies is 1% to 3%, this suggests an increased risk after IVF of 1.3% to 3.9%. Intracytoplasmic sperm injection (ICSI) may be associated with a higher risk of sex and autosomal chromosomal anomalies.86
COMPLICATIONS OF TRANSVAGINAL ULTRASOUND-DIRECTED FOLLICULAR ASPIRATION Ultrasound-guided transvaginal aspiration of follicles for the recovery of oocytes is the method of choice in IVF programs. Complications from such procedures are rare, making it difficult to assess their true incidence. Some of those complications can be severe and life threatening; therefore, one has to be aware of their occurrence with the aim of accurate diagnosis and prompt intervention. The major groups of complications are hemorrhage from the vaginal wall, the ovary, or other pelvic vessels; pelvic infection; and trauma to related pelvic structures, such as bowel or ureters.
Bleeding It is not unusual to observe bleeding from the vaginal vault puncture site at routine inspection at the end of the oocyte retrieval. Vaginal hemorrhage occurs in 8.6% of cases (229 out of 2670 patients).87 Vaginal hemorrhage with a loss of more than 100 mL of blood occurs in 0.8%. This usually responds to the application of firm pressure for a few minutes with no adverse postoperative sequelae. Severe intra-abdominal bleeding is reported in less than 0.1% of cases.88 Hemorrhage significant enough to cause hemoperitoneum can result from follicle puncture, from the ovarian vessels, or from a punctured iliac vessel. Massive retroperitoneal hematoma requiring an emergency laparotomy can occur from bleeding from the sacral vein.
Pelvic Infections Vaginal retrieval carries a risk of pelvic infection of less than 1%. Infections can take the form of postoperative pelvic infections or pelvic abscesses that can require surgical drainage in some cases.87,88 The time from oocyte retrieval to the manifestation of a pelvic abscess can be relatively long. Although the diagnosis will be made within 3 weeks after oocyte retrieval in most cases, an interval of 56 days has been reported.87 There has been a report of a rupture of bilateral ovarian abscesses occurring at the end of the second trimester in a twin pregnancy achieved after oocyte retrieval for IVF.89 The cause of pelvic infection after oocyte retrieval is believed to be direct inoculation of vaginal microorganisms. Anaerobic opportunists of the vagina are found to be etiologic agents in pelvic abscesses after transvaginal oocyte retrieval, including Escherichia coli, Bacteroides fragilis, Enterococcus, and Peptococcus.87,88 Prophylactic antibiotics should be considered before oocyte retrieval, especially in high-risk patients, such as those with a history of salpingitis, endometriosis, pelvic adhesions, hydrosalpinx, or pelvic surgery. Although there is currently no consensus as to the best antibiotics to use, an animal study suggested that ampicillin or doxycycline might be superior to cefazolin.91
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Section 6 Infertility and Recurrent Pregnancy Loss Vaginal disinfection with a 1% solution of povidone-iodine seems attractive, but a study showed that the pregnancy rate was significantly lower in the group after disinfection by povidoneiodine compared to the normal saline washing group.91
Other Complications Other potentially life-threatening complications are extremely rare after ultrasound-directed ovum retrieval. There has been a report of a bilateral infection of endometriotic cysts after oocyte aspiration and another of acute abdomen due to accidental puncture of a dermoid cyst during oocyte aspiration.92,93 It may be wise to avoid aspiration of sono-opaque cysts during oocyte retrieval. If sebaceous material is unexpectedly obtained during retrieval, copious rinsing of the presumed dermoid cyst might decrease the risk of postaspiration peritonitis from leaking material. One case of vertebral osteomyelitis caused by E. coli was reported.94 The patient presented with severe low back pain 1 week after ovum retrieval. Other potential complications are trauma to related pelvic structures, including bowel, ureters, and bladder.
apparently due to the close ultrasound monitoring used.105,106 A meta-analysis of 10 studies suggested that women with infertility are more likely to develop ovarian cancer whether they used fertility drugs or not.107 This might suggest that underlying defects that result in infertility might also increase ovarian cancer risk. Fortunately, the weight of evidence strongly indicates that there is no causal link between fertility drugs and ovarian cancer. Based on this information, the Practice Committee of the ASRM recommends that infertility patients be counseled that no causal relationship has been established between ovulationinducing drugs and ovarian cancer.108
PEARLS ●
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Ovarian Cancer and Fertility Drugs: A False Alarm? Ovarian cancer is diagnosed in approximately 24,000 women in the United States every year. The association of infertility, use of infertility drugs, and ovarian cancer has generated much debate.95-109 Although it is not the most common gynecologic malignancy, it is the most deadly, and approximately half of women with ovarian cancer will die of their disease.110 It is believed that limiting the number of ovulatory cycles decreases the risk of ovarian cancer, because multiparity and long-term use of oral contraceptives decrease this risk. Based on this known association, it was hypothesized that the converse might also be true: inducing multiple ovulations with fertility drugs might increase ovarian cancer risk.98 Several small, retrospective studies in the early 1990s appeared to show an association between fertility drugs and ovarian cancer.95,99–101 A study by Whittemore generated much interest and concern when it suggested that fertility drug use might be associated with a 2.8 relative risk of ovarian cancer.95,97 Several larger studies and meta-analyses were subsequently published that were unable to find an increased risk of ovarian cancer associated with fertility drug use.103–108 More than one of these studies reported the diagnosis of an unusual number of ovarian cancers within the first year after starting IVF,
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The vast majority of OHSS cases occur in association with ovarian stimulation with injectable gonadotropins. Sporadically reported cases of familial spontaneous OHSS may be due to a mutation in the FSH receptor, leading to hypersensitivity of the corpus luteum to hCG. OHSS is triggered by release of vasoactive substances in response to hCG or LH. The primary dysfunction in OHSS is movement of proteinrich fluid out of the vascular space into the abdominal or other cavities, leading to varying degrees of hemoconcentration and hypovolemia. Patients at highest risk for severe OHSS are those with peak estradiol levels in excess of 6000 pg/mL or more than 30 follicles. Luteal support with hCG should not be used in patients with a peak estradiol level greater than 3000 pg/mL; progesterone is a safer alternative. Patients with OHSS generally present with complaints of abdominal bloating, shortness of breath, or nausea. Active management of OHSS is essentially fluid and electrolyte driven. Although a small part of the increase in multiple pregnancy rates is due to other factors, such as increased maternal age, the vast portion is due to infertility treatments. The ASRM has issued guidelines to decrease the incidence of multiple births. These guidelines recommend the transfer of two embryos for patients under age 35 in the absence of “extraordinary circumstances.” The major groups of complications are hemorrhage from the vaginal wall, the ovary, or other pelvic vessels; pelvic infection; and trauma to related pelvic structures such as bowel or ureters.
REFERENCES
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5. Schenker JG, Weinstein D: Ovarian hyperstimulation syndrome: A current survey. Fertil Steril 30:255, 1978. 6. Navot D, Bergh PG, Laufer N: Ovarian hyperstimulation syndrome in novel reproductive technologies: Prevention and treatment. Fertil Steril 58:249, 1992. 7. Hugues JN: Ovarian stimulation for assisted reproductive technologies. In Vayena E, Rowe PJ, Griffin PD (eds) Current Practices and Controversies in Assisted Reproduction. Geneva, World Health Organization, 2002.
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31. Haning RV, Austin CW, Carlson H, et al: Plasma estradiol is superior to ultrasound and urinary estradiol glucuronide as a predictor of ovarian hyperstimulation during induction of ovulation with menotropins. Fertil Steril 40:31, 1983. 32. Roden S, Juvin K, Homasson JP, et al: An uncommon etiology of isolated pleural effusion: The ovarian hyperstimulation syndrome. Chest 118:256, 2000. 33. Benadiva CA, David O, Kligman I, et al: Withhold gonadotropins administration is an effective alternative for prevention of ovarian hyperstimulation syndrome. Fertil Steril 67:724, 1997. 34. Dhont M, Van der Straeten F, DeSutter P: Prevention of severe ovarian hyperstimulation by coasting. Fertil Steril 70:847, 1998. 35. Sher G, Salem R, Feinman M, et al: Eliminating the risk of lifeendangering complication following overstimulation with menotropin fertility agents: A report on women undergoing in vitro fertilization and embryo transfer. Obstet Gynecol 81:1009, 1993. 36. Sher G, Zouves C, Feinman M, et al: “Prolonged coasting”: An effective method for preventing severe ovarian hyperstimulation syndrome in patients undergoing in vitro fertilization. Hum Reprod 10:3107, 1995. 37. Tozer AJ, Iles RK, Iammarrone E, et al: The effects of “coasting” on follicular fluid concentrations of vascular endothelial growth factor in women at risk of developing ovarian hyperstimulation syndrome. Hum Reprod 19:522, 2004. 38. Levinsohn-Tavor O, Friedler S, Schachter M, et al: Coasting—what is the best formula? Hum Reprod 18:937, 2003. 39. Shalev E, Giladi Y, Matilsky M, et al: Decreased incidence of severe ovarian hyperstimulation syndrome in high risk in vitro fertilization patients receiving intravenous albumin: A prospective study. Hum Reprod 10:1373, 1995. 40. Aboulghar M, Evers JH, Al-Inany H: Intravenous albumin for preventing severe ovarian hyperstimulation syndrome: A Cochrane review. Hum Reprod 17:3027, 2002. 41. Belliver J, Munoz EA, Soares SR, et al: Intravenous albumin does not prevent moderate-severe hyperstimulation syndrome in high-risk IVF patients: A randomized study. Hum Reprod 18:2283, 2003. 42. Graf MA, Fischer R, Naether OG, et al: Reduced incidence of ovarian hyperstimulation syndrome by prophylactic infusion of hydroxyethyl starch solution in an in vitro fertilization programme. Hum Reprod 12:2599, 1997. 43. Gamzu R, Almog B, Levin Y, et al: Efficacy of hydroxyethyl starch and Haemaccel for the treatment of severe ovarian hyperstimulation syndrome. Fertil Steril 77:1302, 2002. 44. Rabinerson D, Ben Rafael Z, Keslin J, et al: 10% hydroxyethyl starch for plasma expansion in the treatment of severe ovarian hyperstimulation syndrome: A case report. J Reprod Med 46:68, 2001. 45. de Jong D, Macklon NS, Mannaerts BM, et al: High dose gonadotrophinreleasing hormone antagonist (ganirelix) may prevent ovarian hyperstimulation syndrome caused by ovarian stimulation for in vitro fertilization. Hum Reprod 13:573, 1998. 46. Imoedemhe DAG, Chan RCW, Sigue AB, et al: A new approach to the management of patients at risk of ovarian hyperstimulation in an in vitro fertilization. Hum Reprod 6:1088, 1991. 47. Itskovitz J, Boldes R, Barlev A, et al: The induction of LH surge and oocyte maturation by GnRH analogue (buserelin) in women undergoing ovarian stimulation for in vitro fertilization. Gynecol Endocrinol 2:165, 1988. 48. Itskovitz-Eldor J, Kor S, Mannaerts B: Use of a single bolus of GnRH agonist triptorelin to trigger ovulation after GnRH antagonist ganirelix treatment in women undergoing ovarian stimulation for assisted reproduction, with special reference to the prevention of ovarian hyperstimulation syndrome: Preliminary report: Short communication. Hum Reprod 15:1965, 2000. 49. Lanzone A, Fulghesu AM, Villa P, et al: Gonadotropin-releasing hormone agonist versus human chorionic gonadotropin as a trigger of ovulation in polycystic ovarian disease gonadotropin hyperstimulated cycles. Fertil Steril 62:35, 1994. 50. Lewit N, Kol S, Manor D, et al: The use of GnRH analogs for induction of the preovulatory gonadotropin surge in assisted
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reproduction and prevention of the ovarian hyperstimulation syndrome. Gynecol Endocrinol 4:13, 1995. Lewit N, Kol S, Manor D, et al: Comparison of GnRH analogs and hCG for the induction of ovulation and prevention of ovarian hyperstimulation syndrome (OHSS): A case-control study. Hum Reprod 11:1399, 1996. Kol S: Luteolysis induced by a gonadotropin-releasing hormone agonist is the key to prevention of ovarian hyperstimulation syndrome. Fertil Steril 81:1, 2004. Tummon IS, Contag SA, Thornhill AR, et al: Cumulative first live birth after elective cryopreservation of all embryos due to ovarian hyperresponsiveness. Fertil Steril 81:309, 2004. Olivennes F, Fanchin R, Bouchard P, et al: Triggering of ovulation by a gonadotropin-releasing hormone (GnRH) agonist in patients pretreated with a GnRH antagonist. Fertil Steril 66:151, 1996. Fluker M, Copeland J, Yuzpe AA: An ounce of prevention: Outpatient management of the ovarian hyperstimulation syndrome. Fertil Steril 73:821, 2000. Aboulghar M, Mansour R, Serour G, et al: Ultrasonically guided vaginal aspiration of ascites in the treatment of severe ovarian hyperstimulation syndrome. Fertil Steril 53:933, 1990. Levin I, Amog B, Avni A, et al: Effect of paracentesis of ascitic fluid on urinary output and blood indices in patients with severe ovarian hyperstimulation syndrome. Fertil Steril 77:986, 2002. Padilla S, Zamaria S, Baramki T, et al: Abdominal paracentesis for the ovarian hyperstimulation syndrome with severe pulmonary compromise. Fertil Steril 53:365, 1990. Aboulghar MA, Mansour RT, Serour GI, et al: Management of severe hyperstimulation syndrome by ascitic fluid aspiration and intensive intravenous fluid therapy. Obstet Gynecol 81:18, 1993. Avecillas JF, Falcone T, Arroliga AC: Ovarian hyperstimulation syndrome. Crit Care Clin 20:679–695, 2004. Amarin ZO: Bilateral partial oophorectomy in the management of severe ovarian hyperstimulation syndrome. Hum Reprod 18:659, 2003. Goldfarb J, Kinzer DJ, Boyle M, et al: Attitudes of in vitro fertilization and intrauterine insemination couples toward multiple gestation pregnancy and multifetal pregnancy reduction. Fertil Steril 65:815, 1996. Ryan GL, Zhang SH, Dokras A, et al: The desire of infertile patients for multiple births. Fertil Steril 81:500, 2004. Mathews TJ, MacDorman MF, Menacker F: Infant mortality statistics from the 1999 period linked birth/infant death data set. Nat Vital Stat Rep 50:11, 2002. Norwitz ER. Multiple pregnancy: Trends past, present and future. Infertil Reprod Med Clin North Am 9:351, 1998. Martin JA, Hamilton BE, Venture SJ, et al: Births: Final data for 2001. Nat Vital Stat Rep 51:104, 2002. Newman RB, Luke B: Neonatal and post-neonatal considerations. In RB Newman, B Luke (eds). Multifetal Pregnancy. Philadelphia, Lippincott Williams & Wilkins, 2000, p 243. Alexander G, Kogan M, Martin J: What are the fetal growth patterns of singletons, twins and triplets in the USA? Clin Obstet Gynecol 41:115, 1998. Pharoah PO, Cooke T: Cerebral palsy and multiple births. Arch Dis Child Fetal Neonatal Ed 75:174, 1996. Devine PC, Malone FD, Athanassiou A, et al: Maternal and neonatal outcome of 100 consecutive triplet pregnancies. Am J Perinatol 18:225–235, 2001. Luke B, Keith LG: The contribution of singletons, twins and triplets to low birth weight, infant mortality and handicap in the United States. J Reprod Med 37:661, 1992. Derom C, Vlietinck R, Derom R, et al: Increased monozygotic twinning rate after ovulation induction. Lancet 1:1236, 1987. Bulmer MG: The Biology of Twinning in Man. Oxford, Clarendon Press, 1970. Milki AA, Jun SH, Hinckley MD, et al: Incidence of monozygotic twinning with blastocyst transfer compared to cleavage-stage transfer. Fertil Steril 79:503, 2003.
74. Wenstrom KD, Syrop CH, Hammit DG, et al: Increased risk of monochorionic twinning associated with assisted reproduction. Fertil Steril 60:510, 1993. 75. Machin G, Bamforth F, Innes M, et al: Some perinatal characteristics of monozygotic twins who are dichorionic. Am J Med Genet 55:71, 1995. 76. Su LL: Monoamniotic twins: Diagnosis and management. Acta Obstet Gynecol Scand 81:995, 2002. 77. Callahan TL, Hall JE, Ettner SL, et al: The economic impact of multiple-gestation pregnancies and the contribution of assistedreproduction techniques to their incidence. NEJM 339:573, 1998. 78. Goldfarb JM, Austin C, Lisbona H, et al: Cost-effectiveness of in vitro fertilization. Obstet Gynecol 87:18, 1996. 79. Cook R, Bradley S, Golombok S: A preliminary study of parental stress and child behaviour in families with twins conceived by in vitro fertilization. Hum Reprod 13:3244, 1998. 80. The Practice Committee of the Society for Assisted Reproductive Technology and the American Society for Reproductive Medicine: Guidelines on number of embryos transferred. Fertil Steril 82:773, 2004. 81. Healy D: Damaged babies from assisted reproductive technologies: Focus on the BESST (birth emphasizing a successful singleton at term) outcome. Fertil Steril 81:512, 2004. 82. Gardner DK, Surrey E, Minjarez D, et al: Single blastocyst transfer: A prospective randomized trial. Fertil Steril 81:551, 2004. 83. Reynolds MA, Schieve LA, Jeng G, et al: Does insurance coverage decrease the risk for multiple births associated with assisted reproductive technology? Fertil Steril 80:16, 2003. 84. Reynolds MA, Schieve LA, Peterson HB: Insurance is not a magic bullet for the multiple birth problem associated with assisted reproductive technology. Fertil Steril 80:32, 2003. 85. Hansen M, Bower C, Milne E et al: Assisted reproductive technologies and the risk of birth defects—a systematic review. Hum Reprod 20:328, 2005. 86. Van Steirteghem A, Bonduelle M, Devroey P, et al: Follow up of children born after ICSI. Hum Reprod Update 8:111, 2002. 87. Bennett SJ, Waterstone JJ, Cheng WC, et al: Complications of transvaginal ultrasound-directed follicle aspiration: A review of 2670 consecutive procedures. J Assist Reprod Genet 10:72, 1993. 88. Govaerts I, Devreler F, Delbaere A, et al: Short-term medical complications of 1500 oocyte retrievals for in vitro fertilization and embryo transfer. Eur J Obstet Gynecol Reprod Biol 77:239, 1998. 89. den Boon J, Kimmel CEJM, Nagel TC, et al: Pelvic abscess in the second half of pregnancy after oocyte retrieval for in vitro fertilization: Case report. Hum Reprod 14:2402, 1999. 90. Chetkowski RJ, Nass TE: Anesthesia and antibiotics in assisted reproduction. Assist Reprod Rev 2:36, 1992. 91. Van Os HC, Roozenburg BJ, Jansen-Caspers HAB, et al: Vaginal disinfection with povidone-iodine and the outcome of in vitro fertilization. Hum Reprod 7:349, 1992. 92. Yaron Y, Peyser MR, Samuel D, et al: Infected endometriotic cysts secondary to oocyte aspiration for in vitro fertilization. Hum Reprod 9:1759, 1994. 93. Coccia ME, Becattini C, Bracco GL, et al: Acute abdomen following dermoid cyst rupture during transvaginal ultrasonographically guided retrieval of oocytes. Hum Reprod 11:1897, 1996. 94. Almog B, Rimon E, Yovel I, et al: Vertebral osteomyelitis: A rare complication of transvaginal ultrasound-guided oocyte retrieval. Fertil Steril 73:1250, 2000. 95. Whittemore AS, Harris R, Itnyre J, et al: Characteristics relating to ovarian cancer risk: collaborative analysis of 12 US case-control studies. Am J Epidemiol 136:1184, 1992. 96. Cohen J, Forman R, Harlap S, et al: IFFS expert group report on the Whittemore study related to the risk of ovarian cancer associated with the use of infertility agents. Hum Reprod 8:966, 1993. 97. Fischel S, Jackson P: Follicular stimulation for high tech pregnancies: Are we playing it safe? BMJ 299:309, 1989. 98. Heintz APM, Hacker NF, Lagasse LD: Epidemiology and etiology of ovarian cancer: A review. Obstet Gynecol 66:127, 1985.
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Chapter 40 Complications of Assisted Reproductive Technologies 99. Goldberg GL, Runowicz CD: Ovarian carcinoma of low malignant potential, infertility, and induction of ovulation—is there a link? Am J Obstet Gynecol 166:853, 1992. 100. Rossing MA, Daling JR, Weiss NS, et al: Ovarian tumors in a cohort of infertile women. NEJM 331:771, 1994. 101. Priore GD, Robischon K, Phipps WR. Risk of ovarian cancer after treatment for infertility. NEJM 332:1300, 1995. 102. Potashnik G, Lerner-Geva L, Genkin L, et al: Fertility drugs and the risk of breast and ovarian cancers: Results of a long-term follow-up study. Fertil Steril 71:853, 1999. 103. Mosgaard BJ, Lidegaard O, Kjaer SK, et al: Infertility, fertility drugs, and invasive ovarian cancer: A case-control study. Fertil Steril 67:1005, 1997. 104. Dor J, Lerner-Geva L, Rabinovici J, et al: Cancer incidence in a cohort of infertile women who underwent in vitro fertilization. Fertil Steril 77:324, 2002.
105. Venn A, Watson L, Bruinsma F, et al: Risk of cancer after use of fertility drugs with in vitro fertilization. Lancet 354:1586, 1999. 106. Doyle P, Maconochie N, Beral V, et al: Cancer incidence following treatment for infertility at a clinic in the UK. Hum Reprod 17:2209, 2002. 107. Kashyap S, Moher D, Fung Kee Fung M, et al: Assisted reproductive technology and the incidence of ovarian cancer: A meta-analysis. Obstet Gynecol 103:785, 2004. 108. Practice Committee of the American Society of Reproductive Medicine. Fertility drugs and the risk of ovarian cancer. Nov. 2003. Accessible at www.asrm.org 109. Cancer Statistics 2001. CA Cancer J Clin 51:15, 2001.
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Section 6 Infertility and Recurrent Pregnancy Loss Chapter
41
Recurrent Pregnancy Loss Anne S. Devi Wold, Aydin Arici, and William H. Kutteh
INTRODUCTION
RECURRENCE RISK
Recurrent pregnancy loss is a profound personal tragedy to couples seeking parenthood and a formidable clinical challenge to their physicians. Spontaneous abortion occurs in approximately 15% of clinically diagnosed pregnancies in reproductive-age women, but recurrent pregnancy loss occurs in about 1% to 2% of this same population.1 Great strides have been made in characterizing the incidence and diversity of this heterogeneous disorder, and a definite cause of pregnancy loss can be established in approximately two thirds of couples after a thorough evaluation.2 A complete evaluation will include investigations into genetic, endocrinologic, anatomic, immunologic, microbiologic, thrombophilic, and iatrogenic causes. Recurrent pregnancy losses may induce significant emotional distress; in some cases intensive supportive care may be necessary. Successful outcomes will occur in more than two thirds of all couples.3
The main concerns of couples who have had a spontaneous abortion are the cause and the risk of recurrence. In a first pregnancy, the overall risk of loss of a clinically recognized pregnancy is 15%.5,6 The true rate of early pregnancy loss, however, is estimated to be around 50% because of the high rate of losses that occur before the first missed menstrual period. Studies that evaluated the frequency of pregnancy loss, based on highly sensitive tests for quantitative hCG, indicated that the total clinical and preclinical losses in women age 20 to 30 is approximately 25%, whereas the loss rate in women age 40 or more is at least double that figure.7,8 For women who have had one miscarriage, the risk of another loss rises slightly, to 14% to 21%. After two or three miscarriages the rate rises to 24% to 29% and 31% to 33%, respectively.9 The ability to predict the risk of recurrence is influenced by several factors.
DEFINITION OF PREGNANCY LOSS
Maternal Age
The traditional definition of recurrent pregnancy loss included those couples with three or more spontaneous, consecutive pregnancy losses. Ectopic and molar pregnancies are not typically included. There is no specific classification for those women who have multiple spontaneous miscarriages interspersed with normal pregnancies, nor is it clear whether occult early miscarriages diagnosed by sensitive human chorionic gonadotropin (hCG) assays should be included in these definitions. Several studies have recently indicated that the risk of recurrent miscarriage after two successive losses is similar to the risk of miscarriage in women after three successive losses; thus, it is reasonable to start an evaluation after two or more consecutive spontaneous miscarriages to determine the etiology of their pregnancy loss, especially when the woman is older than age 35 or when the couple has had difficulty conceiving.3,4 Any loss before 20 gestational weeks is considered a miscarriage. Some authors further divide these into embryonic losses, which occur before the ninth gestational week, and fetal losses, which occur at any time from the 9th gestational week to 20 weeks’ gestation, although there is no developmental phase to justify this distinction. Those couples with primary recurrent loss have never had a previous viable infant; those with secondary recurrent loss have previously delivered a pregnancy beyond 20 weeks’ gestation and then suffered subsequent losses. Other investigators advocate the designation of tertiary recurrent loss to identify those women who have multiple miscarriages interspersed with normal pregnancies.
Advancing maternal age is associated with a higher rate of pregnancy loss of both normal and abnormal conceptuses.10,11 This probably reflects poor oocyte quality and reduced endocrine function in this group. In one study of more than 1 million pregnancies, the overall rate of spontaneous abortion was 11% and the approximate rates of clinically recognized miscarriage according to maternal age were 9% to 17% (age 20 to 30), 20% (age 35), 40% (age 40), and 80% (age 45).10
The Cause of Pregnancy Loss The specific cause of pregnancy loss affects future outcomes. For example, carriers of balanced translocations 13:14 have a 25% risk of spontaneous abortion. The carriers of 21:22 translocation almost invariably miscarry. Women with submucosal leiomyomas have a 70% chance of recurrent loss if uncorrected.
Pregnancy Outcome Although the risk of miscarriage increases with each successive pregnancy loss, a pregnancy ending in a live birth reduces the risk of miscarriage in the subsequent gestation.12,13
Parity Increasing parity is associated with an increased rate of spontaneous abortion.14 This may be partially explained by the correlation between maternal age and parity.
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Section 6 Infertility and Recurrent Pregnancy Loss Gestational Age The gestational age at the time of pregnancy loss should be considered in determining both the etiology of the loss and risk of recurrence. The recurrence risk increases as gestational age at the time of loss increases.11,15
History of Oligomenorrhea In one study, a menstrual cycle longer than 34 days was the most important predictor for a pregnancy loss.13
ETIOLOGIES OF RECURRENT PREGNANCY LOSS Genetic Factors Single gene, chromosomal, X-linked, or multifactorial disorders can result in sporadic or recurrent pregnancy loss. Chromosomal Disorders
Parental chromosome anomalies occur in 3% to 5% of couples with recurrent pregnancy loss as opposed to 0.2% in the general population. These include translocations, inversions, and the relatively rare ring chromosomes. Balanced translocations are the most common chromosomal abnormalities contributing to recurrent pregnancy loss.16 In recurrent pregnancy loss, this abnormality is found more frequently in the female partner, at a female-to-male ratio of from 2:1 up to 3:1. Translocations
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In translocations, chromosome segments are exchanged between nonhomologous chromosomes. There are two main types of translocation: reciprocal and Robertsonian. In reciprocal translocations, the type of rearrangement results from breakage of nonhomologous chromosomes, with reciprocal exchange of the broken-off segments. Usually only two chromosomes are involved, and because the exchange is reciprocal, the total chromosome number is unchanged. Reciprocal translocations are relatively common and are found in approximately 1 in 500 newborns. Like other balanced structural rearrangements, they are associated with a high risk of unbalanced gametes and abnormal progeny. Robertsonian translocations involve two acrocentric chromosomes (numbers 13, 14, 15, 21, or 22) that fuse near the centromere region with loss of the short arms. Although a carrier of a Robertsonian translocation is phenotypically normal, there is a risk of unbalanced gametes and therefore unbalanced offspring. The risk of subsequent abortions varies with the type of translocation and the sex of the carrier. Robertsonian translocations are a more homogeneous group, and so the information on them is the most consistent. Studies indicate that when the Robertsonian translocation is maternal, there is a greater risk that the fetus will exhibit an unbalanced phenotype.17 Neri and coworkers found that carriers of these translocations had a 20% to 25% risk of spontaneous abortion. The only exceptions are translocations involving homologous chromosomes. If, for example, both copies of chromosome 22 fuse, the carrier should produce only trisomy 22 or monosomy 22, all of which would abort. Carriers of this type of translocation should therefore have a 100% rate of pregnancy loss, but two unexplained normal offspring from such carriers have been reported.18,19
Inversions
Chromosomal inversions occur less frequently than translocations. An inversion occurs when a single chromosome undergoes two breaks and is reconstituted, with the segment between the breaks inverted. Inversions are of two types: paracentric, in which both breaks occur in one arm, and pericentric, in which there is a break in each arm. An inversion does not usually cause an abnormal phenotype in carriers, because it is a balanced rearrangement. Its medical significance is for the progeny; a carrier of either type of inversion is at risk of producing abnormal gametes that may lead to pregnancy loss. A female inversion carrier is at an approximately 8% risk of producing anomalous offspring; the risk is reduced to 4% in male carriers.20 Ring Chromosomes
Ring chromosomes are formed when a chromosome undergoes two breaks and the broken ends of the chromosome reunite in a ring structure. Ring chromosomes are quite rare; because of mitotic instability, it is not uncommon for ring chromosomes to be found in only a proportion of cells. The medical literature is limited to isolated case reports, and the specifics of the effects of ring chromosomes on recurrent pregnancy loss are not known.21 Recurrent Aneuploidy
The first chromosomally abnormal abortus was documented in 1961, and since then a large body of data on the chromosomal status of spontaneous abortuses has accumulated. The overall frequency of chromosome abnormalities in spontaneous abortions is at least 50%. Of these abnormalities, most are numerical: 52% are trisomies, 29% are monosomy 45,X, 16% are triploidies, 6% are tetraploidies, and 4% are structural rearrangements.22 The earlier the abortion, the higher the chance of chromosomal abnormality. In Boúe’s study,22 66% of abortions at 2 to 7 weeks’ gestation were abnormal, whereas the percentage fell to 23% for abortions at 8 to 12 weeks’ gestation. Evidence suggests that some couples are at risk for conceptions complicated by recurrent aneuploidy. Empirically, the birth of a trisomic infant places a woman at an approximate 1% increased risk for a subsequent trisomic conceptus.23 Germline mosaicism has been reported in recurrent cases of Down syndrome and may also be responsible for recurrent aneuploidy in some couples.24 Single-Gene Mutations
The role of single-gene mutations at the molecular level in recurrent pregnancy loss remains speculative. It is known from studies in transgenic mice that some selected mutations and inactivation of some specific transcription factors can cause pregnancy failure.25 It is speculated that similar mutations in genes required for embryonic, placental, or cardiac development in humans are likely to cause pregnancy loss. X-Inactivation
In somatic cells of female mammals, only one X chromosome is active. Inactivation of the second X occurs early in embryonic life to achieve dosage compensation with males. The inactive X may be paternal or maternal; it is entirely a matter of chance which of the pair becomes inactivated in a cell. Occasionally, preferential inactivation of one allele occurs. Extremely skewed X-inactivation, defined as more than 90% inactivation of one
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Chapter 41 Recurrent Pregnancy Loss allele, is observed in 2% of newborns and 4.5% of reproductiveage women.26 Several authors have found the skewed X-inactivation pattern in phenotypically normal women with recurrent pregnancy loss.27,28 Others have also found a statistically significant increase in the spontaneous abortion rate among family members who carried the skewed X trait.29 Presumably these women have an X-linked mutation or germline mosaicism.
Endocrinologic Factors Endocrine factors may contribute to 8% to 12% of recurrent pregnancy loss. Progesterone is essential for successful implantation and maintenance of pregnancy. Therefore, disorders related to impaired progesterone production or actions are likely to affect pregnancy success. These include luteal phase insufficiency, hyperprolactinemia, and polycystic ovary syndrome (PCOS). Other endocrinologic factors associated with increased risk of pregnancy loss include diabetes, thyroid disease, and decreased ovarian reserve.
or greater in the midluteal phase of the menstrual cycle are generally utilized to exclude luteal phase defect. Untreated Hypothyroidism
Untreated hypothyroidism may increase the risk of miscarriage. A recent study of more than 700 patients with recurrent pregnancy loss identified 7.6% with hypothyroidism.35 Hypothyroidism is easily diagnosed with a sensitive thyrotropin test, and patients should be treated to become euthyroid before attempting a next pregnancy. It has also been suggested that thyroid antibodies are elevated in women with recurrent pregnancy loss. A retrospective study of 700 patients with recurrent pregnancy loss demonstrated that 158 women had antithyroid antibodies but only 23 of those women had clinical hypothyroidism on the basis of an abnormal thyrotropin value.36 The presence of antithyroid antibodies may imply abnormal T-cell function; therefore, an immune dysfunction rather than an endocrine disorder may be responsible for the pregnancy losses. Insulin Resistance
Luteal Phase Defect
Maintenance of early pregnancy depends on the production of progesterone by the corpus luteum. Between 7 and 9 weeks’ gestation the developing placenta takes over progesterone production. Luteal phase defect is defined as an inability of the corpus luteum to secrete progesterone in high enough amounts or for too short a duration. Abnormalities of the luteal phase have been reported to occur in up to 35% of women with recurrent abortion.30 Several potential mechanisms are thought to give rise to a luteal phase defect: decreased production of progesterone by the corpus luteum, decreased follicle-stimulating hormone (FSH) levels in the follicular phase, abnormal patterns of luteinizing hormone (LH) secretion, decreased response by the endometrium to already-secreted progesterone, and increased prolactin levels. The preponderance of evidence suggests that luteal phase defect is a preovulatory event most likely linked to an alteration in preovulatory estrogen stimulation, which may indicate poor oocyte quality and a poorly functioning corpus luteum.31,32 Classically, the diagnosis is based on results of endometrial biopsy. The endometrium is considered out of phase when the histologic dating lags behind the menstrual dating by 2 days or more. However, there is considerable interobserver and intraobserver variation in the interpretation of the biopsies. Furthermore, the expression of a luteal phase defect is not consistent in affected women, and unaffected women frequently have endometrial histology suggestive of luteal phase defect. Because of these issues, luteal phase defect is diagnosed only when two consecutive biopsies are out of phase. Endometrial biopsy is performed 10 days after the LH surge or after cycle day 24 of an idealized 28-day cycle. Some authors have advocated the measurement of serum progesterone levels in the luteal phase for the diagnosis of luteal phase defect, with levels below 10 ng/mL considered abnormal.33 However, progesterone levels are subject to large fluctuations because of pulsatile release of LH. Moreover, there is a lack of correlation between serum levels of progesterone and endometrial histology.34 Nonetheless, serum progesterone levels of 10 ng/mL
Patients with poorly controlled diabetes are known to have an increased risk of spontaneous miscarriage, which is reduced to normal spontaneous loss rates when women are euglycemic preconceptually.37 Hyperglycemia and vascular complications resulting in compromised blood flow to the uterus may be responsible for the pregnancy loss. It is known that women with PCOS have an increased risk of miscarriage. The mechanism is unknown, but may be related to elevated serum LH levels and high testosterone and androstenedione concentrations, which may adversely affect the endometrium.38 It also may be related to the high prevalence of insulin resistance in these women.39 Testing for fasting insulin and glucose is simple, and treatment with insulin-sensitizing agents may reduce the risk of recurrent miscarriage.40 Elevated Day 3 FSH
Elevated day 3 FSH levels have been associated with decreased pregnancy rates in women undergoing in vitro fertilization (IVF). Although the frequency of elevated day 3 FSH levels in women with recurrent miscarriage is similar to the frequency in the infertile population, the prognosis for recurrent miscarriage is increased with increased day 3 FSH levels.41 Thus, it is speculated that women with recurrent pregnancy loss and elevated day 3 FSH levels may have poor quality oocytes with inherent chromosomal abnormalities. Although no treatment is available, testing should be performed in women over age 35 with recurrent pregnancy loss, and appropriate counseling should follow. Hyperprolactinemia
Normal circulating levels of prolactin may play an important role in maintaining early pregnancy. Data from animal studies suggest that elevated prolactin levels may adversely affect corpus luteal function; however, this concept has not been proven in humans.42 A recent study of 64 hyperprolactinemic women showed that bromocriptine therapy was associated with a higher rate of successful pregnancy and that prolactin levels were significantly higher in women who miscarried.43
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Section 6 Infertility and Recurrent Pregnancy Loss Anatomic Factors Anatomic uterine defects are present in 15% to 20% of women evaluated for three or more consecutive spontaneous abortions.2 These anatomic abnormalities can be classified as congenital or acquired. Uterine malformations appear to predispose women to reproductive difficulties, including first- and second-trimester fetal losses, preterm labor, and abnormal fetal presentation. Congenital Uterine Anomalies
Congenital malformations of the reproductive tract result from failure to complete bilateral duct elongation, fusion, canalization, or septal resorption of the müllerian ducts. Müllerian anomalies were found in 8% to 10% of women with three or more consecutive spontaneous abortions who underwent hysterosalpingography or hysteroscopic examination of their uteri.2,44 Inadequate vascularity, compromising the developing placenta, and reduced intraluminal volume have been theorized as possible mechanisms leading to pregnancy loss. The most common abnormality associated with pregnancy loss is the septate uterus. The spontaneous abortion rate is high, averaging about 65% of pregnancies in some studies.45 A septum is primarily composed of fibromuscular tissue that is poorly vascularized (Fig. 41-1). This lack of vascularization may compromise decidual and placental growth. Alternatively, a uterine septum may impair fetal growth as a result of reduced endometrial capacity or a distorted endometrial cavity.45 Uncontrolled studies suggest that women who undergo resection of the uterine septum have higher delivery rates than women without treatment. Other congenital abnormalities, such as uterus didelphys, bicornuate uterus, and unicornuate uterus, are more frequently associated with later trimester losses or preterm delivery. Diethylstilbestrol Exposure
Diethylstilbestrol (DES) is an orally active synthetic estrogen that was introduced in the 1940s for the treatment of recurrent pregnancy loss, premature delivery, and other complications of pregnancy. The use of DES in pregnancy was banned in 1971.46 Uterine abnormalities occur in 69% of women exposed to DES in utero.46 The most common abnormality is a T-shaped
uterine cavity (70%). Other abnormalities include a small uterus, constriction rings, and intrauterine filling defects. In addition, 44% of DES-exposed women have structural changes in the cervix, including an anterior cervical ridge, cervical collar, hypoplastic cervix, and pseudopolyp. Women with a history of in utero exposure to DES appear to have a greater risk of adverse pregnancy outcome, including a twofold increased risk of spontaneous abortion and a ninefold increase in ectopic pregnancy rates.47 Acquired Uterine Abnormalities Intrauterine Adhesions
Intrauterine trauma resulting from vigorous endometrial curettage or postabortion endometritis is a common instigator for the development of adhesions. Intrauterine adhesions (synechiae) are an acquired uterine defect that has been associated with recurrent miscarriage. The severity of adhesions may range from minimal to complete ablation of the endometrial cavity. The term Asherman’s syndrome is often used to describe intrauterine adhesions associated with amenorrhea. These adhesions are thought to interfere with normal placentation and are treated with hysteroscopic resection. Intrauterine Masses
Intrauterine cavity abnormalities, such as leiomyomas and polyps, can contribute to pregnancy loss. There are several hypotheses concerning how leiomyomas may be associated with recurrent pregnancy loss. Depending on the leiomyoma size and location, it may partially obliterate or alter the contour of the intrauterine cavity, providing a poorly vascularized endometrium for implantation or otherwise compromising placental development. Uterine leiomyomas and polyps may also act like an intrauterine device (IUD), causing subacute endometritis. Until recently, it was felt that only submucous leiomyomas should be surgically removed before subsequent attempts at pregnancy. However, several recent studies investigating the implantation rate in women undergoing IVF have clearly demonstrated decreased implantation with intramural leiomyomas in the range of 30 mm.48 When smaller leiomyomas are identified, it is unclear if myomectomy is beneficial.49 Incompetent Cervix
Cervical incompetence can be considered an acquired uterine anomaly that is associated with recurrent pregnancy loss. The diagnosis of cervical incompetence is based on the presence of painless cervical dilation resulting in the inability of the uterine cervix to retain a pregnancy. Cervical incompetence commonly causes pregnancy loss in the second trimester. It may be associated with congenital uterine abnormalities, such as septate or bicornuate uterus. Rarely, it may be congenital following in utero exposure to DES.47 It has been reported that trauma to the cervix from conization, loop electrosurgical excision procedures, dilation of the cervix during pregnancy termination, or short cervical lengths on ultrasound increase the risk of cervical incompetence.50
IMMUNOLOGIC FACTORS
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Figure 41-1 Hysteroscopic septum division with scissors. Notice the avascular tissue of the septum.
The primary function of the immune system is to recognize and eliminate potentially pathogenic organisms from the body. To understand how immunologic factors can affect pregnancy, a
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Chapter 41 Recurrent Pregnancy Loss basic understanding of the normal immune response is required. The immune response has two components: the innate, or nonspecific, immune response and the acquired, or adaptive, immune response.
Innate and Acquired Immune Responses The innate immune response provides a rapid but relatively weak and nonspecific response. This represents the body’s first line of defense against pathogenic invasion. It is mediated by nonspecific soluble products (lysozyme, complement, and acute phase proteins) as well as host defense cells such as macrophages and natural killer (NK) cells. NK cells are large granular lymphocytes that are not of T-cell or B-cell lineage. The function of NK cells is direct killing of virus-infected cells and production of cytokines, resulting in a rapid but relatively nonspecific response to infection. They may also be important in polarizing T cells toward Th-1 responses via production of interferon-γ (IFN-γ). Acquired or adaptive immune responses are antigen-specific and lead to memory, but require 4 to 7 days to be effectively generated. T cells and B cells and a small proportion of NK cells largely mediate these responses. B cells differentiate in bone marrow. T and B cells occur in tissues in approximately equal numbers. T cells are responsible for cell-mediated immunity and are essential for B-cell function.51
Human Leukocyte Antigens T cells recognize processed antigenic peptides presented in association with cell-surface molecules called human leukocyte antigens (HLA), which are products of a group of genes in the major histocompatibility complex (MHC), located on chromosome 6 in humans. HLA molecules are cell-surface glycoproteins that are present on the surface of nearly every cell in the human body and are important in the defense against intracellular pathogens, such as viral infection and oncogenic transformation. They constitute the tissue type of an individual. T cells originate from the bone marrow and migrate to the thymus, where they mature. During this process only T cells that have a low binding affinity to HLA and self-peptides are allowed to mature into CD4+ and CD8+ T cells. In summary, only T cells that can recognize nonself but will not react to self are chosen. T cells recognize antigens via the T-cell receptor on the surface.
T-helper Lymphocytes T cells produce a range of cytokines following an immune challenge. The type of cytokine determines their differentiation into T helper 1 (Th1) and T helper 2 (Th2) lymphocytes. For example, Th1 lymphocytes secrete interleukin-2 (IL-2) and IFN-γ, creating a pro-inflammatory environment. Conversely, Th2 lymphocytes secrete cytokines, such as IL-4 and IL-10, that are predominantly involved in antibody production following an antigenic challenge. The actions of the two types of lymphocytes are intertwined, acting in concert and responding to counterregulatory effects of their cytokines. Hormones have a powerful effect on this action. During their reproductive years, women are more likely to develop a Th1 response after challenge with an infectious agent or antigen, except during pregnancy, when a Th2 environment prevails.52
Autoimmune Factors: Maternal Response to Self In some instances, there is a failure in normal control mechanisms that prevents an immune reaction against self, resulting in an autoimmune response.53 Autoantibodies to phospholipids, thyroid antigens, nuclear antigens, and others have been investigated as possible causes for pregnancy loss.35 Antiphospholipid antibodies include both the lupus anticoagulant and anticardiolipin antibodies. There is still controversy concerning testing for other phospholipids, but an increasing number of studies suggest that antibodies to phosphatidyl serine are also associated with pregnancy loss.54 Systemic Lupus Erythematosus
Most clinical studies find that pregnancy loss is more common among women with systemic lupus erythematosus (SLE) than among normal women.55 The rate of spontaneous abortions among patients with SLE in one large study was estimated at 21%.56 Nearly three quarters of pregnancy losses appear to occur in the second and third trimesters.57 Most fetal deaths in women with SLE are associated with the presence of antiphospholipid antibodies.55,58 In a study of women with SLE and recurrent pregnancy loss, women with antiphospholipid antibodies had a tenfold increased risk of miscarriage compared to women with SLE but without antiphospholipid antibodies.55 Other factors associated with pregnancy loss in this population include (1) disease activity before conception, (2) the onset of SLE during pregnancy, and (3) underlying renal disease. Women with active SLE should be advised to delay conception until remission is established. Women with moderate renal insufficiency should be advised against pregnancy. Women should also be counseled about the higher rates of preeclampsia and premature delivery with SLE.57 Antiphospholipid Antibody Syndrome
Antiphospholipid antibody syndrome is an autoimmune condition characterized by the production of moderate to high levels of antiphospolipid antibodies and certain clinical features. The presence of antiphospholipid antibodies (anticardioplipin and lupus anticoagulant) during pregnancy is a major risk factor for adverse pregnancy outcome.59 In a large meta-analysis of studies of couples with recurrent abortion, the incidence of antiphospholipid antibody syndrome was between 15% and 20%, compared to about 5% in nonpregnant women without a history of obstetric complications.60 It is not yet understood how antiphospholipid antibodies arise in patients with the syndrome. Genetic factors and infection may play a role. The antibodies generated in patients with antiphospholipid antibody syndrome appear to recognize epitopes on phospholipid-binding proteins, unlike the antibodies that arise following infections such as syphilis and Lyme disease, which recognize phospholipids directly.61 Several mechanisms have been proposed by which antiphospholipid antibodies might mediate pregnancy loss. It appears that different coagulation proteins may be involved in binding to phospholipids, which may explain the predisposition to thrombosis. Antibodies against phospholipids could increase thromboxane and decrease prostacyclin synthesis within placental vessels. The resultant prothrombotic environment could promote vascular constriction, platelet adhesion, and placental
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Section 6 Infertility and Recurrent Pregnancy Loss infarction.60 Antiphospholipid antibodies appear to interfere with various components of the protein C antithrombotic pathway, including inhibiting the formation of thrombin, decreasing protein C activation by the thrombomodulin–thrombin complex, inhibiting assembly of protein C complex, inhibiting activated protein C activity, and binding to factors Va and VIIIa in ways that protect them from proteolysis by activated protein C.61 Another proposed mechanism is the disruption of the placental antithrombotic molecule, annexin V. The levels of annexin V are reduced in placental villi of women with recurrent pregnancy loss who are antiphospholipid antibody-positive.62 Antiphospholipid antibodies can also recognize heparin and heparinoid molecules and thereby inhibit antithrombin III activity.63 Antiphospholipid antibodies can interact with cultured human vascular endothelial cells with resultant injury or activation.61 A more direct action on the trophoblastic cells has been demonstrated and explains how antiphospholipid antibodies can cause early fetal loss. Antiphospholipid antibodies have been demonstrated to inhibit secretion of human placental chorionic gonadotropin and to inhibit the expression of trophoblast cell adhesion molecules (α1 and α5 integrins, E- and VE-cadherins).64 Antithyroid Antibodies
An increased frequency of antithyroid antibodies (antithyroid peroxidase, antithyroglobulin) have been reported in women with recurrent pregnancy loss. However, if the patient is euthyroid, the presence of antithyroid antibodies does not affect pregnancy outcome.65 Women who have positive antithyroid antibodies and are euthyroid are at an increased risk for hypothyroidism during and after pregnancy. These women should have their thyrotropin level tested during each trimester and postpartum for thyroiditis.66 Antinuclear Antibodies
Approximately 10% to 15% of all women will have detectable antinuclear antibodies regardless of their history of pregnancy loss. Their chance of successful pregnancy outcome is not dependent on the presence or absence of antinuclear antibodies. Treatments such as steroids have been shown to increase the maternal and fetal complications without benefiting live births67; thus, routine testing and treatment for antinuclear antibodies is not indicated. Alloimmune Factors: Maternal Immune Response to Trophoblast
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Implantation is the process by which the embryo is intimately connected with the maternal uterine and blood-borne cells. The implanting embryo possesses paternal antigens and therefore may be rejected as an allograft. However, in most cases, fetal rejection by the maternal immune system does not occur and seems to be prevented by mechanisms not yet defined. Alloimmune factors have been suggested to be associated with recurrent pregnancy loss. HLA sharing was thought to be associated with recurrent pregnancy loss based on a decreased maternal immune response and, thus, decreased production of blocking antibodies. Recent large studies, however, reveal no association between HLA (and HLA-DQα) homozygosity, and recurrent pregnancy loss.68 Other investigators have implicated certain embryotoxic factors, such as tumor necrosis factor (TNF-α) and IFN-δ, identified in the supernatants of peripheral
blood lymphocytes from women with pregnancy loss; however, this has not been confirmed by independent studies. Immunophenotypes of endometrial cells from women with recurrent pregnancy loss demonstrate altered NK cell (CD56+) populations. Some have suggested that increased NK cells are associated with pregnancy loss, whereas others have indicated that decreased NK cells are associated with pregnancy loss. None of these findings have been clearly associated with pregnancy loss; thus, there are no definite recommended tests at this time.69 Several theories have been proposed to account for the immuneprivileged state of the decidua. Mechanical Barrier Effect of the Trophoblast
The pregnant uterus was proposed to have a mechanical barrier formed by the trophoblast and the decidua, which prevented the movement of activated T cells from the periphery to the implantation site. Similarly, this barrier would isolate the fetus and prevent the escape of fetal cells into the maternal circulation. However, several studies have shown that traffic exists in both directions across the maternal–fetal interface. Systemic Immunosuppression
Some studies have suggested that pregnancy-associated plasma protein A, human placental lactogen, human placental protein 14, and progesterone may have immune-depressant activity in lymphocytes.52 Lack of Expression of Human Leukocyte Antigens
This theory is based on the fact that unlike every other cell in the human body, the trophoblast cells do not express class I MHC antigens HLA-A and HLA-B. The cytotrophoblast cells of the placenta that invade the uterine decidua express HLA-C, HLA-E, and HLA-G antigens, and the villous trophoblasts, which are in contact with the maternal intervillous surface and maternal blood, are class I MHC negative. The apparent lack of MHC gene expression suggests that the embryo may be protected from direct immunologic attack by the MHC-restricted T cells. However, because the NK cells of the innate immune system recognize and kill cells that do not express MHC, the trophoblast and the embryo could be vulnerable to those NK cells that are pervasive at sites of implantation. The expression of HLA-C, HLA-E, and HLA-G by trophoblast cells may protect against NK cell-mediated killing as well as modulate cytokine expression profiles at the maternal–fetal interface.70 Cytokine Shift
An extensive array of cytokines is produced at the trophoblast– maternal interface. These cytokines regulate maternal immune responses and may play an important role in successful pregnancy outcome. The balance between Th1 (i.e., pro-inflammatory) cytokines and Th2 (i.e., anti-inflammatory) cytokines is thought to be crucial for determining the success or failure of a pregnancy. It is believed that, for the continuous normal development of pregnancy, the production of inflammatory and potentially harmful Th1 cytokines, such as IL-2, TNF-α, and IFN-γ, is suppressed, whereas production of anti-inflammatory cytokines such as IL-4, IL-6, and IL-10 is enhanced.
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Chapter 41 Recurrent Pregnancy Loss Table 41-1 Common Thrombophilias Possibly Associated with Recurrent Pregnancy Loss Thrombophilia
Inheritance
Prevalence*
Risk of DVT†
Factor V Leiden G1691A mutation (activated protein C resistance)
Autosomal dominant
2–15%
3–8×
Factor II G20210A mutation (prothrombin mutation)
Autosomal dominant
2–3%
3×
MTHFR C677T and A1298C mutation (hyperhomocysteinemia)
Autosomal recessive
11%
2.5–4×
Antithrombin deficiency
Autosomal dominant
0.02%
25–50×
Protein C deficiency
Autosomal dominant
0.2–0.3%
10–15×
Protein S deficiency
Autosomal dominant
0.1–0.2%
2×
Elevated factor VIII
X-linked
5–15%
5×
*Prevalence is in the general population; however, significant ethnic differences are known. † Risk of deep vein thrombosis in the heterozygous nonpregnant individual with the listed thrombophilia compared with a nonpregnant individual without the thrombophilia.
Local Immunosuppression
According to this theory the mother’s T cells assume a reversible tolerant state in pregnancy, in which they no longer recognize paternal antigens; after delivery, the immune system returns to normal.71
Microbiologic Factors Certain infectious agents have been identified more frequently in cultures from women who have had spontaneous pregnancy losses.72 These include Ureaplasma urealyticum, Mycoplasma hominis, and Chlamydia. Other less frequent pathogens include Toxoplasma gondii, rubella, herpes simplex virus, measles, cytomegalovirus, Coxsackievirus, and Listeria monocytogenes. It is important to be aware that none of these pathogens have been causally linked to recurrent pregnancy loss. Because of the clear association with sporadic pregnancy losses and the ease of diagnosis, women with recurrent pregnancy loss should be cultured for the three most common organisms and both partners should be treated if positive.
Thrombophilic Factors The hemostatic system appears to play an important role in both the establishment and maintenance of pregnancy. Thrombophilia is defined as a tendency to thrombosis. Several authors have found an association between thrombotic predispositions and recurrent pregnancy loss. The proposed mechanisms for fetal loss include inhibition of the thrombolytic system, placental thrombosis, placental infarction, abnormal prostacyclin metabolism, and direct cytotoxic effects.73 Because maternal intervillous blood flow does not develop significantly before 8 weeks’ gestation, the theoretical role of thrombophilic defects in first-trimester abortion has been questioned. However, two recent meta-analyses of thrombophilias and early recurrent pregnancy loss established a significant association.74,75 Other obstetric complications associated with thrombophilia are midtrimester abortions, stillbirth, severe preeclampsia, intrauterine growth restriction, and placental abruption.74–76 The most common inherited thrombophilias are heterozygosity for factor V Leiden (G1691A), factor II-prothrombin mutation (G20210A), and hyperhomocysteinemia (thermolabile MTHFR C677T and A1298C). Other possible abnormalities leading to hypercoagulable states that may be associated with recurrent
miscarriage include antithrombin deficiency, protein C deficiency, protein S deficiency, and elevated factor VIII (Table 41-1). Factor V Leiden Mutation
In 1994, the factor V Leiden mutation was discovered to be a very common single-gene predisposition to thrombosis.77 Roughly 3% to 6% of individuals of European ancestry carry this mutation. The Leiden mutation is a single nucleotide substitution in the factor V gene at nucleotide 1691 (G to A) that causes an amino acid substitution (glutamine for arginine) at position 506 in the factor V molecule. In normal clotting, activated protein C (APC) inactivates factor Va and VIIIa by cleavage at specific sites. In the presence of the mutation of factor V, the cleavage of this factor is inhibited, leading to enhanced thrombin generation and increased clot formation. The inheritance of the mutation is autosomal dominant. Carriers of factor V Leiden mutation are at greater risk of fetal loss and stillbirth. Heterozygotes for the mutation have a twofold higher risk of experiencing fetal loss or miscarriage.78 Prothrombin G20210A
In 1996, an additional factor involved in the etiology of thrombophilia was discovered: a point mutation, G to A at nucleotide position 20210 in the 3′-untranslated region of the prothrombin gene.79 This mutation is associated with higher plasma prothrombin concentrations, augmented thrombin generation, and increased risk of venous and arterial thrombotic disease. Heterozygosity for the mutation is present in 2% to 3% of the white population. Hyperhomocysteinemia
Homocysteine is a sulfhydryl nonessential amino acid formed during metabolism of methionine. The levels of homocysteine are increased in a number of inherited and acquired conditions. Hyperhomocysteinemia is associated with the development of venous and arterial thrombosis.80 Homocysteine levels fall during normal pregnancy, and this fall is independent of folate intake.81 High homocysteine levels have been associated with a number of pregnancy-related complications, including neural tube defects, placental infarcts, intrauterine growth restriction, and placental abruption. Folate deficiency is the most common acquired cause of hyperhomocysteinemia. Among the genetic causes a common
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Section 6 Infertility and Recurrent Pregnancy Loss one is a polymorphism that results from a C to T substitution at nucleotide position 677 in the MTHFR gene that converts alanine to a valine residue.82 Individuals homozygous for the mutation (6% to 12% of whites) have significantly elevated plasma homocysteine levels and are prone to the early development of arteriosclerosis. The reduced MTHFR activity and subsequent hyperhomocysteinemia may only be evident in the presence of folate deficiency or exacerbated vitamin B6 or B12 deficiency.83 Adequate folate supplementation may prevent phenotypic expression of the mutation. It has been suggested that maternal hyperhomocysteinemia interferes with embryonic development through defective chorionic villus vascularization.84 A meta-analysis of the association between MTHFR and pregnancy loss before 16 weeks’ gestation suggests a weak association, with an odds ratio (OR) of 1.4 (95% CI, 1.0–2.0); however, the association between elevated fasting plasma homocysteine and early pregnancy loss was significant, with an OR of 2.7 (95% CI, 1.4–5.2).78,85 Antithrombin Deficiency
Antithrombin (previously called antithrombin III) is a serine protease inhibitor produced by the liver with naturally occurring anticoagulant properties. It inhibits thrombin as well as factors Xa, IXa, XIa, and XII and also accelerates the dissociation of the membrane bound tissue factor–VIIa complex. The antithrombin deficiency is inherited in an autosomal dominant fashion. The prevalence of heterozygous carriers is estimated at 1/2000 to 1/5000.86 It is present in 1% of patients with venous thromboembolism and is the most thrombogenic of the inherited thrombophilias, with a 50% lifetime risk of thrombosis.87 Antithrombin deficiency has been associated with an increased risk for stillbirth (OR, 5.25; 95% CI, 1.5–18.1) and fetal loss (OR, 1.7; 95% CI, 1.0–2.8).88 Protein C and Protein S Deficiency
Protein C and protein S are vitamin K-dependent serine protease inhibitors synthesized in the liver. Protein S is also made in endothelial cells and megakaryocytes. Protein S and protein C both exert their antithrombotic effects at those steps in the coagulation cascade that involve conversion of factor X to Xa and conversion of prothrombin to thrombin. The prevalence of protein C deficiency in the general population is 0.15% to 0.8%; prevalence is 2.7% to 4.6% in patients with a history of venous thromboembolism.86 The prevalence of protein S is less than 0.1% in the general population but is 2.2% in patients with a history of venous thromboembolism. Protein S and protein C deficiency do not appear to increase the risk of first-trimester miscarriages but are associated with an increased risk of second-trimester miscarriage and stillbirth.88,89 Combined Thrombophilia
616
The combination of thrombophilic states appears to increase the risk of recurrent pregnancy loss.88 In one study, although factor V Leiden was more common in women with pregnancy loss, factor II G20210A and homozygosity for MTHFR C677T contributed to pregnancy loss only when associated with other thrombophilic defects.90
Secondary Risk Factors A number of secondary risk factors add to and compound the risk of adverse events. These include certain disease states such as diabetes and antiphospholipid antibody syndrome. Physiologic or iatrogenic states such as estrogen treatment (oral contraceptives, hormone replacement), pregnancy, obesity, and the postoperative state will also contribute to the risk of an adverse event. In individuals with inherited risk factors, every effort should be made to reduce or eliminate any secondary risk factors.
Male Factor Male factors potentially contributing to recurrent abortion are largely unexplored. It is known that chromosomal abnormalities limited to spermatogenic cells and not detected in somatic chromosomes are found in approximately 6% of patients in whom meiotic studies are performed.91 Preliminary data from assisted reproductive technology techniques appear to suggest that a paternal component may be implicated in pregnancy loss. Various studies looking the outcome of IVF and intracytoplasmic sperm injection (ICSI) treatment cycles have shown that there is a correlation between sperm DNA integrity and outcomes of these cycles.92,93 There also appears to be an increased risk of spontaneous abortion in women whose partners have poor sperm morphology. The ultrastructural studies of spermatozoa in these studies showed defects of chromatin condensation and irregular nuclei with vacuoles.94 These reports suggest that abnormal sperm chromosomes may be associated with recurrent pregnancy loss.
LIFESTYLE ISSUES AND ENVIRONMENTAL TOXINS Couples experiencing recurrent pregnancy loss are often concerned that toxins within the environment may have contributed to their reproductive difficulty. It is important that healthcare providers counseling patients about exposures to substances in the environment have current and accurate information to respond to these concerns.
Cigarette Smoking Cigarette smoking reduces fertility and increases the rate of spontaneous abortion. The data evaluating smoking and miscarriage are extensive and involve approximately 100,000 subjects. Although the studies are clinically heterogeneous, they nevertheless suggest a clinically significant detrimental effect of cigarette smoking that is dose-dependent, with a relative risk for miscarriage among moderate smokers (10 to 20 cigarettes a day) being 1.1 to 1.3.95
Alcohol Consumption Alcohol consumption of more than two drinks per day is associated with a risk of spontaneous abortion twice that in nonalcohol-consuming controls.96 The minimum threshold dose for increasing the risk of spontaneous abortion appears to be 2 ounces of alcohol per week.97 When both personal habits, cigarette smoking and alcohol, are utilized in the same individual, the risk of pregnancy loss may increase fourfold. Couples should be
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Chapter 41 Recurrent Pregnancy Loss counseled concerning these habits and strongly encouraged to discontinue these before attempting subsequent conception.98
Caffeine Intake There is no evidence that modest caffeine intake (up to 150 mg/day or 1.5 cups of coffee per day) is associated with an increased risk for first-trimester spontaneous abortion or fetal malformations. Several studies have shown, however, that caffeine in excess of 300 mg/day (3 cups of coffee per day) is associated with a modest increase in spontaneous abortion, but it is not clear if this relationship is causal.99
Ionizing Radiation The studies of atomic bomb survivors in Japan showed that in utero exposure to high-dose radiation increased the risk of spontaneous abortions, premature deliveries, and stillbirths.100,101 Diagnostic X-rays in the first trimester delivering less than 5 rads are not teratogenic.102 Large doses (360 to 500 rads) used in therapeutic radiation, however, induce abortion in offspring exposed in utero in the majority of cases. Adverse effects of chronic low-dose radiation on reproduction have not been identified in humans.95
Organic Solvents Organic solvent is a broad term that applies to many classes of chemicals. Perchloroethylene, toluene, xylene, and styrene have all been linked to adverse reproductive outcomes in laboratory animals and in humans. Solvent intoxication is an established occupational hazard in painters and workers in the rubber, semiconductor, and dry-cleaning industries.95 In a meta-analysis of published studies from 1966 to 1994, an overall OR of 1.25 indicated that maternal occupational exposure to organic solvents by inhalation was associated with a small increased risk for spontaneous abortion.103 Overall, organic solvents as a class and toluene in particular are teratogenic at high exposure levels. There is no conclusive evidence that low-level exposure increases the risk of congenital malformations or other adverse reproductive outcomes.95
Heavy Metals Exposure to organic mercury compounds such as methyl mercury or ethyl mercury may occur through consumption of contaminated fish or through the release from batteries, thermometers, and dental amalgams containing mercury. Methyl mercury crosses the placenta and accumulates in embryonic and fetal tissues, particularly in the brain, at concentrations exceeding those in the mother and can cause abnormal neurologic development. In nonhuman primates chronically treated with low-dose methyl mercury, reproductive failure was more likely to occur than in nontreated controls.104 There appears to be no similar association with human environmental exposure.105 Although federal guidelines are eliminating the use of lead, exposure can still occur from residual soil contamination from a variety of sources, including lead solders, pipes, storage batteries, lead-based paints, dyes, and wood preservatives. Exposures to high levels of lead are known to cause embryotoxicity, growth and mental retardation, and increased perinatal mortality. Women
exposed to high concentrations of lead were known to have a higher risk of miscarriages in the 19th century. In fact, lead pills were sold as an abortifacient in the late 1800s and early 1900s.95 Lead concentrations in maternal blood should not exceed 25 g/dL. Federal standards mandate that women should not work in areas where air lead concentrations reach 50 g/cm3 because this may result in blood concentrations above 25 to 30 g/dL.106
Other Exposures Adequately controlled prospective studies demonstrated that exposure to electromagnetic fields and video display terminals was not associated with increased pregnancy loss.107 Air travel, microwave radiation, and ultrasound exposure do not appear to increase the risk of spontaneous abortion. There is also no evidence for an increased incidence of spontaneous abortion with consumption of chemical sweeteners (aspartame, saccharin) or chocolate.95 Associations between maternal exposure to pesticides and adverse reproductive outcomes are speculative and remain inconclusive.108
EVALUATION FOR PREGNANCY LOSS The evaluation of healthy women after a single loss is usually not recommended because this is a relatively common, sporadic event. The risk of another pregnancy loss after two miscarriages is only slightly lower (24% to 29%) than that of women with three or more spontaneous abortions.4,109 Therefore, evaluation and treatment can reasonably be started after two consecutive miscarriages. When the clinician makes the decision to initiate an evaluation for recurrent pregnancy loss, it is recommended that complete diagnostic testing be performed. This obviously includes a complete history, including documentation of prior pregnancies, any pathologic tests that were performed on prior miscarriages, any evidence of chronic or acute infections or diseases, any recent physical or emotional trauma, history of cramping or bleeding with a previous miscarriage, any family history of pregnancy loss, and any previous gynecologic surgery or complicating factor. A summary of the diagnosis and management of recurrent pregnancy loss includes an investigation of genetic, endocrinologic, anatomic, immunologic, microbiologic, iatrogenic, and thrombophilic causes (Table 41-2).
Genetic Karyotyping of couples is part of the evaluation of recurrent pregnancy loss. Chromosomal abnormality in one of the parents can be found in up to 3% to 5% of couples who experience multiple spontaneous abortions. Cytogenetic analysis of aborted fetal material is also very important because this may have important prognostic implications and may direct future interventions. An abnormal karyotype is usually a sufficient explanation for a nonviable pregnancy and also may suggest karyotypic anomalies in the parents. The cytogenetic analysis of the aborted fetus depends on conventional tissue culturing and karyotyping. This technique is laborious and is subject to problems such as external contamination, culture failure, and selective growth of maternal cells. The efforts to develop methods to avoid such difficulties include the application of comparative genomic hybridization technology to recurrent pregnancy loss.110
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Section 6 Infertility and Recurrent Pregnancy Loss Table 41-2 Diagnosis and Management of Recurrent Pregnancy Loss
Etiology
Diagnostic Evaluation
Genetic
Karyotype partners
% Recurrent Pregnancy Loss
Genetic counseling Donor gametes, PGD
15–20%
Septum transection Myomectomy Lysis of adhesions
8–12%
Progesterone
Karyotype POC Anatomic
Hysterosalpingogram Hysteroscopy Sonohysterography Transvaginal 3D US
Endocrinologic
Midluteal progesterone Thyrotropin Prolactin
Levothyroxine Bromocriptine, Cabergoline Metformin
Fasting insulin: glucose Day 3 FSH, estradiol Immunologic
Lupus anticoagulant Antiphospholipid antibodies Embryotoxicity assay*
Therapy
3–5%
Counseling 15–20%
Aspirin Heparin + aspirin IV gamma globulin*
Immunophenotypes* Microbiologic
Cervical cultures
5–10%
Thrombophilic
Antithrombin activity Protein C activity Protein S activity Factor V Leiden mutation Factor II (prothrombin) mutation Hyperhomocysteinemia
8–12%
Psychologic
Interview Questionnaire
Varies
Support groups Counseling
Iatrogenic
Tobacco, alcohol use
5%
Eliminate consumption Eliminate exposure
Exposure to toxins, chemicals
Antibiotics
Heparin + aspirin LMW heparin
Folic acid
RPL = recurrent pregnancy loss; POC = products of conception; PGD = preimplantation genetic diagnosis; 3D US = three-dimension ultrasonography; FSH = follicle-stimulating hormone; LMW = low molecular weight. *Indications for testing and treatment are not clearly established
This technique bypasses tissue culturing because it depends on DNA isolation from samples and provides a whole genome screen for chomosomal abnormalities.111
Endocrinologic
618
The diagnostic testing should include TSH and prolactin levels. Endometrial biopsy 10 days after LH surge or after day 24 of an idealized 28-day cycle is indicated for the diagnosis of luteal phase defect. The out-of-phase histology should be demonstrable in two consecutive cycles for the diagnosis of luteal phase defect. Recent data have challenged the entire concept of an endometrial biopsy for the diagnosis of a luteal phase disorder (see Chapter 8). In practice, many clinicians will use a midluteal progesterone level of al least 10 ng/mL to rule out a luteal phase defect. The fasting glucose-to-insulin ratio is recommended in patients with oligomenorrhea or with other signs and symptoms of PCOS. In obese PCOS patients and in patients
with a glucose/insulin ratio less than 4.5, a 2-hour glucose tolerance test should be obtained. Evaluation of ovarian reserve is performed using day 3 FSH and estradiol levels. FSH over 15 mIU/mL and serum estradiol concentrations over 80 pg/mL on day 3 are associated with reduced oocyte numbers. Alternatively, clomiphene citrate challenge test (clomiphene citrate 100 mg daily administered on cycle days 5 to 9) may be used for evaluation of ovarian reserve. FSH levels are measured on day 3 and 10 and levels less than 15 mU/mL are considered normal.
Anatomic Anatomic causes of recurrent pregnancy loss are typically diagnosed using ultrasonography, hysterosalpingography (HSG), or sonohysterography. Hysteroscopy, laparoscopy, or magnetic resonance imaging (MRI) can also be performed as needed. Recently, transvaginal three-dimensional ultrasonography has been introduced and has allowed accurate and noninvasive diagnosis of congenital uterine anomalies. Transvaginal ultrasound should be a routine part of every workup for recurrent pregnancy loss. This minimally invasive technique can accurately diagnose uterine anomalies and leiomyomas and can suggest endometrial polyps. When the endometrial lining appears thickened or irregular, sonohysterogram is indicated. Saline infusion sonohysterography involves transcervical instillation of fluid into the uterus during transvaginal ultrasound examination. The technique delineates the internal contours of the uterine cavity and provides concomitant visualization of the outer surface of the wall of the uterus. It provides more information about uterine abnormalities than HSG or ultrasound alone. Ideally, it is performed early in the follicular phase of the menstrual cycle after cessation of menses. Hysterosalpingography is used to evaluate tubal patency and can also detect submucous leiomyomas, most uterine malformations, and intrauterine adhesions. Septate and bicornuate uterus cannot reliably be differentiated by HSG, because only the contour of the uterine cavity can be determined. The external contour of the uterine fundus must be demonstrated by ultrasound or laparoscopy. In sexually active women, HSG is performed early in the follicular phase of the menstrual cycle after cessation of menses. Taking a nonsteroidal anti-inflammatory agent (ibuprofen 600 to 800 mg) 1 hour before the procedure has been shown to significantly decrease discomfort (see Chapter 29). Hysteroscopy allows the diagnosis of many intrauterine abnormalities and, if done with adequate anesthesia, their simultaneous treatment. In addition to endometrial polyps and intracavitary leiomyomas, uterine anomalies can be visualized. Unfortunately, there is no way to accurately differentiate between a septate and bicornuate uterus by hysteroscopy. If the external contour of the uterine fundus has not been previously determined, simultaneous laparoscopy is necessary to visualize the uterine fundus. Modern imaging techniques can be used before hysteroscopy to determine the uterine contour.112 MRI and ultrasound have been used to measure uterine dimensions and are less invasive than laparoscopy. These techniques have the added potential advantage of being able to quantify the morphologic defect and
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Chapter 41 Recurrent Pregnancy Loss Table 41-3 Clinical and Laboratory Characteristics of Antiphospholipid Antibody Syndrome Clinical
Laboratory
Pregnancy morbidity ⱖ 1 unexplained death at ⱖ 10 weeks or delivery at ⱕ 34 weeks with severe PIH or three or more losses before 10 weeks
IgG aCL (ⱖ 40 GPL) IgM aCL (ⱖ 40 MPL) Positive lupus anticoagulant test
Thrombosis Venous Arterial, including stroke
Anti-B2 glycoprotein-I IgG or IgM
Patients should have at least one clinical and one laboratory feature at some time in the course of their disease. Laboratory tests should be positive on at least two occasions more than 12 weeks apart. GPL=IgG phospholipid units; MPL=IgM phospholipid units, PIH=pregnancy-induced hypertension. Modified from Miyakis S, Lockshin MD, Atsumi T, et al: International consensus statement on an update of the classification criteria for definite antiphospholipid syndrome. J Thromb Haemost 4:295–306, 2006.
Thrombophilia Because thrombophilias are thought to be responsible for more than half of maternal venous thromboembolisms in pregnancy, all patients with a personal or family history of thromboembolic events should be tested. Testing may also be prompted by obstetric complications such as stillbirth, multiple recurrent pregnancy loss, or after thrombophilia is diagnosed in a family member. The recommended evaluations are: ●
● ●
●
●
●
estimate the likely success of surgical intervention. Threedimensional ultrasound has been compared to HSG and laparoscopy in several studies and has shown a high level of agreement in the diagnosis of congenital uterine anomalies.113,114
Immunologic An international consensus on classification criteria for definite antiphospholipid antibody syndrome was published in 2006.115 According to this criteria, one or more clinical and laboratory features must be present for the diagnosis of antiphospholipid antibody syndrome (Table 41-3). Clinical features must include one or more confirmed episodes of vascular thrombosis (venous, arterial, small vessel; or pregnancy complications (three or more consecutive spontaneous pregnancy losses at less than 10 weeks’ gestation, or one or more fetal deaths at greater than 10 weeks’ gestation, or one or more preterm births at less than 34 weeks’ gestation secondary to severe preeclampsia or placental insufficiency). Laboratory features should include positive plasma levels of anticardiolipin antibodies (IgG or IgM at greater than 40 phospholipid units) or positive plasma levels of lupus anticoagulant. The laboratory abnormalities should be present on two or more occasions at least 12 weeks apart. The testing for the presence of antinuclear antibodies does not appear to be useful because the pregnancy outcome is not different in women with and without the antibodies. Testing for other antiphospholipid antibodies is indicated in women with recurrent pregnancy loss and known autoimmune disease. Testing for Th-1and Th-2 profiles, parental HLA profiles, alloantibodies, antiparental cytotoxic antibodies, or embryotoxic factor assessment are not clinically justified.
Microbiologic Because of the positive association of certain microorganisms with spontaneous pregnancy loss, women with recurrent pregnancy loss should be screened for chlamydia, mycoplasma, and ureaplasma using cervical cultures or polymerase chain reaction (PCR) for detection.
Factor V Leiden screening with activated protein C resistance using a second-generation coagulation assay. This is probably the most cost-effective approach. Patients with a low APC resistance ratio (<2.0) should then be genotyped for the factor V Leiden mutation. Prothrombin G20210A gene mutation using PCR Antithrombin activity with normal levels between 75% and 130% Protein S activity with normal levels between 60% and 145% Protein C activity with normal levels between 75% and 150% Fasting plasma homocysteine. Normal homocysteine levels range between 5 and 10.4 micromol/L. Hyperhomocysteinemia is classified as moderate (10.4–30 μmol/L), intermediate (30–100 μmol/L), and severe (>100 μmol/L).
TREATMENT OF RECURRENT PREGNANCY LOSS The treatment of recurrent pregnancy loss should be directed at the cause. Given the good outcome for most couples with unexplained recurrent abortion in the absence of treatment, it is difficult to recommend unproven therapies, especially if they are invasive and expensive.44 Explanation and the appropriate emotional support are possibly the two most important aspects of therapy. In fact, in one study, antenatal counseling and psychological support for couples with recurrent abortion and no abnormal findings resulted in a pregnancy success rate of 86% compared with a success rate of 33% for women who were given no specific antenatal care.44
Genetic Causes It is important to include genetic counseling as part of any treatment plan. The rate of recurrence of miscarriage often depends on the actual genetic abnormality discovered. Some couples with a known translocation or inversion can have a good pregnancy outcome. Others may need to turn to sperm or oocyte donation to avoid lethal abnormalities in their offspring.116 A recent development is preimplantation genetic diagnosis (PGD). This is a technique where biopsy of one or two cells from an in vitro embryo at the six- to eight-cell stage is performed for prenatal diagnosis of cytogenetic and mendelian disorders. Women who plan to utilize PGD must undergo IVF to conceive, even if infertility is not an issue for the couple. In some studies, PGD screening for aneuploidy has been shown to increase the implantation rate, lower the spontaneous loss rate, and likely improve pregnancy outcome in couples with recurrent pregnancy loss or IVF failure.117,118 Further investigation is required to confirm these preliminary findings.
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Section 6 Infertility and Recurrent Pregnancy Loss Endocrine Abnormalities The treatment of luteal phase defect is targeted at improving the endometrial responsiveness by enhancing the priming of the endometrium in the follicular phase. Various treatments have been described for luteal phase defect, including ovulation induction with clomiphene citrate or gonadotropins, hCG injection at the time of expected ovulation, and progesterone supplementation both during the luteal phase and first trimester of pregnancy.119,120 If the patient has a persistent luteal phase defect accompanied by hyperprolactinemia, bromocriptine, or cabergoline is recommended as a treatment option.121 It is unclear, however, if any of these treatments increase pregnancy rates in patients with recurrent miscarriage. A meta-analysis of randomized trials of pregnancies treated with progestational agents failed to find any evidence for a positive effect on the maintenance of pregnancy.122 Nevertheless, some physicians choose to administer progesterone either as intravaginal suppositories (50 to 100 mg twice daily starting the third day after LH surge and continuing for 8 to 10 weeks), as intramuscular injections (50 mg IM daily), or as orally administered micronized progesterone (100 mg orally two or three tablets daily). It should be mentioned that as many as 60% to 70% of women diagnosed with a luteal phase defect will carry a viable infant with the next pregnancy. Because there is strong evidence that obesity or insulin resistance are associated with an increased risk of miscarriage, weight reduction in obese women is a first step in the treatment. Metformin seems to improve pregnancy outcome, but the evidence for this treatment is limited to a few cohort studies. Metformin is a Category B medication in the first trimester of pregnancy and appears to be safe. Other endocrine abnormalities, such as thyroid disorders and diabetes, should be corrected before conception.
Anatomic Abnormalities The treatment of congenital and acquired uterine anomalies often involves corrective surgery. Hysteroscopic resection of a uterine septum, hysteroscopic lysis of intrauterine adhesions, and the hysteroscopic removal of endometrial polyps and submucous leiomyomata are recommended for all patients with a history of recurrent abortion. The insertion of an intrauterine balloon catheter for 1 week is recommended after resection of synechiae by some physicians to help prevent reformation of adhesions. During this time antibiotic prophylaxis with doxycycline (100 mg twice a day) is given to prevent endometritis. Patients are also given estrogen and progestin for 1 month (Premarin 1.25 mg daily for 25 days and Provera 10 mg q.d. for the last 10 days). Women with recurrent pregnancy loss and large intramural leiomyomata that distort the uterine cavity in the absence of other abnormalities may also benefit from myomectomy. Unification procedures in cases of uterus didelphys or bicornuate uterus do not appear to improve pregnancy outcomes. Cervical cerclage may be offered to women with a clear history of cervical incompetence or those at high risk for midtrimester loss.
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Antiphospholipid antibody syndrome treatments used for improving pregnancy outcome were originally directed toward suppressing the immune system but more recently have been directed to anticoagulation therapy. A combination of low-dose
heparin (5000 to 10,000 units S.C. every 12 hours) appears to be effective and may reduce pregnancy loss by 54% in women with antiphospholipid syndrome.123 Aspirin alone does not appear to reduce miscarriage rates.124 A randomized, controlled trial comparing low-dose heparin (10,000 units S.C. every 12 hours) to prednisone (20 mg every 12 hours) found them to be equally effective in preventing pregnancy loss; however, treatment was not initiated until after the documentation of fetal heart. Moreover, because patients treated with prednisone experienced more complications (premature rupture of membranes and preeclampsia), it is not the preferred therapy.123 Initiating heparin before conception is potentially dangerous because of the risk of hemorrhage at the time of conception. Aspirin should be started preconceptually and heparin should be started after the first positive pregnancy test.125 Treatment should normally be continued until the time of delivery because these women are at an increased risk for thrombosis. Postpartum thromboprophylaxis is reasonable for a short interval to prevent thrombosis when the risk is high. The adverse reactions associated with heparin include bleeding, thrombocytopenia, and osteoporosis with fracture. Calcium (600 mg twice daily) with added vitamin D supplementation (400 IU twice daily) and weight-bearing exercise are encouraged to decrease the risk of osteoporosis. In any pregnant woman starting on heparin, the platelet count should be monitored weekly for the first 2 weeks and every 4 to 6 weeks thereafter. Low molecular weight heparin (LMWH) appears to be a safe alternative to unfractionated heparin as an anticoagulant during pregnancy. It has a longer half-life, which results in a more predictable anticoagulant response and requires only one daily injection. The frequent monitoring with partial thromboplastin time is not needed, and there is a lower risk of osteoporosis and thrombocytopenia. LMWH does not cross the placenta and appears to be safe to the fetus.126 However, the optimal dose in the clinical setting of antiphospholipid antibody syndrome has not been determined. Observational studies in patients with recurrent pregnancy loss have suggested that intravenous immunoglobulin (IVIG) may be effective.127 However, randomized trials have not confirmed this benefit; therefore, immunotherapy is not recommended for prevention of pregnancy loss at this time.123,128,129 Immunotherapy
Immunotherapy for alloimmune disorders is based on the hypothesis that spontaneous abortion occurs due to a failure of maternal immunologic adaptation to the developing conceptus, resulting in a form of transplantation rejection. No alloimmune mechanism has been unequivocally shown to cause pregnancy loss. Nevertheless, several immunologic treatments have been advocated to improve the live birth rate in women with recurrent pregnancy loss. Three primary types of immunotherapy have been described. Paternal leukocyte immunization was the first immunotherapy utilized to boost maternal immune recognition of the developing conceptus. The value of this treatment has never been proven, and its use is not recommended at this time. Trophoblast immune infusion is another form of active immunization that likewise has not been proven to confer any benefits in women with recurrent pregnancy loss. IVIG infusion is a passive form of immunotherapy that is used in an attempt to produce immunomodulatory effects, including neutralization of circulating antibodies, the inhibition of complement-mediated cytotoxicity,
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Chapter 41 Recurrent Pregnancy Loss and the modulation of release of cytokines from lymphocytes.130 Although some randomized, double-blind studies have shown an increase in successful pregnancy outcomes, other have not confirmed these results.131–133 There is not yet firm evidence to suggest benefit from this form of treatment.134 A Cochrane review of 19 trials of various forms of immunotherapy did not show significant differences between treatment and control groups.135 Corticosteroids are known to suppress NK cell activity and also have anti-inflammatory effects. Oral corticosteroids for treatment of recurrent pregnancy loss have been used in the past but are not recommended because of uncertain efficacy and increase in pregnancy complications.67
Infection Appropriate antibiotic therapy should be instituted when cervical infections are identified. Infections with Mycoplasma, Ureaplasma, and Chlamydia are treated with doxycycline, 100 mg twice daily by mouth for 14 days. Patients who are pregnant or allergic to doxycycline can be treated with enteric erythromycin 400 mg three times daily by mouth for 14 days. Both partners should be treated to prevent reinfection. For those who fail treatment based on a test of cure culture, the options are to extend treatment of both partners to 30 days or to use ofloxacin 300 mg daily for 14 days for both partners.
Thrombophilia Although the association between heritable thrombophilia and recurrent pregnancy loss is still disputed, several studies show that anticoagulation may improve both fetal and maternal outcome. In one study, 50 women with recurrent pregnancy loss and a variety of thrombophilic defects were treated with 40 to 120 mg of enoxaparin daily; in this group the chance of successful pregnancy outcome was 75%, which was significantly better than the 20% historical outcome in these women before the diagnosis of thrombophilia was made.136 In women without a history of prior thrombosis, prophylactic anticoagulation can be obtained with unfractionated heparin or LMWH. Unfractionated subcutaneous heparin administered every 12 hours to achieve a midinterval heparin level of 0.1 to 0.2 U/ml by the protamine titration assay is one option. Another approach is every 12 hour injections of 5000 to 7500 units in the first trimester, 7500 to 10,000 units in the second trimester, and 10,000 units in the third trimester. The dose is reduced if the activated partial thromboplastin time is prolonged. LMWH may be administered as enoxaparin (Lovenox) at 40 to 60 mg subcutaneous daily. The dose should be adjusted by weight in obese patients (1 mg/kg/day). The monitoring goal is to achieve anti-factor Xa levels of 0.1 to 0.2 U/mL 4 hours after the last injection. A second alternative is dalteparin (Fragmin) at 5000 units subcutaneous once daily. The dose should be adjusted by weight in obese patients (200 IU/kg/day). Anticoagulation during labor should be avoided. Unfractionated heparin should be discontinued when labor begins. LMWH should be stopped at 36 weeks’ gestation and replaced with unfractionated heparin to minimize the risk of epidural hematoma from regional anesthesia. If surgery is planned while on LMWH, the medication should be stopped 18 to 24 hours before the procedure and restarted 12 hours after the procedure. Protamine
sulfate infusion can be used to reverse anticoagulation in case of emergency procedures. Patients found to have elevated homocysteine levels should have appropriate supplementation with vitamin B6, vitamin B12, and folic acid prior to pregnancy, and conception can be attempted once homocysteine levels are normalized.137 Treatment should be continued throughout pregnancy and potentially lifelong to prevent thrombophilic events. There are no randomized, controlled trials to support this approach; however, the toxicity of this therapy is negligible and folic acid has proven value in reducing neural tube defects. Prophylactic heparin should be considered in patients with a history of thromboembolism, in those who have a homozygous MTHFR mutation, or patients with adverse pregnancy outcomes who are unresponsive to vitamin supplementation.
Environmental Factors Women who smoke or drink alcoholic beverages should be encouraged to abstain from these activities. If exposed to environmental toxins, individuals should try to eliminate or reduce exposure.
OUTCOME In approximately 70% of all cases of recurrent pregnancy loss, a complete evaluation will reveal a possible etiology.2,138 Abnormal findings during the evaluation should be corrected before attempting any subsequent pregnancy. If no cause can be found, the majority of couples will eventually have a successful pregnancy outcome with supportive therapy alone.44,139 Once a pregnancy occurs, the patient should be monitored closely with evaluation of quantitative hCG levels at least twice and documentation of adequate progesterone levels. Early sonography should be scheduled and any encouraging results should be communicated to the couple. In women with a history of recurrent pregnancy loss, the presence of a normal embryonic heart rate between 6 and 8 gestational weeks is associated with a live birth rate of 82%. Couples who have experienced recurrent pregnancy loss want to know what caused the miscarriage. Unexplained reproductive failure can lead to anger, guilt, and depression. Anger may be directed toward their physician for not being able to solve their reproductive problems. Feelings of grief and guilt following an early loss are often as intense as those following a stillbirth, and parents experience a grief reaction similar to those associated with the death of an adult. The couple should be assured that exercise, intercourse, and dietary indiscretions do not cause miscarriage. Any questions or concerns that the couple may have about personal habits should be discussed. Women who suffer recurrent pregnancy loss have already begun to prepare for their baby, both emotionally and physically, as compared to couples with infertility who have never conceived. When a miscarriage occurs, a couple may have great difficulty informing friends or family about the loss. Feelings of hopelessness may continue long after the loss. Patients may continue to grieve and have episodes of depression on the expected due date or the date of the pregnancy loss. Participation in support groups or referral for grief counseling may be beneficial in many cases (SHARE, Pregnancy and Infant Loss Support, Inc., www.national shareoffice.com).
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PEARLS ●
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A complete evaluation for recurrent pregnancy loss will reveal possible causes in 70% of cases. The complete evaluation (genetic, endocrinologic, anatomic, immunologic, microbiologic, thrombophilic, and iatrogenic) should be initiated when the decision to evaluate a couple is made. Couples with primary recurrent pregnancy loss have identifiable causes just as frequently as couples with secondary
●
●
recurrent pregnancy loss; therefore, both types of couples should be evaluated. Women with two losses have identifiable problems just as frequently as women with three or more losses; thus, an evaluation for causes can be initiated after two losses. If no cause is identified after a complete evaluation, 65% of couples will have a successful subsequent pregnancy.
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90. Sarig G, Younis JS, Hoffman R, et al: Thrombophilia is common in women with idiopathic pregnancy loss and is associated with late pregnancy wastage. Fertil Steril 77:342–347, 2002. 91. De Braekeleer, Dao TN: Cytogenetic studies in male infertility: A review. Hum Genet 6:245–250, 1991. 92. Lopes S, Sun JG, Juriscova A, et al: Sperm deoxyribonucleic acid fragmentation is increased in poor-quality semen samples and correlates with fertilisation in ICSI. Fertil Steril 69:528–532, 1998. 93. Sakkas D, Turner F, Bizzaro D, et al: Sperm nuclear DNA damage and altered chromatin structure: Effect on fertilisation and embryo development. Hum Reprod 13(Suppl4):11–19, 1998. 94. Gopalkrishnan K, Padwal V, Meherji PK, et al: Poor quality of sperm as it affects repeated early pregnancy loss. Arch Androl 45:111–117, 2000. 95. Gardella JR, Hill JA 3rd: Environmental toxins associated with recurrent pregnancy loss. Semin Reprod Med 18:407–424, 2000. 96. Harlap S, Shiono PH: Alcohol, smoking, and incidence of spontaneous abortions in the first and second trimester. Lancet 2:173–178, 1980. 97. Kline J, Shroat P, Stein ZA, et al: Drinking during pregnancy and spontaneous abortion. Lancet 2:176–180, 1980. 98. Ness RB, Grisso JA, Hrischinger N, et al: Cocaine and tobacoo use and the risk of spontaneous abortion. NEJM 340:333–339, 1999. 99. Dlugosz L, Bracken MB: Reproductive effects of caffeine: A review and theoretical analysis. Epidemiol Rev 4:83–100, 1992. 100. Miller RW: Effects of ionizing radiation from the atomic bomb on Japanese children. Pediatrics 41:257, 1968. 101. Yamazaki JN, Schull WH: Perinatal loss and neurological abnormalities among children of the atomic bomb: Nagasaki and Hiroshima revisited, 1949 to 1989. JAMA 264:605–609, 1990. 102. Brent RL: The effects of embryonic and fetal exposure to x-ray, microwaves, and ultrasound. Clin Perinatol 13:615–648, 1986. 103. McMartin KI, Chu M, Kopecky E, et al: Pregnancy oucome following maternal organic solvent exposure: A meta-analysis of epidemiologic studies. Am J Indust Med 34:288–292, 1998. 104. Burbacher TM, Monett C, Grant KS, Mottet NK: Methylmercury exposure and reproductive dysfunction in the nonhuman primate. Toxicol Applied Pharmacol 75:18–24, 1984. 105. Brodsky JB, Cohen EN, Whitcher C, et al: Occupational exposure to mercury in dentistry and pregnancy outcome. J Am Dental Assoc 111:779,1985. 106. CDC: Preventing lead poisoning in young children in the United States. MMWR 34:66, 1985. 107. Schnorr TM, Grajewski BA, Hornung RW, et al: Video display terminals and the risk of spontaneous abortion. NEJM 325:811–813, 1991. 108. Nurminen T: Maternal pesticide exposure and preganancy outcome. J Occupation Environ Med 37:935–940, 1995. 109. Stirrat GM: Recurrent miscarriage. Lancet 336:673–675, 1990. 110. Daniely M, Aviram-Goldring A, Barkai G, Goldman B: Detection of chromosomal aberration in fetuses arising from recurrent spontaneous abortion by comparative genomic hybridization. Hum Reprod 13:805–809, 1998. 111. Bryndorf T, Kirchhoff M, Maahr J, et al: Comparative genomic hybridization in clinical cytogenetics. Am J Hum Genet 57:1211–1220, 1995. 112. Salim R, Jurkovic D: Assessing congenital uterine anomalies: The role of three-dimensional ultrasonography. Best Pract Res Clin Obstet Gynaecol 18:29–36, 2004. 113. Jurkovic D, Geipel A, Gruboeck K, et al: Three-dimensional ultrasound for the assessment of uterine anatomy and detection of congenital anomalies: A comparison with hysterosalpingography and twodimensional sonography. Ultrasound Obstet Gynecol 5:233–237, 1995. 114. Raga F, Bonilla-Musoles F, Blanes J, Osborne NG: Congenital Müllerian anomalies: Diagnostic accuracy of three dimensional ultrasound. Fertil Steril 65:523–528, 1996. 115. Miyakis S, Lockshin MD, Atsumi T, et al: International consensus statement on an update of the classification criteria for definite antiphospholipid syndrome (APS). J Thromb Haemost 4:295–306, 2006. 116. Munne S, Morrison L, Fung J, et al: Spontaneous abortions are reduced after preconception diagnosis of translocations. J Assist Reprod Genet 15:290–296, 1998.
117. Gianaroli L, Magli MC, Ferraretti AP, et al: The role of preimplantation diagnosis for aneuploidies. Reprod Biomed Online 4(Suppl 3):31–36, 2002. 118. Rubio C, Simon C, Vidal F: Chromosone abnormalities and embryo development in recurrent miscarriage couples. Hum Reprod 18:182–188, 2003. 119. Karamardian LM, Grimes S: Luteal phase deficiency: Effect of treament on pregnancy rates. Am J Obstet Gynecol 167:1391–1398, 1992. 120. Kutteh WH: Recurrent Pregnancy Loss. Stamford, Conn., Appleton and Lange, 1998. 121. Roberts CP, Murphy AA: Endocrinopathies associated with recurrent pregnancy loss. Semin Reprod Med 18:357–362, 2000. 122. Goldstein P, Berrier J, Rosen S, et al: A meta-analysis of randomized control trials of progestational agents in pregnancy. BJOG 96:265–274, 1989. 123. Empson M, Lassere M, Craig JC, Scott JR: Recurrent pregnancy loss with antiphospholipid antibody: A systematic review of therapeutic trials. Obstet Gynecol 99:135–144, 2002. 124. Pattison NS, Chamley LS, Birdsall M, et al: Does aspirin have a role in improving pregnancy outcome for women with the antiphospholipid syndrome? A randomized controlled trial. Am J Obstet Gynecol 183:1008–1012, 2000. 125. Kutteh WH: Antiphospholipid antibody-associated recurrent pregnancy loss: Treatment with heparin and low-dose aspirin is superior to lowdose aspirin alone. Am J Obstet Gynecol 174:1584–1589, 1996. 126. Silver RM, Branch DW: Immunologic Disorders. Philadelphia, WB Saunders Co, 1999. 127. Vaquero E, Lazzarin N, Valensise H, et al: Pregnancy outcome in recurrent spontaneous abortion associated with antiphospholipid antibodies: A comparative study of intravenous immunoglobulin versus prednisone plus low-dose aspirin. Am J Reprod Immunol 45:174–179, 2001. 128. Branch DW, Porter TF, Paidas MJ, et al: Obstetric uses of intravenous immunoglobulin: Successes, failures, and promises. J Allergy Clin Immunol 108(4 Suppl):S133–S138, 2001. 129. Triolo G, Ferrante A, Ciccia F, et al: Randomized study of subcutaneous low molecular weight heparin plus aspirin versus intravenous immunoglobulin in the treatment of recurrent fetal loss associated with antiphospholipid antibodies. Arthritis Rheum 48:728–731, 2003. 130. Li TC, Makris M, Tomsu M, et al: Recurrent miscarriage: Aetiology, management and prognosis. Hum Reprod Update 8:463–481, 2002. 131. Coulam CB, Krysa L, Stern JJ, Bustillo M: Intravenous immunoglobulin for treatment of recurrent pregnancy loss. Am J Reprod Immunol 34:333–337, 1995. 132. Jablonowska B, Selbing A, Palfi M, et al: Prevention of recurrent spontaneous abortion by intravenous immunoglobulin: A double-blind placebo-controlled study. Hum Reprod 14:838–841, 1999. 133. Stephenson MD, Dreher K, Houlihan E, Wu V: Prevention of unexplained recurrent spontaneous abortion using intravenous immunoglobulin: A prospective, randomized, double-blinded, placebocontrolled trial. Am J Reprod Immunol 39:82–88, 1998. 134. Daya S, Gunby J, Porter F, et al: Critical analysis of intravenous immunoglobulin therapy for recurrent miscarriage. Hum Reprod Update 5:475–482, 1999. 135. Scott JR: Immunotherapy for recurrent miscarriage. Cochrane Database Syst Rev2003:CD000112. 136. Brenner B, Hoffman R, Blumenfeld Z, et al: Gestational outcome in thrombophilic women with recurrent pregnancy loss treated by enoxaparin. Thromb Haemost 83:693–697, 2000. 137. Quere I, Mercier E, Bellet H, et al: Vitamin supplementation and pregnancy outcome in women with recurrent early pregnancy loss and hyperhomocysteinemia. Fertil Steril 75:823–825, 2001. 138. Jaslow CR, Carney J, Norman L, Fong S, Ke RW, Kutteh WH: Etiology of recurrent pregnancy loss in 1018 women. Fertil Steril 86:S472, 2006. 139. Brigham SA, Conlon C, Farquharson RG: A longitudinal study of pregnancy outcome following idiopathic recurrent miscarriage. Hum Reprod 14:2868-2871, 1999.
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42
Diagnostic and Operative Hysteroscopy: Polypectomy, Myomectomy, and Endometrial Ablation Linda D. Bradley
INTRODUCTION Hysteroscopy is an accurate surgical approach for evaluating the uterine cavity and treating a multitude of abnormalities. At its essence, it involves the transcervical placement of a lens and light system into the uterine cavity while using gas or liquid for distension of the cavity. Modern hysteroscopy is performed almost exclusively with the addition of a camera and video monitoring system. Operative hysteroscopy is performed using an electrosurgical resectoscope or a sleeve with an operating channel to accommodate instruments for grasping, biopsying, or cutting with scissors or laser. Today, in addition to being an excellent diagnostic technique, hysteroscopy has proven to be an effective and minimally invasive treatment for abnormal uterine bleeding, infertility, and early pregnancy loss. Some of the most common uterine pathologic conditions treated by hysteroscopy are polyps and myomas. Even in patients without intrauterine pathology, endometrial ablation, first performed hysteroscopically, has decreased the need for hysterectomy in patients with abnormal uterine bleeding unresponsive to medical therapy. This chapter describes the standard methods for diagnostic and operative hysteroscopy and then offers details of the hysteroscopic treatment of polyps and fibroids, both submucous and pedunculated intracavitary lesions. The chapter also describes techniques for endometrial ablation, including traditional hysteroscopic ablation and several innovative methods.
HISTORY Hysteroscopy, first described in the late 1800s, did not find widespread clinical use for more than 100 years. In 1869, Pantaleoni performed the first diagnostic and therapeutic hysteroscopy when he used a modified cystoscope to look into the uterine cavity and cauterize a hemorrhagic growth.1 Early hysteroscopists used a tube to mechanically distend the uterus for visualization. Near the beginning of the 20th century, Dr. Isidor C. Rubin, a New York gynecologist best remembered for Rubin’s test, first used carbon dioxide (CO2) to distend the uterus for hysteroscopy. Around the same time, Professor C. J. Gauss, a German surgeon and descendant of the famous mathematician, first performed hysteroscopy using fluid distension media.2 However, hysteroscopy did not find widespread acceptance for another half-century.3
In the 1970s interest in hysteroscopy renewed, in parallel with the rapid advancement of diagnostic and operative laparoscopy. Probably the most important advances came in the form of improved methods for distending the uterine cavity, including use of viscous and low-density liquid solutions. Around the same time insufflation machines were designed for CO2 and fluid media that utilized high pressure and low flow, rather than the low pressure and high flow used for laparoscopy.4–6 Carbon dioxide was often used for diagnostic hysteroscopy, and fluid media became the standard for operative hysteroscopy. It was found that isotonic fluid was ideal for most operative procedures, whereas nonconductive hypotonic media was required for electrosurgical procedures. The use of hysteroscopy became widespread in the 1980s with the development of better optics and lighting and the use of video cameras. Operative techniques for various intrauterine pathologic conditions continued to be developed. Most notably among these may be removal of submucous myomas using an enhanced urologic resectoscope,7 removal of uterine septum,8 and endometrial ablation using laser,9 resectoscopic loop,10 or rollerball.11 Today, hysteroscopy has become a standard diagnostic and therapeutic technique performed by most gynecologists.
INDICATIONS Diagnostic Hysteroscopy The most common indications for evaluation of the uterine cavity are abnormal uterine bleeding and infertility. Although hysterosalpingography (HSG) and modern ultrasonography are relatively sensitive in detecting intrauterine anomalies, diagnostic hysteroscopy remains the most accurate method available to visualize the cervical canal and uterine cavity. Today, there remain two schools of thought regarding initial evaluation of the uterine cavity. Although many clinicians utilize HSG, transvaginal ultrasonography, and sonohysterography to diagnose intrauterine abnormalities, many gynecologists continue to utilize diagnostic hysteroscopy in the office setting for this purpose. In addition, most gynecologists combine hysteroscopy with every dilation and curettage (D&C) procedure to exclude previously undetected focal pathology and to verify that previously diagnosed polyps have been completely removed during the procedure.
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Section 7 Reproductive Surgery Operative Hysteroscopy
Distension Media
The two most common indications for operative hysteroscopy are (1) directed biopsy of focal lesions and (2) treatment of intrauterine lesions, including endometrial polyps and intracavitary leiomyomas, uterine septa, and cornual tubal occlusion. Removal of uterine septum and treatment of cornual occlusion with cannulation are covered in Chapters 43 and 47. Less common indications for operative hysteroscopy include retrieval of a “lost” intrauterine device with a retracted tailstring, discussed in Chapter 27. Hysteroscopy has also been used in early pregnancy for chorionic villus sampling. The newest indication is the placement of coils into the intramural section of the tube for permanent sterilization, which is covered in Chapter 28. In the recent past, hysteroscopy was commonly used to perform endometrial ablation. Recently, automated ablation techniques that are not performed hysteroscopically have become more common.
The uterine cavity is a virtual space, which must be distended with either gas or fluid media to visualize the endometrium and intrauterine pathology in three dimensions. In the past, contact hysteroscopy was performed without distension media for diagnostic evaluation of the endometrium based on color, architectural pattern, and contour. Today, diagnostic and operative hysteroscopy are most commonly performed with fluid distension media.
BASIC HYSTEROSCOPIC EQUIPMENT AND TECHNIQUES Types of Hysteroscopes All hysteroscopes incorporate an optical system (including an eyepiece and objective lens) and a light source within a single barrel up to 4 mm in diameter. The most commonly used rigid hysteroscope has an objective lens at the tip offset by 12 to 30 degrees from the horizontal plane, although a “0 degree hysteroscope” is also used and other lens angles are available.
Ridged Hysteroscope A ridged hysteroscope is used with a sleeve, which allows for the input of distension media. A diagnostic sleeve has a diameter of up to 4.5 mm and usually has only a media input channel. An operative sleeve has a diameter of 8 to 9 mm and has three channels: an input and outflow channel for media and a 2-mm operating channel for the use of semirigid instruments. These include scissors, biopsy forceps, and graspers that can be used for a full range of hysteroscopic tasks. Laser fibers and coaxial bipolar electrodes have also been used through the operative channel. A resectoscope, similar to a urologic resectoscope, has a 9-mm diameter sleeve with a built-in mechanism to extend and retract a monopolar electrosurgical device using a thumb lever. The monopolar device can be a 5- to 7-mm cutting loop for removal of polyps, septum, or leiomyoma, or a rollerball or barrel used for endometrial ablation.
Flexible Hysteroscope
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A flexible hysteroscope resembles a short colonoscope with variable sizes ranging from 3.1 mm to 5.0 mm. The larger scope has an instrument port with a diameter of 1.8 mm for the use of very delicate flexible instruments. The hysteroscope tip can be deflected up to 160 degrees using a thumb control near the eyepiece. It is often used in an office setting because of its small diameter (and thus no need for cervical dilation). In addition to diagnostic hysteroscopy, it can be used for fine procedures such as directed endometrial biopsy, chorionic villus sampling, tubal canalization, and removal of a “lost” intrauterine device.
Carbon Dioxide
Carbon dioxide was commonly employed for diagnostic hysteroscopy because it allows for excellent clarity in the absence of bleeding. Compared to fluid media, it allows a wider field of view at lower magnification and is not messy. However, when bleeding occurs it is difficult to clear the lens, resulting in limited visualization. Carbon dioxide is less commonly used today than in the past for several reasons. A major cost disadvantage is that CO2 requires the expense of a specially designed hysteroscopic insufflator that produces higher pressures (up to 100 mm Hg) at relatively low flow rates (40 to 60 mL/min). This is in contrast to laparoscopic insufflators, which are designed to deliver relatively lower pressures (<25 mm Hg) at high flow rates (up to 6 L/min). Another problem associated with the use of CO2 for hysteroscopy is the rare occurrence of fatal gas embolism. Although a small amount of CO2 is rapidly absorbed and cleared from the body via respiration, an open vessel in the uterus can allow enough gas into the venous system to result in fatal heart block.12 To minimize this risk when CO2 is used for hysteroscopy, it has been recommended that the Trendelenburg position should be avoided, the cervix should not be dilated, and no operative procedures should be performed. Dextran 70
One of the first fluid distension media used was high-viscosity dextran 70. A 32% solution of dextran 70 in 10% dextrose in water is a nonelectrolytic, nonconductive fluid with syrup-like consistency that can be used for both diagnostic and operative hysteroscopy. Because of its high viscosity, dextran 70 results in minimal leakage through the cervix and tubes. Because it is immiscible with blood, it allows for excellent visibility during surgical procedures. A syringe with manual pressure is most often used during hysteroscopy to slowly infuse dextran 70. Dextran 70 is rarely used today as hysteroscopic distension media because of several associated problems.13 From an operational perspective, dextran 70 solutions cause instruments such as graspers and scissors to become permanently inoperable if the solution is allowed to dry on the instruments. This problem can usually be avoided by immediate cleaning shortly after finishing the procedure. Fluid overload is one of the most common serious problems that can result from intravascular intravasation of dextran 70. Each 100 mL of dextran 70 absorbed results in an increase in the intravascular volume of 800 mL. For this reason, it is recommended to use no more than 500 mL of the solution during an individual procedure. Another risk of intravascular intravasation of dextran 70 is disseminated intravascular coagulopathy. The mechanism of this uncommon complication is suspected to be toxic effects of dextran 70 on pulmonary capillaries.
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Chapter 42 Diagnostic and Operative Hysteroscopy Finally, allergic reactions to dextran 70 have also been reported. The risk of anaphylaxis while using dextran 70 for hysteroscopy has been estimated to be as high as 1 per 1500 cases.14 Low-Viscosity Fluid
Low-viscosity fluids are the most common distension media used today because they are suitable for both diagnostic and operative hysteroscopy, are relatively inexpensive, and are relatively low risk. Isotonic electrolyte-containing fluids can be used for all operative procedures except those requiring traditional electrosurgery, although technologic advances have allowed its use even with these procedures. Hypotonic nonelectrolyte media is used for most electrosurgery (i.e., resectoscope) procedures. Isotonic electrolyte-containing fluids are the most common distension media used for diagnostic hysteroscopy and operative procedures using mechanical instruments, laser, and more recently available bipolar energy. Two commonly used types are 0.9% sodium chloride and lactated Ringer’s solution. Hypotonic nonelectrolyte-containing fluids are required when the unipolar resectoscope is used, and several types are available. The most common fluids used are 5% mannitol, 3% sorbitol, and 1.5% glycine. The theoretical advantage of 5% mannitol is that it is rapidly broken down by the liver into glycogen and is excreted through the kidney, with a half-life of 100 minutes.15 The advantage of low viscosity fluids over carbon dioxide and hyskon 70 is the ability to easily flush blood, mucus, bubbles, and tissue fragments out of the visual field and uterus. However, proponents of hyskon 70 point out that the miscibility of blood in low viscosity fluids can result in decreased visibility. The major risk of all low-viscosity fluid media is potentially fatal fluid overload from intravascular absorption. Hypotonic nonelectrolyte media has the additional deadly risk of acute hyponatremia. Both fluids therefore require close monitoring of fluid used and fluid recovered at frequent intervals throughout the hysteroscopic case. Some institutions use a fluid management system (e.g., Dolphin II, CIRCON, British Columbia, Canada) for this purpose. When a fluid deficit of 1,000 mL of nonelectrolyte solution is identified, blood should be drawn to determine electrolyte levels, the procedure should be terminated, and consideration should be given to administering diuretics, with close monitoring of electrolytes. Injection of 3 to 4 mL of dilute vasopressin (10 units in 50 mL saline solution) into the cervix decreases both intraoperative bleeding and intravasation for at least 20 to 30 minutes.16
electrode is used to resect leiomyomas or divide a septum. This approach is ideal for resecting dense tissue and maintaining hemostasis. Because this is a monopolar device, it must be used with nonconducting hypotonic distension media. Bipolar and insulated monopolar systems have been developed, with the advantage of working with the safer isotonic distension media. These methods are more expensive because they are based on disposable technology. Several lasers have been developed for endometrial ablation, including the potassium-titanyl-phosphate (KTP), argon, and neodymium:yttrium-aluminum-garnet (Nd:YAG) lasers. Each has relative advantages and disadvantages and tends to be more technically challenging and expensive than electrosurgerical techniques.
DIAGNOSTIC HYSTEROSCOPY For the majority of the 20th century, the only method available for directly visualizing intrauterine pathology short of hysterectomy was the blind procedure of D&C. In the 1970s, dramatic improvements in optical systems, light sources, and distension media allowed the widespread use of hysteroscopy for accurate diagnosis (and often treatment) of intrauterine pathology. In the 1980s, the development of hysteroscopes with smaller diameters (<4 mm) allowed the use of the hysteroscope for diagnosis without the need for either cervical dilation or anaesthesia. As a result, office hysteroscopy has become a common procedure, which has been documented to have the advantages of patient acceptability, diagnostic accuracy, and costeffectiveness.17 Hysteroscopy is particularly useful for identifying focal lesions, which are often missed with endometrial sampling.18
Office Hysteroscopy Office hysteroscopy is comfortable, quick, and associated with low complication rates. The cervix can be made more pliable by the use of oral or vaginal misoprostol to make the procedure more tolerable, especially in women at risk for cervical stenosis. Oral analgesics, such as ibuprofen, are also helpful. A low (<1%) complication rate is noted when office hysteroscopy is performed by skilled physicians. Complications include uterine perforation, infections, excessive bleeding, and complications related to the distension media.19
Common Pathology
Narrow rigid and flexible hysteroscopes with diameters less than 4 mm can often be inserted into the uterus without dilating the cervix. For this reason, they are often used in an office setting using only oral analgesics or with the addition of a paracervical block. For operative procedures, larger hysteroscopes and resectoscopes are used that require cervical dilation before insertion and are therefore used primarily in an operating room under general or regional anesthesia.
The list of lesions that can be visualized hysteroscopically is long and includes endometrial polyps, submucosal and intramural myomas, synechiae, retained products of conception, foreign bodies, endocervical lesions, endometrial atrophy, endometrial hyperplasia, endometrial cancer, arteriovenous malformations, gestational trophoblastic disease, cesarean scar defects, incomplete abortion, and pregnancy. In some cases, endometrial gland openings associated with adenomyosis can be observed. Theoretically, the specificity and positive predictive value of hysteroscopy in cases of abnormal uterine bleeding should be 100%. In practice, however, the false-negative rate is 2% to 4% and is the result of operator error in detecting abnormal endometrial lesions.
Power Sources
Technique
The first, and perhaps most versatile, hysteroscopic power source is unipolar electrosurgery. A resectoscope with a thin loop
A slow and thorough evaluation is important to identify abnormalities of the endocervix, fundus, and tubal ostia. Myomas of
Analgesia and Anesthesia
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Section 7 Reproductive Surgery the endocervix and lower uterine segment can easily be missed with too rapid insertion of the hysteroscope. Likewise, if the hysteroscope is too quickly placed above an intracavitary lesion, it can likewise be missed. Lesion Size
The size of lesions cannot be accurately determined hysteroscopically, in contrast to transvaginal ultrasound. This is because the hysteroscopic eyepiece is focused at infinity, thereby making the objects that are closer appear magnified and objects viewed further away smaller.20 This phenomenon can lead to surprises in the operating room, especially when the size of a lesion, particularly submucosal myomas, may be underestimated. Disappearing Phenomena
False-negative views can occur during hysteroscopy when using CO2 because of the high intrauterine pressures. The disappearing phenomena refers to the flattening of endometrial polyps, resulting in a negative hysteroscopic view. This can be avoided by decreasing the intrauterine pressure at the end of the procedure and reinspecting the endometrial cavity.
HYSTEROSCOPIC POLYPECTOMY Endometrial polyps are benign growths found within the uterine cavity. They are often asymptomatic and can perhaps remain undetected for decades. In women without symptoms, polyps are often found coincidentally when pelvic ultrasonography is performed for unrelated problems such as pain or during the investigation for infertility. Polyps are often symptomatic. However, in women with abnormal uterine bleeding, investigation may lead to their detection. Symptoms most often related to uterine polyps include abnormal bleeding, postcoital staining, chronic vaginal discharge, or dysmenorrhea. Polyp-related bleeding is often characterized by increased clotting, intermenstrual or premenstrual spotting, or heavier menstrual flow. There is good evidence that polyps can decrease fertility and that their removal will improve the chances of pregnancy.21 In addition to women with abnormal bleeding and infertility, other women at increased risk for endometrial polyps include women on tamoxifen therapy and women with endocervical polyps, a quarter of whom will also have endometrial polyps. It is obvious that symptomatic endometrial polyps should be removed. However, it is also important to remove asymptomatic polyps, particularly in postmenopausal women.22 Although the vast majority are benign, endometrial cancer and hyperplasia will be found in approximately 2% of endometrial polyps and are associated with coexisting malignancies elsewhere in the endometrium. In one study of more than 1400 polyps, endometrial cancer was found in 27 polyps (1.8%).22 All but one of these women were postmenopausal, and 26% were asymptomatic.
HYSTEROSCOPIC MYOMECTOMY
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Leiomyomas are the primary indication for more than 40% of the 650,000 hysterectomies performed annually in the United States.23 Submucosal myomas likely account for 10% to 20% of all myomas. Many of these can be removed by operative hysteroscopy. In addition to preserving fertility in many cases, a
Figure 42-1 Hysteroscopic view of a type 0 myoma. It is pedunculated and the total myoma lies within 100% of the endometrial cavity.
hysteroscopic approach is associated with a shorter recovery period, lower complication rate, and lower cost than hysterectomy. For a successful surgical outcome, it is important to identify preoperatively the size, number, location, and depth of intramural extension of uterine myoma. Myoma size, number, and location are determinants of complete resectability, the number of surgical procedures necessary for complete resection, the duration of surgery, and the potential complications from fluid overload.24 Numerous studies have demonstrated that preoperative saline infusion sonohysterography gives more information than hysteroscopy in respect of myomas. Chapter 30 reviews the topic of ultrasonography and sonohysterography in detail.
Hysteroscopic Classification of Myomas A classification system is important to most accurately determine the appropriate method for performing myomectomy and counseling the patient on risk and prognosis. The European Society of Hysteroscopy classification system is based on myoma location and the amount of myoma protruding or encroaching on the endometrial cavity.25 In this system, Type 0 myomas are pedunculated, with the myoma lying completely within the endometrial cavity (Fig. 42-1). Type I myomas are described as sessile, with less than 50% intramural extension (Fig. 42-2). Finally, Type II myomas are submucosal in location, with more than 50% intramural extension. These include transmural myomas, which extend from the submucosal to the serosal edge. When viewed hysteroscopically, Type II myomas appear as a “bulge” into the endometrial cavity. Multiple myomas such as those in Figure 42-3 are not placed within this classification. They should not accessed by hysteroscopy. This system was originally designed to classify myomas exclusively on hysteroscopic appearance. However, this approach has significant limitations. During hysteroscopy, myomas can be compressed and recede into the myometrium as a result of the pressure of the distension media, thereby preventing full visualization of the myoma. For this reason, preoperative evaluation
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Chapter 42 Diagnostic and Operative Hysteroscopy Table 42-1 Hysteroscopic and Sonohysterographic Classification System for Myomas Encroaching Upon the Endometrial Cavity Hysteroscopic Type25
Sonohysterographic Class26
Type 0
Class 1
Pedunculated myomas, where 100% of the myoma lies within the endometrial cavity with no intramural extension
Type I
Class 2
Sessile myomas, with <50% intramural extension
Type II
Class 3
Submucous myomas, with >50% intramural extension
Description
Figure 42-2 Hysteroscopic view of a type I myoma that involves less than 50% of the myometrium.
Figure 42-3 Extirpated uterus showing a large (6 cm) intracavitary myoma with multiple intramural and submucous myomas.
with ultrasonography is required to accurately determine how many myomas are present and how deeply the myomas penetrate the myometrium. An ultrasonographic classification system has been developed for intramural myomas that corresponds in part to the hysteroscopic classification and in part to the hysterosalpingography data26 (Table 42-1). ●
●
Class 1 myomas are intracavitary and do not involve the myometrium. The base or stalk is visible on saline infusion sonohysterography (Fig. 42-4). Class 2 myomas have a submucosal component that involves less than 50% of the myometrium (Fig. 42-5).
Figure 42-4 Class 1 myomas are intracavitary and do not involve the myometrium. The base or stalk is visible with saline infusion sonohysterography.
●
Class 3 myomas have an intramural component greater than 50%. They can be transmural and located anywhere from the submucosal to the serosa. These myomas often appear as a bulge or indentation into the submucosal when viewed hysteroscopically (Fig. 42-6).
Surgical Approach According to Stage The degree of surgical difficulty and thus the risk to the patient is related to the depth of penetration and size of the myomas. Pedunculated hysteroscopic Type 0 or sonohysterographic Class 1 myomas up to 3 cm in dimeter can usually be easily removed hysteroscopically. Larger hysteroscopic Type 0 myomas (>3 cm)
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Figure 42-5 Class 2 myomas have a submucosal component that involves less than 50% of the myometrium.
and hysteroscopic Type I (Class 2 on sonohysterography) myomas can be approached hysteroscopically. However, the risk of fluid intravasation increases as a result of increased surgical time and the opening of myometrial venous channels during resection. Operative hysteroscopy is made more difficult by limited space within the uterus and poor visibility due to an inability to further distend the uterine media and the large amount of myoma “chips” that accumulate within the endometrial cavity. Often, incomplete removal of larger myomas requires two or more separate operative procedures. Only the most experienced hysteroscopist would attempt a hysteroscopic resection of an intracavitary myoma 5 cm or larger. Myomas that are large and multiple (see Fig. 42-3) should not be excised by hysteroscopy. Hysteroscopic resection of hysteroscopic Type II (or sonohysterography Class 3) myomas should only be approached by the most skilled hysteroscopist and are more commonly approached abdominally by laparoscopy or laparotomy. Hysteroscopic removal of Type II myomas is associated with a greater risk of fluid intravasation and uterine perforation and commonly requires two or more procedures for complete removal. Hysteroscopic resection of Type II myomas results in extensive damage to the endometrium, resulting in an increased risk of Asherman’s syndrome as well as decreased fertility and hypomenorrhea. In an attempt to minimize intrauterine adhesions, patients are often treated postoperatively with estrogen and progestin, intrauterine stents, or “second look” hysteroscopy. However, the efficacy of these approaches has not been studied. Because of this risk, hysteroscopic removal of Type II myomas generally should not be used in women who desire future fertility.
Patient Selection The ideal patient for hysteroscopic myomectomy should meet the following criteria: ●
● ●
single intracavitary myoma or one involving less than 50% of the myometrium and up to 3 cm in diameter. uterine size less than 12 to 14 weeks normal hemoglobin and normal electrolytes.
Experienced hysteroscopists can remove multiple intracavitary myomas in women who desire future pregnancy. These patients benefit from a two-stage operative hysteroscopic myomectomy, in which myomas are removed from only one uterine wall at a time. This aim is to decrease the risk of apposition of the uterine walls and the development of postoperative intrauterine synechiae.
Preoperative Medications Cervical Preparation
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Figure 42-6 than 50%.
Class 3 myomas have an intramural component greater
Use of a laminaria or misoprostol is recommended to facilitate dilation. Additionally cervical softening agents decrease the risk of cervical tears, decrease the risk of uterine perforation, and decrease the use of unnecessary force to achieve cervical dilation. The most common complications associated with operative hysteroscopic surgery is cervical laceration (Table 42-2). Laminaria can be inserted into the cervix 12 to 24 hours before surgery. This will facilitate cervical dilation, but requires an extra office visit and cannot be used in women with shellfish or iodine allergy.
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Chapter 42 Diagnostic and Operative Hysteroscopy Table 42-2 Risk of Complications Associated with Endometrial Ablation and Resection13,14
Performing operative hysteroscopic myomectomy requires four essential components: ●
Complication
Rate
Intraoperative Cervical lacerations Uterine perforation Bowel/bladder/vessel injury Fluid overload
4% 1.4% Rare Rare
Postoperative Infection Hematometra
0.4% 1–2%
Delayed Bleeding requiring further surgery Subsequent endometrial cancer
10% Rare
●
Misoprostol can be administered vaginally or orally to soften the cervix, although this indication is not approved by the Food and Drug Administration (FDA). Vaginal misoprostol (200 to 400 μg) given 8 to 12 hours before surgery reduces the need for cervical dilation, decreases cervical complications, and reduces operative time in comparison with controls.27 Alternatively, oral misoprostol (400 μg) can be given 12 and 24 hours before surgery to soften the cervix and make dilation easier.28 Side effects associated with misoprostol include lower abdominal pain and small amounts of vaginal bleeding. Prophylactic Antibiotics
Most surgeons do not routinely administer preoperative prophylactic antibiotics before myomectomy. However, prophylactic antibiotics should be administered to high-risk patients, such as women with a history of pelvic inflammatory disease, prior history of tubo-ovarian abscess, or documented hydrosalpinges. Antibiotics are also indicated for patients with history of artificial joints, hip replacement, or with mitral valve prolapse with regurgitation. Many surgeons will give prophylactic antibiotics if a procedure is anticipated to last more than 30 minutes or incomplete removal of a myoma is planned or found to be necessary intraoperatively.
Technique of Hysteroscopic Myomectomy Techniques for removing pedunculated and submucosal myomas include avulsion, scissors, wire-loop resection with bipolar or monopolar equipment, vaporization, morcellation, and laser vaporization. In many cases, a combination of several techniques is required to facilitate complete removal. Initial techniques utilized large intrauterine graspers such as Corson graspers that avulsed myomas; however, without utilizing a hysteroscope, complete removal cannot be accurately determined. In 1978, Neuwirth first reported the use of the monopolar urologic resectoscope for resection of submucosal myomas.29 Hysteroscopic wire-loop resection still remains the most popular method of removing myomas, but newer techniques are emerging. The development of the continuous flow resectoscope permitted distension of the uterine cavity with fluid and removal of blood and debris. Further improvements in optics, video recording, bipolar technology, and uterine distension systems provided additional safety features for operative hysteroscopic procedures.
● ●
thorough preoperative evaluation of uterine myomas, including a detailed knowledge of the number, size, location, and depth of myoma penetration into the myometrium adequate eye-hand coordination understanding of fluid management knowledge and judgment as to when to discontinue the hysteroscopic approach.
Paracervical Block
Many hysteroscopists place a paracervical block before hysteroscopic myomectomy. A solution of 0.25% bupivacaine is used, and 10-mL aliquots are injected at the 12, 3, 6, and 9 o’clock positions. This appears to dramatically decrease postoperative dysmenorrhea. Vasopressin
A dilute solution of vasopressin (20 mL vasopressin mixed in 100 mL normal saline solution) can also be injected circumferentially in 5-mL aliquots into the cervical stroma at the 12, 3, 6, and 9 o’clock position of the cervix. This use of vasopressin is not FDA approved. Vasopressin has been shown to decrease bleeding and the intravascular absorption of distension fluids, apparently as a result of vasoconstriction.30,31 Repeat injections can be administered every 45 to 60 minutes as needed. Close monitoring of blood pressure, heart rate, and arrhythmias is necessary. Cervical Dilation
Using cervical dilators, the cervix is dilated to accommodate the hysteroscope. Most operative hysteroscopes are #7 to #10 French. Marked cervical stenosis is sometimes encountered in postmenopausal women, those who have undergone prior loop electrosurgical excision procedures or cone biopsies, or nulliparous women. However, even in women with normal cervices, cervicotomy incisions may occasionally be required. Cervicotomy is performed using a knife electrode, making two linear incisions at the 12 and 6 o’clock positions of the cervix, which dilates and facilitates placement of the resectoscope. Abdominal ultrasound may be helpful in guiding cervical dilation in the markedly stenotic cervix and decreases the risk of uterine perforation. Uterine Distension
To minimize intravasation of distension media, the lowest intrauterine pressure (i.e., intrauterine distension) should be used that allows a clear view. In many cases, an intrauterine pressure of 70 to 80 mm Hg will be adequate. In some cases, an intrauterine pressure of 100 to 150 mm Hg may be required for a limited period of time to obtain adequate visibility. Higher intrauterine pressures are acceptable as long as the maximum fluid deficits allowable for electrolyte or electrolyte-free solutions are not superseded. The fluid deficit should be continuously calculated, preferably with an automated system. When electrolyte-free solutions are being used (i.e., glycine, sorbitol, or mannitol), the procedure should be discontinued when a fluid deficit of 1000 mL is reached and serum electrolyte levels should be promptly obtained.
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Section 7 Reproductive Surgery When electrolyte solutions are used (e.g., saline) the procedure should be discontinued when a fluid deficit of 1500 to 2000 mL is reached and a diuretic administered to decrease the risk of pulmonary edema. Intermittently, the intrauterine pressure should be lowered to 30 mm Hg or the least amount of pressure that is possible. This rapid reduction in intrauterine pressure will aid in enucleation of the myoma, via a decompression mechanism that releases the encapsulated myoma from its myometrial bed. The myoma may appear to increase in size. In fact, more myoma protrudes into the endometrial cavity, allowing a more complete resection without having to resect myometrium. The high intrauterine pressure created with automated fluid pumps, elevation of fluid bags, and compression of fluid medium with blood pressure cuffs may create an iatrogenic negative hysteroscopic view, in part by pushing the leiomyoma or other subtle lesions. Decreasing the intrauterine pressure frequently and repeatedly allows the full appreciation of the myoma size. Hysteroscopic View
The operative hysteroscope should be advanced in a clear view and without undue force. A 12- or 30-degree hysteroscope has a forward-oblique view. Many surgeons prefer the 12-degree hysteroscope for diagnostic and operative procedures. Surgeons should visualize the cervix and advance the hysteroscope under direct vision. Visualization of landmarks is critical during operative hysteroscopy. A panoramic inspection of the endocervix, lower uterine segment, endometrial cavity, and tubal ostia should be performed as the hysteroscope is inserted. Prior cesarean section scars should be observed.
Special Techniques Fertility Preservation
If the patient desires fertility, overzealous resection of the myometrium must be avoided. Asherman’s syndrome may occur when large portions of overlying endometrial tissue are resected with a sessile myoma. Patients who desire fertility and have multiple intracavitary myomas, especially those with myomas on opposite walls, may require resection on two separate occasions to minimize chances of intrauterine synechiae developing postoperatively. For women wishing to maintain or preserve fertility who undergo large myoma resection or have resection of “kissing lesions,” many gynecologists will empirically administer highdose estrogen in an effort to re-epithelize the endometrium and decrease the risk of intrauterine adhesions. A typical regimen is conjugated estrogen 0.625 to 1.25 mg twice daily or estradiol 2 mg twice daily for 25 days, followed by 12 days of medroxyprogesterone 10 mg. Another approach is to place a postoperative intrauterine stent. Either a pediatric catheter inflated with 15 to 20 cc or a balloon uterine stent specifically designed for this purpose may be inserted for 7 to 10 days to prevent the juxtaposition of the uterine walls. A final approach is to perform office hysteroscopy within the first 7 to 14 days after extensive myomectomy to evaluate the endometrium for synechiae. If detected early, the adhesions are filmy and easily lysed with the distal tip of the hysteroscope. In some circumstances hysteroscopic visualization every 7 to 10 days may be required until regeneration of the endometrium is confirmed and filmy adhesions treated. When performed too late, dense fibrous adhesions may be encountered, requiring operative hysteroscopic adhesiolysis. Large Myomas
Loop Resection
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Once the submucosal myoma or focal intrauterine pathology is identified, the wire-loop electrode is advanced in clear view and retracted toward the surgeon. The current setting generally used with monopolar current is 60 to 80 watts cutting current and requires an appropriately sized grounding pad. Higher settings may be necessary with very fibrous, dense, or calcified myomas. When the bipolar generator is used, it automatically adjusts the power to default settings. As the wire loop is drawn toward the surgeon, small crescentshaped “chips” or fragments of leiomyoma are created. The whorled fibrous appearance of the leiomyoma is clearly different from the fascicles of soft underlying myometrium. Additionally, increased bleeding from the myometrial bed and fluid intravasation may be encountered if the myometrium is breached. The leiomyoma is shaved until it is flush with the endometrium. Myoma chips can remain free-floating until they interfere with visualization and are then removed with polyp forceps, Corson graspers, suction curette, or with the loop itself. Extreme caution is necessary if an instrument is inserted blindly to retrieve the leiomyoma chips. Care prevents the risk of uterine perforation. All free-floating tissue fragments should be removed for histologic examination to prevent delayed vaginal secretions, malodorous discharge, adhesions, and risk of infection.
Larger myomas (>3 cm) may benefit from being “debulked” initially by using a bulk vaporization electrode (VaporTrode, ACMI, Southborough, Mass.) or by being divided into four quadrants and retrieved with Corson graspers. Vaporization electrodes are grooved or spiked barrel shape, with a number of edges that function like an array of narrow caliber electrodes, each with the ability to vaporize adjacent tissue. Large volumes of tissue are rapidly desiccated and vaporized, eliminating accumulation of tissue fragments. To achieve this result, the power requirements are several times higher. For example, with a Valleylab Force F/X electrode, settings of 200 to 220 watts are necessary. This technique should be avoided at the cornua and isthmus regions to reduce the electrosurgical risk of perforation. Many surgeons use a technique of dividing larger circular myoma into four sections using a straight wire loop. Once the myoma is divided into four pieces, each piece can be avulsed and removed through the dilated cervix. Prostaglandin F2␣ Analogue
Despite evaluation, some myomas are technically challenging to remove or the surrounding pseudocapsule is not well demarcated. Myomas with a significant intramural location require the most experienced hysteroscopic expertise to remove. In recent studies carboprost, a methyl analogue of prostaglandin F2α, showed promise in facilitating enucleation of myomas. This is not an
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Chapter 42 Diagnostic and Operative Hysteroscopy FDA-approved use of the drug. A recent report describes the successful use of carboprost in 10 women to facilitate hysteroscopic myomectomy.32 Carboprost led to contraction of the myometrium and extrusion of the unresectable intramural component into the endometrium, facilitating hysteroscopic resection. Side effects include transient fever, nausea, diarrhea, and vomiting. Additionally, due to strong uterine contractions, visualization was hampered and required increased intrauterine pressures to distend the endometrial cavity and manipulate the resectoscope in some cases. Intraoperative Ultrasonography
Intraoperative ultrasonography guidance during operative hysteroscopy is useful for resection of myomas or septa that are hard to define. Ultrasound guidance may allow resection beyond the limit conventionally defined by hysteroscopy. Bipolar Technology
Bipolar technology enables surgeons to diagnose and treat various benign intrauterine conditions, including myomas and polyps, using electrolyte-containing distension media (i.e., saline solution). Several innovative electrode designs, including ball, twizzle, and spring configurations, deliver bipolar energy through #5 French instrument channels to vaporize, cut, and desiccate tissue. Similar surgical strategies and caveats as discussed for monopolar technology apply when the bipolar technique is used.
Postoperative Management Most patients experience minimal postoperative pain after hysteroscopic myomectomy. Mild cramping will usually respond to nonsteroidal anti-inflammatory drugs (NSAIDs), and few patients will require opiods. Typically patients resume normal activities within 48 hours after surgery. Bathing is permissible immediately after myomectomy and sexual activity can be resumed 1 week postoperatively. Most patients will have a serosanguineous discharge lasting for 1 to 4 weeks after hysteroscopic myomectomy. If an incomplete resection has occurred, some patients may pass pieces of myomas several weeks after the procedure and have prolonged discharge. Patients should be warned of the risk of infection and return for signs of this complication.
ENDOMETRIAL ABLATION Endometrial ablation was developed as a minor surgical procedure to treat women with intractable heavy menses unresponsive to medical management who no longer desire fertility. Each year approximately 200,000 women undergo an endometrial ablation. Compared to hysterectomy, endometrial ablation offers the advantages of avoiding the morbidity and prolonged recovery associated with major surgery and allows conservation of the uterus. In the past decade, methods for endometrial ablation have been developed that do not require hysteroscopy. In patients with relatively normal uteri, these nonhysteroscopic techniques have been found to be just as effective as hysteroscopic techniques, and appear to be safer and less technically demanding. Both traditional hysteroscopic and contemporary nonhysteroscopic methods for endometrial ablation are described here.
Preoperative Evaluation A thorough preoperative evaluation is imperative because many serious diseases can present as abnormal uterine bleeding. The investigation and management of abnormal uterine bleeding is described in Chapter 21. A brief overview is given here to highlight the importance of a proper evaluation before a surgical procedure. The evaluation begins with a detailed history, physical examination, and ultrasonographic imaging. Important laboratory tests for evaluation of women with menorrhagia include a pregnancy test, thyrotropin level, and complete blood count with platelet count. Many clinicians recommend a platelet function screen or a von Willebrand ristocetin cofactor. If the platelet function screen is abnormal, testing for von Willebrand’s disease is indicated. A recent study reported 47% of reproductive-age women with menstrual dysfunction were found to have a hemostatic abnormality such as platelet dysfunction, von Willebrand’s disease, or coagulation factor deficiencies.33 Endometrial Biopsy
Women over age 40 should have an endometrial biopsy to exclude hyperplasia or malignancy. Endometrial biopsy should also be performed in women under age 40 with risk factors for endometrial hyperplasia and cancer, such as diabetes, prolonged steroid use, obesity, protracted history of irregular cycles, unopposed estrogen therapy, or polycystic ovary syndrome. Women who have endometrial hyperplasia with or without atypia should not be offered endometrial ablation.
Risks Complications of endometrial ablation are uncommon, and many are even less common with the newer ablative techniques compared to hysteroscopic techniques. The interoperative risks include fluid overload, uterine perforation, cervical lacerations, and bowel injury (see Table 42-2). These complications are more common in women undergoing traditional hysteroscopic ablation and resection techniques. Postoperative complications include hematometra and infection. Prophylactic antibiotics are often used, but have not been shown to decrease the infection risk. Delayed complications include continued bleeding heavy enough to require repeat ablation or hysterectomy. A concern in the early years of ablation was that the procedure might decrease the ability to make an early diagnosis of cancer of the endometrium by masking early bleeding. Although endometrial cancer has been reported after ablation, delayed diagnosis has yet to be documented. If a woman who has had an endometrial ablation later requires hormone replacement therapy, progesterone therapy is required because the remaining viable endometrium puts the patient at risk for hyperplasia or malignancy if unopposed estrogen is used. Continued menstruation after ablation is not considered to be a complication. The reported amenorrhea rate is as high as 40% after hysteroscopic ablation and nonhysteroscopic methods. Endometrial ablation should only be offered to women who are willing to accept eumenorrhea, hypomenorrhea, or cyclic bleeding rather than amenorrhea as a final clinical result.
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Section 7 Reproductive Surgery Endometrial Ablation Techniques Currently there are eight different methods to perform endometrial ablation. The three first-generation hysteroscopic techniques include electrosurgical endomyometrial resection, electrosurgical rollerball ablation, and laser ablation. Second-generation techniques, also referred to as global methods, were developed that do not use hysteroscopy to perform the ablation. Hysteroscopy is an integral part of only one of these systems (i.e., Hydro ThermAblator). However, many clinicians perform diagnostic hysteroscopy before using any of the global methods. First-Generation Hysteroscopic Endometrial Ablation
In the early 1980s, endometrial ablation was established as an alternative to hysterectomy for treatment of menstrual dysfunction in women with intractable menorrhagia. Mimicking the physiologic effect of Asherman’s syndrome, the ultimate goals of endometrial ablation were to create severe endometrial scarification and secondary amenorrhea. Initially, Goldrath and colleagues reported laser endometrial ablation using the Nd:YAG laser fiber through the operating port of a hysteroscope. However, this method waned in popularity due to costs and riks of complications in less experienced hands.9 Endomyometrial resection utilizing a resectoscope was first reported by DeCherney and Polan in 1983.34 This technique utilizes unipolar electrocautery and is performed with hypotonic nonelectrolyte-containing distension media. This technique was the forerunner of hysteroscopic rollerball endometrial ablation, which has become the “gold standard” to which all emerging endometrial ablation technology is compared. This technique, which also uses a resectoscope, was popularized by Vancaillie in 1989.11 Each of these devices destroys the basalis layer of the endometrium and is designed to result in hypomenorrhea or amenorrhea. Review of the first decade of hysteroscopic ablation revealed relatively good results as well as moderate difficulties. Cumbersome equipment, patient safety, need for highly trained operating room staff, hampered visibility, and both intraoperative and postoperative complications hindered widespread application of hysteroscopic endometrial ablation. Second-Generation Endometrial Ablation Devices
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Second-generation, or global, endometrial ablation refers to destruction of the endometrium with devices placed blindly into the endometrial cavity and usually activated without hysteroscopic guidance. Little or no hysteroscopic skills are required when performing endometrial ablation with second-generation devices. Currently, FDA-approved devices available in the United States considered to be second-generation procedures include systems that use a uterine balloon, hot saline irrigation, cryosurgery, radiofrequency, and microwave. Second-generation technology offers the advantage of shorter procedure times while retaining the acceptable outcome rates, similar to those of traditional rollerball ablation. However, these second-generation devices have limited or no ability to treat intracavitary pathology. Only two second-generation ablation devices currently permit treatment of polyps alone (NovaSure) or polyps plus myomas (Microwave Endometrial Ablation System). For this reason, it is important for clinicians who
routinely use these ablation devices to be skilled in operative hysteroscopy so that intracavitary pathology can be concurrently treated when necessary.
Endometrial Preparation before Ablation The goal of endometrial ablation is destruction of the basalis layer of the endometrium. Under hormonal control, the endometrium varies greatly in thickness throughout the menstrual cycle. The endometrium is thinnest (<4 mm) during menses, gradually increases in the proliferative phase (4–10 mm), and is thickest during the secretory phase (10–15 mm). The amount of stromal edema and debris also increases during the secretory phase and menstruation. Ideally, the patient should be scheduled during the early proliferative phase. Otherwise, hormonal suppression of the endometrium is required to thin endometrium and increase the chances of success of the ablation. Hormonal suppression also appears to improve visualization, reduce operative time, decrease the risk of fluid overload, and increase amenorrhea and hypomenorrhea rates. However, no studies have proven that hormonal suppression improves long-term outcomes. Hormonal options for endometrial suppression include the use of depot leuprolide acetate, danacrine, oral contraceptive pills, and progesterone-only pills 4–8 weeks before surgery. Surgical preparation with suction or sharp curettage immediatedly before ablation has also been used with reported success.
Technique of Hysteroscopic Rollerball Endometrial Ablation The general concept of hysteroscopic endometrial ablation involves thorough destruction of the basalis layer, cornua, and lower uterine segment. Currently there are three methods available to perform hysteroscopic endometrial ablation: rollerball desiccation, endomyometrial resection and desiccation, and laser endometrial desiccation, although the latter technique is rarely used today. For this reason, only the first two techniques are reviewed here. Vasopressin
Vasopressin is used to decrease the risk of fluid absorption, fluid overload, and intraoperative bleeding. A dilute solution of vasopressin (10 units in 50 mL saline solution) is injected as 5-mL aliquots into the stroma of the cervix at 12, 3, 6, and 9 o’clock position. This causes intense arterial and myometrial wall contractions for 20 to 45 minutes Vasopressin is not approved by the FDA for this purpose and should not be used in patients with hypertension. Supplementary Treatments
Uterine cramping is common after endometrial ablation. To decrease postoperative cramping, a paracervical block (0.25% bupivacaine without epinephrine) can be placed and the patient can be given intravenous NSAIDs (ketorolac tromethamine 30 to 60 mg). An antiemetic given during surgery is recommended to decrease postoperative nausea. Rollerball Electrode
The depth that the endometrium is coagulated depends on tissue and equipment factors. Tissue-related factors include
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Chapter 42 Diagnostic and Operative Hysteroscopy endometrial thickness and variations in tissue impedance related to the number of previous passes. Equipment-related factors include the diameter and shape of the electrode, waveform and power utilized, cleanliness of the electrode, time of exposure of the electrode to the endometrium, pressure against tissue, and speed of electrode. Several varieties and shapes of electrodes are available to perform hysteroscopic endometrial ablation, including ball, barrel, ellipsoid, and large caliber loops. Most surgeons perform roller-ball endometrial desiccation with a 3-mm roller-ball probe, with the goal of systematically destroying the entire endometrium to the lower uterine segment and cornual region. Endometrial ablation is performed under direct and constant view of the endometrium with a distension medium that is compatible with the electrical energy used. Monopolar electrosurgical equipment requires the use of nonelectrolyte-containing distension media, such as glycine, sorbitol, or mannitol. Bipolar equipment will only function in the presence of electrolyte-containing media such as saline solution. Electrical Settings
Monopolar ablation is performed at 60 to 100 watts of pure cutting current. Although some surgeons prefer coagulating current, others believe that the interrupted nature of this type of current may cause an uneven amount of protein bonding, theoretically reducing the homogeneity of the tissue effect. Early coagulation of the superficial layers of the tissue can result in increased impedance, further reducing transmission of current to deeper layers.
movement of an activated electrode to decrease the risk of burns to the pelvic viscera. Intermittently, the roller-ball may need to be cleaned and debris evacuated to provide optimal visualization. At the conclusion of the endometrial ablation procedure, the intrauterine pressure is reduced to identify small bleeders, which may be treated with coagulation current.
Technique of Endomyometrial Resection The technique of endomyometrial resection was pioneered by DeCherney and colleagues.10 The 90-degree wire loop, generally 3 to 4 mm deep, is buried into the endometrium, and using 60 to 80 watts of pure cutting current, is advanced under direct view to the lower uterine segment. The endomyometrial junction is shaved off, creating crescent-shaped tissue fragments.
Causes of Endometrial Ablation Failure The majority of patients who undergo endometrial ablation are satisfied with their clinical outcome; at least 90% will notice symptomatic improvement. However, 5% to 10% of patients may ultimately be required to undergo additional intervention, such as repeat ablation or hysterectomy. The most frequently associated factors noted with endometrial ablation failures include the following: ● ● ●
Systematic Plan of Ablation
Following a systematic surgical plan ensures optimal clinical outcomes. Excellent visualization of the entire uterine cavity and endocervix is imperative. All intrauterine landmarks are clearly delineated hysteroscopically before initiating the procedure. Once a panoramic view of the endometrium is accomplished, the surgeon should determine if there is any previously unrecognized pathology. If a subtle lesion is discovered, then a directed biopsy with a wire-loop electrode is performed and the specimen labeled and submitted separately. Once the surgeon visualizes all of the landmarks, the lower uterine segment is cauterized circumferentially to mark the endpoint and lowest level of endometrial ablation therapy. Ablation of the endocervix is avoided to minimize the risk of cervical stenosis. Cervical stenosis can result in cyclic pain, dysmenorrhea and, in severe cases, hematometra. After the lower uterine segment is identified and coagulated circumferentially, the cornua and fundal region are treated initially. The roller-ball is advanced to the fundus and then directed at the cornua utilizing a “touch technique” to desiccate the cornua. It must be remembered that the thinnest region of the uterus is at the cornua and cesarian section scars. Extra care must be taken to avoid forward pressure, which could cause perforation. The most challenging part is the fundus because the roller-ball cannot truly be rolled against the fundus. Next the posterior wall, followed by the lateral walls and anterior walls, is treated. Traditional technique utilizes direct tissue contact, such that one half of the roller-ball is buried in the endomyometrial juncture. Always activate the foot pedal when the electrode is moving toward the surgeon. To avoid the risk of perforation, the surgeon should avoid any forward
● ● ●
inadequate preoperative workup coexisting intramural myomas greater than 3 cm failure to treat intracavitary endometrial polyps or submucosal myomas uterine cavity length greater than 12 cm diffuse adenomyosis lack of hysteroscopic skill.
Endometrial ablation outcomes can be improved by scheduling the procedure immediately after menses. The early proliferative phase yields better results than operating during the secretory phase. Pharmacologic pretreatment with danazol or GnRH analogues also improves outcomes. Hysteroscopic endometrial ablation is an outpatient procedure associated with a rapid return to work, minimal complications, and high patient satisfaction. Approximately 20% to 60% of patients undergoing endometrial ablation with roller-ball techniques will achieve amenorrhea, 65% to 70% will become hypomenorrheic, and 5% to 10% will fail. Approximately 10% of patients treated by endometrial ablation will require a subsequent operation.35 Women receiving appropriate preoperative counseling may find this attractive in treating menstrual disorders.
GLOBAL ENDOMETRIAL ABLATION TECHNIQUES Since December 1997, the FDA has approved the following five devices for endometrial ablation in the United States: ●
●
●
ThermaChoice Uterine Balloon Therapy (UBT) System (Gynecare, Ethicon Inc., Somerville, N.J.) HerOption Uterine Cryoblation Therapy System (CryoGen, San Diego, Calif.) Hydro ThermAblator (HTA) (BEI Medical/Boston Scientific, Natick, Mass.), a hot saline irrigation system
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Section 7 Reproductive Surgery Table 42-3 Patient Selection Criteria and Pretreatment for Global Endometrial Ablation
ThermaChoice UBT System
●
●
Hydro ThermAblator System
NovaSure Endometrial Ablation System
Microwave Endometrial Ablation System
Maximum sounding length
10 cm
10.5 cm
10 cm
10 cm
14 cm
Inclusion of polyps
No
No
No
Yes <2 cm
Yes
Inclusion of submucous myomas
No
No
No
Yes <2 cm
Yes <3 cm
Inclusion of distorted cavities
No
No
No
No
Yes
Congenital malformations
No
No
No
No
Yes
Endometrial pretreatment
Yes (Dilation and curettage)
Yes (Lupron 7.5 mg)
Yes (Lupron 3.75 mg)
No
Yes (Lupron 3.75 mg)
NovaSure Endometrial Ablation System (Novacept, Palo Alto, Calif.), a radiofrequency endometrial ablation system Microwave Endometrial Ablation (MEA) System (Microsulis Medical Ltd., Pompano Beach, Fla.).
Table 42-3 lists the different devices and the specific patient characteristics. In theory, all these devices can be used in an office setting.
ThermaChoice UBT System
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HerOption Uterine Cryoblation Therapy System
The ThermaChoice UBT System was the first of the secondgeneration endometrial ablation technology systems and received FDA approval in 1997. As such, it has the longest clinical data regarding outcomes of any second-generation technology. Initially, the device was made of a latex balloon and lacked an internal impeller; however, an evolution in the technology has occurred. Currently, the device is packaged individually and consists of a single-use silicone balloon catheter with an internal impeller, umbilical cable, and reusable controller that monitors uterine pressure, temperature, and treatment time continually. A variety of anesthesia has been described with this technology, which includes general anesthesia, local paracervical block with intravenous sedation, and regional anesthesia. After the cervix is dilated, uterine cavity length is determined and the balloon is inserted and filled with 5% dextrose in water (D5W). The physician observes the controller and continues to distend the balloon until the intrauterine pressure reaches 160 to 180 mm Hg, with a maximum instillation of 35 mL. Most uterine cavities typically require 6 to 15 mL. After the pressure stabilizes for 30 to 45 seconds, the treatment cycle begins. There is an initial warming cycle when the temperature reaches 87°C (188°F). The physician maintains the intrauterine pressure between 160 and 180 mm Hg by slowly adding more D5W as needed. Higher amenorrhea rates occur when the intrauterine pressure is maintained between 160 and 180 mm Hg during the entire treatment phase. Treatment is completed after 8 minutes, the controller terminates automatically, and the balloon is deflated, removed, and discarded. The physician can monitor temperature, treatment time, and intrauterine pressure continuously. In the FDA trial, a 3-minute suction curettage was used before performing ablation with the ThermaChoice device. More recently, physicians have scheduled during the early proliferative
phase or pretreated with GnRH analogues, oral contraceptive pills, or danacrine. Recent modifications in the balloon, ThermaChoice III, have increased the performance and safety of the device. Enhancements include silicone material, deeper thermal injury, a distensible catheter that holds 35 mL of fluid, and the ability to treat the lower uterine segment and cornua region more effectively. Recent clinical data support a better overall performance with respect to success or amenorrhea using the ThermaChoice III device compared to the ThermaChoice I. Although not originally evaluated for use with myomas, case series have demonstrated efficacy with their presence.36 These data showed a significant and statistically similar reduction in menstrual blood flow and increase in hemoglobin values with no intraoperative complications. With the ThermaChoice III device, the physician must constantly be engaged in the treatment cycle. Uterine contractions likely occur due to heating of the uterine cavity and often precipitously increase the intrauterine pressure. The surgeon should quickly respond to the rising pressure by opening the pressure valve, which releases a small amount of fluid to maintain the ideal pressure. The small catheter size requires little cervical dilation, which minimizes the risk of cervical laceration and uterine perforation. However, in the event of uterine perforation, the pressure drops abruptly, terminating treatment. Safety features incorporated into the device abort the procedure if the pressure reaches 210 mm Hg or if the pressure is less than 45 mm Hg after device activation. If the temperature inside the balloon exceeds 95°C (203°F) for 2 seconds, or falls below 75°C (167°F) for 15 seconds, or is unable to reach 87°C (188°F) within 4 minutes of preheating, the controller automatically terminates the procedure.
HerOption Uterine Cryoblation Therapy System The second global endometrial ablation technology approved by the FDA in April 2001 was the HerOption Uterine Cryoblation Therapy System. This technology uses a cryoprobe and proprietary compressed gas mixture that freezes the endometrium to below 100°C, thereby destroying the endometrial lining. It creates the largest depth of necrosis (9 to12 mm) of the second-generation devices. In the FDA trial, patients were pretreated with a single dose of leuprolide acetate (3.75 mg intramuscularly). The unit
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Chapter 42 Diagnostic and Operative Hysteroscopy consists of a console, a cryoprobe, and disposable sheath that fits over the cryoprobe. FDA guidelines require continuous transabdominal ultrasound guidance to monitor progression of the ice ball created during the procedure. The device requires only 5- to 6-mm dilation for insertion of the probe. After the probe is placed into the uterine cavity, ultrasound images are performed that confirm placement of the device within the uterine cavity. The unit then initiates a 3- to 5-minute prefreezing cycle is activated, which heats the tissue to 37°C. Saline solution is inserted into the device to clear air, and ablation begins. The FDA trial used one 4-minute freeze at the initial cornu treated. A short heat cycle follows each treatment to dislodge the adherent endometrium, followed by one 6-minute freeze at the opposite cornu. Ultrasound monitoring permits individualized monitoring based on progression of the ice ball. The unit terminates treatment automatically when a 10-minute treatment cycle occurs. New treatment protocols incorporating additional treatment of the lower uterine segment may improve amenorrhea rates. No inherent safety mechanism exists to terminate the procedure automatically if perforation is suspected. Patients feel little pain and the procedure can be performed in the office setting. One of the key limitations is the difficulty in visualization of the uterus by ultrasound in obese patients.
Hydro ThermAblator (HTA) System Also approved in April 2001, the Hydro ThermAblator is a software-controlled, hysteroscopic thermal-ablation system composed of an operational unit, heated canister, and sterile procedure set. Additionally, the system requires use of USP 0.9% sodium chloride solution and a small, rigid hysteroscope. Hydrostatic pressure maintains the intrauterine pressure between 50 and 55 mm Hg—below the threshold for opening the fallopian tubes—and provides a measure of safety. During the priming phase, room-temperature saline solution circulates within the system for 2 minutes by way of a gravityflow system. During the active-treatment phase, the heating element is activated. When the saline temperature reaches 80°C, the 10-minute treatment cycle is initiated, which increases the temperature to 90°C continually. After the treatment is completed, a cool-down period begins. After 1 minute, the posttreatment flush phase is completed and the device is withdrawn. This minimizes the risks of cervical, vulvar, and vaginal burns. Safety features of the HTA, unlike other second-generation devices, include continuous hysteroscopic monitoring before, during, and after therapy. The turbulence of the endometrial debris and heated saline solution may create a compromised hysteroscopic view. In the FDA trial, cervical ulcerations due to thermal damage were reported in 13% of patients and resolved within 1 month without additional therapy. Patients were treated with a double dose of leuprolide acetate (7.5 mg intramuscularly) that was administered 3 weeks before ablation. Severe burns to the vagina or external genitalia have been reported with this device.
NovaSure Endometrial Ablation System The NovaSure Endometrial Ablation System received FDA approval in September 2001. The NovaSure system consists of the disposable device, radiofrequency (RF) controller, CO2
canister, desiccant, footswitch, and power cord. The device delivers RF energy to treat the endometrial lining of the uterine cavity. The disposable device is inserted transcervically into the uterine cavity. The uterine cavity length (measured during sounding) and width (measured by the device) are key-entered into the RF controller to automatically calculate the power level required for treatment of the uterine cavity of the given size. By pressing the footswitch, the cavity integrity assessment cycle is initiated, and when the cavity integrity assessment test is successfully passed, the ablation cycle is then initiated by the second activation of the footswitch. The RF treatment time averages approximately 90 seconds. The system monitors the tissue impedance (resistance) to the flow of electrical current continuously and stops the procedure when the impedance of 50 ohms is achieved. Neither concomitant hysteroscopic visualization nor endometrial pretreatment is required. The automatic cavity integrity assessment system is designed to determine whether a defect or uterine perforation is present, and the device position feedback feature allows detection of inadvertent insertion of the device into a false passage. Advantages of the NovaSure device include the shortest treatment time compared to any other device, and unlike other devices, the FDA pivotal trials were performed at any time during the endometrial cycle and conducted without endometrial pretreatment with leuprolide or D&C. One disadvantage is that if overdilation of the cervix occurs, the CO2 integrity test may fail, and placement of an additional cervical tenaculum to occlude the cervix may be necessary.
Microwave Endometrial Ablation System The Microsulis Microwave Endometrial Ablation System received FDA approval in September 2003. Microwave energy desiccates the endometrium hemispherically at a fixed high frequency of 9.2 GHz. The entire unit features a touchscreen interface with an embedded microprocessor, microwave generator, and two transmission cables (microwave and data cables). Treatment consists of destroying the endometrium to a depth of 5 to 6 mm, with temperatures during treatment rising to 70°C to 80°C. In the clinical randomized trial, all patients were treated with a GnRH agonist. Strict guidelines must be followed because of the potential for injury. An integral component of the preoperative office evaluation requires transvaginal ultrasound measurement of the uterine myometrium. The myometrium must be at least 10 mm thick to use this device. If GnRH therapy is used after the baseline myometrial measurements, a repeat ultrasound must be performed at least 10 to 14 days before surgery to ensure that use of GnRH did not adversely thin the myometrium to less than 10 mm. The myometrial thickness should be recorded as a permanent component of the clinical record in the outpatient chart. On the day of surgery, after the uterus is sounded and then dilated to 9 mm, intraoperative hysteroscopy must be performed. Landmarks, including visualization of the fundus, endometrium, and tubal ostia, must confirm that there is no uterine perforation. A D&C should never be performed with microwave technology, because theoretically, it could thin the myometrium and predispose the patient to thermal injury.
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Section 7 Reproductive Surgery During the initial 5 seconds of applicator placement, the temperature rise gate (TRG) calculates intrauterine temperature increase. If the rise in temperature is normal, the procedure is continued; otherwise, the procedure is aborted spontaneously. An abnormal TRG signals possible false passage or applicator perforation. The applicator is then placed near the fundus and moved from side to side until the temperature reaches 70°C. After fundal warming occurs, treatment of the remaining uterine cavity is undertaken by a series of movements of the applicator from side to side from the cornua to midendometrial body, until the endocervix is reached. A built-in computer link allows the physician to monitor the overall treatment. Total treatment time is usually 2 to 5 minutes. Advantages of this system include brief treatment times, the highest level of amenorrhea in the intent-to-treat group in comparison with other ablation systems, and the ability to treat uterine cavities with lengths up to 14 cm.
PEARLS ●
●
●
●
Preoperative evaluation with saline sonohysterography is important to evaluate the resectability of a myoma. Hysteroscopy alone cannot determine the depth that a myoma penetrates into the myometrium. Hysteroscopic resection of pedunculated and sessile myomas larger than 3 cm in diameter should only be attempted by experienced hysteroscopic surgeons. Patients with large myomas are at increased risk for incomplete resection and repeat surgery.
●
●
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●
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●
Removal of myomas that have an intramural component greater than 50% should not be attempted by hysteroscopy. Assessment and potential preparation of the cervix with misoprostol or laminaria is important to avoid cervical trauma. Roller ball endometrial ablation is best performed after endometrial preparation with a hormonal agent or during the follicular phase. The ThermaChoice device has the longest follow-up and more cases than any other device. Pretreatment with a suction D&C was used for the FDA trial. Ultrasound guidance is required for the cryoablation device. Visualization may be impaired in obese patients. Pretreatment with leuprolide was used for the FDA trial. It is welltolerated in the office setting. The Hydro ThermAblator uses direct visualization as the hot water circulates. It is important not to overdilate the cervix because a fluid leak can cause burns. Pretreatment with leuprolide was used for the FDA trial. The NovaSure device uses bipolar radiofrequency and requires approximately 90 seconds to complete the treatment. No pretreatment was used for the FDA trial. The Microwave Endometrial Ablation System is approved for use in patients with myomas or polyps up to 3 cm and cavity size up to 14 cm. The FDA trial used pretreatment with leuprolide. Myometrial thickness needs to be assessed before the procedure to ensure that adequate thickness is available for safe use.
REFERENCES
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1. Schenk LM, Coddington CC 3rd: Laparoscopy and hysteroscopy. Obstet Gynecol Clin North Am 26:1–22, 1999. 2. Gauss CJ: Hysteroskopie. Arch Gynaekol 133:18–24, 1928. 3. Neuwirth RS: Hysteroscopy and gynecology: Past, present, and future. J Am Assoc Gynecol 8:193–198, 2001. 4. Edstrom K, Fernstrom I: The diagnostic possibilities of a modified hysteroscopic technique. Acta Obstet Gynecol Scand 79:327–330, 1970. 5. Lindemann HJ: Eine neue Untersuchungsmethode fur die Hysteroskopie. Endoscopy 4:194–197, 1971. 6. Quinones R, Alvaredo-Duran A, Aznar-Ramos R: Tubal catheterization: Application of a new technique. Am J Obstet Gynecol 114:164–169, 1972. 7. Neuwirth RS, Amin HK: Excision of submucous fibroids with hysteroscopic control. Am J Obstet Gynecol 126:95–99, 1976. 8. Daly DC, Tohan N, Walters C, Riddick DH: Hysteroscopic resection of the uterine septum in the presence of a septate cervix. Fertil Steril 39:560–563, 1983. 9. Goldrath MH, Fuller TA, Segal S: Laser photovaporization of the endometrium in the treatment of menorrhagia. Am J Obstet Gynecol 140:14–19, 1981. 10. DeCherney AH, Diamond MP, Lavy G, Polan ML: Endometrial ablation for intractable uterine bleeding: Hysteroscopic resection. Obstet Gynecol 70:668–670, 1987. 11. Vancaillie TG: Electrocoagulation of the endometrium with the ball-end resectosope. Obstet Gynecol 74:425–427, 1989. 12. Loffer FD: Complications of hysteroscopy—their cause, prevention, and correction. J Am Assoc Gynecol Laparosc 3:11–26, 1995. 13. Cooper JM, Brady RM: Intraoperative and early postoperative complications of operative hysteroscopy. Obstet Gynecol Clin North Am 27: 347–366, 2000.
14. Ahmed N, Falcone T, Tulandi T, Houle G: Anaphylactic reaction because of intrauterine 32% dextran-70 instillation. Fertil Steril 55:1014–1016, 1991. 15. Marlow JL: Media and delivery systems. Obstet Gynecol Clin North Am 22:409–422, 1995. 16. Corson SL, Brooks PG, Serden SP, et al: Effects of vasopressin administration during hysteroscopic surgery. J Reprod Med 39:419–423, 1994. 17. Bradley L, Widrich T: State-of-the-art flexible hysteroscopy for office gynecologic evaluation. J Am Assoc Gynecol Laparosc 2:263–267, 1995. 18. Nagele F, O’Connor H, Davies A, et al: 2500 outpatient diagnostic hysteroscopies. Obstet Gynecol 88:87–92, 1996. 19. Serden SP: Diagnostic hysteroscopy to evaluate the cause of abnormal uterine bleeding. Obstet Gynecol Clin North Am 27:277–286, 2000. 20. Apgar B, Dewitt D: Diagnostic hysteroscopy. Am Family Phys 46:19S–26S, 1999. 21. Perez-Medina T, Bajo-Arenas J, Salazar F, et al: Endometrial polyps and their implication in the pregnancy rates of patients undergoing intrauterine insemination: A prospective, randomized study. Hum Reprod 20:1632–1635, 2005. 22. Martin-Ondarza C, Gil-Moreno A, Torres-Cuesta L,et al: Endometrial cancer in polyps: A clinical study of 27 cases. Eur J Gynaecol Oncol 26:55–58, 2005. 23. Farquhar CM, Steiner CA: Hysterectomy rates in the United States 1990–1997. Obstet Gynecol 99:229–234, 2002. 24. Emanuel MH, Verdel MJ, Wamsteker K: A prospective comparison of transvaginal ultrasonography and diagnostic hysteroscopy in the evaluation of patients with abnormal uterine bleeding: Clinical implications. Am J Obstet Gynecol 172:547–552, 1995.
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Chapter 42 Diagnostic and Operative Hysteroscopy 25. Wamsteker K, de Kruif J: Transcervical hysteroscopic resection of submucous fibroids for abnormal uterine bleeding: Results regarding the degree of intramural extension. Obstet Gynecol 82:736–740, 1993. 26. Bradley LD, Falcone T, Magen AB: Radiographic/imaging techniques for the diagnosis of abnormal uterine bleeding. Obstet Gynecol Clin North Am 27:245–276, 2000. 27. Preutthipan S, Herabutya Y: Vaginal misoprostol for cervical priming before operative hysteroscopy: A randomized controlled trial. Obstet Gynecol 96:890–894, 2000. 28. Thomas JA, Leyland N, Durand N, Windrim RD: The use of oral misoprostol as a cervical ripening agent in operative hysteroscopy: A double-blind, placebo-controlled trial. Am J Obstet Gynecol 186:876–879, 2002. 29. Neuwirth RS: A new technique for and additional experience with hysteroscopic resection of submucous fibroids. Am J Obstet Gynecol 131:91–94, 1978. 30. Phillips DR, Nathanson HG, Milim SJ, et al: The effect of dilute vasopressin solution on blood loss during operative hysteroscopy: A randomized controlled trial. Obstet Gynecol 88:761–766, 1996.
31. Goldenberg M, Zolti M, Bider D, et al: The effect of intracervical vasopressin on the systemic absorption of glycine during hysteroscopic endometrial ablation. Obstet Gynecol 87:1025–1029, 1996. 32. Indman PD: Use of carboprost to facilitate hysteroscopic resection of submucous myomas. J Am Assoc Gynecol Laparosc 11:68–72, 2004. 33. Philipp CS, Faiz A, Dowling N, et al: Age and the prevalence of bleeding disorders in women with menorrhagia. Obstet Gynecol 105:61–66, 2005. 34. DeCherney A, Polan ML: Hysteroscopic mangement of intrauterine lesions and intractable uterine bleeding. Obstet Gynecol 61:392–397, 1983. 35. Stabinsky S, Einstein M, Breen J: Modern treatments of menorrhagia attributable to dysfunctional uterine bleeding. Obstet Gynecol Surv 54:251–262, 1999. 36. Soysal ME, Soysal SK, Vicdan K: Thermal balloon ablation in myomainduced menorrhagia under local anesthesia. Gynecol Obstet Invest 51:128–133, 2001.
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Section 7 Reproductive Surgery Chapter
43
Hysteroscopic Management of Intrauterine Adhesions and Uterine Septa Kelly Pagidas
INTRODUCTION Intrauterine adhesions and septa represent two important uterine pathologies that may result in pregnancy loss. The management of both disorders requires both insight and skill. Heinrich Fritsch first described uterine synechiae after uterine trauma following a postpartum curettage in 1894. The prevalence of uterine synechiae seems to have decreased to the point where few centers have vast experience in their surgical management. Uterine septa are usually asymptomatic and although they are relatively common, it is still not clear when surgery is necessary.
INTRAUTERINE ADHESIONS Etiology Synechiae refers to adhesions that join together body parts, and this term is commonly used as a synonym for adhesion within the uterine cavity. In 1948, Asherman was the first to describe the frequency of uterine synechiae and the etiologic symptoms associated with the condition.1 Since then, the presence of intrauterine adhesions has also commonly become known as Asherman’s syndrome.1,2 Genital tuberculosis was first described by Netter in 1956.3 The classic observations were chronic inflammation of the endometrium resulting in severe intrauterine adhesions and often complete destruction of the endometrium, also known as Netter’s syndrome. It is quite evident that the development of adhesions requires at least one, if not all, aspects of uterine trauma and local infection to occur. The main predisposing factor for its development is overzealous curettage postpartum or postabortion. Therefore, a mainstay in the prevention of adhesions is the avoidance of unnecessary curettage. Early detection of intrauterine synechiae is also a key preventive feature after intrauterine surgery, curettage, or spontaneous abortion to identify early adhesions that are filmy, thin, and easily resected with prompt adhesiolysis.4–6
Prevalence The exact incidence of uterine adhesions in women of reproductive age is not known, but it is an infrequent cause of secondary amenorrhea, infertility, and recurrent pregnancy loss. The reported incidence of intrauterine adhesions with diagnostic
hysteroscopy is only 1%, and the overall prevalence may be in the range of 1.5%.6,7 However, the prevalence of intrauterine adhesions seen in women undergoing hysterosalpingography (HSG) is reported to be 2.7%; in women with subfertility, adhesions are seen in 4% of cases.8,9 Dicker and colleagues4 also reported that previous abortion does not predispose to intrauterine adhesions in a review of 144 women; hence, the prevalence with an uncomplicated curettage is 2.1%. The incidence of Asherman’s syndrome in a select group of women especially after curettage for missed or incomplete abortion is reported in the range of 17%, but rates as high as 30% are reported in the literature, the majority of which are mild in severity.10–13 Furthermore, in at-risk women, such as those who have undergone postpartum or incomplete curettage, the rate is speculated to be even higher.14,15 The prevalence of intrauterine adhesions in women undergoing postpartum curettage or repeat curettage for a previously incomplete curettage for missed abortion or medical abortion was reported in a prospective study of 50 women and found to be present in 40%, of whom 75% had grade II to IV intrauterine adhesions as classified by the European Society of Hysteroscopy.21 In women with menstrual disorders, a statistically significant 12-fold increase in moderate to severe Asherman’s syndrome was noted. A history of prior abortion or infection during the initial surgery was associated with a mildly but not statistically significant increase in the risk of Asherman’s syndrome.
Risk Factors Risk factors that should raise the index of suspicion for the presence of intrauterine adhesions include postpartum or postabortion curettage causing menstrual disturbance.11 Friedler and colleagues11 reported on the incidence of intrauterine adhesions with one or multiple abortions. The incidence of intrauterine adhesions after one, two, or three or more abortions was 16.3%, 14%, and 32%, respectively. The severity of adhesions was higher if at least two or more abortions were documented. There was no association between the number of previous intrauterine procedures and the presence of adhesions in asymptomatic women, but significant correlation was seen in women with menstrual disorders. The presence of infection at the initial procedure increased the presence of adhesions in this study, although it failed to reach statistical significance.
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Section 7 Reproductive Surgery Pathophysiology Any intervention that destroys the endometrium may generate adhesions of the myometrium in the opposing uterine walls. The key predictive factor to intrauterine adhesions is the gravid uterus. The gestational changes noted with a gravid uterus soften the uterine wall, resulting in greater denudation of the basalis layer with surgical intervention. The basalis layer is the regenerative layer of the endometrium.16 The most common contributing factor is an overzealous postpartum or postabortion curettage. The critical timing of the development of adhesions after uterine trauma in a gravid uterus is the first 4 weeks of the puerperium. The mechanism is probably secondary to an excessive form of wound healing. Pregnancy was found to be the predisposing factor in 91% of cases, of which 66.7% were postabortion curettage, 21.5% postpartum curettage, 2% cesarean section, and only 0.6% evacuation of a molar pregnancy.16 The contribution of infection at the time of the initial intervention in the pathophysiology of this syndrome is unknown and remains controversial13,17–19 Other reported causes include genital tuberculosis and previous uterine surgery, such as myomectomy.20 The gross pathologic changes seen in the uterus can range from marginal adhesions to complete obliteration of the cavity. The adhesions can vary from markedly dense to filmy. Adjacent to intrauterine adhesions are areas of endometrial sclerosis, which is more pronounced with dense adhesions.21 A key prognostic factor in the regeneration of endometrial tissue after adhesiolysis is the presence of the endometrial basalis, which serves as the anchoring point for the formation of new endometrium. Hence, muscular adhesions carry the worst prognosis because they are devoid or deficient in the regenerative basalis layer.22 The source of intrauterine adhesions can be endometrium, myometrium, or connective tissue, each of which has distinct characteristics. The presence of adhesions within the uterine cavity can limit uterine muscle activity and endometrial perfusion, resulting in atrophy and consequently diminishing the amount of receptive endometrium available for normal implantation.23 Impairment of normal growth and development of an implanted embryo is due to the limited space available and the impaired blood supply to the embryo.22 The postulated mechanism for poor reproductive outcome or recurrent pregnancy loss in women with intrauterine adhesions includes implantation failure secondary to endometrial atrophy with defective vascularization. Scanty endometrium with a damaged blood supply results in a lack of response to estrogenic stimuli associated with the extent of the adhesions present.23,24 Adhesions can also exist near the tubal ostia and cause tubal ostia obliteration or occlusion, further hindering implantation.
Classification
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The classification systems in existence for intrauterine adhesions include those that classify according to pathologic localization or according to hysteroscopic findings that define the location and extent of uterine adhesions. In addition, a few prognostic classification systems based on menstrual pattern exist.6 The most commonly reported classification systems used include those by Valle and Sciarra,25 Donnez and Nisolle,26 the European Society for Hysteroscopy,27 March and coworkers,28 the American
Table 43-1 March Intrauterine Adhesion Classification System Grade
Finding
Minimal
< one fourth of the uterine cavity involved Thin, filmy adhesions Fundus and ostia are clear of adhesions
Moderate
One fourth to three fourths of the uterine cavity involved No agglutination of uterine walls, only adhesions present Upper uterine cavity and ostial areas only partially occluded
Severe
> three fourths of the uterine cavity involved Agglutination of uterine walls or thick adhesion bands Upper uterine cavity and ostial areas totally occluded
From March CM, Israel R, March AD: Hysteroscopic management of intrauterine adhesions. Am J Obstet Gynecol 130:653–657, 1978.
Society for Reproductive Medicine (ASRM; formerly the American Fertility Society ),29 and Nasr and coworkers.30 The only two classification systems that include menstrual pattern as a prognostic factor are the ASRM and Nasr classification systems.29,30 The potential value of including in the classification system the presence or absence of menstrual abnormalities may be indicative of the amount of endometrium available for regeneration after adhesiolysis and may be of prognostic significance. Intrauterine adhesions at the time of hysteroscopy have been classified by March and colleagues28 into three categories as mild, moderate, and severe (Table 43-1). Briefly, adhesions can be characterized either by multiple avascular strands of fibrous tissue between the anterior and posterior uterine walls, vascularized and dense adhesions that contain inactive endometrium or myometrium or muscular adhesions where there is no notable endometrial basalis. March Classification
Intrauterine adhesions can be further characterized based on the extent of uterine involvement.28 Minimal adhesions are said to be present if less than one fourth of the uterine cavity is involved, the adhesions are thin and filmy, and the fundal and ostia areas are minimally involved or devoid of any adhesions. Moderate adhesions involve one fourth to three fourths of the uterine cavity; no agglutination of the uterine wall is seen, only adhesions are present, and the tubal ostia and fundus are only partially occluded. Severe adhesions involve more than three fourths of the uterine cavity, with agglutination of the uterine walls or thick bands with occlusions of the tubal ostia and the upper uterine cavity. The March classification system is simple and easy to apply, but it is not prognostic.28 The most accurate classification system used that describes the adhesion site and density is the European Society for Hysteroscopy system, but it is very difficult to apply or utilize clinically.27 American Society for Reproductive Medicine Classification
According to the 1988 ASRM classification system, synechiae are classified in three stages, with stage III being complete obliteration of the uterine cavity (Table 43-2).11 The ASRM classification system provides both an indirect and direct grading of intrauterine adhesions with HSG and hysteroscopy,
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Chapter 43 Hysteroscopic Management of Intrauterine Adhesions and Uterine Septa Table 43-2 American Fertility Society Intrauterine Adhesions Classification System Extent of cavity involved
< one third 1
One third to two thirds 2
> two thirds 4
Type of adhesions
Filmy 1
Filmy & Dense 2
Dense 4
Menstrual pattern
Normal 0
Hypomenorrhea 2
Amenorrhea 4
Prognostic Classification
HSG* Score
Stage I (Mild)
1–4
Stage II (Moderate)
5–8
Stage III (Severe)
9–12
Hysteroscopy Score
*All adhesions should be considered dense American Fertility Society: The American Fertility Society classification of adnexal adhesions, distal tubal occlusion, tubal occlusion, secondary to tubal ligation, tubal pregnancies, müllerian anomalies, and intrauterine adhesions. Fertil Steril 49:944–955, 1988.
respectively. The location of the adhesions is presumed to be prognostic for reproductive outcome given that most implantation occurs in the top fundal portion of the uterine cavity, and cornual adhesions may cause tubal obstruction. In addition, unlike the March classification system the significance of endometrial sclerosis or atrophy is included in the ASRM system by ascertaining the menstrual pattern. However, the ASRM classification system requires HSG to stage the adhesions, a procedure that is not routinely performed to diagnose the presence of intrauterine adhesions due to advances in ultrasonographic imaging and hysteroscopic techniques. The adoption of a uniform system of intrauterine adhesion classification is truly warranted to capture both the extent of adhesions present as well as to correlate the severity to reproductive outcome. The ability to compare existing studies and apply the knowledge to the general population hinges on the accurate and uniform description of the disease to be uniformly adopted.
Clinical Manifestations The most common presentation of intrauterine adhesions is a menstrual disturbance or reproductive disturbance (infertility and recurrent pregnancy loss). If conception occurs, it may be complicated by preterm labor or abnormal placentation, such as placenta previa or placenta accreta. Menstrual disturbances are most often categorized by amenorrhea, hypomenorrhea, or oligomenorrhea, but adhesions can also be seen in eumenorrheic women. The most common single presentation is infertility, representing 43% of reported cases; second is amenorrhea, representing 37% of cases.31 The rate of abnormal placentation, although elevated in women with intrauterine adhesions, is the least common presentation reported in women with intrauterine adhesions.
diagnostic tool used for the diagnosis of intrauterine adhesions; however, with the advances in sonographic imaging techniques, it is no longer routinely done. An HSG is no longer considered as important a screening procedure for the detection of adhesions because of its high false-positive rate and the inability to determine with certainty the extent nor severity of adhesions. Alternative methods of uterine imaging have been advocated, such as sonography and hysteroscopy. Transvaginal sonography has replaced transabdominal sonography as an imaging tool for detection of uterine pathology.32 Transvaginal ultrasonography (TVUS) was assessed in 200 patients being investigated for infertility. The overall sensitivity in the detection of endometrial pathology was 98.9%, with a positive predictive value of 94.3% and false-positive rate of 5.5%.32 The overall specificity of TVUS for normal findings was 31.3% and the negative predictive value was 71.4%; however, these data were limited given the small number of patients with normal findings reported. In this study the positive predictive value for the detection of intrauterine adhesions was 98.5%.32 The sonogram was performed in the periovulatory phase of the menstrual cycle. Another report assessed the predictive value of TVUS in 74 infertile women undergoing diagnostic hysteroscopy. The sensitivity, specificity, and positive and negative predictive value for the specific diagnosis of intrauterine adhesions were 80%, 100%, 100%, and 97%, respectively.33 However, in a separate series TVUS was unable to detect any of the cases of intrauterine adhesions, with three false-positive diagnoses,34 resulting in a sensitivity and positive predictive value of 0%. These conflicting reports could be due to technique, especially variation in the time in the cycle when the scan was performed. The poor result of TVUS in some centers has been improved with the introduction of saline infusion sonohysterography, also referred to as sonohysterography. Sonohysterography is performed with TVUS and can further enhance the detection of intrauterine adhesions. Saline solution serves as a homogeneous, echo-free contrast medium, enabling better visualization of the uterine cavity than TVUS alone. Alborzi and colleagues34 published the largest series to date to evaluate the diagnostic accuracy of HSG and sonohysterography compared to laparoscopy and hysteroscopy as the gold standard. The prospective study reviewed 86 women with infertility. In this study sonohysterography had a high diagnostic accuracy for the detection of Asherman’s syndrome, greater than that for HSG, with a sensitivity of 76.8%, a specificity of 100%, a positive predictive value of 100%, and a negative predictive value of 97.7%. In a separate study both HSG and sonohysterography had similar diagnostic accuracy.36 Sensitivity of both studies was 75%; HSG had a positive predictive value of 43% and sonohysterography had a positive predictive value of 50%. The negative predictive value of both studies was close to 100%.35 The use of magnetic resonance imaging (MRI) in the diagnosis of intrauterine adhesions remains to be elucidated.36
Technique Diagnosis Radiologic Imaging
The diagnosis of intrauterine adhesions historically has been performed through HSG and hysteroscopy. HSG was the main
Transvaginal ultrasound should be performed in the late follicular or early luteal phase of the cycle (cycle day 7, 14, or 21) using a real-time sector transvaginal probe with imaging frequencies of 5 and 7.5 MHz. In fact, the periovulatory phase is the best time
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Section 7 Reproductive Surgery to evaluate the uterine cavity contours because the endometrium is thick enough to appear more echogenic than the myometrium and not too thick to obscure the midline echo. The classic appearance of the three-layer endometrium enables better imaging of uterine defects than the postmenstrual endometrium, which is thin, less than 3 mm. The contour of the endometrial cavity is inspected for both irregularities and echo pattern of the myometrium–endometrium interphase in the sagittal (long axis) and transverse plane. The diagnostic criteria used for the diagnosis of intrauterine adhesions is interruption in the midline echo in the periovulatory phase of the cycle. The typical appearance is focal, hyperechoic, irregular, often cordlike structures seen within the echo-free space between the basalis layers, which interrupt the continuity of the endometrial cavity. These structures can vary in size from 2 to 6 mm or in location within the cavity.33
Hysteroscopy Diagnostic hysteroscopy using a 3- or 5.5-mm hysteroscope with the use of saline or CO2 can be performed safely as an office procedure with minimal analgesia and is the gold standard for the diagnosis of intrauterine adhesions, with demonstrated superiority to sonohysterography or HSG, specifically in falsepositive rates. Both radiologic techniques have high false-positive rates. Hysteroscopy is used to correctly classify intrauterine adhesions and assess them by location, shape, size, and nature.
Surgical Treatment Historical and Uncommonly Used Techniques
The classic blind dilation and curettage has gradually been abandoned in favor of the hysteroscopic approach for intrauterine adhesiolysis.16,22,25,37,38 Hysteroscopy can be performed in an outpatient setting and allows both the determination of the extent of adhesions under direct visualization and prompt treatment concurrently. A number of studies report resection of intrauterine adhesions by hysterotomy. In a review of 31 cases in 12 published studies, only 16 patients (52%) conceived, of which 8 resulted in live births, and 4 patients required a cesarean hysterectomy secondary to placenta accreta.16 Operative hysteroscopy has replaced dilation and curettage or blind dissection in the treatment of intrauterine adhesions and is the treatment of choice.16,22,25,37,38 Hysteroscopic Surgery
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The mainstays of treatment for intrauterine adhesions are early detection and prompt surgical treatment to minimize further complications. Hysteroscopy has become not only an accurate tool for the diagnosis of adhesions, but also the main method for their treatment. Hysteroscopic lysis of adhesions is indicated when the extent of adhesions is moderate to severe or access to tubal ostia is blocked. The significance of mild adhesions is still controversial, yet surgical treatment may be considered if all other causes of infertility or recurrent pregnancy loss have been excluded or successfully corrected with persistent reproductive failure. It also appears prudent to restore the uterine cavity to normal before assisted reproductive technology (ART) treatment, yet evidence remains sparse.4 An additional use, albeit with limited data, is the treatment of intrauterine adhesions secondary to genital tuberculosis prior
to in vitro fertilization–embryo transfer. However, the reformation rate is reported at 100%.37 Technique
Operative hysteroscopy is performed classically under general anesthesia using either an operative hysteroscope or resectoscope. Hysteroscopic adhesiolysis can be performed under local anesthesia in an outpatient setting with or without analgesics.16 The uterine cavity is distended using nonconductive hypoosmolar solution under manometric control if electrosurgery is used. The most common solutions used are glycine (1.5%), sorbitol (2.7%), and mannitol (0.54%). The basic technique involves resection of the intrauterine adhesions by sharp or blunt dissection. Successful hysteroscopic resection can be accomplished by the use of sharp dissection using semirigid scissors, electrosurgery, or fiberoptic laser. Current techniques of operative hysteroscopy for the lysis of intrauterine adhesions include the use of both the rigid or semirigid, #7 French flexible scissors passed through the operative channel of the 5.5-mm hysteroscope or a monopolar electrosurgical system with a resectoscope. The transcervical resectoscope with continuous flow is classically used with a #27 French scope with an inner and outer sheath, 8 and 9 mm diameter, respectively. The adhesions are incised with a high-frequency resectoscopic manual electrode needle using an angled electrode, 90-degree loop. The theoretical concern with the use of electrocautery is the negative effect of thermal damage on the endometrium and myometrium with potential risk of uterine rupture with a subsequent pregnancy. If the extent of adhesiolysis is severe, the use of laparoscopy has been promoted to reduce the risk of uterine perforation.16,25,28 Reports also exist of the use of intraoperative fluoroscopic division of adhesions, but often adhesiolysis is incomplete.39 However, there is no clear advantage for the use of electrosurgery or laser over sharp adhesiolysis using hysteroscopic scissors through the operative channel of the hysteroscope. Recent reports also include the use of the coaxial bipolar electrode system in a limited number of cases for intrauterine adhesiolysis. Its efficacy and safety appear to be similar to the conventional techniques used, but further studies need to be conducted.40,41 A case report introduced the concept of hysteroscopic adhesiolysis with guidance of a laparoscopic ultrasound in a patient with infertility and intrauterine synechiae.42 A 7.5-MHz laparoscopic ultrasound transducer was introduced though a 10mm port; placing the scanning surface of the probe firmly on the uterine serosa yielded a high-quality real-time image and safe resection of the synechiae. The potential benefit over conventional transabdominal techniques includes proper localization of the hysteroscopic instruments and greater definitions of the uterine walls to minimize uterine perforation. The technique holds promise, but further studies need to be conducted before it replaces other procedures.42–44 Adhesiolysis begins inferiorly and is carried out cephalad until a panoramic view of the endometrial cavity can be obtained and the tubal ostia are seen. The initiation of the adhesiolysis is from the internal os. Filmy and central adhesions should be cut first; marginal and dense adhesions should be approached last.39 The maintenance of adequate distension is key to the successful resection of intrauterine adhesions. Valle and Sciarra25 described
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Chapter 43 Hysteroscopic Management of Intrauterine Adhesions and Uterine Septa the use of methylene blue injection through the inferior channel of the hysteroscope when it is difficult to ascertain adhesions from a normal endometrial lining. This technique may help delineate a plane of cleavage for safe adhesiolysis. Operating time for hysteroscopic adhesiolysis varies depending on the severity of adhesions present and often may require a second intervention for adequate resection. The average operating time is 30 minutes, with a range of 10 to 60 minutes. The published studies that describe the successful use of a coaxial bipolar electrode surgical system report similar results to conventional techniques.40,41,45–47 In a series of 50 patients, of which 12 were identified with uterine adhesions and the other 12 with uterine septum, septoplasty, and intrauterine adhesiolysis was successfully completed without any major complications reported.40 The use of the bipolar vaporization system was welltolerated, safe, and likely an effective alternative to the conventional hysteroscopic techniques in the treatment of intrauterine adhesions. A key advantage appears to be the small diameter of the electrodes used, which can easily be inserted through a #5 French working channel of a 5.5-mm hysteroscope, as well as the use of normal saline solution, which is associated with reduced incidence of hyponatremia. Women with severe intrauterine adhesions and complete obliteration of the uterine cavity are the most challenging surgical cases. The key to the success of treatment is in defining the correct plane of dissection without causing a uterine perforation.28 McComb and Wagner48 have described a simplified technique for women with severe Asherman’s syndrome. In a series of six women successful adhesiolysis was accomplished using a Pratt cervical dilator first. This allowed some space to start the hysteroscopy. The curved tip points laterally toward the uterine cornua aligned with the plane of the uterine corpus. The technique is performed bilaterally, thus converting the obliterated cavity in the configuration of a uterine septum. The hysteroscope is then passed to the cornua through the passage created by the dilator and resection ensues in a similar fashion as with a septum. However, even with this technique, three central uterine perforations occurred with early detection. Five of the six women conceived, but four of the five had either a preterm delivery or abnormal placentation. Although the technique holds promise given that it identifies the lateral boundaries of the uterine cavity and the scar tissue is divided, it is still a procedure with high rates of potential complications. Similar techniques have been used with the use of fluoroscopic guidance with a 16-gauge, 80-mm Tuohy needle that is introduced alongside a 5-mm hysteroscope with similar results.39 The goal is to create a passageway using either the dilator or needle with subsequent division of the adhesions under direct vision with the hysteroscopic scissors. These specialized techniques often require multiple procedures to achieve adequate adhesiolysis.39,49,50 Radiologic Techniques
Blunt disruption of adhesions using either insemination or HSG balloon catheters has also been described.51,52 Fluoroscopicguided lysis of intrauterine adhesions was originally reported by Ikeda and colleagues51 and further developed by Karande and colleagues.52 Both procedures can be performed at the time of diagnostic HSG. Karande described a small series of patients in whom in-office lysis of intrauterine adhesions under gyneco-
radiologic control using balloon tip HSG catheters or hysteroscopic scissors inserted through the main port of the catheter was performed. Successful lysis of adhesions occurred in 81.2% of the patients, but in women with moderate or severe adhesions the procedure was abandoned secondary to significant discomfort, only leading to partial resection of the adhesions. Recent reports have also described a therapeutic role of sonohysterography for the treatment of uterine adhesions. Coccia and coworkers53 described a newly developed treatment technique for intrauterine adhesions based on sonohysterography. The technique uses saline infusion under pressure lavage of the uterine cavity to mechanically disrupt adhesions. Saline solution is initially injected slowly (5 to 10 mL) and then under increasing pressure until pain is experienced by the patient, at which point the infusion is stopped. The same procedure is repeated several times until complete uterine distension is visualized with no residual interruption of the endometrial contour nor filling defects noted. Prophylactic antibiotics and an estrogen/progesterone preparation were used after the procedure. This procedure was named the PLUG method (pressure lavage under ultrasound guidance; see Chapter 30); however, generalization of the results is limited given the small sample size (7 patients) reported. The procedure was well-tolerated, not requiring local or general anesthesia; the mean duration of the procedure was 17 minutes. The technique was more efficacious for the lysis of mild adhesions. A high rate of recurrence was noted in women with moderate to severe adhesions, due to a higher rate of incomplete adhesiolysis. Menstrual cyclicity was restored in all patients, but limited data on fertility were available. Only one of the three infertile women treated had a live birth.
Postoperative Care Despite advances in the development of techniques for adhesiolysis, the two basic problems associated with poor outcome with these procedures still exist: the inability to treat extensive or severe adhesions and the lack of methods to prevent recurrence of the adhesions postoperatively. The use of intrauterine devices, Foley catheters, antibiotics, steroids, and highdose estrogen postoperatively to prevent recurrence of adhesions is still widely debated, and no consensus exists.16 Intrauterine Device
The two most commonly used regimens for the prevention of postoperative intrauterine adhesions is the placement of either a contraceptive intrauterine device (IUD) or a pediatric Foley (#8 French) catheter and the administration of sequential (not continuous) estrogen and progesterone treatment. Prophylactic and postoperative antibiotic administration is also not consistently recommended. In addition, there appears to be no value in any presuppression therapy before hysteroscopic adhesiolysis. In cases of severe Asherman’s syndrome the use of an IUD is advocated postoperatively; it remains in situ for 1 week to 1 month, depending on the severity of the disease, to minimize adhesion reformation of the resected uterine walls. Good evidence for its effectiveness is lacking. An IUD was traditionally used. However, the modern IUD, such as the copper-bearing IUD and the Progestasert, may have too small a surface area or cause too much of an inflammatory
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Section 7 Reproductive Surgery reaction to be of any benefit. The reported preference was to use the Lippes Loop IUD.16,54 The value of the IUD is to keep the raw, freshly dissected surfaces separated during the initial phase of healing in hopes of reducing the chance of adhesion reformation. Most surgeons now use a Foley catheter with an inflatable balloon to keep the freshly dissected uterine surfaces separated. The Foley catheter is inserted into the uterus posthysteroscopy and remains in situ for approximately 1 week in most circumstances. Those that do not recommend its use suggest that it may impede endometrial regeneration by the simple pressure on the uterine wall from the inflated balloon.16 A uterine balloon stent (Cook OB/GYN, Spencer, Ind.) has been developed with a balloon that is heart-shaped and flat to conform better to the uterine cavity, although no comparative data is available for this device. Schenker16 reported on 642 patients with menstrual disorders treated with an IUD; 92% regained normal menses and 8% were hypomenorrheic. Among the 405 infertile women, 55% conceived, of whom 61% had a term delivery, 25% aborted, 7% had preterm labor, and 7% had abnormal placentation (placenta accreta). In 167 women who had insertion of a Foley balloon after adhesiolysis, 47% conceived, of whom 68% had a term delivery, 8% had preterm labor, 18% aborted, and 5% had placenta accreta. Of note, in 292 women with mild intrauterine adhesions without treatment, 133 (45%) conceived, of which 30% were term, 23% preterm, 40% aborted, and 13% had placenta accreta.
Hormonal Therapy The use of conjugated estrogen with sequential progesterone for 60 days after adhesiolysis to stimulate endometrial growth and restoration and produce re-epithelialization has been advocated. No strong evidence exists to support its efficacy. Postoperatively, the typical regimen consists of administration of 1.25 mg of conjugated estrogen (days 1 to 25) and 10 mg of medroxyprogesterone acetate (days 16–25) for 1 month or estradiol valerate 4 mg daily and micronized progesterone 600 mg daily for a period of 2 months.
Prevention The use of adhesion prevention barriers has been also reported to prevent intrauterine adhesions after curettage. A recent randomized, controlled, prospective trial describes the use of a bioresorbable membrane postoperatively within the endometrial cavity in 150 women with incomplete or missed abortion with or without a history of at least one or more prior curettage. In women with no prior history of curettage who used the membrane, all were able to conceive within 8 months after adhesiolysis compared to women who did not use the membrane, in whom only 54% conceived. In women who did not conceive with a history of prior curettage and the use of the membrane, 90% were found to be adhesion-free compared to only 50% in the untreated group. Further studies are needed before its routine use is advocated.55
Complications 646
Complications after hysteroscopic adhesiolysis include all the standard risks seen with any operative hysteroscopy. However,
among the most catastrophic events, albeit rare, are late manifestations during labor, including uterine rupture. Uterine rupture in labor has also been reported after operative hysteroscopy with and without uterine perforation. The complications associated with hysteroscopic adhesiolysis can be viewed in two major categories: those intrinsic to operative hysteroscopy and those related to the technique of adhesiolysis itself. The complications related to operative hysteroscopy are reviewed in detail in Chapter 45. In summary, the reported complications seen with operative hysteroscopy include the possibility of fluid overload, perforation, and pelvic organ injury that includes thermal damage. The overall complication rate associated with hysteroscopy is reported to be 2.7%.45,56 Furthermore, the potential risk seen with the use of the electrosurgical system includes genital burns.57,58 The rate of uterine perforation during hysteroscopic surgery is less than 2% (1.6%), of which most are recognized (97%) during the procedure. The perforation risk is highest with intrauterine adhesiolysis or during hysteroscopic adhesiolysis.16,59 The risk of postoperative infectious complications is 1.42%, but the risk of early-onset endometritis is highest after lysis of synechiae compared to other hysteroscopic procedures, including uterine septa.59 Vaginal delivery is still recommended in women after hysteroscopic adhesiolysis unless extensive damage has occurred through thermal injury or a fundal perforation has occurred. Reports exist of potential catastrophic events, albeit rare, of uterine perforation with subsequent pregnancy or labor with or without uterine perforation.The risk of abnormal placentation is in the range of 8% and is speculated to be secondary to defective lamina basalis seen after adhesiolysis.60 It is recommended that pregnancy surveillance be vigilantly pursued to detect or rule out abnormal placentation as its lack of detection can lead to catastrophic events to both the mother and fetus.
Surgical Results The success of surgery can be assessed by repeat hysteroscopy or imaging or simply by the presence of withdrawal bleeding suggestive of adequate regeneration of the endometrium. Successful pregnancy outcome is also a measure of success in women trying to conceive and seems to be correlated with the severity of the intrauterine adhesions. A number of series have been published reporting the outcome of hysteroscopic treatment of intrauterine adhesions. However, randomized clinical trials are lacking. There are also few reports about women with untreated intrauterine adhesions. Schenker16 reported on 292 women with mild intrauterine adhesions without treatment, of whom 133 (45%) conceived, of which 30% were term, 23% preterm, 40% aborted, and 13% had placenta accreta. A report of 40 consecutive women with recurrent pregnancy loss (24 women) or infertility (16 women) resulting from intrauterine adhesions showed excellent surgical results with mild or moderate disease.38 Of the 40 women, 10 had mild adhesions, 20 had moderate adhesions, and 10 had severe adhesions according to the March classification system.28 Hysteroscopic adhesiolysis was performed with hysteroscopic scissors or monopolar electrosurgery. Prophylactic antibiotics were used; postoperatively, a pediatric Foley catheter was introduced and
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Chapter 43 Hysteroscopic Management of Intrauterine Adhesions and Uterine Septa estrogen was administered. In women with hypomenorrhea as the presenting complaint, 67% reported normal menstrual cycles after adhesiolysis. All women with recurrent pregnancy loss conceived after adhesiolysis; 71% of pregnancies were term or preterm with a viable pregnancy. Among the women with infertility, 62% conceived resulting in a 37.5% live birth rate. Adhesion reformation was absent or rare in women with mild or moderate adhesions, reported as 0 to 10%. However, adhesion reformation was seen in 60% of women with severe intrauterine adhesions; none of the patients with severe adhesions conceived. Only one perforation was reported in a patient with severe adhesions. Valle and Sciarra25 reviewed 81 infertile women and reported a term pregnancy rate of 81%, 66%, and 15%, respectively, in women with mild, moderate, and severe disease. Among these women with recurrent pregnancy loss the term pregnancy rate was 94%, 89%, and 65% in those with mild, moderate, and severe adhesions, respectively. The literature is unified and quite clear in that women with severe intrauterine adhesions, the reproductive outcome remains poor even after hysteroscopic adhesiolysis.25,38 In Valle and Sciarra’s series, of the 30 women with infertility and severe adhesions, 43% of women conceived, resulting in only a 10% live birth rate. Adhesion reformation rate is also strongly correlated with the extent of severity of the initial degree of adhesions, as is the reproductive outcome after hysteroscopic adhesiolysis. The recurrence rate of severe adhesions was 48.9% and decreased to 35% after repeat adhesiolysis.25 Zikopoulos and coworkers41 reported on 46 women who underwent hysteroscopic adhesiolysis either with the resectoscope or the coaxial bipolar electrical system. It is the largest series in which the coaxial bipolar system was used. Three women required a second attempt because of the presence of adhesions postoperatively and one patient required a third procedure. Restoration of menses in women with oligomenorrhea or amenorrhea was noted in 93% of the women. The overall live delivery rate after adhesiolysis was 43.5% during a mean follow-up period of 39.2 months (±4.5 months). The live birth rate among women who tried naturally was 61.9% versus 28% after in vitro fertilization. Similar pregnancy rates were noted in women who conceived naturally whether the resectoscope or the coaxial bipolar system was used. The mean time to conception in these women was 12.2 months, and all pregnancies were achieved within 2 years after adhesiolysis. The pregnancy complication rate noted was a preterm rate of 50% and hysterectomy for abnormal placentation (placenta accreta) in 2 of the 20 patients (10%). In addition, Zikopoulos and colleagues41 reviewed the literature of existing studies; they identified seven published studies in the past decade that examined delivery rates in women undergoing hysteroscopic adhesiolysis using an array of techniques. The overall delivery rate was 38.1% (48/126) among all the studies analyzed. Pabuccu and colleagues38 reported the highest success rate among women with recurrent abortion with a delivery rate of 70.8% versus women with infertility, with a 37.5% delivery rate. The overall delivery rate was similar to that reported by Siegler and Valle60 in 1988 after reviewing a series of published studies that reported on a total of 775 women, of which 302 (38.9%) achieved a term delivery. Women with adhesions secondary to genital tuberculosis carry the worse prognosis even after hysteroscopic adhesiolysis.37
In a series of 12 women undergoing 15 attempts at hysteroscopic lysis of uterine adhesions despite adequate restoration of the uterine cavity postoperatively, the reformation rate for severe adhesions was 100%, with a 25% uterine perforation rate. Women with severe intrauterine adhesions secondary to tuberculosis carry a poor prognosis; these authors recommend alternative fertility options such as surrogacy if initial attempts at surgical adhesiolysis have failed.
UTERINE SEPTA Uterine septa are commonly found in reproductive-age women. Their impact on reproductive outcome is the subject of continuing debate. This section reviews the basic principles of pathophysiology, diagnosis, and treatment.
Embryology of the Genital Ducts Congenital uterine anomalies can arise from essentially three general categories of müllerian developmental defects that can either be partial or complete. The three categories include major disturbances of development, formation or fusion of the müllerian ducts, resulting in either arrest of development (agenesis) of the uterovaginal primordium, failure of canalization, failure of fusion, or failure of resorption. A septate uterus arises from the partial or complete failure of resorption of the midline septum between the two müllerian ducts. The embryology of the female genital tract is reviewed in detail in Chapter 12. Briefly, both the Wolffian (mesonephric) and müllerian (paramesonephric) pairs of ducts coexist from 5 to 8 weeks’ gestation during the indifferent stage of development. In the absence of müllerian-inhibiting substance produced by the Sertoli cells in the developing testis, the müllerian ducts develop into the uterus, fallopian tubes, and upper vaginal fornices. The Wolffian ducts regress with the absence of androgens. Fusion of the caudal portions of the mullerian ducts form a Y shaped structure called a uterovaginal primordium. The caudal tip of the uterovaginal primordium inserts into the dorsal wall of the urogenital sinus. Fusion with subsequent canalization forms the entire reproductive tract up to the level of the hymen, a process that is initiated at 9 weeks of gestation and completed by 20 weeks.61 The classic unidirectional theory of fusion of the müllerian ducts, caudad to cephalad, has been challenged given the existence of müllerian defects that cannot be explained by the classical unidirectional theory. These types of anomalies are incompatible with the theory of linear caudad to cephalad müllerian fusion, as described by Crosby and Hill in 1962.62 The basis of the theory was that uterine development results from fusion of the müllerian ducts during the 11th to 13th week of embryonic life, beginning at the caudal-most aspect, known as the müllerian tubercle, and proceeding in a cranial direction. Septal resorption was thought to follow shortly thereafter, beginning at any point of fusion and moving in either or both directions. An alternative theory of progression was proposed by Musset and colleagues63 and Muller and colleagues,64 in which the medial aspect of the müllerian ducts begin to fuse in the middle and proceed in both the cephalad and caudal directions simultaneously. It is then followed by rapid cellular proliferation
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Section 7 Reproductive Surgery between the ducts, forming the uterine corpus and cervix, and septal resorption, all of which occur in both directions simultaneously. The medial portion of the müllerian ducts fuses between the urogenital sinus and the isthmus of the uterus approximately in the 10th week of embryologic life and proceeds simultaneously both in the cephalad and caudad direction; a thick septum forms at the uterine fundus by the 13th week of gestation. Septal resorption, which begins in the isthmic portion and proceeds simultaneously in both directions, takes place between 13 and 20 weeks’ gestation. Failure of fusion of the müllerian ducts occurs by 10 weeks’ gestation and failure of resorption by 20 weeks.
Etiology The etiology of a septate uterus remains to be elucidated. Sporadic case reports on family pedigrees suggest familial aggregation exists, but no clear genetic cause has been linked to the development of a septate uterus.65–67 The few studies that exist report not only affected siblings, but also vertical transmission with affected mothers and daughters with similar müllerian defects. A number of genes and their interaction with environmental factors likely play a role in the development of a septate uterus, yet the true etiology is unknown.68 In general, 92% of women with congenital uterine anomalies have a normal karyotype, 46,XX; approximately 8% of women have an abnormal karyotype.69 In rare cases, early in utero exposure to radiation, infection such as rubella, and teratogens (diethylstilbestrol, thalidomide) has been implicated as the causal factor of the uterine anomaly. Furthermore, müllerian anomalies can coexist with anomalies in other organ systems, particularly in the genitourinary tract, but these are infrequently seen with a septate uterus. Hence, a complete diagnostic workup of all organ systems possibly involved in müllerian anomalies is prudent, based on the type of uterine abnormality present.
Classification
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A number of classification systems have been reported for müllerian anomalies. A single classification system needs to be uniformly adopted to allow the proper classification of patients and the ability to compare data from both national and international publications using the same system. Buttram and Gibbons70 devised a classification system of müllerian anomalies based on six groups of abnormalities. The ASRM in 1988 incorporated and revised Buttram’s classification system based on the major uterine anatomic types in existence (Table 43-3).29 The classification system proposed by the ASRM in 1988 is most commonly used to describe or define müllerian defects. The classification system organizes the anomalies into six major uterine anatomic types or categories. Two basic categories of uterine anomalies exist secondary to partial or complete failure of resorption of the müllerian ducts, classified as type V or VI. A septate uterus is among the vertical fusion defects described by the ASRM classification system. It is classified as type V; type Va is a complete septate uterus and type Vb is a partial septate uterus (see Fig. 12-3 in this book). Type VI is an arcuate uterus in the ASRM classification (see Fig. 12-3).29 The ASRM classifies an arcuate uterus into a separate category, but an arcuate uterus could be classified as a form of partial septate uterus, given that it is externally unified
and has the same embryologic origin as a septate uterus (i.e., failure of resorption of the midline septum). The basic rationale of the ASRM for placing the arcuate uterus in a separate category was the hypothesis that an arcuate uterus behaves benignly and surgical treatment is often not indicated.29 Hence, an arcuate uterus can often be classified as a septate uterus with a small septum and minimal fundal indentation (dimple). A septate uterus is characterized by a smooth, external uterine fundal contour with two uterine cavities. The extent of the septum or the degree of septation can vary from a small midline septum to total failure of resorption, resulting in a complete septate uterus with a longitudinal vaginal septum. Associated anomalies in the cervix and vagina can exist but are currently not part of the standardized ASRM classification system nor are they compatible with the unidirectional theory of müllerian development. The ASRM classification system is the most widely accepted and used by most authors and clinicians; however, a revised system that would incorporate newly described uterine anomalies that do not fit the current system would be beneficial. Such abnormalities are currently reported as isolated cases. The advent of MRI has further characterized and confirmed the presence of a complete uterine septum, dual cervices, and longitudinal vaginal septum; these anomalies do not fit the classification system used by Buttram and Gibbons.70 Case reports document the presence of a double cervix and vagina with a septate uterus.71–73 This anomaly is classified by Toaff and coworkers72 as a type 1A; this further supports Musset’s theory of müllerian development,63 which is further advocated by McBean and Brumsted.73
Incidence The true incidence of congenital uterine anomalies in the general population remains unknown, with variations in the reported incidence from study to study. The difficulty in trying to ascertain the true incidence of uterine anomalies lies primarily with the asymptomatic nature of most anomalies. However, recent
Table 43-3 ASRM Classification of Müllerian Anomalies I. Hypoplasia/Agenesis a. Vaginal b. Cervical c. Fundal d. Tubal e. Combined II. Unicornuate a. Communicating b. Noncommunicating c. No cavity d. No horn III. Didelphus IV. Bicornuate a. Complete b. Partial V. Septate a. Complete b. Partial VI. Arcuate VII. DES-related
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Chapter 43 Hysteroscopic Management of Intrauterine Adhesions and Uterine Septa improvements in uterine imaging techniques have increased their detection. The reported incidence of müllerian or uterine anomalies is between 0.5% and 6% of reproductive-age women and is highest among women with poor reproductive outcome. The estimated prevalence of uterine anomalies in all women is 2% to 3%.74–76 A review of a series of 679 women who underwent surgical sterilization by laparoscopy or laparotomy with a history of normal reproductive outcome demonstrated an incidence of uterine anomalies of 3.2%, of which 90% were septate uteri, 5% bicornuate, and 5% didelphic.75 In another review of a similar group of 323 women with normal reproductive outcome undergoing hysteroscopic sterilization, the reported incidence was 6%.76 The uterine anomalies were primarily septate or bicornuate uterus. Similar results have been reported by others.77 In a prospective study of 336 patients undergoing hysteroscopy for the evaluation of infertility, müllerian defects were noted in 5.4%, a rate similar to that reported in the general population. In contrast, a series of 228 women with uterine anomalies noted a 9.1% frequency of infertility that could be explained by other causes.78 The most common uterine abnormality seen in women with poor reproductive outcome is either a septate or bicornuate uterus, with an equal distribution in prevalence of both types of abnormalities. The overall incidence of mullerian defects reported in a series by Acien74 was 5% among women with normal reproductive history, 3% among infertile women, 5% to 10% among women with first-trimester recurrent miscarriage, and greater than 25% in women with late first- or early second-trimester loss or preterm delivery. Patients with an arcuate uterus were excluded in this incidence report. Combining a large group of infertile and fertile women from several studies, the most frequent to least frequent anomaly is bicornuate uterus, arcuate uterus, incomplete uterine septum, uterus didelphys, complete uterine septum, and unicornuate uterus.74 In this combined series of women, a bicornuate uterus and a complete or partial septum, which included an arcuate uterus, represented 74% of the uterine anomalies, equally divided between the two groups. In a summary of five major studies available in the literature that reported on 2992 cases with uterine anomalies, the overall mean incidence of uterine malformation in the general population of fertile women was 4.3%.79 After excluding earlier prevalence studies in which a septate uterus was often misdiagnosed as bicornuate due to the limitations of the imaging techniques, the frequency distribution in 1392 cases was arcuate uterus, 18.3%; septate uterus, 34.9%; and bicornuate uterus, 26%; with unicornuate uterus, didelphys uterus, and müllerian agenesis representing the rest. Hence, approximately one third of the cases were a septate uterus, which can be successfully treated hysteroscopically. This report further subdivided the incidence of müllerian anomalies in women with infertility and recurrent pregnancy loss.79 In women with infertility, depending on the study reviewed, the incidence varies between 1% and 26%. In reviewing a total of 3640 cases from existing studies, the overall mean incidence of mullerian defects in infertility patients was 3.4% which is similar to that noted in the general population (4.3%), suggesting that the septate uterus has no impact on fertility. The key presentation in women with a septate uterus is difficulty in maintaining a pregnancy and not a decreased ability
to conceive (infertility). In women with recurrent pregnancy loss, this same review reported a mean overall incidence of 12.6%, a rate higher than reported for the general population and infertile women.79 A higher incidence was seen in women with late abortion and preterm delivery than in women with earlier abortions. In women with recurrent pregnancy loss, the relative frequency of a septate versus bicornuate uterus is less clear. This lack of clarity is often attributed to old surgical data that often did not definitely differentiate a septate from a bicornuate uterus. In one of the largest studies of patients with recurrent pregnancy loss evaluated with either laparoscopy or sonohysterography, the septate uterus was more prevalent in women with recurrent pregnancy loss than the controls.80 Several case series have demonstrated that the septate uterus is more prevalent than bicornuate uterus in women with recurrent pregnancy loss.81,82 In a review of 35 women with recurrent pregnancy loss suspected of either a bicornuate or septate uterus on uterine imaging or office hysteroscopy, operative hysteroscopy and laparoscopy confirmed that all the women had a septate rather than a bicornuate uterus. In conclusion, the septate uterus is the most likely anomaly in patients with recurrent pregnancy loss.
Pathophysiology The presence of a septate uterus is thought to impair normal reproductive performance by increasing the risk or incidence of early and late abortion, preterm delivery, and the rate of obstetric complications. In a case series of women with uncorrected uterine anomalies, it was observed that 48% with septate uterus had a term pregnancy and 15% had preterm labor compared to 39% and 21%, respectively, in women with bicornuate uterus.83 The fetal survival rate was high in both groups (50% to 60%). In a separate report, first-trimester spontaneous abortions were associated with a septate uterus but not a bicornuate uterus. Definitive evidence is lacking linking infertility with uterine anomalies. The ability to conceive does not appear to be impaired in women with a septate uterus. The data does support the concept that a uterine septum imparts an elevated risk of recurrent pregnancy loss. Women with uncorrected uterine septa may experience an elevated risk of spontaneous abortion in the first or second trimester, and less commonly premature birth and abnormal fetal presentation.83,84 Yet, the association between a uterine septa and pregnancy loss is not clear and data are contradictory. In a case series of women with unexplained infertility, the spontaneous abortion rate was 22% in women with septate uterus, compared to approximately 35% in women with bicornuate or unicornuate uterus.85 The risk of pregnancy loss in women in whom the uterine septum is only an incidental finding during an evaluation for infertility is unclear.86,87 The pathogenesis of pregnancy complications in women with a septate uterus has not been completely elucidated. The most widely accepted causal theory includes the inadequate vascularization of the fibroelastic septum and altered relations between the myometrial and endometrial vessels, thus exerting negative effect on fetal placentation. The septum is primarily composed of avascular, fibromuscular tissue. Hence, it has been proposed that the endometrium lining the septum responds poorly to estrogen, resulting in irregular
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Section 7 Reproductive Surgery differentiation and estrogenic maturation.23,88–90 Implantation on this poorly vascularized, fibrous septum leads to abnormal implantation, defective embryonic development, and subsequent abortion.87,91,92 The diminished size of the uterine cavity may have also have a role in the pathogenesis of pregnancy loss. There appears to be a higher risk of poor obstetrical outcome with longer septa. Smaller septa that involve less than half of the uterine cavity are less likely to cause recurrent pregnancy loss. A smaller septum, defined as a septal length less than half of the length of the uterus, was less likely to cause recurrent pregnancy loss than larger septa; however, smaller septa are still associated with recurrent pregnancy loss.93
Diagnosis Radiologic Imaging
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Improvements in diagnostic uterine imaging techniques have now enabled a more accurate detection of the type of uterine anomaly present, which can accurately differentiate between a septate and bicornuate or arcuate uterus. Uterine imaging techniques used as a method of detection of uterine anomalies include HSG, TVUS with or without three-or four-dimensional technology, saline infusion sonohysterosonography, and MRI. Hysterosalpingography is the most commonly used diagnostic radiologic technique to determine congenital or acquired uterine defects and tubal patency. HSG is performed between the 5th and 12th day of the menstrual cycle. The diagnosis of a septate uterus is generally suspected by an HSG but often misdiagnosed.94 HSG is a simple, safe, relatively noninvasive radiologic procedure performed under fluoroscopic guidance that enables visualization of the uterine cavity, but it is limited in its ability to differentiate between a septate and bicornuate uterus (see Chapter 29). Consequently, the limitations of the HSG require additional evaluation of the external uterine contour or configuration with either surgical intervention or more recently with ultrasonography or MRI for a definitive diagnosis. Hysterosalpingography is a useful screening test and should be the first step in the evaluation of the uterine cavity. The gold standard for the accurate and proper classification for the diagnosis of a uterine anomaly has been laparoscopy and hysteroscopy, especially in women in whom the fundal contour of the uterus needs to be confirmed. Prophylactic antibiotics before the procedure are recommended in high-risk patients (e.g., those with a history of pelvic inflammatory disease or cardiac disease). The most commonly used antibiotic is doxycycline. Sedation is not routinely required because the procedure is associated with mild discomfort that is relieved by an anti-inflammatory agent given 30 to 60 minutes before the procedure. Details of this procedure are given in Chapter 29. In one study, 26 of 336 infertile women who underwent a workup for infertility with both an HSG and hysteroscopy had a diagnosis of a müllerian anomaly. Eighteen of the 26 had a confirmation of the müllerian defect seen on HSG.95 Other studies have demonstrated similar findings; however, the sensitivity and positive predictive value is highly dependent on the type of uterine malformation in question.96,97 Ultrasonography, either abdominal or vaginal, is an excellent method for the evaluation of women suspected of a septate uterus because of its low cost, noninvasiveness, and ease of performance. In addition, its portability allows intraoperative
Figure 43-1 Classic ultrasound image of myometrial echo dividing the fundal endometrial image.
imaging. TVUS is superior to transabdominal sonography in the diagnosis of a septate uterus. A real-time mechanical sector transvaginal probe is used with imaging frequency of 5 MHz and 7.5 MHz. The presence of a uterine septum is best diagnosed with a TVUS in the transverse plane. The classic findings include myometrial echoes dividing the fundal endometrial image (Fig. 43-1). The added technique of both three- and four-dimensional ultrasound may prove to be more efficacious in the diagnosis of uterine septum, but currently no clear benefit over standard TVUS has been demonstrated. A sonohysterogram has some advantages over the traditional TVUS for the diagnosis of uterine defects. This procedure is performed using a conventional transvaginal ultrasound transducer with a frequency of 5 MHz, a uterine injector with or without a balloon tip, and physiologic saline solution. The saline solution is slowly infused to achieve adequate uterine distension and the cavity evaluated in both the transverse and longitudinal plane for any defects. The procedure takes on average 5 to 10 minutes to perform in experienced hands. Neither analgesia nor sedation is routinely required because the procedure is associated with minimal discomfort. The risk of major complications after sonohysterography is similar to that seen with an HSG and is reported in the range of 1% to 2%, primarily secondary to pelvic inflammatory disease.97–99 Details of this procedure are given in Chapter 30. In one study the correlation between preoperative TVUS and hysteroscopic findings in 200 infertile women was reported.32 The overall positive predictive value of TVUS in detecting endometrial pathology was 94.3%, the sensitivity was 98.9% and the false-positive rate was 5.5%. The positive predictive value for the detection of a uterine abnormality with the use of TVUS was highest for intrauterine septa, at 100%. In a series of 65 infertile women, the diagnostic accuracy for all imaging techniques was compared to hysteroscopy.97 Both TVUS and sonohysterography had a 0% false-positive rate with a specificity and positive predictive value of 100%. In contrast HSG had a 96.4% specificity and a 66.7% positive predictive
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Chapter 43 Hysteroscopic Management of Intrauterine Adhesions and Uterine Septa value. The sensitivity of sonohysterography was 77.8% compared to 44.4% for both HSG and TVUS. These data suggest that sonohysterography can replace an HSG as the primary method for the detection of uterine septum. In another, larger case series of 86 women, the diagnostic accuracy of HSG and sonohysterography was compared to laparoscopy and hysteroscopy.34 The use of sonohysterography for uterine anomalies had a sensitivity of 94%, a specificity of 100%, a positive predictive value of 100%, and a negative predictive value of 96.2%. These data are similar to those of the previous study,97 but they had less favorable results; the major limitation of sonohysterography was with the detection of an arcuate uterus. Magnetic resonance imaging can accurately predict the presence of uterine anomalies and has become the imaging method of choice to confirm inconclusive results from other methods. A number of recent reports describe the effective use of MRI in the evaluation of uterine anomalies.71,100–103 MRI is both sensitive and specific in differentiating between the types of uterine anomalies present, including the arcuate uterus. The clear advantages of an MRI include the ability to distinguish between myometrial and endometrial tissue, image the uterus in several planes, and define uterine contour.100,104–106 The MRI can accurately detect the fundal contour to include measuring the intercornual diameter, which is required to differentiate a bicornuate from a septate uterus. A septate uterus is defined by a smooth fundal contour with an intercornual diameter of less than 4 cm. In addition, Fedele and coworkers100 remarked that a fundal indentation of less than 10 mm and an angle between the medial margins of the hemicavities of less than 60 degrees seen on MRI differentiates a septate from a bicornuate uterus. Similar findings were reported by others71 (see Chapter 31). Furthermore, the uterine septum can be further characterized by the presence or absence of myometrial tissue and vascularization of the septum versus only a fibrous consistency throughout its entire length seen with a septum. The positive predictive value for MRI for the detection of uterine septum has been reported as high as 100%.106 Several studies have reported correct diagnosis of uterine anomalies in 100% of cases when using MRI as an adjunct to surgery.100,101 In a separate review of 23 cases of müllerian anomalies, the correct diagnosis was made in 96% of cases with MRI, compared to 85% for TVUS.102 Another advantage of MRI is its ability to detect the associated anomalies in other organ systems typically seen with müllerian anomalies, such as renal or urinary tract anomalies.106 The major disadvantages include the lack of portability and higher costs compared with other imaging modalities. Laparoscopy and hysteroscopy together have been traditionally used to detect and characterize uterine septums. In a prospective, randomized study the authors106 found no significant difference between hysteroscopy, saline infusion hysterosonography, and HSG in the evaluation of uterine cavity in infertile women. The main limitation of hysteroscopy is the inability to determine the contour of the uterus and therefore definitively differentiate between uterine anomalies such as a bicornuate or septate uterus. The classic findings at the time of surgery to diagnosis a septate uterus include a convex, flat, smooth, or minimally depressed (1 cm or less) external fundal contour. The presence of a split uterine cavity can be confirmed by intraoperative
sonographic imaging or by hysteroscopy. Laparoscopy is now reserved for the confirmation of a septate uterus before resection if there is an inconclusive imaging.
Surgical Treatment Historical Perspective
The goal of surgical repair of a uterine septum is restoration of a normal uterine cavity. However, normal surgical restoration of the uterine cavity does not necessarily imply good reproductive prognosis because uterine vascularization may also be impaired. Ruge reported the first documented case of surgical removal of a uterine septum in 1884. The removal of the uterine septum was accomplished by transcervical resection. This technique was then abandoned in favor of abdominal procedures. In 1907, Strassman described the abdominal metroplasty. It was the surgical technique of choice for unification of the uterine horns in bicornuate and didelphic uteri. Jones and Jones108 and Tompkins109 in 1953 and 1962, respectively, made further modifications to the technique of abdominal metroplasty. Despite the achievement of excellent outcomes with abdominal metroplasty, there were sufficient major disadvantages associated with the technique that have rendered these procedures obsolete.110,111 The disadvantages include risk of hemorrhage, significant pelvic adhesions, prolonged postoperative recovery with associated high morbidity, and the need for operative delivery (cesarean section) if pregnancy is achieved.108,109 With advances in operative hysteroscopic techniques, transcervical resection of a uterine septum was reintroduced as an outpatient procedure. Hysteroscopic metroplasty is the method of choice, with benefits that include lower morbidity, faster recovery, and lower risk of infection, hemorrhage, and adhesions. In addition, most cases avoid abdominal and myometrial incisions, hence not requiring operative delivery in uncomplicated cases. Women can also attempt pregnancy 2 months after resection versus 3 to 6 months with abdominal metroplasty. Operative hysteroscopic metroplasty is now the accepted surgical technique for the treatment of uterine septum.112,113 Indications
The most common and accepted indication for surgical resection of uterine septum is recurrent first- or early second-trimester pregnancy loss. The simple presence of primary infertility without pregnancy loss is a controversial indication for surgical repair. The impact of a septate uterus on assisted reproductive technology procedures is not well defined. It remains controversial whether or not surgical resection of a uterine septum before the occurrence of a reproductive loss is beneficial given the well-documented evidence that patients with septate uterus can have uncomplicated pregnancy. The true risk of initial or subsequent miscarriage rates or poor reproductive outcomes is not known, hence making proper counseling of patients with septate uterus difficult as a prophylactic measure. Most studies would support the observation that primary infertility in the presence of a septate uterus is not an indication for hysteroscopic metroplasty, but the procedure may be considered after appropriate evaluation and treatment of other causes of infertility fails. Furthermore, the simplicity and low morbidity of hysteroscopic metroplasty has led many experts to recommend removal, especially in older women.
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Section 7 Reproductive Surgery Limited data support prophylactic treatment for the prevention of poor reproductive outcome in subsequent pregnancies even if the first pregnancy is normal. Acien evaluated the pregnancy outcome in 176 patients with untreated müllerian defects.74 He reported on the pregnancy outcome with a first or subsequent pregnancy. The abortion rates were the same with the first pregnancy as with all subsequent pregnancies. However, the pregnancy outcome was worse with subsequent pregnancies than with a first pregnancy, with a lower term delivery rate and higher preterm rate. In the subgroup of 31 patients with a septate uterus, a total of 89 pregnancies were achieved. The pregnancy outcome for the first versus all subsequent pregnancies was 21% versus 23% for spontaneous abortions, 8% versus 23% for preterm delivery, and 71% versus 54% for term delivery. Hence, women with septate uterus had worse reproductive outcomes with subsequent pregnancies than with the first one. The normal uterus was associated with an 8% abortion rate, 6% preterm delivery rate, and 85% term delivery rate. Hysteroscopic Technique
Operative hysteroscopy is usually performed under general anesthesia using either an operative hysteroscope or resectoscope. The uterine cavity is distended using nonconductive hypoosmolar solution if monopolar cautery is used. If bipolar cautery is used, isotonic saline solution can be used. The most common solutions used with monopolar systems are glycine (1.5%), sorbitol (2.7%), and mannitol (0.54%); normal saline solution is
used with bipolar systems. The basic technique usually involves simple incision of the septum rather than removal or resection. However, some large broad-based septa are excised partially. Most of the large published studies on hysteroscopic metroplasty used microscissors as the method of choice for surgical resection of the septum.112–114 Two of the most common instruments used to accomplish either incision or resection of the septum are the rigid and semirigid flexible scissors (Fig. 43-2). These are #7 French instruments passed through the operative channel of the hysteroscope. Alternatively, a wire loop can be introduced through a #21 French sheath of an operative resectoscope. There are bipolar systems that use a typical operative hysteroscope; instruments are introduced through the working channel that has electrocautery capabilities for incision. The limitations with the use of scissors include more difficulty in dissecting or cutting a broad-based septum. The theoretical concern with the use of electrocautery is the negative effect of thermal damage on the endometrium and myometrium with potential risk of uterine rupture with a subsequent pregnancy. The use of the laser for hysteroscopic metroplasty has been reported with equivalent postoperative results. However, its superiority over the other techniques is unproven.115,116 A number of studies exist confirming the efficiency and safety of the use of Nd:YAG laser for hysteroscopic metroplasty.117 Similar pregnancy outcomes have been reported with conventional methods. The clear advantage of the Nd:YAG laser is the bloodless nature of the operation and rapid incision of the septum. The use of a
A
C
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Figure 43-2 septum.
B
D
E
Hysteroscopic resection of a uterine septum. Cautery or scissors can be used. It is critical that the incision plane is in the middle of the
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Chapter 43 Hysteroscopic Management of Intrauterine Adhesions and Uterine Septa flexible fibroscope and the absence of need for cervical dilation are additional advantages. However, its expense makes it prohibitive. Hysteroscopic metroplasty is performed ideally in the early follicular phase of the menstrual cycle when the endometrium is thin, hence not requiring any preparation of the endometrium. Continuous flow of fluid is used for uterine distension. Classical teaching has advocated the use of a laparoscope to visualize the transilluminated uterine fundus to assess myometrial thickness and determine optimal resection of the septum while avoiding uterine perforation. However, this is not necessary in most cases. If the loop electrode is used with the resectoscope, the setting should not exceed 100 to 120 watts for cutting current and 50 watts for coagulation. Resection of the septum with the use of a coaxial bipolar electrode surgical system is effective in normal saline solution. The bipolar instrument is passed through a #5 French operating channel of a 5.5-mm hysteroscope.45,118–120 The technique involves either vaporization or excision of the septum. The two basic modes include the vapor cut mode and the desiccation mode, with a range of power settings available (1 to 200 watts), the former being more advantageous for women with infertility. To date limited experience exists with respect to hysteroscopic metroplasty using this form of energy source, but this technique likely holds promise given the theoretical lower risk of fluid overload with normal saline solution as the distension media used and the minimized risk of electrosurgical genital burns.45,118–120 Fernandez and colleagues120 reported on 12 women undergoing septoplasty with the coaxial bipolar system with similar results to traditional surgical techniques. The coaxial bipolar electrode surgical system appears safe and well-tolerated and is likely an effective alternative to conventional hysteroscopic techniques, but further studies need to be completed. Concurrent laparoscopy and hysteroscopy has been the gold standard for resection of the septum, yet more recent data suggest that intraoperative transabdominal ultrasound can be used both safely and adequately. However, few studies exist, with limited sample size.121,122 The added advantage to the use of intraoperative transabdominal sonography during septum resection is the ability for ultrasound to determine the thickness of the uterine wall and minimize resection of the myometrium. However, there are no data that show that the use of the laparoscope or intraoperative ultrasound has better outcomes than operative hysteroscopy alone. Resection or horizontal incision of the septum is carried out from the lower margin of the septum and continued cephalad toward the tubal ostia, always staying in the midline and horizontal plane of the septum, minimizing incision into the myometrium and always staying in the most superficial myometrial fibers. One can safely assume that the base of the septum has been reached if increased bleeding is noted. The end point of resection can be characterized by a number of parameters, including visualization of pink, vascular myometrium from the white, avascular septum; the relationship of the resection to the tubal ostia; and the proximity of the resection to the uterine serosa, as noted via laparoscopy or ultrasound. A successful resection of the septum is defined when the tubal ostia are seen together with no separation in between, an enlargement of the uterine cavity is demonstrated, and an improvement in the uterine shape is accomplished. At the end of the removal of the septum, the
uterine cavity should appear normal, and the fundus should be easily visualized with the ability to sweep easily between the ostia. Regardless of which technique is used, the goal should be to reduce the septal surface area and unify the uterine cavity. The surgical technique used for a complete uterine septum includes placement of either a plastic uterine dilator or balloon HSG catheter or Foley balloon through the contralateral cervix to indent the septum wall, as well as prevent the loss of distension medium through the second cervical opening.123 The hysteroscope is then inserted in the opposite cervix and resection is initiated over the indented septum wall, enabling a safe resection. It is important to identify the point above the cervix in which the resection can be initiated. Once the passage is created, resection is then completed while sparing the cervix tissue. Limited studies exist, but the recommendation is to spare the cervical portion and preserve the septum below the internal os to minimize the risk of cervical incompetence in subsequent pregnancies.123–125 Abdominal Metroplasty
In rare cases when the septum cannot be removed via a hysteroscopic approach, abdominal metroplasty can be contemplated. However, the infrequent use of such technique makes it difficult to have skilled surgeons to perform such a procedure. The Jones metroplasty involves a wedge resection of the portion of the uterine fundus that contains the septum. A triangular incision is made in the anteroposterior plane of the uterus. The use of intramuscular vasopressin is recommended (10 units/30 mL of saline solution) to minimize bleeding once the uterine incision is made. Similar techniques as those utilized in myomectomy to reduce the amount of arterial bleeding can be performed. These include a tourniquet around the lower uterine segment to temporarily occlude the uterine artery. It is recommended first that traction sutures be placed lateral to the triangular incisions. A wedge-shaped tissue is then resected until the endometrial cavity is unified. Uterine reconstruction is then initiated from the base of the wedge and completed in three layers. The first layer includes approximation of the anterior and posterior uterine wall using either a continuous or interrupted suture while burying the knot within the uterine cavity. The first layer incorporates the endometrium and a small portion of myometrium with a 2-0 absorbable suture. The second layer includes closure of the myometrium with interrupted sutures placed deep in the myometrium. The third layer is the seromuscular layer that includes the serosa and the superficial part of the myometrium, in either a continuous or interrupted absorbable suture of 3-0. The Tompkins metroplasty, unlike the Jones procedure, does not involve resection of uterine tissue but rather a midline incision in the anteroposterior plane until the uterine cavity is visualized. The two cavities are then unroofed and closure is performed. The advantage of the Tompkins metroplasty is that the uterine cavity achieved postunification is larger given that normal uterine tissue is not removed. Radiologic Techniques
Resection of a uterine septum using radiology techniques has been described.126,127 Karande and Gleicher127 reported on 14 patients who underwent in-office resection of a uterine septum under fluoroscopic control. Resections were carried out
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Section 7 Reproductive Surgery with the technique described for intrauterine adhesions, using either hysteroscopic scissors in combination with a specially designed balloon catheter or in select cases using 2-mm microlaparoscopic scissors. Successful resection was reported in all patients with minimal complaints of major discomfort. The procedure was completed within 20 to 30 minutes, with an associated radiation exposure time of less than 7 minutes. However, no pregnancy outcomes were reported in the study. Some potential advantages appear to be the lack of need for anesthesia, the performance in an office setting, the depth perception provided with fluoroscopic control, and abolished risk of fluid overload. No direct comparative trials exist comparing radiologic resection and hysteroscopic metroplasty. Although the technique holds promise, further studies are needed and hysteroscopic metroplasty still remains the standard of care for the resection of uterine septa.
Postoperative Care A number of adhesion prevention techniques have been described after hysteroscopic metroplasty. Postoperative estrogens or intrauterine contraceptive devices have been used. However, randomized studies in women undergoing hysteroscopic resection of the uterine septum have noted no difference in the postoperative intrauterine adhesion rates with follow-up imaging either by HSG or hysteroscopy with the use of either agent.114,128,129 Furthermore, endometrial preparation with gonadotropin-releasing hormone agonists, gestogens, or danazol are not efficacious nor required because the endometrium is thin enough in the follicular phase of the cycle. In addition, the use of postoperative antibiotics is not required. Postoperative formation of intrauterine adhesions is rare, as are postoperative infections. New endometrium develops within 2 months after hysteroscopic metroplasty simply by endogenous estrogen that stimulates endometrial re-epithelization, as reported by Candiani and coworkers.130
Complications
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Hysteroscopic metroplasty is the accepted treatment for the septate uterus.112 Although it is a relatively safe procedure with documented improvement in reproductive outcome in women with recurrent pregnancy loss, it is not free of complications. The operative complications of hysteroscopy have been reported to occur in 2.7% of hysteroscopies and include uterine perforation, excessive hemorrhage, air embolus, pulmonary edema, excessive glycine absorption, and infection.87 After hysteroscopic metroplasty the uterine walls are considered strong enough to support labor. However, among the most catastrophic events are those that occur during labor, such as uterine rupture.131 Uterine rupture in labor has been reported after uncomplicated operative hysteroscopy without rupture as well as after uterine perforation during hysteroscopic metroplasty.131–137 The complications associated with hysteroscopic metroplasty can be viewed in two major categories: those intrinsic to operative hysteroscopy and those related to the technique and instruments used for septum resection. The complications related to operative hysteroscopy are reviewed in detail in Chapter 45. In summary, the reported complications seen with operative hysteroscopy include the possibility of fluid overload, perforation, and pelvic organ injury, including thermal damage if electrode surgical
systems are used. The overall complication rate associated with hysteroscopy is reported to be 2.7%.87 The distension media usually used with the monopolar electrosurgical system are sorbitol or glycine. The septum resection hence needs to be carried out in a timely fashion to minimize excessive fluid overload and the development of hyponatremia, cerebral edema, and possible death. The use of normal saline solution with either the operative hysteroscope or the bipolar electrosurgical system is associated with reduced risk of electrolyte changes and hyponatremia with excessive fluid absorption, but the risk is not abolished. Report exists of fluid overload with the use of saline solution, pulmonary edema, and brain edema.45 Furthermore, the risk potential seen with the use of the electrosurgical system includes electrosurgical genital burns, seen mostly with the use of the monopolar systems.57,58 The major concern with the use of the electrosurgical systems is uterine rupture at the actual site of the septum with a later pregnancy secondary to weakening of the uterine wall from thermal damage. The rate of uterine perforation is lower with resection of a uterine septum than it is for intrauterine adhesiolysis and is reported to be less than 1%.59 Vaginal delivery is still recommended in women after hysteroscopic metroplasty unless extensive damage has occurred through thermal injury or a fundal perforation has occurred. Reports exist of potential catastrophic events, albeit rare, including uterine perforation with subsequent pregnancy or labor. Uterine rupture has been reported with both uncomplicated hysteroscopic metroplasty, as well as after uterine perforation during hysteroscopic metroplasty. The rupture, most often fundal in location, can extend from cornua to cornua and likely is secondary to either a weakened myometrium from extensive resection of the septum into the myometrium, thermal damage from the use of the electrical system, or an undiagnosed uterine perforation.131–138 However, metroplasty may weaken the uterine wall regardless of the method used and despite the absence of perforation. Angell and colleagues136 reported a review of the literature on uterine rupture at term with or without uterine perforation. It is possible that the septate uterus is congenitally weakened; hence an inherent risk exists before metroplasty. Once uterine rupture occurs, successful outcomes by cesarean section with a subsequent pregnancy are possible.139
Outcome Many studies exist that report both presurgical and postsurgical outcome in women with hysteroscopic metroplasty. However, to date there are no published randomized clinical trials that compare pregnancy outcome in a treated and untreated group of symptomatic women. Hence, surgical outcomes after treatment of septate uterus are based on retrospective studies evaluating the reproductive outcome of women, often using patients as their own control. The overall reported rate of successful pregnancy after hysteroscopic metroplasty is 85% to 90%.78,108,113,116 In a small retrospective series of 40 women, Hickok90 reported a miscarriage rate of 77.4%, delivery rate of 22.6%, and uncomplicated delivery rate of 6.5% preoperatively compared to a miscarriage rate of 18.2%, delivery rate of 81.8%, and uncomplicated delivery rate of 77.3% postoperatively. Venturoli and coworkers140 reviewed a large series of 141 women who underwent a hysteroscopic metroplasty with a partial
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Chapter 43 Hysteroscopic Management of Intrauterine Adhesions and Uterine Septa septate uterus (class Vb, ASRM). Two groups of women were identified: Group I (69 patients) presented with primary unexplained infertility of at least 2 years’ duration and group II (72 patients) with two or more recurrent losses within 3 years and no prior deliveries. The mean age of the women was similar in both groups, and only women who wanted to conceive were included in the study. The mean postoperative follow-up period was 36 months (±19.5). The pregnancy rate postseptum resection for group I and group II was 52.1% and 52.7%, respectively; the spontaneous abortion rate was 20% and 25%, respectively. The preterm and term delivery rates were similar in groups I and II, 10% and 15.5%, respectively, for term delivery and 52.5% and 46.2%, respectively, for preterm. Kupesic141 reviewed the reproductive outcome from 13 studies in women with untreated septate uterus and reported on 1304 pregnancies with a miscarriage rate of 81.9% and a preterm delivery rate of 9.6%, but the author cautions that the group of women reviewed may represent a biased group; women may have been excluded who had a septate uterus and normal reproductive outcome. Kupesic also reported a review of the existing literature with regard to reproductive outcome before and after hysteroscopic metroplasty for septate uterus. In 388 patients, 1059 pregnancies were achieved before metroplasty and 362 pregnancies after surgery. The miscarriage rate, preterm delivery rate, and term delivery rate were 87.8%, 9.0%, and 3.2%, respectively, before metroplasty versus 14.6%, 5.2%, and 80.1%, respectively, after metroplasty. However, there still remains some debate whether metroplasty improves the outcome in women with recurrent pregnancy loss. In a series of 146 women reported by Kirk and colleagues,142 no increase in the number of living children was found after metroplasty even in women with uterine septum. Hysteroscopic metroplasty in women with recurrent pregnancy loss does not impair their fertility potential. Multiple studies report that patients with recurrent pregnancy loss and normal fertility were able to conceive at least once after hysteroscopic metroplasty. Normal monthly fecundity exists for such women.79,115,143 The chance of pregnancy was not affected by maternal age, number of previous pregnancy losses, or method of septal resection (microscissors, resectoscope, or laser) nor by the type of septum present, partial or complete.91,92
In contrast, women with infertility and septal resection appear to have lower cumulative pregnancy rates and live birth rates. This is probably related to the presence of additional infertility factors compromising the chance of pregnancy, or the possibility that presence of the septum was not the cause of the infertility.115 In women with primary infertility and a septate uterus, the data are limited as to whether there is an improvement in the pregnancy rate. The possible adverse effect of the presence of a septate uterus on the outcome of ART is still debated. The existing studies do not demonstrate any impairment in ovarian response to stimulation nor implantation rates in the presence of müllerian anomalies, including septate uterus. However, the studies do report a higher rate of abortion and preterm delivery if the septum is uncorrected.79,144,145 Although hysteroscopic metroplasty is not intended to enhance fertility, it may be indicated for the improvement of pregnancy outcome, especially after multiple failed assisted reproductive cycles.
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The incidence of adhesions after postpartum curettage or curettage after spontaneous abortion is 17%. Hysteroscopy remains the best way to both diagnose and treat intrauterine adhesions. Adhesiolysis of mild or moderate adhesions improves reproductive outcome. Adhesiolysis of severe intrauterine adhesions is less likely to improve reproductive outcome, and obstetric complications are common in those who become pregnant. The incidence of uterine septa is 2% to 3%, making it one of the most common reproductive tract anomalies. The incidence of uterine septa in infertile women is similar to its incidence in the general population. Women with recurrent pregnancy loss have a threefold increase in the incidence of uterine septa. Sonohysterography and MRI have excellent diagnostic accuracy for the detection of uterine septa and have replaced hysteroscopy as the diagnostic tool of choice. Hysteroscopic septum resection has proven to be safe and reduces the risk of recurrent pregnancy loss.
REFERENCES 1. Asherman JG: Amenorrhea traumatica. J Obstet Gynaecol Br Emp 55:23–30, 1948. 2. Asherman JG: Traumatic intrauterine adhesions. BJOG 57:892–896, 1950. 3. Netter AP, Musset R, Lambert A, Salomon Y: Traumatic uterine synechiae: A common cause of menstrual insufficiency, sterility and abortion. Am J Obstet Gynecol 71:368–375, 1956. 4. Dicker D, Ashkenazi J, Dekel A, et al:. The value of hysteroscopic evaluation in patients with preclinical in vitro fertilization abortions. Hum Reprod 11:730–731, 1996. 5. Taskin O, Sadik S, Onoglu A, et al: Role of endometrial suppression on the frequency of intrauterine adhesions after resectoscopic surgery. J Am Assoc Gynecol Laparosc 7:351–354, 2000. 6. Al-Inany H: Intrauterine adhesions. An update. Acta Obstet Gynecol Scand 80:986–993, 2001. 7. Fedorkow D, Pattinson HA, Taylor PJ: Is diagnostic hysteroscopy adhesiogenic? Int J Fertil 36:21–22, 1991.
8. Sweeney WJ: Intrauterine synechiae. Obstet Gynecol 27:284–289, 1966. 9. Sirbu P, Coman A, Vexler E: Gynecol Obstet (Paris) 56:521–528, 1957. 10. Adoni A, Palti Z, Milwidsky A: The incidence of intrauterine adhesions following spontaneous abortions. Int J Fertil 27:117–178, 1982. 11. Friedler S, Margalioth EJ, Kafka I, Yaffe H: Incidence of post-abortion intra-uterine adhesions evaluated by hysteroscopy—a prospective study. Hum Reprod 8:442–444, 1993. 12. Golan A, Schneider D, Avrech O: Hysteroscopic findings after missed abortion. Fertil Steril 58:508–510, 1992. 13. Romer T: Postabortion hysteroscopy—a method for early diagnosis of congenital and acquired intrauterine causes of abortions. Eur J Obstet Gynecol Reprod Biol 57:171–173, 1994. 14. Lurie S, Appelman Z, Katz Z: Curettage after midtrimester termination of pregnancy—is it necessary? J Reprod Med 36:786–788, 1991. 15. Westendorp ICD, Ankum WM, Mol BWJ, Vonk J: Prevalence of Asherman’s syndrome after secondary removal of placental remnants
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or a repeat curettage for incomplete abortion. Hum Reprod 13:3347–3350, 1998. Schenker JG: Etiology and therapeutic approach to synechia uteri. Eur J Obstet Gynecol Reprod Biol 65:109–113, 1996. Jensen PA, Stromme WB: Amenorrhea secondary to puerperal curettage (Asherman’s syndrome). Am J Obstet Gynecol 113:150–157, 1972. Taylor PJ, Cumming DC, Hill PJ: Significance of intrauterine adhesions detected hysteroscopically in eumenorrheic infertile women and the role of antecedent curettage in their formation. Am J Obstet Gynecol 139:239–242, 1981. Polishuk WZ, Schenker JG: Induction of intrauterine adhesions in the rabbit with autogenous fibroblast implants. Am J Obstet Gynecol 115:789–794, 1973. Yaffe H, Ron M, Polishuk WZ: Amenorrhea, hypomenorrhea and uterine fibroids. Am J Obstet Gynecol 130:599–601, 1978. Sugimoto O: Diagnostic and therapeutic hysteroscopy for traumatic intrauterine adhesions. Am J Obstet Gynecol 131:539–547, 1978. March CM: Update: Intrauterine adhesions. Fertil News XVIV, 1996. Sparac V, Kupesic S, Ilijas M, et al: Histologic architecture and vascularization of hysteroscopically excised intrauterine septa. J Am Assoc Gynecol Laparosc 8:111–116, 2001. Polishuk WZ, Siew FP, Gordon R, et al: Vascular changes in traumatic amenorrhea and hypomenorrhea. Int J Fertil 22:189–192, 1977. Valle RF, Sciarra JJ: Intrauterine adhesions: Hysteroscopic diagnosis, classification, treatment and reproductive outcome. Am J Obstet Gynecol 158:1459–1470, 1988. Donnez J, Nisolle M: Hysteroscopic lysis of intrauterine adhesions (Asherman’s syndrome). In Donnez J (ed). Atlas of Laser Operative Laparoscopy and Hysteroscopy. New York, Press-Parthenon Publishers, 1994, pp 305–322. Wamsteker K, DeBlok SJ: Diagnostic hysteroscopy: Technique and documentation. In Sutton C, Diamond M (ed). Endoscopic Surgery for the Gynecologist. New York, Lippincott Williams and Wilkins, 1995, pp 263–276. March CM, Israel R, March AD: Hysteroscopic management of intrauterine adhesions. Am J Obstet Gynecol 130:653–657, 1978. American Fertility Society: The American Fertility Society classifications of adnexal adhesions, distal tubal occlusion, tubal occlusion secondary to tubal ligation, tubal pregnancies, Müllerian anomalies, and intrauterine adhesions. Fertil Steril 49:944–955, 1988. Nasr AL, Al-Inany HG, Thabet SM, Aboulghar M: A clinicohysteroscopic scoring system of intrauterine adhesions. Gynecol Obstet Invest 50:178–181, 2000. Schenker JG, Margalioth EJ: Intrauterine adhesions. An updated appraisal. Fertil Steril 37:593–610, 1982. Narayan R, Gosway RK: Transvaginal sonography of the uterine cavity with hysteroscopic correlation in the investigation of infertility. Ultrasound Obstet Gynecol 3:129–133, 1993. Shalev J, Meizner I, Bar-Hava I, et al: Predictive value of transvaginal sonography performed before routine diagnostic hysteroscopy for evaluation of infertility. Fertil Steril 73:412–417, 2000. Alborzi S, Dehbashi S, Khodaee R: Sonohysterosalpingographic screening for infertile patients. Int J Gynecol Obstet 82:57–62, 2003. Fedele L, Bianchi S, Dorta M, Vignali M: Intrauterine adhesions: Detection with transvaginal ultrasound. Radiology 199:757–759, 1996. Bacelar AC, Wilcock D, Powell M, Worthington BS: The value of MRI in the assessment of traumatic intra-uterine adhesions (Asherman’s syndrome). Clin Radiol 50:80–83, 1995. Bukulmez O,Yarali H, Gurgan T: Total corporal synechiae due to tuberculosis carry a very poor prognosis following hysteroscopic synechialysis. Hum Reprod 14:1960–1961, 1999. Pabuccu R, Atay V, Orhon E, et al: Hysteroscopic treatment of intrauterine adhesions is safe and effective in the restoration of normal menstruation and fertility. Fertil Steril 68:1141–1143, 1997. Broome JD, Vancaillie TG: Fluoroscopically guided hysteroscopic division of adhesions in severe Asherman syndrome. Obstet Gynecol 93:1041–1043, 1999.
40. Fernandez H, Gervaise A, de Tayrac R: Operative hysteroscopy for infertility using normal saline solution and a coaxial bipolar electrode: A pilot study. Hum Reprod 15:1773–1775, 2000. 41. Zikopoulos KA, Kolibianakis AM, Plateau P, et al: Live delivery rates in sub fertile women with Asherman’s syndrome after hysteroscopic adhesiolysis using resectoscope or the Versapoint system. RBM Online 8:720–725, 2004. 42. Bulent Tiras M, Oktem M, Noyan V: Laparoscopic intracorporeal ultrasound guidance during hysteroscopic adhesiolysis. Eur J Obstet Gynecol Reprod Biol 108:80–84, 2003. 43. Goldberg BB, Liu JB, Kuhlman K, et al: Endoluminal gynecologic ultrasound: Preliminary results. J Ultrasound Med 10:583–590, 1991. 44. Goldberg BB, Liu JB, Merton DA, et al: Sonographically guided laparoscopy and mediastinoscopy using miniature catheter-based transducers. J Ultrasound Med 12:49–54, 1993. 45. Vilos GA: Intrauterine surgery using a new coaxial bipolar electrode in normal saline solution (Versa point*): A pilot study. Fertil Steril 72:740–743, 1999. 46. Lindheim SR, Kavic S, Shulman SV, Sauer MV: Operative hysteroscopy in the office setting. J Am Assoc Gynecol Laparosc 7:65–69, 2000. 47. Marwah V, Bhandari SK: Diagnostic and interventional microhysteroscopy with the use of the coaxial bipolar electrode system. Fertil Steril 79:413–417, 2003. 48. McComb PF, Wagner BL: Simplified therapy for Asherman’s syndrome. Fertil Steril 68:1047–1050, 1997. 49. Lancet M, Mass N: Concomitant hysteroscopy and hysterography in Asherman’s syndrome. Int J Fertil 26:267–272, 1981. 50. Neuwirth RS, Hussein AR, Schiffman BM, Amin HK: Hysteroscopic resection of intrauterine scars using a new technique. Obstet Gynaecol 60:111–113, 1982. 51. Ikeda T, Morita A, Imamura A, Mori I: The separation procedure for intrauterine adhesions (synechia uteri) under roentgengraphic view. Fertil Steril 36:333–338, 1981. 52. Karande V, Levrant S, Hoxsey R, et al: Lysis of intrauterine adhesions using gynaecoradiological techniques. Fertil Steril 68:658–662, 1997. 53. Coccia ME, Becattini C, Bracco GL, et al: Pressure lavage under ultrasound guidance: A new approach for outpatient treatment of intrauterine adhesion. Fertil Steril 75:601–606, 2001. 54. Massouras HG: Intrauterine adhesions: A syndrome of the past, with the use of the Massouras duck’s Foot No.2 intrauterine contraceptive device. Am J Obstet Gynecol 116:576–578, 1973. 55. Tsapanos VS, Stathopoulou LP, Papathanassopoulou VS, Tzingounis VA: The role of Seprafilm bioresorbable membrane in the prevention and therapy of endometrial synechiae. J Biomed Matern Res 63:10–14, 2002. 56. Propst AM, Liberman RF, Harlow BL, Ginsburg ES: Complications of hysteroscopic surgery: Predicting patients at risk. Obstet Gynecol 96:517–520, 2000. 57. Vilos GA, D’Souza I, Huband D: Genital tract burns during roller ball endometrial coagulation. J Am Assoc Gynecol Laparosc 4:273–276, 1997. 58. Vilos GA, Brown G, Graham G, et al: Genital tract electrical burns during hysteroscopic endometrial ablation: A report of 13 cases in United States and Canada. J Am Assoc Gynecol Laparosc 7:141–144, 2000. 59. Agostini A, Cravello L, Shojai R, et al: Postoperative infection and surgical hysteroscopy. Fertil Steril 77:766–768, 2002. 60. Siegler AM, Valle RF: Therapeutic hysteroscopic procedures. Fertil Steril 50:685–701, 1988. 61. Lin PC, Bhatnagar KP, Nettleton GS, Nakajima ST: Female genital anomalies affecting reproduction. Fertil Steril 78:899–915, 2002. 62. Crosby WM, Hill EC: Embryology of the müllerian duct system. Obstet Gynecol 20:507–515, 1962. 63. Musset R, Muller P, Netter A, et al: Etat du haut appareil urinaire chez les porteuses de malformations uterines, Etude de 133 observations. Presse Med 75:1227–1232, 1967. 64. Muller PP, Musset R, Netter A, et al: Etat du haut appareil urinaire chez les porteuses de malformations uterines, Etude de 133 observations. Presse Med 75:1331–1336, 1967.
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Chapter 43 Hysteroscopic Management of Intrauterine Adhesions and Uterine Septa 65. Ergun A, Pabuccu R, Atay V, et al: Three sisters with septate uteri: Another reference to bi-directional theory. Hum Reprod 12:140–142, 1997. 66. Elias S, Simpson JL, Carson SA, et al: Genetic studies in complete mullerian fusion. Obstet Gynecol 63:276–281, 1984. 67. Verp MS, Simpson JL, Elias S, et al: Heritable aspects of uterine anomalies. I. Three families aggregates with Müllerian fusion anomalies. Fertil Steril 40:80–86, 1983. 68. Simpson JL: Genes and chromosomes that cause female infertility. Fertil Steril 44:725–739, 1985. 69. Harger JH, Archer DF, Marchese SG, et al: Etiology of recurrent pregnancy loss and outcome of subsequent pregnancies. Obstet Gynecol 62:574–581, 1983. 70. Buttram VC, Gibbons WE: Müllerian anomalies: A proposed classification (an analysis of 144 cases). Fertil Steril 32:140–146, 1979. 71. Hundley AF, Fielding JR, Hoyte L: Double cervix and vagina with septate uterus: An uncommon Müllerian malformation. Obstet Gynecol 98:982–985, 2001. 72. Toaff ME, Lev-Toaff AS, Toaff R: Communicating uteri: Review and classification with introduction of two previously unreported cases. Fertil Steril 41:661–679, 1984. 73. McBean JH, Brumsted JR: Septate uterus with cervical duplication: A rare malformation. Fertil Steril 62:415–417, 1994. 74. Acien P: Incidence of Müllerian defects in fertile and infertile women. Hum Reprod 12:1372–1376, 1997. 75. Simon C, Martinez L, Pardo F, et al: Müllerian defects in women with normal reproductive outcome. Fertil Steril 56:1192–1193, 1991. 76. Cooper JM, Houck RM, Rigberg HS: The incidence of intrauterine abnormalities found at hysteroscopy in patients undergoing elective hysteroscopic sterilization. J Reprod Med 28:659, 1983. 77. Ashton D, Amin HK, Richart RM, Neuwirth RS: The incidence of asymptomatic uterine anomalies in women undergoing transcervical tubal sterilization. Obstet Gynecol 72:28–30, 1988. 78. Heinonen PK, Pystynen PP: Primary infertility and uterine anomalies. Fertil Steril 40:311–316, 1983. 79. Grimbizis GF, Camus M, Tarlatzis BC, et al: Clinical implications of uterine malformations and hysteroscopic treatment results. Hum Reprod 7:161–174, 2001. 80. Stephenson MD: Frequency of factors associated with habitual abortion in 197 couples. Fertil Steril 66:24–29, 1996. 81. Raga F, Bauset C, Remohi J, et al: Reproductive impact of congenital Müllerian anomalies. Hum Reprod 12:2277–2281, 1997. 82. Raga F, Bonilla-Musoles F, Blanes J, Osborne NG: Congenital Müllerian anomalies: Diagnostic accuracy of three-dimensional ultrasound. Fertil Steril 65:523–528, 1996. 83. Ludmir J, Samuels P, Brooks S, Mennuti MT: Pregnancy outcome of patients with uncorrected uterine anomalies managed in a high riskobstetric setting. Obstet Gynecol 75:906–910, 1990. 84. Ben-Rafael Z, Seidman DS, Recabi K, Bider D: Uterine anomalies. A retrospective, matched-control study. J Reprod Med 36:723–727, 1991. 85. Jewelewicz R, Husarni N, Wallach EE: When uterine factors cause infertility. Contemp Obstet Gynecol 16:95, 1980. 86. DeCherney AH, Russell JB, Graebe RA, Polan ML: Resectoscopic management of mullerian fusion defects. Fertil Steril 45:726–728, 1986. 87. Propst AM, Hill JA: Anatomic factors associated with recurrent pregnancy loss. Semin Reprod Med 18:341–350, 2000. 88. Pellerito J, McCarthy S, Doyle M, et al: Diagnosis of uterine anomalies: Relative accuracy of MR imaging, endovaginal sonography, and hysterosalpingography. Radiology 183:795–800, 1992. 89. Dabirashrafi H, Bahadori M, Mohammad K, et al: Septate uterus: New idea on the histologic features of the septum in this abnormal uterus. Am J Obstet Gynecol 172:105–107, 1995. 90. Hickok LR: Hysteroscopic treatment of the uterine septum: A clinician’s experience. Am J Obstet Gynecol 182:1414–1420, 2000. 91. Fedele L, Dorta M, Brioschi D, et al: Pregnancies in septate uteri: Outcome in relation site of uterine implantation as determined by sonography. Am J Radiol 152:781–784, 1989.
92. Fedele L, Bianchi S, Marchini M, et al: Ultrastructural aspects of endometrium in infertile women with septate uterus. Fertil Steril 65:750–752, 1996. 93. Proctor JA, Haney AF: Recurrent first trimester pregnancy loss is associated with uterine septum but not with bicornuate. Fertil Steril 80:1212–1215, 2003. 94. Sheth SS, Sonkawde R: Uterine septum misdiagnosed on hysterosalpingogram. Int J Gynecol Obstet 69:261–263, 2000. 95. Preutthipan S, Linasmita V: A prospective comparative study between hysterosalpingography and hysteroscopy in the detection of intrauterine pathology in patients with infertility. J Obstet Gynaecol Res 29:33–37, 2003. 96. Fayez JA, Mutie G, Schneider PJ: The diagnostic value of hysterosalpingography and hysteroscopy in infertility investigation. Am J Obstet Gynecol 156:558–560, 1987. 97. Soares SR, dos Reis MMBB, Camargos AF: Diagnostic accuracy of sonohysterography, transvaginal sonography, and hysterosalpingography in patients with uterine diseases. Fertil Steril 73:406–411, 2000. 98. Soules MR, Spadoni LR: Oil versus aqueous media for hysterosalpingography: A continuing debate based on many options and few facts. Fertil Steril 38:1–11, 1982. 99. Keltz MD, Olive DL, Kim AH, Arici A: Sonohysterography for screening in recurrent pregnancy loss. Fertil Steril 67:670–674, 1997. 100. Fedele L, Dorta M, Brioschi D, et al: Magnetic resonance imaging of double uteri. Obstet Gynecol 74:844–847, 1989. 101. Carrington BM, Hriacak H, Nuruddin RN, et al: Müllerian duct anomalies: MR imaging and detection. Radiology 176:715–720, 1990. 102. Doyle MB: Magnetic resonance imaging in müllerian fusion defects. J Reprod Med 37:33–38, 1992. 103. Saleem SN: MR imaging diagnosis of uterovaginal anomalies: Current state of the art. Radiographics 23:e13, 2003. 104. Mintz M, Thickman D, Gussman D, Kressel H: MR evaluation of uterine anomalies. Am J Roentgenol 148:287–290, 1987. 105. Pellerito JS, McCarthy SM, Doyle MB, et al: Relative accuracy of MR imaging, endovaginal sonography, and hysterososalpingography. Radiology 183:795–800, 1992. 106. Takagi H, Matsunami K, Noda K, et al: Magnetic resonance imaging in the evaluation of double uterus and associated urinary tract anomalies: A report of five cases. J Obstet Gynaecol 23:525–527, 2003. 107. Brown SE, Coddington CC, Schnorr J, et al: Evaluation of out patient hysteroscopy, saline infusion hysterosonography, and hysterosalpingography in infertile women: A prospective randomized study. Fertil Steril 74:1029–1034, 2000. 108. Jones HW, Jones GES: Double uterus as an etiological factor of repeated abortion, indication and surgical repair. Am J Obstet Gynecol 65:325–331, 1953. 109. Tompkins P: Comments on the bicornuate uterus and twinning. Surg Clin North Am 42:1049–1055, 1962. 110. Ayhan A, Yucel I, Tuncer ZS: Reproductive performance after conventional metroplasty: An evaluation of 102 cases. Fertil Steril 57:1194–1196, 1992. 111. Candiani GB, Fefele L, Parazzini F, Zamberletti D: Reproductive prognosis after abdominal metroplasty in bicornuate or septate: A life table analysis. BJOG 97:613–617, 1990. 112. Israel R, March CM: Hysteroscopic incisions of the septate uterus. Am J Obstet Gynecol 149:66–73, 1984. 113. March CM, Israel R: Hysteroscopic management of recurrent abortion caused by septate uterus. Am J Obstet Gynecol 156:834–842, 1987. 114. Vercellini P, Fedele L, Arcaini L, et al: Value of intrauterine device insertion and estrogen administration after hysteroscopic metroplasty. J Reprod Med 34:447–450, 1989. 115. Fedele L, Arcaini L, Parazzini F, et al: Reproductive prognosis after hysteroscopic metroplasty in 102 women: Life table analysis. Fertil Steril 59:768–772, 1993. 116. Choe JK, Baggish MS: Hysteroscopic treatment of septate uterus with neodymium-YAG laser. Fertil Steril 57:81–84, 1992. 117. Jourdain O, Dabysing F, Harle T, et al: Management of septate uterus by flexible hysteroscopy and Nd:YAG laser. Int J Gynecol Obstet 63:159–162, 1998.
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133. Tannous W, Hamou J, Henry-Suchet J, et al: Uterine rupture during labor following hysteroscopy. Presse Med 25:159–161, 1996. 134. Gabriele A, Zanetta G, Pasta F, Colombo M: Uterine rupture after hysteroscopy metroplasty and labor induction. A case report. J Reprod Med 44:642–644, 1999. 135. Halvorson LM, Aserkoff RD, Oskowitz SP: Spontaneous uterine rupture after hysteroscopic metroplasty with uterine perforation. A case report. J Reprod Med 38:236–238, 1993. 136. Angell NF, Domingo JT, Siddiqi N: Uterine rupture at term after uncomplicated hysteroscopic metroplasty. Obstet Gynecol 100:1098–1099, 2002. 137. Howe RS: Third-trimester uterine rupture following hysteroscopic uterine perforation. Obstet Gynecol 81:827–829, 1993. 138. Creinin M, Chen M: Uterine defects in a twin pregnancy with a history of hysteroscopic fundal perforation. Obstet Gynecol 79:879–880, 1992. 139. Al Sakka M, Dauleh W, AL Hassani S: Case series of uterine rupture and subsequent pregnancy outcome. Int J Fertil Womens Med 44:297–300, 1999. 140. Venturoli S, Colombo FM, Vianello F, et al: A study of hysteroscopic metroplasty in 141 women with a septate uterus. Arch Gynecol Obstet 266:157–159, 2002. 141. Kupesic S: Clinical implications of sonographic detection of uterine anomalies for reproductive outcome. Ultrasound Obstet Gynecol 18:387–400, 2001. 142. Kirk EP, Chuong CJ, Coulam CB, Williams TJ: Pregnancy after metroplasty for uterine anomalies. Fertil Steril 59:1164–1168, 1993. 143. Homer HA, Li TC, Cooke ID: The septate uterus: A review of management and reproductive outcome. Fertil Steril 73:1–14, 2000. 144. Marcus S, Al-Shawaf T, Brinsden P: The obstetric outcome of in vitro fertilization and embryo transfer in women with congenital uterine malformation. Am J Obstet Gynecol 175:85–89, 1996. 145. Guirgis RR, Shrivastav P: Gamete intrafallopian transfer (GIFT) in women with bicornuate uteri. J In Vitro Fertil Embryo Transfer 7:283–284, 1990.
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44
Gynecologic Laparoscopy William W. Hurd, Janice Duke, and Tommaso Falcone
INTRODUCTION During the past 25 years, gynecologic laparoscopy has evolved from a limited surgical procedure used only for diagnoses and tubal ligations to a major surgical tool used to treat a multitude of surgical conditions. In fact, laparoscopy has become one of the most common surgical procedures performed in the United States today. For many gynecologic procedures, such as removal of ectopic pregnancies and the treatment of endometriosis, the cost/benefit ratio is well-established, particularly in terms of expense and safety. For other procedures, including laparascopyassisted hysterectomy and treatment of gynecologic cancers, the relative risks and benefits of the laparoscopic approach are still being determined. This chapter gives an overview of the history and modern use of laparoscopy. Laparoscopic complications and specific laparoscopic techniques are considered in subsequent chapters.
HISTORY The first experimental laparoscopy (ceolioscopy) was performed by Dr. Georg Kelling in Berlin in 1901; Kelling placed a cystoscope into the abdomen of dogs to evaluate the ability of insufflated air to stop gastrointestinal hemorrhage.1 Dr. Hans Christian Jacobaeus of Sweden published the first description of laparothoroscopy in 1910 as a technique to evaluate patients with peritoneal tuberculosis. However, laparoscopy made little headway into clinical practice until after World War I. It took until the 1960s for laparoscopy to be accepted in the United States and Europe as a safe and valuable surgical procedure. For many years, gynecologic laparoscopy was performed almost exclusively for diagnostic purposes and for sterilizations. By the 1970s, the role of laparoscopy had expanded to include lysis of adhesions and treatment of endometriosis.2 The technology and equipment advanced over the next three decades such that laparoscopy is now used for a wide variety of procedures ranging from treatment of ectopic pregnancies and ovarian cysts to hysterectomy, incontinence procedures, and management of gynecologic malignancies.
GENERAL TECHNIQUES FOR LAPAROSCOPY Primary Trocar Placement For many years, the standard techniques used for creating a pneumoperitoneum and placing a laparoscopic port into the abdomen were either a closed technique or an open approach.
In the past decades multiple alternative approaches and locations have been reported. The four most common approaches are: 1. Standard closed technique (Veress needle insufflation followed by primary trocar insertion) 2. Direct trocar insertion (no insufflation prior to trocar insertion) 3. Open laparoscopy 4. Left upper quadrant insertion technique. Both reusable and disposable instruments are commonly used. The ultimate safety of many of the newer techniques and instruments has not yet been determined. Standard Closed Technique: Veress Needle and Primary Trocar Insertion
The standard closed technique was used almost exclusively for decades and continues to be widely used today. Both the Veress needle and primary trocar are blindly placed through a periumbilicar incision into the peritoneal cavity. Using this approach with reusable instruments, the combined risk of injuring retroperitoneal vessels, bladder, or bowel has been found to be less than 1 in 1000 cases.3 This approach has become the gold standard against which all other techniques are judged. For the standard technique, the patient is placed in a horizontal position and the abdominal wall is elevated by manually grasping the skin and subcutaneous tissue. This is done to maximize the distance between the umbilicus and the retroperitoneal vessels. An alternative method used to elevate the abdominal wall is to place penetrating towel clips at the base of the umbilicus. In a woman of ideal weight (body mass index [BMI] <25 kg/m2) or only slightly overweight (BMI 25 to 30 kg/m2), the lower anterior abdominal wall is grasped and elevated, and the Veress needle is inserted toward the hollow of the sacrum at a 45-degree angle (Fig. 44-1).4 In the thinnest patients in this group, the retroperitoneal vessels are much closer to the abdominal wall and the margin for error is reduced, with as little as 4 cm between the skin and these vessels. In the obese patient (BMI >30 kg/m2; weight usually greater than 200 pounds), a more vertical approach, approximately 70 to 80 degrees, is required to enter the peritoneal cavity because of the increased thickness of the abdominal wall. Verification that the Veress needle tip is in the peritoneal cavity is done by a number of methods, including the hanging drop test, injection and aspiration of fluid through the Veress needle, and close observation of intra-abdominal pressure during carbon dioxide insufflation. After a pneumoperitoneum has been created, the Veress needle is removed and the primary port trocar
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Ideal weight
Overweight
Obese
11 cm (median)
4 ± 2 cm
3 ± 2 cm 1 ± 2 cm 13 ± 4 cm 10 ± 2 cm 6 ± 3 cm
A
B
C
Figure 44-1 Changes in the anterior abdominal wall anatomy with weight. Diagram of representative sagittal views derived from magnetic resonance and computed tomographic imaging for patients in three groups. A, Ideal weight (body mass index [BMI]<25 kg/m2) B, Overweight (BMI 25–30 kg/m2). C, Obese (BMI >30 kg/m2). An 11.5-cm Veress needle is superimposed on each view for comparison. (Adapted from Hurd WW, Bude RO, DeLancey JOL, et al: Abdominal wall characterization by magnetic resonance imaging and computed tomography: The effect of obesity on laparoscopic approach. J Reprod Med 36:473–476, 1991.)
(most commonly 5 or 10 mm in diameter) is placed at an angle identical to that used for the Veress needle. Direct Trocar Insertion
Direct trocar insertion is a technique whereby the primary trocar is inserted without the Veress needle being previously inserted and insufflating the abdomen with carbon dioxide.5 The primary trocar is inserted at an angle similar to that described for the closed technique. The peritoneal cavity is then insufflated with carbon dioxide through the umbilical port. This technique decreases the risk of extraperitoneal insufflation by allowing the surgeon to confirm intraperitoneal placement of the primary trocar before insufflation. Although small randomized studies have not demonstrated an increased risk of injuries, some series suggest that this technique might increase the risk of bowel injury.5,6 Further large studies are required. Open Laparoscopy
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Open laparoscopy, first described by Dr. Harrith Hasson in 1971, refers to creating a small incision in the abdomen and placing the port through the incision without using a sharp trocar.7,8 The skin and anterior rectus fascia are incised with a scalpel and the peritoneal cavity is bluntly entered with a Kelly or Crile forceps. A laparoscopic port with a blunt-tipped trocar
is then placed into the peritoneal cavity. For the Hasson technique, fascial sutures are used to help maintain a pneumoperitoneum.7 This method almost completely avoids the risk of retroperitoneal vessel injury and is preferred by many laparoscopists for this reason. Although open laparoscopy does not entirely avoid the risk of bowel injury, many laparoscopists use this approach in an effort to decrease this risk in patients with previous abdominal surgery suspected of having adhesions. Left Upper Quadrant Technique
This approach was developed for use in patients with previous abdominal surgery with suspected or known periumbilical bowel adhesions. It is performed by using a left upper quadrant site to place both the Veress needle and primary laparoscopy port into the abdomen. This point, sometimes referred to as Palmer’s point, is in the midclavicular line beneath the lower rib margin. It is important to know the anatomy of the left upper quadrant before using this technique. The most important organs that are closest to this site are the stomach and left lobe of the liver.9 Although a small series has shown the risk of complications to be small, the relative risk of complications with this technique remains to be demonstrated by a large study.10
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Deep vessels Inferior epigastric
Superficial vessels Superficial epigastric Superficial circumflex iliac
Figure 44-2 Ideal port sites in relation to the deep and superficial vessels of the anterior abdominal wall.
Placement of Secondary Ports Secondary ports are required to perform most gynecologic laparoscopy procedures today. After identifying the inferior epigastric vessels by visualizing them intra-abdominally through the laparoscope, one to three secondary ports are placed, depending on the procedure.11 A midline port may be placed 3 to 4 cm above the pubic symphysis. Lateral ports are placed approximately 8 cm from the midline and above the pubic symphysis to avoid the inferior epigastric vessels (Fig. 44-2).12 This lateral site corresponds to McBurney’s point in the right lower quadrant, and is approximately one-third the distance from the anterior iliac crest to the pubic symphysis (see Fig. 44-2). An additional lateral port for the principal surgeon is required for most operative laparoscopy cases. The site chosen is typically at the level of the umbilicus lateral to the rectus muscle. This site offers the surgeon comfortable use of both hands and allows access to most areas of the pelvic or abdominal cavity. Secondary ports are placed with sharp trocars under direct laparoscopic visualization to avoid injuring intraperitoneal structures. These trocars should be placed directly into the peritoneal cavity without tunneling. After removal, the intraabdominal gas pressure is reduced to observe for signs of hemorrhage indicative of abdominal wall vessel injury. If the port diameter is 10 mm or greater, the fascia and peritoneum should be closed with a full-thickness suture to reduce the risk of subsequent herniation.
Removal of Ports and Port Site Closure At the time of port removal, several measures have been advocated in an effort to minimize patient risk. Secondary ports should be removed under direct visualization to detect any bleeding that might have been masked by the port or the intraabdominal pressure. Certainly, any port with stabilizing threads should be rotated counterclockwise for removal, because forcefully pulling out the sleeve without rotation might actually enlarge the fascial defect. All carbon dioxide used for pneumoperitoneum should be allowed to escape before removal of the umbilical port. Not only
will this minimize subsequent shoulder pain, but it will also avoid pushing bowel into the incision sites as residual gas escapes. Some surgeons recommend elevating and shaking the abdominal wall at the umbilicus to dislodge any bowel or omentum that might have partially lodged in the umbilical site, because there is no way to visualize this area after removal of the laparoscope. It has become clear that large port sites are at a small but undeniable risk for subsequent bowel herniation if not securely closed.13 Furthermore, patients with ascites or in whom intraabdominal fluid has been placed for chemotherapy or adhesion prevention are at risk of postoperative leakage through the port site. For these reasons, it is recommended that all extra-umbilical port sites be surgically closed when a trocar greater than 8 mm in diameter was used for port placement or if repeated removal and replacement of the port has enlarged the fascial defect. Although the risk of herniation at the umbilicus appears to be extremely rare, some surgeons recommend closing the fascia at this site as well. Closure of a midline port incision is relatively straightforward, because the anterior and posterior rectus fascial sheaths fuse in the midline. The fascia can be grasped with a Kocher forceps and closed with interrupted absorbable suture under direct visualization. Closure of lateral ports is more of a challenge because the fascia is clearly divided into sheaths. Closure of only one fascial sheath puts the patient at risk of herniation of bowel between the sheaths, often referred to as a Spigelian hernia (see Chapter 45). For this reason, methods have been designed to simultaneously close both layers. When closing secondary ports, it is imperative to do so under direct laparoscopic visualization to avoid bowel injury. One of several transabdominal suture guides are used to place interrupted absorbable suture through both the anterior and posterior fascial sheaths, usually incorporating the peritoneum as well. However, even this technique does not completely prevent subsequent herniation.14 For this reason, any painful bulge appearing beneath a laparoscopic port site should be evaluated ultrasonographically to detect bowel herniation.
POWER INSTRUMENTS Power instruments are often used during laparoscopy because suture ligation, the most common hemostatic method used during laparotomy, is difficult to perform laparoscopically. Electrocoagulation was perhaps the first power instrument used during laparoscopy.2 This instrument is heated by passing electrical current through the tip of a grasping instrument, which is then used to coagulate tissue. In the past 30 years, other methodologies have been developed, most notably electrosurgery. Unipolar electrosurgery passes current through the patient to cut or coagulate tissue. Bipolar electrosurgery was developed in an effort to minimize the risk of inadvertent injury to adjacent tissue, particularly the bowel. Bipolar electrosurgery offers an increased margin of safety because the electrical current is confined to the tip of the instrument, but the cutting ability is reduced. Lasers offer a precise, rapid, and accurate method of thermally destroying the tissue; however, hemostatic effects are lessened and lasers are costly. The ultrasonic scalpel is an ultrasonically activated instrument that moves longitudinally at a rate of 55,000 vibrations per second
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Techniques for Large Vessel Occlusion Occlusion and division of large vessels, such as ovarian and uterine vessels, is an important part of many advanced gynecologic laparoscopy procedures such as hysterectomy and oophorectomy. Traditional suturing with intracorporeal or extracorporeal knot tying for this purpose is relatively slow and difficult for many laparoscopists. Originally, these large vessels were laparoscopically occluded with pretied suture loops or linear stapling devices. With experience, it has been found that these large vessels can be effectively occluded with power sources, including bipolar electrosurgery and the ultrasonic grasper. When occluding the uterine artery during hysterectomy, most of these techniques are associated with a risk of ureter injury.
surgeon controlling the movement of the laparoscope, each quadrant of the abdomen and then the pelvis should be carefully inspected. The spleen is usually difficult to see except in thin women (Fig. 44-3). Care should be taken to inspect the appendix, omentum, peritoneal surfaces, stomach, surface of the bowel, diaphragms, and liver (Figs. 44-4 and 44-5).15 If any suspicious lesions are observed, fluid should be obtained for cytology (pelvic washings) before prior to biopsying the lesion for frozen section.
Tubal Sterilization Laparoscopy is one of the most commonly used techniques for permanent sterilization in the world (see Chapter 28). Original laparoscopic techniques used electrocautery or electrosurgery to coagulate the midportion of the tubes. Other techniques, including clips and Silastic bands, have gained popularity. The pregnancy rates vary by age of the patient, ranging from 1% to 3% after 10 years.16
LAPAROSCOPIC PROCEDURES Diagnostic Laparoscopy Laparoscopy is an invaluable method for assessment of the pelvis in women with acute or chronic pain and in women suspected of having an ectopic pregnancy, endometriosis, adnexal torsion, or other pelvic pathology. In most cases, the laparoscope is placed through an infra-umbilical port and a probe is placed through a second suprapubic port to manipulate the pelvic organs, if only a diagnostic laparoscopy is performed. However, for operative laparoscopy other than the simplest procedures the suprapubic port is not useful and is quite uncomfortable. If operative laparoscopy is performed, the accessory trocars should be placed in the right and left lower quadrants. For advanced laparoscopy, an accessory trocar at the level of the umbilicus lateral to the rectus abdominis muscle will allow the principal surgeon to operate comfortably and have access to the pelvis. If tubal patency is a concern, a dilute dye can be injected transcervically, a procedure termed chromopertubation. Before initiating any surgery, the peritoneal cavity should be thoroughly inspected using a systematic approach. With the
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Figure 44-3
Anatomy of the left upper abdomen.
Figure 44-4 Subdiaphragmatic adhesions of Fitz-Hugh–Curtis syndrome. These two physicians, Dr. Curtis in 1930 and Dr. Fitz-Hugh in 1934, described the relationship between adhesions and gonococcal infection.
Figure 44-5
Liver hemangioma.
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Chapter 44 Gynecologic Laparoscopy Lysis of Adhesion and Tubal Reconstructive Surgery Adhesions are usually the result of previous pelvic infections secondary to pelvic inflammatory disease or a ruptured appendix, endometriosis, or previous surgery. These adhesions may contribute to infertility or chronic pelvic pain. Lysis of adhesions is performed bluntly or by sharp dissection using scissors or a power source. Extreme caution should be used if adhesions less than 1 cm from the ureter or bowel are lysed using unipolar electrosurgery because of the unpredictable nature of current arcing. The other power techniques, such as the ultrasonic scalpel, may be a better choice for adhesiolysis near bowel for surgeons who do not have experience with unipolar cautery. Tubal reconstructive surgery is still performed even in the era of in vitro fertilization (IVF) and is almost exclusively performed laparoscopically. Fertility-enhancing procedures include adhesiolysis, fimbrioplasty, and terminal neosalpingostomy. Before and during these procedures, chromopertubation is carried out to document proximal tubal patency by injecting dilute indigo carmine dye through the cervix using a cannula. Laparoscopic surgery is performed using the principles of microsurgery to avoid tissue damage, including delicate handling of tissues, and minimal use of electrosurgery for hemostasis. Patients with mild tubal disease and preservation of fimbria have excellent pregnancy rates after laparoscopic surgery. Although these patients remain at risk for subsequent ectopic pregnancy, the risk of multiple gestations associated with IVF is avoided for patients who subsequently achieve a viable intrauterine pregnancy. Unfortunately, adhesions often reform after lysis. Multiple techniques have been used in an effort to decrease reformation (see Chapter 52). Gentle tissue handling and good hemostasis also appear to be important. Barrier methods have been shown in clinical trials to decrease adhesions, but have yet to be proven to improve pain relief or future fertility.
Fulgarization of Endometriosis Laparoscopy is the primary surgical approach used to treat endometriosis. Endometriosis lesions may be resected or ablated, using scissors or any of the power instruments. These treatment approaches have been shown to improve fertility and decrease pelvic pain (see Chapter 49).
Ectopic Pregnancy Treatment Laparoscopy has become the surgical approach of choice for most ectopic pregnancies17 (see Chapter 48). The embryo and gestational sac are removed either through a longitudinal incision (linear salpingostomy) or by removing a part of the tube (salpingectomy). Even a ruptured tubal pregnancy can be treated laparoscopically, as long as the patient is hemodynamically stable.
(see Chapter 50).18 The most important concept in adnexal surgery is to avoid spilling the cyst contents whenever possible.
Myomectomy Many women with a symptomatic fibroid uterus prefer a myomectomy over hysterectomy to preserve fertility or the uterus (see Chapter 46).19 In some cases, myomectomy can be performed laparoscopically. The challenges in the case of intramural myomas are related to hemostasis, effective closure of the resulting myometrial defect, and removal of the specimen from the abdomen. Vasopressin can be injected into the uterus to help maintain hemostasis. The excised fibroid can be removed by morcellation or culpotomy. Power morcellators are available to expedite the process. Barrier techniques may be used to decrease subsequent adhesion formation. Some early case series have reported increased risk of subsequent uterine rupture during pregnancy after laparoscopic myomectomy compared to those performed by laparotomy.20 However, several randomized clinical trials have shown no increased risk in expert hands.21 A totally laparoscopic approach should be attempted only by gynecologists skilled in laparoscopic suturing.
Laparoscopic Uterine Nerve Ablation for Pelvic Pain Many women have severe dysmenorrhea that is unresolved despite medical management, but wish to maintain future childbearing potential. In these patients, two laparoscopic approaches have been attempted with some success. Laparoscopic uterosacral nerve ablation (LUNA) is performed by stretching and dividing each uterosacral ligament using electrosurgery or laser alone or in combination with scissors. Care must be taken to avoid injuring the ureters. This procedure has been shown to have some temporary success, but a recent Cochrane review has questioned the validity of this procedure.22 Laparoscopic presacral neurectomy is a second approach for central pain. This technically challenging procedure is performed by careful retroperitoneal dissection between the common iliac artery on the right and the inferior mesenteric artery where it crosses over both left common iliac artery and vein on the left. The superior hypogastric plexus, which includes the presacral nerves, is dissected from the left common iliac vein and periosteum of sacral promontory and a 2- to 3-cm segment is resected. Surgical risks include vascular complications, and longterm risks, such as constipation, are more common than with LUNA. Although both LUNA and laparoscopic presacral neurectomy appear to give some patients at least temporary relief from central pain, many clinicians believe that there is insufficient evidence to recommend the use of nerve interruption in the management of dysmenorrhea, regardless of cause.22
Hysterectomy Ovarian Cystectomy and Oophorectomy Ovarian pathologic conditions, including cysts, commonly result in a gynecologic complaint such as pain. The underlying pathology ranges from physiologic and self-limiting functional cysts to ovarian torsion and other benign conditions, to ovarian malignancy. Ovarian cysts are usually characterized ultrasonographically and treated when necessary by laparoscopy or laparotomy, depending on the size of the cyst and the level of suspicion for malignancy
Laparoscopic hysterectomy, first described by Dr. Harry Reich in 1992, is commonly performed today.23 The three basic laparoscopic approaches for hysterectomy are laparoscopicassisted vaginal hysterectomy (LAVH), laparoscopic hysterectomy, and laparoscopic supracervical hysterectomy. Although the basic techniques for each of these approaches are fairly standardized, controversy exists over the risks, benefits, and most appropriate indication of each.
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LAVH is the most commonly employed and technically straightforward of the three procedures. Using three to four ports, the peritoneal cavity is surveyed and lysis of adhesions is performed if necessary. Then the infundibulopelvic or utero-ovarian ligaments are occluded and divided, depending on whether the ovaries will be removed. The round ligament is divided, the uterovesicle peritoneum is incised, and the bladder dissected from the anterior uterus. This step results in an increased risk of bladder injury compared to either abdominal or vaginal hysterectomy. At this point, the uterine arteries laparscopically are sometimes occluded and divided, although this is associated with an increased risk of ureter injury compared to either abdominal or vaginal hysterectomy. Finally, the posterior cul-desac is incised. The surgeon proceeds vaginally for the remainder of the case, dissecting the vesicovaginal septum anteriorly to enter the anterior cul-de-sac, ligating the uterine vessels if not previously done, removing the uterus and ovaries if appropriate, and closing the vaginal cuff. Laparoscopic Hysterectomy
Laparoscopic hysterectomy, the common second approach, is performed initially like the LAVH, except that the entire hysterectomy is performed laparoscopically. This approach is often used when there is little or no uterine descent, which makes the vaginal approach unfeasible. After the infundibulopelvic (or utero-ovarian) and round ligament are occluded and divided, the bladder is dissected away from the anterior uterus. The ureters are identified, and the uterine vessels and uterosacral ligaments are occluded and divided. The posterior cul-de-sac is incised, the vagina is circumferentially separated from the cervix, and the specimen is removed vaginally. The cuff is closed laparoscopically or vaginally. Supracervical Hysterectomy
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The supracervical hysterectomy is a third common laparoscopic approach to hysterectomy for benign indications.24 The technique begins in a manner identical to LAVH and laparascopic hysterectomy. However, before dissecting the cervix, the fundus is transected at the uterocervical junction. To minimize residual cyclic vaginal bleeding and decrease the risk of developing cervical dysplasia or cancer, the glandular tissue endocervix is cored out or cauterized. The uterine specimen is removed through a 12-mm abdominal port using a power morcellator. This approach eliminates both the vaginal and abdominal incision, thus decreasing the risk of infection. The risk of ureteral injury is also decreased, because the procedure stops above the level of the internal os. However, a risk of subsequently developing cervical dysplasia or cancer remains due to the presence of the cervical stump. For this reason, routine Pap smears are required, and some patients will require additional surgery related to cervical abnormalities. Furthermore, at least two randomized clinical trials have failed to show superior results in bladder function or sexual function.25,26 These studies did show a higher reoperation rate for bleeding and prolapse. Although small trials have tried to assess the value of laparoscopic hysterectomy, a large multicenter, randomized trial that compared laparoscopic with abdominal hysterectomy and laparoscopic with vaginal hysterectomy has provided insight
into the role of this procedure.27 The study confirmed that the laparoscopic approach offers no advantage over the vaginal approach. It also confirmed that the laparoscopic approach is associated with less postoperative pain, shorter hospital stay, and faster convalescence compared with the abdominal approach. It demonstrated that the laparoscopic approach was associated with a slightly higher risk of urinary tract injury. The shorter length of hospitalization with laparoscopic hysterectomy offset some of the additional costs incurred by longer operating room times and the expense of disposable instruments.28
Oncologic Procedures Laparoscopy originally was used in gynecologic oncology for second-look procedures after surgical and chemical treatment of the malignancy. More recently, laparoscopy has been used for the initial staging of gynecologic cancer, including hysterectomy, peritoneal washes with biopsy, partial omentectomy, and pelvic and periaortic lymphadenectomy. Techniques have also been developed for laparoscopically-assisted radical vaginal hysterectomy. The laparoscopic approach to gynecologic cancer remains controversial. There is some concern that laparoscopy might increase the risk of intraperitoneal spread of ovarian cancer. Until the risk, benefits, and the effect on long-term prognosis have been shown to be equal to laparotomy, the laparoscopic approach will remain under close scrutiny.
Risks of Laparoscopy Laparoscopy appears to decrease the traditional risks of surgery such as infection and generalized bleeding compared to laparotomy. However, laparoscopy is associated with several unique complications. These include venous gas embolism related to carbon dioxide insufflation and trocar injuries to bladder, bowel, and blood vessels. During hysterectomy, laparoscopy also appears to increase the risk of bladder and ureter injury compared to hysterectomies performed via laparotomy or transvaginally.29 The methods for avoiding, diagnosing, and treating laparoscopic complications are presented in Chapter 45.
Proficiency It is apparent that advance laparoscopy requires specific training. The level of proficiency required to successfully complete a procedure will depend on many parameters. Criteria that can be used to determine the level of proficiency include the following: ● ● ● ●
operative time rate of conversion to laparotomy blood loss at surgery intraoperative complications.
It is important that each surgeon understands his or her limits before embarking on a complex laparoscopic procedure.
CONCLUSION The role of laparoscopy in gynecologic surgery continues to expand as experience and more sophisticated techniques and instrumentation allow a greater variety of procedures to be safely performed. Many laparoscopic procedures commonly done today
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Chapter 44 Gynecologic Laparoscopy would have required laparotomy in the recent past. Laparoscopy has become the primary surgical approach for many gynecologic procedures, including tubal ligation, treatment of endometriosis and adhesions, and removal of ectopic pregnancies and adnexal structures. Ongoing studies are needed to determine the ultimate utility of laparoscopy for the performance of more complex procedures, including the treatment of malignancies.
PEARLS ●
●
Laparoscopy is one of the most important surgical tools available to the gynecologist and is the surgical approach of choice for a variety of intra-abdominal problems. Knowledge and judgment are required to understand which conditions should and should not be approached laparoscopically.
●
●
●
●
Careful technique will minimize, but not completely prevent, the risk of laparoscopic complications. It is critical to change the angle of insertion, the site of entry, and at times the entry technique according to the body habitus and previous surgical history. The major advantage of laparoscopy is decreased discomfort and disability for the patient. In many cases, cost is decreased as well. Major disadvantages of laparoscopy include an increased risk of bladder and ureter injury during hysterectomy and the uncertain effect on the prognosis of gynecologic malignancies.
REFERENCES 1. Litynski GS: Laparoscopy—the early attempts: Spotlighting Georg Kelling and Hans Christian Jacobaeus. JSLS 1:83–85, 1997. 2. Semm K: Endocoagulation: A new and completely safe medical current for sterilization. Int J Fertil 22:238–242, 1977. 3. Yuzpe AA: Pneumoperitoneum needle and trocar injuries in laparoscopy. A survey on possible contributing factors and prevention. J Reprod Med 355:485–490, 1990. 4. Hurd WW, Bude RO, DeLancey JOL, et al: Abdominal wall characterization by magnetic resonance imaging and computed tomography: The effect of obesity on laparoscopic approach. J Reprod Med 36:473–476, 1991. 5. Kaali SG, Barad DH: Incidence of bowel injury due to dense adhesions at the sight of direct trocar insertion. J Reprod Med 37:617–618, 1992. 6. Mintz M: Risks and prophylaxis in laparoscopy: A survey of 100,000 cases. J Reprod Med 18:269–272, 1977. 7. Hasson HM: Open laparoscopy: A report of 150 cases. J Reprod Med 12:234–238, 1974. 8. Hurd WW, Ohl DA: Blunt trocar laparoscopy. Fertil Steril 61:1177–1180, 1994. 9. Tulikangas PK, Nicklas A, Falcone T, Price LL: Anatomy of the left upper quadrant for trocar insertion. J Am Assoc Gynecol Laparosc 7:211–214, 2000. 10. Tulikangas PK, Robinson DS, Falcone T: Left upper quadrant cannula insertion. Fertil Steril 79:411–412, 2003. 11. Hurd WW, Amesse LS, Gruber JS, et al: Visualization of the bladder and epigastric vessels prior to trocar placement in diagnostic and operative laparoscopy. Fertil Steril 80:209–212, 2003. 12. Hurd WW, Bude RO, DeLancey JOL, Newman JS: The location of abdominal wall blood vessels in relationship to abdominal landmarks apparent at laparoscopy. Am J Obstet Gynecol 171:642–646, 1994. 13. Montz FJ, Holschneider CH, Munro M: Incisional hernia following laparoscopy: A survey of the American Association of Gynecologic Laparoscopists. J Am Assoc Gynecol Laparosc 1:S23–S24, 1994. 14. Cottam DR, Gorecki PJ, Curvelo M, et al: Preperitoneal herniation into a laparoscopic port site without a fascial defect. Obes Surg 12:121–123, 2002. 15. Tulandi T, Falcone T: Incidental liver abnormalities at laparoscopy for benign gynecologic conditions. J Am Assoc Gynecol Laparosc 5:403–406, 1998.
16. Westhoff C, Davis A: Tubal sterilization: Focus on the U.S. experience. Fertil Steril 73:913–922, 2000. 17. Tulandi T, Saleh A: Surgical management of ectopic pregnancy. Clin Obstet Gynecol 42:31–38, 1999. 18. Mettler L, Semm K, Shive K: Endoscopic management of adnexal masses. JSLS 1:103–112, 1997. 19. Miller CE: Myomectomy. Comparison of open and laparoscopic techniques. Obstet Gynecol Clin North Am 27:407–420, 2000. 20. Hockstein S: Spontaneous uterine rupture in the early third trimester after laparoscopically assisted myomectomy. A case report. J Reprod Med 45:139–141, 2000. 21. Falcone T, Bedaiwy MA: Minimally invasive management of uterine fibroids. Curr Opin Obstet Gynecol 14:401–408, 2002. 22. Proctor ML, Farquhar CM, Sinclair OJ, Johnson NP: Surgical interruption of pelvic nerve pathways for primary and secondary dysmenorrhea. Cochrane Database Syst Rev 2003:CD001895. 23. Reich H: Laparoscopic hysterectomy. Surg Laparosc Endosc 2:85–88, 1992. 24. Johns A: Supracervical versus total hysterectomy. Clin Obstet Gynecol 40:903–913, 1997. 25. Kuppermann M, Summitt R, Varner E, et al: Sexual function after total compared with supracervical hysterectomy: A randomized trial. Obstet Gynecol 105:1309–1318, 2005. 26. Thakar R, Ayers S, Clarkson P, et al: Outcomes after total versus subtotal abdominal hysterectomy. NEJM 347:1318–1325, 2002. 27. Garry R, Fountain J, Mason S, et al: The eVALuate study: Two parallel randomised trials, one comparing laparoscopic with abdominal hysterectomy, the other comparing laparoscopic with vaginal hysterectomy. BMJ 328:129–135, 2004. 28. Falcone T, Paraiso MF, Mascha E: Prospective randomized clinical trial of laparoscopic assisted vaginal hysterectomy versus total abdominal hysterectomy. Am J Obstet Gynecol 180:955–962, 1999. 29. Johnson N, Barlow D, Lethaby A, et al: Methods of hysterectomy: Systematic review and meta-analysis of randomized controlled trials. BMJ 330:1478, 2005.
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Complications of Laparoscopic and Hysteroscopic Surgery Howard T. Sharp, Tommaso Falcone, and William W. Hurd
INTRODUCTION It has been almost a century since Jacobaeus performed laparoscopy by inserting a Nitze cystoscope (consisting of an incandescent platinum wire loop and a system of lenses) into a patient’s abdomen. Since that time, significant advances in technology have enabled gynecologic surgeons to use laparoscopes to perform procedures that in the past were done exclusively using an abdominal and vaginal approach. Unfortunately, many laparoscopic advances were developed by trial and error accompanied by significant morbidity and mortality.1 The application of electrosurgery, automated stapling devices, patient positioning, and trocar use produced unique mechanisms for surgical injury, many of which were not predicted. When can new technologies and procedures be considered safe? How many laparoscopic procedures should be performed before a surgeon is deemed proficient? A recent study of the learning curve associated with laparoscopically assisted vaginal hysterectomies (LAVH) suggests that a gynecologist must perform more than 30 cases before morbidity rates are significantly reduced.1 This chapter discusses the most common risks associated with laparoscopy and hysteroscopy, including nerve injuries, injuries to structures, including blood vessels, bowel, bladder, and ureters, and electrosurgical injuries related to laparoscopy. The goal is to provide anatomic and technical information that will allow gynecologists to better prevent, recognize, and manage complications associated with laparoscopic and hysteroscopic surgery.
LAPAROSCOPY Nerve Injury Mechanisms of Injury
Nerve injuries can occur during laparoscopy by one of three basic mechanisms. The most common mechanism of nerve injury in these patients is related to patient positioning. The dorsal lithotomy position puts many nerves of the lower extremity on stretch or under pressure, resulting in temporary paresthesias on awakening. Unfortunately, prolonged stretch or pressure on nerves during surgery can result in neurologic injury that may take months to resolve or may be permanent. Careful patient positioning, especially during prolonged cases, is important to avoid extreme flexion and abduction, as well as pressure points. The second mechanism of nerve injury during laparoscopy occurs during port placement through the anterior abdominal wall and the subsequent repair of the incisions. These abdominal
wall nerve injuries are uncommon. However, because the nerves involved are not easily identified and their anatomic locations vary greatly, the injuries are difficult to completely prevent. For this reason, diagnosis and treatment become paramount. The final mechanism of injury is direct trauma to pelvic nerves during retroperitoneal dissections, including resection of severe endometriosis and lymphadenectomy for cancer staging. Surgeons performing these procedures need a thorough understanding of the location of the nerves at risk to minimize injury. Categories of Nerve Injuries
Nerve injuries are categorized by neurologists according to the degree of injury, which is ultimately reflected in the patient’s subsequent prognosis for recovery. A nerve contusion, referred to as a neurapraxia, is a functional injury in which structural continuity of the nerve is preserved. Diagnostically, it is characterized by a conduction block on electromyelogram. A mild injury results in immediate conduction block at the site of injury with normal conduction distally. A more severe injury results in focal demyelination without disruption of axons, resulting in slowing of conduction velocity across the lesion. Myelin regeneration results in functional recovery within 6 weeks. The next level of nerve injury is termed axonotmesis and involves separation of axons and myelin sheath of a peripheral nerve with preservation of the nerve’s investing sheaths (i.e., endoneurium, perineurium, and epineurium). This more serious nerve injury results in degeneration of the axon distal to the injury site. Wallerian degeneration occurs, characterized by axonal enlargement and breakdown, as well as schwann cell ingestion of myelin fragments. Spontaneous regeneration of the axon usually results in functional recovery within 6 months to 1 year of injury. The most serious level of nerve injury is complete division of the nerve, referred to as neurotmesis. After disruption of the axons, myelin sheath, and investing sheaths, wallerian degeneration occurs. Without further treatment there is no recovery. With operative repair of the injured nerve, the prognosis is variable and ranges from complete recovery to permanent disability. Fortunately, most neurologic injuries associated with patient positioning during laparoscopic surgery do not result in nerve separation and resolve spontaneously with time.2 Those associated with radical surgical dissection may be more likely to be serious and permanent. Specific Nerve Injuries Femoral Nerve
The femoral nerve is the largest nerve of the lumbosacral plexus and is derived from the posterior divisions of the L2, L3, and L4
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Subcostal nerve Subcostal nerve (T12) Iliohypogastric nerve
Psoas major muscle
Ilio-inguinal nerve Iliohypogastric nerve (L1)
Ilio-inguinal nerve (L1) Lateral cutaneous nerve of thigh
Genitofemoral nerve (L1,L2)
Femoral nerve
Iliacus muscle
Genitofemoral nerve
Lateral cutaneous nerve of thigh (L2, L3)
Obturator nerve
Femoral nerve (L2 to L4)
Oburator nerve (L2 to L4)
Lumbosacral trunks (L4, L5)
Figure 45-1 Schematic representation of nerves that can be injured during laparoscopy. (Reproduced from Drake R, Vogl W, Mitchell AWM: Gray’s Anatomy for Students. Philadelphia, Elsevier, 2005.)
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nerve roots (Fig. 45-1). It pierces the psoas muscle and runs inferolaterally within the muscle to emerge between the iliacus and psoas muscles. It then courses under the inguinal ligament to enter the femoral sheath lateral to the femoral artery. The femoral nerve contains motor and sensory components. The motor component supplies the iliacus, quadriceps femoris, sartorius, and pectineus muscles, which are hip flexors and leg extensors. Its main sensory branches include the intermediate and medial cutaneous nerves of the thigh and the saphenous nerve, which supplies the medial leg. Femoral neuropathy during laparoscopy usually results from excessive hip flexion or abduction or from long operating times.2 Patients undergoing vaginal or laparoscopic surgery should be placed in a lithotomy position such that the thigh is flexed no greater than 90 degrees and abducted no greater than 45 degrees. If positioning is changed intraoperatively, these relationships should be maintained. Symptoms of femoral neuralgia include groin pain and weakness of knee extension and thigh flexion. The knee jerk reflex is usually absent. Diagnostic studies such as electromyography and nerve conduction studies can confirm prolonged latencies in the femoral nerve and denervation of the quadriceps muscles.
Obturator Nerve
The obturator nerve arises from the anterior nerve roots of L2, L3, and L4 (see Fig. 45-1). It descends through the psoas muscle, emerging medially at the pelvic brim, and passes through the obturator foramen into the thigh. Its main function is to allow thigh adduction; it supplies motor function to the gracilis, obturator, adductor longus, brevis, and magnus muscles. The most common cause of obturator neuropathy resulting from gynecologic surgery is direct injury during radical pelvic surgery or lymphadenectomy. The obturator neurovascular bundle is also vulnerable during laparoscopic retropubic dissection, particularly during the paravaginal repair of lateral defects of the anterior vaginal wall. Surgeons who operate in these spaces should be well-versed in the anatomy of the obturator nerve. Obturator neuropathy can also occur as a result of excessive hip flexion.3 The mechanism whereby excessive hip flexion can cause obturator nerve injury is anatomic. As the obturator nerve leaves the obturator foramen, it lies directly against bone and can become acutely angulated and deformed if the hips are excessively flexed, particularly during prolonged surgery. Injury to the obturator nerve usually manifests as weakness in the hip adductors and sensory loss in the upper medial thigh.
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Chapter 45 Complications of Laparoscopic and Hysteroscopic Surgery Nerves of the Anterior Abdominal Wall and Inguinal Region: Ilioinguinal, Iliohypogastric, and Genitofemoral
The ilioinguinal, iliohypogastric, and genitofemoral nerves have an overlapping sensory distribution in terms of their cutaneous manifestations, often making it difficult to distinguish between them. The course of these nerves is quite variable. The iliohypogastric and ilioinguinal nerves originate from the T12 and L1 nerve roots of the lumbosacral plexus (see Fig. 45-1). They cross over the quadratus lumborum muscles and pierce the transversus abdominis muscle in parallel at about the level of the anterior superior iliac spine.4 The genitofemoral nerve originates from the L1 and L2 nerve roots to pass anterior to the psoas muscles (see Fig. 45-1). The iliohypogastric nerve supplies sensation to the suprapubic region, and the ilioinguinal nerve supplies sensation to the inguinal canal. The genitofemoral nerve provides sensory innervation to the labial skin (genital branch) and the superior thigh (femoral branch). The most common injury to these nerves is due to abdominal and pelvic incisions with subsequent suture ligature or fibrotic entrapment. With a Pfannenstiel incision, this injury is most likely to occur when the incision extends beyond the fascial aponeurosis to include the medial edge of the internal oblique muscle.5 During laparoscopic trocar insertion, the risk of injuring these nerves increases as the trocars are placed inferior to the anterior superior iliac spine.4,6 Palpation of the anterior superior iliac spine before trocar placement is useful for gaining lateral bearings. Entrapment of these nerves usually manifests as sharp, burning pain and paresthesia. The putative diagnosis is made when local infiltration with a local anesthetic results in pain relief and paresthesia over the sensory distribution of the nerve. Due to the variability of these nerve pathways, entrapment may occur regardless of the precautions taken. For this reason, prompt recognition and treatment are important to avoid prolonged symptoms. Sciatic Neuropathy
The sciatic nerve, derived from L4 through S3, is the largest peripheral nerve in the body and has tibial and common peroneal divisions. It is located anterior to the piriformis muscle, passing through the greater sciatic foramen to course down the posterior thigh. It supplies motor function to the hamstring muscles, which provide leg flexion and thigh extension. It divides superior to the popliteal fossa. Its tibial branch descends within the posterior leg to supply motor function to the plantar flexors of the foot and intrinsic foot flexors. It supplies sensory innervation to the toes and plantar surface of the foot. The common peroneal nerve continues anteriorly around the fibular head to supply motor function to the dorsiflexor and evertors of the foot. It also provides sensation to the lateral leg and dorsum of the foot. The most common mechanism of injury to the sciatic nerve during gynecologic surgery is prolonged hip flexion resulting in nerve tension and stretching. Tension is increased with hip flexion when the knee joint becomes straightened or externally rotated. The sciatic nerve can stretch approximately 1.5 inches when the hip is flexed and the leg extended. Therefore, it is important to be cautious not to use excessive hip flexion when placing patients in stirrups, particularly the hanging type. When free-hanging stirrups are used for gynecologic cases, this injury has been reported in procedures lasting as short as 35 minutes.7
Patients at greatest risk for sciatic nerve injury are long-legged, obese, or short in stature. In long-legged or obese patients, there is a tendency for the hip to rotate externally; in short patients, there is a tendency to have less knee flexion. Stirrups that support the entire leg are the most appropriate for all but the shortest cases. Symptoms of sciatic nerve injury depend on the level of injury, as the nerve divides into two separate divisions. Injury to the nerve trunk results in weakness in the hamstrings, presenting as impaired knee flexion. In cases of peroneal nerve injury, dorsiflexion weakness, or footdrop, occurs. Treatment for Neuropathies
In the case of an apparent neuropathy, the first step is to obtain consultation from a neurologist or physiatrist to assist in both diagnosis and treatment. Treatment typically consists of supportive care with appropriate functional braces and physical rehabilitation. In patients with pain, oral analgesics, tricyclic antidepressants, and anticonvulsant medications may be helpful. Unfortunately, neuropathic pain is usually refractory to opioids. An effective alternative is tramadol, a synthetic centrally acting analgesic used in doses of 50 to 100 mg every 6 hours. Amitriptyline and desipramine may be useful in doses starting at 25 mg daily, gradually increasing to 150 mg daily in divided doses if needed. Gabapentin, an anticonvulsant drug that causes less somnolence than most tricyclic antidepressants, can be given in a starting dosage of 100 mg three times daily, with a maximum dosage as high as 1200 mg three times daily.
Effect of Carbon Dioxide Insufflation and Venous Gas Embolism Effect of Carbon Dioxide Absorption
Carbon dioxide (CO2) gas is the gas of choice for obtaining a pneumoperitoneum for laparoscopy. CO2 gas is highly soluble in blood and large amounts will dissolve in blood. It is rapidly eliminated from the vascular space. CO2 gas is readily absorbed through the peritoneum. The partial pressure of arterial CO2 (PaCO2) increases during the first 15 to 30 minutes of a laparoscopic procedure with intra-abdominal pressures of less than 15 mm Hg. Typically the anesthesiologist adjusts minute ventilation to compensate for this increase. During laparoscopy in a pregnant patient, this adjustment should take into consideration the lower PaCO2 typically found (compensated respiratory alkalosis) to avoid fetal acidosis. After the initial rise and plateau of end-tidal CO2 (ETCO2), any subsequent rise cannot be attributed solely to the CO2 insufflation. PaO2 usually does not change during laparoscopy unless there is a problem. Capnography (ETCO2) and pulse oximetry are reliable markers of arterial gases in healthy patients. This may not apply to American Society of Anesthesiologists (ASA) class II and III. Increases in ETCO2 are usually due to absorption of CO2 from the peritoneal cavity. However, this may also be due to a variety of clinical circumstances that cause a ventilation/perfusion mismatch (V/Q) that increases the physiologic dead space. A steep Trendelenburg position and increased intra-abdominal pressures can accentuate this mismatch, especially in obese patients. A pneumoperitoneum will decrease pulmonary compliance. Obesity will decrease compliance further8 and increase the airway pressure required to ventilate the patient.
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Section 7 Reproductive Surgery Decreased cardiac output will also increase the V/Q mismatch and lead to increase in ETCO2. Other clinical events that can increase ETCO2 are large amounts of CO2 in the subcutaneous spaces (emphysema), CO2 pneumothorax, and CO2 gas embolism. CO2 pneumothorax is usually the result of CO2 gas leaking into the pleural space through diaphragmatic defects. Subcutaneous emphysema does not cause desaturation or increases in airway pressure. Swelling and crepitus are usually seen on the abdomen, sometimes tracking down into the labia. A massive CO2 embolism may initially cause an increase in ETCO2. However, a drop in ETCO2 is typically seen in a gas embolism following this initial increase. Gas Embolism
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A gas embolism is a potentially dangerous complication of laparoscopy and hysteroscopy. Direct intravascular injection of CO2 gas by the pneumoperitoneum needle or trocar can cause a gas embolism. Gas embolization can also occur whenever a significant tear occurs in a large vein during laparoscopy, because the intra-abdominal pressure is higher than the venous pressure. CO2 gas embolism is occasionally seen during diagnostic hysteroscopy, although the mechanism is unclear. CO2 should not be used during operative hysteroscopy. The physical characteristics of CO2, high solubility and rapid clearance, allow the rapid reversal of clinical symptoms from the embolization. Although there may be an initial increase in ETCO2, a decrease in ETCO2 is the most characteristic manifestation of all gas emboli, including CO2. Venous air embolism has been reported in many gynecologic procedures, such as hysterectomy, cesarean section, hysteroscopy, and uterine curettage, as well as in normal spontaneous vaginal delivery. The entry of room air into a venous channel usually requires some pressure gradient. As the height above the heart increases at the gas entry point (an open vein), there is a decrease in local pressure. This pressure gradient facilitates gas entry. In theory, air can be introduced into a vein at the hysteroscopic surgical site that is above the level of the heart. It is therefore prudent to not place the patient in Trendelenburg position during an operative hysteroscopy. Insufflation of CO2 during a hysteroscopy should not commence without purging the tube of room air. Gas should not be used as the cooling system with a laser used for intrauterine surgery. The basic pathophysiology of a venous gas embolism is V/Q mismatch that results in increase in physiologic dead space and right-to-left shunting. One of the earliest manifestations of a gas embolism is a decrease in ETCO2. This decrease is thought to be the result of a V/Q mismatch with increases in physiologic dead space. A pneumothorax can also cause a decrease in ETCO2. Both gas embolism and pneumothorax will cause hypoxemia. The typical clinical findings of a gas embolism that occurs under anesthesia are abnormal heart murmurs. Typically, it is a systolic murmur and the classic water millwheel murmur only occurs if there is a large amount of air in the right ventricle. Other manifestations include tachycardia, arrhythmias, hypotension, and increases in central venous pressure and pulmonary artery pressure. If the patient is conscious, she may complain of chest pain and breathlessness and may demonstrate altered level of consciousness. Physical examination will show the same classic signs in addition to tachypnea. The anesthesiologist will notice an abrupt fall in ETCO2. The initial blood gases of a gas
embolism are similar to those seen with a venous embolus (a clot) that shows hypoxemia from the V/Q mismatch. A respiratory alkalosis from the tachypnea is also seen if the patient is awake. Treatment consists of the following measures: ● ● ●
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Stop the insufflation. Remove the Veress needle. Place in steep Trendelenburg position or left lateral decubitus position to reduce right ventricular outflow obstruction. Correct hypoxemia with 100% oxygen. Remove air from the right atrium using central venous catheter and cardiac massage. Carefully search for evidence of venous injury, using laparotomy if necessary. If no venous injury is seen, observe the patient overnight.
Successful resuscitations after massive venous CO2 embolization have been reported.9,10
Vascular Injuries during Laparoscopy The utilization of extremely small abdominal incisions is the primary advantage of laparoscopy. These incisions are also the source of the most serious complications associated with laparoscopy. Techniques used to place primary and secondary laparoscopic ports into the peritoneal cavity are often accompanied by a small but unavoidable risk of injury to blood vessels located in the anterior abdominal wall and the major blood vessels located in the retroperitoneal space. Theses small incisions, which minimize postoperative discomfort, also limit and delay access to treat any vascular injuries. In addition, the use of CO2 to distend the peritoneal cavity puts patients at the potentially deadly risk of intravascular insufflation. Because of the serious nature of these injuries, every laparoscopic surgeon should develop a plan to deal with these complications before their occurrence. The following is a discussion of methods to avoid injuries and approaches to recognizing and treating injuries should they occur. Veress Needle Injury
The majority of laparoscopic surgeons continue to use a Veress needle to insufflate the peritoneal cavity with CO2 prior to trocar insertion. Although this technique has been used for more than 3 decades with great success, a rare but potentially fatal risk associated with its use is gas embolization when the Veress needle is inadvertently placed in a major vessel. When the Veress needle is placed into the aorta or any other arterial vessel, gas embolization does not occur because the arterial pressure is always higher than the 16 to 20 mm Hg used for insufflation. In these cases, arterial bleeding becomes the major complication (See the section on Retroperitoneal Vessel Injury in this chapter). In contrast, introduction of CO2 when the Veress needle tip is located in a major vein such as the inferior vena cava can result in a large volume of gas in the central circulation with few early warning signs. In either case, the result can be fatal. Avoidance
To avoid injury, laparoscopic surgeons must make every effort to place the Veress needle in the proper angle and direction (discussed in the section Retroperitoneal Vessel Injury). Once the
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Chapter 45 Complications of Laparoscopic and Hysteroscopic Surgery needle is placed, the surgeon should attempt to demonstrate the intraperitoneal location of the needle tip before insufflation. Several methods have been used to demonstrate the intraperitoneal location of the Veress needle tip. Although never experimentally verified, clinical experience supports the belief that these techniques can sometimes detect improper placement of the Veress needle tip before insufflation. First, the Veress needle should be placed with the valve open, so that entering a high-pressure arterial blood vessel will immediately result in extrusion of blood through the needle. Second, after needle placement, a syringe should be used to aspirate the Veress needle to verify that a low-pressure venous blood vessel has not been entered. This is often followed by the hanging drop test, wherein a drop of saline solution is placed at the open end of the Veress needle hub. When the abdominal wall is elevated, the drop often disappears into the shaft if the tip is located in the relatively low-pressure peritoneal cavity, but will usually not disappear if the tip is preperitoneal or embedded in some other structure. The Waggle test is a final maneuver used by some to verify that the needle has not entered the retroperitoneal space. After the needle is placed in the proper position, the hub is moved from side to side using gentle lateral pressure. Lack of lateral mobility suggests that the tip is anchored in the immovable extraperitoneal space of the anterior abdominal wall, and the needle should be slowly withdrawn until lateral movement is possible. This technique is difficult to interpret in obese patients because the abdominal wall itself can limit lateral movement of the Veress needle, even if it is placed through the base of the umbilicus at the proper angle. Retroperitoneal Vessel Injury
Injury of major abdominal blood vessels is a rare but treatable life-threatening complication of laparoscopy, which occurs in approximately 3 per 10,000 laparoscopies.11 These injuries most commonly occur during insertion of the Veress needle or the primary trocar. Prevention
Injury to aorta and inferior vena cava can almost always be avoided by using the appropriate direction and angle for the insertion of both the Veress needle and primary trocar. It is common sense to direct the Veress needle and primary trocar toward the midline because the major retroperitoneal vessels bifurcate near the level of the umbilicus.12 However, because the exact midline is often difficult to gauge after the patient has been draped, the proper angle of insertion becomes especially important. The best angle of insertion appears to change according to the patient’s body mass index (BMI=kg/m2) (see Chapter 44). In patients who are either in the ideal weight or overweight groups (corresponding BMI = 25 kg/m2 and 25 to 30 kg/m2, respectively), the Veress needle and primary trocar should be inserted through the umbilicus at 45 degrees from horizontal.13 A greater angle of insertion in these patients increases the risk of retroperitoneal vessel injury because the bifurcation is beneath the umbilicus in many cases, and the left common iliac vein is beneath the umbilicus in most patients.12 This is particularly important in the thinnest patients, in whom the distance from the umbilicus to the retroperitoneal vessels may be as little as 2 to 3 cm.13
In obese women whose BMI = 30 kg/m2 (e.g., weight of 200 pounds in a woman who is 67 inches tall), the angle must be increased to as much as 70 to 80 degrees from horizontal to reach the peritoneal cavity, because the thickness of the anterior abdominal wall increases dramatically with weight. Fortunately, the distance between umbilicus and vessels is increased in these patients, and the umbilicus tends to be more caudal in relation to the aortic bifurcation. When estimating the proper angle of insertion for either the Veress needle or primary trocar, it is important to know the position of the patient in relation to the floor, because it is natural for the gynecologist to use the floor as a point of reference for horizontal. When a patient is placed in the Trendelenburg position with the head lower than the feet, the angle of insertion relative to the floor must be decreased accordingly to avoid the retroperitoneal vessels. Therefore the patient should not be placed in Trendelenburg position before placement of the primary trocar. Open laparoscopy is an alternative method for obtaining peritoneal access that decreases the risk of retroperitoneal vessel injury to almost zero. Recognition
Immediate recognition of a major vascular injury is necessary to prevent exsanguination. Prompt action must be taken when blood is noted to flow from the open Veress needle or if the patient’s vital signs suggest hemorrhagic shock shortly after the Veress needle or trocar is inserted. In some cases, the first sign of a problem will be a laparoscopic view completely obscured by bright red blood. In other patients, a major vessel injury will manifest as an enlarging retroperitoneal hematoma, which should be approached in an identical manner as a massive intraperitoneal bleeding. Treatment
Major vessel injuries are a rare but unavoidable laparoscopic complication associated with the closed technique for Veress needle and primary trocar placement. Every laparoscopic surgeon that uses a closed technique should develop a plan of action for major vessel injury. The surgeon should also become familiar with the availability of laparotomy instruments, blood products, vascular clamps, and surgical consultants. This is especially important when these procedures are performed in a freestanding outpatient surgical facility. When a major vascular injury is suspected, the following steps should be taken without delay: ● ●
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Alert nursing personnel to prepare for emergency laparotomy. Simultaneously alert anesthesia personnel, who will generally place additional intravenous lines, and call for blood products and additional assistance. Immediately perform a laparotomy via a midline incision. Control the bleeding using direct pressure over the site of injury. Ideally, a trauma surgeon or vascular surgeon can be called in to clearly identify and repair the injury or injuries. In the absence of a surgeon experienced in vascular surgery, the laparoscopic surgeon must be prepared to open the retroperitoneal area and stop the bleeding. If appropriate personnel and facilities to repair the vascular injury are not available, the patient must be transported to a fully equipped trauma center.
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A
B
Figure 45-2 A, Computed tomography scan of a patient with a palpable mass at the trocar site. The hematoma is localized anterior to the fascia of the rectus and oblique abdominal muscles on the patient's right side. B, Blood is seen in the labia as a result of blood that tracked down from the anterior abdomen.
If either the surgeon or facility are not fully prepared to effectively treat a major vascular injury, thought should be given to using only an open laparoscopic technique or performing laparoscopy with a closed technique elsewhere. Abdominal Wall Vessel Injury
The risk of abdominal wall vessel injury during laparoscopy was extremely uncommon before the widespread use of ports lateral to the midline to perform complex operative procedures. The vessels of the anterior abdominal wall at risk for injury can be divided into two groups: superficial and deep. The superficial vessels consist of the superficial epigastric and circumflex iliac arteries, which are located in the subcutaneous tissue. The deep vessels consist of the inferior epigastric artery and vein, which are located beneath the rectus abdominis muscles immediately above the peritoneum. Damage to the deep vessels usually leads to immediate and rapid blood loss, whereas damage to the superficial vessels most often results in a persistent external trickle after the port is removed. Postoperatively, a superficial vessel injury (Fig. 45-2) typically presents with pain at the trocar site and a palpable mass. Postoperative deep vessel injury presents with increasing pain and decreasing hematocrit without a palpable mass because the vessels are located behind the rectus abdominis muscle or the bleeding occurs into the peritoneal cavity. A computed tomography scan will demonstrate the correct location of the hematoma. Prevention
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The primary method for avoiding injury to any of these vessels is to visualize the vessels before lateral trocar insertion. Two techniques have been used for this purpose: transillumination and direct laparoscopic visualization. Transillumination of the anterior abdominal wall with the laparoscopic light source is an effective way to visualize the superficial vessels in almost 90% of
patients.14 The inferior epigastric vessels cannot be seen by transillumination because they lie beneath the rectus abdominis muscle and fascia. However, the inferior epigastric vessels can be directly visualized laparoscopically immediately beneath the peritoneum in 60% of patients where they lie between the insertion of the round ligament at the inguinal canal and the medial umbilical fold (see Chapter 7). When these vessels cannot be visualized, knowledge about their average location can decrease the risk of injury. Because both the deep and superficial vessels are located an average 5.5 cm from the midline, risk of vessel injury can be minimized by placing secondary trocars 8 cm lateral to the midline and 8 cm above the pubic symphysis. This location approximates McBurney’s point, one-third the distance from the anterior iliac spine to the umbilicus on the right, and the corresponding Hurd’s point on the left. Even when ideal sites are used for port placement, there is still a risk of injuring vessels that cannot be visualized because of anatomic variation. Additional precautions that can be taken to minimize the risk of vessel injury in these patients include use of the smallest trocar possible (5 mm vs. 10 or 12 mm) and the use of conical-tipped rather than pyramidal-tipped trocars for lateral port placement. Treatment
Regardless of the precautions taken, anterior abdominal wall vessel injuries sometimes occur. For this reason, every laparoscopic surgeon should have a plan of action to quickly and effectively treat these injuries. When a superficial vessel is found to be bleeding after the port is removed, the most effective approach is to grasp the vessel with a Crile hemostat forceps, followed by cautery or ligation. In cases where the injured vessel cannot be grasped, a pressure dressing is often sufficient.
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Chapter 45 Complications of Laparoscopic and Hysteroscopic Surgery Injury to an inferior epigatric vessel is almost always accompanied by immediate and brisk bleeding at the port site. Treatment consists of the following steps: ●
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Alert nursing and anesthesiology personnel, who might need to place additional intravenous lines and request blood products if the patient becomes hemodynamically unstable. Precisely position sutures above and below the injury using the same instruments and techniques used to close both layers of the fascia when large lateral trocars have been used (e.g., the Endoclose device). These sutures should be tied deep to the skin above the fascia. If a suture cannot be placed quickly, place a Foley catheter through the port site to temporarily slow the bleeding. The catheter is placed directly through the trocar sleeve. After the bulb is inflated with saline solution, the sleeve is removed and the catheter is retracted to hold the bulb tightly against the peritoneal surface. A Kelly forceps can be used to crossclamp the catheter on the skin side to maintain the traction. This is a temporary measure so that the following steps can be performed. Attempt to occlude the injured vessel with a laparoscopic bipolar electrosurgery instrument above and below the injury. After the Foley catheter is loosened, the injured vessel is grasped using a bipolar instrument placed through a contralateral port. If bipolar electrosurgery is unsuccessful, precisely positioned sutures can be placed above and below the injury using the same instruments and techniques used to close both layers of the fascia when large lateral trocars have been used. These sutures should be tied deep to the skin above the fascia. If hemostasis cannot otherwise be achieved, the incision must be widened and the injured vessels individually ligated. The port site incision should be enlarged transversely to at least 4 to 6 cm, the fascia of the anterior rectus sheath incised, and the lateral edge of the rectus abdominis muscle retracted medially. The bleeding vessels can be grasped with hemostatic forceps and selectively ligated above and below the injury.
Delayed bleeding can occur when the abdominal pressure decreases after removal of the carbon dioxide, especially if the method used to occlude an injured vessel becomes loose as the patient awakes from anesthesia and is moved. Signs of hemodynamic instability in the recovery room necessitate a return to surgery, because uncontrolled bleeding from a lacerated inferior epigastric artery can be life-threatening.
Gastrointestinal Injury Despite the continued development of both laparoscopic instruments and techniques, gastrointestinal injury continues to be a common, yet potentially avoidable, complication of laparoscopy. In the past three decades, the risk of this complication appears to have increased from approximately 3 per 10,000 procedures to as high as 13 per 10,000 procedures.11,15 Most bowel injuries occur during placement of the Veress needle or primary trocar when bowel is adherent to the anterior abdominal wall from previous surgery.16 Other gastrointestinal injuries result from operative procedures, including adhesiolysis, tissue dissection, devascularization injury, and thermal injury.
It is essential to minimize morbidity related to gastrointestinal injuries both by prevention and early recognition. Despite an increasing awareness of these risks, gastrointestinal injuries continue to be one of the most lethal types of injuries associated with laparoscopy, with a mortality rate reported as high as 3.6%.15 Severe morbidity and mortality is seen with delayed diagnosis of an unrecognized bowel injury. Gastrointestinal injury should be suspected in any patient who presents postoperatively with increasing nausea, abdominal pain, distension, or fever. Rebound tenderness with a white blood cell (WBC) count that is elevated or depressed with a left shift and X-ray findings demonstrating an ileus or persistent air under the diaphragm are very suggestive of injury. CO2 gas is rapidly absorbed. Air seen under the diaphragm more than 36 hours after surgery, especially in the context of clinical symptoms, warrants further investigation for a gastrointestinal tract injury. Preventive Measures
No method has yet to be discovered that completely prevents gastrointestinal injuries during laparoscopic port placement.17 However, it is well-established that patients with previous abdominal surgery are at increased risk of gastrointestinal injury during laparoscopy because adhesions to the anterior abdominal wall occur in approximately 25% of these patients. For this reason, certain measures have been used in an effort to decrease the risk of gastrointestinal injuries in these patients. Two commonly used techniques for high-risk patients are open laparoscopy, as first described by Hasson, and a left upper quadrant closed technique utilizing Palmer’s point.17–20 Unfortunately, intestinal injury can occur with these approaches as well.17,21,22 Another alternative approach is the use of an optical-access trocar. These devices are designed to increase safety by visualizing each layer of the abdominal wall during port placement. Unfortunately, these devices too have been associated with gastrointestinal injuries, although the actual incidence associated with their use remains uncertain.23 Veress Needle Injuries
The standard closed technique for laparoscopic port placement begins with the blind insertion of a 14-gauge needle with a spring-loaded tip, commonly referred to as a Veress needle. Although the tip of this instrument might decrease the risk of perforating freely mobile bowel, it does not prevent perforation of adherent bowel or bowel with limited excursion related to physiologic attachments (e.g., transverse colon).24 As a general rule, bowel perforation with the Veress needle does not need to be repaired as long as the puncture is not actively bleeding or leaking bowel contents. Stomach Injuries
Injury to the stomach during laparoscopy is relatively uncommon and was reported to occur in less than 3 in 10,000 cases in the earlier days of laparoscopy.25 Risk factors include a history of upper abdominal surgery and difficult induction of anesthesia, because a gas-distended stomach can be below the level of the umbilicus. Routine decompression of the stomach with a nasogastric or orogastric tube before Veress needle or trocar placement has virtually eliminated this risk, especially when a left upper quadrant approach is used.
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Section 7 Reproductive Surgery Trocar injury to the stomach requires surgical repair. Although this is routinely performed by laparotomy, a laparoscopic approach has been reported.26 The defect should be repaired in layers with a delayed absorbable suture, preferably by a surgeon experienced in gastric surgery. The abdominal cavity should be irrigated, being careful to remove all food particles as well as gastric juices. Nasogastric suction is maintained postoperatively until normal bowel peristalsis resumes. Small Intestine Injuries
Intraoperative injuries to the small intestine often go unrecognized during surgery. Injury should be suspected whenever multiple anterior abdominal wall adhesions are present. When the primary trocar and sleeve penetrate completely through both walls of bowel adherent near the umbilicus, the injury will not be visible. Whenever the routine 360-degree survey of the abdominal cavity reveals bowel adherent near the point of insertion, a 5-mm laparoscope should be placed through a lower quadrant port to view the umbilical port site and search for injury. An injury to nonadherent bowel with the Veress needle or a trocar during initial port placement or during lysis of adhesions may fall out of view into the abdomen. If such an injury is suspected, the bowel should be run with laparoscopic bowel graspers or manually using a laparotomy incision until an injury is satisfactorily excluded. Unrecognized trocar injuries to the small intestine usually present with symptoms of nausea, vomiting, anorexia, abdominal pain, peritoneal signs, and possibly fever culminating on the second to fourth postoperative day. Although the bacterial load of the small intestine is low, the contents are not sterile, and sepsis is a common result of undiagnosed injuries. A full-thickness injury to the small intestine of 5 mm or greater should be repaired in two layers, sewing perpendicular to the long axis of the intestine to avoid stricture formation. This can be accomplished with an initial interrupted layer of 3-0 delayed absorbable suture to approximate the mucosa and muscularis. A serosal layer of 3-0 delayed absorbable suture is commonly placed in an interrupted fashion. This is usually performed by laparotomy or by minilaparotomy at the umbilical site, where the injured bowel loop is pulled through to the skin surface and repaired. Laparoscopic repair has also been reported by surgeons with advanced gastrointestinal surgical skills.27 If the laceration to the small bowel exceeds one-half the diameter of the bowel lumen, segmental resection is recommended. Large Intestine Injuries
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Trocar injuries to the large intestines are reported to occur with a frequency of approximately 1 per 1000 cases.28 Due to the high concentration of coliform bacteria in the large intestine, unrecognized injuries can result in serious intra-abdominal infections that can quickly become life-threatening. Intraoperative detection and appropriate treatment of these injuries can greatly reduce subsequent morbidity. Whenever a large intestine injury is suspected, the area should be carefully inspected using atraumatic bowel graspers. If adhesions or anatomy make laparoscopic inspection difficult, laparotomy should be performed. An occult injury to the rectosigmoid colon may be detected using the “flat tire test,” in which the posterior cul-de-sac is filled with normal saline solution and air is injected into the rectum using a proctosigmoidoscope
or a catheter-tipped bulb syringe.29 Visible bubbles indicate a large intestine injury. The management of large intestine injuries depends on size, site, and time between injury and diagnosis. In general, once the diagnosis of colonic injury is made, broad-spectrum antibiotics should be administered and consultation should be sought with a surgeon experienced with these types of injury. In the case of a small tear with minimal spillage of bowel contents, the defect is closed in two layers with copious irrigation. When a larger injury has occurred or the injury involves the mesentery, a diverting colostomy is sometimes necessary. In the case of delayed (postoperative) diagnosis, tissue inflammation usually makes a diverting colostomy necessary. Thermal Bowel Injuries
In the early days of laparoscopy, thermal bowel injuries were associated with the use of electrosurgical equipment secondary to engineering and technical limitations. Modern advances in the use of these and alternative laparoscopic power sources has decreased but not totally eliminated thermal bowel injuries.30 Thermal bowel injuries are pathologically different from traumatic injuries and therefore must be treated differently.31 Thermal injuries are differentiated histologically from traumatic injuries by the presence of coagulation necrosis and the absence of both capillary proliferation and white cell infiltration. Due to this coagulation necrosis, it may take days for the extent of the injury to become grossly visible. As a result, thermal injuries require wide resection of normal-appearing bowel wall adjacent to the visible injury. Port Site Hernia Midline Ports
For the first two decades of laparoscopy, ports were placed almost exclusively in the midline, where the anterior and posterior rectus fascia fuses. These midline ports usually consisted of a 10-mm port at the umbilicus and a 5-mm suprapubic port. Port site hernias at these locations are rare, and those reported are usually limited to omental herniation through the umbilical site. Several actions have been suggested that might reduce the risk of umbilical site herniation, but none have ever been proven to be effective. These include allowing all the carbon dioxide to escape before removal of the umbilical port, avoiding negative pressure within the port during removal by removing the laparoscope and port together or opening the valve, and preventing reversal of anesthesia (with resultant increases in intraabdominal pressure) at the time of umbilical port removal.32 Lateral Ports
The use of lateral ports for more complex operative laparoscopy has resulted in a dramatic increase in the risk of port site herniation. In one retrospective review, port site hernias occurred in 5 of 3500 (0.17%) procedures, with all hernias occurring where ports with diameters of 10 mm or greater were placed lateral to the midline.33 Bowel herniation can occur between fascial layers in what has been called a Spigelian hernia. To minimize the risk of lateral port site herniation, both the anterior and posterior fascial sheaths should be closed after removal of all ports 10 mm and larger. This closure is usually performed with the aid of one of a number of commercially available devices or needles that incorporate the peritoneum as
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Chapter 45 Complications of Laparoscopic and Hysteroscopic Surgery midline suprapubic site, although the decreased risk of bladder injury may be offset by an increased risk of vessel injury. Operative Injuries
The rate of bladder injury associated with operative laparoscopy has increased dramatically to as high as 1 in 300 cases. The most common cause of bladder injury appears to be sharp electrosurgical dissection near the bladder.36 Most of these injuries occur during LAVH or bladder neck suspensions, with a risk of bladder injury reported as 2.8% and 1.9%, respectively.37–39 Resection of endometriosis that obliterates the anterior cul-de-sac is also a risk factor. Recognition
Urinary Tract Injuries
Laparoscopic bladder injuries are often difficult to recognize intraoperatively. Visible leakage of urine at the time of injury is unlikely in patients with a Foley catheter in place. A common sign of bladder injury is significant bleeding from a suprapubic port site placed in the relatively avascular midline. Frank hematuria suggests a full-thickness injury. An uncommon, but pathognomonic, sign of bladder injury during laparoscopy is insufflation of the Foley catheter bag with carbon dioxide.40 If bladder injury is suspected during laparoscopy, an indigo carmine solution can be instilled retrograde through a urethral catheter to detect small leaks. Cystoscopy, or less commonly intentional cystotomy, may be used to inspect the bladder mucosa in questionable cases or to determine the extent of a known injury and ensure that there is no ureteral involvement. Postoperative recognition of a bladder injury can likewise be difficult. Whenever a patient returns within days of laparoscopy with significant abdominal findings, the possibility of an occult bladder injury should be considered.35 Bladder injury should be included in the differential diagnosis in the presence of painful urination and microscopic hematuria (Table 45-1). Elevation of blood urea nitrogen and serum creatinine level suggests intraabdominal spill of urine with transperitoneal reabsorption. Drainage from a suprapubic incision can be evaluated further by instillation of a dilute indigo carmine solution into the bladder. When a bladder injury is diagnosed in the postoperative period, a retrograde cystogram should be performed to determine the extent of the injury. If surgery is indicated because of peritoneal signs of uncertain etiology, cystoscopy before laparotomy may be helpful in determining surgical approach.
Bladder Injury Trocar Injuries
Treatment
Figure 45-3 Computed tomography scan of patient who presented with acute bowel obstruction. Bowel herniation is seen through the fascia on the right where a trocar had been placed.
well as both fascial layers. Unfortunately, port site herniation is not completely prevented by careful fascial closure.34 Closure of the fascia after removal of 5-mm ports is not usually recommended. Although hernias have been reported at 5-mm port sites, they appear to be extremely rare, and closing the fascia at these sites usually requires enlarging the skin incision. Trocar site hernias usually present as a palpable mass beneath a lateral trocar site skin incision that manifests during a Valsalva maneuver. A persistent mass associated with pain indicates an incarcerated hernia and represents a surgical emergency (Fig. 45-3). Standard treatment includes careful surgical exploration of the site and its contents. Any herniated bowel must be inspected carefully. Although simple repair of the peritoneal and fascial defects is all that is required in most healthy patients, in some cases synthetic mesh may be needed.
Injury to the bladder during laparoscopic port placement is relatively uncommon and is usually related to insertion of the primary trocar in the presence of a distended bladder or insertion of a suprapubic midline trocar in a patient whose bladder dome had extended cephalad secondary to previous surgery.35 Draining the bladder with a catheter before primary trocar placement can decrease the risk of trocar injuries to the bladder. In patients with prior lower abdominal surgery, it seems prudent to place the suprapubic trocar above any previous transverse skin incisions. In all patients, an attempt should be made to visualize the superior bladder margin laparoscopically before suprapubic trocar placement.14 In cases in which the superior margin of the bladder cannot be seen, the bladder can be filled with 300 mL of sterile saline to better define its margin. An alternative approach is to use a lateral port site rather than a
Small, uncomplicated, and isolated injuries of the superior portion of the bladder can be treated with catheter drainage alone.41 A retrograde cystogram should be performed after 10 days of
Table 45-1 Signs of Bladder Injury Presenting in the Postoperative Period Hematuria Oliguria Elevated blood urea nitrogen and creatinine levels Lower abdominal pain/distension Peritonitis/sepsis Fistula
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Section 7 Reproductive Surgery continuous drainage and will document spontaneous healing in 85% of patients with small injuries. Surgical repair may be necessary if the Foley catheter is unable to provide adequate bladder drainage due to blood clots and in cases of persistent extravasation. Primary surgical repair is required for larger injuries and those that involve the dependent portions of the bladder, including the trigone, especially if there is a risk of concomitant injury to the urethra or ureter. Closure should be performed using a watertight, multilayered repair with absorbable suture. Laparoscopic repair may be performed in the case of a small injury with adequate surgical expertise and adequate exposure, as long as the ureters and bladder neck are not compromised. Ureteral Injury
Ureteral injury occurs in approximately 1% of laparoscopies.42 The risk is greatest during LAVH, which has become the most common laparoscopic procedure causing ureteral injury, usually related to electrosurgery.36 Laparoscopic ureteral injuries are usually not diagnosed intraoperatively.43 Diagnosis is most commonly delayed until 2 to 7 days after surgery, but has been reported as late as 33 days after surgery. The most common presenting symptoms and findings are abdominal pain, fever, hematuria, flank pain, peritonitis, and leukocytosis. Management of ureteral injury should be undertaken in collaboration with a urologic surgeon. In the majority of cases, percutaneous or cystoscopic stenting techniques can be successfully used. In severe cases, laparotomy is required for ureteral end-to-end anastomosis or bladder reimplantation. Laparoscopic ureteral repair has been reported.44
Ampere (A) – the rate at which current flows Bipolar system – current that flows from an active electrode, through tissue having a cutting or coagulating effect, and returning through a return electrode within the same instrument directly back to the electrosurgical unit, without the need for a return electrode plate on the patient Capacitive coupling – transference of electrical energy from an insulated active electrode to nearby conductive material Cautery — searing through the application of a heated element Coagulating current (interrupted or damped current) — bursts of rapidly increasing current interrupted at intervals such that peak polarity alternates with zero polarity Current (I) – electron flow measured in coulombs per second or the steady current produced by one volt applied across the resistance of one ohm. Current density — the amount of current flow per cross-sectional area normal to the direction of current flow, described in amps per meters squared Cutting current (continuous or undamped current) — continuous highfrequency, low-voltage flow of current from one peak of polarity to the opposite peak without pausing at the zero polarity Desiccation – coagulation of targeted vessels through the process of dehydration Fulguration – coagulation of surface bleeding through spraying long electrical sparks Hertz (Hz) – a unit of frequency expressed in cycles per second Ohm (⍀) – tissue resistance to current Power (P) – work per unit time Radiofrequency – a term given to the current frequency of electrosurgery because it is found within the AM radiofrequency range (500,000 to 4,00,000 Hz) Unipolar (monopolar) system – current that flows from an active electrode, through tissue having a cutting or coagulating effect, and traveling through the patient, exiting by way of return electrode plate, usually on the patient’s thigh, to the electrosurgical unit Vaporization – exploding cells at their boiling point (100°C) as a result of applied energy
Electrosurgical Injuries
Voltage (V) – electric potential expressed in volts
The use of electrosurgery during laparoscopy has resulted in a unique assortment of complications, many of which are difficult to recognize intraoperatively. Although our understanding of electrophysics as it applies to laparoscopic electrosurgery has improved, complications associated with electrosurgery continue to occur.45 Formal electrosurgical training for laparoscopists is uncommon. Unlike the medical laser setup, few institutions require electrosurgery safety courses or credentialing.46 This section provides a basic review of electrophysics as it relates to safety in gynecologic electrosurgery. Table 45-2 defines some of the most commonly used terms.
Watt (W) – the amount of work produced or work done at a rate of one joule per second
“Electrocautery” versus Electrosurgery
Some gynecologists incorrectly use the term electrocautery to refer to electrosurgery. Electrocautery refers to the use of a heated wire to cauterize tissue and is rarely used in laparoscopy today. Electrosurgery uses alternating current to coagulate, desiccate, or vaporize tissue. This alternating current enters the patient’s body, which is included in one of two types of circuits, depending on whether monopolar or bipolar electrosurgery is used. Energy Frequency
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Table 45-2 Electrosurgical Terms
For electrosurgery, current that alternates at a frequency of 60 Hertz (Hz) is transformed to alternate at more than 200,000 Hz, which is in the radiofrequency range. This is
Formulae Energy = Wattage × Time Watts = Voltage × Current
necessary to minimize nerve and muscle stimulation, which occurs at frequencies below 100,000 Hz. At this high frequency, electrosurgical energy passes through the patient with minimal neuromuscular stimulation and no risk of electrocution. Tissue Effects Waveforms: Cutting versus Coagulation
Multiple factors are involved in the tissue effects of electrosurgery. Electrosurgical generators can produce two distinct waveforms that differ in their rate of heat production. The rate of heat production determines whether tissue will be vaporized or coagulated: high heat causes vaporization, whereas low heat results in coagulation. A continuous waveform, referred to as cutting current, produces heat rapidly and thus vaporizes and cuts tissue (Fig. 45-4). The disadvantage of this type of current is that it does not seal vessels very effectively. Cutting current causes cells to vaporize at their boiling point (100°C) without elevating tissue temperatures to high levels, thus minimizing lateral thermal spread.
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Chapter 45 Complications of Laparoscopic and Hysteroscopic Surgery CUT
Blend
Coagulation
to these two extremes. The eschar that forms on both the tissue and the electrode during coagulation has extremely high resistance and must be removed for effective electrosurgery. Monopolar versus Bipolar Electrosurgery
Figure 45-4
Waveforms used for laparoscopic electrosurgery.
An intermittent waveform, referred to as coagulation current, produces less heat. The on time (duty cycle) is reduced, but the peak voltage is increased. Coagulation current seals vessels by producing a coagulum and is thus used for hemostasis. A blended current is a modification of the duty cycle such that the on time is increased and the off time is decreased compared to coagulation current. The resultant current has both cutting and coagulation characteristics, depending on the percent of on and off time. Power Setting
It is intuitive that the power setting influences the tissue effect. Electrosurgery power settings are usually in the range of 10 to 60 watts. It is important to be aware of the standard effective power setting for the electrosurgical task you are performing with the available equipment. A requirement for a much higher power setting to achieve an acceptable clinical effect can be a warning sign of a technical malfunction. High power settings and malfunctioning equipment can result in patient injury. Electrode Size
A smaller electrode surface results in a higher current concentration. The product of the electrode size and power setting is referred to as current density. Consequently, a smaller electrode can achieve the same tissue effect at a lower power setting. This is also the reason the patient is not burned at the site of a large return electrode pad and why electrode contact with a metal retractor that is in full contact with the patient rarely results in tissue damage. Time
At any given power setting and electrode size, longer current application will produce more heat until the tissue is completely desiccated. More heat and higher temperatures increase the amount of thermal damage to adjacent tissue, referred to as lateral thermal spread. Spark versus Contact
Manipulation of the electrode can determine whether vaporization or coagulation occurs. The spark created by holding the electrode away from the tissue surface results in extremely high current density and heat, and is thus ideal for cutting. Holding the electrode in direct contact with tissue decreases the current density and thus is relatively more hemostatic. Tissue Type
Tissue resistance and density both vary widely. Subcutaneous tissue conducts well and cuts quickly. Fibrous tissue conducts poorly and cuts slowly. Most other tissue types are intermediate
Monopolar electrosurgery is the most commonly used modality due to both its flexibility and effectiveness. During monopolar electrosurgery, the active electrode is used at the surgical site for cutting or coagulation. A return electrode pad is placed on a convenient location elsewhere on the patient’s body. The current completes the circuit by passing through the patient from the active electrode to the return electrode. This type of electrode can be associated with capacitive coupling and return electrode site burns. For bipolar electrosurgery, both the active and return electrodes are part of a single instrument used at the surgical site; thus, no distant return electrode is needed. Only the tissue between the two electrodes is included in the electrical circuit, and no current passes through the patient. This type of electrocautery is believed to be safer because the current flow is limited to the area between the electrodes. Interestingly, when bipolar electrosurgery is used to coagulate a bleeding vessel or pedicle, cutting current (rather than coagulation current) is used to desiccate the vessel while applying pressure with a tissue grasper. This causes fibrous bonding of the dehydrated cells of the endothelium without significant lateral thermal spread. Incidental Causes of Electrical Injury Capacitive Coupling
A capacitor is formed when two conductors are separated by an insulator. Capacitive coupling occurs when electrical energy is transferred from an insulator to a conductor in close proximity. Under these conditions, the conductor can cause unwanted transfer of energy to tissue that it inadvertently contacts. The most likely scenario occurring during laparoscopic surgery known to cause capacitive coupling was with the use of hybridtype trocar systems no longer on the market. A capacitor was created when a unipolar electrode (conductor) with a plastic shield (insulator) was passed through a metal trocar sleeve (conductor) attached to a plastic collar (insulator). In this case, capacitive coupling occurred within the trocar sleeve as energy was unable to be dispersed through the abdominal wall. This problem was prevented by removal of the plastic trocar sleeve collar. “All metal” systems allow current to dissipate through the low current density of the abdominal wall. The use of an “all plastic” system is likewise safe because the active electrode is insulated with plastic and surrounded by a plastic trocar sleeve, thus eliminating the second conductor. Furthermore, the use of cutting current provides additional safety due to lower voltage requirements. Insulation Failure
In addition to capacitive coupling, insulation failure can also be a cause of inadvertent electrical injury despite using appropriate trocar sleeve systems. Damaged instruments have been demonstrated to cause stray current that can cause injuries during laparoscopy. Insulation failure can take place anywhere along the shaft of the unipolar instrument or within the electrosurgical cable where a breech of insulation has occurred. All reusable
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Section 7 Reproductive Surgery electrosurgical instruments should be regularly inspected for deterioration and tested by a qualified biomedical technician.
Other Energy Forms Mechanical energy (harmonic scalpel) and laser (light amplification stimulated emission of radiation) energy are not as commonly used as electrical energy in gynecologic laparoscopic surgery. No energy form has been found to be superior to others. Laser energy use requires knowledge of certain safety features. Various media are used to produce the laser, such as CO2 gas or potassium-titanyl-phosphate (KTP) crystal. CO2 laser energy is in the infrared spectrum and is not visible. It is absorbed by water and has a very limited depth of penetration (0.1 to 0.2 mm). It has limited ability to achieve hemostasis, although increasing the spot size will allow some coagulation. Safety goggles are required, although they do not need to be tinted. Its limited depth of penetration makes it useful for incision of tissues and ablation of superficial lesions. The argon and KTP lasers have shorter wavelengths than CO2 and are preferentially absorbed by hemoglobin. They are delivered through flexible quartz fibers. These lasers have a higher depth of penetration (0.3 to 1 mm) and are very useful for coagulation. The neodymium:yttrium-aluminum-garnet (Nd:Yag) laser has a higher wavelength than the argon or KTP laser and is delivered through a flexible fiber. It has been used for hysteroscopic procedures. The depth of tissue penetration can be as high as 3 to 7 mm (noncontact mode). The air-cooled systems carry a risk for air embolism. They are often used with sapphire tips that allow direct contact with tissue.
HYSTEROSCOPY As with most complications, accurate data on complications of hysteroscopy are not available, and prevalence rates from the literature have a tendency to underestimate the occurrence. Table 45-3 lists the most frequently reported complications. Probably the most frequently seen complication is inability to
Table 45-3 Complications Associated with Hysteroscopy Short-Term Trauma Cervical lacerations False passage Uterine perforation Bleeding Introperative Postoperative Infection Distension media CO2 embolus Fluid overload Hyponatremia Air embolus
Long-Term
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Postoperative hematometra Cancer after endometrial ablation Pregnancy after endometrial ablation Poststerilization tubal syndrome Recurrence of menstrual disorder
complete the procedure because of inexperience or inadequate visibility of the uterine cavity. The most common traumatic injuries seen with operative hysteroscopy are those associated with insertion of the hysteroscope into the uterine cavity. Difficulties in inserting the hysteroscope are associated with cervical lacerations or creation of a false passage. Steps that can be used to diminish this complication include use of laminaria tents, if the patient is not allergic to shellfish, or the use of misoprostol (off-label use). Results of the efficacy of misoprostol on cervical dilatation are mixed. This is often due to the differences in dose, frequency, timing, and route of administration as well as menopausal status. Misoprostol 400 μg taken orally 12 and 24 hours before the procedure is efficacious in both premenopausal and postmenopausal patients. Some patients report lower abdominal cramps and bleeding after the use of this drug. Uterine perforation usually occurs at the time of insertion of the cervical dilators or the operative hysteroscope. Perforation is more common in postmenopausal women, patients with cesarean section scars, and those with adenocarcinoma. The procedures that are most commonly associated with perforation are resection of septa or adhesions and myomectomy. Most uterine perforations are small, fundal, and require no specific treatment. If they occur laterally, laparoscopy is mandatory to assess potential uterine artery laceration. If they occur on the fundus, laparoscopy should be considered. At laparoscopy, a small fundal perforation that is not actively bleeding requires no further treatment other than a discussion with the patient that she has an increased risk of uterine rupture in a subsequent pregnancy. If a perforation occurred with an energy form such as the electrical loop, then laparoscopy or laparotomy to assess potential bowel burn is necessary. Persistent or worsening postoperative pain and nausea or fever are symptoms that suggest a complication such as bowel injury. The signs that uterine perforation has occurred during the operative procedure are the dramatic increase in fluid deficit as the fluid leaks into the peritoneal cavity and difficulties in maintaining proper uterine distension. Uterine rupture in a term pregnancy has been reported after hysteroscopic resction of a uterine septum without perforation.47
Uterine Bleeding Uterine bleeding can occur as a result of resection of any intrauterine lesion. Resection of a septum in the wrong plane can result in bleeding. Resection of submucous myomas can be associated with excessive bleeding. The intrauterine pressure usually tamponades most bleeding vessels. Decreasing the pressure slightly may identify the bleeding vessel so that it can be coagulated. If bleeding continues to the point that visibility is compromised, the procedure should be terminated and measures introduced to tamponade the area. The easiest approach is to introduce an intrauterine balloon such as a pediatric Foley catheter and inflate the balloon with 5 to 10 mL of fluid. The catheter is left in place for 6 to 8 hours. During this time a drop in blood pressure without any blood loss through the catheter suggests a large arterial bleed within the peritoneal cavity and surgery is required.
Distension Media The choice and proper use of the distension media is critical for a safe operative procedure. CO2 is often used for diagnostic
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Chapter 45 Complications of Laparoscopic and Hysteroscopic Surgery hysteroscopies but not for operative procedures. The CO2 is insufflated with a special device that delivers the gas at a maximum flow of 100 mL/minute and a maximum pressure of 100 mm Hg. Embolism of CO2 gas has been reported as a potential complication of the use of this gas. CO2 embolism has been especially described with the use of this gas when performing hysteroscopic surgery with the Nd:Yag laser. Complications related to a fluid distension medium are relatively uncommon but can cause significant morbidity and mortality. These complications occur as a result of absorption of fluid. Excessive absorption of fluid can cause fluid overload and possibly electrolyte disturbances. Absorption of fluid during a hysteroscopic procedure is dependent on several variables: ●
● ● ●
the intrauterine pressure from the infused fluid (should be kept at approximately 70 mm Hg) extent of surgical trauma to the uterus length of the procedure inflow and outflow rates.
One of the earliest distension media used is 32% dextran in 10% dextrose. It is a high-viscosity branched polysaccharide. Although visibility is excellent, the fluid crystallizes easily on instruments. The fluid is usually infused under pressure. Fluid overload can occur with this agent even with volumes of 500 mL due to the hydrophilic nature of this agent. The plasma volume is expanded by 860 mL for every 100 mL absorbed. Although at higher doses pulmonary edema is due to fluid overload, noncardiogenic pulmonary edema has also been reported. Coagulopathy and mild electrolyte disturbances can occur. It is recommended that volumes less than 500 mL be used. Hypersensitivity reactions have been reported with low doses.48 Fluid distension media that are used with monopolar electrical current have no sodium. Fluids with electrolytes will cause dispersal of the monopolar current. Fluids with electrolytes such as normal saline solution can be used with bipolar current. The potential complication of all liquid distension media is fluid overload. Sodium-free distension media may also cause serum electrolyte disturbances. Sodium-free fluids that have been used for operative hysteroscopy include glycine 1.5%, 5% mannitol, and 3% sorbitol. Dextrose 5% is no longer used because of the profound hyponatremia. Glycine is metabolized in the liver to ammonia and can be a problem in patients with liver disease. Visual disturbances such as transient blindness and neurologic manifestations may occur as a result of ammonium toxicity rather than an electrolyte disturbance, especially in patients with a history of liver disease. Fluid osmolality is the result of the dissolved solutes. Tonicity or effective osmoles are solutes that cannot freely cross membranes and therefore can cause fluid shifts. Normal serum osmolality is 280 mOsm/L. Osmolality is finely controlled by arginine vasopressin (AVP) produced by the posterior pituitary gland in response to osmoregulator cells in the hypothalamus. Fluid shifts from the extracellular space to the intracellular space will occur to maintain equal tonicity between these compartments. Cellular swelling and dehydration will occur acutely to maintain tonicity. The organic solutes used for hysteroscopic procedures (mannitol, sorbitol, and glycine) are initially restricted to the extracellular fluid compartment. Glycine and sorbitol solutions are hypo-osmolar (178 mOsm/L). Mannitol 5% has an osmolality
Table 45-4 Symptoms of Hyponatremia Headache Nausea and emesis Lethargy, confusion, change in mental status Seizures
of 275 mOsm/L. A large infusion of these hypotonic fluids will cause hyponatremia. Typically release of AVP is suppressed by the osmoreceptors that sense a decrease in serum osmolality. However, postoperatively AVP may be secreted in response to nausea, pain, or pain medications. If the intravenous fluid used for postoperative fluid management is hypotonic, such as halfnormal saline solution, then free water absorption can occur that will exacerbate the hyponatremia. Ringer’s lactate solution or normal saline solution is recommended for postoperative intravenous fluid use. Medical conditions such as Addison’s disease can exacerbate this condition. The intraoperative signs of hyponatremia are often subtle but include tremulousness, hypothermia, and hypoxemia. Postoperatively the patient can complain of mild symptoms that are similar to those seen in many postoperative patients, such as headache and nausea (Table 45-4). Intracerebral fluid shifts cause cerebral edema, increased intracranial pressure, and possible herniation of the brainstem. The intracerebral water gain will cause a decrease in brain osmolality. The brain will rapidly adapt with loss of sodium, potassium, and chloride and slowly adapt by loss of organic osmolytes that lead to loss of cerebral water. Treatment of acute hyponatremia in a symptomatic patient is a medical emergency. Serum sodium levels of 120 to 128 mmol/L can cause permanent brain damage. Admission and close observation is mandatory. Water restriction should be implemented (800 mL/day) and intravenous normal saline solution should be given and the rate adjusted according to the urine output. Furosemide 20 mg can be given intravenously and will induce a hypotonic fluid loss. Monitor the serum sodium every 2 hours. Treatment with hypertonic saline (3%) solution should be considered in the symptomatic patient that does not respond to conservative management. Slow correction of sodium by 0.5 to 1 mmol/L per hour for 3 hours should be the goal. Serum electrolytes can then be repeated. Usually 3 to 7 mmol/L increase is sufficient. The effect of infusion of 1 liter of any electrolyte solution on serum sodium levels can be calculated with the following formula: infusing Na concentration – serum Na concentration Change in serum Na = total body water (0.5 × body weight in kilograms) + 1 For example, if the serum sodium level is 124 mmol/L and the infusing solution is 0.9% sodium chloride (154 mmol/L) and the total body water is 30 L (0.5 × 58 kg ), then 1 L would increase the serum sodium level by 1 mmol/L. The fluid volume required would be too high. A 3% sodium chloride solution (513 mmol/L) would require far less volume to raise the concentration by 1 mmol/L per hour. Raising the serum sodium level too quickly
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Section 7 Reproductive Surgery can cause an osmotic demyelination syndrome. Demyelination of pontine neurons can lead to quadraplegia and other neurologic disorders. Severe symptoms in patients that received glycine may be due to ammonia toxicity, and this should be treated with hemodialysis.49 Proper intraoperative vigilance is essential to avoid the fluid and electrolyte complications of hysteroscopic surgery. Fluid irrigation systems that rapidly calculate fluid deficits can aid in detecting these disorders. If electrolyte-free solutions are used, serum sodium levels should be ordered with large fluid deficits. Termination of the procedure should be considered with fluid deficits of approximately 1 L. If isotonic fluids such as normal saline solution are used, fluid deficits of up to 1.5 to 2.0 L can be tolerated in healthy women. Fluid overload in these patients present with dyspnea and hypoxemia but with normal serum electrolytes.
Infection Infection is an uncommon complication of hysteroscopic surgery. Prophylactic antibiotics are usually not necessary for most hysteroscopic procedures. Endometritis has been reported after different types of ablation procedures. Some of these infections have been severe enough to lead to surgical interventions such as hysterectomy or adnexal removal.
Table 45-6 Recognizing Complications of Hysteroscopy Be suspicious if the following occur: Decrease in body temperature Decrease in oxygen saturation Decrease in end tidal CO2
Cancer has been reported after endometrial ablation in patients who have received unopposed estrogens after the menopause. Ablation procedures in patients with endometrial hyperplasia with atypia may also progress to frank carcinoma. Pregnancies in patients after endometrial ablation can be associated with significant pregnancy loss or placental complications. Patients should be counseled that endometrial ablation does not remove the requirement for proper contraception. Tables 45-5 and 45-6 list the general principles of prevention and recognition of hysteroscopic complications.
PEARLS: LAPAROSCOPY ●
Other Acute and Chronic Complications There are many case reports of complications with hysteroscopy. These include bowel burns, vaginal burns, major vascular injury, ureteral injuries, and death. A syndrome of cyclic cramping pain after endometrial ablation has been reported in women who have had tubal ligation. It is thought to be the result of persistent endometrial tissue near the cornua. The surrounding adhesions may localize the endometrial shed to this area. Fluid may be seen near the cornua on ultrasound. Hysteroscopy with release of some adhesions around the cornua may help this problem. Loculated islands of functional endometrium can cause hematometra with cyclic or noncyclic pain. Hysteroscopic release can help these cases too.
●
●
●
●
●
Table 45-5 Avoiding Complications of Hysteroscopy Preoperative assessment Saline infusion sonohysterogram before myomectomy Careful attention to fluid balance Monitor fluids closely Assess intrauterine pressures Terminate if fluid balance with sodium-free solution shows more than 1 L difference Measure sodium if fluid balance with sodium-free solution is close to 1 L difference Insert hysteroscope under direct vision Never activate electrode out of operator’s view
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Patients undergoing vaginal or laparoscopic surgery should be placed in a lithotomy position such that the thigh is flexed no greater than 90 degrees and abducted no greater than 45 degrees. Vessel injuries can be minimized but not avoided by using the proper direction and angle of insertion for the Veress needle and primary trocar. Secondary trocars should always be placed with care under direct visualization. Gastrointestinal injury is the most lethal injury associated with laparoscopy, with a mortality rate reported as high as 3.6%. Key to minimizing morbidity is prevention and early recognition. Bladder and ureteral injury are usually not recognized intraoperatively and are most commonly associated with sharp electrosurgical dissection and LAVH, respectively. Using cutting current while grasping bleeding pedicles will result in greater hemostasis and less lateral thermal spread and accomplish this at low voltage. Insulation failure can take place anywhere along the shaft of a unipolar instrument or within the electrosurgical cable where a breech of insulation has occurred. All accessories must be thoroughly inspected for deterioration and tested by a qualified biomedical technician regularly.
PEARLS: HYSTEROSCOPY ●
● ● ●
During hysteroscopy there must be careful attention to fluid balance. Measure serum sodium if fluid balance with sodiumfree solution is close to 1 L difference. Insert the hysteroscope only under direct vision. Never activate the electrode out of the operator’s view. Never ignore a drop in ETCO2.
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Chapter 45 Complications of Laparoscopic and Hysteroscopic Surgery REFERENCES 1. Altgassen C, Michels W, Schneider A: Learning laparoscopic-assisted hysterectomy. Obstet Gynecol 104:308–313, 2004. 2. Irvin W, Andersen W, Taylor P, Rice L: Minimizing the risk of neurologic injury in gynecologic surgery. Obstet Gynecol 103:374–382, 2004. 3. Pellegrino MJ, Johnson EW: Bilateral obturator nerve injuries during urologic surgery. Arch Phys Med Rehabil 69:46–47, 1988. 4. Whiteside JL, Barber MD, Walters MD, Falcone T: Anatomy of ilioinguinal and iliohypogastric nerves in relation to trocar placement and low transverse incisions. Am J Obstet Gynecol 189:1574–1578, 2003. 5. Sippo WC, Burghardt A, Gomez AC: Nerve entrapment after Pfannenstiel incision. Am J Obstet Gynecol 80:420–421, 1992. 6. El-Minawi AM, Howard FM: Iliohypogastric nerve entrapment following gynecologic operative laparoscopy. Obstet Gynecol 91:871, 1998. 7. Batres F, Barclay DL: Sciatic nerve injury during gynecologic procedures using the lithotomy position. Obstet Gynecol 62:92S–94S, 1983. 8. Sprung J, Whalley DG, Falcone T, et al: The impact of morbid obesity, pneumoperitoneum, and posture on respiratory system mechanics and oxygenation during laparoscopy. Anesth Analg 94:1345–1350, 2002. 9. Haroun-Bizri S, ElRassi T: Successful resuscitation after catastrophic carbon dioxide embolism during laparoscopic cholecystectomy. Eur J Anaesthesiol 18:118–121, 2001. 10. Cottin V, Delafosse B, Viale JP: Gas embolism during laparoscopy: A report of seven cases in patients with previous abdominal surgical history. Surg Endosc 10:166–169, 1996. 11. Mintz M: Risks and prophylaxis in laparoscopy: A survey of 100,000 cases. J Reprod Med 18:269–272, 1977. 12. Hurd WW, Bude RO, DeLancey JOL, Pearl ML: The relationship of the umbilicus to the aortic bifurcation: Implications for laparoscopic technique. Obstet Gynecol 80:48–51, 1992. 13. Hurd WW, Bude RO, DeLancey JOL, et al: Abdominal wall characterization by magnetic resonance imaging and computed tomography: The effect of obesity on laparoscopic approach. J Reprod Med 36:473–476, 1991. 14. Hurd WW, Amesse LS, Gruber JS, et al: Visualization of the bladder and epigastric vessels prior to trocar placement in diagnostic and operative laparoscopy. Fertil Steril 80:209–212, 2003. 15. Van Der Voort M, Heijnsdijk EA, Gouma DJ: Bowel injury as a complication of laparoscopy. Br J Surg 91:1253–1258, 2004. 16. Bateman BG, Kolp LA, Hoeger K: Complications of laparoscopy— operative and diagnostic. Fertil Steril 66:30–35, 1996. 17. Jansen FW, Kolkman W, Bakkum EA, et al: Complications of laparoscopy: An inquiry about closed- versus open-entry technique. Am J Obstet Gynecol 190:634–638, 2004. 18. Hasson HM: A modified instrument and method for laparoscopy. Am J Obstet Gynecol 110:886–887, 1971. 19. Tulikangas PK, Nicklas A, Falcone T, Price LL: Anatomy of the left upper quadrant for trocar insertion. J Am Assoc Gynecol Laparosc 7:211–214, 2000. 20. Tulikangas PK, Robinson DS, Falcone T: Left upper quadrant cannula insertion. Fertil Steril 79:411–412, 2003. 21. Vilos GA: Laparoscopic bowel injuries: Forty litigated gynaecological cases in Canada. J Obstet Gynaecol Can 24:224–230, 2002. 22. Chapron C, Cravello L, Chopin N, et al: Complications during set-up procedures for laparoscopy: Open laparoscopy does not reduce the risk of major complications. Acta Obstet Gynecol Scand 82:1125–1129, 2003. 23. Sharp HT, Dodson MK, Watts DA, et al: Complications associated with optical-access laparoscopic trocars. Obstet Gynecol 99:553–555, 2002. 24. Chee SS, Godfrey CD, Hurteau JA, et al: Location of the transverse colon in relationship to the umbilicus: Implications for laparoscopic techniques. J Am Assoc Gynecol Laparosc 5:385–388, 1998.
25. Loffer F, Pent D: Indications, contraindications and complications of laparoscopy. Obstet Gynecol Surv 30:407–427, 1975. 26. Spinelli P, Di Felice G, Pizzetti P, Oriana R: Laparoscopic repair of fullthickness stomach injury. Surg Endosc 5:156–157, 1991. 27. Nezhat C, Nezhat F, Ambrose W, Pennington E: Laparoscopic repair of small bowel and colon. A report of 26 cases. Surg Endosc 7:88–89, 1993. 28. Krebs HB: Intestinal injury in gynecologic surgery: A ten-year experience. Am J Obstet Gynecol 155:509–514, 1986. 29. Nezhat C, Seidman D, Nezhat F, Nezhat C: The role of intraoperative proctosigmoidoscopy in laparoscopic pelvic surgery. J Am Assoc Gynecol Laparosc 11:47–49, 2004. 30. Chapron C, Pierre F, Harchaoui Y, et al: Gastrointestinal injuries during gynaecological laparoscopy. Hum Reprod 14:333–337, 1999. 31. Levy BS, Soderstrom RM, Dail DH: Bowel injuries during laparoscopy. J Reprod Med 30:660–663, 1985. 32. Leung TY, Yuen PM: Small bowel herniation through subumbilical port site following laparoscopic surgery at the time of reversal of anesthesia. Gynecol Obstet Invest 49:209–210, 2000. 33. Kadar N, Reich H, Liu CY, et al: Incisional hernias after major laparoscopic gynecologic procedures. Am J Obstet Gynecol 168:1493–1495, 1993. 34. Montz FJ, Holschneider CH, Munro MG: Incisional hernia following laparoscopy: A survey of the American Association of Gynecologic Laparoscopists. Obstet Gynecol 84:881–884, 1994. 35. Godfrey CD, Schilder JM, Rothenberg JM, et al: Occult injuries to the bladder during laparoscopy: report of two cases. J Laparoendosc Surg 9:341–345, 1999. 36. Ostrzenski A, Radolinski B, Ostrzenska KM: A review of laparoscopic ureteral injury in pelvic surgery. Obstet Gynecol Surv 58:794–799, 2003. 37. Gill IS, Clayman RV, Albala DM, et al: Retroperitoneal and pelvic extraperitoneal laparoscopy: An international perspective. Urology 52:566–571, 1998. 38. Wang PH, Lee WL, Yuan CC, et al: Major complications of operative and diagnostic laparoscopy for gynecologic disease. J Am Assoc Gynecol Laparosc 8:68–73, 2001. 39. Soulie M: Multi-institutional study of complications in 1085 laparoscopic urologic procedures. Urology 58:899–903, 2001. 40. Classi R, Sloan PA: Intraoperative detection of laparoscopic bladder injury. Can J Anaesth 42:415–416, 1995. 41. Gomez RG, Ceballos L, Coburn M, et al: Consensus statement on bladder injuries. BJU Int 94:27–32, 2004. 42. Harkki-Siren P, Sjoberg J, Kurki T: Major complications of laparoscopy: A follow-up Finnish study. Obstet Gynecol 94:94–98, 1999. 43. Oh BR, Kwon DD, Park KS, et al: Late presentation of ureteral injury after laparoscopic surgery. Obstet Gynecol 95:337–339, 2000. 44. Tulikangas PK, Gill IS, Falcone T: Laparoscopic repair of ureteral injuries. J Am Assoc Gynecol Laparosc 8:259–262, 2001. 45. Shen CC, Wu MP, Lu CH, et al: Small intestine injury in laparoscopicassisted vaginal hysterectomy. J Am Assoc Gynecol Laparosc 10:350–355, 2003. 46. Lo KW, Yuen P: Mortality following laparoscopic surgery. Gynecol Obstet Invest 48:203–204, 1999. 47. Kerimis P, Zolti M, Sinwany G, et al: Uterine rupture after hysteroscopic resection of uterine septum. Fertil Steril 77:618–620, 2002. 48. Ahmed N, Falcone T, Tulandi T, Houle G: Anaphylactic reaction because of intrauterine 32% dextran-70 instillation. Fertil Steril 55:1014–1016, 1991. 49. Adrogue HJ, Madias NE: Hyponatremia. NEJM 342:1581–1589, 2000. 50. Drake R, Vogl W, Mitchell AWM: Gray’s Anatomy for Students. Philadelphia, Elsevier, 2005.
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46
Uterine Leiomyomas Shahryar K. Kavoussi, Layne Kumetz, and Gregory M. Christman
INTRODUCTION Leiomyomas are benign monoclonal tumors of smooth muscle cell origin. The vast majority are found within the corpus of the uterus, although they can occur throughout the body in any structure containing smooth muscle. Leiomyomas are uncommonly malignant but are responsible for a large number of surgical interventions, including hysterectomy. Although symptoms usually correlate with size, large tumors can be asymptomatic and small tumors can be symptomatic. This chapter reviews the pathophysiology and management of leiomyomas.
PREVALENCE Uterine leiomyomas (also known as fibroids or myomas) are the most common benign pelvic tumors found in women. As many as 50% of reproductive-age women will have clinically apparent uterine leiomyomas, and 25% of women have symptomatic leiomyomas. On pathologic examination, 77% of hysterectomy specimens contain one or more uterine leiomyomas.1 Although benign, uterine leiomyomas are associated with significant morbidity, including abnormal uterine bleeding, chronic pelvic pain, impaired fertility, and recurrent pregnancy loss. In the United States, leiomyomas are cited as the primary indication for hysterectomy in more than 250,000 cases per year and account for over $5 billion in healthcare costs annually.2
CLASSIFICATION Uterine leiomyomas are typically classified into subgroups by their position relative to the layers of the uterus. Subserosal myomas occur near the serosal surface of the uterus. They may have either a broad or pedunculated base and can extend between the folds of the broad ligament. Intramural myomas originate within the myometrium and may enlarge enough to distort the uterine cavity or the serosal surface. Submucosal myomas develop just below the endometrium and with progression protrude into the uterine cavity. These can also be either pedunculated or broad-based. Cervical myomas, on the other hand, are derived from cells in the cervix as opposed to the corpus of the uterus (Fig. 46-1). Leiomyomas can occur singly but are most often multiple. They can vary greatly in size from microscopic to multinodular tumors that can weigh as much as 50 pounds and give the patient the appearance of a term gravid uterus. On physical examination,
the size of a uterus containing leiomyomas (a fibroid uterus) is frequently described in terms of weeks, comparable to a gravid uterus.
CLINICAL IMPACT Although at least 50% of uterine leiomyomas are asymptomatic, many women have significant symptoms that impact their quality of life and warrant treatment. The major clinical manifestations of uterine leiomyoma can be roughly classified into three categories: increased uterine bleeding, pelvic pressure or pain, and reproductive dysfunction.
Abnormal Uterine Bleeding Abnormal uterine bleeding is the most common symptom reported by women with leiomyomas. The most common types of leiomyomas associated with heavy bleeding are intramural or submucosal myomas. The typical bleeding patterns are menorrhagia and hypermenorrhea. Intermenstrual bleeding can represent an intracavitary myoma or specific endometrial pathology. Therefore, these patients must always undergo a more detailed evaluation of the uterine cavity. Very heavy vaginal bleeding can lead to problems such as iron deficiency anemia, which can be severe enough to require blood transfusions, and the necessity for frequent changes of sanitary protection can cause significant distress in work or social situations.3
Chronic Pelvic Pain Pelvic pain or pressure, the second most common complaint in women with leiomyomas, is frequently described as analogous to the discomfort associated with uterine growth during pregnancy. The pain can occur both during and between bleeding episodes. Posterior leiomyomas may give rise to low back pain, whereas anterior leiomyomas may compress the bladder. Leiomyomas that become large enough to fill the pelvis may potentially interfere with voiding or defecation or may cause dyspareunia. Very large leiomyomas can on occasion outgrow their blood supply, leading to tissue ischemia and necrosis clinically manifested as acute, severe pelvic pain. Pedunculated leiomyomas can suffer torsion, also causing ischemia and acute pain. During pregnancy, leiomyomas have been known to undergo red degeneration, where hemorrhage occurs within the myoma, also leading to acute pain.3
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Section 7 Reproductive Surgery serosal leiomyomas have ART outcomes consistent with patients lacking leiomyomas.4,16,17
EPIDEMIOLOGY OF UTERINE LEIOMYOMAS
Figure 46-1 Hysterectomy specimen, demonstrating the presence of intramural, submucosal, and subserosal leiomyomas.
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Uterine leiomyomas are believed to influence reproduction in several ways; however, their direct effect on fertility is still a subject of much debate. The incidence of infertility and uterine leiomyomas both increase with advancing maternal age, and no specific data exists to ascertain if the proportion of infertile women with leiomyomas is greater than the proportion of fertile women with leiomyomas. Yet the indirect evidence is substantial. In one review, pregnancy rates among women with leiomyomas distorting and not distorting the uterine cavity were 9% and 35%, respectively, as compared to 40% among controls with no leiomyomas.4 Furthermore, the multiple reports of successful pregnancies among infertile women after myomectomy strongly suggest a connection.5–7 Although exact physiologic mechanisms for reproductive dysfunction are unclear, many plausible theories exist. There is a potential for reduced fecundity if a myoma occurs in the cornual region of the uterus, causing mechanical occlusion of a fallopian tube.3 It is possible that large leiomyomas may impair the rhythmic uterine contractions that facilitate sperm motility.8 It has further been documented that endometrial histology varies in relation to the location of the leiomyoma. Atrophy, as well as alterations in the vascular blood flow produced by sumbucosal leiomyomas, may impede implantation of an embryo, prevent delivery of hormones or growth factors involved in implantation, or interfere with the normal immune response to pregnancy.9–11 Submucosal leiomyomas that distort the uterine cavity are associated with first-trimester pregnancy loss, preterm delivery, abnormal presentation in labor, and postpartum hemorrhage.12 In regard to the effectiveness of assisted reproductive technology (ART), leiomyomas are generally thought to reduce the effectiveness of ART procedures. Early evidence demonstrated that both pregnancy and implantation rates were significantly lower in patients with intramural or submucosal leiomyomas.13,14 In one study, the presence of an intramural leiomyoma decreased the chances of an ongoing pregnancy after in vitro fertilization by 50%.15 The latest evidence suggests that patients with sub-
The diagnosis of uterine leiomyomas increases with age throughout the reproductive years, with the highest prevalence occurring in the fifth decade of a woman’s life. The most common types of leiomyomas associated with heavy bleeding are intramural or submucosal myomas; these tend to be diagnosed at an earlier age and to result in more severe disease in African American women. (larger leiomyomas and greater incidence of anemia) as compared to white women.18,19 Nulliparous women have higher rates of leiomyomas than multiparous women, and the risk of developing leiomyomas decreases consistently with each subsequent term birth.20 Early age at menarche is associated with a twofold to threefold increased risk of developing leiomyomas.21 Leiomyomas clearly demonstrate their hormonal responsiveness in the fact that they form after puberty, have the potential to enlarge during pregnancy, and regress after menopause. However, studies of exogenous hormone treatments, including oral contraceptives and hormone replacement therapy, reveal conflicting data; no clear association can be inferred.22 Twin and family studies suggest a familial predisposition to developing leiomyomas, although further research in the genetics of leiomyomas has yet to be done.22 These studies are hampered by the extremely high incidence of leiomyoma formation in the general population. According to some studies, an increase in body mass index (BMI) has been found to increase the risk for uterine leiomyomas by a factor of 2 to 3, and the evidence suggests that adult-onset obesity rather than excessive weight in childhood confers this risk. However, other studies have not observed similar associations with increased BMI.21 The majority of epidemiologic studies find that cigarette smokers are at a 20% to 50% reduced risk for the development of uterine leiomyomas through an unclear mechanism, and that the inverse association was independent of BMI. It is unclear whether this relationship varies as a function of pack-years. No clear relationship has been shown between leiomyomas and specific dietary factors or physical activity.21
PATHOLOGY AND PATHOPHYSIOLOGY Genetics Leiomyomas are defined as monoclonal proliferations of benign smooth muscle.23 Each monoclonal myoma may be associated with various chromosomal translocations, duplications, and deletions.24 Many but not all myomas contain nonrandom cytogenetic abnormalities while the myometrium has a normal karyotype—typically these involve chromosomes 7, 12, and 14. Most of the mutations occur in genes involved in cellular growth or responsible for architectural transcription. Two hereditary disorders have been reported in which uterine leiomyomas are part of a syndrome complex that demonstrates the potential genetic contribution to myoma formation. The first is hereditary leiomyomatosis and renal cell cancer complex. This is an autosomal dominant syndrome with smooth muscle
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Chapter 46 Uterine Leiomyomas tumors of the uterus, skin, and kidney. The second is a syndrome of pulmonary leiomyomatosis and lymphangiomyomatosis (LAM) that is the result of mutations in one of the two genes responsible for tuberous sclerosis, a syndrome that results in multiple hamartomas.
Pathology Grossly, myomas usually appear as discrete, round masses that are lighter in color than the surrounding myometrium, with a glistening, pearly white appearance. Histologic features include smooth muscle fibers that form interlacing bundles, with fibrous tissue in between the bundles. A more detailed description is found in Chapter 8.
Endocrinology The influence of steroidal hormones is central to the theory of clonal expansion of leiomyomas. Myomas are responsive to estrogen and progesterone and are therefore more likely to increase in size and cause associated symptoms in women of reproductive age. Serum concentrations of circulating estrogen or progesterone have not been found to be increased. Tumor initiators and yet-to-be-determined genetic factors are involved in key somatic mutations that facilitate the progression of a normal myocyte into a leiomyocyte responsive to estrogen and progesterone. Estrogen receptors, progesterone receptors, and epidermal growth factor receptors (EGFR) are integral
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in the development of myomas.25 Studies have shown that, in comparison with the normal myometrium, myomas have an increased concentration of estrogen receptors and progesterone receptors.26,27 Aromatase p450 is overexpressed by leiomyomas.28,29 Therefore, in addition to circulating estrogen acting on the ER, the local conversion of circulating androgens to estrogens may be important in potentiating the actions of estrogen in the leiomyocyte (Fig. 46-2).30 Traditionally, estrogen was thought to be the primary hormonal mediator of myoma growth. Although progestins have been applied for the treatment of bleeding from symptomatic myomas, recent studies have shown that progesterone may play a much greater role as a mediator of myoma growth than previously thought.31 The antiprogestin RU486 (mifepristone) has been shown to decrease the size of myomas,32,33 and another study showed that myomas in the secretory phase have increased mitotic counts compared to those in the proliferative phase.34 Growth of neoplastic tumors is the result of accelerated cellular proliferation, which outpaces the inhibitory effect of apoptosis. Apoptosis has been shown to be inhibited in uterine leiomyomas. Progesterone has been shown to increase the antiapoptotic protein, bcl-2.35 Therefore, the stimulation of myoma expansion may be a function of the suppression of apoptosis by progesterone. It has been observed in vitro that the addition of progesterone to cultured leiomyoma cells increased the expression of bcl-2 when compared to controls.35 Normal
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Figure 46-2 Sex steroid hormone action. Estrogen and progesterone exert action through binding of specific receptors, which then bind to DNA at specific response elements. Binding of estrogen and progesterone at a variety of genes has different effects in various cells. Figure provided to the public via the internet by Fisher Scientific, Inc. (www.fishersci.com).
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Section 7 Reproductive Surgery myometrium did not express increased levels of bcl-2 in the presence of progesterone. The complex process of apoptosis involves not only the bcl-2 family, but Fas/FasL and Rb-1.36 Martel and coworkers have described the various apoptotic pathways deficient in leiomyomas and potential corresponding targets for therapy of myomas. The role of apoptosis in the pathogenesis of myomas is a promising area for future research, with a great potential for clinical application. The synergistic interplay between estrogen and progesterone signaling in the pathophysiology of myoma growth has been observed as well. The increase in progesterone receptors as a result of increased estrogen has been well established. An in vitro study showed that progesterone up-regulates the expression of EGF, and estrogen also increases the expression of EGFR.25
Pregnancy and Leiomyomas The influence of the pregnancy-induced endocrine milieu on a leiomyoma is complex. There are many reports of dramatic leiomyoma growth in pregnancy; however, all prospective studies have shown that most leiomyomas demonstrate no change in diameter from the first trimester to delivery. Essentially, it is impossible to predict which myoma will grow. The main potential complications in pregnancy are pain and pregnancy wastage. Pain can be the result of myomatous degeneration. This phenomenon can be the consequence of necrosis from decreased blood supply to a subserosal or pedunculated myoma. Usually there is localized pain and a cystic or heterogeneous pattern on ultrasound. Complications were often due to preterm delivery, severe postpartum hemorrhage, and placenta previa. Lower uterine segment myomas may increase the probability of cesarean section due to obstruction or malpresentation.
DIAGNOSTIC IMAGING AND LEIOMYOMAS Imaging has become an integral aspect of the evaluation of leiomyomas. Myoma size and location can be assessed to varying degrees, depending on the imaging technology applied to the evaluation process. Ultrasonography, hysterosalpingography (HSG), and magnetic resonance imaging (MRI) are currently the modalities most commonly utilized to image myomas.
Additional information regarding intracavitary masses, such as submucous myomas, may be obtained by means of saline infusion sonohysterography. This imaging technique consists of real-time transvaginal ultrasound during which sterile saline solution is injected into the uterine cavity. The saline is injected transcervically via a small-caliber catheter. As the uterine cavity is distended by the saline solution, intracavitary masses may be visualized as echogenic structures against the echolucent background of the distension media.40 Intramural myomas within close proximity of the endometrial cavity may also be assessed by sonohysterography. In addition, entities such as endometrial polyps and uterine anomalies such as adhesions may also be detected. Sonohysterography can be used not only to diagnose submucous myomas, but also to assess the potential access to surgical intervention.41 Three-dimensional ultrasound42 and color Doppler ultrasound43 are increasingly being applied to the evaluation of myomas for imaging. Color Doppler ultrasound highlights vascular flow, which is usually increased at the periphery of myomas and decreased centrally.42,43
Hysterosalpingography HSG is a screening test for intracavitary anatomic defects and entails injection of iodine contrast dye transcervically, via a catheter, into the uterine cavity with radiologic assessment under fluoroscopy (see Chapter 29). HSG is performed in the follicular phase of the menstrual cycle to avoid interfering with ovulation or a potential pregnancy. Because the HSG instillation medium contains iodine, an iodine-allergic patient requires premedication with glucocorticoids and antihistamines before the procedure.44 Hysterosalpingography allows visualization of submucous myomas as the uterine cavity is distended by the contrast medium. The size and contour of the uterus may be altered by submucous myomas. Intramural myomas may enlarge the uterine cavity in a globular manner, and fundal myomas may enlarge the space between the cornuae. Subserosal myomas are not typically noted on HSG; however, if large enough, they may be detected as a mass effect on the uterine cavity.23 In cases where a submucous myoma must be differentiated from an endometrial polyp on HSG, hysteroscopy or sonohysterography play roles as complementary, potentially confirmatory adjuncts.
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Traditional ultrasound is a cost-effective technology for assessing uterine leiomyomas (see Chapter 30 for details). The transvaginal approach is more accurate than abdominal ultrasound. However, abdominal ultrasound may be a useful adjunct to transvaginal ultrasound, if a large uterine size warrants such an approach.22 The presence of myomas may be detected by ultrasound, as uterine enlargement or a nodular contour of the uterus. They may also appear as discrete, focal masses within the myometrium.37,38 Myomas can appear hypoechoic or heterogeneous when compared with the appearance of the myometrium on ultrasound, and they may be characterized by calcification and posterior shadowing.37,39 Sagittal and axial views aid in providing information on the location and size of myomas.
MRI is increasingly being utilized for imaging leiomyomas. The location of myomas can be more accurately documented with MRI than with ultrasound. It is often used to evaluate the precise location for surgical planning or before uterine artery embolization mapping. Disadvantages of MRI include cost, limited availability, and an inability to perform the procedure in patients with morbid obesity or claustrophobia. Traditionally, cost had been more of a disadvantage in the past; however, as the expense of MRI decreases, it is more commonly employed in clinical and presurgical evaluation. MRI is contraindicated in patients with pacemakers, defibrillators, metallic foreign bodies, and in rare cases of allergy to gadolinium.45 In T2-weighted images, the endometrial stripe is visualized as a central, high signal; the junctional zone is a low signal; and the
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Chapter 46 Uterine Leiomyomas myometrial areas are an intermediate signal.40 Leiomyomas are represented by variable signal density. Most of the time, they appear as hypodense, well-demarcated masses; however, increased cellularity47 and degeneration may be seen as high signal intensity.46 There is less distinction of the endometrial lining, junctional zone, and myometrium in T1-weighted images. These components are usually homogeneous and, consequently, obscured in appearance. Fatty or hemorrhagic degeneration may be represented by a high signal intensity.46 A detailed description can be found in Chapter 31.
TREATMENT OF LEIOMYOMAS Treatment of leiomyomas has traditionally been interventional. In patients with a menstrual abnormality oral contraceptives have been used successfully, and the presence of a leiomyoma is not considered a contraindication. If the oral contraceptive fails, typically surgery is offered. However, new medical therapy may potentially change this approach. The important concept in the management of leiomyomas is that intervention is not required in asymptomatic women. In the past, it was suggested that intervention was indicated if adenexae could not be palpated; it was also felt that intervention was needed to prevent the onset of symptoms and avoid more difficult surgery in the future. These are no longer considered acceptable reasons for intervention. Rapid growth of leiomyoma was considered a potential sign of malignancy. However, this sign in isolation from other manifestations is not considered prognostic of a sarcoma. Surgery is indicated in women with a history of pregnancy complications. Surgical treatment specifically for infertility is indicated if there is distortion of the uterine cavity. Surgery is sometimes considered in patients with longstanding infertility when no other identifiable cause is found. The latter indication is strongly debated.
MEDICAL TREATMENT OF LEIOMYOMAS Medical treatment of leiomyomas is indicated for the treatment of pain or menstrual dysfunction. Medical therapy has not been investigated for the management of infertility or pregnancyrelated complications.
Gonadotropin-Releasing Hormone Agonists Gonadotropin-releasing hormone (GnRH) agonists are an effective means of medically treating patients with symptomatic leiomyomas. After producing an initial flare of luteinizing hormone (LH) and follicle-stimulating hormone (FSH), GnRH agonists down-regulate the hypothalamic-pituitary-ovarian axis via action on pituitary receptors. The flare effect is due to an initial stimulation of FSH and LH due to the binding of pituitary receptors, after which these receptors are desensitized, with a subsequent decrease in FSH and LH secretion.49 This results in decreased estrogen production. Gonadotropin-releasing hormone agonists have been shown to directly inhibit local aromatase p450 expression in leiomyoma cells,50 thereby presumably resulting in decreased local conversion of circulating androgens to estrogens within the leiomyocyte.
Several studies have concluded that GnRH agonists can directly induce apoptosis and also suppress the cellular proliferation of myomas, presumably via action on peripheral GnRH receptors. Maximum reduction of the mean uterine volume occurs within 3 months of GnRH agonist administration. The decrease in volume is usually in the range of 40% to 80%. However, after the discontinuation of GnRH agonists, myomas will rapidly grow back to their pretreatment size, usually in the span of several months.51 Advantages of GnRH agonists include their use in the perimenopausal transition with add-back therapy for the goal of avoiding hysterectomy. Additionally, laparoscopic myomectomy may be made more feasible with GnRH agonist pretreatment, and GnRH agonists can also be beneficial in a patient who is to undergo hysterectomy to facilitate a vaginal approach rather than an abdominal incision. In a randomized clinical trial comparing the study group (patients receiving GnRH agonist and iron) to a control group (iron alone), preoperative hematologic parameters were improved.52 Although decreased tumor bulk and a decrease in associated symptoms are attained, the potential for unwanted long-term side effects exists; therefore, treatment with GnRH agonist is recommended for no more than 6 months. Common side effects include hot flashes, vaginal dryness, headache, and mood swings. Most importantly, in terms of bone health status, there is a recognized decrease in bone mineral density during therapy.53 Although add-back doses of steroidal hormones can be used with the aim of decreasing this bone loss, the long-term use of GnRH agonists with add-back is impractical and not recommended, especially in younger patients. Add-back therapy with progestins alone will impede the effectiveness of the GnRH agonist in reducing uterine size. In a randomized crossover study, patients were assigned to GnRH agonist alone versus GnRH agonist and a progestin. Uterine volume decreased to 73% of baseline if the agonist was used alone. When the progestin was added the uterine volume increased toward baseline. If the progestin was introduced when the GnRH agonist was started, the uterine volume did not decrease. This effect is attributed to the direct effect of progestins on the leiomyoma.54
Selective Estrogen Receptor Modulators Selective estrogen receptor modulators (SERMs), such as tamoxifen and raloxifene, are compounds that bind to the estrogen receptor and confer an agonist or antagonist effect, depending on tissue specificity. They have been applied to the treatment and prevention of estrogen-responsive breast cancer. Tamoxifen, a triphenylethylene, has antagonist activity in the breast and displays desirable agonist activity in bone and the cardiovascular system as well as mild agonist activity in endometrial tissue.55 Raloxifene, a benzothiophene, has a similar profile and the added benefit of not acting as an agonist in the endometrium.56 In animal models, SERMs have been shown to be effective in decreasing the growth of myomas. Eker rats are a rat strain with a tuberous sclerosis gene defect that can spontaneously develop leiomyomas. In studies, the administration of SERMs was associated with the inhibition of leiomyoma formation in Eker rats.57,58 Guinea pigs require long-term exposure to estrogen for leiomyoma formation to occur. Two groups of oophorectomized
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HO N OCH3
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Chemical structure of asoprisnil.
guinea pigs, an estrogen-only group and an estrogen plus raloxifene group, were compared for myoma formation. A decrease in the size of the induced myomas was observed in the estrogen plus raloxifene group.59 In humans, raloxifene appears effective in decreasing the size of myomas in postmenopausal women,60 but beneficial effects were not significant in premenopausal women.61 A recent study has demonstrated that a combination of raloxifene and GnRH agonist is more effective in reducing leiomyoma volume62 and preventing a decrease in bone mineral density63 than the use of GnRH agonists alone.
Selective Progesterone Receptor Modulators This class of compounds has either agonist or antagonist effects on the progesterone receptor, based on tissue specificity.64 Asoprisnil is a recently developed selective progesterone receptor modulator that, along with its major metabolite, J912, has high affinity for the progesterone receptor, moderately binds the growth hormone receptor, and has a very low binding potential for androgen receptors (Fig. 46-3). Asoprisnil has virtually no affinity for estrogen recptors or mineralocorticoid receptors.65 It differs from the long-term effect of progesterone on the endometrium in that amenorrhea is rapidly established without breakthrough bleeding.66 As it is studied and tested further in clinical trials, there may be a practical use for asoprisnil and other newly developed compounds in this class in the treatment of leiomyomas, especially in women with menorrhagia who are interested in avoiding surgery or maintaining future fertility.
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Surgical treatment is the mainstream therapy for leiomyomas. Hysterectomy represents the only definitive curative therapy; however, myomectomy, endometrial ablation, and myolysis are being used with increasing frequency as alternative therapeutic procedures. Indications for surgical intervention include failure to respond to medical treatment, worsening vaginal bleeding, suspicion of malignancy, or treatment of recurrent pregnancy loss. In postmenopausal women with an enlarging pelvic mass and abnormal bleeding, surgery should be strongly considered. In this population, the incidence of a sarcoma is still uncommon but is higher than the incidence found in the premenopausal population, about 1% to 2%.67
Hysterectomy has been described as the definitive management for symptomatic leiomyomata. When employed, it is highly effective for the carefully selected patient, with symptomatic leiomyomata, who does not desire future fertility. Among hysterectomies performed abdominally versus vaginally for uterine leiomyomata, the abdominal route has been chosen approximately 75% of the time based on data from the late 1980s and early 1990s.68 Vaginal hysterectomy is associated with a lower complication rate and decreased need for blood transfusion. Another advantage of vaginal hysterectomy is the association with shorter operating times.69 Myoma size and location, total uterine size, and the surgeon’s skill are factors that may determine the feasibility of vaginal hysterectomy. Laparoscopy-assisted vaginal hysterectomy, total laparoscopic hysterectomy, and laparoscopic supracervical hysterectomy are minimally invasive surgical methods that are associated with decreased postoperative pain and recovery time in comparison to vaginal and abdominal hysterectomy.70 These surgical modalities may incur increased hospital costs in terms of equipment and operating room time, but they have the recognized advantages listed above. In addition, these options provide the ability to assess the pelvis if the patient also complains of pelvic pain.
Myomectomy Hysterectomy has long been considered the definitive treatment for symptomatic uterine leiomyomas. Yet as more and more women delay childbearing, the incidence of uterine leiomyomas among patients suffering with infertility increases and hysterectomy becomes an unacceptable management option. Therefore, abdominal, laparoscopic, and hysteroscopic myomectomies have become increasingly common treatment modalities for women with leiomyomas and infertility. Hysteroscopic myomectomy is covered in detail in Chapter 42. Myomectomy is the surgery of choice for treating women with symptomatic myomas in those who desire to preserve fertility or to otherwise keep their uteri. It is most useful for subserosal, especially pedunculated subserosal, myomas as well as intramural leiomyomas. Myomectomy entails the surgical removal of myomas by enucleation. It is preferable to use as few incisions as possible to remove myomas from the uterus to minimize adhesion formation as well as to minimize any compromise of the myometrial integrity. The surgeon must be diligent regarding the orientation of the uterus, especially during the repair, to preserve the integrity of the endometrial cavity. A myomectomy can be performed through several types of abdominal incisions, depending on the size of the uterus. Several techniques have been described to decrease blood loss with an abdominal myomectomy, including the use of tourniquets around the lower segment of the uterus to occlude the uterine arteries and the use of dilute vasopressin (Fig. 46-4). Methods employed to minimize postoperative adhesion formation include the use of permanent or absorbable barriers and good surgical technique, minimizing trauma to the tissues, use of nonreactive suture material, and the avoidance of tissue desiccation or aggressive cautery. Incisions placed on the anterior aspect of the uterus seem to be associated with fewer adhesions
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Chapter 46 Uterine Leiomyomas Dilute vasopressin
Ovarian vessels
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Figure 46-5 Dissection of the myoma bed is usually accomplished bluntly, as in open cases. (Courtesy of Dr. T. Falcone.)
Figure 46-4 The peritoneal space has been opened and a tourniquet (e.g., a red rubber catheterization catheter) has been placed around the lower segment of the uterus and tied. Vascular clamps can be placed on the ovarian vessels. Dilute vasopressin is injected into the myoma bed.
than incisions placed in the posterior part of the uterus. Due to the potential risk of uterine rupture, a trial of labor after myomectomy is not recommended by the American College of Obstetricians and Gynecologists.71
Laparoscopic Myomectomy Laparoscopic myomectomy offers many advantages as a minimally invasive technique. This procedure, however, requires appropriate training and advanced endoscopic skills from the surgeon. It is most useful in cases in which myomas are easily visualized and readily accessible. Several studies have shown advantages of the laparoscopic approach to myomectomy. Mais and colleagues randomized 20 patients undergoing myomectomy to laparoscopy and 20 patients to laparotomy. The laparoscopy group had lower postoperative pain as well as a greater number of patients who were analgesia-free on postoperative day 2, discharged home by postoperative day 3, and fully recovered on postoperative day 15.72 Among a group of 131 patients randomly assigned to myomectomy via laparoscopy or laparotomy, Seracchioli and colleagues found that laparoscopic myomectomy is associated with lower intraoperative blood loss and shorter postoperative length of stay in the hospital. Moreover, no significant difference in subsequent fecundability, spontaneous miscarriage rate, preterm delivery rate, or cesarean section rate was found between the groups. A lower incidence of postoperative febrile morbidity was yet another advantage found in this study.67 Adhesion formation was evaluated in a retrospective study of 28 patients who underwent laparoscopy or laparotomy for myomectomy followed by a second-look laparoscopy.73 A lower incidence of adhesion formation was noted in patients that initially underwent a laparoscopic approach to their myomectomy. Similar observations were made in two other studies.74,75
Figure 46-6 The myoma has been almost completely enucleated. Vessels at the base of the myoma should be cauterized. (Courtesy of Dr. T. Falcone.)
Disadvantages of laparoscopic myomectomy include the lack of opportunity to palpate the uterus intraoperatively, resulting in the potential for a higher rate of subsequent recurrence of myomas,76,77 a finding that is supported by several studies and refuted by others.78 An additional disadvantage is operatordependent and involves the technical difficulty in repairing the enucleated leiomyomas, with a potential risk for uterine rupture during future pregnancies if improperly closed. Technical Considerations
Laparoscopic myomectomy is usually performed with the standard three to four ports. Dilute vasopressin, although not approved by the U.S. Food and Drug Administration (FDA) for this indication, is diluted 20 units in 100 mL of normal saline solution and injected into the myoma. An incision is then made into the myoma and enucleated bluntly (Figs. 46-5 and 46-6). After
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Figure 46-7 A large myometrial defect is left behind. This requires closure with two or three layers of delayed absorbable sutures. (Courtesy of Dr. T. Falcone.)
Figure 46-9 A left hypogastric arteriogram. The superior gluteal artery is the large vessel sweeping out horizontally to the patient’s left; the inferior gluteal artery is the large, S-shaped vertical branch, and the uterine artery is the small, vertical, slightly redundant branch lateral to the inferior gluteal. The redundancy is a key identifying feature, as well as its hypervascularity in the setting of fibroids. The bones are visible on this injection. (Courtesy of Dr. James Newman, Department of Diagnostic Radiology, Cleveland Clinic.)
Figure 46-8 The myometrial defect is tightly closed. (Courtesy of Dr. T. Falcone.)
enucleation, the defect (Fig. 46-7) is closed in two or three layers, typically a deep layer and then a seromuscular layer. Intracorporeal or extracorporeal knot tying are both acceptable. This step is the most critical part of a laparoscopic myomectomy, and the defect should be closed tightly (Fig. 46-8).
UTERINE ARTERY/LEIOMYOMA EMBOLIZATION
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Uterine artery embolization (UAE) or uterine fibroid embolization (UFE) is a minimally invasive alternative to hysterectomy and myomectomy that has been applied to the treatment of symptomatic leiomyomas (Figs. 46-9 to 46-12). UAE was initially developed for the control of pelvic hemorrhage and has been utilized for the primary treatment of leiomyomas since 1995.79 It has been associated with positive clinical outcomes and a high
Figure 46-10 A catheter has been selectively placed into the left uterine artery, and only the left uterine artery is opacified here. Note the tortuosity and redundancy of the artery just below the catheter tip, the artery’s short horizontal, medially directed segment with cervical and vaginal branches arising from it, before the artery turns cephalad and ascends along the lateral border of the uterine body. Also note the hypertrophic uterine fundal branches supplying the fibroids in the left uterine body. The most cephalic branches ultimately follow the broad ligament out laterally toward the ovary (typically not seen, because majority of flow is toward the fibroids, and ovary is typically [96%] supplied redundantly by ipsilateral ovarian artery). The catheter position shown here is considered acceptable for embolization. The great majority of injected embolization particles will travel to the perifibroidal plexus and initiate infarction of the fibroid in situ. (Courtesy of Dr. James Newman, Department of Diagnostic Radiology, Cleveland Clinic.)
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Figure 46-11 Selective arteriogram of the right uterine artery, same patient. The left uterine artery has been embolized just a few minutes earlier. Note how the opacified bladder shows an extrinsic impression on its roof, secondary to fibroids in the lower uterine segment. Note again the redundant vertical course of the right uterine artery below the catheter tip, the short, medially directed medial segment, and the ascending uterine fundal segment with hypertrophied fibroidal branches. (Courtesy of Dr. James Newman, Department of Diagnostic Radiology, Cleveland Clinic.)
fluoroscopic guidance. Typically, UFE is performed with the patient under conscious sedation.31 Postembolization follow-up consists of clinical evaluation as well as a follow-up MRI to assess and monitor the final resulting volume of leiomyomas and the uterus. The degeneration and devascularization of leiomyomas can be visualized on MRI as increased signals on T1- and decreased signals on T2-weighted images.82–84 After UFE, the size of leiomyomas can continue to decrease for 1 year or more. The high rate of patient satisfaction80 is due to the improvements in menorrhagia and pressure symptoms as well as pain relief experienced by a high percentage of women undergoing UFE. It is important to note that successful pregnancies have occurred after this procedure.85,86 There is a recognized risk of inducing premature ovarian failure in older women. Several studies have shown an increased risk of intrauterine growth restriction and placentation problems in pregnancies after UFE. This procedure is not considered the treatment of choice for symptomatic leiomyomas in patients who desire future fertility. Complications of UFE include angiographic-related problems,31 allergic reactions,87 perforation of the uterus,88 and infection.83,87 If the collateral blood supply to the ovary is embolized, infertility, amenorrhea, and premature menopause are potential risks.81,89 Sciatic nerve injury leading to buttock claudication is a recognized potential complication of UFE.88 Deep venous thrombosis and pulmonary embolus are rare risks, as is death.88,90,91 The incidence of death with UFE is reported to be 3/10,000 compared with the 1/1000 rate from hysterectomy.92 Postembolization syndrome is a relatively common occurrence and consists of nausea, vomiting, pain, and a temporary increased white blood cell count after the procedure. This syndrome affects most patients to some extent in the first 48 hours after the procedure, but is severe in approximately 15% of those who undergo UFE.93
HIGH-INTENSITY MRI-GUIDED FOCUSED ULTRASOUND THERAPY
Figure 46-12 The same arteriogram as Figure 45-11, with the bones electronically suppressed. The tortuosity in the horizontal segment precluded further catheter advancement, and embolization was successfully carried out from the catheter position shown here. (Courtesy of Dr. James Newman, Department of Diagnostic Radiology, Cleveland Clinic.)
rate of patient satisfaction. Success rates of over 90% have been reported.80,81 Decreases in the size of the uterus and dominant leiomyomas of 45% (from baseline volumes) have been reported.25 Pre-embolization imaging with MRI aids in precisely locating the position of leiomyomas before the procedure. Embolization of the uterine arteries with polyvinyl alcohol or tris-acryl gelatin microspheres involves femoral artery catheterization under
Recent advances in the developing field of therapeutic ultrasound have led to the development of high-intensity focused ultrasound surgery (HIFU). HIFU unites two technologies, therapeutic ultrasound and diagnostic MRI, and provides a combined noninvasive procedure that aims to destroy leiomyoma tissue in a precise and controlled fashion. By placing an ultrasound transducer on the abdomen of a patient and focusing the ultrasound energy at a specific, controllable depth and position, leiomyoma tissue is destroyed within the focal zone (Fig. 46-13). The therapeutic ultrasound effect is monitored by MRI, which precisely records the temperature elevation from the heat generated over time. Once the temperature reaches 57oC for 1 second, tissue is rapidly destroyed within the focal zone. Tissue within 2 to 3 mm of the focal zone is unaffected due to the very precise demarcation between normal and destroyed tissue. Magnetic resonance imaging-guided focused ultrasound surgery as a therapy for leiomyoma treatment received FDA approval in October 2004. The ExAblate System (InSightec, Dallas) is the first medical device approved for the treatment of leiomyomas as its primary indication. General patient selection criteria include leiomyomas between 4 and 10 cm, maximum depth of subcutaneous tissue to the leiomyoma less than 12 cm, completion of
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Magnet bore
cm
Fibroid
Coupling pad Positioning system
Fibroid
Transducer Transducer
Degassed water Patient table
Pelvic coil
Figure 46-13 Left, Side-view diagram of the focused ultrasound system and patient positioning. Right, Sagittal T2-weighted fast SE MR image obtained with the patient in position for treatment. (From Clare M. C. Temany, Elizabeth A. Stewart, Nathan McDannold, Bradley J. Quade, Ferenc A. Jolesz, and Kullervo Hynynen. MR Imaging-guided Focused Ultrasound Surgery of Uterine Leiomyomas: A Feasibility Study. Radiology 226:897, 2003.)
childbearing, premenopausal status, and leiomyomas that can be clearly visualized on MRI. Based on results of a 6-month followup study, the mean leiomyoma reduction in volume after HIFU was 13.5 cm3, and the mean volume of nonperfused tissue was 51.2 cm3. Furthermore, 79.3% of patients reported a greater than 10-point reduction in symptom scores and improvement in quality of life measures on the questionnaire used in the study.94 Adverse events included minor skin burns in 4% of patients, worsening menorrhagia in 4% of patients, hospitalization for nausea in only 1% of patients, and nontargeted sonication of the uterine serosa in 1% of patients.94 There are no randomized clinical trials that have compared this technology with surgical or other radiologic treatment.
CRYOMYOLYSIS
692
Cryomyolysis of uterine leiomyomas has been performed in the past by laparoscopy. In recent years, MRI-guided cryomyolysis has been devised as a less invasive approach. Cryomyolysis involves placement of a 2-cm diameter cryoprobe directly into a uterine leiomyoma. After the cryoprobes are advanced and placed into position, cryomyolysis is then performed by the instillation of cryogenic media. Laparoscopic cryomyolysis for women with leiomyomas as well as a combination of abnormal uterine bleeding, pelvic pain/pressure, and/or urinary frequency was shown to be effective in a study of 20 patients.95 Magnetic resonance imaging-guided cryomyolysis was devised as a less invasive and more precise approach. MRI can be employed to accurately visualize ice ball formation, which eventually encompasses the leiomyomas, appearing black due to the slow or absent hydrogen ion spins of water molecules in the ice. A report of MRI-guided cryomyolysis used to treat leiomyomas in 10 patients showed MRI evidence of marked uterine volume reduction 48 to 334 days after the procedure. The mean volume reduction was 65%. All patients reported improvement of symptoms, whether they were due to bleeding or pressure. One
patient had uterine bleeding for 2 months after the procedure, with subsequent spontaneous resolution. Another patient had a residual submucosal leiomyoma that had to be resected hysteroscopically at a later date. Complications included a patient with laceration of a serosal vessel covering a leiomyoma, which required a laparotomy and open myomectomy for repair. Another complication was peroneal nerve involvement and a mild footdrop that resolved over several months. Nausea and mild abdominal discomfort that was relieved by NSAIDs were reported as minor complications.96 Another study of 14 women evaluated the efficacy of 2 months of pretreatment with GnRH agonist before laparoscopically directed cryomyolysis.97 The GnRH agonist was discontinued immediately before the procedure. Four months after cryomyolysis, the follow-up MRI showed a mean volume decrease of 10% among the frozen leiomyomas, whereas other uterine tissue returned to their size before GnRH agonist treatment.
LAPAROSCOPIC UTERINE ARTERY LIGATION Laparoscopic uterine artery ligation is yet another potential option for women who opt to preserve their uteri. A study comparing this technique to UAE suggests that the uterine volume was slightly reduced at 3 months and stabilized at 6 months, with an average volume reduction of 58.5%.98 The authors concluded that both laparoscopic uterine artery ligation and UAE are reasonable alternatives to hysterectomy.
CONCLUSION Our knowledge regarding the pathogenesis, genetics, and treatment options for uterine leiomyomas has expanded exponentially over the past decade. Science is poised for exciting new discoveries to target specific patients for therapy based on their unique genetic factors and to better employ minimally invasive techniques based on the latest technology with impressive effectiveness.
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Chapter 46 Uterine Leiomyomas Approximately $5 billion is currently spent annually in the diagnosis and treatment of uterine leiomyomas. This has resulted in a recent commitment to expanded public and industrial research funding for the development of innovative treatment modalities. The goal of treating leiomyomas in the future will evolve from hysterectomy or myomectomy to medical therapies targeting tissue-specific promoters to alleviate symptoms without side effects. Most if not all of the compelling new therapies will stem from a better understanding of the physiologic factors contributing to leiomyoma development. Looking forward, future strategies will likely be based on targeted pharmacologic intervention and effective preventive strategies.
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Uterine leiomyomas are the most common benign pelvic tumors found in women. At least 50% of uterine leiomyomas are asymptomatic. The most common types of leiomyomas associated with heavy bleeding are intramural or submucosal myomas. The relationship between infertility and myomas is unclear. Many women with myomas have normal fertility. The most common types of leiomyomas associated with heavy bleeding are intramural or submucosal myomas. Leiomyomas are defined as monoclonal proliferations of benign smooth muscle. Each monoclonal myoma may be associated with various chromosomal translocations, duplications, and deletions. Myomas are responsive to estrogen and progesterone. Serum concentrations of circulating estrogen or progesterone have not been found to be increased. Studies have shown that, in comparison with the normal myometrium, myomas have an increased concentration of estrogen and progesterone receptors.
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The stimulation of myoma expansion may be a function of the suppression of apoptosis by progesterone. In patients with a menstrual abnormality oral contraceptives have been used successfully and the presence of a leiomyoma is not considered a contraindication. The important concept in the management of leiomyomas is that intervention is not required in asymptomatic women. Rapid growth of leiomyoma was considered a potential sign of malignancy. However this sign in isolation of other manifestations is not considered prognostic of a sarcoma. Surgical treatment specifically for infertility is indicated if there is distortion of the uterine cavity. Maximum reduction of the mean uterine volume occurs within 3 months of GnRH agonist administration. The decrease in volume is usually in the range of 40% to 80%. Add-back therapy with progestins alone will impede the effectiveness of the GnRH agonist in reducing uterine size. SERMs such as raloxifene do not effectively decrease myoma size in premenopausal women. Selective progesterone receptor modulators seem effective in decreasing myoma size. Myomectomy is the surgery of choice for treating women with symptomatic myomas in those who desire to preserve fertility or to otherwise keep their uteri. Incisions placed on the anterior aspect of the uterus seem to be associated with fewer adhesions than incisions placed in the posterior part of the uterus. Laparoscopic approach to myomectomy has been shown to be as effective as laparotomy if the same principles such as a tight myometrial closure are applied. Uterine artery embolization or uterine fibroid embolization (UFE) is an effective technique for the treatment of the pain or menstrual problems associated with leiomyomas.
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43. Fleischer AC: Color Doppler sonography of uterine disorders. Ultrasound Q 19:179–183, 2003. 44. Baramki TA: Hysterosalpingography. Fertil Steril 83:1595–1606, 2005. 45. Mueller GC, Gomez J, Carlos RC: Diagnostic imaging and vascular embolization for uterine leiomyomas. Semin Reprod Med 22:131–142, 2004. 46. Lee JK, Gersell DJ, Balfe DM, et al: The uterus: In vitro MR-anatomic correlation of normal and abnormal specimens. Radiology 157:175–179, 1985. 47. Yamashita Y, Torashima M, Takahashi M, et al: Hyperintense uterine leiomyoma at T2-weighted MR imaging: Differentiation with dynamic enhanced MR imaging and clinical implications. Radiology 89:721–725, 1993. 48. Okizuka H, Sagimura K, Takemori M, et al: MR detection of degenerating uterine leiomyomas. J Comput Assist Tomogr 17:760–766, 1993. 49. Friedman AJ, Label SM, Rein MS, Barbieri RL: Efficacy and safety considerations in women with uterine leiomyomas treated with gonadotropinreleasing hormone agonists: The estrogen threshold hypothesis. Am J Obstet Gynecol 163:1114–1119, 1990. 50. Shozu M, S. H., Segawa T, et al: Inhibition of in situ expression of aromatase p450 in leiomyoma of the uterus by leuprolide acetate. J Clin Endocrinol Metab 86:5405–5411, 2001. 51. De Leo V, Morgante G, La Marca A, et al: A benefit-risk assessment of medical treatment for uterine leiomyomas. Drug Safety 25:759–779, 2002. 52. Stovall TG, Muneyyirici-Delale O, Summitt RL, Scialli AR: GnRH agonist and iron versus placebo and iron in the anemic patient before surgery for leiomyomas: A randomized controlled trial. Leuprolide Acetate Study Group. Obstet Gynecol 86:65–71, 1995. 53. Dawood M, Lewis V, Ramos J: Cortical and trabecular bone mineral content in women with endometriosis: Effect of gonadotropin-releasing hormone agonist and danazol. Fertil Steril 52:21–26, 1998. 54. Carr BR, Marshburn PB, Weatherall PT, et al: An evaluation of the effect of gonadotropin releasing hormone analog and medroxyprogesterone acetate on uterine leiomyoma volume by MRI: A prospective randomized double blind placebo controlled cross over trial. J Clinic Endocrinol Metab 76:1217–1223, 1993. 55. Guetta V, Lush RM, Figg WD, et al: Effects of the antiestrogen tamoxifen on low-density lipoprotein concentrations and oxidation in postmenopausal women. Am J Cardiol 76:1072–1073, 2005. 56. Delmas PD, Bjarnason NH, Mitlak BH, et al: Effects of raloxifene on bone mineral density, serum cholesterol concentrations, and uterine endometrium in postmenopausal women. NEJM 337:1641–1647, 1997. 57. Fuchs-Young R, Howe S, Hale L, et al: Inhibition of estrogen-stimulated growth of uterine leiomyomas by selective estrogen receptor modulators. Mol Carcinog 17:151–159, 1996. 58. Walker CL, Burroughs K, Davis B, et al: Preclinical evidence for therapeutic efficacy of selective estrogen receptor modulators for uterine leiomyoma. J Soc Gynecol Invest 7:249–256, 2000. 59. Porter KB, Tsibris JC, Porter GW, et al: Effects of raloxifene in a guinea pig model for leiomyomas. Am J Obstet Gynecol 179:1283–1287, 1998. 60. Palomba S, Sammartino A, Di Carlo C, et al: Effects of raloxifene treatment on uterine leiomyomas in postmenopausal women. Fertil Steril 76:38–43, 2001. 61. Palomba S, Orio F, Morelli M, et al: Raloxifene administration of women treated with gonadotropin-releasing hormone agonist for uterine leiomyomas: Effects on bone metabolism. J Clin Endocrinol Metab 87: 4476–4481, 2002. 62. Palomba S, Orio F, Morelli M, et al: Raloxifene administration in premenopausal women with uterine leiomyomas: A pilot study. J Clin Endocrinol Metab 87:3603–3608, 2002. 63. Palomba S, Rosso T, Orio F, et al: Effectiveness of combined GnRH analogue plus raloxifene administration in the treatment of uterine leiomyomas: A prospective, randomized, single-blind, placebo-controlled trial. Hum Reprod 17:3213–3219, 2002. 64. Chwalisz K, De Manno D, Garg R, et al: Therapeutic potential for the selective progesterone receptor modulator asoprisnil in the treatment of leiomyomata. Semin Reprod Med 22:113–9.
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Chapter 46 Uterine Leiomyomas 65. Elger W, Bartley J, Schneider B, et al: Endocrine-pharmacological characterization of progesterone antagonists and progesterone receptor modulators (PRMs) with respect to PR-agonistic and antagonistic activity. Steroids 65:713–723, 2000. 66. Chwalisz K, Elger W, McCrary K, et al: Reversible suppression of menstruation in normal women irrespective of the effect on ovulation with the novel selective progesterone receptor modulator (SPRM) J867. J Soc Gynecol Invest 9 (Suppl): 2002. 67. Seracchioli R, Rossi S, Govoni F, et al: Fertility and obstetric outcome after laparoscopic myomectomy of large myomata: A randomized comparison with abdominal myomectomy. Hum Reprod 15: 2663–2668, 2000. 68. Wilcox LS, Koonin LM, Pokras R, et al: Hysterectomy in the United States, 1988–1990. Obstet Gynecol 83:549–555, 1994. 69. Ribeiro SC, Ribeiro RM, Santos NC, Pinotti JA: A randomized study of total abdominal, vaginal and laparoscopic hysterectomy. Int J Gynecol Obstet 83:37–43, 2003. 70. Reich H: Laparoscopic hysterectomy. Surgical Laparoscopy and Endoscopy 2:85–8, 1992. 71. ACOG: Surgical Alternatives to Hysterectomy in the Management of Leiomyomas. Compendium of Selected Publications. ACOG Practice Bulletin no.16, May 2000, pp 776–784. 72. Mais V, Ajossa S, Guerriero S, et al: Laparoscopic versus abdominal myomectomy: A prospective, randomized trial to evaluate benefits in early outcome. Am J Obstet Gynecol 174:654–658, 1996. 73. Bulletti C, Polli V, Negrini V, et al: Adhesion formation after laparoscopic myomectomy. J Am Assoc Gynecol Laparosc 3:533–536, 1996. 74. Takeuchi H, Kinoshita K: Evaluation of adhesion formation after laparoscopic myomectomy by systematic second-look microlaparoscopy. J Am Assoc Gynecol Laparosc 9:442–446, 2002. 75. Dubuisson JB, Fauconnier A, Chapron C, Kreiker G, Norgaard C: Second look after laparoscopic myomectomy. Hum Reprod 13:2102–2106, 1998. 76. Doridot V, Dubuisson J-B, Chapron C, et al: Recurrence of leiomyomata after laparoscopic myomectomy. J Am Assoc Gynecol Laparosc 8: 495–500, 2001. 77. Nezhat FR, Roemisch M, Nezhat CH, et al: Recurrence rate after laparoscopic myomectomy. J Am Assoc Gynecol Laparosc 5:237–240, 1998. 78. Rossetti A, Sizzi O, Soranna L, et al: Long-term results of laparoscopic myomectomy: Recurrence rate in comparison with abdominal myomectomy. Hum Reprod 16:770–774, 2001. 79. Ravina JH, Herbreteau D, Ciraru-Vigneron N, et al: Arterial embolisation to treat uterine myomata. Lancet 346:671–672, 1995. 80. Worthington-Kirsch RL, Popky GL, Hutchins FL Jr: Uterine arterial embolization for the management of leiomyomas: Quality-of-life assessment and clinical response. Radiology 208:625–629, 1998. 81. Spies JB, Ascher SA, Roth AR, et al: Uterine artery embolization for uterine leiomyoma. Obstet Gynecol 98:29–34, 2001. 82. Burn PR, McCall JM, Chinn RJ, et al: Uterine fibroleiomyoma: MR imaging appearances before and after embolization of uterine arteries. Radiology 214:729–734, 2000.
83. deSouza NM, Williams AD: Uterine arterial embolization for leiomyomas: Perfusion and volume changes at MR imaging and relation to clinical outcome. Radiology 222:367–374, 2002. 84. Jha RC, Ascher SM, Imaoka I, Spies JB: Symptomatic fibroleiomyomata: MR imaging of the uterus before and after uterine arterial embolization. Radiology 217:228–235, 2000. 85. Walker WJ, Pelage JP: Uterine artery embolisation for symptomatic fibroids: Clinical results in 400 women with imaging follow up. BJOG 109:1262–1272, 2002. 86. Watson GM, Walker WJ: Uterine artery embolisation for the treatment of symptomatic fibroids in 114 women: Reduction in size of the fibroids and women’s views of the success of the treatment. BJOG 109:129–135, 2002. 87. Spies JB, Ascher SM, Roth AR, et al Complications after uterine artery embolization for leiomyomas. Obstet Gynecol 100:873–880, 2002. 88. Goodwin SC, Wong GC: Uterine artery embolization for uterine fibroids: A radiologist’s perspective. Clin Obstet Gynecol 44:412–424, 2001. 89. Chrisman HB, Saker MB, Ryu RK, et al: The impact of uterine fibroid embolization on resumption of menses and ovarian function. J Vasc Intervent Radiol 11:699–703, 2000. 90. Lanocita R, Frigerio L, Patelli G, et al: A fatal complication of percutaneous transcatheter embolization for the treatment of fibroids. Second International Symposium on Embolization of Uterine Myomata/Society for Minimally Invasive Therapy, 11th International Conference, Boston, 1999. 91. de Blok S, de Uries C, Prinssen H, et al: Fatal sepsis after uterine artery embolization with microspheres. J Vasc Intervent Radiol 14:779–783, 2003. 92. Wingo PA, Hunter C, Rubin GL, et al: The mortality risk associated with hysterectomy. Am J Obstet Gynecol 152:803–808, 2000. 93. Hurst BS, S. D., Matthews ML, Marshburn PB: Uterine artery embolization for symptomatic uterine myomas. Fertil Steril 74: 855–869, 2000. 94. Stewart EA, Gedroyc W, Tempany C, et al: Focused ultrasound treatment of uterine fibroid tumors: Safety and feasibility of a noninvasive themoablative technique. Am J Obstet Gynecol 189:48–54, 2003. 95. Zupi E, Piredda A, Marconi D, et al: Directed laparoscopic cryomyolysis: A possible alternative to myomectomy and/or hysterectomy for symptomatic leiomyomas. Am J Obstet Gynecol 190:639–643, 2004. 96. Cowan BD: Myomectomy and MRI-directed cryotherapy. Semin Reprod Med 22:143–148, 2004. 97. Zriek TG, Rutherford TJ, Palter SF, et al: Cryomyolysis, a new procedure for the conservative treatment of uterine fibroids. J Am Assoc Gynecol Laparosc 5:33–38, 1998. 98. Park KH, Kim JY, Shin JS, et al: Treatment outcomes of uterine artery embolization and laparoscopic uterine artery ligation for uterine myoma. Yonsei Med J 44:694–702, 2003.
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Section 7 Reproductive Surgery Chapter
47
Tubal Disease Raedah Al-Fadhli and Togas Tulandi
INTRODUCTION Tubal disease is one of the most common causes of infertility and is almost always preventable. It is usually the result of sexually transmitted disease; therefore, prevention is the key intervention for this cause of infertility. In the past, the surgical management of tubal disease often differentiated the skilled infertility expert from his peers. The advent of in vitro fertilization (IVF) has greatly diminished the role of reconstructive tubal surgery for severe forms of tubal disease but remains a viable option for mild to moderate disease. The quest by couples to have a natural conception with reduced risks of multiple pregnancies has made this approach appealing to many couples. This chapter describes the classification and evaluation of tubal disease, including commonly used radiographic and surgical techniques. Special attention is paid to the management of hydrosalpinges in women undergoing IVF. Various treatment options for these conditions are also discussed.
Hysterosalpingography HSG is a contrast study of the fallopian tubes and the uterine cavity. It is widely used because it is simple, cost-effective, and associated with minimal side effects. Distal tubal blockage is usually associated with a hydrosalpinx. A potential limitation of HSG is tubal spasm, which can give a false impression of proximal or cornual occlusion. The incidence of false-positive
ETIOLOGY AND CLASSIFICATION Tubal disease accounts for 25% to 35% of female infertility. The most common cause of tubal damage is pelvic inflammatory disease (PID) (Fig. 47-1A; Table 47-1). Furthermore, the incidence of subsequent tubal occlusion is proportional to the number of PID episodes.1 Other causes of tubal damage are ectopic pregnancy and iatrogenic tubal sterilization. A detailed discussion of the infectious causes of infertility is given in Chapter 33. In a smaller scale, in utero exposure to diethylstilbestrol (DES) has been implicated to cause fallopian tube abnormalities, such as foreshortened, sacculated, or convoluted tube.2 The fallopian tube can be occluded at multiple sites. However, it is common to classify the blockage as proximal, midtubal, or distal tubal. The reproductive performance after reconstructive tubal surgery depends on the extent and the location of tubal damage. Women with extensive tubal damage will have a low chance of conceiving and IVF would provide a better chance.
A
EVALUATION OF TUBAL DISEASE There are multiple tests to evaluate tubal condition, including hysterosalpingography (HSG), sonohysterosalpingography, laparoscopy, and salpingoscopy. Serology for Chlamydia has also been advocated. Each diagnostic test has its own limitations.
B Figure 47-1 A, Patient with chronic pelvic inflammatory disease and (B) perihepatic adhesions (Fitz-Hugh–Curtis syndrome), usually related to previous gonorrhea or chlamydia infection.
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Section 7 Reproductive Surgery advantage of this procedure is that it does not allow evaluation of the whole abdominal or pelvic cavity. The main concern of transhydrolaparoscopy is bowel injury (about 0.65%).8
Table 47-1 Etiology of Tubal Disease Causes
Frequency
Pelvic inflammatory disease
50%
Previous pelvic surgery
27%
Salpingoscopy
results is estimated to be 50%.3 Hurd and colleagues reported that an apparent unilateral obstruction might be resolved in more than 50% of the patients by rotating the patient in a direction that places the obstructed tube in more inferior position.4 Pregnancy can occur after HSG. Perhaps, this is due to dislodging of a mucus plug or necrotic debris from the tubal lumen. In a randomized study, the pregnancy rate in women with patent tubes was 64% after HSG using oil-soluble contrast medium and 56% after the use of water-soluble contrast medium.5
This is an endoscopic approach to visualize the intraluminal part of the fallopian tube. The procedure is usually done with a rigid salpingoscope.9 The salpingoscope is introduced into the abdominal cavity through the operating channel of the laparoscope. An atraumatic forceps in the secondary port is used to grasp and align the ampullary segment of the tube. The salpingoscope is then slowly advanced into the tube from the fimbrial end. The inner portion of the tube is visualized until the tubal ostium. Saline solution is used as the distension medium. Salpingoscopic findings can be classified into five grades. Grade I refers to normal mucosal folds; in grade II, major folds are separated and flattened; grade III refers to the presence of a focal lesion (adhesions, polyps, or strictures); in grade IV, there are extensive lesions with either preservation or loss of the mucosal folds; and grade V is complete loss of the mucosal folds. The cumulative pregnancy rate is inversely related to the degree of tubal damage.10,11 Salpingoscopy can also be performed through transvaginal hydrolaparoscopy.12
Sonohysterosalpingography
Falloposcopy
Sonohysterosalpingography, also referred to as hystero-contrastsonography or HyCoSy, is an alternative to HSG. The technique involves introduction of fluid into the uterine cavity. This is an outpatient procedure that usually lasts about 20 minutes. Saline solution is an echo-free contrast medium for assessment of the uterine cavity. The fallopian tubes can be evaluated by another contrast medium, such as air, albumin with micro-air bubbles, or galactose with micro-air bubbles. This contrast medium outlines the fallopian tube, giving a hyperechoic appearance.6 In a meta-analysis that included more than 1000 women, a similar rate of detecting tubal pathology was reported between sonohysterosalpingography and HSG or laparoscopy.7 Sonohysterosalpingography showed a false tubal occlusion in 10% of cases when compared to laparoscopy and chromopertubation. When sonohysterosalpingography was compared to HSG, a falsepositive rate of 13% was found.
This transvaginal endoscopic technique13 involves the use of an extremely narrow microendoscope (0.45 to 0.5 mm in diameter) for transcervical tubal cannulation using local anesthesia. The entire fallopian tube can be visualized. There are two techniques. The first (coaxial technique) is a hysteroscopic approach where a flexible guidewire enclosed in a soft catheter is introduced into the uterotubal ostium. The catheter and the guidewire are slowly advanced for a distance of approximately 12 cm or until resistance is encountered. The guidewire is removed and the falloposcope is introduced through the catheter. In a multicenter trial, it was found that 40% of normal tubes diagnosed on HSG had abnormalities observed on falloposcopy.14 This coaxial approach lacks a uniform scoring system and the image quality is poor. The second technique involves the use of a linear everting catheter by a transvaginal approach that does not require hysteroscopy.15 This procedure is also limited by image quality. Neither procedure is commonly used.
Iatrogenic posttubal sterilization Endometriosis Congenital anomalies
1–3% 7–14% Rare
Laparoscopic Procedures Laparoscopic Chromopertubation
This has been the gold standard for investigating tubal patency. Furthermore, laparoscopy permits direct visualization of the whole peritoneal cavity, including other pathology such as perihepatic adhesions (see Fig. 47-1B). Details of this procedure are reviewed in Chapter 44. Transhydrolaparoscopy
698
This technique involves the use of a culdoscopic approach and the use of a small endoscope to explore the pelvic cavity. It is performed with the patient in the dorsal lithotomy position. Using saline solution as a distension medium, the posterior aspect of the uterus and tubo-ovarian structures are inspected. The saline instillation continues throughout the procedure to float the tubes and the ovaries. The advantage of this procedure is that it can potentially be used in an office setting. The dis-
MANAGEMENT OF TUBAL INFERTILITY Depending on the type and degree of tubal dysfunction, various methods of treatment are available. The results depend on patient age, ovarian function, and the presence or absence of male fertility factor. Patients with bilateral multisite tubal obstruction or with severe pelvic adhesions will benefit from IVF rather than surgery.
Basic Principles of Tubal Surgery Most reproductive surgery is performed by laparoscopy. Compared to open surgery, laparoscopic surgery is a low-risk procedure, usually does not require hospitalization, and is associated with less postoperative pain than laparotomy. Nevertheless, it requires gentle handling of the tissue, good hemostasis, and careful dissection of the tissue.
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Chapter 47 Tubal Disease At operative laparoscopy, dissection is better performed using sharp dissection with minimal use of electrical or laser energy. Thermal damage is associated with higher risk of adhesion formation. The use of sutures should be limited as well. However, if needed the suture material should be fine and nonreactive (e.g., 6-0 polyglactin or polyglycolic acid). The sutures should be placed without strangulating the tissue. Hemostasis is achieved using microbipolar forceps.
Proximal Tubal Occlusion Proximal tubal occlusion is found in 10% to 25% of women with tubal disease. It is mainly due to salpingitis isthmica nodosa. Other causes of failed filling of the tubes are chronic pelvic infection, congenital malformation, and tubal spasm. Tuberculosis may cause varying degrees of tubal damage from minimal to extensive proximal tubal block.16 The thick muscular wall of the proximal tube, with its physiologic sphincter and its narrow lumen, makes it susceptible for “obstruction” by mucous debris.17 The therapeutic approach for proximal tubal occlusion includes selective salpingography and tubal catheterization under fluoroscopy, hysteroscopic transcervical tubal cannulation, and resection and reanastomosis. Selective Salpingography and Tubal Catheterization under Fluoroscopy
This is an established procedure for diagnosis and treatment of proximal tubal occlusion (Fig. 47-2). The procedure is performed by passing a catheter through the cervix into the proximal tubes. Radiocontrast medium is then injected under fluoroscopic guidance. Similar to HSG, the pressure induced by the injection may help in overcoming the obstruction. Otherwise, a guidewire is introduced into the fallopian tube to overcome the obstruction. Several catheter systems with different lumen sizes are available. A three-catheter system developed by BEI Medical Systems (Hackensack, N.J.) consists of a cervical catheter, an ostial catheter for selective salpingography, and a cornual catheter for tubal catheterization.
Figure 47-3 The ostial catheter is advanced into the uterine cornua and radiopaque contrast medium is injected into the tube.
Table 47-2 Pregnancy Rates after Selective Tubal Catheterization Technique
Pregnancy Rate (%)
Ectopic Rate (%)
Fluoroscopic technique
50%
2–9%
Hysteroscopic technique
50%
5%
The procedure is usually performed under paracervical block with or without intravenous sedation. The first catheter is introduced through the cervix into the uterine cavity. A balloon is inflated to occlude the cervix. The second (ostial) catheter is then passed through the central lumen of the cervical catheter and advanced to the uterine cornua. Radiopaque contrast medium is injected into the tube directly (Fig. 47-3). Repeated radiographs are done to demonstrate the filling of the tube proximally and distally and whether peritoneal spillage occurs. If selective salpingography is not successful, the third (uterine cornual) catheter with a guidewire is used. Threading of an atraumatic guidewire through the catheter into the ostium and the isthmus (tubal cannulation) unblocks the obstruction. In most cases (85%), the tubal occlusion can be overcome. Yet, reocclusion rate is high (30%). Tubal perforation can occur in 3% to 11% of cases; however, it heals spontaneously without any further treatment. The pregnancy rate after selective salpingography and tubal catheterization is about 50% (Table 47-2). The procedure can be repeated if the tubes reocclude. If the procedure fails, patients can be offered IVF or reconstructive tubal surgery. Hysteroscopic Transcervical Tubal Cannulation
Figure 47-2 Bilateral cornual blockage seen at the time of selective tubal catheterization.
This hysteroscopic procedure is similar to selective salpingography and tubal catheterization. This procedure typically uses a Novy cornual cannulation set (Cook Ob/Gyn, Spencer, Ind.). A catheter is introduced into the working channel of an operative hysteroscope. The catheter is then advanced toward the tubal orifice and wedged against the ostium (Fig. 47-4). Dilute indigo carmine is then injected while observing laparoscopically for
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Section 7 Reproductive Surgery spillage from the fimbriated end of the tube. If there is no spill an inner catheter with a guidewire is then introduced. The guidewire is introduced through the uterotubal junction and then into the tube. Only then is the inner catheter introduced. No resistance should be met. The guidewire is then removed and dilute indigo carmine is injected. Microsurgical Resection and Anastomosis
The indications for microsurgical technique are failed tubal cannulation or proximal tubal occlusion due to salpingitis isthmica nodosa. The procedure is done by either laparotomy or laparoscopy. Both techniques are similar. First, dilute solution of vasopressin (0.2 units/mL of saline solution) is injected into the uterine cornual junction. Vasoconstriction will occur, and the occluded part of the tube is circumferentially incised from the myometrium. Hemostasis is secured using microbipolar forceps. The tube is transected with microscissors at 2-mm intervals until patency is reached, as indicated by the passage of methylene blue dye that is injected into the uterine cavity. The edges of the transected tube are examined under the microscope or close-contact laparoscope. Depending on the laparoscope and the distance between the end of the scope and
Figure 47-4 Hysteroscopic view of a primary rigid catheter that is curved toward the tubal ostia.
the tissue, magnification up to 10-fold can be obtained. The two cut ends of the tube are approximated with several interrupted sutures of 6-0 polyglactin in the mesosalpinx. Three to four interrupted 7-0 sutures are then placed in the mucosa and muscularis layers circumferentially. The pregnancy rate following cornual anastomosis is approximately 50% (Table 47-3). A metaanalysis of different techniques found that the pregnancy rate after microsurgical repair of cornual obstruction is 58.9%, with an ectopic pregnancy rate of 7.4 %.25 Most patients choose IVF after failed cannulation techniques rather than a surgical approach.
Midtubal Occlusion Tubal sterilization is the most common permanent method of contraception in females. However, more than 1% of sterilized women subsequently seek restoration of their fertility. Data from 2253 women who had tubal sterilization showed a strong correlation between regret and age or change in marital status.26 Reversal of tubal sterilization is the most common indication for surgery of midtubal occlusion (Fig. 47-5). The technique is demonstrated in Figures 47-6 to 47-10. At the beginning of the procedure, the type of occlusion should be reported according to the American Society for Reproductive Medicine (ASRM,
Figure 47-5 ligation.
The middle part of the tube is missing as a result of tubal
Table 47-3 Reproductive Outcome after Surgical Reconstruction of Cornual Occlusion Author
Number of Patients
Method of Surgery
Intrauterine Pregnancies
Ectopic Pregnancies
Ransom & Garcia, 199718
21
Microsurgery
43%
10%
Gillette & Herbison, 198919
42
Microsurgery
56%
Donnez et al, 198720
82
Microsurgery
44%
7%
8
Microsurgery
38%
25%
Gomel, 198322
48
Microsurgery
63%
6%
Diamond, 197923
16 31
Microsurgery Macrosurgery
75% 26%
0% 16%
Grant, 197124
73
Macrosurgery
30%
4%
Lavy et al, 198621
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Chapter 47 Tubal Disease
Figure 47-6 Dilute solution of vasopressin 0.2 units/mL of saline solution is injected into the mesosalpinx adjacent to the occluded part of the tube.
Figure 47-9
Approximation of the tubal portions.
A
Figure 47-7 The proximal end of the tube has been circumferentially incised. Chromopertubation with solution of methylene blue dye indicates the patency of the proximal tubal portion.
B
Figure 47-8 Sutures have been placed in the mucosa and muscular layers of the proximal tube.
Figure 47-10 Tubal anastomosis with the da Vinci robotic device. A, The suture (8-0 Vicryl) is grasped with the right microneedle holder while the left robotic arm grasps the tissue around the proximal anastomosis site. B, The needle is driven into the lumen of the proximal isthmic portion of the tube at the 6 o’clock position. (Pictures courtesy of Dr. T. Falcone.)
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Section 7 Reproductive Surgery Figure 47-11 The American Fertility Society (now the American Society for Reproductive Medicine) classification of tubal occlusion secondary to tubal ligation.
THE AMERICAN SOCIETY CLASSIFICATION OF TUBAL OCCLUSION SECONDARY TO TUBAL LIGATION Patient's Name G
Age
Chart#
Date P
Sp Ab
VTP
Ectopic
Infertile Yes
No
Other Significant History (i.e. surgery, infection,etc.) Sonography
HSG
Photography
Equal Segments Ampullary-ampullary Isthmic-isthmic
Intramural-ampullary Intramural-ampullary
Segmental length (cm) (Extramural)
After Repair Proximal
Laparotomy
EXAMPLES
Unequal Segments Intramural-isthmic
Laparoscopy
Additional Findings:
Distal
Right Left Treatment (Surgical Procedures) ANASTOMOSIS Right
Left
IM-IS
L
Drawing
R
IM-AM IS-IS IS-AM AM-AM Other:
Prognosis for Conception& Subsequent Viable Infant* Excellent (> 75%) Good
(50-75%)
Fair
(25%-50%)
Poor
(< 25%)
*Physician's judgment based upon adnexa with least amount of pathology. Recommended Followup Treatment:
702
formerly the American Fertility Society) classification of tubal occlusion secondary to tubal ligation (Fig. 47-11).27 Isthmic–isthmic tubal anastomosis yields the best pregnancy rate (81%). A similarly high pregnancy rate can be obtained by a laparoscopic approach (Table 47-4). Yoon and coworkers reported a pregnancy rate of 82.8%.28 There has been no randomized trial comparing tubal anastomosis by laparoscopy and laparotomy. Using a life table analysis, Hawkins and colleagues reported that there is no difference in cumulative pregnancy rates between tubal anastomosis by laparoscopy and laparotomy.29 The ectopic pregnancy rates at 18-month follow-
up were 11.8% and 12% in the laparoscopy and laparotomy groups, respectively. The technical difficulty of accomplishing this task by laparoscopy has led to modified versions of the classical twolayer closure. Using a one-stitch technique after laparoscopic tubal anastomosis, Dubuisson and Chapron reported an 87.5% patency rate, 53.1% intrauterine pregnancy rate, and an ectopic pregnancy rate of 6.25%.35 Falcone and colleagues reported on laparoscopic reversal of sterilization with the assistance of a robotic device.36 The daVinci robotic arms can turn 360 degrees and theoretically facilitate laparoscopic suturing (see Fig. 47-10).
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Chapter 47 Tubal Disease Table 47-4 Reproductive Outcome after Reversal of Sterilization Author
Number of Patients
Method
Intrauterine Pregnancies
Ectopic Pregnancies
Gomel, 198322
118
Microsurgery
81%
2%
DeCherney et al, 198330
124
Microsurgery
68%
6%
Paterson, 198531
147
Microsurgery
63%
3%
Lu, 198932
246
Microsurgery
72%
NA
1118
Microsurgery
45%
4%
Bisonnette et al, 199934
102
Laparoscopy
63%
5%
Yoon et al, 200128
202
Laparoscopy
76%
3%
Kim et al, 199733
Only studies with >100 cases were included. NA: Not applicable
Distal tubal damage represents 85% of all cases of tubal infertility. The causes of distal tubal occlusion are PID, pelvic peritonitis, and previous surgery. A standardized method of operative report should be used. There are different scoring systems for distal tubal disease, but the most widely used is the ASRM classification for distal tubal occlusion (Fig. 47-12).27
obstruction of the fallopian tube. Some of these adhesions can appear as minimal agglutination between fimbriae. Gentle division with scissors should be performed. In more severe forms of fimbrial disease, the distal tube may be dilated but patent. The peritoneal adhesive bands are divided by laparoscopic scissors. The procedure can also be done by inserting two graspers into the tubal lumen and then spreading them apart. The procedure is repeated until the fimbria is opened. In severe cases, several interrupted sutures of 6-0 polyglactin to maintain the tubal opening are needed. The results of laparoscopic fimbrioplasty are depicted in Table 47-6.47–50
Salpingostomy
Salpingectomy
The procedure to open a distally occluded tube is called a terminal salpingostomy or salpingoneostomy. A systematic approach is required. First, any adhesions around the tubes should be liberated. The tube is then distended with dilute solution of contrast medium solution, which is injected through the intrauterine cannula (Figs. 47-13 and 47-14). The distended hydrosalpinx is then inspected. An opening on the hydrosalpinx along the avascular white line of the hydrosalpinx is created using laparoscopic scissors (Fig. 47-15). The tube is immobilized by uterine manipulation and with the help of laparoscopic forceps. Eversion of the mucosal flap can be achieved by suturing them in place with interrupted sutures of 6-0 polyglactin (Fig. 47-16). It can also be achieved by light coagulation of the serosal flap approximately 5 mm from the tubal margin. This leads to retraction of the mucosal flap, creating an eversion (Fig. 47-17). Depending on the degree of tubal damage, the overall pregnancy rate after salpingostomy is between 10% and 35% (Table 47-5). A meta-analysis found that increased term pregnancy rates and decreased ectopic rates were associated with microscopic salpingostomy compared to the macroscopic method.37 They also found that intrauterine pregnancy rates were significantly lower with the laparoscopic approach. However, this conclusion was based on the findings of four nonrandomized studies.
Several studies have shown the deleterious effect of hydrosalpinx on the outcome of IVF–embryo transfer (ET).51–55 Perhaps this is due to toxic agents in hydrosalpinx fluid that enter the uterine cavity and impair implantation. Meta-analysis of large retrospective series revealed that the IVF pregnancy rate in women with hydrosalpinx is half of those with tubal infertility of other causes, and the miscarriage rate is double.56,57 In attempt to improve the live birth rate of IVF treatment, it is recommended that the tubes be removed before IVF.58,59 In particular, hydrosalpinges that are visible on ultrasound should be removed. However, it is less certain if removal is necessary for mild cases seen only on HSG. Interestingly, salpingectomy or proximal tubal occlusion of a unilateral hydrosalpinx has been shown to increase spontaneous pregnancy rates.60 Treatment options for hydrosalpinx-related IVF include drainage, salpingostomy, proximal tubal ligation, and salpingectomy. Drainage of hydrosalpinx fluid can be performed by transvaginal needle aspiration under ultrasound guidance, either before the IVF cycle or at the time of oocyte retrieval. The efficacy of this technique is unclear. Furthermore, the fluid tends to reaccumulate after drainage. Salpingostomy is particularly appealing to young women with hydrosalpinx who do not wish their tubes removed because they wish to retain the potential for spontaneous conception. It carries the risk of reocclusion of the hydrosalpinx. Whether the rates of IVF pregnancy after salpingostomy are similar to those after salpingectomy is unknown. Occluding the proximal tube appears to be a reasonable alternative for women with hydrosalpinx undergoing IVF. Pregnancy rates after proximal tubal occlusion are similar to those
Although initial reports showed increased operative time, this may decrease as the technology improves.
Distal Tubal Occlusion
Fimbrioplasty
Fimbrioplasty is release of adhesions covering the fimbriae or the peritoneal bands surrounding the fimbria. The procedure is performed for fimbrial phimosis, which is an incomplete
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Section 7 Reproductive Surgery Figure 47-12 The American Society for Reproductive Medicine classification of distal tubal occlusion.
AMERICAN SOCIETY FOR REPRODUCTIVE MEDICINE CLASSIFICATION OF DISTAL TUBAL OCCLUSION Patient's Name G
Age
Chart#
Date P
Sp Ab
VTP
Ectopic
Infertile Yes
No
Other Significant History (i.e. surgery, infection,etc.) HSG
Sonography
Photography <3 cm 1 1
Tubal wall thickness Tubal wall thickness Mucosal folds at neostomy site Extent of adhesions
None/Filmy 1 1
Prognostic Classification for Terminal Salpingostomy (Salpingoneostomy) LEFT A. Mild
1-3
B. Moderate
9-10
C. Severe
>10
Treatment (Surgical Procedures): Salpingostomy L
Laparotomy
3-5 cm 4 4 Moderately Thickened or Edematous 4 4 35% to 75% Preserved 4 4 Moderate 3 3 Moderately Dense (or Vascular) 2 2
Normal/Thin 1 1 Normal/ >75% Preserved 1 1 None/Minimal/Mild 1 1
Type of adhesions
Laparoscopy
RIGHT
>5 cm 6 6 Thick & Rigid 6 6 35% Preserved Adherent Mucosal Fold 6 6 Extensive 6 6 Dense 4 4
Additional Findings:
R
A. Terminal B. Ampullary
L
Drawing
R
Other:
Prognosis for Conception& Subsequent Viable Infant* Excellent (> 75%) Good (50-75%) Fair (25%-50%) Poor (< 25%) *Physician's judgment based upon adnexa with least amount of pathology. Recommended Followup Treatments:
704
after salpingectomy.61 In one retrospective study of patients undergoing IVF treatment, it was observed that management of hydrosalpinx by laparoscopic salpingectomy or by occluding the proximal tubes yielded statistically similar responses to an IVF–ET cycle.61 Occluding the proximal portion of the tubes is simpler and is a method of choice for women with severe pelvic adhesions. Recently some case reports have suggested a possible role for hysteroscopic tubal occlusion in patients with hydrosalpinx and severe pelvic disease at high risk for complications.
Salpingectomy has been shown to be effective. A randomized trial comparing laparoscopic salpingectomy to no treatment for hydrosalpinx before IVF found the pregnancy and delivery rates (37% and 29%, respectively) in the salpingectomy group were significantly higher than in the nontreated group (24% and 16%, respectively).59 It seems clear that salpingectomy is a worthwhile procedure before IVF.62 The technique of salpingectomy could affect the blood supply to the ovary; caution should be exercised when excising the tube.
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Chapter 47 Tubal Disease
Figure 47-13 Dense adhesions surrounding the tubes and ovaries. Chromopertubation revealed bilateral distal tubal occlusion.
Figure 47-14
Figure 47-16 with sutures.
Salpingostomy is completed by everting the mucosal flap
Figure 47-17
Salpingostomy has been completed.
The tube is grasped with a traumatic forceps.
Table 47-5 Reproductive Outcome after Laparoscopic Salpingostomy Figure 47-15 avascular line.
An opening is made with laparoscopic scissors at the
Prophylactic antibiotics may be all that is necessary to improve implantation rates in the presence of hydrosalpinx, at least in theory. It has been reported in a retrospective study that doxycycline treatment improved the IVF pregnancy rate.63 However, in general, a tubal occlusion procedure is recommended.
Periadnexal Adhesions Reproductive surgery can cause adhesion formation. Most surgery on reproductive organs is not performed for infertility but in women who have a disorder such as a myoma or ovarian cyst and
Author
Number of Patients
Intrauterine Pregnancies
Ectopic Pregnancies
Daniell et al, 198638
48
21%
10%
Canis et al, 199139
87
33%
7%
Dubuisson et al, 199440
90
32%
4%
Sasse et al, 199441
81
23%
14%
Dequesne, 199442
43
10 (20%)
Oh, 199643
82
35%
10%
Kasia et al, 199744
86
11%
6%
Milingos et al, 200045
61
23%
3%
139
32%
17%
Taylor et al, 200146
Only studies with >40 cases were included.
2 (4.6%)
705
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Section 7 Reproductive Surgery want to conceive in the future. Measures such as meticulous handling of the tissue, frequent irrigation with isotonic solution, gentle and minimal tissue handling, and good hemostasis decrease but do not eliminate adhesion formation. Adjunctive therapies, such as prophylactic antibiotics, intraperitoneal corticosteroids, and adhesion-preventing substances also fail to improve the reproductive performance of these women (see Chapter 52). Peritubal and periovarian adhesions impair fertility by interfering with gamete transfer and the ovum pickup mechanism. Removal of these adhesions is associated with improved fecundity. The ASRM (American Fertility Society) classification of adnexal adhesions is shown in Figure 47-18.27 Tulandi and
Table 47-6 Reproductive Outcome after Laparoscopic Fimbrioplasty Number of Patients
Author
Intrauterine Pregnancies
Ectopic Pregnancies
Dubuisson et al, 199047
31
35%
12.9%
Gomel & Erenus, 199048
40
48%
5%
Dequesne, 199442
63
64%
4.7%
Dlugi et al, 199449
113
20.3%
5.3%
Kasia et al, 199744
108
36%
Audebert et al, 199850
35
5.8%
74.3%
22.9%
THE AMERICAN FERTILITY SOCIETY CLASSIFICATION OF ADNEXAL ADHESIONS Patient's Name G
Age
Chart#
Date P
Sp Ab
VTP
Ectopic
Infertile Yes
No
Other Significant History (i.e. surgery, infection,etc.) HSG
Sonography
Photography
Laparoscopy
Laparotomy
TUBE
OVARY
<1/3 Enclosure 1/3 - 2/3 Enclosure > 2/3 Enclosure ADHESIONS R Filmy 1 2 4 4 8 16 Dense 2 4 1 L Filmy 4 8 16 Dense 1 2 4 R Filmy Dense 4* 8* 16 1 2 4 L Filmy 4* 16 Dense 8* * If the fimbriated end of the fallopian tube is completely enclosed, change the point assignment to 16. Prognosis Classification for Adnexal Adhesions LEFT
Additional Findings:
RIGHT
A. Minimal B. Mild C. Moderate D. Severe Treatment (Surgical Procedures):
L
Prognosis for Conception& Subsequent Viable Infant** Excellent (> 75%) Good (50-75%) Fair (25%-50%) Poor (< 25%) **Physician's judgment based upon adnexa with least amount of pathology. Recommended Followup Treatment:
706
Drawing
R
Figure 47-18 American Fertility Society (ASRM) classification of adnexal adhesions.
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Chapter 47 Tubal Disease colleagues evaluated pregnancy occurrence in infertile women with periadnexal adhesions.64 The pregnancy rate in women whose adhesions were lysed by laparotomy was higher than in those untreated. The cumulative probability of conception at 12 and 24 months follow-up were 8% and 13%, respectively, in the nontreated group and 40% and 42%, respectively, in the treated group. The ectopic pregnancy rate between the treated and nontreated group was similar. Intrinsic damage to the fallopian tube is more important in the development of ectopic pregnancy than the adhesions. Lysis of adhesions can be performed using laparoscopic scissors, electrocautery, or laser. The results are similar.65–68 The vascular type of adhesions should be coagulated first or vaporized with the laser. The procedure is performed by keeping the adhesions under tension with grasping forceps and divided. Filmy adhesions are divided, but dense adhesions should be excised. The overall pregnancy rate after laparoscopic salpingo-ovariolysis is 60% and the ectopic pregnancy rate is 5%.65 However, the pregnancy rate after salpingo-ovariolysis in women with severe and dense adhesions is poor (10% to 15%). These patients are better treated with IVF. In a retrospective study, there was no statistical difference between the cumulative conception rates of microsurgical and laparoscopic adhesiolysis after being stratified according to the duration of infertility.66 In addition, there was no difference in adhesion score after microsurgical and laparoscopic adhesiolysis. However, the laparoscopic approach has additional benefits, such as reduced postoperative pain, fast recovery, short hospital stay, and reduced risk of infection and thromboembolic accidents. The benefit of second-look laparoscopy was studied by Tulandi and coworkers in a randomized, prospective study.68 There was no increase in the pregnancy rate or decrease in the incidence of ectopic pregnancy after a second-look laparoscopy done 1 year after reproductive surgery.
However, it is often associated with false proximal occlusion, which could be due to tubal spasm or mucosal debris. As a result, nonvisualized tube is not synonymous with true occlusion, and it should be followed by selective tubal catheterization. If catheterization fails, patients are better treated with IVF. The most common cause of midtubal occlusion is iatrogenic after tubal sterilization. Reversal of tubal sterilization by reanastomosis is the most successful tubal reconstructive surgery. Also unlike IVF, several pregnancies could be achieved. Alternatively, patients, especially older women, can be offered assisted reproductive technology. In general, women with hydrosalpinx will have a better chance to conceive with IVF if the tube is removed. Hydrosalpinx fluid impairs implantation. Young women with tubal infertility who wish to conceive spontaneously can be offered reconstructive tubal surgery; this should be done by laparoscopy. Older premenopausal women and those with severe tubal damage should be offered IVF.
PEARLS Tubal disease remains one of the most common causes of infertility. HSG remains the best approach to evaluation of tubal disease. Proximal tubal occlusion is commonly found on HSG and may resolve spontaneously. Therefore a repeat HSG is recommended before attempt at correction. The best method for correction of proximal tubal occlusion is by fluoroscopic or hysteroscopic cannulation. Midtubal occlusion is typically caused by a previous tubal ligation and is amenable to reversal by laparoscopic technique. Distal tubal occlusion that is severe should be treated by IVF. However, less severe forms can be treated with surgery. Ectopic pregnancy is increased after tubal surgery. Hydrosalpinx that is severe, especially if visible on ultrasonography, should be removed before IVF.
●
● ●
●
●
●
● ●
CONCLUSIONS HSG remains the most widely used technique to evaluate tubal patency. It is simple, economical, and might lead to conception.
REFERENCES 1. Westrom L: Incidence, prevalence, and trends of acute pelvic inflammatory disease and its consequences in industrialized countries. Am J Obstet Gynecol 138:880–892, 1980. 2. DeCherney AH, Cholst I, Naftolin F: Structure and function of the fallopian tubes following exposure to diethylstilbestrol (DES) during gestation. Fertil Steril 36:741–745, 1981. 3. Novy M, Thurmond AS, Patton P, et al: Diagnosis of cornual obstruction by transcervical fallopian tube cannulation. Fertil Steril 50:434–440, 1988. 4. Hurd WW, Wyckoff ET, Reynolds DB, et al: Patient rotation and resolution of unilateral cornual obstruction during hysterosalpingography. Obstet Gynecol 101:1275–1278, 2003. 5. Steiner AZ, Meyer WR, Clark RL, Hartmann KE: Oil- Soluble contrast during hysterosalpingography in women with proven tubal patency. Obstet Gynecol 101:109–113, 2003. 6. Ekerhoved E, Fried G, Granberg S: An ultrasound-based approach to the assessment of infertility, including the evaluation of tubal patency. Best Pract Res Clin Obstet Gynecol 18:13–28, 2004. 7. Holz K, Becker R, Schurmann R: Ultrasound in the investigation of tubal patency. A meta-analysis of three comparative studies of Echovist-
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200 including 1007 women. Zentralblatt fur Gynekologie 119:366–373, 1997. Gordts S, Watrelot R, Campo R, Brosens I: Risk and outcome of bowel injury during transvaginal pelvic endoscopy. Fertil Steril 76:1238–1241, 2001. Brosens IA, Boeckx W, Delattin P, et al: Salpingoscopy: A new preoperative diagnostic tool in tubal surgery. BJOG 94:768–773, 1987. Marana R, Catalano GF, Muzii L, et al: The prognostic role of salpingoscopy in laparoscopic tubal surgery. Hum Reprod 14:2991–2995, 1999. Marchino GL, Gigante V, Gennarelli G, et al: Salpingoscopic and laparoscopic investigation in relation to fertility outcome. J Am Assoc Gynecol Laparosc 8:218–221, 2001. Gordts S, Campo R, Puttemans P, et al: A one-step outpatient endoscopy based approach. Hum Reprod 17:1684–1687, 2002. Kerin J, Daykhosky L, Segalowitz J, et al: A microendoscopic technique for visual exploration of the human fallopian tube from the uterotubal ostium to the fimbriae using a transvaginal approach. Fertil Steril 54:390–400, 1990.
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14. Surrey ES, Adamson GD, Surrey MW, et al: Introduction of new coaxial falloposcopy system: A multicenter feasibility study. J Am Assoc Gynecol Laparosc 4:473–478, 1997. 15. Pearlstone AC, Surrey ES, Kerin F: The linear everting catheter: A nonhysteroscopic transvaginal technique for access and microendoscopy of the fallopian tube. Fertil Steril 58:854–857, 1992. 16. Malik S: Genital tuberculosis and implantation in assisted reproduction. Rev Gynecol Pract 3:160–164, 2003. 17. Sulak PJ, Letterie GS, Coddington CC, et al: Histology of proximal tubal occlusion. Fertil Steril 48:437–440, 1987. 18. Ransom M, Garcia A: Surgical management of cornual–isthmic tubal obstruction. Fertil Steril 68:887–891, 1997. 19. Gillette WR, Herbison GP: Tubocornual anastomosis: Surgical considerations and coexistent infertility factors in determining the prognosis. Fertil Steril 51:241–246, 1989. 20. Donnez J, Casanas-Roux F, Nisolle-Pochet M, et al: Surgical management of tubal obstruction at the uterotubal junction. Acta Eur Fertil 18:5–9, 1987. 21. Lavy G, Diamond MP, DeCherney AH: Pregnancy following tubocornual anastomosis. Fertil Steril 46:21–25, 1986. 22. Gomel V: An odyssey through the oviduct. Fertil Steril 39:144–156, 1983. 23. Diamond E: A comparison of gross and microsurgical techniques for the repair of cornual occlusion in infertility: A retrospective study, 1968–1978. Fertil Steril 32:370–376, 1979. 24. Grant A: Infertility surgery of the oviduct. Fertil Steril 22:496–503, 1971. 25. Honere GM, Holden AE, Schenken RS: Pathophysiology and management of proximal tubal blockage. Fertil Steril 71:785–795, 1999. 26. Platz-Christensen JJ, Tronstad SE, Johansson O, Carlsson SA: Evaluation of regret after tubal sterilization. Int J Gynaecol Obstet 38:223–226, 1992. 27. American Fertility Society: Classification of adnexal adhesions, distal tubal occlusion, tubal occlusion secondary to tubal ligation, tubal pregnancies, müllerian anomalies and intrauterine adhesions. Fertil Steril 49:944–955, 1988. 28. Yoon TK, Sung HR, Kang HG, et al: Laparoscopic tubal anastomosis: Fertility outcome in 202 cases. Fertil Steril 72:1121–1126, 1999. 29. Hawkins J, Dube D, Kaplow M, Tulandi T: Cost analysis of tubal anastomosis by laparoscopy and by laparotomy. J Am Assoc Gynecol Laparosc 9:120–124, 2002. 30. DeCherney AH, Mezer HC, Naftolin F: Analysis of failure of microsurgical anastomosis after mid-segment, non-coagulation tubal ligation. Fertil Steril 39:618–622, 1983. 31. Paterson PJ: Factors influencing the success of microsurgical tuboplasty for sterilization reversal. Clin Reprod Fertil 3:57–64, 1985. 32. Lu ZY: Tubal anastomosis for reversal of sterilization with microsurgical technique in 246 women. Zhonghua Fu Chan Ke Za Zhi 24:203–205, 1989. 33. Kim SH, Shin CJ, Kim JC, et al: Microsurgical reversal of tubal sterilization: A report on 1118 cases. Fertil Steril 68:865–870, 1997. 34. Bisonette F, Lapensee L, Bouzayen R: Outpatient laparoscopic tubal anastomosis and subsequent fertility. Fertil Steril 72:549, 1999. 35. Dubuisson JB, Chapron CL: Single suture laparoscopic tubal reanastomosis. Curr Opin Obstet Gynecol 10:307–313, 1998. 36. Falcone T, Goldberg JM, Margossian H, Stevens L: Robotically assisted laparoscopic microsurgical tubal anastomosis: A human pilot study. Fertil Steril 73:1040–1042, 2000. 37. Watson A, Vandekerckhove P, Lilford R: Techniques for pelvic surgery in subfertility. Cochrane Database Syst Rev 2003; 3:CD000221. 38. Daniell JF, Diamond MP, McLaughlin DS, et al: Clinical results of terminal salpingostomy with the use of the CO2 laser: Report of the intra-abdominal laser study group. Fertil Steril 45:175–178, 1986. 39. Canis M, Mage G, Pouly JL, et al: Laparoscopic distal tuboplasty: Report of 87 cases and a four years experience. Fertil Steril 56: 616–621, 1991. 40. Dubuisson JP, Chapron C, Morice P, et al: Laparoscopic salpingostomy: Fertility results according to the tubal mucosal appearance. Hum Reprod 9:334– 339, 1994.
41. Sasse V, Karageorgieva E, Keckstein J: Laparoscopic treatment of distal tubal occlusion-reocclusion and pregnancy rate. J Am Assoc Gynecol Laparosc 1:S32, 1994. 42. Dequesne JG: CO2 laser laparoscopy in tubo-ovarian infertility. J Am Assoc Gynecol Laparosc 1:S10, 1994. 43. Oh ST: Tubal patency and conception rates with three methods of laparoscopic terminal salpingostomy. J Am Assoc Gynecol Laparosc 3:519–523, 1996. 44. Kasia J, Raiga J, Doh A, et al: Laparoscopic fimbrioplasty and neosalpingostomy: Experience of the Yaounde General Hospital, Cameroon (report of 194 cases). Eur J Obstet Gynecol Reprod Biol 73:71–77, 1997. 45. Milingos SD, Kallipolitis GK, Loutradis DC, et al: Laparoscopic treatment of hydrosalpinx: Factors affecting pregnancy rate. J Am Assoc Gynecol Laparosc 7:355–361, 2000. 46. Taylor RC, Berkowitz J, McComb PF: Role of laparoscopic salpingostomy in the treatment of hydrosalpinx. Fertil Steril 75:594–600, 2001. 47. Dubuisson PJ, Bouquet De Joliniere J, Aubriot FX, et al: Terminal tuboplasties by laparoscopy: 65 consecutive cases. Fertil Steril 54:401–403, 1990. 48. Gomel V, Erenus M: Prognostic value of the American Fertility Society’s (AFS) classification for distal tubal occlusion (DTO). In American Fertility Society 46th Annual Meeting program Supplement (p097). Washington, D.C., American Fertility Society, 1990, p S106. 49. Dlugi AM, Reddy S, Saleh WA, et al: Pregnancy rates after operative endoscopic treatment of total (neosalpingostomy) or near total (salpingostomy) distal tubal occlusion. Fertil Steril 62:913–920, 1994. 50. Audebert A, Pouly JL, Von Theobald P: Laparoscopic fimbrioplasty: An evaluation of 35 cases. Hum Reprod 13:1496–1499, 1998. 51. Anderson AN, Yue Z, Meng FJ, Petersen K: Low implantation rate after in vitro fertilization in patients with hydrosalpinges diagnosed by ultrasonography. Hum Reprod 9:1935–1938, 1994. 52. Strandell A, Waldenstrom NL, Hamberger L: Hydrosalpinx reduces in vitro fertilization/embryo transfer pregnancy rates. Hum Reprod 9:861–863, 1994. 53. Vandromme J, Chasse E, Lejeune B, et al: Hydrosalpinges in in vitro fertilization: An unfavorable feature. Hum Reprod 10:576–579, 1995. 54. Bedaiwy MA, Goldberg JM, Falcone T, et al: Relationship between oxidative stress and embryotoxicity of hydrosalpingeal fluid. Hum Reprod 17:601–604, 2002. 55. Bedaiwy MA, Falcone T, Goldberg JM, et al: The relationship between cytokines and the embryotoxicity of hydrosalpingeal fluid. J IVF Genet 22:171–176, 2005. 56. Blazar AS, Hogan JW, Seifer DB, et al: The impact of hydrosalpinx on successful pregnancy in tubal factor infertility treated by in vitro fertilization. Fertil Steril 67:517–520, 1997. 57. Camus E, Poncelet C, Goffinet F, et al: Pregnancy rates after in vitro fertilization in cases of tubal infertility with and without hydrosalpinx: A meta-analysis of published comparative studies. Hum Reprod 14:1243–1249, 1999. 58. Zeyneloglu HB, Arici A, Olive D: Adverse affects of hydrosalpinx on pregnancy rates after in vitro fertilization–embryo transfer. Fertil Steril 11:208–2084, 1998. 59. Strandell A, Lindhard A, Waldenstrom U, Thorburn J: Hydrosalpinx and IVF outcome: Cumulative results after salpingectomy in a randomized controlled trial. Hum Reprod 16:2403–2410, 2001. 60. Sagoskin AW, Lessey BA, Mottla GL, et al: Salpingectomy or proximal tubal occlusion of unilateral hydrosalpinx increases the potential for spontaneous pregnancy. Hum Reprod 18:2634–2637, 2003. 61. Surrey ES, Schoolcraft WB: Laparoscopic management of hydrosalpinges before in vitro fertilization–embryo transfer: Salpingectomy versus proximal tubal occlusion. Fertil Steril 75:612–617, 2001. 62. Johnson N, Mak W, Sowter M: Laparoscopic salpingectomy for women with hydrosalpinges enhances the success of IVF: A Cochrane review. Hum Reprod 17:543–548, 2002. 63. Hurst BS, Tucker KE, Awoniyi CA, Schlaff WD: Hydrosalpinx treated with extended doxycycline does not compromise the success of in vitro fertilization. Fertil Steril 75:1017–1019, 2001.
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Chapter 47 Tubal Disease 64. Tulandi T, Collins JA, Burrows E: Treatment-dependent and treatmentindependent pregnancy among women with periadenexal adhesions. Am J Obstet Gynecol 162:354–357, 1990. 65. Tulandi T, Bugnah M: Operative laparoscopy: Surgical modalities. Fertil Steril 63:237–245, 1995. 66. Saravelos HG, Li TC, Cooke ID: An analysis of the outcome of microsurgical and laparoscopic adhesiolysis for infertility. Hum Reprod 10:2887–2894, 1995.
67. Tulandi T: Salpingo-ovariolysis: A comparison between laser surgery and electrosurgery. Fertil Steril 45:489–491, 1986. 68. Tulandi T, Falcone T, Kafka I: Second-look operative laparoscopy one year following reproductive surgery. Fertil Steril 52:421–424, 1989.
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48
Ectopic Pregnancy Beata Seeber and Kurt Barnhart
INTRODUCTION Ectopic pregnancy, the implantation of a fertilized ovum outside the endometrial cavity, is a curious phenomenon unique to primates. It does not occur in laboratory animals and has likewise not been reported in domestic or farm animals. In addition, no animal model of the disease exists. If undiagnosed or untreated, ectopic pregnancy may result in rupture of the fallopian tube and massive intraperitoneal hemorrhage. In the past decade, this phenomenon accounted for approximately 9% of maternal pregnancy-related deaths in the United States.1 Because ectopic pregnancy diagnosis and treatment has moved from an inpatient to an outpatient setting, there are no clear reporting standards, and the most up-to-date incidence rates and morbidity and mortality statistics date back to the mid-1990s.1 Fortunately, due to increased awareness of this problem by clinicians and the public, coupled with improved methods of diagnosis and treatment, the outcomes for women with ectopic pregnancy appear to be improving. Today, complications of ectopic pregnancy stem from misdiagnosis or delay in seeking medical care. It is no longer the case that the disease entity is missed due to a deficit in clinical knowledge or lack of means to diagnosis. Despite this, however, the condition continues to be a major cause of morbidity and mortality in reproductive-age women. This chapter reviews the epidemiology and pathophysiology of ectopic pregnancy, the clinical presentation and diagnosis of the disease, surgical and medical treatments, and reproductive outcomes.
EPIDEMIOLOGY It is estimated that about 2% of pregnancies in the United States are ectopic pregnancies. The number of ectopic pregnancies diagnosed in the United States continues to rise, with a sixfold increase documented between 1970 and 1992.2–4 In Europe, the prevalence of ectopic pregnancy appears stable in France, Sweden, and the Netherlands, but has continued to increase in Norway.4 U.S. healthcare statistics demonstrate that of the 108,800 patients diagnosed with ectopic pregnancy in 1992, 58,000 needed hospitalization, at a cost of $1.1 billion.5 Recent trends of outpatient treatment and decreased need for hospitalization have likely led to an underreporting of the condition and a consequent underestimation in U.S. government figures. The etiology of the observed increase in ectopic pregnancy prevalence appears to be multifaceted. An important factor
appears to be the recent rise in sexually transmitted diseases, leading to an increased incidence of clinical and subclinical tubal infections. Another contributing factor may be our improved ability to diagnose ectopic pregnancies earlier and more accurately. Finally, the increased utilization of assisted reproductive technologies is believed to play a role in this increased prevalence. The vast majority of ectopic pregnancies (more than 90%) occur in the tube, with 80% to 90% of these occurring in the ampullary region, 5% to 10% in the isthmic region, 5% in the fimbrial region, and about 2.4% located in the cornual (interstitial) region. The other sites include 3.2% in the ovary, 1.3% elsewhere in the abdomen, and less than 0.15% in the cervix.6–8
Etiology Ectopic pregnancies are believed to occur primarily as a result of factors that delay or prevent the passage of the fertilized egg into the uterine cavity. Partial or complete blockage of a fallopian tube may arrest the passing embryo in the fallopian tube lumen. Even if the tube is still patent, inflammation and infection may damage the endosalpinx of the tube. Resultant abnormalities in ciliary function are believed to impede transport of the embryo through the fallopian tube.9 The most common cause of such tubal damage is believed to be clinical or subclinical infections caused by Chlamydia trachomatis or Neisseria gonorrhoeae. It is hypothesized that in some cases embryo factors (including cytogenetic abnormalities) may lead to premature implantation in a nonendometrial site. However, recent studies that have examined the role of chromosome abnormalities in ectopic pregnancy have not supported earlier case reports of high proportions of genetically abnormal gestations at ectopic sites. Among 22 surgically excised tubal pregnancies, only one abnormal chromosomal complement was found.10 In a larger review of 62 karyotyped ectopic pregnancies, 4.8% showed chromosomal abnormalities, a figure which matched that expected for maternal and gestational age of the cases.11
Risk Factors Multiple risk factors have been consistently shown to be associated with ectopic pregnancies (Table 48-1).12 The strongest association has been found with prior pelvic inflammatory disease (PID), a prior history of ectopic pregnancy, and previous tubal surgery (including previous tubal ligation). These conditions are believed to alter tubal integrity and thus impede the migration of the fertilized ovum to the uterus. Weaker associations have been made between ectopic pregnancy and infertility (a possible marker in some patients for
711
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Section 7 Reproductive Surgery Table 48-1 Risk Factors for Ectopic Pregnancy Strong Associations Tubal surgery Pelvic inflammatory disease Prior ectopic pregnancy Weaker Associations Infertility Cigarette smoking Increasing age More than one lifetime sexual partner Abdominal or pelvic surgery Sexually transmitted diseases (gonorrhea and/or chlamydia) Intrauterine device use No Clear Association Oral contraceptive use Prior spontaneous miscarriage Prior elective termination of pregnancy Cesarean section
subclinical tubal infection), cigarette smoking (thought to affect tubal motility), increasing age, having more than one lifetime sexual partner, any pelvic or abdominal surgery (other than cesarean delivery), and a history of having a sexually transmitted disease. Although use of an intrauterine device (IUD) does not increase the risk of ectopic pregnancy compared to controls, women using an IUD found to have a positive pregnancy test are more likely to have an ectopic than an intrauterine pregnancy, in a manner similar to women who have had a tubal ligation.13 Unfortunately, the sensitivity of these risk factors is low, and as many as 50% of patients with proven ectopic pregnancies will have none.13 No clear association has been documented between ectopic pregnancy and oral contraceptive use, previous elective pregnancy termination or spontaneous miscarriage, or cesarean section.9,10 Improved Diagnosis
Diagnostic accuracy has improved as a result of more sensitive pregnancy tests and pelvic ultrasound. The advent of radioimmunoassay and specific antiserum to the beta-subunit of human chorionic gonadotropin (hCG) has allowed for the accurate quantification of β-hCG and the ability to closely follow its rise and fall.14 High-resolution transvaginal ultrasonography with Doppler flow imaging has led to improved visualization of adnexal masses, including ectopic pregnancies, at earlier gestational ages. Assisted Reproductive Technologies
Assisted reproductive technologies (ART) appear to increase the risk of ectopic pregnancies as a result of both preexisting pathology and effects inherent to these techniques. Not only do many subfertile women have tubal abnormalities, but ovulation induction also results in hormonal fluctuations that are hypothesized to alter tubal motility in some women. After oocyte retrieval, in vitro fertilization (IVF), and embryo transfer, the incidence of tubal pregnancy can be as high as 4.5%.15 Heterotopic Pregnancy
712
IVF also appears to increase the incidence of simultaneous intrauterine and ectopic pregnancy, termed heterotopic pregnancy.16 In the late 1940s, the prevalence of heterotopic pregnancy
was estimated to be 1:30,000 pregnancies.17 The prevalence is now estimated to be 1:4000 pregnancies in the general population, and as high as 1:100 pregnancies resulting from IVF.15,18,19 This dramatic increase is believed to be the result of the increased risk of multiple pregnancies and the unknown effects on tubal motility, in combination with the invasive nature of ART. The clinician must be aware that although ultrasound verification of intrauterine pregnancy dramatically decreases the chance of an ectopic pregnancy, it does not completely rule it out, especially in patients whose pregnancy has resulted from ART.
Ruptured Ectopic Pregnancy Fallopian tube rupture secondary to ectopic pregnancy remains relatively common despite greater awareness of the disease and improved diagnostic modalities. This is because there is little or no correlation between tubal rupture time since last menstrual period, physical findings, symptoms or β-hCG level. In a large retrospective study of 700 women with ectopic pregnancies, the rupture rate was 34% and one third of patients had no symptoms prior to rupture.20 The primary risk factors for tubal rupture in this study were no prior history of ectopic pregnancy and multiparity. Likewise, there is little relationship between the onset of ectopic pregnancy symptoms and subsequent tubal rupture. In one study with an overall rupture rate of 32%, less than one fourth of the ruptures occurred within the first 48 hours of symptom onset.21 The remaining ruptures occurred at a fairly steady rate of 2.5% per 24 hours of untreated symptoms for the next 2 weeks. It is surprising that there is no correlation between tubal rupture and β-hCG levels. In one study, 11% of patients with ruptured ectopic pregnancies had β-hCG levels less than 100 IU/L.16 Even declining β-hCG levels are not clinically reassuring, because fallopian tube rupture can occur when serial β-hCG measurements demonstrate a dropping level, as well as when the β-hCG level is very low.22,23
PRESENTATION Symptoms The most common symptoms of ectopic pregnancy are abdominal or pelvic pain and vaginal bleeding or spotting in a patient with a positive pregnancy test. However, both the sensitivity and specificity of these symptoms for ectopic pregnancy are low. In some cases, these symptoms can be intermittent or even absent. Depending on their degree, these can sometimes be mistaken for a normal menstrual period or early pregnancy loss; thus some women may not initially report them to their physicians. Even though these symptoms may be due to other conditions, pain and bleeding during early pregnancy are always an indication to exclude ectopic pregnancy. Pain
Pain associated with an ectopic pregnancy can range from mild to severe and can be unilateral or bilateral. The pain is believed to be related to tubal distension from the proliferating chorionic villi and hemorrhage into the tubal lumen, as well as peritoneal irritation secondary to leakage of blood into the peritoneal cavity.
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Chapter 48 Ectopic Pregnancy Vaginal Bleeding
Vaginal bleeding occurs in more than 50% of ectopic pregnancies and can range from scant spotting to heavy bleeding. It is hypothesized that vaginal bleeding occurs because the thickened endometrial lining is not well supported by the abnormal hormonal milieu. Theoretically, lower β-hCG production associated with most ectopic pregnancies stimulates the corpus luteum to produce an inadequate amount of progesterone. Some patients may even report passing tissue vaginally. In such cases, it is important to keep in mind that a “decidual cast” from the endometrial cavity can easily be mistaken for tissue, and only microscopically confirmed chorionic villi should be used to confirm that the pregnancy was intrauterine.17
Physical Examination Findings on physical examination can vary dramatically and do not always correlate with the size of the ectopic pregnancy or whether or not it is ruptured. Patients with unruptured ectopic pregnancies usually have normal vital signs, although pain-related tachycardia is not uncommon. Lower abdominal tenderness on the affected side is common, but it may be found on the contralateral side as well, sometimes as a result of a corpus luteum cyst on that side. The clinician must keep in mind that a normal physical examination does not exclude an ectopic pregnancy. Pelvic Examination
On pelvic examination, inspection of the cervix will usually reveal a closed os, with or without bleeding. A vigorous bimanual examination in search of an adnexal mass is contraindicated if an ectopic pregnancy is suspected. In the presence of adnexal tenderness, the size and characterization of any adnexal masses is best determined by ultrasound. Bimanual pressure on a fragile ectopic pregnancy can result in rupture, converting a stable patient into a surgical emergency. Even when an ectopic pregnancy is present, an adnexal mass will be palpable in more than 10% of cases, and in one third of these cases, the mass will ultimately prove to be unrelated to the ectopic pregancy (e.g., a corpus luteum cyst).17
Ruptured Tubal Pregnancy Tubal rupture is often, but not always, associated with signs of peritoneal irritation, such as rebound tenderness and guarding. Hypotension and tachycardia are indications for immediate fluid resuscitation and expedient surgical intervention. Presumed hemoperitoneum can be confirmed by bedside transabdominal ultrasound, if it will not delay surgery.
DIAGNOSIS Early in pregnancy, it is often impossible to differentiate a viable pregnancy from an impending spontaneous abortion or an ectopic pregnancy. The diagnosis of an ectopic pregnancy is therefore a diagnosis of exclusion, utilizing modern noninvasive diagnostic approaches.
Ultrasonography The first step in evaluating a pregnancy is to determine viability. If the pregnancy is determined to be nonviable, the second step
is to differentiate between an abnormal intrauterine pregnancy (spontaneous abortion) and an ectopic pregnancy. Therefore, the first step in a diagnostic workup for ectopic pregnancy is to verify or exclude an intrauterine pregnancy (normal as well as abnormal), because the odds of heterotopic pregnancies are extremely low even after IVF. Intrauterine Pregnancy Confirmation
The confirmation of an intrauterine pregnancy requires the identification of a series of structures by vaginal ultrasound, including the gestational sac, yolk sac, and fetal pole with or without cardiac motion. The gestational sac is seen first and appears as a thick, echogenic rim surrounding a sonolucent center in an eccentric location of the endometrial stripe. This is often referred to as the double decidual sign. The yolk sac is a bright echogenic rim with a sonolucent center that can be seen by approximately 5 weeks’ gestational age. The fetal pole develops as a thickening along an edge of the yolk sac, with cardiac motion first seen around 51⁄2 to 6 weeks after the last menstrual period, even in the case of multiple gestations. The diagnostic accuracy of transvaginal ultrasound for identifying an intrauterine pregnancy approaches 100% in gestations greater than 51⁄2 weeks.24 A pseudosac may sometimes be mistaken for a gestational sac. This is a collection of fluid within the endometrial cavity that occurs due to bleeding from the decidualized endometrium when an extrauterine gestation is present. A pseudosac can usually be distinguished from a real gestational sac by its central location, filling the endometrial cavity itself. Adnexal Findings
Ectopic pregnancies can often be seen in the adnexa with vaginal ultrasound. The most common finding is an inhomogeneous mass, which has been reported to be visible in approximately half of patients with ectopic pregnancies in some series.25 Less commonly, a mass with a hyperechoic ring around the gestational sac can be seen. The ability to visualize an ectopic pregnancy is ultimately dependent on the quality of the ultrasound equipment and the experience of the sonographer. Even in the best of circumstances, no evidence of pregnancy either in the uterus or the adnexa is a common finding in patients subsequently proven to have an ectopic pregnancy.
Human Chorionic Gonadotropin Quantitative measurement of serum β-hCG is a very accurate method for determining gestational age in the first trimester of a normal pregnancy.26 This is extremely important in the diagnosis of ectopic pregnancy, because at the time of initial evaluation, many women will be unsure of their menstrual or conception dates; thus the exact gestational age is not known. The use of radioimmunoassay to measure serum β-hCG has greatly improved the time to obtain results as well as their accuracy. Discriminatory Zone
An important factor when determining the viability and location of a pregnancy by vaginal ultrasound is the discriminatory zone. The discriminatory zone is defined as that level of β-hCG at which a normal singleton intrauterine pregnancy can be visualized
713
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Section 7 Reproductive Surgery on transvaginal ultrasonography.28 At most institutions, the discriminatory zone for a singleton pregnancy when using transvaginal ultrasonography is between 1500 and 2500 mIU/mL (using the WHO Third International Standard, or International Reference Preparation).2 Each clinician will have to determine the discriminatory zone in their practice. Important variables include the type of β-hCG test used, the expertise of the ultrasonographer, and the quality of the ultrasound equipment. If the discriminatory zone is set too high, diagnosis of ectopic pregnancies will be delayed. If the discriminatory zone is set too low, the risk of intervening in a normal intrauterine pregnancy increases. This is especially important in patients who have become pregnant after ART, because multiple gestations can present with a β-hCG level well above the discriminatory zone long before an intrauterine pregnancy is visible by vaginal ultrasound. In practice, the discriminatory zone should be used as a guide rather than an absolute. In a symptomatic patient whose β-hCG is above the discriminatory zone but has no evidence of an intrauterine pregnancy, intervention is often warranted. In contrast, in an asymptomatic patient with this same scenario, repeat measurements will often demonstrate viability of normal, and sometimes multiple, gestations. Like all gray areas of medical diagnosis, patient education should be aimed at minimizing both anxiety and risk to the patient while waiting to make a definitive diagnosis. Serial -hCG Determination
To distinguish a normal intrauterine pregnancy from a nonviable intrauterine or ectopic gestation, serial β-hCG determinations are performed. It is now well-established that the beta-hCG concentration rises almost linearly in the early weeks of a normally growing gestation, doubling every 1.4 to 2.1 days.27–29 Many clinicians rely on the rule of at least a 66% rise in β-hCG over 2 days based on earlier studies.27,30–33 More recent evidence suggests that the rise of β-hCG may be slower than previously reported, with 99% of all normal viable intrauterine pregnancies having an increase in β-hCG of at least 24% in 1 day and 53% in 2 days.34 Intervening when the 2-day rise in β-hCG is between 53% and 66% may result in the interruption of a viable pregnancy.
Uterine Cavity Sampling
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If the β-hCG level is not rising normally and is above the discriminatory zone, and an intrauterine pregnancy is not visualized by ultrasound, the diagnosis of an abnormal, nonviable gestation can be made with relative certainty. To differentiate between a spontaneous miscarriage and an ectopic pregnancy, the uterine cavity should be sampled to determine the presence or absence of chorionic villi. This is most commonly done by performing a dilation and curettage (D&C) in the operating room. Failure to accurately detect the presence of chorionic villi can lead to unnecessary surgical and medical interventions in women without an ectopic pregnancy. In cases where gross products of conception (gestational sac or fetal parts) are not visible, verification of the presence of chorionic villi can be a problem, because final diagnosis with a permanent pathologic specimen takes up to 24 hours. One solution is to obtain a frozen section at the time of D&C, which
has been shown to be very accurate in identifying products of conception, with almost no risk of false-positive results.35 Other techniques used to identify chorionic villi have not been found to be as sensitive. Floating the tissue obtained in saline solution will allow the trained gynecologist to identify villi in only 60% of cases where they can be identified histologically.36 The use of a stereomicroscope significantly improves the ability to identify chorionic villi, but is rarely available in common practice.37 Sampling of the uterine cavity with a pipelle biopsy instrument in an outpatient setting has been found to have relatively poor sensitivity of 30% to 63%.38,39 In the future, perhaps other forms of less invasive endometrial sampling, such as the handheld manual vacuum aspirator, will prove to have the necessary sensitivity for confirming products of conception.
Other Diagnostic Tests Other techniques have been used to diagnose ectopic pregnancy. Prior to accurate ultrasound, culdocentesis was used to diagnose acute intra-abdominal bleeding. For this often painful transvaginal technique, a spinal needle is placed though the posterior cul-de-sac to aspirate peritoneal fluid. The presence of clotting blood indicates hemoperitoneum secondary to acute bleeding, because blood that had been present for any period of time will have already lysed, and thus not clot. Today, the presumptive diagnosis of hemoperitoneum is made by transvaginal ultrasound whenever a hemodynamically compromised patient with a positive pregnancy test is found to have free intra-abdominal fluid. Serum progesterone levels have also been used to aid in the diagnosis of ectopic pregnancy. Overall, serum progesterone levels are lower in ectopic pregnancies than in intrauterine pregnancies.40 Levels less than 5 ng/mL are almost always (99.8%) associated with nonviable pregnancies, but these can be either abnormal intrauterine pregnancies (impending spontaneous abortion) or ectopic pregnancies.41 Conversely, progesterone levels of greater than 17.5 ng/mL are rarely associated with ectopic pregnancies, with only 8% of ectopic pregnancies falling into this category. Despite these strong correlations at either end of the concentration spectrum, serum progesterone levels have limited value in diagnosing ectopic pregnancies, because many patients’ values will fall between these extremes of values, where there is too much overlap to be discriminatory.42 In addition, serum progesterone levels are not readily available in many hospital laboratories on a “stat” basis, making the use of this test impractical in emergency situations. Other laboratory tests evaluated for usefulness in the diagnosis of ectopic pregnancy include vascular endothelial growth factor (VEGF), CA-125, fetal fibronectin, and creatine kinase.43–49 Like serum progesterone, overlapping ranges of values for normal and abnormal pregnancies have prevented any of these markers from being useful in distinguishing ectopic and nonectopic gestations. Using genomics approaches, other promising serum protein markers have been identified that may ultimately prove to be discriminatory between intrauterine and ectopic pregnancies.50
Algorithm for Diagnosis A simple diagnostic algorithm using ultrasound and serum β-hCG determinations can be helpful (Fig. 48-1).51 When a
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Chapter 48 Ectopic Pregnancy Figure 48-1 Diagnostic algorithm flow chart (adapted from Gracia CR, Barnhart KT: Diagnosing ectopic pregnancy: A decision analysis comparing six strategies. Obstet Gynecol 97:464-470, 2001.)
Early pregnancy with pain and bleeding
Ultrasound
IUP
Abnormal IUP
Nondiagnostic
Ectopic pregnancy
Expectant management
D&C vs. medical management with misoprostol
β-hCG
Treat EP
> Discriminatory
< Discriminatory
zone (no IUP)
zone
D&C
No chorionic villi
Treat EP (MTX vs. surgery)
Abnormal rise or fall
Chorionic villi
Serial β-hCG
Normal fall
Normal rise
No treatment
Ultrasound when β-hCG > discriminatory zone (back to top)
patient presents in early pregnancy with pain or uterine bleeding, the first step is transvaginal ultrasound. If a nonviable intrauterine pregnancy (e.g., impending spontaneous abortion) is visualized, standard management options are indicated based on symptomatology. Likewise, if an ectopic pregnancy is seen in the adnexa, treatment options are clear. If the ultrasound is nondiagnostic, revealing neither an intrauterine or ectopic pregnancy, and the β-hCG is below the discriminatory zone, the most likely diagnosis remains an intrauterine pregnancy, and viability needs to be determined. To distinguish between a growing intrauterine pregnancy and a nonviable gestation, serial β-hCG determinations are performed. As long as serial β-hCG levels rise appropriately, treatment remains expectant. If serial β-hCG levels rise at an abnormal rate, plateau, or drop, a nonviable pregnancy is diagnosed and a D&C is needed to differentiate between an abnormal intrauterine pregnancy and an ectopic pregnancy. Likewise, when vaginal ultrasound is nondiagnostic and the initial or subsequent β-hCG level is found to be well above the discriminatory zone, the next step for diagnosis and treatment of the symptomatic patient is D&C. Caution should be used in the asymptomatic patient with a β-hCG level at or slightly above the discriminatory zone, because viable multiple gestations can have β-hCG levels above the discriminatory zone before the time that an intrauterine pregnancy can be seen with vaginal ultrasound.
Identification of chorionic villi in the D&C specimen verifies the diagnosis of spontaneous abortion, and further treatment is rarely needed. Alternatively, inability to identify chorionic villi makes an ectopic pregnancy the most likely diagnosis. At this point, a decision must be made between either surgical or medical treatment. In some cases where no chorionic villi are found on D&C, the clinical history is suggestive of a complete spontaneous abortion before evacuation, with heavy vaginal bleeding with passage of tissue and an open cervix. In these cases, it is appropriate to manage the patient expectantly with re-evaluation of serum β-hCG levels 12 to 24 hours after evacuation. If the β-hCG level drops sharply from preoperative levels, a complete spontaneous abortion is the most likely diagnosis, although a resolving ectopic pregnancy (sometimes referred to as a tubal abortion) is also possible. Keep in mind that 35% of women with an ectopic pregnancy are diagnosed when the β-hCG level is falling.28 If the β-hCG level plateaus or continues to rise, an ectopic pregnancy is highly likely, and immediate treatment should be instituted. This approach can also be used when the clinical suspicion of ectopic pregnancy is low, but no pathologist is available for intraoperative examination of the D&C specimen. All patients for whom ectopic pregnancy was among the differential diagnoses should be followed with at least weekly β-hCG levels until β-hCG is no longer detectable in the serum.
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Section 7 Reproductive Surgery This may take up to several weeks, because a minimum decline in serial β-hCG concentration for a completed abortion ranges from 21% to 35% in 48 hours.52 A negative β-hCG value is the only sure way to confirm complete resolution of the ectopic pregnancy. There have been reports of tubal rupture with β-hCG levels as low as 5 mIU/mL.53 Of all women with ectopic pregnancies who present with symptoms, about 50% will have β-hCG levels above the discriminatory zone and are therefore diagnosed within a single evaluation.3 The remaining 50% of women with ectopic pregnancies who seek medical attention will be found to have β-hCG levels below the discriminatory zone, and ultrasound is usually nondiagnostic. At this point in time, the sensitivity of transvaginal ultrasound for the diagnosis of intrauterine pregnancy, spontaneous miscarriage, and ectopic pregnancy has been shown to be only 25% to 33% and the predictive value is low.54
Laparotomy versus Laparoscopy Laparoscopy has become the most common surgical approach to ectopic pregnancy, primarily due to the increased comfort level most gynecologic surgeons have gained with the laparoscopic approach. However, laparotomy remains the treatment of choice for the hemodynamically unstable patient with a ruptured ectopic pregnancy. Laparotomy versus laparoscopy for the treatment of ectopic pregnancy has been compared in three prospective, randomized trials.57–59 Each concluded that the laparoscopic approach is superior to laparotomy. Laparoscopy resulted in less blood loss, less analgesia requirement, and a shorter duration of hospital stay compared to laparotomy. Laparoscopy was also found to be less costly in all three trials. Not surprisingly, a Cochrane review of the surgical treatment of ectopic pregnancy likewise concluded that laparoscopy is the treatment of choice for eligible patients.60
Screening Asymptomatic Patients There may be some advantage to screening patients at high risk for ectopic pregnancy before the development of symptoms.55 Risk factors include previous history of ectopic pregnancy, tubal surgery, PID, sterilization, current IUD, and known tubal disease seen by hysterosalpingography or laparoscopy. In a study of 143 symptom-free women with these risk factors, screening was started before 7 weeks’ gestation with serial β-hCG measurements and ultrasound studies. In this particular study, 5.6% of the women were diagnosed with ectopic pregnancies. It is yet to be established that the potential benefits of this approach, including decreasing the risk of complications and patient reassurance, outweighed the drawbacks of false-positive diagnoses, increased costs, and increased emotional stress.56 For this reason, universal screening of women at increased risk for ectopic pregnancy cannot be recommended at this time.
TREATMENT Before the twentieth century, ectopic pregnancy was nearly always fatal, due to late diagnosis and absence of effective treatment options. Today, the primary goal of accurate and expeditious diagnosis is to limit morbidity and eliminate mortality associated with this condition. Early diagnosis of ectopic pregnancy makes a greater number of treatment options available to the physician and patient. Instead of the traditional treatment with laparotomy and fallopian tube resection (salpingectomy), clinically stable patients can often be treated with minimally invasive surgery (i.e., laparoscopy) and tubal conservation (salpingostomy). Alternatively, these patients may be candidates for medical therapy with methotrexate. In experienced hands, these modern treatment modalities appear to have comparable success rates, while maintaining the potential for future fertility.
Hemodynamic Stabilization
716
All patients suspected of having an ectopic pregnancy should have established adequate intravenous access for prompt crystalloid fluid hydration should intra-abdominal hemorrhage result in hemodynamic instability. Before surgery, the patient’s blood type should be determined and she should be cross-matched for several units of packed red blood cells in anticipation of further surgical losses.
Exploratory Laparotomy: The Unstable Patient
Exploratory laparotomy is still indicated for the treatment of the hemodynamically unstable patient in whom a ruptured fallopian tube has caused extensive intraperitoneal bleeding, leading to intravascular volume depletion. These patients present to the emergency room in distress, with hypotension and tachycardia; if intervention is not immediate, they may develop hypovolemic shock. Prompt evaluation and stabilization should be followed by expeditious surgery under general anesthesia. Although laparotomy is usually the most expedient approach, if hemodynamic stability can be reestablished with intravenous therapy, some experienced gynecologists find the laparoscopic approach satisfactory even with a ruptured ectopic pregnancy and associated hemoperitoneum as long as a large-bore (10-mm) suction– irrigator is available to allow adequate visualization of the pelvis. Regardless of approach, fluid and blood product replacement is the first priority in any patient exhibiting early signs of hemorrhagic shock. Large-bore IV lines should be placed, and the patient’s volume loss should be aggressively replaced. The patient should be cross-matched for at least 4 units of packed red blood cells before initiation of surgery, because additional volume losses may be expected once the abdomen is open and there is no pressure tamponade. Packed red blood cell transfusion should be initiated at the discretion of the anesthesiologist based on the patient’s physiologic condition and need for colloid fluid repletion, keeping in mind that young, healthy patients can usually tolerate anemia well. With every 4 units of packed red blood cells, 2 units of fresh frozen plasma are often transfused to replace clotting factors. The patient’s blood count and coagulation profile should be monitored closely throughout the case. Laparotomy via a pfannensteil incision will usually allow expeditious entry into the peritoneal cavity. On visualization of the pelvic structures, the site of implantation of the ectopic pregnancy should be immediately identified. A Kelly forceps (“clamp”) is then placed at the proximal portion of the fallopian tube, at the uterine cornu. This should virtually eliminate further blood loss, because most of the blood supply to the fallopian tube comes from branches of the uterine artery. A second Kelly clamp can then be placed along the mesosalpinx, meeting the end of the first clamp, so that all vessels within the mesosalpinx are occluded. Alternatively, a succession of Kelly clamps can be used to clamp the mesosalpinx as close to the tube as possible,
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Chapter 48 Ectopic Pregnancy Table 48-2 Salpingectomy via Laparotomy or Laparoscopy — Surgical Steps Suprapubic Pfannensteil incision made for laparotomy Fallopian tube elevated using Allis or Babcock clamp Mesosalpinx clamped with succession of Kelly clamps or hemostats, just below the fallopian tube Tube removed at site of uterine attachment close to cornua Interrupted 2-0 or 3-0 delayed-absorbable suture (e.g., Vicryl) used for closure of pedicles Inspection for hemostasis or Laparoscopic trocar ports placed (umbilical and at least 2 additional) for laparoscopic approach Fallopian tube grasped and elevated distally with endo-grasper Tube cauterized and then transected at cornual end, close to uterus Mesosalpinx coagulated with bipolar cautery and divided as close as possible to fallopian tube Dissection can proceed from cornual end to distal fimbria or from fimbriated end toward proximal tube Specimen placed in endoscopic bag and removed via large port site
as described by Damario and Rock.61 The entire tube and the ectopic gestation are then excised as one specimen. The pedicles are suture ligated with 2-0 or 3-0 vicryl or other synthetic absorbable suture. After assuring hemostasis, the pelvis should be evacuated of blood and clots, which can total up to several liters of blood loss (Table 48-2). Laparotomy can be the preferred approach for reasons other than hemodynamic instability. Other clinical indications include (1) multiple previous pelvic surgeries with documented or highly suspected extensive pelvic adhesions; (2) an underlying medical condition precluding laparoscopy; (3) an ectopic pregnancy that is outside the fallopian tube, in which case resection via laparoscopy is technically difficult; and (4) inadequate equipment or experience to safely remove the ectopic pregnancy laparoscopically.
Laparoscopic Approach Laparoscopy is the most common technique used for the surgical treatment of the majority of ectopic pregnancies. In general, at least three puncture sites are necessary to allow for adequate manipulation of the affected tube and the site of excision. This usually includes a laparoscope port placed at the umbilicus and two additional 5-mm instrument ports. One instrument port is placed in the midline 4 cm above the pubic symphysis, and a lateral port is place approximately 8 cm above the pubic symphysis and 8 cm lateral to the midline (to avoid the inferior epigastric vessels) on the side contralateral to the ectopic pregnancy. One of these incisions often needs to be enlarged to allow for the removal of the excised specimen, especially in the case of salpingectomy. An endoscopic pouch can be used to facilitate the collection of the specimen in the pelvis and ease its removal without fragmentation through a 10-mm port site. Salpingectomy
The surgical steps of laparoscopic salpingectomy are similar to those performed via laparotomy.56,62 Blood and clots present in the pelvis are removed with irrigation and suction so that the
involved tube can be adequately visualized. The involved tube is grasped near the end where cutting will be initiated. If possible, the tube is resected starting proximally at the uterine cornu and continuing until the fimbrial end is reached. With less than ideal exposure, resection can proceed in the opposite direction. Likely the easiest way to ensure tubal transection and closure at the uterine attachment is by using bipolar cautery. With the coagulation technique, the mesosalpinx is coagulated with bipolar cautery and then divided. If a single coagulation-cutting instrument is not available, this can be accomplished using bipolar forceps and then laparoscopic sheers. The mesosalpinx should be transected as close as possible to the fallopian tube so that vessels within the mesosalpinx, which are providing blood flow to the ovary, are not compromised. Other techniques for laparoscopic salpingectomy involve the use of endoscopic stapling devices as well as pretied endoscopic ligatures. Salpingostomy
Conservative surgical management of ectopic pregnancy can be accomplished by either salpingostomy or by segmental resection of the involved segment of fallopian tube. Segmental resection has mostly been used in patients with isthmic ectopic pregnancies because in this portion of the tube the lumen is narrower and the muscularis is thicker than in the ampullary region.63 This anatomic difference may lead to increased tubal obstruction after linear salpingostomy performed on this segment of the tube. The purpose of segmental resection is to retain the possibility of reanastomosis of the tubal segments using microsurgical technique, a procedure that may be undertaken either at the time of the initial surgery or during a subsequent surgery. The continued improved success of IVF, which is altogether able to bypass the fallopian tube, has made tubal reconstruction after ectopic pregnancy less utilized and not as practical. Salpingostomy, on the other hand, has become the standard procedure for laparoscopic resection of an ectopic pregnancy, although this technique can be performed via laparotomy as well. After identification of the ectopic gestation, the fallopian tube is immobilized by an atraumatic laparoscopic grasper. A 10- to 15-mm linear incision is then made on the antimesenteric surface of the fallopian tube, over the most distended portion of the tube. The linear incision can be made by laser, ultrasonic scalpel, unipolar needle cautery, or the tip of unipolar scissors. The ectopic pregnancy can then be removed by irrigating it out from the tube, or with blunt dissection, until the specimen protrudes through the opening and can be grasped for removal. The ectopic pregnancy tends to be found in the proximal portion of the distended fallopian tube, with blood clot and hemorrhage extending distally and accounting for most of the tubal enlargement. Therefore, it is important to ensure that all trophoblastic tissue is completely extracted from the tube, so as to not risk a persistent ectopic pregnancy. Tissues should be removed atraumatically because physical removal with surgical graspers may result in false plains, resulting in a greater incidence of retained trophoblastic tissue. Bleeding from the incision edge and ectopic pregnancy site can be controlled using bipolar or, if necessary, unipolar electrosurgery. Electrosurgery should be limited as much as possible to prevent further tubal damage. Another technique to minimize bleeding is to inject the tubal mesentery under the ectopic pregnancy before making the incision with 10 mL of a dilute
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Section 7 Reproductive Surgery Table 48-3 Laparoscopic Salpingostomy — Surgical Steps Laparoscopic trocar ports placed (umbilical, suprapubic, and at least one additional in lower quadrant contralateral to ectopic site) Evacuation of hemoperitoneum with suction irrigator Fallopian tube grasped and kept taut with atraumatic endo-grasper Laser, unipolar cautery, or edge of endosheers used to make linear salpingostomy incision along antimesenteric wall of tube Hydrodissection or gentle tubal compression to extrude products of conception Tissue placed in endoscopic bag and removed from abdominal cavity Irrigation of tube with minimal use of cautery (micro-tip best) Tube left open to heal by secondary intention
vasopressin solution (10 U in 50 mL physiologic saline solution).61 The temporary local vasospasm induced by this method is designed to minimize the need for electrosurgery and thus limit damage to tubal mucosa during ectopic pregnancy removal. After tissue removal and achievement of hemostasis, the tube is gently irrigated and left to close by secondary intention. The salpingostomy site closes effectively and rapidly by secondary intention with minimal risk of adhesions. Closing the salpingostomy with suture has not been shown to be beneficial during laparotomy or laparoscopy and might actually increase the risk of tissue ischemia and adhesion formation.64–66 A prospective study failed to show a difference between suturing and not suturing the salpingostomy site after laparoscopic removal of ectopic pregnancies in terms of tubal patency rates, postoperative adhesion rates, or cumulative pregnancy rates (Table 48-3).66 Whether performed by laparotomy or laparoscopy, the fertility outcome after linear salpingostomy is satisfactory. After salpingostomy performed by either approach, the intrauterine pregnancy rate is approximately 60% and the recurrent ectopic pregnancy rate is 15%.14 Comparisons of reproductive outcomes following different treatment approaches are discussed here. Persistent Ectopic Pregnancy
718
Although salpingostomy has a high success rate in terms of subsequent tubal patency and intrauterine pregnancy, incomplete resolution of the pregnancy, termed persistent ectopic pregnancy, occurs in 5% to 20% treated by this method.67–69 In one study, the risk of persistent ectopic pregnancy was double for patients treated with laparoscopic salpingostomy compared to patients treated with salpingostomy performed via laparotomy.14 After treating an ectopic pregnancy with salpingostomy, the β-hCG level should be checked on postoperative day 1. A decrease of less than 50% from the initial preoperative β-hCG level is associated with a relative risk of 3.51 for persistent products of conception.70 In this same series, there were no cases of persistent ectopic pregnancy when the postoperative day 1 β-hCG decreased by more than 76%. To ensure complete resolution of the ectopic pregnancy, the β-hCG level should be repeated weekly until it is no longer detectable. Failure of the β-hCG to drop to undetectable levels after surgery is an indication that active trophoblastic tissue has been left behind. Risk factors for developing a persistent ectopic pregnancy include a very early gestation, a small ectopic pregnancy of less than 2 cm, or a high concentration of β-hCG preoperatively.
Options for treatment of a persistent ectopic pregnancy include medical therapy or a second surgery. In general, if there are no signs indicating tubal rupture (which may occur even in the setting of a dropping β-hCG), medical treatment with methotrexate, using a single intramuscular dose, is preferable. Use of prophylactic methotrexate immediately after conservative surgery has been advocated by some and its use supported by one randomized trial, which showed a decrease in the rate of persistent ectopic pregnancy from 14.5% to 1.9% with singledose methotrexate (1 mg/kg IM).71 A recent decision-analysis found that prophylactic methotrexate resulted in fewer cases of tubal rupture and fewer procedures at a lower cost compared with observation alone.72 In a clinical setting where the rate of persistent ectopic pregnancy is greater than 9% with observation after surgery, the incidence of persistent ectopic pregnancy is less than 5% after prophylactic methotrexate, the probability of ectopic rupture is greater than 7.3% with persistent ectopic pregnancy, and the complication rate associated with prophylactic methotrexate is less than 18%, the use of prophylactic methotrexate optimizes the treatment. If these conditions are not met, observation alone is the better strategy. Until more data are available, following serial β-hCG levels without administering prophylactic methotrexate remains a reasonable strategy. Salpingectomy versus Salpingostomy
The decision to perform a salpingectomy as opposed to a salpingostomy in the surgical treatment of ectopic pregnancy is often difficult. If the tube is ruptured or appears extensively damaged, or in cases of large tubal pregnancies (>5 cm), salpingectomy is preferred and may be the only option. Similarly, if hemorrhage at the site of implantation cannot be controlled with conservative surgery, salpingectomy is appropriate because extensive coagulation of bleeding sites can result in extensive destruction of the tubal lumen. Women who have had a previous ectopic pregnancy at the same site and those who do not wish to be pregnant in the future are also candidates for salpingectomy. In these cases, the option of “ligating” the contralateral tube for contraceptive reasons should discussed with the patient prior to surgery. In patients who desire future fertility, the decision to perform salpingectomy or salpingostomy should be based on several additional considerations. Salpingectomy is often the preferred procedure in patients with extensive tubal adhesion or a history of previous tubal surgery, including tubal anastomosis. The risk for a repeat ectopic pregnancy is the same for a woman if the affected tube is removed or conserved because the risk factors for ectopic pregnancy usually affect both tubes. However, it is likely that conservation of the affected tube increases future fecundity. In women with a history of two or more ectopic pregnancies, early referral for IVF likely gives the best pregnancy success.
Medical Management with Methotrexate Methotrexate has proven to be a safe and effective method of treating ectopic pregnancy. First introduced in 1982, it has become a common mode of treatment for appropriately selected patients. The primary advantage to medical therapy is the chance to avoid the morbidity and risks associated with surgery. In addition to its use as primary treatment for ectopic pregnancy, methotrexate is
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Chapter 48 Ectopic Pregnancy also used for the treatment of persistent ectopic pregnancy after salpingostomy, as a prophylactic method to decrease the risk of persistent ectopic pregnancy after conservative surgery, and as a primary treatment of ectopic pregnancies in unusual locations.
readily referred to IVF for a presumed tubal factor, when one may not actually exist. In addition, the presumptive treatment of women at risk for ectopic pregnancy does not result in a reduction in cost, side effects, or time saved.76
Mechanism of Action
Indications and Contraindications
Methotrexate acts to inhibit rapidly dividing cells, specifically arresting mitosis of the cytotrophoblasts of the ectopic pregnancy. It is a folic acid antagonist that inhibits the enzyme dihydrofolate reductase. Dihydrofolate reductase reduces folate to tetrahydrofolate by the addition of single carbon groups, which are subsequently transferred in the synthesis of DNA and RNA precursors. By blocking this enzyme, methotrexate leads to the depletion of cofactors required for DNA and RNA synthesis. With interruption of both DNA and RNA synthesis and impairment of the synthesis of critical proteins necessary for cell survival, methotrexate targets cells in many parts of the cell cycle.73 Methotrexate also causes the buildup of dihydrofolate polyglutamates in the cell, which both acts as a toxic substance itself and prolongs the action of methotrexate within cells.73,74 Leucovorin (folinic acid) is sometimes used to “rescue” cells in which dihydrofolate reductase has been inactivated by methotrexate. This reduced form of folic acid enters cells via a carrier-mediated system and does not require reduction by dihydrofolate reductase for the conversion to active folate cofactors for DNA and RNA synthesis. For these reasons, leucovorin prevents some otherwise prohibitive side effects and allows for the administration of higher methotrexate doses. When treating an ectopic pregnancy with high-dose or multidose regimens of methotrexate, leucovorin rescue therapy is often added. Methotrexate is predominantly cleared by the kidney and excreted in the urine, so the medication should be used with great caution and with adjusted doses in patients with renal compromise.74
Methotrexate is an acceptable form of treatment for patients with ectopic pregnancy who have no evidence of tubal rupture, including hemodynamic instability or signs of hemoperitoneum. The patient must also be reliable enough to return as required for follow-up care. To minimize the risk of tubal rupture after the initiation of medical therapy, relative contraindications for the use of methotrexate have been described.77 Although not all clinicians agree, many avoid using methotrexate in the presence of an adnexal mass greater than 3.5 cm at its greatest dimension, fetal cardiac motion visible on ultrasound, or β-hCG greater than 15,000 mIU/mL.77 Absolute contraindications to methotrexate therapy include evidence of immunodeficiency, damage to organs that metabolize methotrexate (i.e., liver and kidney), preexisting conditions that could be exacerbated by methotrexate (e.g., peptic ulcer disease, blood dyscrasias, active pulmonary disease), and breastfeeding (Table 48-4).
Need for Definitive Diagnosis
Methotrexate Treatment Protocols
In an attempt to expedite treatment for women with abnormal pregnancies, some clinicians have used methotrexate presumptively before making a definitive diagnosis. The most common clinical scenarios where this practice is employed are (1) in the absence of signs of a normal intrauterine pregnancy and β-hCG above the discriminatory zone, and (2) with a pleateauing β-hCG level below the discriminatory zone. Although such a strategy does avoid invasive intervention, it is not recommended. Presumed diagnosis of ectopic pregnancy has been shown to be inaccurate about 40% of the time.75 Therefore, if methotrexate were used without prior confirmation of an ectopic pregnancy, a large number of patients would receive this chemotherapeutic agent unnecessarily. In addition, methotrexate has about a 30% failure rate when used for early pregnancy termination, so it may be inadequate treatment for an abnormal intrauterine pregnancy.75 Should the pregnancy ultimately prove to be viable, the risk of congential anomalies is significant, because methotrexate is a known teratogen. Another problem with presumptive treatment is that an incorrect diagnosis will lead to assignment of an erroneous diagnostic label to a patient, which may have implications for her future care: a patient with an ectopic pregnancy may be more
For the treatment of ectopic pregnancy with methotrexate, intramuscular injection is the preferred method of administration. Preliminary reports of oral administration have reported successful resolution of ectopic pregnancy, but this mode of administration is not well-studied.80
Pretreatment Evaluation
Certain baseline laboratory values should be evaluated before administering methotrexate. Patients should be screened with a complete blood count, liver function tests, and serum creatinine. A chest x-ray should be performed in women with a history of pulmonary disease due to their risk of developing interstitial pneumonitis. Patients should be excluded from medical treatment if they are found to have aspartate transaminase greater than 50 or 2 times normal; creatinine level greater than 1.3 to 1.5 mg/dL, white blood cell count less than 3,000/μL, or platelet count less than 100,000/μL.78,79
Table 48-4 Absolute Contraindications to Methotrexate Therapy Breastfeeding Overt or laboratory evidence of immunodeficiency Alcoholism, alcoholic liver disease, or other chronic liver disease Preexisting blood dyscrasias (bone marrow hypoplasia, leukopenia, thrombocytopenia, significant anemia) Known sensitivity to methotrexate Active pulmonary disease Peptic ulcer disease Hepatic, renal, or hematologic dysfunction Adapted from ACOG: Medical Management of Tubal Pregnancy. Washington, DC, ACOG Practice Bulletin No. 3, 1998.
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Section 7 Reproductive Surgery The two most common regimens employed for the treatment of ectopic pregnancy are the multidose protocol and the singledose protocol. Under the multidose protocol, methotrexate is administered as the sodium salt at a dose of 1 mg/kg per day, intramuscularly, on days 1, 3, 5, and 7 of treatment.81 Due to the relatively large overall dose, leucovorin is used to prevent cell toxicity and is given at a dose of 0.1 mg/kg intramuscularly on alternating days (days 2, 4, 6, and 8). Patients receive up to four doses (1 methotrexate/1 leucovorin) until the β-hCG decreases by at least 15% on two consecutive measurements, 2 days apart. Consequently, some patients may only require one or two doses, and others need the full four-dose course. All patients need to be followed until the β-hCG is no longer detectable in the serum to confirm complete resolution of the ectopic gestation. In select cases, a second four-dose course may be given 1 week later if there is an increase or plateau in two consecutive β-hCG values; at such a point, however, most clinicians would proceed to surgical treatment. A single-dose regimen of methotrexate was more recently introduced, with the benefit of simplified administration and less frequent need for patient follow-up.82 Under this protocol, a patient is given an intramuscular methotrexate dose of 50 mg/m2 based on the patient’s body surface area: [Height(cm) × Weight(kg)] BSA (m ) = 3600 2
冢
冣
1⁄2
No leucovorin rescue is given. The single-dose regimen is somewhat of a misnomer because a second dose may be administered after 1 week if the β-hCG value does not decline by at least 15% between days 4 and 7 after initial methotrexate injection. It has been shown that using the single-dose protocol, approximately 20% of women require more than one dose to completely resolve their ectopic gestation.83 Again, once a treatment response has been documented with serially decreasing β-hCG levels, patients are followed with surveillance β-hCG measurements until no longer detectable in serum (Tables 48-5 and 48-6).
Table 48-5 Multidose Methotrexate Protocol Treatment Day
Laboratory Tests
Intervention
Pretreatment
β-hCG, CBC with differential, LFTs, creatinine, type and screen
Rule out SAB Rhogam if Rh-negative
1
β-hCG
MTX 1.0 mg/kg
2 3
LEU 0.1 mg/kg β-hCG
4 5
LEU 0.1 mg/kg β-hCG
6 7
720
MTX 1.0 mg/kg if <15% decline Day 3 to Day 5. If >15% stop treatment and start surveillance. LEU 0.1 mg/kg
β-hCG
8
MYX 1.0 mg/kg if <15% decline Day 5 to Day 7. If >15% stop treatment and start surveillance. LEU 0.1 mg/kg
Surveillance every 7 days (until β-hCG <5) β-hCG, β-human chorionic gonadotropin; CBC, complete blood count; LFTs, liver function tests; SAB, spontaneous abortion; MTX, methotrexate; LEU, leucovorin.
Table 48-6 Single-dose Methotrexate Protocol Treatment Day
Laboratory Tests
Intervention
Pretreatment
β-hCG, CBC with differential, LFTs, creatinine, type and screen
Rule out SAB Rhogam if Rh-negative
0
β-hCG
MTX 50 mg/m2* IM
4
β-hCG
7
β-hCG
Side Effects
Although safe, methotrexate does have several dose-related side effects. As a folic acid analogue, methotrexate affects rapidly dividing cells, especially those of the gastrointestinal tract and the bone marrow. At methotrexate doses used to treat ectopic pregnancies, common symptoms include cramping abdominal pain, vaginal bleeding or spotting, gastrointestinal symptoms including nausea, vomiting, and indigestion, and general symptoms such as fatigue, lightheadedness, or dizziness.77,79 Major side effects are uncommon and include impaired liver function, skin sensitivity to light, stomatitis, gastritis and enteritis, temporary hair loss, bone marrow suppression, and pneumonitis.3,14,60 Hemorrhagic enteritis is manifest by nausea, vomiting, bloody diarrhea, and weight loss. Destruction of bone marrow precursors puts the patient at risk for developing thrombocytopenia, reticulocytopenia, lymphopenia, and granulocytopenia, and in the most severe cases can lead to risk of lifethreatening hemorrhage and systemic infections. Rare cases of alopecia and anaphylactoid reaction have also been described.84,85 Fortunately, major side effects reported with methotrexate used to treat ectopic pregnancy are very uncommon. In one study, 2% of patients developed stomatitis and 3% had transient
MTX 1.0 mg/kg if <15% decline Day 1 to Day 3. If >15%, stop treatment and start surveillance.
MTX 50 mg/m2* IM if β-hCG <15% decrease Day 4 to Day 7
Surveillance every 7 days (until β-hCG <5) β-hCG, β-human chorionic gonadotropin; CBC, complete blood count; LFTs, liver function tests; MTX, methotrexate; SAB, spontaneous abortion. *Dose calculated by body surface area using nomogram.
elevation of transaminase levels, all of which resolved spontaneously.82 The single-dose regimen appears to be associated with fewer side effects (OR=0.44; 0.31–0.63).86 However, when adjusted for initial β-hCG values, the prevalence of side effects was comparable for those who received single-dose and multidose methotrexate. Clinical Course after Treatment
It is important for both patients and clinicians to be aware of the clinical course of ectopic pregnancies after methotrexate treatment. An increase in abdominal pain 6 to 7 days after receiving the medication is reported by one third to two thirds of patients.14,78,87 This “separation” pain is attributable to tubal distension from tubal abortion or hematoma formation. As long as other aspects of the patient’s condition remain stable,
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Chapter 48 Ectopic Pregnancy separation pain may be treated with pain medications and does not warrant surgical intervention.88 The β-hCG levels may plateau, or even rise initially, after methotrexate injection. This is believed to occur because of continued hormonal production by syncytiotrophoblastic cells, despite mitotic arrest induced by methotrexate in the cytotrophoblasts.89 Similarly, on ultrasound examination, the gestational mass may appear to enlarge, owing in part to hemorrhage distending the tubal lumen. Efficacy of Methotrexate
Methotrexate is effective in the treatment of ectopic pregnancy. Overall, methotrexate has been shown to be more effective with absence of live embryo, smaller gestational mass (<3.5 cm), less color Doppler flow to the adnexal mass, and lower initial β-hCG level, though the absolute value for β-hCG varies among studies.87,90–92 Reviews on the subject have demonstrated that patients who are administered methotrexate therapy as single or variable dose may expect an 87% to 93% success rate, a posttreatment tubal patency rate of about 75% to 81%, with a future pregnancy rate of about 60% and a recurrent ectopic pregnancy rate of 7% to 8%.4 However, the majority of trials have been open label with no direct comparison between regimens. A meta-analysis, including data from 1327 women treated with methotrexate for ectopic pregnancy, compared the singledose and multidose regimens.86 The overall success rate, defined as the avoidance of surgical intervention, for the medical therapy was 89%; the success rate of the multidose therapy was 92.7% and of the single-dose was 88.1%, a statistically significant difference. The use of the single-dose regimen was associated with a significantly greater chance of failed medical management compared to the use of the multidose regimen (OR 1.71; 1.04–2.82). However, when the analysis was adjusted to account for factors independently affecting success rates such as initial β-hCG and the presence of embryonic fetal cardiac activity, it was noted that the failure rate of a single-dose regimen was even higher compared to the multidose regimen (OR 4.74, 1.77–2.62). The frequency of actual dosing using the two protocols was also evaluated, showing that 15% of patients under a single-dose regimen actually received more than one dose of methotrexate. Variability in the number of doses necessary for successful resolution of the ectopic pregnancy was also evident among patients treated with the multidose protocol. The above data support the contention that single-dose methotrexate may be less effective and that optimal dosing for treatment of ectopic pregnancy may lie somewhere between these two protocols (e.g., a two-dose regimen). Methotrexate Efficacy Compared to Surgery
Several studies have compared medical management to surgical management.93,94 Multidose methotrexate therapy appears to be comparable in effectiveness to laparoscopic salpingostomy. In a multicenter, randomized, prospective trial of 100 women with laparoscopically confirmed ectopic pregnancies, 82% of those who received methotrexate were successfully treated with a single course, 4% required a second course, and 14% required surgical intervention for active bleeding or tubal rupture.93 Of the women in the salpingostomy arm, 72% were successfully treated with salpingostomy alone, 8% required conversion to
salpingectomy for persistent bleeding, and 20% required adjuvant methotrexate for persistent trophoblastic tissue. Not all studies have found that methotrexate management is equivalent to surgical management. In a smaller, randomized trial comparing single-dose methotrexate to laparoscopic salpingostomy, a 65% success rate in the methotrexate group was noted, compared to a 93% success rate in the laparoscopic salpingostomy group, calling into question the effectiveness of the single-dose regimen.95 A retrospective study from a university hospital serving an indigent population likewise compared the success of singledose methotrexate with that of surgical treatment.96 The overall success rate for those receiving methotrexate was significantly lower than for the conservative laparoscopic surgical group (79% vs. 90%, respectively), and 11% of patients treated medically required a second methotrexate dose.
Direct Injection of Methotrexate and Other Agents Direct injection of methotrexate into the ectopic gestational sac can be done laparoscopically, hysteroscopically, via transcervical tubal cannulation, or transvaginally under ultrasound guidance.97–100 Direct injection of methotrexate has the advantage of delivering a higher dose of medication precisely into the ectopic implantation site, reducing systemic absorption and resultant side effects. However, unlike intramuscular administration, this mode of drug delivery is invasive and requires some degree of expertise and often anesthesia. There is no evidence that direct injection is superior to systemic methotrexate. Likewise, a review of many small studies by the Cochrane Group concluded that local methotrexate was less effective in eliminating an ectopic pregnancy when compared to laparoscopic salpingostomy. Based on the overall tolerability of the approach, systemic methotrexate continues to be the most accepted medical treatment modality. Other Agents
Injection of other agents into the site of an ectopic pregnancy has been reported. Ultrasound-guided injection of potassium chloride has been shown to lead to cessation of cardiac activity and subsequent resorption of ectopic pregnancies.101,102 However, because potassium chloride does not affect the growth of trophoblastic tissue, this tissue may continue to proliferate, possibly leading to fallopian tube rupture.103 Laparoscopic injection of hyperosmolar glucose has also been reported to be successful in a small series of patients,104 but it is less successful than laparoscopic salpingostomy.105 Because most of these reports involve small numbers of patients, subsequent tubal function and reproductive success remain uncertain. None of these alternative methods are currently in widespread use.
Expectant Management Prior to modern methods of early diagnosis of ectopic pregnancy and prompt interventions, many ectopic pregnancies likely spontaneously resolved with no treatment. In the 1950s, Lund106 randomized patients to expectant management versus surgical treatment and reported a 57% success rate of spontaneous resolution of the ectopic pregnancy in the nonintervention group. However, those patients whose ectopic pregnancies did not resolve on their own experienced significant symptoms and presented with hemoperitoneum and tubal rupture.
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Section 7 Reproductive Surgery A recent review of 10 studies that prospectively examined the efficacy of expectant management included 347 patients.14 These were patients who were hemodynamically stable and whose β-hCG levels were documented to be decreasing by serial measurements. Although there was some variation between the studies in the confirmation of diagnosis, size, and location of the ectopic pregnancy, the overall success rate was 69%, with a range of 47% to 100%. Some investigators have attempted to identify prognostic factors that predict success of expectant management.107,108 Although there appears to be increased success of spontaneous resolution with lower initial β-hCG and absence of a visible sac on ultrasound, there are still no established criteria for the inclusion and exclusion of patients. Despite close follow-up, and even in the context of declining β-hCG levels, tubal rupture may still occur.14 One study of a large cohort of women with ectopic pregnancies was able to categorize women into two groups: those who presented acutely and those who had a chronic presentation.109 Those with the chronic presentation often had a delayed diagnosis of ectopic gestation, but were also found to have a less acute clinical course with a lower chance of rupture. The authors speculated that this difference may be due to factors such as differences in the invasive nature of the trophoblast, the location of implantation, or host defenses. Both clinicians and patients need to be aware of the potential risks to choosing expectant management over proven therapies of either conservative surgery or methotrexate. Until further studies are able to elucidate the etiology of these potentially different clinical entities and can demonstrate that the approach to treatment should be different, expectant management should be used only with extreme caution after informed consent.
Treatment of Ectopic Pregnancies in Locations Other than the Tube
722
the most lateral edge of the uterine cavity, and a thin myometrial layer surrounding the chorionic sac.111,112 Surgical Treatment
Traditional treatment of interstitial ectopic pregnancy was cornual resection via laparotomy, and this remains the approach for the unstable patient. A laparoscopic approach has been proposed in the treatment of the stable patient who does not desire medical management. Most techniques described in the literature involve injection of intramyometrial vasopressin to minimize blood loss, performance of a linear incision at the site of the ectopic pregnancy, and the use of hydrodissection to flush out the gestational products in one mass.110 Some authors advocate the closure of the cornual defect with sutures; others use electrocoagulation with closure by secondary intention.113 Successful hysteroscopic management of interstitial ectopic pregnancy has also been described.114 Medical Treatment
Studies of the use of methotrexate to treat interstitial ectopic pregnancy have yielded conflicting results. In a series of 14 patients with interstitial ectopic pregnancy, treatment with single-dose methotrexate was 100% successful, with only 1 patient requiring a second dose due to insufficient decline of β-hCG between days 4 and 7.115 In another review of 20 patients with interstitial ectopic pregnancy, treatment with methotrexate was only successful in 35%.53 In a review of 41 patients with interstitial ectopic pregnancy treated with systemic, local injection, or combined methotrexate therapy, the overall success rate was 83%, with faster resolution of β-hCG in patients treated with local injection.110 Based on these and other published reports, it appears that, in stable patients management of interstitial pregnancy with either laparoscopy or methotrexate using a multidose protocol are reasonable alternatives to laparotomy. Ovarian Pregnancy
Although most ectopic pregnancies are located within the fallopian tube’s ampullary, isthmic, or fimbrial portions, a small number implant in unusual sites. Of all ectopic pregnancies, about 2.4% are interstitial or cornual, 3.2% ovarian, and 1.3% abdominal, and less than 0.15% are cervical.6–8 With earlier and more accurate diagnosis of these rare ectopic pregnancies, a conservative approach to treatment in the hemodynamically stable patient is often feasible. Evidence for the management of ectopic pregnancy in each of these locations is summarized here. It is important to remember that due to the rarity of this condition, much of the primary evidence comes from case reports and short series of patients and not from randomized trials.
Ovarian ectopic pregnancies remain difficult to differentiate from tubal pregnancies before surgery because it is difficult with ultrasound to distinguish between ovarian and tubal masses. Due to ovarian vascularity, ovarian pregnancy tends to present earlier and often after having already ruptured.116 Grossly, an ovarian pregnancy can be mistaken for a bleeding corpus luteum cyst until pathologic confirmation of chorionic villi is obtained. The approach to the treatment of ovarian ectopic pregnancy has traditionally been laparotomy with oophorectomy. Wedge resection and the laparoscopic approach have been reported in recent years.117 Medical treatment with methotrexate has also been described with success.118
Cornual (Interstitial) Pregnancy
Abdominal Pregnancy
The interstitial part of the fallopian tube is the proximal portion that is embodied within the muscular wall of the uterus, measuring approximately 0.7 mm in width and 1 to 2 cm in length. Due to the surrounding myometrial layer, a gestation in this site may expand and not rupture until reaching 7 to 16 weeks in size.110 Clinically, a pregnancy implanted in this site is seen as a swelling lateral to the round ligament. Sonographic criteria suspicious for the diagnosis include an empty uterine cavity, a chorionic sac seen separately and more than 1 cm from
Abdominal pregnancies occur with an incidence of approximately 10 per 100,000 live births and 9 per 1000 ectopic pregnancies. The most common site of implantation is the pouch of Douglas, although abdominal pregnancies have been reported to occur in other parts of the peritoneal cavity, including the liver, spleen, and omentum. It is hypothesized that abdominal pregnancies occur after tubal pregnancy is extruded from the tube, with subsequent reimplantation of the conceptus on a nearby peritoneal surface.
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Chapter 48 Ectopic Pregnancy Although the traditional treatment of abdominal pregnancy has been by laparotomy, early diagnosis with ultrasound can sometimes allow for more conservative management. Recent case reports have described successful treatment of abdominal ectopic pregnancies with laparoscopy, some with additional adjuvant methotrexate.119–122 Cervical Pregnancy
The incidence of cervical pregnancy has been reported as approximately 1:1000 to 1:18,000 pregnancies. The cervix structurally consists of 90% collagen fibers with only a small amount of muscular tissue; it has a rich blood supply. As a result, the cervix has almost no ability to reduce hemorrhage by contraction. On spontaneous expulsion or therapeutic removal of a cervical pregnancy, severe hemorrhage can occur if appropriate precautions are not taken. Before surgical management with D&C, the substantial risk of postevacuation hemorrhage can be minimized by vascular occlusion, which has been successfully reported by transvaginal ligation of the cervical branches of the uterine arteries or angiographic embolization of the uterine arteries.123 Arterial embolization in the radiology suite offers the advantage of being less invasive compared to arterial ligation. The most common surgical approach for the treatment of cervical pregnancy is curettage, although successful hysteroscopic resection of a cervical pregnancy has also been reported.124 After removal of a cervical pregnancy, postprocedure bleeding can be controlled using a Foley balloon for tamponade, a technique that has been shown to be more effective than vaginal packing.125 In women who do not desire future fertility, hysterectomy reliably removes the cervical ectopic pregnancy and is probably the most reliable way to control procedure-related hemorrhage. In patients desiring future fertility, medical treatment of a cervical pregnancy might lower the risk of hemorrhage compared to surgery.123,126 Medical treatments that have been described include local injection of methotrexate, prostaglandins, or hyperosmolar glucose, with or without curettage.123,126,127 Local injection of methotrexate appears to offer some advantage over systemic administration in the treatment of cervical pregnancy. Whenever medical treatment is used, the physician must be prepared to control life-threatening hemorrhage by whatever means necessary, including hysterectomy, even in women who desire future fertility.
tube-sparing, conservative treatment with salpingostomy or methotrexate have approximately an equal risk of recurrent ectopic pregnancy in either tube. Likewise, the risk of a recurrent ectopic pregnancy after salpingectomy (7% to 17%) appears to be no greater than after salpingostomy (8% to 16%).14,136,137 In patients with a history of ectopic pregnancy, some factors appear to increase the risk of having a recurrent ectopic pregnancy even further, including a history of any pelvic surgery (including surgery for the first ectopic pregnancy) and a previous live birth or spontaneous miscarriage.133 In this study, it was surprising that the risk of a recurrent ectopic pregnancy was not further increased by a history of infections with gonorrhea or chlamydia, pelvic inflammatory disease, cesarean delivery, or pregnancy termination. One explanation for these findings is the possibility that the occurrence of the first ectopic pregnancy is a more sensitive marker for tubal damage from a subclinical pelvic infection than either cultures or clinical history. Subsequent Fertility
Subsequent fertility rates do not appear to be affected by whether the ectopic pregnancy is treated laparoscopically or by laparotomy. Several studies have failed to show a difference between subsequent intrauterine pregnancy rates in women treated with salpingostomy whether performed by laparoscopy (56% to 61%) or laparotomy (58% to 61%).14,57,59,138 With similar results in terms of fertility, laparoscopy (with its decreased blood loss, shorter hospital stay, and shorter postoperative recovery compared to laparotomy) has become the procedure of choice for the hemodynamically stable patient. Although it seems logical that subsequent fertility would be higher after salpingostomy compared to salpingectomy, several studies have not demonstrated this. In one study of combined data from nine retrospective studies, subsequent intrauterine pregnancy rates were no different after salpingostomy (53%) versus salpingectomy (49%).14 Another large retrospective study found no difference in subsequent intrauterine pregnancy rates after salpingostomy (36%) versus salpingectomy (40%), as long as the remaining tube was patent.136 When the opposite tube was blocked or absent, the intrauterine pregnancy rate after salpingostomy was decreased by half (18%).136 A third study found that the intrauterine pregnancy rate after salpingostomy was almost twice that after salpingectomy; however, these differences
REPRODUCTIVE OUTCOME AFTER ECTOPIC PREGNANCY
Table 48-7 Recurrent Ectopic Pregnancy According to Treatment
Fertility after Surgical Treatment Study
Risk Factor
Butts et al.133 Ego et al.134 Tulandi135
History of previous ectopic pregnancy One previous Two previous
Recurrent Ectopic Pregnancy Rate
Recurrent Ectopic Pregnancy
The risk of a recurrent ectopic pregnancy ranges from 10% to 27%, which represents a fivefold to tenfold increase in risk compared to the general population (Table 48-7).128–132 It is not surprising that ectopic pregnancies tend to recur, because many ectopic pregnancies are the result of abnormal fallopian tube function. Women who have undergone salpingectomy for an ectopic pregnancy have an increased risk of developing another ectopic pregnancy in the remaining tube, due to the likely bilateral nature of the underlying process (see Table 48-7). Those who undergo
4
Pisarska et al.
4
Pisarska et al. Barnhart et al.38 Barnhart et al.38 Yao & Tulandi14
After treatment of ectopic pregnancy with Methotrexate Laparoscopic Salpingostomy Salpingectomy Laparotomy Salpingostomy Salpingectomy
10–27% 13% 28%
6–8% 13% 17% 16% 10%
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Section 7 Reproductive Surgery Table 48-8 Indications for Salpingectomy Tubal rupture Extensive tubal damage Dense tubal adhesions Clubbed or otherwise damaged fimbriae Uncontrolled hemorrhage from tube after attempt at salpingostomy Recurrent ectopic pregnancy in same tube Undesired future fertility
were not statistically significant on multivariate analysis.40 A recent study found a higher cumulative pregnancy rate after salpingostomy (88%) compared to salpingectomy (66%).137 In the absence of results from a randomized study, it makes sense to perform a salpingostomy whenever possible in the presence of a relatively normal-appearing tube in patients desiring future fertility. However, if the tube is ruptured or severely damaged, or the patient does not desire future fertility, salpingectomy is often the best, and sometimes the only, surgical option (Table 48-8). If both tubes are suspected to be damaged, the physician may choose to discuss with the patient the option of performing a bilateral salpingectomy at the time of ectopic resection with the future use of IVF. Given the dramatic recent increase in success with IVF, it is rapidly becoming the treatment of choice for any woman with tubal damage or a history of multiple ectopic pregnancies.
Fertility after Methotrexate Treatment Reproductive outcome appears to be similar after methotrexate therapy compared to surgical therapy, and there is a suggestion that the recurrent ectopic pregnancy rate may be lower. The tubal patency rate after methotrexate treatment for ectopic pregnancy is high, ranging from 75% to 80% in a review of 40 studies of single-dose, variable-dose, and direct-injection regimens.4 In this same review, the subsequent intrauterine pregnancy rate was found to be 57% to 61%, and the ectopic pregnancy rate was 6% to 8%. In an 18-month follow-up study comparing multidose systemic methotrexate with laparoscopic salpingostomy, the cumulative spontaneous intrauterine pregnancy rate was 36% in the methotrexate-treated group and 43% in the laparoscopic salpingostomy group.137 In a small randomized trial,
the overall rate of intrauterine pregnancy rate (including patients who conceived with ART) appeared higher and the ectopic pregnancy rate lower after methotrexate treatment compared to laparoscopic salpingostomy, although the study lacked the statistical power to reach definitive conclusions.138 Reproductive outcome can be safely concluded to be no worse after methotrexate than after salpingostomy in terms of subsequent intrauterine pregnancy rates. There is a suggestion that the recurrent ectopic pregnancy rate may be lower after methotrexate treatment. These facts should be incorporated into the decision-making process when weighing the treatment options for a patient with an ectopic pregnancy.
SUMMARY The diagnosis and treatment of ectopic pregnancy has markedly evolved over the past several decades. With improved pregnancy tests and ultrasonography, the diagnosis of ectopic pregnancy can usually be made early, before tubal rupture. Diagnostic algorithms may aid the clinician in making the correct diagnosis and managing the patient. Prompt diagnosis allows for more therapeutic options, including conservative surgical approaches and medical management. These methods continue to be evaluated in research studies, adding to the clinician’s ability to base treatment decisions on evidence-based medical practices. Ongoing studies are focusing on novel diagnostic modalities, using biochemical as well as genomic approaches, while attempting to better understand the molecular mechanisms that allow for ectopic implantation.
PEARLS ●
●
●
●
● ●
Important risk factors for ectopic pregnancy include prior tubal surgery, ectopic pregnancy, or history of PID. The relationship between serum hCG levels and ultrasonography is critical for determining the potential for ectopic pregnancy. Methotrexate is the treatment of choice in stable patients without medical contraindications. Surgery should be considered if patients desire sterilization or in cases of previous ectopic pregnancies in the same tube. Salpingostomy is the surgical treatment of choice. Salpingectomy should be considered if the tube is severely damaged, it is a recurrent ectopic pregnancy in the same tube, or in the case of uterine rupture or uncontrolled bleeding or large ectopic pregnancies.
REFERENCES
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1. Centers for Disease Control and Prevention: Ectopic pregnancy— United States, 1990–1992. MMWR 44:46–48, 1995. 2. Fylstra DL: Tubal pregnancy: A review of current diagnosis and treatment. Obstet Gynecol Surv 53:320–328, 1998. 3. Barnhart K, Esposito M, Coutifaris C: An update on the medical treatment of ectopic pregnancy. Obstet Gynecol Clin North Am 27:653–667, 2000. 4. Pisarska MD, Carson SA, Buster JE: Ectopic pregnancy. Lancet 351:1115–1120, 1998. 5. Washington AE, Katz P: Ectopic pregnancy in the United States: Economic consequences and payment source trends. Obstet Gynecol 81:287–292, 1993.
6. Bouyer J, Coste J, Fernandez H, et al: Sites of ectopic pregnancy: A 10-year population-based study of 1800 cases. Hum Reprod 17:3224–3230, 2002. 7. Gun M, Mavrogiorgis M: Cervical ectopic pregnancy: A case report and literature review. Ultrasound Obstet Gynecol 19:297–301, 2002. 8. Parente JT, Ou CS, Levy J, Legatt E: Cervical pregnancy analysis: A review and report of five cases. Obstet Gynecol 62:79–82, 1983. 9. Hunter RHF: Tubal ectopic pregnancy: A patho-physiological explanation involving endometriosis. Hum Reprod 17:1688–1691, 2002. 10. Goddijn M, van der Veen F, Schuring-Blom GH, et al: Cytogenetic characteristics of ectopic pregnancy. Hum Reprod 11:2769–2771, 1996.
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Chapter 48 Ectopic Pregnancy 11. Coste J, Fernandez H, Joye N, et al: Role of chromosome abnormalities in ectopic pregnancy. Fertil Steril 2000;74:1259–1260. 12. Ankum W, Mol B, Van de Veen F, Bossuyt P: Risk factors for ectopic pregnancy: A meta-analysis. Fertil Steril 65:1093–1099, 1996. 13. Della-Giustina D, Denny M: Ectopic pregnancy. Emerg Med Clin North Am 21:565–584, 2003. 14. Yao M, Tulandi T: Current status of surgical and nonsurgical management of ectopic pregnancy. Fertil Steril 67:421–433, 1997. 15. Maymon R, Shulman A: Controversies and problems in the current management of tubal pregnancy. Hum Reprod Update 2:541–551, 1996. 16. DeVoe RW, Pratt JH: Simultaneous intrauterine and extrauterine pregnancy. Am J Obstet Gynecol 56:1119, 1948. 17. Dart RD, Kaplan B, Vavaklis K: Predictive value of history and physical examination in patients with suspected ectopic pregnancy. Ann Emerg Med 33:283–290, 1999. 18. Richards SR, Stempel LS, Carlton BD: Heterotopic pregnancy. Reappraisal of incidence. Am J Obstet Gynecol 142:928–930, 1982. 19. Goldman GA, Fisch B, Ovadia J, Tadir Y: Heterotopic pregnancy after reproductive technologies. Obstet Gynecol Surv 47:217–221, 1992. 20. Saxon D, Falcone T, Mascha EJ, et al: A study of ruptured tubal ectopic pregnancy. Obstet Gynecol 90:46–49, 1997. 21. Bickell NA, Bodian C, Anderson RM, Kase N: Time and the risk of ruptured tubal pregnancy. Obstet Gynecol 104:789–794, 2004. 22. Tulandi T, Hemmings R, Khalifa F: Rupture of ectopic pregnancy in women with low and declining serum β-human chorionic gonadotropin concentrations. Fertil Steril 56:786–787, 1991. 23. Irvine LM, Padwick ML: Serial serum hCG measurements in a patient with an ectopic pregnancy: A case for caution. Hum Reprod 15:1646–1647, 2000. 24. Goldstein SR, Snyder JR, Watson C, Danon M: Very early pregnancy detection with endovaginal ultrasound. Obstet Gynecol 72:200–204, 1988. 25. Condous G, Okaro E, Khalid A, et al: The accuracy of transvaginal ultrasonography for the diagnosis of ectopic pregnancy prior to surgery. Hum Reprod 20:1404–1409, 2005. 26. Barnhart K, Mennuti MT, Benjamin I, et al: Prompt diagnosis of ectopic pregnancy in an emergency department setting. Obstet Gynecol l84:1010–1015, 1994. 27. Kadar N, Caldwell BV, Romero R: A method of screening for ectopic pregnancy and its indications. Obstet Gynecol 52:162–166, 1981. 28. Kadar N, Romero R: Observations on the log human chorionic gonadotropin-time relationship in early pregnancy and its practical implications. Am J Obstet Gynecol 157:73–78, 1987. 29. Romero R, Kadar N, Copel JA, et al: The value of serial human chorionic gonadotropin testing as a diagnostic tool in ectopic pregnancy. Am J Obstet Gynecol 155:392–394, 1986. 30. Pittaway DE, Wentz AC: Evaluation of early pregnancy by serial chorionic gonadotropin determinations: A comparison of methods by receiver operating characteristic curve analysis. Fertil Steril 43:529–533, 1985. 31. Kadar N, Freedman M, Zacher M: Further observation on the doubling time of hCG in early asymptomatic pregnancy. Fertil Steril 54:783–787, 1990. 32. Fritz M, Guo S: Doubling time of hCG in early normal pregnancy: Relationship to hCG concentration and gestational age. Fertil Steril 47: 584–589, 1987. 33. Lenton EA, Neal LM, Sulaiman R: Plasma concentrations of human chorionic gonadotropin from the time of implantation until the second week of pregnancy. Fertil Steril 37:773–778, 1982. 34. Barnhart K, Sammel MD, Rinaudo PF, et al: Symptomatic patients with an early intrauterine pregnancy: hCG curves redefined. Obstet Gynecol 104:50–55, 2004. 35. Spandorfer SD, Menzin AW, Barnhart KT, et al: Gynecology: Efficacy of frozen-section evaluation of uterine curettings in the diagnosis of ectopic pregnancy. Am J Obstet Gynecol 175:603–605, 1996. 36. Lindahl B, Ahlgren M: Identification of chorionic villi in abortion specimens. Obstet Gynecol 67:79–81, 1986.
37. Kristiansen JD, Clausen I, Nielsen MN, Thomsen SG: Stereomicroscopic demonstration of chorionic villi: Differentiation between miscarriage and ectopic pregnancy. BJOG 100:839–841, 1993. 38. Barnhart KT, Gracia CR, Reindl B, Wheeler JE: Usefulness of Pipelle endometrial biopsy in the diagnosis of women at risk for ectopic pregnancy. Am J Obstet Gynecol 188:906–909, 2003. 39. Ries A, Singson P, Bidus M, Barnes JG: Use of the endometrial Pipelle in the diagnosis of early abnormal gestations. Fertil Steril 74:593–595, 2000. 40. Mol BW, Lijmer JG, Ankum WM, et al: The accuracy of single serum progesterone measurement in the diagnosis of ectopic pregnancy: A meta-analysis. Hum Reprod 13:3220–3227, 1998. 41. McCord ML, Muran D, Buster J, et al: Single serum progesterone as a screen for ectopic pregnancy: Exchanging specificity and sensitivity to obtain optimal test performance. Fertil Steril 66:513–516, 1996. 42. Buckley RG, King KJ, Riffernburgh RH, et al: Serum progesterone testing to predict ectopic pregnancy in symptomatic first-trimester patients. Ann Emerg Med 36:95–100, 2000. 43. Ness RB, McLaughlin MT, Heine RP, et al: Fetal fibronectin as a marker to discriminate between ectopic and intrauterine pregnancies. Am J Obstet Gynecol 179:697–702, 1998. 44. Vitoratos N, Gregoriou O, Papadias C, et al: Clinical value of creatinine kinase in the diagnosis of ectopic pregnancy. Gynecol Obstet Invest 46:80–83, 1998. 45. Daniel Y, Geva E, Lerner-Geva L, et al: Levels of vascular endothelial growth factor are elevated in patients with ectopic pregnancy: Is this a novel marker? Fertil Steril 72:1013–1017, 1999. 46. Predanic M: Differentiating tubal abortion from viable ectopic pregnancy with serum CA-125 and beta-human chorionic gonadotropin determinations. Fertil Steril 73:522–525, 2000. 47. Saha PK, Gupta I, Ganguly NK: Evaluation of serum creatine kinase as a diagnostic marker for tubal pregnancy. Austral NZ J Obstet Gynecol 39:366–367, 1999. 48. Felemban A, Sammour A, Tulandi T: Serum vascular endothelial growth factor as a possible marker for early ectopic pregnancy. Hum Reprod 17:490–492, 2002. 49. Fasouliotis SJ, Spandorfer SD, Witkin SS, et al: Maternal serum vascular endothelial growth factor levels in early ectopic and intrauterine pregnancies after in vitro fertilization treatment. Fertil Steril 82:309–313, 2004. 50. Gerton GL, Fan XJ, Chittams J, et al: A serum proteomics approach to the diagnosis of ectopic pregnancy. Ann NY Acad Sci 1022:306–312, 2004. 51. Gracia CR, Barnhart KT: Diagnosing ectopic pregnancy: A decision analysis comparing six strategies. Obstet Gynecol 97:464–470, 2001. 52. Barnhart K, Sammel MD, Chung K, et al: Decline of serum hCG and spontaneous complete abortion: Defining the normal curve. Obstet Gynecol 104:975–981, 2004. 53. Barnhart K, Spandorfer S, Coutifaris C: Medical treatment of interstitial pregnancy: A report of three unsuccessful cases. J Reprod Med 42:521–524, 1997. 54. Barnhart KT, Simhan H, Kamelle S: Diagnostic accuracy of ultrasound above and below the beta-hCG discriminatory zone. Obstet Gynecol 94:583–587, 1999. 55. Mol BW, Hajenius PJ, Ankum WM, et al: Screening for ectopic pregnancy in symptom-free women at increased risk. Obstet Gynecol 89:704–707, 1997. 56. Mol BW, van der Veen F, Bossuyt PM: Symptom-free women at increased risk of ectopic pregnancy: Should we screen? Acta Obstet Gynecol Scand 81:661–672, 2002. 57. Vermesh M, Silva PD, Rosen GF, et al: Management of unruptured ectopic gestation by linear salpingostomy: A prospective, randomized clinical trial of laparoscopy versus laparotomy. Obstet Gynecol 73:400–404, 1989. 58. Lundorff P, Thorburn J, Lindblom B: Fertility outcome after conservative surgical treatment of ectopic pregnancy evaluated in a randomized trial. Fertil Steril 57:998–1002, 1992.
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59. Murphy AA, Nager CW, Wujek JJ, et al: Operative laparoscopy versus laparotomy for the management of ectopic pregnancy: A prospective trial. Fertil Steril 57:1180–1185, 1992. 60. Hajenius PJ, Mol BWJ, Bossuyt PMM, et al: Interventions for tubal ectopic pregnancy. Cochrane Database Syst Rev 2003 3:CD000324. 61. Damario MA, Rock JA: Ectopic pregnancy. In Rock JA, Jones HW (eds). TeLinde’s Operative Gynecology, 9th ed. Philadelphia, Lippincott Williams & Wilkins, 2003, pp 507–536. 62. Ory SJ: Ectopic pregnancy. In Endoscopic Management of Gynecologic Disease. Adamson GD, Martin DC (eds). Philadelphia, LippincottRaven Publishers, 1996, pp. 97–108. 63. Balasch J, Barri PN: Treatment of ectopic pregnancy: The new gynaecological dilemma. Hum Reprod 9:547–548, 1994. 64. McComb P, Gomel V: Linear ampullary salpingotomy heals better by secondary versus primary closure. Fertil Steril 41:454, 1984. 65. Tulandi T, Guralnick M: Treatment of tubal ectopic pregnancy by salpingotomy with or without tubal suturing and salpingectomy. Fertil Steril 56:374–375, 1991. 66. Fujishita A, Masuzaki H, Newaz Khan K, et al: Laparoscopic salpingotomy for tubal pregnancy: Comparison of linear salpingotomy with and without suturing. Hum Reprod 19:1195–1200, 2004. 67. DiMarchi JM, Kosasa TS, Kobara TX, Hace RW: Persistent ectopic pregnancy. Obstet Gynecol 70:555–560, 1987. 68. Vermesh M, Silva PD, Sauer MV, et al: Persistent tubal ectopic gestation: Patterns of circulation of beta-human chorionic gonadotropin and progesterone, and management options. Fertil Steril 50:584–590, 1988. 69. Seifer DB, Gutman JN, Grant WD, et al: Comparison of persistent ectopic pregnancy after laparoscopic salpingostomy versus salpingostomy at laparotomy for ectopic pregnancy. Obstet Gynecol 81:378–382, 1993. 70. Spandorfer SD, Sawin SW, Benjamin I, Barnhart KT: Postoperative day 1 serum human chorionic gonadotropin level as a predictor of persistent ectopic pregnancy after conservative surgical management. Fertil Steril 68:430–434, 1197. 71. Graczykowski JW, Mishell DR: Methotrexate prophylaxis of persistent ectopic pregnancy after conservative treatment by salpingostomy. Obstet Gynecol 89:118–122, 1997. 72. Gracia CR, Brown HA, Barnhart KT: Prophylactic methotrexate after linear salpingostomy: A decision analysis. Fertil Steril 76:1191–1195, 2001. 73. Barnhart K, Coutifaris C, Esposito M: The pharmacology of methotrexate. Expert Opin Pharm 2:409–417, 2001. 74. Calabresi P, Chabner B: Antineoplastic agents. In Gilman A, Goodman LS, Goodman A (eds). The Pharmacologic Basis of Therapeutics, 8th ed. New York, Macmillan, 2005, pp. 1275–1276. 75. Barnhart K, Katz I, Hummel A, Gracia CG: Presumed diagnosis of ectopic pregnancy. Obstet Gynecol 100:505–510, 2002. 76. Ailawadi M, Lorch SA, Barnhart KT: Cost effectiveness of presumptively medically treating women at risk for ectopic pregnancy compared to first performing a D&C. Fertil Steril 83:376–382, 2005. 77. American College of Obstetricians and Gynecologists: Medical Management of Tubal Pregnancy. Washington, DC, ACOG Practice Bulletin no. 3, 1998. 78. Glock JL, Johnson JV, Brumsted JR: Efficacy and safety of single-dose systemic methotrexate in the treatment of ectopic pregnancy. Fertil Steril 62:716–721, 1994. 79. Stovall TG, Ling FW: Single dose methotrexate: An expanded clinical trial. Am J Obstet Gynecol 168:1759–1765, 1993. 80. Lipscomb GH, Meyer NL, Flynn DE, et al: Oral methotrexate for treatment of ectopic pregnancy. Am J Obstet Gynecol 186:1192–1195, 2002. 81. Stovall TG, Ling FW, Buster JE: Outpatient chemotherapy of unruptured ectopic pregnancy. Fertil Steril 51:435–438, 1989 . 82. Stovall TG, Ling FW, Gray LA: Single-dose methotrexate for treatment of ectopic pregnancy. Obstet Gynecol 77:754–757, 1991. 83. Lipscomb GH, Bran D, McCord ML, et al: Analysis of 315 ectopic pregnancies treated with single-dose methotrexate. Am J Obstet Gynecol 178:1354–1358, 1998.
84. Trout S, Kemmann E: Reversible alopecia after single-dose methotrexate treatment in a patient with ectopic pregnancy. Fertil Steril 64:866–867, 1995. 85. Straka M, Zeringue E, Goldman M: A rare drug reaction to methotrexate after treatment for ectopic pregnancy. Obstet Gynecol 103:1047–1048, 2004. 86. Barnhart KT, Gosman G, Ashby R, Sammel M: The medical management of ectopic pregnancy: A meta-analysis comparing “single dose” and “multidose” regimens. Obstet Gynecol 101:778–784, 2003. 87. Lipscomb GH, McCord ML, Stovall TG, et al: Predictors of success of methotrexate treatment in women with tubal ectopic pregnancies. NEJM 341:1974–1978, 2000. 88. Lipscomb GH, Puckett KJ, Bran D, Ling FW: Management of separation pain after single-dose methotrexate therapy for ectopic pregnancy. Obstet Gynecol 93:590–593, 1999. 89. Thompson GR, O’Shea RT, Harding A: Beta-HCG levels after conservative treatment of ectopic pregnancy: Is a plateau normal? Aust NZ J Obstet Gynecol 34:96–99, 1994. 90. Elito J, Reichmann AP, Uchiyama MN, Camano L: Predictive score for the systemic treatment of unruptured ectopic pregnancy with a single dose of methotrexate. Int J Gynecol Obstet 67:75–79, 1999. 91. Tawfiq A, Agameya A-F, Claman P: Predictors of treatment failure for ectopic pregnancy treated with single-dose methotrexate. Fertil Steril 74:877–880, 2000. 92. Potter MB, Lepine LA, Jamieson DJ: Predictors of success with methotrexate treatment of tubal ectopic pregnancy at Grady Memorial Hospital. Am J Obstet Gynecol 188:1192–1194, 2003. 93. Hajenius PJ, Engelsbel S, Mol BWJ, et al: Randomized trial of systemic methotrexate versus laparoscopic salpingostomy in tubal pregnancy. Lancet 350:774–779, 1997. 94. Saraj AJ, Wilcox JG, Najmabadi S, et al: Resolution of hormonal markers of ectopic gestation: A randomized trial comparing singledose intramuscular methotrexate with salpingostomy. Obstet Gynecol 92:989–994, 1998. 95. Sowter MC, Farquhar CM, Petrie KJ, Gudex G: A randomized trial comparing single dose systemic methotrexate and laparoscopic surgery for the treatment of unruptured tubal pregnancy. BJOG 108:192–203, 2001. 96. Lewis-Bliehall C, Rogers RC, Kammerer-Doak DN, et al: Medical vs. surgical treatment of ectopic pregnancy. J Reprod Med 46:983–988, 2001. 97. Feichtinger W, Kemeter P: Conservative treatment of ectopic pregnancy by transvaginal aspiration under sonographic control and injection of methotrexate. Lancet 1:381–382, 1987. 98. Pansky M, Bukovsky I, Golan A: Local methotrexate injection: A nonsurgical treatment of ectopic pregnancy. Am J Obstet Gynecol 161:393–396, 1989. 99. Risquez F, Mathieson J, Pariente D, et al: Diagnosis and treatment of ectopic pregnancy by retrograde selective salpingography and intraluminal methotrexate injection. Hum Reprod 5:759–762, 1990. 100. Goldenberg M, Bider D, Oelsner G, et al: Treatment of interstitial pregnancy with methotrexate via hysteroscopy. Fertil Steril 58:1234–1236, 1992. 101. Robertson DE, Smith W, Moye MA, et al: Reduction of ectopic pregnancy by injection under ultrasound control. Lancet 1:974–975, 1987. 102. Timor-Tritsch I, Baxi L, Peisner DB: Transvaginal salpingocentesis: A new technique for treating ectopic pregnancy. Am J Obstet Gynecol 160:459–460, 1989. 103. Pansky M, Golan A, Bukovsky I, Caspi E: Nonsurgical management of tubal pregnancy: Necessity in view of the changing clinical appearance. Am J Obstet Gynecol 164:888–895, 1991. 104. Yeko TR, Mayer JC, Parsons AK, Maroulis GB: A prospective series of unruptured ectopic pregnancies treated by tubal injection with hyperosmolar glucose. Obstet Gynecol 85:265–268, 1995. 105. Laatikainen L, Tuomivara L, Kaar K: Comparison of local injection of hyperosmolar glucose solution with salpingostomy for the conservative treatment of tubal pregnancy. Fertil Steril 60:80–84, 1993. 106. Lund JJ: Early ectopic pregnancy. J Obstet Gynaecol Br Empire 62:70–75, 1955.
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Chapter 48 Ectopic Pregnancy 107. Trio D, Strobelt N, Picciolo C, et al: Prognostic factors for successful expectant management of ectopic pregnancy. Fertil Steril 63:469–472, 1995. 108. Korhonen J, Stenman UH, Ylostalo P: Serum chorionic gonadotropin dynamics during spontaneous resolution of ectopic pregnancy. Fertil Steril 61:632–636, 1994. 109. Barnhart KT, Rinaudo P, Hummel A, et al: Acute and chronic presentation of ectopic pregnancy may be two clinical entities. Fertil Steril 80:1344–1351, 2003. 110. Lau S, Tulandi T: Conservative medical and surgical management of interstitial ectopic pregnancy. Fertil Steril 72:207–215, 1999. 111. Jafri SZ, Loginsky SJ, Bouffard JA, Selis JE: Sonographic detection of interstitial pregnancy. J Clin Ultrasound 15:253–257, 1987. 112. Timor-Tritsch IE, Monteagudo A, Matera C, Veit CR: Sonographic evolution of cornual pregnancies treated without surgery. Obstet Gynecol 79:1044–1049, 1992. 113. Grobman WA, Milad MP: Conservative laparoscopic management of a large cornual ectopic pregnancy. Hum Reprod 13:2002–2004, 1998. 114. Sanz LE, Verosko J: Hysteroscopic management of cornual ectopic pregnancy. Obstet Gynecol 99:941–944, 2002. 115. Rodriguez L, Takacs P, Kang L: Single-dose methotrexate for the management of interstitial ectopic pregnancy. Intl J Gynecol Obstet 84:271–272, 2004. 116. Gaudoin MR, Coulter KL, Robins AM, et al: Is the incidence of ovarian ectopic pregnancy increasing? Eur J Obstet Gynecol 70:141–143, 1996. 117. Hage PS, Arnouk IF, Zarou DM, et al: Laparoscopic management of ovarian ectopic pregnancy. J Amican Assoc Gynecol Laparosc 1:283–285, 1994. 118. Chelmow D, Gates E, Penzias AS: Laparoscopic diagnosis and methotrexate treatment of an ovarian pregnancy: A case report. Fertil Steril 62:879–881, 1994. 119. Ginath S, Malinger G, Golan A, et al: Successful laparoscopic treatment of a ruptured primary abdominal pregnancy. Fertil Steril 74:601–602, 2000. 120. Mitra A, LeQuire MH: Minimally invasive management of 14.5-week abdominal pregnancy without laparotomy. J Ultrasound Med 22:709–714, 2003. 121. Gerli S, Rossetti D, Baiocchi G, et al: Early ultrasonographic diagnosis and laparoscopic treatment of abdominal pregnancy. Eur J Obstet Gynecol 113:103–105, 2004. 122. Rahaman J, Berkowitz R, Mitty H, et al: Minimally invasive management of an advanced abdominal pregnancy. Obstet Gynecol 103:1064–1068, 2004. 123. Yao M, Tulandi T: Surgical and medical management of tubal and nontubal ectopic pregnancies. Curr Opin Obstet Gynecol 10:371–374, 1998.
124. Ash S, Farrell S: Hysteroscopic resection of a cervical ectopic pregnancy. Fertil Steril 66:842–844, 1996. 125. Ushakov FB, Elchalal U, Aceman PJ, Schenker JG: Cervical pregnancy: Past and future. Obstet Gynecol Surv 52:45–59, 1996. 126. Mitra AG, Harris-Owens M: Conservative medical management of advanced cervical ectopic pregnancies. Obstet Gynecol Surv 55:385–389, 2000. 127. Cepni I, Ocal P, Erkan S, Erzik B: Conservative treatment of cervical ectopic pregnancy with transvaginal ultrasound-guided aspiration and single-dose methotrexate. Fertil Steril 81:1130–1132, 2004. 128. Hallatt J: Repeat ectopic pregnancy: A study of 123 consecutive cases. Am J Obstet Gynecol 45:542–546, 1975. 129. Schoen JA, Nowak RJ: Repeat ectopic pregnancy: A 16-year clinical survey. Obstet Gynecol 45:542–546, 1975. 130. Paavonen J, Varjonen-Toivonen M, Komulainen M, Heinonen PK: Diagnosis and management of tubal pregnancy: Effect on fertility outcome. Int J Gynaecol Obstet 23:129–133, 1985. 131. Sandevei R, Bergsjo P, Ulstein M, Steier JA: Repeat ectopic pregnancy: A 20-year hospital survey. Acta Obstet Gynecol Scand 6:635–640, 1987. 132. Skjeldestad FE, Hadgu A, Eriksson N: Epidemiology of repeat ectopic pregnancy: A population-based prospective cohort study. Obstet Gynecol 91:129–135, 1998. 133. Butts S, Sammel M, Hummel A, et al: Risk factors and clinical features of recurrent ectopic pregnancy: A case control study. Fertil Steril 80:1340–1344, 2003. 134. Ego A, Subtil D, Cosson M, et al: Survival analysis of fertility after ectopic pregnancy. Fertil Steril 75:560–566, 2001. 135. Tulandi T. Reproductive performance of women after two tubal ectopic pregnancies. Fertil Steril 50:164–166, 1998. 136. Korell M, Albrich W, Hepp H: Fertility after organ-reserving surgery of ectopic pregnancy: Results of a multicenter study. Fertil Steril 68:220–223, 1997. 137. Bangsgaard N, Lund CO, Ottesen B, Nilas L: Improved fertility following conservative surgical treatment of ectopic pregnancy. BJOG 110:765–770, 2003. 138. Vermesh M, Presser SC: Reproductive outcome after linear salpingostomy for ectopic pregnancy: A prospective 3-year follow-up. Fertil Steril 57:682–684, 1992. 139. Dias Pereira G, Hajenius PJ, Mol BWJ, et al: Fertility outcome after systemic methotrexate and laparoscopic salpingostomy for tubal pregnancy. Lancet 353:724–725, 1999. 140. Fernandez H, Yves Vincent SCA, Pauthier S, et al: Randomized trial of conservative laparoscopic treatment and methotrexate administration in ectopic pregnancy and subsequent fertility. Hum Reprod 13:3239–3242, 1998.
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Endometriosis Robert Hemmings and Tommaso Falcone
INTRODUCTION Endometriosis is a complex disease that is responsible for a significant number of hospital admissions and operative procedures. This disease typically manifests itself as a chronic disorder, with pain and infertility as the primary symptoms. The prevalence of endometriosis in the general population is unknown and will remain so until a reliable, noninvasive test can be applied to a large unselected population. Because the standard method of diagnosing endometriosis is an invasive surgical procedure, any studied population will be symptomatic and will represent a biased segment of the overall population. Within these symptomatic populations, the reported prevalence has been increasing over the past two decades. This is likely due to the recognition of more subtle forms of endometriosis and the more liberal use of diagnostic laparoscopy.1 This observed increased prevalence might also represent a real increase in the incidence of endometriosis due to sociological, environmental, and genetic factors.
TYPES OF ENDOMETRIOSIS The microscopic definition of endometriosis implies the presence of endometrial glands and stroma outside the endometrial cavity and uterine musculature. After the introduction of laparoscopy in the late 1960s, black puckered peritoneal lesions were the first lesions to be recognized as representing endometriosis. In the mid-1980s, we recognized that different forms of nonpigmented lesions also contained the required histologic features of endometriosis. Deep infiltrating endometriosis2,3 is recognized as a separate clinical entity that might be easily missed at laparoscopy and may have a different etiology than the classic peritoneal and ovarian lesions. Lesions can appear red, white, or brown/black. The classically recognized lesions of endometriosis take the form of black puckered lesions and are generally located on the peritoneal surface of pelvic organs. Histologically, the brown or black appearance is the result of hemosiderin deposition in the macrophage after repetitive bleeding. Other important histologic features of these lesions include fibrin deposition secondary to inflammatory reactions, neovascularization resulting from the production of angiogenic factors, and fibrosis. The clinical appearance at laparoscopy is the result of a combination of all these factors. Typical brown/black lesions are now believed to be the end result of subtle lesions that have evolved over a number of years.4 New lesions appear red and then turn white as they shed and grow, and they ultimately turn black as a result of both the
hemosiderin deposition and intraluminal debris. This theory of lesion evolution is supported by the average age at which these lesions are found in patients. The red lesions are found mainly in younger patients; the black and white lesions are generally observed in older patients.5 The black lesions may be of different dimension and depth of penetration than the red and white lesions. The red lesions are the most metabolically active, whereas the white lesions are the least active.
Ovarian Endometriosis Ovarian endometriosis, or endometriomas, increase with age and are generally associated with a more advanced stage of the disease.6 This form of endometriosis can be diagnosed with a high level of accuracy by serial ultrasounds.7 The main differential diagnosis is a hemorrhagic corpus luteum, which will disappear over the course of a few months. These ovarian forms of endometriosis often have associated peritoneal implants, although only a small percentage of patients with peritoneal implants will eventually develop an endometrioma. Endometriomas can be uniloculated or multiloculated. They are more commonly localized in the left ovary8 because peritoneal implants are more common in the left hemipelvis.
Deep Endometriosis Invasion of endometriosis deeper than 5 mm has been associated with increased pain.9 These lesions have been grouped with the following classification: large area surrounded by sclerotic white lesions (Type I), area of retraction of the bowel (Type II), a nodule of the rectovaginal septum (Type III), and sclerosing endometriosis invading the sigmoid colon (Type IV). These lesions can be difficult to classify during laparoscopy due to the retroperitoneal nature of the disease. A rectovaginal examination during the menstrual period in the office setting or a thorough examination under anesthesia before laparoscopy may alert the surgeon to the presence of these types of lesions.
PREVALENCE OF ENDOMETRIOSIS Over the past three decades, the incidence of endometriosis in patients who present with either pelvic pain or infertility has been increasing and has been reported to be as high as 80%.10 This increase has been proportional to the surgeon’s awareness of subtle lesions and deep endometriosis. If microscopic endometriosis is included, virtually all women with pelvic pain or infertility have some form of endometriosis. The classic lesions generally appear later in life and will have an incidence as high as 70% in patients with pelvic pain or infertility.11
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Section 7 Reproductive Surgery The incidence of ovarian cystic endometriosis (endometriomas) increases with age,6 but its incidence and progression seem to stabilize in patients who are older than age 35. The prevalence of endometriosis in the general population is estimated to range from 1% to 3%. Approximately 10% to 20% of patients undergoing laparoscopy for pelvic pain or infertility are found to have deep endometriosis.6
CLASSIFICATION OF ENDOMETRIOSIS The classification of endometriosis has been an evolving process. The first classification system to gain widespread acceptance was that of Acosta and colleagues in 1973,12 which classified endometriosis as mild, moderate, or severe and showed an inverse relationship to pregnancy rates. In 1978, the American Fertility Society (AFS, now called the American Society for Reproductive Medicine [ASRM]) convened a committee to design a classification system, which was published in 1979.13 This classification included four stages and used a weighted pain score that included assessment of the extent of endometriosis in two dimensions and the presence and extent of adhesions in the peritoneum, ovaries, and tubes. It also took into account whether the endometriosis was unilateral or bilateral. The size of the endometrioma was also taken into account, along with the presence of filmy versus dense adhesions. In 1985,14 the original AFS classification was revised because of its inability to predict pregnancy. It now includes a threedimensional assessment of the disease differentiating superficial from invasive disease (Figs. 49-1 and 49-2). It also quantifies the extent of adhesion around the tubes and ovaries and distinguishes between incomplete and complete enclosure of the fimbria, the latter of which automatically places the disease in the moderate category. Cul-de-sac adhesions are weighted heavily, with complete obliteration, which is characteristic of severe disease, resulting in a stage IV assignment. An endometrioma that is larger than 3 cm in diameter is at least stage III disease. In 1996,15 a further revision was introduced in the AFS classification (ASRM) in an attempt to correlate the results with pain. This included a description and photography of the lesions. The lesions are categorized as red (red, red-pink, clear, white, yellowbrown, and peritoneal defects) and black (blue and black) (Figs. 49-3 and 49-4). The percentage of each of these lesions is also documented. Despite these improvements, the correlation between the stage of endometriosis and the likelihood of pregnancy is poor, and future improvement in the classification is likely.16 Another limitation of the ASRM classification stems from the fact that this system was mainly designed to assess a patient’s fertility potential and correlates poorly with the pain level. Many authors17 have found no correlation between the degree of pain and the ASRM classification system. However, a correlation between pain and the depth of penetration (5 mm or more) does seem to exist.9
with low estrogen levels, smokers, and women who exercise intensely appear to be at decreased risk. There is a correlation between the volume of menstrual flow and the prevalence of endometriosis. This may lead to an increase in menstrual tubal reflux. Clinical conditions that are associated with an increase in menstrual reflux—a noncommunicating uterine horn, for example—are associated with a virtually 100% incidence of endometriosis.2 Increased exposure to menstrual flow, which occurs with early menarche and nulliparity, has been correlated with a high incidence of the disease.18 In a recent study of 2777 women with endometriosis,19 the authors reported that the proportion of patients who had a uterine fibroid was significantly higher than those without fibroids. This finding suggests a causal relationship between endometriosis and the presence of uterine fibroids, which might be due to an increased menstrual flow reflux in these patients. There appears to be some correlation between a higher degree of education, social stress, and the prevalence of disease.19 The Nurses’ Health Study prospectively assessed predisposing factors for endometriosis and observed an association with early age of menarche, shorter length of menstrual cycles during late adolescence, and nulliparity. In parous women, a decreased risk was found with the number of liveborn children and duration of
PREDISPOSING FACTORS FOR ENDOMETRIOSIS
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Endometriosis is mainly present during the reproductive years and regresses during menopause, suggesting that the growth of endometriosis is estrogen-dependent. Furthermore, women
Figure 49-1
ASRM revised classification of endometriosis.
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Chapter 49 Endometriosis Figure 49-2 (ASRM).
Examples of scoring
Figure 49-3 Typical black and white lesions of the pelvic peritoneum with dense fibrosis and retraction.
Figure 49-4
lactation.20 In the best animal model for endometriosis, the stress of captivity was associated with a higher incidence of endometriosis.21 Heredity is an important predisposing factor for endometriosis because the prevalence is increased sevenfold among first-degree relatives. In monozygotic twins, the prevalence increased 15-fold.22 Exposure to pollutants, especially endocrine-disrupting compounds such as dioxins or polychlorinated biphenyls, might also play a role in the predisposition to endometriosis. In the baboon, for instance, exposure to increasing amounts of dioxin correlated with the incidence and extent of endometriosis.23 In
vitro data has also shown that these dioxins affect the expression of stromal progesterone receptor expression.24 Some human data also support a role for these toxins in the pathophysiology of endometriosis.25 There is a correlation between infertility, pelvic pain, dysmenorrhea, dyspareunia, and endometriosis. Although stage I endometriosis may not be more common in infertile women than in fertile women, stage II is significantly more common in infertile patients.26 Although some authors have found a correlation between alcohol use and endometriosis, others have not been able to
Typical red lesion on the right uterosacral ligament.
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Section 7 Reproductive Surgery confirm these results. The use of oral contraception has been linked to an increased risk27 of endometriosis, but other studies either found a protective effect28 or no correlation at all.19 The use of an intrauterine contraceptive device is not associated with increased incidence of endometriosis.19 Body mass index has not been correlated with the incidence of endometriosis. It is unknown whether diet and exercise can halt or limit the evolution of endometriosis. Early exposure to pregnancy may help protect against endometriosis. Indeed, symptoms associated with endometriosis such as pelvic pain are often decreased for a number of years after pregnancy. The difficulty with assessing risk is often due to the common presence of endometriosis in the pelvis that may not be pathologic. Based on a study that involved repetitive laparoscopy in baboons, we know that endometriosis appears spontaneously29 and that new lesions seem to appear and disappear spontaneously. Thus, endometriotic lesions in humans most likely are in continuous evolution as well.
refluxed through the fallopian tubes at the time of menstruation; second, these cells must be viable; and third, they should implant anatomically based on the distribution of reflux cells in the peritoneal cavity. Numerous studies and frequent clinical observations made during endoscopies confirm that blood frequently refluxes through the fallopian tubes around the time of menstruation. In fact, it has been observed that higher volumes of refluxed blood and endometrial tissue fragments are found at the time of menstruation in patients with endometriosis. This may be due to hypotonicity of the uterotubal junction or an increased resistance of the cervix to the expulsion of menstrual flow in the vagina. The viability of exfoliated endometrial cells has been proven by the culture of menstrual fluid or peritoneal fluid containing such endometrial cells. An intact peritoneal surface does not act as a barrier to endometriosis formation.30 However, certain conditions need to be present for endometrial tissue to invade and persist. Recent
PATHOPHYSIOLOGY The classical theories of endometriosis are the transplantation, coelomic metaplasia, induction, and vascular/lymphatic dissemination theories. The transplantation theory proposes that endometrium regurgitated into the peritoneal cavity implants on the peritoneum. The induction theory is similar, except it holds that the endometrium or perhaps another agent induces metaplasia of the mesothelium to endometriotic tissue. The coelomic metaplasia theory proposes that undifferentiated cells of müllerian origin in the peritoneal cavity can differentiate to endometrial tissue. The theory of vascular spread can explain the presence of endometriosis at distant sites.
Transplantation Theory The basic components of the disease process are an abnormal endometrium, invasion of the peritoneum, angiogenesis, and an immune response and inflammation (Table 49-1; Fig. 49-5). The most accepted general concept of the etiology of this disease is the transplantation theory of Sampson. In 1927, Sampson proposed that endometrial cells regurgitated through the fallopian tubes and implanted on different peritoneal surfaces, leading to endometriosis. However, three major elements must be present to support the Sampson theory: first, endometrial cells must be
Endometrial tissue
Table 49-1 Important Components for Implantation of Endometrium Abnormal endometrium Genes abnormally expressed
Macrophage
Mesothelium
Attachment and invasion of the peritoneum Altered expression of MMP Haptoglobin Neoangiogenesis VEGF Inflammation Macrophage Decreased phagocytic capacity Cytokines and growth factors
732
MMP = matrix metalloproteinases; VEGF = vascular endothelial growth factor
Endometriotic implants
Figure 49-5 In patients with endometriosis there is a complex interaction between the eutopic endometrium, peritoneal macrophages, mesothelium, and the endometriotic implant. Patients who do not develop endometriosis are able to clear the regurgitated tissue. MCP-1, monocyte chemotactic protein-1.
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Chapter 49 Endometriosis data from the literature suggest that the endometrium of patients who are in the process of developing endometriosis is intrinsically different from that of patients without endometriosis.
Table 49-2 Impaired Peritoneal Environment Increased activated macrophages
Intrinsic Abnormalities of the Endometrium Apoptosis
Apoptosis plays a critical role in the normal function of the endometrium.31 This process helps eliminate senescent cells from the functional layer of the late secretory and menstrual endometrium. Apoptosis in the eutopic and ectopic endometrium is controlled by the Bcl-2 and Fas/FasL systems. The Bcl-2 system diminishes apoptosis, whereas the Fas/FasL system promotes apoptosis. These processes are altered in the endometrium of patients with endometriosis in a way that decreases apoptosis, leading possibly to an increase of viable regurgitated endometrial cells. Decreased Progesterone Sensitivity
The endometrium of patients with endometriosis shows a decreased sensitivity to progesterone. Numerous progesteroneresponsive genes may be abnormally expressed. Among these genes, those related to tissue remodeling are the most critical. Matrix metalloproteinases (MMPs) and their natural tissue inhibitors are enzymes that mediate normal tissue turnover, including the normal breakdown of the endometrium. Several MMPs are inappropriately expressed in the endometrium of patients with endometriosis during the luteal phase. Typically, MMPs are suppressed during this phase as a result of progesterone and other local factors. Continuous expression of MMPs is most likely associated with an altered response of the endometrium to progesterone in endometriosis patients. Matrix metalloproteinases promote tumor-cell invasion of tissues. Alterations in these enzymes are therefore likely to increase the invasive potential of refluxed endometrium.32,33 Furthermore, altered expression of these enzymes during the luteal phase may be associated with implantation disorders in patients with endometriosis. For endometrial cells to attach to the peritoneal surface, they must bind to the extracellular matrix (ECM). After attachment of endometrial cells to the peritoneal surface, endometrial glands must invade the peritoneal surface. This tissue degrades the ECM between the mesothelial cells, possibly via the persistent expression of MMP in refluxed endometrial tissue. MMP expression has been found in red lesions of endometriosis32 and endometriomas independent of the menstrual cycle phase. Type III procollagen—a byproduct of ECM metabolism—has been detected in the peritoneal fluid of patients with endometriosis.34
Angiogenic Factors Angiogenic factors may play a role in the survival of the implants. These angiogenic factors are present in the peritoneal fluid of 58% of patients with endometriosis.35 Vascular endothelial growth factors (VEGF) can be produced by activated peritoneal macrophages, refluxed endometrial cells, and endometriotic lesions. VEGF36 is responsible for creating a new blood supply to the newly implanted endometrial cells. VEGF levels are elevated in the peritoneal fluid of women with endometriosis, and they correlate with the stage of the disease. Levels are higher around red lesions than around more mature black lesions.
Peritoneal oxidative stress Lipid peroxidation Increased secretion of cytokines IL-1, IL-6, and IL-8 Tumor necrosis factor RANTES Decreased natural killer cell activity
Other angiogenic factors such as interleukin 1 (IL-1) and IL-6 are also expressed by endometriotic tissue. Once scar tissue forms around the implants, neovascularization is limited.37
Abnormalities of the Immune System Immune Cells
Natural killer cells are an important component of the immune system. Because they are cytotoxic, they have antitumor effects. In patients with endometriosis, this intraperitoneal cytotoxicity is decreased.38 T lymphocytes, which are responsible for cellular immunity, are increased in the peritoneal fluid of patients with endometriosis.39 Both helper and suppressor subtypes of T lymphocytes seem to be increased as well. Their role in the development of endometriosis remains unclear. Considerable evidence also suggests that endometriosis is associated with an increased incidence of autoantibodies of the immunoglobulin G (IgG) and IgA class. Autoantibodies to ovarian and endometrial cells have been reported in patients with endometriosis.40 Inflammatory Cells and Cytokines
A complex cascade of immune events results in an impaired peritoneal environment (Table 49-2). Macrophages, which are the most abundant nucleated cells in the peritoneal fluid, are increased in patients with endometriosis. The increase in number does not correlate with the stage of endometriosis.41 Increased activation of these macrophages is associated with increased secretion of cytokines but not phagocytic activity. The scavenging capacity of these macrophages appears to be impaired, resulting in decreased phagocytosis of endometrial cells.42 A protein similar to haptoglobin on endometriotic epithelial cells may decrease macrophage phagocytic capacity. Impaired clearance supports the pathogenetic hypothesis of implantation. The cytokines that are secreted play a role in the implantation of endometrial tissue as well as in the resulting infertility and pain. Macrophages and monocytes in peritoneal fluid of patients with endometriosis seem to increase the growth and maintenance of endometriotic implants.43 The observed increase in peritoneal fluid macrophages in patients with endometriosis can be linked to the increased expression of monocyte chemoattractant protein-1 (MCP-1).44 MCP-1 is produced by endometrial cells, mesothelial cells, macrophages, and endometriotic implants. The presence of endometrial tissue from patients with endometriosis in the peritoneal cavity increases expression of MCP-1 by the mesothelium.45 Oxidative stress is an activator of MCP-1 expression through nuclear factor κB (NFκB). MCP-1 is the most critical cytokine in the
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macrophage-related pathophysiology of endometriosis. The concentration of MCP-1 in the peritoneal fluid correlates well with the stage of the disease. Cytokines and growth factors are found in higher concentrations in patients with endometriosis.46 Cytokines are small proteins that act as communicators between cells, especially those involved in inflammation and the immune system. These cytokines act in autocrine or paracrine loops to magnify their effect. They promote implantation, proliferation, and survival of the endometriotic tissue and are thought to be mediators in the clinical manifestation of the disease. Levels of several interleukins have been reported to be elevated in the peritoneal cavity of patients with endometriosis. They are secreted by the endometriotic lesions and recruited macrophages. Most interleukins are linked to stimulation of prostaglandins, fibroblast proliferation, and altered immune function. IL-1, which originates from activated macrophages and endometriosis implants, stimulates VEGF47 and IL-6. Although IL-6 has not consistently been shown to be increased in peritoneal fluid, the serum level has been shown to be more predictably elevated. IL-6 is produced by endothelial cells, fibroblasts, and monocytes as well as by eutopic and ectopic endometrium. It has a large number of physiologic reproductive functions, such as a promoter of endometrial proliferation and macrophage activator. Interleukin-8 has also been found to be elevated in peritoneal fluid of patients with endometriosis. IL-8 can promote the implantation and growth of ectopic endometrium in the peritoneal cavity. Because it can also stimulate the adhesion of endometrial stromal cells to fibronectin, it can increase endometrial cell attachment to the mesothelium. IL-8 can also promote the invasion of endometrial cells by increasing the secretion of metalloproteinase,48 and it has been shown to stimulate endometrial cell proliferation in vitro and angiogenesis. Another cytokine chemoattractant for monocytes called RANTES (Regulated on Activation, Normal T-cell Expressed and Secreted)49 is expressed in high concentrations in the peritoneal fluid of patients with endometriosis, and its level correlates with the stage of the disease. It seems to be produced in increased amounts by ectopic endometrial implants in response to chemokines. Tumor necrosis factor (TNF) is another cytokine that is produced in increased amounts and found in higher concentrations in the peritoneal fluid of patients with endometriosis.50 It is recognized as the most commonly elevated cytokine in peritoneal fluid.50 It causes an increase in the adherence of endometrial cells to mesothelial cells and may be involved in infertility because it adversely affects sperm motility and is toxic to embryos.36 The soluble form of intercellular adhesion molecule-1 (sICAM-1) is shed in higher amounts from the endometrium of patients with endometriosis, and this has been shown to correlate with the number of endometriotic implants in the pelvis.51 A prospective cohort study found that sICAM-1, when used in combination with CA-125, was a good marker for deep peritoneal endometriosis.52 Leptin is an adipocyte hormone that is produced by endometriotic tissues.53 Its peritoneal concentration is inversely correlated with the stage of endometriosis.54 Macrophage migration inhibitory factor is a pro-inflammatory cytokine produced by macrophages and endometriotic stromal and glandular cells. Its production is increased by TNF-α.
Macrophage migration inhibitory factor was found recently to be significantly elevated in the peritoneal fluid of patients with endometriosis, but its levels did not correlate with the extent of disease or depth of penetration.55
Oxidative Stress in Peritoneal Endometriosis Macrophages in the peritoneal fluid of patients with endometriosis produce large amounts of reactive oxygen species,56 which may lead to the expression of genes that allow cell adhesion.57 Oxidative stress occurs when levels of reactive oxygen species overwhelm the body’s antioxidant defense system. The concept of peritoneal cavity oxidative stress in patients with endometriosis is an extension of the chronic inflammatory nature of the disorder. Several studies have shown that antioxidant defenses may be altered in endometriosis, leading to an increased risk of oxidative stress. The peritoneal fluid from endometriosis patients may contain low levels of vitamin E (an antioxidant). Mifepristone (RU 486) has been showed to inhibit endometrial cell growth through its antioxidant effects.58 Oxidative stress may contribute in part to infertility through its effects on gametes or gamete interaction.36
Genetics of Endometriosis Two broad groups of genes have been investigated in relationship to endometriosis. The first are a group of genes that may increase the susceptibility to the disease, such as genes involved in detoxification of environmental pollutants. A second group of genes are those that are aberrantly expressed and contribute to the implantation of tissue or to the phenotypic expression of the disease. A large number of genes are aberrantly expressed by the endometrium of patients with endometriosis, suggesting a strong genetic basis for its etiology. A number of epidemiologic observations support this genetic predisposition: 1. Family clustering in humans59 and in rhesus monkeys (the best animal model) 2. Concordance in monozygotic twins60 3. Similar age of onset in affected nontwin sisters61 4. A 6- to 9-time increase in first-degree relatives compared to the general population61 5. A 15% prevalence of endometriosis detected on magnetic resonance imaging (MRI) in first-degree relatives of women with stage III to IV endometriosis.62 Comparing the prevalence of the disease between monozygotic and dizygotic twins, it is estimated that 51% of the prevalence of the disease is attributed to genetic factors. The influence of specific environmental factors in a population of women make it difficult to separate out the genetic contribution to the disease. Therefore, the use of animal models such as the monkey may allow a more controlled assessment of such factors. In monkey colonies, there was evidence of familial aggregation63—the risk for full siblings was higher than that for half siblings (maternal or paternal). Population studies in Iceland64 from all identified cases of endometriosis showed a higher degree of common relatives than a control group of unaffected women, which confirms that the endometriosis group originated from a small number of founder women. A Norwegian study65 showed a greater familial association with women having severe endometriosis.
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Chapter 49 Endometriosis 2. Endometriomas are often multilocated. 3. In serial sections of ovarian endometriomas, mesothelial inclusions are often seen, which are successively transformed in endometriosis. 4. Endometriomas have been found in patients with congenital absence of the uterus (Rokitansky-Küster-Hauser syndrome) and premenarchal girls. Metaplasia of the coelomic epithelium of the pleura might in fact explain the occasional case of endometriosis of the lung. Rectovaginal Endometriosis
Figure 49-6 Stage IV endometriosis; this patient had bilateral endometriomas.
Thus, the genetic influence may be more pronounced in relatives with severe disease. This was also demonstrated in a UK study.61 These findings are typical of diseases that are inherited as complex genetic traits, such as diabetes, asthma, and hypertension. Researchers have suggested that many genes are altered with a higher frequency in patients with endometriosis, including the GALT gene and ICAM-1—an adhesion molecule encoding gene. Genes involved in ovarian steroidogenesis have also been implicated, including the gene encoding for the estrogen receptor and the gene encoding for the progesterone receptor. Aromatase enzyme gene expression seems to be increased within endometriosis lesions. This enzyme is usually not expressed in eutopic endometrium, and increased expression may lead to higher local concentrations. This might explain rare cases of postmenopausal women with active endometriotic lesions. Some of these rare cases have been reported to respond to the administration of aromatase inhibitors. A higher prevalence of the 4 G allele of the plasminogen activator inhibitor-1 (PAI-1) is found in patients with endometriosis.62 This results in hypofibrinolysis and persistence of the fibrin matrix that could support the initiation of endometriotic lesions.
Potential Alternative Hypothesis: Coelomic Metaplasia Theory Endometriomas
The etiology of endometrioma formation is still the cause of many debates (Fig. 49-6). After analyzing serial sections of ovaries with endometriomas, Hughesdon66 suggested that 90% of endometriosis resulted from the adhesion of ovaries to the surrounding structures, which leads to progressive invagination of the ovarian cortex after repetitive bleeding from the endometrial implants on the surface of the ovaries. They would, in fact, constitute a pseudocyst. Some investigators also suggested that endometriomas might be the result of infiltration of functional cysts by endometriosis. Donnez and colleagues67 have suggested an alternative pathophysiology, which is based on coelomic metaplasia of invaginated epithelial inclusions. The pelvic mesothelium on the ovary may undergo metaplastic transformation. This theory is based on a number of observations: 1. 12% of endometriomas are not fixed to adjacent pelvic structures.
Endometrial glands and stroma are often found in the retrocervical or rectovaginal space. The histology of these lesions differs from that of superficial endometriotic lesions.67 Smooth muscle proliferation and fibrosis are constantly present, are similar to adenomyotic nodules, and are responsible for the nodular aspect of these lesions often found on palpation of the rectovaginal wall. These lesions will typically lead to long-term pain and deep dyspareunia. They can be found in the uterosacral ligament, the posterior vaginal wall, or sometimes in the anterior rectal wall.68 They can even extend laterally and affect the ureters. Their histology suggests that they do not originate from deep infiltrating lesions but are more likely to be the result of metaplasia of the müllerian rest, according to Donnez and colleagues.69 Once these nodules are removed, they are not likely to recur.70,71 This suggests that these lesions originate from müllerian rest metaplasia rather than from infiltration of superficial endometriosis. Secretory changes are frequently absent in these nodules during the luteal phase, suggesting that they do not respond to physiologic levels of progesterone. The coexpression of vimentin and cytokeratin in these lesions is characteristic of a mesodermal müllerian origin.69 However, the majority of these deeply infiltrating lesions are associated superficial implants, endometriomas, and pelvic adhesions that suggest that these lesions may have a common pathophysiology with peritoneal endometriosis. They may simply represent a different phenotype of the same disease process. The other potential theories of the origin of endometriosis include the “induction” theory and the venous or lymphatic embolism theory. The induction theory implies that an external factor will induce the mesothelium to transform into endometriotic implants. The venous or lymphatic embolism theory is proposed to explain why endometriosis occurs at distant sites, such as the lung.
ANATOMIC SITES OF ENDOMETRIOSIS Endometriosis is most commonly found in the pelvis and near the tubal fimbria.72 The most common locations, in descending order, are the ovaries, the anterior and posterior cul-de-sac, the broad ligament, and the uterosacral ligaments. The left hemipelvis is the most common location—64% compared to the right hemipelvis. More endometriosis is found on the left ovary, possibly because the sigmoid colon alters intraperitoneal movement of fluid. Tubal endometriosis is relatively uncommon, constituting approximately 5% of all cases.73 However, minimal tubal adhesions of the fimbriae are relatively common. The bowel is the most common extragenital location of endometriosis.74
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Section 7 Reproductive Surgery The most common bowel locations, in decreasing frequency, are the rectum, sigmoid colon, cecum, and terminal ileum. Most bowel lesions are superficial and limited to the serosa. Occasionally, transmural involvement of the bowel occurs, which may cause cyclic diarrhea, rectal bleeding, abdominal distension and, rarely, bowel obstruction. The urinary tract is involved in only 1% of cases,75 and it most often affects the bladder. Symptoms are similar to those associated with recurrent cystitis.76 Endometriosis of the urinary tract should be suspected if cyclical urinary symptoms occur. The ureter can be affected in 0.14% to 1% of cases, more commonly on the left side (63%).
Extrapelvic Endometriosis After surgical procedures, endometrial cells can implant in the scar; therefore, endometriosis has been reported in abdominal scars after hysterectomy, appendectomy, and laparoscopy.77 Perineal endometriosis is also occasionally found in episiotomy scars. Many cases of endometriosis of cesarean scars have also been reported. Rare lung cases of endometriosis leading to cyclic hemoptysis or even pneumothorax78 have been reported and imply that hematogeneous or lymphatic dissemination of endometrial cells is possible. This mechanism can also explain the possible spread to rare locations, such as the brain. Endometriosis may also exceptionally affect the liver, pancreas, kidney, urethra, vertebra, and bones.
PATHOPHYSIOLOGY OF INFERTILITY ASSOCIATED WITH ENDOMETRIOSIS Even though the association between infertility and endometriosis is well established,79 the mechanism of this association remains complex and is not completely understood.80 Many women with endometriosis remain fertile, and fertility decreases as the ASRM score increases.81 The following factors may explain why:
Anatomic Changes Endometriosis, when moderate or severe, will often lead to adhesion formation between different pelvic or abdominal organs. Peritubal or peri-ovarian adhesions81 and tubal wall fibrosis can decrease tubal motility and access to the ovulated oocytes.82 Minor adhesions can also be found inside the tubal lumen and may impair transport of the oocyte.
Immunologic Factors
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The peritoneal environment of women with endometriosis is greatly altered, with abnormal levels of cytokines, growth factors, and inflammatory cells, which are likely to participate in the etiology of endometrial implants.83 These alterations negatively affect sperm motility, oocyte maturation, fertilization, embryo survival, and tubal function. The increased number of peritoneal macrophages observed in the peritoneal fluid of patients with endometriosis will lead to higher phagocytic activity83 against sperm and higher nitric oxide synthetase activity. Higher nitric oxide levels may be toxic to the embryo and may negatively affect sperm function and reduce embryonic implantation.84 The peritoneal fluid of women with endometriosis reduces sperm–oocyte interaction in a dose-dependent fashion.85 Oxidative stress has been associated with gamete and embryo toxicity. The addition of antioxidants such as vitamin C and E to
the embryo culture media, for example, is associated with an increased blastocyst development rate in oxidative-stressed embryos.86 Oxidative stress is also associated with increased DNA damage in patients with male factor infertility.87
Oocyte Maturation Levels of transferrin are higher in the peritoneal fluid of women with endometriosis,88 and such levels have been found to decrease follicle-stimulating hormone (FSH)-regulated granulosa cell differentiation, which may lead to ovarian dysfunction. The granulosa cells of patients with endometriosis have been shown to have lower levels of VEGF,89 which is an important angiogenic and mutagenic factor. This may therefore lead to a decrease in oocyte maturation. Levels of TNF90 in granulosa cells of patients with endometriosis have been found to be increased, and this may affect oocyte maturation.
Effect on Embryo Development and Implantation Patients with stage I and II endometriosis have high levels of antiendometrial antibodies,91 which may reduce implantation. IL-1 and IL-692 are elevated in the peritoneal fluid of patients with endometriosis and are embryotoxic. They may also contribute to the observed decrease in fertility. Luteal phase defects were reported to be more common in patients with endometriosis by earlier studies,46 but these findings have not been confirmed by others. Expression of the HOXA1 and HOXA11 genes,93 which is usually up-regulated during the secretory phase of the menstrual cycle, is not up-regulated in patients with endometriosis. These genes were recently reported to regulate the expression of integrin,94 which plays a crucial role in the embryo’s ability to attach to the endometrium. A decrease in β3 integrin expression has been reported in patients with endometriosis, which might explain the decrease in implantation.95 The initial attachment of the embryo may involve cell adhesion molecules such as β3 integrin. Researchers have, in fact, documented over 100 aberrant regulated genes in eutopic endometrium of patients with endometriosis during embryo implantation.96 These genes affect cell adhesion molecules, secreted proteins, transporters, and immune modulators. It is not known which of these aberrant genes causes the decrease in fertility. The presence of free radicals in the endometrium might also decrease oocyte and embryo quality.97 The expression of enzymes involved in the balance of free radical formation and clearing have been shown to be altered in the eutopic endometrium of patients with endometriosis. Disorders such as abnormal follicle growth, abnormal luteinizing hormone surge, hyperprolactinemia, luteal phase abnormalities, and luteinized unruptured follicle syndrome do not seem to play a major role in the infertility associated with endometriosis. The frequency of spontaneous abortions is not increased. The main mechanisms, which may be causal, are related to immune dysfunction or the abnormal peritoneal environment.
MECHANISM OF PAIN RELATED TO ENDOMETRIOSIS Pain associated with endometriosis is quite complex and is not directly correlated with the extent of disease by the ASRM
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Chapter 49 Endometriosis classification.15,98 The depth of endometriosis lesions is associated with the presence of pain, especially dysmenorrhea. Pain associated with advanced disease can be caused by extensive adhesions, ovarian cysts, or deeply infiltrating endometriosis. Expression of nerve growth factor is associated with endometriosis pain. However, there was no relationship between nerve fibers in these adhesions and pelvic pain. Even patients with early-stage disease (few scattered implants) can experience pain. This pain can be explained in part by the increase in prostaglandins found in these patients. In contrast to the normal endometrium, ectopic endometrium (endometriosis) is the site of at least two molecular aberrations that result in the accumulation of increasing quantities of estradiol and prostaglandin PGE2.99 With the first aberration, the activation of the gene that encodes aromatase (CYP19) increases, leading to an increase in aromatase activity in the endometriotic tissue. This activation is stimulated by PGE2, which is the most potent inducer of aromatase activity in the endometriotic stromal cells. The second important molecular aberration in the endometriotic tissue is the increased stimulation of cyclo-oxygenase-2 (COX-2) by estradiol, which leads to increased production of PGE2. This establishes a circular event leading to an important accumulation of PGE2 in the endometriotic tissue.
DIAGNOSIS OF ENDOMETRIOSIS The definitive diagnosis of endometriosis can only be made surgically. However, several noninvasive methods have been proposed. The classic symptoms are dysmenorrhea, noncyclic pelvic pain, dyspareunia, and infertility. Specific physical signs indicative of advanced endometriosis are listed in Table 49-3. Unfortunately, most patients have only nonspecific signs on physical examination. Physical examination during menstruation is more sensitive in the detection of pelvic disease.
Table 49-3 Symptoms and Signs of Endometriosis Symptoms Reproductive tract Infertility Dysmenorrhea Dyspareunia Noncyclic pelvic pain Gastrointestinal Diarrhea and/or constipation Pain with bowel movement Abdominal cramps Cyclic rectal bleeding Urinary Other Low back pain Signs Adnexal mass Adnexal tenderness Uterine tenderness Cul-de-sac Tenderness Nodularity Mass Uterosacral ligament Tenderness Nodularity Vaginal lesions Cervical lesions
If any of the classic symptoms of endometriosis are present, the positive predictive value is 56% and the negative predictive value is 78%. In addition, the sensitivity is 76% and the specificity is 58%. However, this includes patients with ovarian endometriomas as well. If ovarian disease is excluded, these symptoms would have less favorable statistical parameters for the purposes of diagnosis. Findings on physical examination would improve these parameters.100 The more severe symptoms of dysmenorrhea are associated with the presence of deeply infiltrating disease. There are no laboratory tests that can identify patients with endometriosis with a high degree of sensitivity and specificity. CA-125 levels can be elevated with advanced endometriosis but are typically normal in early-stage disease. Overall, a sensitivity between 24% and 94% and a specificity between 83% and 93% have been reported.101 A meta-analysis on the value of CA-125 has confirmed these observations.102 The search for biomarkers of this disease is quite active. The diagnostic accuracy of serum IL-6 and peritoneal TNFα was shown to be excellent (sensitivity, 90% to 100%; specificity, 67% to 89%).50 Further studies are required before clinical use can be recommended. Other potential markers are endometrial genetic markers such as P450 aromatase or placental protein 14. Ovarian endometriosis (see Fig. 49-6) can be predicted with a high degree of accuracy with ultrasonography. However, nonovarian disease cannot. Furthermore, other imaging modalities such as computed tomography (CT) scan and MRI do not substantially improve the diagnostic accuracy of ultrasound for nonovarian endometriosis. There may be a role for identification of deeply infiltrating lesions that involve the cul-de-sac or lesions in uncommon locations, such as the sciatic nerve. Results of diagnostic tests for patients with gastrointestinal symptoms, such as colonoscopy or barium enema radiography, are typically normal or may occasionally show stricture. Patients with significant urinary symptoms should have a urologic evaluation to rule out interstitial cystitis or potentially endometriosis of the bladder. The differential diagnosis of patients with chronic pain and potential endometriosis is quite extensive. The most common are adhesions, chronic pelvic inflammatory disease, interstitial cystitis, irritable bowel syndrome, and musculoskeletal problems, such as myofascial pain or neuralgias.
Surgical Diagnosis The typical lesions of endometriosis are referred to as pigmented (powder-burn, brown, blue-black, brown, and yellow) and nonpigmented (clear, white, red polypoid, or flamelike) lesions (see Figs. 49-3 and 49-4). Defects in the peritoneum or peritoneal windows may contain these lesions. Adhesions can be subtle, as seen around the fimbriae, or severe dense adhesions that are quite vascular and include the tubes and ovaries. The scoring system for endometriosis, the ASRM classification, is widely used clinically but has a significant intraobserver and interobserver variation (between 38% and 52%).15,103 The positive predictive value of laparoscopic visualization of endometriosis is considered to be approximately 50%. Classic lesions, such as red or black lesions, have a visual accuracy between 90% and 100%. White lesions are associated with endometriosis less often.104 The main pathologies that can be confused with endometriosis are endosalpingiosis, fibrosis, mesothelial hyperplasia, carbon deposits from previous surgery, and malignancy.
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Section 7 Reproductive Surgery Hemangiomas, adrenal rests, and splenosis can also rarely be confused with endometriosis. For this reason, diagnostic laparoscopy should be accompanied with biopsy for lesions that are not clearly endometriosis. Clinical trials for endometriosis management should always be performed with biopsy confirmation.
sequent surgery is less successful than IVF in establishing a pregnancy and should be reserved for patients who require management of pain.110 The use of clomiphene citrate or gonadotropin and IUI in patients with advanced disease should be reserved for patients with normal tubes and minimal adhesive disease. The use of GnRH agonists before a cycle of gonadotropin and IUI has not been clearly established as beneficial.
Associated Disease Processes Surveys of endometriosis patients report increased incidence of atopic disease and other autoimmune phenomena such as thyroid disease. Fibromyalgia and chronic fatigue syndrome are often reported. Endometriosis is associated with increased incidence of ovarian cancer (especially endometrioid and clear-cell type), non-Hodgkin lymphoma, dysplastic nevi, and melanoma. Approximately 75% of neoplasms complicating endometriosis arise in the ovary. Most are endometrioid type (90%); 5% are clear-cell. Extrapelvic malignancies associated with endometriosis tend to be adenocarcinomas. However, sarcomas have also been reported.105
TREATMENT OF ENDOMETRIOSIS IN THE INFERTILE COUPLE The cumulative spontaneous pregnancy rate over 3 years in women with unexplained infertility (i.e., normal pelvis) is significantly higher than in women with untreated minimal or mild endometriosis (54.6 % versus 35.5%; P = 0.048).106 It is estimated that in an infertile couple with stage 1 or 2 endometriosis, the monthly fecundity rate is 3% per cycle. Smoking decreases the chance of pregnancy and live birth in both groups. Medical suppressive therapy with an oral contraceptive agent or gonadotropin-releasing hormone (GnRH) agonist does not improve the pregnancy rate.
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Surgical treatment of minimal or mild endometriosis improves the spontaneous pregnancy rate. However, the absolute amount is open to debate. Two studies have investigated this question with randomized clinical trials: a multicenter Canadian trial and an Italian trial.107,108 The Canadian trial showed statistically significant improvement. The ongoing pregnancy rate was 29% in the treated group and 17% in the nontreated group. The number needed to treat—that is, the number of persons that would need to be treated surgically to achieve an extra pregnancy—was 9 (95 CI, 5–33). The Italian trial did not show any improvement in pregnancy rates. A meta-analysis of these studies showed an improvement but at a reduced rate from that of the Canadian study. Postoperative suppressive medical therapy after surgical treatment does not improve fertility. The only value of medical suppressive therapy appears to be before in vitro fertilization (IVF) in moderate to severe cases. If surgical therapy with early-stage disease fails or if the patient does not wish surgical therapy, the next step is treatment with clomiphene citrate and intrauterine insemination (IUI)109 followed by gonadotropin and IUI. Each is typically attempted for three cycles. In advanced disease, surgical management improves fertility. However, this surgery is complex and requires meticulous dissection. If an initial surgery for advanced disease fails, sub-
In Vitro Fertilization
In a meta-analysis of observational studies, the diagnosis of endometriosis was associated with diminished IVF pregnancy rates111 compared with tubal factor infertility, especially with advanced disease. It is unclear whether the markedly reduced pregnancy rates with IVF in patients with advanced disease are due to previous surgery or simply to the advanced disease itself.112
Endometriomas Endometriomas (see Fig. 49-6) should be removed to confirm they are benign. Removal can improve spontaneous fertility. IVF outcomes have been reported to be similar in patients with and without endometriomas. However, the number of oocytes, fertilization rates, and number of embryos obtained were decreased in women with previously-treated endometriomas compared with those without endometriomas. In relation to IVF, there are several questions that arise about ovarian endometriomas: ●
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Does the presence of an endometrioma compromise IVF outcome? There are no randomized clinical trials. It is likely that small endometriomas (4 cm or less) do not compromise IVF success rates, which therefore makes surgery unnecessary. Does removal of an endometrioma compromise IVF outcome? The preponderance of the evidence suggests that in symptomatic women, we can proceed to safely remove endometriomas without compromising ovarian function or the success of assisted reproduction. Furthermore, removal of large endometriomas (4 cm or more) is sometimes necessary to obtain access to the ovaries. Accidental puncture of an endometrioma during oocyte retrieval may cause infection. Histologic confirmation of the benign nature of a large endometrioma may also be necessary.
The surgical technique used to remove an endometrioma has been evaluated in several trials in an attempt to define what approach results in the least damage to the ovary. Excision by “stripping” the cyst off the ovary will result in ovarian tissue removal with the specimen in more than 50% of cases. In cysts with true capsules, this occurs in only 6% of cases.113 However, few follicles were found in the ovarian tissue removed with the endometrioma. In a randomized trial, excision of the endometrioma was associated with less recurrence and higher fertility rates than fenestration and bipolar coagulation.114 Simple drainage of an endometrioma has been shown to be ineffective.
TREATMENT OF PATIENTS WITH CHRONIC PELVIC PAIN Medical Management Oral contraceptives and nonsteroidal anti-inflammatory drugs (NSAIDs) are used as first-line therapy for chronic pain associated with endometriosis. However, a recent Cochrane review
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Chapter 49 Endometriosis Table 49-4 Medical Therapy for Endometriosis Drugs used for endometriosis Gonadotropin releasing hormone (GnRH) agonists Progestins Medroxyprogesterone acetate Norethindrone acetate Danazol (17-ethinyl-testosterone derivative) Potential new drugs for treatment of endometriosis Tumor necrosis factor α blockers Aromatase inhibitors Matrix metalloproteinase (MMP) inhibitors Antiangiogenic agents Selective estrogen receptor β agonists
concluded that there is little data that supports their efficacy in these patients.115 Several classes of drugs have traditionally been used to manage pain associated with endometriosis (Table 49-4): GnRH agonists, progestins such as norethindrone acetate and medroxyprogesterone acetate, and danazol. Empiric treatment with GnRH agonists without laparoscopy is considered an acceptable approach for the management of chronic pelvic pain after exclusion of other common causes.116 Therefore, response to this treatment does not make the diagnosis of endometriosis. In a study by Ling,117 more than 80% of patients treated with the GnRH agonist had pain relief, but 39% of patients treated with placebo also had pain relief. This placebo response rate is also seen with surgical treatment for endometriosis as well. Progestins
Subcutaneous medroxyprogesterone acetate (Depo-SubQProvera 104) was approved by the U.S. Food and Drug Administration (FDA) for the treatment of endometriosis-related pelvic pain. The formulation contains 104 mg of medroxyprogesterone acetate. It is similar to the Depo-Provera contraceptive injection but contains less hormone. The drug is administered every 12 to 14 weeks subcutaneously. The main concern is the potential loss of bone mineral density (BMD). The bone loss seems to be less pronounced than with the use of GnRH agonists without addback therapy. The drug is also approved as a contraceptive agent. The efficacy is similar to that of GnRH agonists. The typical loss at the spine is about 1.1% for Depo-SubQ-Provera 104 and 3.9% for the GnRH agonist. After 6 months of therapy, the bone loss recovered at 12 months in the Depo-SubQ-Provera 104 group, but a persistent loss was still seen with GnRH agonist. However, there are no data yet on prolonged use of DepoSubQ-Provera 104, and the recommendation is not to use the drug as a contraceptive for longer than 2 years unless other methods are unacceptable. Furthermore, women who wish to conceive after discontinuing the drug should be warned that the resumption of ovulation could be delayed. Several other progestins have been used for the treatment of endometriosis-associated pelvic pain. Medroxyprogesterone acetate at doses of 30 to 50 mg daily is effective. However, the side effects of weight gain, mood changes, and irregular bleeding are not well tolerated. The FDA has also approved norethindrone acetate 5 mg daily with a GnRH agonist. The levonorgestrel intrauterine system (Mirena) has been successfully used for symptomatic endometriosis. A trial also demonstrated pain relief and decreased menstrual blood loss.
The continuation rate dropped to 68% after 1 year of use and stabilized over the remaining years. Patients discontinued the drug because of irregular menstrual bleeding and persistent pain. However, in patients who continued the device, pain was wellcontrolled.118 Gonadotropin-Releasing Hormone Agonists
This class of drugs is highly effective in relieving the pain associated with endometriosis. The drug is given via an intramuscular (leuprolide acetate), subcutaneous (goserelin), or nasal (nafarelin) route. After an initial increase in gonadotropins during the first 10 days, there is a decrease in pituitary secretion secondary to GnRH receptor down-regulation. These drugs are typically given for an initial 6-month course. The majority of patients (75% to 80%) in all clinical trials responded. However, many patients will have recurrence of pain. In a study by Dlugi and colleagues, 54% of patients with moderate to severe pain before treatment reported recurrence of pain within 3 months of a 6-month treatment course.119 Only 37% of patients still had relief after 1 year. Similar results have been reported by many other centers. Miller and colleagues reported a median time to recurrence of pain of 5.2 months.120 About 60% of patients that have recurrence of pain will respond to another six-month trial of GnRH agonists. However, the main concern is the progressive loss in BMD. Menstrual periods return between 2 and 3 months after the last monthly injection, but recovery of BMD takes more time. Add-back therapy was introduced as a way to reduce the hypoestrogenic side effects of GnRH agonists, especially the loss in BMD, but also vasomotor symptoms and atrophic vagina. Other symptoms, such as insomnia, mood disorders, and cognitive dysfunction, may also occur. The mean decrease in BMD after 1 year of GnRH agonist treatment without add-back is between 3% and 7%. Add-back therapy has been proposed for both short-term (less than 6 months) and long-term use (more than 6 months) of the agonist. Many studies have shown that the efficacy is not reduced. Norethindrone (5 mg orally daily) is the most commonly used add-back regimen. Low-dose estrogen (conjugated equine estrogen 0.625 mg) can also be added to norethindrone without loss of benefit in symptom control. Higher doses of estrogen are associated with diminished efficacy in relieving pain symptoms. Breakthrough bleeding with the use of estrogens causes dysmenorrhea. Mood changes and weight gain are the most commonly reported side effects with the progestin. A lower dose progestin such as medroxyprogesterone acetate 2.5 to 5 mg orally can be tried if side effects occur with the higher dose progestin. A lower dose of estrogen such as transdermal estradiol 25 μg has also been tried. These lower doses of progestin and estrogens may not totally prevent bone mineral loss. The addback therapy can be started simultaneously with GnRH agonists or after several months. All patients should take 1000 to 1500 mg daily of calcium and vitamin D 400 to 800 IU daily. If the steroid add-back regimens are not acceptable, a bisphosphonate can be added to prevent osteopenia. The long-term effects of adding this class of drug in women attempting pregnancy are not known. Androgens
Danazol is a 17-ethinyl-testosterone derivative that is as effective as GnRH agonists in relieving the pain associated with
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Section 7 Reproductive Surgery endometriosis. The side effects from this class of drugs are related to their androgenicity and include weight gain, edema, acne, hirsutism, and myalgia. The drug can cause androgenic changes in the lipid profile and raise liver enzymes. Danazol suppresses luteinizing hormone and FSH and induces amenorrhea at the traditional doses used. Typically, 400 to 800 mg daily are used for 6 months. Recurrence of pain occurs with the same frequency and within the same time period as with the GnRH agonists. A new vaginal formulation may have fewer systemic side effects with the same efficacy of pain relief. Gestrinone is a 19-nonsteroidal derivative that acts as an agonist with androgen receptors as well as interactiong with progesterone receptors. Its efficacy and side effects are similar to those associated with danazol. Drugs that are currently under investigation include TNFα blockers,121 inhibitors of MMP,122 antiangiogenic agents,123 and selective estrogen receptor-B (ERB) agonists.124 The ERB agonists probably have their primary action on the immune system. Aromatase inhibitors have been successfully used in a limited number of cases of persistent disease after hysterectomy and bilateral oophorectomy, as well as in patients with intact pelvic organs. The putative mechanism is by suppression of locally produced estrogens from aromatase activity expressed by the endometriotic lesions. Typically, an aromatase inhibitor such as anastrozole 1 mg daily is given with a low-dose oral contraceptive (20 μg estradiol) to prevent ovarian cyst formation and a possible decrease in BMD.125 The addition of anastrozole to a GnRH agonist seems to have prolonged the time to symptom recurrence as well as frequency of recurrence. However, BMD decreased more with the addition of the aromatase inhibitor.126
Surgical Management Two prospective randomized, controlled studies have clearly shown that surgical therapy is superior to no treatment for relief of pain from endometriosis.127,128 There are several observations that can be surmised from these studies: 1. Surgery is more effective than simple diagnostic laparoscopy in the treatment of pain associated with endometriosis. 2. There is a significant placebo effect associated with surgery, especially early on (3 months) that persists in approximately 20% of patients. 3. Between 20% and 40% of patients will not respond to surgery and will continue to experience pain. 4. Surgery is least effective for early-stage disease. It is unclear if excision of endometriosis is superior to simple ablation by cautery or laser. However, patients with deeply infiltrating endometriosis will require excision of the lesions to accomplish a complete removal of disease. Preoperative suppressive medical therapy such as with a GnRH agonist does not improve surgical outcome or decrease the difficulty of the procedure. Postoperative treatment with suppressive therapy with a GnRH agonist for 6 months may delay recurrence of symptoms.
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Interruption of the cervical and uterine sensory nerves by transection of the uterosacral ligaments, a uterosacral nerve ablation,
has been shown not to have any long-term benefit.129 A presacral neurectomy has been shown to be beneficial in patients with chronic pelvic pain and endometriosis when performed with surgical treatment of the endometriosis lesions.130 The procedure is associated with greater relief of midline pain rather than lateral pain. The success of the procedure is dependent on excision of the superior hypogastric plexus (presacral nerve) before extensive branching has occurred. The dissection is actually prelumbar. The landmark on the right is the ureter and right common iliac artery; on the left, it is the sigmoid colon and inferior mesenteric vessels. The floor of the prelumbar space contains the left common iliac vein. The most common postsurgical complications are constipation and urinary urgency.
Hysterectomy Hysterectomy with or without bilateral salpingo-oophorectomy can be considered in patients whose disease fails to respond to conservative management and who do not desire future fertility. Most studies have shown significant pain relief from definitive surgery. Caution should be used in recommending oophorectomy in younger women. However, conserving the ovaries may increase the probability of recurrent pain and the need for reoperation.
Posthysterectomy Recurrence Endometriosis can recur in 5% to 10% of patients after hysterectomy and bilateral salpingo-oophorectomy.131 The role of hormone replacement therapy after surgical castration is controversial. There is a possibility of symptom or disease recurrence. On the other hand, there is the real possibility of severe vasomotor symptoms and osteoporosis. No high-quality data support a particular recommendation. The recurrence rate of endometriosis in hormone replacement therapy was assessed in a randomized, nonplacebo-controlled trial in women who had undergone bilateral salpingo-oophorectomy (90% of patients had also undergone hysterectomy). Hormone replacement therapy consisted of transdermal estradiol delivering 50 μg per day and cyclic micronized progesterone. Patients were followed for a median of 45 months. The risk of recurrence in the treated and nontreated group was 3.5% and 0%, respectively.132 The cases of recurrent endometriosis were observed in women who may not have had total removal of the disease. Hormone replacement therapy is not contraindicated, and the risks and benefits should be discussed with the patient.
Rectovaginal Endometriosis The management of rectovaginal endometriosis is extremely difficult and usually involves the rectosigmoid colon. Patients usually have severe symptoms that may involve the gastrointestinal tract, such as constipation, diarrhea, and painful bowel movements. However, some patients with rectovaginal endometriosis are asymptomatic. These patients do not need treatment. Follow-up studies on a cohort of untreated patients with asymptomatic cul-de-sac disease have shown that most patients do not develop symptoms or further growth of the disease.133 Many patients achieved pregnancy without surgical resection.
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Chapter 49 Endometriosis
Figure 49-7
Endometriosis involving the sigmoid colon.
A
MANAGEMENT OF ENDOMETRIOSIS ON EXTRAGENITAL ORGANS Gastrointestinal Endometriosis Although gastrointestinal symptoms are quite common in women with endometriosis, the overall incidence of bowel involvement is reported to be between 5% and 10%. Endometriosis of the gastrointestinal system typically involves the rectum or rectosigmoid colon (Fig. 49-7). Recurrence of disease after hysterectomy and oophorectomy more commonly involves the bowel. Complete obliteration of the cul-de-sac is a common operative finding. These patients typically present with gastrointestinal symptoms in addition to the typical chronic pelvic pain complex. Excision of disease or intestinal resection can be performed by laparotomy or laparoscopy.134 Rectovaginal fistula and abscess formation are the most serious complications reported.
B Figure 49-8 A, Fibrotic-type endometriosis involving the right hemidiaphragm. The lesions are seen above the liver. Most are obscured by the liver. B, Hemorrhagic-type endometriosis lesions of the right hemidiaphragm.
Respiratory System Diaphragmatic endometriosis can be asymptomatic and noted incidentally at diagnostic laparoscopy (Fig. 49-8). Symptomatic patients often report right-sided chest pain or shoulder pain in association with menstruation that occasionally radiates into the neck or arm and dyspnea. Sometimes these symptoms occur during the nonmenstrual phase of the cycle. These patients seem to have associated pelvic endometriosis that ranges from mild to severe. The right hemidiaphragm is more often involved. Typically, there are smaller sentinel lesions that predict the occurrence of more significant lesions on the posterior diaphragm. Many significant lesions of the right diaphragm will not be seen from a laparoscope placed at the umbilicus, and a view from a right upper quadrant port is necessary. Electrosurgery, laser excision, or surgical excision should be performed carefully because the thickness of the diaphragm ranges between 1 and 5 mm. Medical treatment with GnRH agonists has been reported to have mixed results. Surgical castration has also been attempted, with mixed results in symptomatic patients. Asymptomatic diaphragmatic lesions do not need treatment. Thoracic endometriosis most commonly presents as a rightsided catamenial pneumothorax but can also be manifested by hemothorax, hemoptysis, or pulmonary nodules. The typical symptoms are chest pain and dyspnea. Not all of these patients
have pelvic endometriosis at the time of surgical management of the thoracic disease. Pleural or diaphragmatic endometriosis can be found in less than 25% of cases.135 A chest CT scan may demonstrate pulmonary or pleural nodules, especially if performed during a menstrual period. Chemical pleurodesis is associated with a lower recurrence rate of catamenial pneumothorax than hormonal treatment. However, initial treatment with hormonal therapy is indicated. Catamenial chest pain may persist after pleurodesis and require endocrine manipulation to induce a hypoestrogenic state.
Genitourinary System Endometriosis often involves the peritoneum over the ureter. However, direct ureter involvement is uncommon and has been reported in less than 1% of patients. In patients with rectovaginal endometriosis, the prevalence is higher. Ureteral involvement can be the result of extrinsic compression from extensive endometriosis that surrounds the ureter with significant fibrosis. Intrinsic endometriosis involves the presence of glands and stroma within the wall of the ureter without extension from the surrounding tissues. These lesions can be associated with loss of kidney function. These patients usually have severe pelvic pain,
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Section 7 Reproductive Surgery times of the cycle. Progressive leg and foot muscle weakness, with electromyogram studies showing denervation, can be demonstrated. MRI typically shows a lesion infiltrating the sciatic nerve. CT-guided biopsy can be used to confirm the diagnosis (Fig. 49-9). Two thirds of cases are localized to the right side. Most cases have pelvic endometriosis associated with this disease. Catamenial sciatica can occur without characteristic imaging results. Treatment with a GnRH agonist (leuprolide acetate 3.7 mg every 28 days) with add-back therapy (transdermal estradiol 25 μg) has been shown to reverse the neurologic abnormalities. If symptoms persist, electromyogram studies show worsening of the syndrome; if recurrence occurs after medical therapy, surgery is indicated. In patients who have completed their family, surgical castration with hormone replacement is an option. If this fails or if patients have not yet completed their family, excision of the lesion off the sciatic nerveis suggested. However, this surgery is complex because the lesions often start on the lumbosacral plexus on the piriformis muscle and wind through the sciatic notch.
Figure 49-9 Computed tomography-guided biopsy of endometriosis involving the left sciatic nerve. The needle is introduced through the gluteus muscles toward the piriformis muscle. Notice on the right side the sciatic nerve is clearly distinguished from the surrounding tissue and is seen separate from the piriformis muscle. On the left it is not clearly defined because of the surrounding fibrosis.
PEARLS ●
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dysmenorrhea, and dyspareunia. Some patients have associated urinary symptoms such as hematuria or dysuria. The majority of the patients have significant involvement of the rectovaginal septum with nodules that are often larger than 3 cm. Preoperative imaging studies such as MRI with contrast should be used to evaluate the renal system preoperatively in patients with rectovaginal disease. Ultrasonography will usually not detect these lesions. Medical therapy has been used successfully in a limited number of patients. Most cases of ureteral endometriosis can be treated with excision of the periurethral fibrosis and active lesions without ureter resection.
Sciatic Nerve Involvement Patients with endometriosis of the sciatic nerve can present with hip pain, which is usually localized to the buttock. The pain radiates down the back of the leg, and numbness occurs in areas innervated by the sciatic nerve. The symptoms typically occur in association with a menstrual period but then extend into other
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Intrinsic abnormalities of the endometrium have been identified in women with endometriosis. Several gene abnormalities have been identified that may predispose a woman to endometriosis. Several genes are aberrantly expressed in the endometrium of patients with endometriosis. Dysfunction of the immune system, especially in the peritoneal cavity, is associated with endometriosis. Peritoneal macrophages and their secreted mediators play an important role in the pathogenesis of endometriosis. Peritoneal cavity oxidative stress is important in the pathogenesis of the disease. TNF is the most common cytokine found in the peritoneal fluid. Surgical treatment of endometriosis improves pregnancy rates, but medical treatment does not. Medical treatment of endometriomas is associated with a high recurrence rate; surgical excision is the treatment of choice. GnRH agonists relieve pain in most patients with endometriosis, but recurrence is common. GnRH agonists with add-back therapy are effective in relieving pain symptoms and reducing side effects. Aggressive surgical removal of endometriosis is associated with pain relief in most but not all patients; there is a significant placebo effect. IVF pregnancy rates may be decreased in women with endometriosis.
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54. Bedaiwy MA, Falcone T, Goldberg JM, et al: Peritoneal fluid leptin is associated with chronic pelvic pain but not infertility in endometriosis patients. Hum Reprod 21:788–791, 2006. 55. Mahutte NG, Matalliotakis IM, Goumenou AG, et al: Elevations in peritoneal fluid macrophage migration inhibitory factor are independent of the depth of invasion or stage of endometriosis. Fertil Steril 82:97–101, 2004. 56. van Langendonckt A, Casanas-Roux F, Donnez J: Oxidative stress and peritoneal endometriosis. Fertil Steril 5:861–870, 2002. 57. Guérin P, El Mouatassim S, Ménézo Y: Oxidative stress and protection against reactive oxygen species in the preimplantation embryo and its surroundings. Hum Reprod Update, 7:175–189, 2001. 58. Murphy A, Zhou MG, Malkapuram S, et al: RU486-induced growth inhibition of human endometrial cells. Fertil Steril 74:1014–1019, 2000. 59. Kennedy S, Mardon H, Barlow D: Familial endometriosis. J Assist Reprod Genet 12:32–34, 1995. 60. Hadfield RM, Mardon HJ, Barlow DH, Kennedy SH: Endometriosis in monozygotic twins. Fertil Steril 68:941–942, 1997. 61. Coxhead D, Thomas EJ: Familial inheritance of endometriosis in a British population: A case control study. J Obstet Gynaecol 13:42–44, 1993. 62. Bedaiury MA, Falcone T, Mascha ED, Casper RF: Genetic polymorphism in the fibrinolytic system and endometriosis. Obstet Gynecol 108:162–168, 2006. 63. Hadfield RM, Yudkin PL, Coe CL, et al: Risk factors for endometriosis in the rhesus monkey (Macaca mulatta): A case-control study. Hum Reprod 3:109–115, 2002. 64. Stefansson H, Geirsson RT, Steinthorsdottir V, et al: Genetic factors contribute to the risk of developing endometrisis. Hum Reprod 17:3–9, 2002. 65. Moen MH, Magnus P: The familial risk of endometriosis. Acta Obstet Gynecol Scand 72:560–564, 1993. 66. Hughesdon PE: The structure of endometrial cysts of the ovary. J Obstet Gynecol Br Empire 44:69–84, 1957. 67. Donnez J, Nisolle M, Gillet N, et al: Large ovarian endometriomas. Hum Reprod 11:641–646, 1996. 68. Donnez J, Donnez O, Squifflet J, Nisolle M: The concept of “adenomyotic disease of the retroperitoneal space” is born. Gynaecol Endosc 10:91–94, 2001. 69. Donnez J, Nisolle M, Smoes P, et al: Peritoneal endometriosis and “endometriotic” nodules of the rectovaginal septum are two different entities. Fertil Steril 66:362–368, 1996. 70. Adamyan L: Gynecologic and obstetrics surgery. Additional international perspectives. In Nichols DH (ed) Vaginal Surgery. St-Louis, Mosby Year Book, 1993, pp 1043–1046. 71. Donnez J, Nisolle M, Casanas-Roux F, et al: Rectovaginal septum, endometriosis or adenomyosis: Laparoscopic management in a series of 231 patients. Hum Reprod 2:230–235, 1995. 72. Jenkins S, Olive DL, Haney AF: Endometriosis: Pathogenetic implications of the anatomic distribution. Obstet Gynecol 67:335, 1986. 73. Lyons R, Djahanbakhch O, Saridogan E, et al: Peritoneal fluid, endometriosis, and ciliary beat in the human fallopian tube. Lancet 360:1221–1222, 2002. 74. Bergqvist A: Different types of extragenital endometriosis: A review. Gynecol Endocrinol 3:207, 1993. 75. Vercellini P, Meschia M, De Giorgi O, et al: Bladder detrusor endometriosis: Clinical and pathogenetic implactions. J Urol 155:84–86, 1995. 76. Vercellini P, Pisacteta A, Pesole S, et al: Is ureteral endometriosis an asymptomatic disease? BJOG 107:559–561, 2000. 77. Chatterjee SK. Scar endometriosis: A clinicopathologic study of 17 cases. Obstet 56:81–84, 1980. 78. Moffatt S. Mitchell J: Massive pleural endometriosis. Eur J Cardiothorac Surg 22:321–323, 2002. 79. Decker WH, Lopez H: Conservative surgical treatment of endometriosis and infertility. Infertil 2:155–164, 1979. 80. Olive DL, Schwartz LB: Endometriosis. Infertil 328:1759–1769, 1979.
81. Thornton JG, Morley S, Lilleyman J, et al: The relationship between laparoscopic disease, pelvic pain and infertility: An unbiased assessment. Eur J Obstet Gynecol Reprod Biol 74:57–62, 1997. 82. Frackiewicz EJ, Zarotsky V: Diagnosis and treatment of endometriosis. Expert Opin Pharmacother 4:67–82, 2003. 83. Halme J: Role of peritoneal inflammation in endometriosis-associated infertility. Ann NY Acad Sci 622:266–274, 1991. 84. Osborn BH, Haney AF, Misukonis MA, Weinberg JB: Inducible nitric oxide synthase expression by peritoneal macrophages in endometriosisassociated infertility. Fertil Steril 77:46–51, 2002. 85. Coddington CC, Oehninger S, Cunningham DS, et al: Peritoneal fluid from patients with endometriosis decreases sperm binding to the zona pellucida in the hemizona assay: A preliminary report. Fertil Steril 57:783–786, 1987. 86. Wang X, Falcone T, Attaran M, et al: Vitamin C and vitamin E supplementation reduces oxidative stressed induced embryo toxicity and improves blastocyst development rates. Fertil Steril 78: 1272–1277, 2002. 87. Wang X, Sharma RK, Sikka SC, et al: Oxidative stress is associated with increased apoptosis leading to spermatozoa DNA damage in patients with male-factor infertility. Fertil Steril 80: 531–535, 2003. 88. Treloar SA, Hadfield RM, Montgomery G, et al: The International Endogene Study: A collection of families for genetic research in endometriosis. Fertil Steril 78:679–685, 2002. 89. Mathur SP: Autoimmunity in endometriosis: Relevance to infertility. Am J Reprod Immunol 44:89–95, 2000. 90. Yamashita Y, Ueda M, Takehara M, et al: Influence of severe endometriosis on gene expression of vascular endothelial growth factor and interleukin-6 in granulosa cells from patients undergoing controlled ovarian hyperstimulation for in vitro fertilization-embryo transfer. Fertil Steril 78:865, 2002. 91. Carlberg M, Nejaty J, Froysa B, et al: Elevated expression of tumour necrosis factor α in cultured granulosa cells from women with endometriosis. Hum Reprod 15:1250–1255, 2000. 92. Ulcova-Gallova Z, Bouse V, Svabek L, et al: Endometriosis in reproductive immunology. Am J Reprod Immunol 47:269–274, 2002. 93. Pittaway DE, Maxson W, Daniell J, et al: Luteal phase defects in infertility patients with endometriosis. Fertil Steril 39:712–713, 1983. 94. Taylor HS, Bagot C, Kardana A, et al: HOX gene expression is altered in the endometrium of women with endometriosis. Hum Reprod 14:1328–1331, 1999. 95. Lessey BA, Castelbaum AJ, Sawin SW, et al: Aberrant integrin expression in the endometrium of women with endometriosis. J Clin Endocrinol Metab 79:643–649, 1994. 96. Ota H, Igarashi S, Sato N, et al: Involvement of catalase in the endometrium of patients with endometriosis and adenomyosis. Fertil Steril 78:804–809, 2002. 97. Daftary GS, Troy PJ, Bagot CN, et al: Direct regulation of β3-integrin subunit gene expression by HOXA10 in endometrial cells. Mol Endocrinol 16:571–579, 2002. 98. Whiteside JL, Falcone T: Endometriosis-related pelvic pain: What is the evidence? Clin Obstet Gynecol 46:824–830, 2003. 99. Bulun SE, Zeitoun KM, Takayama K, et al: Aromatase as a therapeutic target in endometriosis. Trends Endocrinol Metab 11:22–26, 2000. 100. Eskenazi B, Warner, M, Bonsignore L, et al: Validation study of nonsurgical diagnosis of endometriosis. Fertil Steril 76:929–395, 2001. 101. Bedaiwy MA, Falcone T: Laboratory testing for endometriosis. Clinic Chim Acta 340:41–56, 2004. 102. Mol BWJ, Bayram N, Lijmer JG, et al: The performance of CA-125 measurement in the detection of endometriosis: A meta-analysis. Fertil Steril 70:1101–1108, 1998. 103. Hornstein MD, Gleason RE, Orav J, et al: The reproducibility of the revised AFS classification of endometriosis. Fertil Steril 59:1015–1021, 1993. 104. Mettler L, Schollmeyer T, Lehmann-Willenbrock E, et al: Accuracy of laparoscopic diagnosis of endometriosis. JSLS 7:15–18, 2003. 105. Jelovsek JE, Brainard J, Winans C, Falcone T: Endometriosis of the liver containing Müllerian adenosarcoma. Am J Obstet Gynecol 191:1725–1727, 2004.
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Chapter 49 Endometriosis 106. Akande VA, Hunt LP, Cahill DJ, Jenkins JM: Differences in time to natural conception between women with unexplained infertility and infertile women with minor endometriosis. Hum Reprod 19:96–103, 2004. 107. Marcoux S, Maheux R, Berube S: Laparoscopic surgery in infertile women with minimal and mild endometriosis. NEJM 337:217–222, 1997. 108. Gruppo Italiano per lo Studion dell’endometriosi: Ablation of lesions or no treatment in minimal–mild endometriosis in infertile women: A randomized trial. Hum Reprod 14:1332–1334, 1999. 109. Deaton J, Gibson M, Blackmer K, et al: A randomized, controlled trial of clomiphene citrate and intrauterine insemination (IUI) in couples with unexplained infertility or surgically corrected endometriosis. Fertil Steril 54:1083–1089, 1990. 110. Pagidas K, Falcone T, Hemmings R, Miron P: Comparison of reoperation for moderate (stage III) and severe (stage IV) endometriosis infertility with in vitro fertilization–embryo transfer. Fertil Steril 65:791–795, 1996. 111. Barnhart K, Dunsmoor-Su R, Coutifaris C: Effect of endometriosis on IVF. Fertil Steril 77:1148–1155, 2002. 112. Pal L, Shifren JL, Isaacson KB, et al: Impact of varying stages of endometriosis on the outcome of IVT–ET. J Assist Reprod Genet 15:27–31, 1998. 113. Muzii L, Bianchi A, Croce C, et al: Laparoscopic excision of ovarian cysts: Is the stripping technique a tissue-sparing procedure? Fertil Steril 77:609–614, 2002. 114. Beretta P, Franchi M, Ghezzi F, et al: Randomized clinical trial of two laparoscopic treatments of endometriomas: Cystectomy versus drainage and coagulation. Fertil Steril 70:1176–1180, 1998. 115. Moore J, Kennedy S, Prentice A: Modern combined oral contraceptives for pain associated with endometriosis. Cochrane Database Syst Rev 2004:CD00474. 116. ACOG: However patients without endometriosis also obtain relief from pain with a GnRH agonist. Washington, DC, ACOG Practice Bulletin no. 51, March 2004. 117. Ling FW: Randomized controlled trial of depot leuprolide in patients with chronic pelvic pain and clinically suspected endometriosis. Pelvic Pain Study Group. Obstet Gynecol 93:51–58, 1999. 118. Lockhat FB, Emembolu O, Konje JC: The efficacy, side effects and continuation rates in women with symptomatic endometriosis undergoing treatment with an intra-uterine administered progestogen (levonorgestrel): A 3 year follow up. Hum Reprod 20:789–793, 2005. 119. Dlugi AM, Miller JD, Knittle J, for the Lupron Study Group: Lupron Depot (leuprolide acetate for depot suspension) in the treatment of endometriosis: A randomized, placebo controlled, double blind study. Fertil Steril 54: 419–427, 1990. 120. Miller JD, Shaw RW, Casper RF, et al: Historical prospective cohort study of the recurrence of pain after discontinuation of treatment with danazol or a GnRH agonist. Fertil Steril 70:293–296, 1998.
121. Nothnick WB, D’Hooghe TM: Medical management of endometriosis: Novel targets and approaches towards the devlopment of future treatment regimens. Gynecol Obstet Invest 55:189–198, 2003. 122. Osteen KG, Yeaman GR, Bruner-Tran KL: Matrix metalloproteinases and endometriosis. Semin Reprod Med 21:155–163, 2003. 123. Hull ML, Charnock-Jones DS, Chan CLK, et al: Antiangiogenic agents are effective inhibitors of endometriosis. J Clin Endocrinol Metab 88:2889–2899, 2003. 124. Harris HA, Bruner-Tran KL, Zhang X, et al: A selective estrogen receptor B (ERB) agonist causes lesion regression in an experimentally induced model of endometriosis. Hum Reprod 20:936–941, 2005. 125. Amsterdam LL, Gentry W, Jobanputra S, et al: Anastrozole and oral contraceptives: A novel treatment for endometriosis. Fertil Steril 84:300–304, 2005. 126. Soysal S, Soysal ME, Ozer S, et al: The effects of post-surgical administration of goserelin plus anastrozole compared to goserelin alone in patients with severe endometriosis: A prospective randomized trial. Hum Reprod 19:160–167, 2004. 127. Sutton CJG, Ewen SP, Whitela N, Haines P: Prospective randomized double blind controlled trial of laser laparoscopy in the treatment of pelvic pain associated with minimal, mild and moderate endometriosis. Fertil Steril 62:696–700, 1994. 128. Abbott J, Hawe J, Hunter D, et al: Laparoscopic excision of endometriosis: A randomized, placebo controlled trial. Fertil Steril 82:878–884, 2004. 129. Proctor ML, Farquhar CM, Sinclair OJ, Johnson NP: Surgical interruption of pelvic nerve pathways for primary and secondary dysmenorrhea. Cochrane Satabase Syst Rev 2003:CD01317. 130. Zullo F, Palomba S, Zupi E, et al:. Effectiveness of presacral neurectomy in women with severe dysmenorrhea caused by endometriosis who were treated with laparoscopic conservative surgery: A 1 year prospective randomized double-blind controlled trial. Am J Obstet Gynecol 189:5–10, 2003. 131. Clayton RD, Hawe JA, Love JC, et al: Recurrent pain after hysterectomy and bilateral salpingo-oophorectomy for endometriosis: Evaluation of laparoscopic excision of residual endometriosis. BJOG 106:740–744, 1999. 132. Matorras R, Elorriaga MA, Pijoan JI, et al: Recurrence of endometriosis in women with bilateral adnexectomy (with or without total hysterectomy) who received hormone replacement therapy. Fertil Steril 77:303–308, 2002. 133. Fedele L, Bianchi S, Zanconato G, et al: Is rectovaginal endometriosis a progressive disease? Am J Obstet Gynecol 191:1539–1542, 2004. 134. Duepree HJ, Senagore AJ, Delaney CP, et al: Laparoscopic resection of deep pelvic endometriosis with rectosigmoid involvement. J Am Coll Surg 195:754–758, 2002. 135. Joseph J, Sahn SA: Thoracic endometriosis syndrome: New observations from an analysis of 110 cases. Am J Med 100:164–170, 1996.
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Laparoscopic Management of Adnexal Masses James L. Whiteside
INTRODUCTION Laparoscopic management of an adnexal mass was first reported more than 30 years ago. During the past decade, laparoscopy has become the dominant management technique for the majority of adnexal masses. Curiously, laparoscopy was accepted as a better approach than laparotomy for adnexal masses with little supporting experimental evidence. This is similar to the widespread acceptance of laparoscopic cholecystectomy, despite a randomized, blinded trial that concluded that the open technique was superior.1 Surgical skill and experience are required to safely and effectively insert trocars and perform laparoscopic surgery. In addition, sound judgment is required to know which patients are appropriate candidates for the laparoscopic approach. The intent of this chapter is to describe not only how to remove an ovarian mass laparoscopically, but also when and in which patients. The most serious mistake that can be made while surgically managing an ovarian mass is to fail to recognize a malignancy. This will result in inadequate staging of the patient’s disease at the very least. Even worse, the stage of the disease may be unknowingly increased by intraperitoneal seeding of the tumor. Unfortunately, there is no combination of diagnostic tests or algorithms that will absolutely differentiate a malignant from a benign adnexal mass. Conversely, erroneously assuming that all pelvic masses are malignant can lead to increased risks and cost associated with unnecessary surgical interventions. The surgeon faced with surgical management of a pelvic mass needs to know: (1) the differential diagnosis and biology of ovarian masses, (2) how to use the tests and other diagnostic information to narrow the differential diagnosis, and (3) how and when to surgically evaluate and remove the mass. Laparoscopic management of an ovarian mass requires the surgeon to exercise both skill and wisdom to minimize the potential adverse outcomes.
ADNEXAL MASSES: DIFFERENTIAL DIAGNOSIS AND BIOLOGY Adnexal masses often present a diagnostic challenge. This stems in part from the fact that adnexal masses can arise from several different organs. In addition, ovarian masses can arise as a result of a broad array of pathology.
even bowel. From any of these organs, a mass can result from hypertrophy, neoplasm, or infection. In a study of 656 women with persistent adnexal masses, 9% were found to originate outside the ovary.2 For this reason, the differential diagnosis of an adnexal mass should always include both ovarian and extraovarian sources (Table 50-1).
Ovarian Tumors To best diagnose and manage adnexal masses, it is important to understand the biology of the entire spectrum of benign and malignant ovarian tumors. Functional Ovarian Cysts
Many women are extremely concerned to learn that they have an ovarian cyst. It is important for the clinician to remember that ovulating women normally develop ovarian cysts 2 to 3 cm in diameter every month. These could be physiologic, such as a dominant follicle or corpus luteum, or functional. The term functional is often applied to cysts that arise from a physiologic process related to ovulation. Functional ovarian cysts are not neoplastic, but are the most common incidental ovarian masses detected on physical and/or ultrasonographic examination. These functional cysts exceed 2 cm in most cases and can be associated with both pain and (occasionally in a thin woman) a palpable mass on pelvic examination. Ultrasonography will reveal a simple cyst filled with fluid with low echodensity. Despite the fact that these physiologic or functional cysts often resolve spontaneously over time, more than 30% of laparoscopies performed to evaluate and manage adnexal masses ultimately find a functional or simple ovarian cyst.3 In some cases, hemorrhage into a functional cyst at the time of ovulation can result in ovarian enlargement and persistent
Table 50-1 Common Extra-ovarian Sources of Adnexal Masses Ectopic pregnancy Hydrosalpinx Tubo-ovarian abscess Paraovarian cyst Peritoneal inclusion cyst
Extra-ovarian Adnexal Masses
Leiomyoma
Although the ovary is the most common origin of an adnexal mass, the source can also be the fallopian tubes, the uterus, and
Fallopian tube neoplasm Bowel abscess or neoplasm
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Section 7 Reproductive Surgery pain. Ultrasonography in these cases will reveal a characteristic complex cyst partially filled with areas of high echodensity. The sudden occurrence of symptoms near midcycle and the spontaneous resolution of the cyst over weeks to months differentiate a hemorrhagic corpus luteal cyst from endometriomas or other more ominous lesions. Observation with serial ultrasonography is the most common management for functional ovarian cysts as well. Follow-up ultrasonography in 4 to 6 weeks usually demonstrates partial or complete resolution. Although the presence of a functional cyst larger than 2 cm might increase the risk of ovarian torsion, the relatively remote risk of this emergency does not justify more aggressive preventive management. Surgical management is sometimes required for patients with apparently functional cysts who experience severe and prolonged pain unresponsive to medical management to exclude intermittent torsion or other pathology. Removal of functional cysts is usually somewhat bloody and can rarely be performed without rupturing the cyst. Fortunately, rupturing a functional cyst has no known adverse effect. In some cases, the cyst wall can be completely removed by peeling this thin layer from the enclosing ovarian epithelium. In most cases, this is difficult because of the frailty of the cyst wall, and a small section can be sent for histologic examination to verify that the cyst is functional in nature. Endometriomas
Endometriomas often pose a difficult management challenge. The most likely cause of endometriosis is retrograde menstruation, as first proposed by Sampson in 1927. Patients with this disease are believed to have some other deficiency, because retrograde flow of endometrial cells occurs in 90% of women, but most of them never develop endometriosis.4 Theoretically, an endometrioma forms when endometriosis implants on the ovarian surface and invaginates to create a cyst. Active endometriosis implants incorporated in the cyst wall continue to secrete blood and cellular material, which accumulate to form a chocolate cyst. Because these endometrial cells implant on the ovarian epithelium and invade into the ovarian stroma, a clear dissection plane is often difficult to find during cystectomy. Ovarian Neoplasms
Ovarian neoplasms can be either benign or malignant and can be further classified into three groups, according to the type of cells from which they originate (Table 50-2): ● ● ●
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epithelial cell neoplasms germ cell neoplasms sex cord–stromal cell neoplasms
The risk of malignancy is influenced by the cell type of origin, with approximately 90% of malignancies arising from epithelial cells. The cell type origin of ovarian tumors varies according to the woman’s age. These three groups have some anatomic correlation. Epithelial cells cover the surface of the ovary. The remainder of the ovary is made up of stroma, which can be further divided into the cortex and medullary portions. Germ cells are contained primarily in the cortical portion of the ovary, whereas sex cord cells are contained primarily in the medullary portion. Stromal cells are contained throughout the ovary.
Table 50-2 Types of Ovarian Neoplasms Epithelial–stromal neoplasms Serous, mucinous, endometroid, clear cell Benign Borderline Malignant Epithelial–stromal Adenosarcoma Transitional cell (Brenner and non-Brenner type) Germ cell neoplasms Mature cystic teratoma Immature teratoma Monodermal teratoma (e.g., struma ovarii) Dysgerminoma Yolk sac tumor (endodermal sinus tumor) Embryonal carcinoma Choriocarcinoma Sex cord–stromal neoplasms Granulosa cell tumor Thecoma Sertoli-Leydig cell tumor Sertoli cell tumor Leydig cell tumor Fibroma Fibrosarcoma Sclerosing stromal tumor Metastatic tumors Breast cancer
Several clinical risk factors have been identified that increase the risk that any ovarian mass will be a malignant neoplasm. One of the most important is age. Before age 15, many ovarian tumors are malignant.5 In woman between ages 20 and 45, only the minority of ovarian tumors will be malignant. The risk increases with age thereafter, such that an ovarian tumor discovered in a woman between ages 60 and 69 is 12 times more likely to be malignant than a tumor in a woman between ages 20 and 29.6 Other important risk factors for malignant tumors include a positive family history and nulliparity.
SPECIFIC OVARIAN NEOPLASMS The ovary is a complex and dynamic structure that is associated with an extensive list of benign and malignant neoplasms, and the obstetrician/gynecologist must ultimately be familiar with all of these. The following is a brief description of some of the most commonly encountered ovarian neoplasms.
Epithelial Cell Tumors Serous and mucinous tumors are the most common ovarian epithelial cell tumors, and the majority are benign (Table 50-3). The fact that they are mostly benign allows a laparoscopic approach. Serous
Serous cystadenomas and cystadenocarcinomas are common, accounting for roughly 30% of all ovarian neoplasms and 40% of ovarian malignancies. On histologic examination, serous tumors will be found to be lined with ciliated columnar cells. Approximately 60% of serous ovarian neoplasms are benign, 15% are borderline, and 25% are frankly malignant. Benign serous cystadenomas comprise 25% of all benign ovarian tumors, and 25% will be bilateral.
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Chapter 50 Laparoscopic Management of Adnexal Masses Table 50-3 Frequency of Malignancy of Ovarian Neoplasms Type
Percent of Tumor Type
Serous Benign Borderline Malignant
60% 15% 25%
Mucinous Benign Borderline Malignant
80% 10% 10%
Teratoma Benign Malignant
96% 4%
From Cotran RS, Kumar V, Collins T, Robbins SL: Robbins Pathologic Basis of Disease. Philadelphia, WB Saunders, 1999.
Malignant serous cystadenocarcinomas are the most common ovarian malignancies, accounting for almost 50% of all malignant ovarian tumors. They are the fifth most common cancer in women in the United States. These tumors usually occur in women between ages 40 and 65 and are bilateral in 65% of cases. Borderline ovarian tumors are less common than either benign or frankly malignant tumors and are bilateral in 30% of cases. On transvaginal ultrasonography, serous cystadenomas are often seen as large, thin-walled cystic ovarian masses with an echodensity similar to water. Internal septa and solid areas suggest malignancy. During laparoscopy, tumor wall irregularity (papillae, nodularity), fixation to surrounding tissues, and solid components all suggest malignancy. The 10-year survival rate for women with serous cystadenocarcinomas is approximately 15%. Mucinous
Mucinous cystadenomas and cystadenocarcinomas are also very common, accounting for 20% of ovarian tumors and 10% of malignancies. They can attain a huge size, often filling the entire pelvic and abdominal cavities. Compared to serous ovarian tumors, they are more often unilateral, large, and multiloculated. These loculations contain thick gelatinous fluid. On histologic examination, mucinous tumors are lined with nonciliated columnar cells. Approximately 80% of mucinous ovarian neoplasms are benign, 10% are borderline, and 10% are frankly malignant. Mucinous cystadenomas account for 25% of all benign ovarian neoplasms. Their peak incidence of occurrence is between ages 30 and 50, and they are bilateral in 5% of cases. Borderline and malignant mucinous tumors tend to occur in slightly older women, with a peak incidence of occurrence between ages 40 and 70. Malignant mucinous cystadenocarcinomas make up 10% of primary malignant ovarian neoplasms and are bilateral in up to 20% of cases. The 10-year survival rate is approximately 34%. Mucinous tumors can be associated with an uncommon malignancy called pseudomyxoma peritonei. This condition is characterized by metastatic spread of well-differentiated mucinsecreting columnar cells along the peritoneal surfaces, usually from a primary mucinous tumor of the appendix. It is believed that this condition can result from intraperitoneal spillage of the
contents of a borderline or malignant mucinous ovarian tumor. However, most cystic ovarian mucinous tumors associated with pseudomyxoma peritonei will be found to be metastases from a primary appendiceal tumor. Endometrioid carcinomas and clear-cell carcinomas make up 20% and 6% of all malignant ovarian neoplasms, respectively, and are bilateral in 40% of cases.
Germ Cell Tumors Teratomas
Teratomas are the most common ovarian germ cell tumors and can be either benign (mature) or malignant (immature). Mature cystic teratomas are benign tumors commonly referred to as dermoids and account for about 25% of ovarian neoplasms. They are most common during reproductive life and are often incidental findings. Although 20% of dermoids are bilateral, it is not recommended to bivalve the ovary in search of a dermoid that is not seen on preoperative ultrasound. Mature cystic teratomas are derived from at least two of the three germ layers: ectoderm, endoderm, and mesoderm. Most frequently, their cyst walls contain skin with sebaceous glands and hair follicles and thus contain greasy, yellow sebaceous material and hair. Less commonly, these tumors include cartilage, bone, thyroid tissue, or other structures. Struma ovarii is a particular type of mature teratoma comprised of more than 80% thyroid tissue and can be associated with hyperthyroidism. Immature teratomas are rare, making up only 4% of ovarian teratomas. Unlike the pattern seen in most ovarian tumors, immature teratomas are more frequent at a younger age, and most present before age 18. Histologically, immature teratomas are composed of partially differentiated structures that resemble fetal or embryonal cell types. Neural elements, cartilage, and epithelial tissues are common. Immature teratomas are often solid; most are unilateral, in contrast to mature cystic teratomas. Treatment for immature teratomas consists of surgical resection of the affected ovary and postoperative chemotherapy. In younger patients, an attempt is made to preserve fertility by conserving the uterus and unaffected ovary. The 5-year survival rate is between 60% and 90%, depending on the grade and stage of the tumor. Chemical Peritonitis
A unique management concern regarding benign cystic teratomas is that untreated intraperitoneal spill of their sebaceous contents can result in chemical peritonitis. Clinically, patients present with postoperative fever and ileus, and can develop peritoneal granulomas, adhesions, and even a perihepatic mass.7,8 The risk of chemical peritonitis has two implications for the laparoscopic surgeon. First, if a cyst punctured during laparoscopy is found to contain sebaceous material, a cystectomy or oophorectomy should immediately be performed. Leaving behind a leaking teratoma can lead to serious consequences. Second, when a dermoid cyst is removed laparoscopically, cyst rupture (reported to occur in approximately half the cases) must be appropriately treated with copious irrigation (i.e., 2 to 5 L) until no oily material can be seen floating on the fluid surface.9–11 Subsequent peritonitis has not been reported using this approach after spillage from a mature cystic teratoma.
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Section 7 Reproductive Surgery Sex Cord–Stromal Cell Tumors These are tumors derived from the mesenchymal stroma of the gonad and account for 5% to 10% of all ovarian neoplasms. Probably the most unusual aspect of this group of tumors is that many are able to synthesize and secrete steroid hormones. Granulosa cell tumors are the most common of this group and account for 5% of all malignant ovarian tumors. They may be nonfunctional, estrogenic or, least commonly, androgenic. Approximately 5% occur before puberty, where they are associated with precious puberty. They are most common in the reproductive years, where they are associated with endometrial cancer. Histologically, they are characterized by Call-Exner bodies. These neoplasms have a good prognosis despite a tendency to recur. Fibromas are solid benign tumors that consist entirely of fibrous tissue and do not secrete hormones. They make up approximately 4% of ovarian tumors and can be associated with Meig syndrome, a rare combination of an ovarian fibroma, ascites, and pleural effusion.
PREOPERATIVE EVALUATION OF AN OVARIAN MASS
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The most important diagnostic questions to be answered before surgery are (1) What is the origin of the mass? and (2) Is it benign or malignant? Although bimanual pelvic examination is the time-honored method of screening for pelvic masses, this technique has marked limitations for evaluating adnexa, especially in the presence of obesity, uterine enlargement, or abdominal scarring.12 History, physical examination, and ultrasonography can usually determine the origin of an adnexal mass. For ovarian masses, a combination of pelvic examination, ultrasonography, and serum CA-125 level is the best way to determine the risk of malignancy.12–14 Certain ultrasonographic characteristics have been found to be strongly associated with malignancy (see Chapter 30). Ovarian tumors are more likely to be malignant if ultrasonography reveals them to be multiloculated, septated, mixed cystic and solid, bilateral, or associated with ascites.15 However, almost two thirds of multilocular and solid tumors will be benign.16,17 Combining serum CA-125 with these ultrasound criteria has been used in women who are postmenopausal as the risk of malignancy index.15 Other investigators have found color flow Doppler ultrasonography to be helpful, because an ovarian lesion is more likely to be malignant if a solid element of the mass demonstrates central blood flow.18 Multiple preoperative assessment models have been developed for adnexal masses.16–28 A significant limitation of many of these models is that they were developed and validated on the same population. Mol and colleagues tested the external validity of most of these models and found that although they could be of value in preoperative assessment, their diagnostic performance was not as good as reported in their original publications.27 None of the externally validated likelihood ratios are sufficiently great as to be diagnostically conclusive.27 Likelihood ratios are the likelihood that a given test result would be expected in a patient with the target disorder compared to the likelihood that that same result would be expected in a patient without the target disorder. Although likelihood ratios may not
Table 50-4 Society of Gynecologic Oncologists and American College of Obstetricians and Gynecologists Referral Guidelines for a Newly Diagnosed Pelvic Mass* Premenopausal Woman CA-125 > 200 U/mL Ascites Evidence of abdominal or distant metastasis (by examination or imaging study) Family history of breast or ovarian cancer (in a first-degree relative) Postmenopausal Woman CA-125 > 35 U/mL Ascites Nodular or fixed pelvic mass Evidence of abdominal or distant metastasis (by examination or imaging study) Family history of breast or ovarian cancer (in a first-degree relative) *Women with pelvic masses who meet these criteria should be referred to a gynecologic oncologist. From ACOG: The role of the generalist obstetrician-gynecologist in the early delection of ovarian cancer. ACOG Committee Opinion no. 280, December 2002. Obstet Gynecol 100:1413–1416, 2002.
be as familiar a concept as sensitivity and specificity, they are calculated from these values and are a more logical means of understanding diagnostic value. Pretest probability can be multiplied by the likelihood ratio of a given test to render the post-test probability. Likelihood ratio values can be positive (rule in a diagnosis) or negative (rule out a diagnosis). What is curious about these models is the relative consistency of the likelihood ratio results and that additional information, such as age and menopausal status, does not dramatically alter the likelihood ratio results between the studies. Unfortunately, these models have significant rates of false-negative and falsepositive results, regardless of the criteria and cutoff values used. The American College of Obstetricians and Gynecologists (ACOG) and the Society of Gynecologic Oncologists (SGO) have jointly published guidelines that help determine when a women with a newly diagnosed pelvic mass should be referred to a gynecologic oncologist (Table 50-4).29 This conservative model accurately predicts which women with ovarian masses are at low risk of malignancy, with a negative predictive value of 92% for premenopausal and 91% for postmenopausal women.30 However, the women at highest risk according to this model will often be found to have a benign lesion, with a positive predictive value of 34% for premenopausal and 60% for postmenopausal women.
SURGICAL APPROACH Laparoscopy versus Laparotomy An important question that must be answered whenever a patient presents with an ovarian mass is whether the mass should be approached laparoscopically or via laparotomy. The answer is not simple and will ultimately depend on the experience and philosophy of the physician and the desires of the patient. A useful approach for the woman presenting with a pelvic mass has been proposed, which places each patient into one of three risk categories for having a malignancy: low, intermediate, and high (Fig. 50-1).22 A woman at low risk can be observed for 3 months or evaluated with diagnostic laparoscopy according to the patient’s preference. A woman at intermediate risk can be
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Premenopausal
Ultrasound suspicious
Postmenopausal
Ultrasound not suspicious
Consider CT or MRI
Tumor < 10 cm
Tumor > 10 cm
CA-125
CA-125
< 60 U/mL
> 60 U/mL
Ultrasound not suspicious
??? Surgical evaluation
Re-evaluate in 3 months
Diagnostic laparoscopy
Consider CT or MRI
Ultrasound suspicious Consider CT or MRI
Re-evaluate vs. diagnostic laparoscopy
Surgical evaluation
Figure 50-1 Algorithm for preoperative evaluation of an ovarian cyst. A distinction is made here between a diagnostic laparoscopy and surgical evaluation. Depending on surgeon skill, availability of gynecologic oncology backup, and overall clinical suspicion for malignancy, surgical evaluation could include laparoscopy, yet consideration should be given in these circumstances to performing a laparotomy.
evaluated with diagnostic laparoscopy. Laparoscopic treatment of the mass is appropriate in the absence of surgical evidence of malignancy. Women at high (10% or greater) risk of malignancy should be evaluated surgically, most commonly via laparotomy. In select circumstances, laparoscopy can be used for surgical evaluation, assuming that the laparoscopist has both the appropriate experience and gynecologic oncologist backup.
Intraoperative Tumor Rupture Intraoperative rupture of some ovarian cysts that are later found to be malignant is unavoidable, regardless of the preoperative criteria or surgical approached used. One study of 32 patients found an overall rate of tumor rupture of 25% for laparoscopy compared to 9% for laparotomy.31 This occurrence appears to worsen the patient’s prognosis, although there are conflicting data. Although some studies have found no impact of intraoperative tumor rupture on subsequent survival,32–34 others have shown decreased survival.35–38 The only prospective assessment of the impact of intraoperative tumor rupture found a significantly lower survival rate for women with stage I ovarian carcinoma after rupture, although not as low as for women whose tumor ruptured spontaneously before surgery.38 The greatest impact of intraoperative rupture was for serous tumors, where the 9-year survival rate declined from 86% to 50%. Furthermore, many oncologists will recommend chemotherapy after an intraoperative spill of a welldifferentiated stage I a cancer that usually would not have received such treatment. Certainly, spillage of cyst contents into the peritoneal cavity should be avoided when ovarian malignancy is a possibility.
Table 50-5 Surgical Staging for Ovarian Cancer Evaluate Is the tumor unilateral or bilateral? Does the tumor appear on the external surface of the ovary? Is the tumor capsule intact? Has the tumor ruptured? Biopsy Any suspicious lesions Three sites of pelvic peritoneum Cul-de-sac peritoneum Right and left abdominal gutter Undersurface of the right diaphragm Partial omentectomy Para-aortic and pelvic nodes Peritoneal washings
Surgical Staging Regardless of the surgical approach used to treat an ovarian malignancy, adequate surgical staging is imperative (Table 50-5). One study of 100 women with ovarian cancer referred to a gynecologic oncologist after surgical diagnosis found that only 25% had adequate staging.39 More than 30% were ultimately found to have more advanced stage disease than reported based on the initial surgery. One factor that contributes to inadequate staging at the initial surgery is the discordance between intraoperative frozen section and subsequent diagnosis based on permanent section. Making a diagnosis of borderline malignancy is especially difficult on frozen section. Several studies have documented a greater than 5% discordance between these two techniques.40,41
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Section 7 Reproductive Surgery The problem is that patients erroneously determined intraoperatively to have benign disease based on frozen section are unlikely to be adequately staged. In light of the inherent inaccuracy associated with frozen section, surgeons should consider staging patients with suspicious ovarian masses even if the interoperative diagnosis is benign. Moreover, surgeons should discuss intraoperative diagnostic limitations with their patients before surgery, irrespective of approach.
vessels. Many laparoscopic surgeons do not use the suprapubic site but rather place an accessory port just above the level of the umbilicus lateral to the rectus muscle on the patient’s left side. The latter approach allows the surgeon to operate comfortably with two hands. Specimen removal will often require placement of a 10-mm or greater port in one of the secondary sites. This larger port can be placed initially, or a 5-mm site can be dilated to 10 mm.
LAPAROSCOPY APPROACH FOR OVARIAN MASSES
Pelvic Washings and Peritoneal Cavity Inspection
Laparoscopic management of properly selected ovarian masses has become a standard part of modern obstetrics and gynecology.3 In one study of 396 women who underwent laparoscopy for a low-risk adnexal mass, only 2% of patients were ultimately found to have a malignancy.3 This low rate is related both to a low prevalence of malignancy among women with ovarian cysts in a general population and the efficacy of preoperative diagnostic testing. Because the possibility of a malignancy can never be eliminated preoperatively in patients with an ovarian mass, consideration should be given to obtaining consent for an open staging procedure in patients with a suspicious mass.
Oophorectomy versus Cystectomy Two approaches are commonly used for evaluation and treatment of ovarian cysts: oophorectomy and cystectomy. Oophorectomy, with or without removal of the fallopian tube, is the preferred approach for women no longer desiring fertility and for any lesion at moderate to high risk of being malignant to minimize the risk of intraperitoneal spillage. Cystectomy is preferred for low-risk ovarian lesions in women who want to preserve their fertility and young women with only one remaining ovary to preserve hormonal function. Incomplete removal of a cyst is not the procedure of choice but is sometimes necessary. In the case of a small cyst that appears to be functional in nature, aspiration of the cyst contents for cytology, followed by full-thickness biopsy of the cyst wall, is a reasonable technique to resolve the cyst while verifying that it is not a neoplasm. In the case of an endometrioma with no identifiable cyst wall that can be removed, aspiration of the chocolate cyst contents followed by ablation of the internal surface of the cyst may be necessary, but it is associated with an increased recurrence risk. In every case, a full-thickness biopsy of the cyst wall should be sent for pathologic evaluation.
Laparoscopic Setup
752
Any standard laparoscopic technique can be used for entry. When dealing with a large lesion it is prudent to use an open laparoscopic technique or a left upper quadrant site. The latter is especially useful for removal of a mass in a pregnant patient. If an open umbilical technique is used, the mass can be removed through this port as well. During removal, the laparoscope is placed through one of the secondary ports to visualize the removal. Most laparoscopists use two or three secondary 5-mm ports for operative procedures. The most common configuration is a suprapubic port 3 to 4 cm above the pubic symphysis and lateral ports at McBurney’s point on the right and the corresponding Hurd’s point on the left, taking care to avoid the epigastric
Before beginning the operative procedure, pelvic washings should be collected. In the absence of ascites, 50 to 100 mL of saline solution is introduced into the peritoneal cavity and aspirated from the cul-de-sac, paracolic gutters, and beneath each hemidiaphragm. The abdominal cavity should be carefully inspected for signs of metastases by taking note of the appearance of the uterus, fallopian tubes, ovaries, cecum, paracolic gutters, colon, liver, gallbladder, diaphragm, omentum, and peritoneal surfaces. The ovarian capsule should be carefully inspected to determine if it is intact or has been penetrated by tumor. Any suspicious excrescences should be biopsied and sent for pathologic evaluation. If malignancy is encountered, a gynecologic oncologist should be consulted intraoperatively. If malignancy is encountered and an oncologist is not available, minimal tissue manipulations and irrigation of trocar sites is recommended. Prognosis is best with rapid reoperation.
Laparoscopic Oophorectomy Laparoscopic oophorectomy is an important technique to be mastered by obstetrician/gynecologists. In addition to minimizing the risk of intraperitoneal spill of ovarian cyst contents, special efforts need to be made to avoid ureteral injury. Knowing the course of the ureters and their relation to the ovarian blood vessels is essential. The ovarian artery originates from the abdominal aorta and courses with the ovarian vein and lymphatics through the infundibulopelvic ligament (i.e., ovarian suspensory ligament). At the superior end of the infundibulopelvic ligament, the ureter crosses beneath the ovarian vessels. The ureter then courses immediately beneath the ovary in the retroperitoneal space adjacent to the peritoneum. It is at these two locations that the ureter is at risk of injury during oophorectomy. The first step in a laparoscopic oophorectomy is to identify the ureter. If the ureter can be clearly identified transperitoneally by its peristalsis and found to be safely beneath the level of the infundibulopelvic ligament, oophorectomy can be performed without opening the pelvic sidewall peritoneum. However, in cases where the ureter cannot be seen because of obesity, adhesions, or thickened peritoneum, the pelvic sidewall peritoneum should be opened. The infundibulopelvic ligament is put on tension and the peritoneum is opened to identify the ureter. The ovarian vessels are skeletonized and occluded using one of a variety of techniques: bipolar cautery, ultrasonic scalpel, a stapling device, or an endoligature (Fig. 50-2). Careful dissection using scissors or one of these power sources is then used to isolate and occlude the utero-ovarian ligament, thereby separating the ovary and tube from their attachments. The dissection bed should be inspected for hemostasis before removal of the ovary from the peritoneal cavity. At the conclusion of laparoscopy, the
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A
A
B
B
Figure 50-2 A, The retroperitoneal space has been opened and the ovarian vessels are retracted laterally. The ureter is located on the medial leaf of the peritoneal incision. B, After isolation of the ovarian vessels from the surrounding structures, a bipolar device can be safely applied.
Figure 50-3 A, An incision is made on the ovarian cortex to identify the underlying cyst. B, The cortex is dissected off the cyst and the intact cyst is free.
hemostasis of all vascular pedicles should be reevaluated as the intra-abdominal insufflation pressure is decreased.
the ovarian tissue overlying the cyst must be carefully incised without rupturing the cyst. Having carefully inspected the ovary, a site on the ovary should be selected that appears (1) to have the thinnest layer between the cortex and the cyst wall and (2) to have good laparoscopic exposure. Some surgeons use monopolar cautery with the cutting current set at 10 amperes for this purpose. Others prefer gently incising the tissue with sharp scissors. Once a defect is made, the ovarian tissue is bluntly separated from the cyst wall (Fig. 50-3A). The ovarian cortex is held with a grasper and gently peeled away from the underlying cyst (see Fig. 50-3B). This can be facilitated with aid of water dissection from the laparoscopic suction–irrigator. In areas where connections between the cortex and cyst wall do not separate easily, sharp dissection should be used to avoid cyst rupture and spill.
Laparoscopic Ovarian Cystectomy For women with ovarian cysts at low risk of being malignant who desire to maintain their fertility, an ovarian cystectomy is often the best option. With the exception of functional cysts and endometriomas, the cyst wall of benign ovarian cysts can often be easily separated from the ovarian cortex and the cyst removed intact from the peritoneal cavity intact. The goal is to preserve as much normal ovarian cortex as possible, because this is the area containing primordial follicles. In cases where little ovarian tissue remains, the contribution of a small remnant to subsequent fertility and hormone secretion may be minimal. As with oophorectomy, ovarian cystectomy begins with collection of peritoneal washings and careful inspection of the peritoneum for signs of possible implants. Considerable finesse is then required to remove ovarian cysts intact without spillage. Ovarian cysts are ordinarily contained beneath a layer of ovarian epithelium that can be extremely thin. To begin a cystectomy,
Removal of the Ovary or Cyst from the Peritoneal Cavity Once the ovary or a cyst has been excised, the next challenge is to remove the specimen from the peritoneal cavity without
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Section 7 Reproductive Surgery spilling any cyst fluid into the peritoneal cavity. The ideal approach is to place the entire specimen intact into a retrieval bag for extraction. Retrieval Bags
Several types and sizes of retrieval bags are available. They can be grouped into two main categories: clear polymer bags and opaque fabric bags. The polymer bags have the advantage of easier intra-abdominal manipulation and better visibility, but are fragile and can be easily punctured or ruptured during extraction of the specimen. The fabric bags have more strength and thus cannot be ruptured, even if excessive force is applied while trying to remove a specimen larger than the port incision. They are somewhat more difficult to place into the abdomen and decrease visibility. In either case, it is important to select a bag big enough to hold the intact specimen whenever possible.
A
Cyst Aspiration and Morcellation in the Bag
754
After the specimen is placed into the retrieval bag, the opening of the bag is drawn up into one of the port sleeves. A 10-mm suprapubic or lateral port is usually used, but the umbilical port can also be used if the laparoscope is first placed through an alternative port. The selected incision is encircled with absorbent material to prevent inadvertent fluid contamination of the subcutaneous tissue during specimen extraction. The port sleeve containing the bag opening is removed from the abdominal wall, thus delivering the bag opening through the trocar incision (Figure 50-4). At this point, ovarian cyst contents can be aspirated with little risk of spillage into the peritoneal cavity. Care must be taken to avoid puncturing a polymer bag with the aspiration needle. When the solid portion of the ovary is too large to deliver through the fascial incision, the resected tissue must be morcellated. Grasping and removing small pieces of the ovary with a Kocher forceps while the specimen remains within the intraabdominal portion of the bag can do this. Once enough tissue has been removed, the bag and the remaining contents can be delivered though the incision with gentle twisting traction. Excessive traction will rupture a polymer bag, releasing its contents into the peritoneal cavity. In some cases, the fascial incision must be extended. It is important to remember that most manufacturers of retrieval bags do not recommend morcellation within the bag but rather extending the incision to accommodate the intact removal of the cyst. An alternative method for removing large specimens is to use a colpotomy incision, because the vagina and peritoneum are more distensible than the abdominal wall muscle and fascia. After the specimen has been placed in a bag, a colpotomy incision can be performed laparoscopically with a power-cutting device while tenting the posterior cul-de-sac with a vaginal probe. The closed bag is transferred to a vaginal grasping instrument for removal. Alternatively, a 10-mm laparoscopic probe can be carefully placed through the posterior vaginal fornix so that the pneumoperitoneum is maintained and standard laparoscopic instruments can be used for removal. The colpotomy incision is closed either laparoscopically or transvaginally. After removal of a suspicious mass, a frozen section can be obtained to determine if it is malignant, although this is not as accurate as a permanent section. The approach for the remainder of the surgery can be based on the presumptive diagnosis. The
B Figure 50-4 The cyst is ruptured within a retrieval bag and morcellated without spill into the peritoneal cavity.
defect in the ovary is usually not closed. Suture on the cortex can increase adhesion formation. Occasionally with a large defect an interrupted stitch can be placed deep within the cavity to approximate the bivalve ovary. Treatment of Intraperitoneal Spill
If the contents of a suspicious ovarian cyst are spilled within the peritoneal cavity, the primary treatment is copious irrigation. It is not unusual to use more than 2 L of irrigation fluid to remove all visible cyst contents. Using warmed irrigation fluid will decrease the risk of hypothermia that is associated with large volumes of cool irrigation fluid. In the event that the mass is subsequently determined to be malignant, the gynecologic oncologist should be made aware that spillage has occurred. Large Cysts
Some ovarian cysts may be too large to fit into a retrieval bag before drainage. In this situation, drainage of the cyst before laparoscopic removal is necessary. Because the risk of malignancy increases with cyst size, the importance of minimizing intraperitoneal spill becomes even greater. Informed patient consent concerning this unavoidable risk is essential.
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A
B Figure 50-5 A, B, An endometrioma cyst wall is being dissected off the ovary. Note that most of the cortex is left intact. C, Bipolar coagulation is used for hemostasis and for destruction of any cystic tissue that was not removed.
C
Intraperitoneal aspiration of a large ovarian cyst can be performed with either a laparoscopic aspiration needle or the suction– irrigation cannulae placed directly through the abdominal wall. Intraperitoneal spillage can be minimized (but not completely prevented) by placing a pursestring suture around the aspiration site before puncture or by placing an endoligature over the drainage site after cyst decompression. After the ovarian cyst has been decompressed, it can be removed from the abdomen.
(Fig. 50-5A and B). Bleeding is common from the dissection bed, and bipolar cautery can be used to cauterize bleeding sites (see Fig. 50-5C). Excessive use of cautery can cause ovarian damage. The cyst wall is then placed in an endoscopic retrieval bag and extracted through a port incision. The specimen should be sent for microscopic evaluation, because malignancies can sometimes be indistinguishable from endometriomas. Excessive removal of ovarian tissue will diminish ovarian reserve.
Laparoscopic Endometrioma Resection Removal of an endometrioma is referred to as cystectomy, but the procedure is markedly different from that used for other ovarian cysts. Endometrioma cyst walls are usually densely adherent to the overlying ovarian tissue. This makes it difficult or impossible to find a surgical plane in many patients, and removing an endometrioma cyst wall intact is rarely possible. The first step in removal of an endometrioma is mobilization of the ovary from any adhesions to the pelvic sidewall or adjacent organs. Many endometriomas will rupture at this point and exude thick “chocolate” fluid. If the cyst remains intact, it will often rupture as the ovarian epithelium covering the cyst is incised. The edge of the cyst wall is separated from the ovarian tissue and is stripped using a combination of blunt and sharp dissection
CONCLUSION Laparoscopy has become the principal means to assess and manage low-risk pelvic masses in women. The laparoscopic approach has distinct advantages over laparotomy, including cost and patient comfort and recovery, and has been shown to be safe. The major concern about the laparoscopic approach is the risk of inadvertent intraperitoneal spillage of a gynecologic malignancy. The risk of this can be minimized by appropriate patient selection and careful surgical technique. Should a harmless-appearing cyst prove to be malignant, prompt and appropriate surgical management with the aid of a gynecologic oncologist is important to optimize long-term outcome.
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PEARLS ●
●
Most cysts in reproductive-age women are functional and require observation only. Most persistent cysts in reproductive-age women are benign and can be treated by laparoscopy with simple removal of the cyst.
●
●
● ●
Appropriate preoperative evaluation will minimize the inadvertent treatment of ovarian malignancies by laparoscopy. An attempt should be made to remove the cyst without rupture. The cyst should then be placed into a retrieval bag. Copious irrigation is required if rupture occurs. It is usually not necessary to suture the ovarian defect.
REFERENCES
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1. Majeed AW, Troy G, Nicholl JP, et al: Randomised, prospective, singleblind comparison of laparoscopic versus small-incision cholecystectomy. Lancet 347:989–994, 1996. 2. Guerriero S, Alcazar JL, Ajossa S, et al: Comparison of conventional color Doppler imaging and power Doppler imaging for the diagnosis of ovarian cancer: Results of a European study. Gynecol Oncol 83:299–304, 2001. 3. Havrilesky LJ, Peterson BL, Dryden DK, et al: Predictors of clinical outcomes in the laparoscopic management of adnexal masses. Obstet Gynecol 102:243–251, 2003. 4. Attaran M, Falcone T, Goldberg J: Endometriosis: Still tough to diagnose and treat. Cleve Clin J Med 69:647–653, 2002. 5. Norris HJ, Jensen RD: Relative frequency of ovarian neoplasms in children and adolescents. Cancer 30:713–719, 1972. 6. Koonings PP, Campbell K, Mishell DR Jr., Grimes DA: Relative frequency of primary ovarian neoplasms: A 10-year review. Obstet Gynecol 74:921–926, 1989 7. Huss M, Lafay-Pillet MC, Lecuru F, et al: [Granulomatous peritonitis after laparoscopic surgery of an ovarian dermoid cyst. Diagnosis, management, prevention: A case report]. J Gynecol Obstet Biol Reprod (Paris) 25:365–372, 1996. 8. Chen L, Nelson SD, Berek JS: Recurrent mature cystic teratoma presenting as a perihepatic mass. Obstet Gynecol 94:856, 1999. 9. Lin P, Falcone T, Tulandi T: Excision of ovarian dermoid cyst by laparoscopy and by laparotomy. Am J Obstet Gynecol 173:769–771, 1995. 10. Nezhat CR, Kalyoncu S, Nezhat CH, et al: Laparoscopic management of ovarian dermoid cysts: Ten years’ experience. JSLS 3:179–184, 1999. 11. Templeman CL, Hertweck SP, Scheetz JP, et al: The management of mature cystic teratomas in children and adolescents: A retrospective analysis. Hum Reprod 15:2669–2672, 2000. 12. Padilla LA, Radosevich DM, Milad MP: Accuracy of the pelvic examination in detecting adnexal masses. Obstet Gynecol 96:593–598, 2000. 13. Schutter EM, Kenemans P, Sohn C, et al: Diagnostic value of pelvic examination, ultrasound, and serum CA 125 in postmenopausal women with a pelvic mass. An international multicenter study. Cancer 74:1398–1406, 1994. 14. Guerriero S, Mallarini G, Ajossa S, et al: Transvaginal ultrasound and computed tomography combined with clinical parameters and CA-125 determinations in the differential diagnosis of persistent ovarian cysts in premenopausal women. Ultrasound Obstet Gynecol 9:339–343, 1997. 15. Andersen ES, Knudsen A, Rix P, Johansen B: Risk of malignancy index in the preoperative evaluation of patients with adnexal masses. Gynecol Oncol 90:109–112, 2003. 16. Finkler NJ, Benacerraf B, Lavin PT, et al: Comparison of serum CA 125, clinical impression, and ultrasound in the preoperative evaluation of ovarian masses. Obstet Gynecol 72:659–664, 1988. 17. Granberg S, Wikland M, Jansson I: Macroscopic characterization of ovarian tumors and the relation to the histological diagnosis: Criteria to be used for ultrasound evaluation. Gynecol Oncol 35:139–144, 1989. 18. Guerriero S, Ajossa S, Garau N, et al: Ultrasonography and color Doppler-based triage for adnexal masses to provide the most appropriate surgical approach. Am J Obstet Gynecol 192:401–406, 2005. 19. Davies AP, Jacobs I, Woolas R, et al: The adnexal mass: Benign or malignant? Evaluation of a risk of malignancy index. BJOG 100:927–931, 1993.
20. Strigini FA, Gadducci A, Del Bravo B, et al: Differential diagnosis of adnexal masses with transvaginal sonography, color flow imaging, and serum CA 125 assay in pre- and postmenopausal women. Gynecol Oncol 61:68–72, 1996. 21. Predanic M, Vlahos N, Pennisi JA, et al: Color and pulsed Doppler sonography, gray-scale imaging, and serum CA 125 in the assessment of adnexal disease. Obstet Gynecol 88:283–288, 1996. 22. Roman LD, Muderspach LI, Stein SM, et al: Pelvic examination, tumor marker level, and gray-scale and Doppler sonography in the prediction of pelvic cancer. Obstet Gynecol 89:493–500, 1997. 23. Alcazar JL, Jurado M: Using a logistic model to predict malignancy of adnexal masses based on menopausal status, ultrasound morphology, and color Doppler findings. Gynecol Oncol 69:146–150, 1998. 24. Guerriero S, Ajossa S, Risalvato A, et al: Diagnosis of adnexal malignancies by using color Doppler energy imaging as a secondary test in persistent masses. Ultrasound Obstet Gynecol 11:277–282, 1998. 25. Alcazar JL, Errasti T, Zornoza A, et al: Transvaginal color Doppler ultrasonography and CA-125 in suspicious adnexal masses. Int J Gynaecol Obstet 66:255–261, 1999. 26. Kobal B, Rakar S, Ribic-Pucelj M, et al: Pretreatment evaluation of adnexal tumors predicting ovarian cancer. Int J Gynecol Cancer 9:481–486, 1999. 27. Mol BW, Boll D, De Kanter M, et al: Distinguishing the benign and malignant adnexal mass: An external validation of prognostic models. Gynecol Oncol 80:162–167, 2001. 28. Mancuso A, De Vivo A, Triolo O, Irato S: The role of transvaginal ultrasonography and serum CA 125 assay combined with age and hormonal state in the differential diagnosis of pelvic masses. Eur J Gynaecol Oncol 25:207–210, 2004. 29. ACOG: The role of the generalist obstetrician-gynecologist in the early detection of ovarian cancer. ACOG Committee Opinion no. 280, December 2002. Obstet Gynecol 100:1413–1416, 2002. 30. Im SS, Gordon AN, Buttin BM, et al: Validation of referral guidelines for women with pelvic masses. Obstet Gynecol 105:35–41, 2005. 31. Gal D, Lind L, Lovecchio JL, Kohn N: Comparative study of laparoscopy vs. laparotomy for adnexal surgery: Efficacy, safety, and cyst rupture. J Gynecol Surg 11:153–158, 1995. 32. Vergote I, De Brabanter J, Fyles A, et al: Prognostic importance of degree of differentiation and cyst rupture in stage I invasive epithelial ovarian carcinoma. Lancet 357:176–182, 2001. 33. Sainz de la Cuesta R, Goff BA, Fuller AF Jr, et al: Prognostic importance of intraoperative rupture of malignant ovarian epithelial neoplasms. Obstet Gynecol 84:1–7, 1994. 34. Kodama S, Tanaka K, Tokunaga A, et al: Multivariate analysis of prognostic factors in patients with ovarian cancer stage I and II. Int J Gynaecol Obstet 56:147–153, 1997. 35. Dembo AJ, Davy M, Stenwig AE, et al: Prognostic factors in patients with stage I epithelial ovarian cancer. Obstet Gynecol 75:263–273, 1990. 36. Ahmed FY, Wiltshaw E, A’Hern RP, et al: Natural history and prognosis of untreated stage I epithelial ovarian carcinoma. J Clin Oncol 14:2968–2975, 1996. 37. Sjovall K, Nilsson B, Einhorn N: Different types of rupture of the tumor capsule and the impact on survival in early ovarian carcinoma. Int J Gynecol Cancer 4:333–336, 1994. 38. Mizuno M, Kikkawa F, Shibata K, et al: Long-term prognosis of stage I ovarian carcinoma. Prognostic importance of intraoperative rupture. Oncology 65:29–36, 2003.
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41. Boriboonhirunsarn D, Sermboon A: Accuracy of frozen section in the diagnosis of malignant ovarian tumor. J Obstet Gynaecol Res 30:394–399, 2004. 42. Cotran RS, Kumar V, Collins T, Robbins SL: Robbins Pathologic Basis of Disease. Philadelphia: W.B. Saunders Company, 1999.
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Surgical Techniques for Management of Anomalies of the Müllerian Ducts and External Genitalia Marjan Attaran, Gita Gidwani, and Jonathan Ross
INTRODUCTION Malformations of the müllerian ducts and the external genitalia can have significant impact on both reproductive potential and sexual function. When a patient presents with such an abnormality, it is important to put significant thought and time into determining the correct diagnosis and subsequent treatment. This is particularly true for surgical management of external genitalia anomalies, where consequences, in terms of gender assignment and later sexual function, remain largely uncertain. This chapter begins with a review of the diagnostic and presurgical evaluation of these anomalies. The majority of the chapter deals with basic principles of surgical techniques used to correct these anomalies. The pathophysiology of genital anomalies is reviewed in Chapter 12.
CLASSIFICATION The classification of müllerian anomalies helps with both diagnosis and the comparison of outcomes after various modes of management. However, there is no single classification that encompasses all anomalies that have been reported in the literature.1–3 On the basis of pathophysiology, müllerian anomalies can be broadly classified into problems according to the developmental mechanism whose failure gave rise to the malformation. Anomalies can usually be classified as being related to (1) agenesis, (2) vertical fusion defects, or (3) lateral fusion defects.4 Agenesis of the uterus and vagina are relatively common abnormalities. Agenesis of other müllerian structures is extremely rare. Vertical fusion defects are usually the result of abnormal canalization of the vaginal plate and result in defects such as a transverse vaginal septum and imperforate hymen. Lateral fusion defects can be symmetrical or asymmetrical and include septum of the uterus and vagina, as well as unicornuate and bicornuate uteri and related abnormalities. The most accepted classification of uterine anomalies, published by the American Society for Reproductive Medicine (ASRM), places uterine anomalies into distinct groups based on anatomic configuration (Table 51-1).5 Because vaginal anomalies are not included in this classification, they must be described along with the uterine anomaly. This classification does not give insight into pathophysiology, but it is an effective way to communicate observations for purposes of treatment and prognosis.
MÜLLERIAN AGENESIS Clinical Presentation Müllerian agenesis (i.e., Mayer-Rokitansky-Küster-Hauser syndrome) was first described in 1829. Its incidence is reported to be 1 in every 5000 newborn females.6 Because the vagina and associated uterine structures do not develop with this disorder, it is a ASRM Class IA müllerian anomaly. Patients typically present during their adolescent years with complaint of primary amenorrhea. As a cause of primary amenorrhea, müllerian agenesis is second only to gonadal dysgenesis.7 Patients with müllerian agenesis will present with normal onset of puberty and appropriate secondary sexual characteristics, but apparently delayed menarche. They do not complain of cyclic pelvic pain like patients with obstructive müllerian anomalies. The external genitalia appear completely normal, with normal pubic hair growth and normal-size labia minora, which is in contrast to patients with complete androgen insensitivity syndrome. Hymeneal fringes may be evident, but the vaginal opening is absent. No pelvic masses suggestive of hematocolpos will be evident, which is in contrast to cases of complete transverse septum.
Table 51-1 ASRM Classification of Müllerian Anomalies I. Hypoplasia/Agenesis a. Vaginal b. Cervical c. Fundal d. Tubal e. Combined II. Unicornuate a. Communicating b. Noncommunicating c. No cavity d. No horn III. Didelphus IV. Bicornuate a. Complete b. Partial V. Septate a. Complete b. Partial VI. Arcuate VII. DES-related
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Section 7 Reproductive Surgery Because these patients have a 46,XX karyotype, normal ovaries will be present in the pelvis. Ovulation can be documented as a shift in basal body temperature. These patients’ hormonal levels are normal, and their cycle length based on hormonal studies varies from 30 to 34 days.8 In addition they may experience the monthly pain (mittelschmertz) that is indicative of ovulation.
Associated Anomalies Some but not all anomalies described can be extrapolated from the embryology.9–12 Hearing difficulties have been reported in patients with müllerian agenesis.10,11 A higher rate of auditory defects have been noted in general in patients with müllerian anomalies compared to those with normal müllerian structures.12 Müllerian agenesis is associated with renal and skeletal system anomalies. Renal abnormalities are noted in 40% of these patients. These include complete agenesis of a kidney, malposition of a kidney, and changes in renal structure.13 Skeletal abnormalities are noted in 12% of patients and include primarily spine defects followed by limb and rib defects.14 Patients with müllerian agenesis should be actively assessed for these associated anomalies.
Etiology The etiology of müllerian agenesis remains unknown. It appears to be influenced by multifactorial inheritance, and rare familial cases have been reported. It does not appear to be transmitted in an autosomal dominant inheritance pattern, because none of the female offspring of women with müllerian agenesis (born via in vitro fertilization [IVF] and surrogacy) have shown evidence of vaginal agenesis.9
Diagnosis Imaging
The diagnosis of müllerian agenesis is confirmed via imaging techniques. Abdominal ultrasonography will demonstrate the lack of uterus and existence of ovaries. The presence of a midline mass consistent with a blood collection usually indicates an obstructive müllerian anomaly. The distinction between müllerian agenesis and obstruction is extremely important, because an incorrect diagnosis can seriously jeopardize appropriate management. With the advent of magnetic resonance imaging (MRI), laparoscopy is no longer considered necessary to make this diagnosis. Typical findings in the pelvis include normal ovaries and fallopian tubes, and usually small müllerian remnants attached to the proximal portion of the fallopian tubes, that may be solid or have functioning endometrial tissue. Direct communication with the radiologist about the differential diagnosis before imaging studies is important. On occasion, the unsuspecting radiologist may interpret the small uterine remnants as a uterus. Careful attention to the very small dimensions of this structure will alert the physician to this possibility.
be reassured that her external genitalia appear normal and that she will be able to have a normal sex life after the creation of a normally functioning vagina. Although usually not voiced, the inability to subsequently bear children is a major disappointment to teenagers. Fortunately, with assisted reproductive technology procedures, including IVF and surrogacy, having her own genetic child will be an option for many of these young women.
CREATION OF A NEOVAGINA The first goal of treatment of müllerian agenesis is creation of a functional vagina to allow intercourse. Frank first proposed vaginal dilation with use of a dilator as a means of creating a neovagina in 1938.15 However, the surgical techniques of vaginoplasty remained the preferred methods for many years. The success of any technique depends in large part on the emotional maturity of the patient. Pretreatment counseling and continued support during treatment is important.
Vaginal Dilation The simplicity and ease of vaginal dilation and its significantly lower complication rate than surgical techniques dictates its use as initial form of therapy for most patients with müllerian agenesis. The American College of Obstetricians and Gynecologists recently released a committee opinion that recommends nonsurgical management of müllerian agenesis as the first mode of treatment.16 Frank’s technique of dilation involves actively placing pressure with the dilators against the vaginal dimple (Fig. 51-1). The patient is not only in an awkward position, but the hand applying the pressure can also become tired. In 1981, Ingram proposed the concept of passive dilation, where pressure is placed on the dilator by sitting on a bicycle seat.17 Roberts reported a success rate of 92% in women who dilated the vagina via the Ingram technique for 20 minutes three times a day.18 The average time to creation of a functional vagina was 11 months. This series demonstrated that an initial dimple less than 0.5 cm was all that was necessary to achieve adequate dilation. Interestingly, failure of this technique was not related to length of vaginal dimple but rather was more closely associated
Explaining the Diagnosis to the Patient
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The diagnosis, usually made in early adolescence, must be explained to the patient with great sensitivity. At a time when being like her peers is extremely important, knowledge of this diagnosis can be psychologically devastating. Each patient must
Figure 51-1
Examples of vaginal dilators of different sizes.
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Chapter 51 Surgical Management of the Müllerian Ducts and External Genitalia on the patient’s desires. The median age of starting treatment is 17 years.22 For appropriately selected motivated patients, the reported success rates are as high as 90%.23
Anterior abdominal wall
Vecchietti Procedure Bladder
Posterior direction
Peritoneal cavity
Giuseppe Vecchietti described this method of creating a neovagina in 1965.24 Similar to vaginal dilation, this method avoids the use of a graft. The Vecchietti procedure is a one-step procedure in which a neovagina is created in 7 days by continuous pressure on the vaginal dimple using an acrylic olive connected by retroperitoneal sutures to a spring-tension device on the lower abdomen. Although the original description of the Vecchietti procedure utilized laparotomy, this technique is currently performed laparoscopically.25,26 Procedure
Rectum
Figure 51-2 Schematic drawing of angle of dilator placement. The patient is viewed in lithotomy position and the axis is directed away from the bladder.
with the patient’s youth. Failure of this technique was more common in patients younger than age 18. Procedure
When the patient expresses a desire to proceed with therapy, she is shown the exact location of her vaginal dimple. The axis of dilator placement is also demonstrated (Fig. 51-2). The process is initiated by placement of the smallest dilator against the dimple. Pressure is kept on the distal aspect of the dilator by sitting on a stool while leaning slightly forward. When the dilator fits comfortably she moves to the next size dilator. The patient is instructed to use this technique a minimum of 20 minutes a day, two to three times a day. In motivated patients, a functional vagina can be created in as short as 12 weeks. Counseling and psychological support is integral to successful treatment.19–21 Patients are requested to return to the office frequently to monitor their progress, provide guidance, and have an opportunity to answer questions. Intercourse may be attempted when the largest dilator fits comfortably. Multiple types of graduated dilators, made of various materials, are present on the market. None have been found superior to the others. Patients may stop and reinitiate the dilation at any time without any negative long-term sequelae. Although most patients appear interested in initiating this therapy the summer before college when they are mature enough and motivated to create the vagina, the timing of therapy is purely dependent
The first step in this procedure is to use a sharp ligature carrier (similar to a Stamey needle) to insert one end of a suture through the retrohymeneal dimple into the peritoneal cavity between the bladder and the rectum under laparoscopic guidance. The other end of this number 2 polyglycolic acid suture is placed through a 3-cm acrylic olive and likewise inserted through the dimple into the peritoneal cavity using the sharp ligature carrier. The next step is to use a curved blunt ligature carrier to burrow retroperitoneally from a lateral suprapubic laparoscopic port site to the peritoneal fold between the bladder and the uterine rudiment. One end of the olive suture is placed through the eye of this curved ligature carrier and pulled retroperitoneally back through the abdominal wall port site incision. This procedure is repeated on the opposite side with the other end of the suture. After the laparoscope is removed and the abdominal wall incisions are closed, the ends of the suture are attached to a suprapubic Vecchietti spring-traction device located externally on the abdomen.25 Postoperatively, constant traction is applied to the perineal olive by daily readjustment of the tension of the sutures and traction device. The neovagina lengthens by 1 to 2 cm per day, such that a 10- to 12-cm vagina is created in 7 to 9 days. After creation of the vagina, the olive (now located at the apex of the neovagina) is removed and the patient is sent home with a vaginal mold in place. After surgery, it is important to initiate regular sexual intercourse or routinely use dilators to maintain vaginal length. Vecchietti reported a series of more than 500 patients with a success rate of 100% and only nine complications, including one bladder and one rectal fistula.27 Several smaller studies have subsequently been reported by other surgeons with similar outcomes.28,29 A 3-year follow-up study assessed the functional and psychological outcome in five patients.30 All five subjects reported having a functioning vagina allowing satisfactory intercourse and improvement in general well-being.
Vaginoplasty Techniques The traditional surgical management of vaginal agenesis is to create a vaginal space followed by placement of a lining to prevent stenosis. Multiple tissues and at least one manmade material have been used to line this cavity with varying degrees of success in preventing subsequent stenosis of the neovagina (Table 51-2).
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Section 7 Reproductive Surgery Table 51-2 Surgical Methods of Creating a Neovagina Dissection of a perineal space Split-thickness skin graft (McIndoe operation) Full-thickness skin graft Peritoneum (Davydov procedure) Amnion Muscle and skin flap Adhesion barriers Tissue expansion Bowel vaginoplasty Sigmoid colon Vulvovaginal pouch Williams vaginoplasty Traction on retrohymeneal fovea Vecchietti procedure
Figure 51-4 The initial transverse cut was made on the fibrous tissue and an initial space developed.
Figure 51-3
Skin graft is sutured around a mold.
McIndoe Procedure
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The most widely used surgical technique for creation of a neovagina is the McIndoe operation. The first step of the procedure is obtaining the split-thickness skin graft. The plastic surgery team typically acquires the skin graft from the buttock area, a location usually covered by clothing. The patient is placed in the prone position and the site is cleansed with an antiseptic solution and then soaked with an epinephrine saline gauze to allow vasoconstriction of small punctate bleeding sites. Mineral oil is applied to the donor site and the skin is held taut while the electrodermatome device is used to obtain a thick split-thickness skin graft. The skin graft should be 0.015 to 0.018 inch thick. After application of antiseptic solution, the donor site is covered with Op-Site, which is fixed in place by several stitches. Within 2 to 3 weeks the area heals with acceptable scarring. The skin graft is placed through a 1:5 ratio skin mesher. The purpose of meshing the skin is not to stretch it but rather to allow escape of any underlying blood clots or serous fluids. This skin graft is sutured around the mold with 4-0 absorbable suture (Fig. 51-3). The mold is covered completely, because any uncovered sites, whether due to lack of enough tissue or a gaping hole in the line of suture, tend to result in the formation of granulation tissue. Thus great care must be taken to obtain a sufficient amount of graft for this procedure.
The patient is placed in the dorsolithotomy position. A transverse incision is made in the vaginal vestibule, between the rectum and urethral openings (Fig. 51-4). In a patient who has not had prior surgery or radiation in the area, areolar tissue is now encountered. This tissue is easily dissected with either fingers or a Hagar dilator on either side of a median raphe (Fig. 51-5). The dissection is continued for at least the length of the mold without entering the peritoneal cavity. By cutting the median raphe, the two channels are then connected. If the dissection is performed in this manner, minimal bleeding is encountered. Any bleeding sites must be controlled meticulously to avoid lifting of the graft from the newly created vaginal wall and subsequent nonadherence and necrosis. After creation of the vaginal space, the mold covered with the skin graft is placed inside the cavity (Fig. 51-6). At the introitus, the skin graft is attached with several separate 3-0 absorbable stitches. To hold the mold in place, several loose nonreactive sutures such as 2-0 silk are used to approximate the labia minor in the midline. During the ensuing week, the patient is maintained on bed rest, broad-spectrum antibiotics, a low-residue diet, and an agent to decrease bowel motility. She also has an indwelling urinary catheter in place. On return to the operating room in 1 week, the mold is carefully removed. The vaginal cavity is irrigated with warm saline solution and the graft site is carefully assessed for any signs of necrosis or underlying hematoma. Another soft mold is then reinserted and kept in place for the next 3 months except during defecation and urination. Nighttime usage of the mold is recommended for the next 6 months. To prevent contracture of the vagina, the patient is instructed to reinsert the mold during extended times of sexual inactivity. Difficulty in dissecting the neovagina and increased probability of bleeding and fistula formation is encountered in the patient with a prior surgical procedure. Other problems that may be
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Figure 51-5 Placement of Hagar dilator to create space for the graft. The direction of the Hagar dilators is posterior.
Figure 51-6 The mold with the graft is placed in the space. Notice that the space to be created must accommodate the mold completely.
Figure 51-7
Hard glass mold.
Figure 51-8
Adjustable vaginal mold (Mentor, Minneapolis).
encountered include narrow subpubic arch, strong levators, shorter perineum, prior hymenectomy, and congenitally deep cul-de-sac.31 Because of concern regarding tissue necrosis from mold pressure and subsequent fistula formation, both rigid and soft molds have been used for this procedure (Figs. 51-7 and 51-8). Theoretically, soft molds decrease the risk of fistula formation that can result from avascular necrosis. A soft mold can be created by covering a foam rubber block with a condom.32 The foam is able to expand and fit the neovaginal space, thereby providing equal pressure throughout the canal. However, a report on the use of a rigid mold on 201 patients who underwent the McIndoe operation demonstrated a fistula formation rate of less than 1%.33 There is no study comparing the outcomes of soft versus rigid molds in this operation. Typically a rigid mold is used initially, but the patient is sent home with a soft mold in place. An 80% success rate has been reported with this procedure.34 Because success rates are highest in those patients that have not undergone prior vaginoplasty, patients must be counseled extensively before surgery regarding the need for prolonged use of the mold. Indeed, part of the presurgical assessment involves determination of patient maturity and motivation concerning the use of dilators. Lack of compliance with postoperative use of dilators will lead to contracture and diminishment of vaginal length.
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Section 7 Reproductive Surgery Surgical complications include postoperative infection and hemorrhage, failure of graft and formation of granulation tissue, and fistula formation. In general the incidence of complications are low: a rectal perforation rate of 1%, graft infection in 4%, and graft site infection of 5.5%.33 In a review of 50 patients, 2 rectovaginal fistulas and 1 graft failure were reported.31 Five patients required an additional operative procedure. Eighty-five percent of these patients considered their surgery to be a success. Long-term data on the McIndoe procedure, although limited, consistently indicate an improvement in quality of life. In a series of 44 patients who underwent a surgical procedure to create the vagina, 82% achieved a functional satisfactory postoperative result.35 Vaginal length varied from 3.5 to 15 cm. In another long-term study of women who underwent a McIndoe procedure, 79% of the patients reported improved quality of life, 91% remained sexually active, and 75% regularly achieved orgasm.36 The newly created vagina must be inspected at the time of the yearly pelvic examination and regular pap tests. Hair growth has been reported to be a problem with some skin grafts. Transformation to squamous cell carcinoma from skin graft has been described.37,38
of clothlike oxidized regenerated cellulose are wrapped around the mold and placed in the vagina in a manner similar to the McIndoe. The neovaginal space must be free of any bleeding. Epithelialization is noted to occur within 3 to 6 months. Small areas of granulation tissue may be seen at the apex of the vagina and resolve after application of silver nitrate. Average vaginal depth ranges from 6 to 12 cm. Continuous use of the mold is encouraged until complete epithelilization has occurred. A case series assessed the outcome of this technique on 10 patients with vaginal agenesis.46 Complete squamous epithelialization was noted within 1 to 4 months. When compared to a normal vagina, fern formation was noted and the vaginal pH was always acidic. However, none of the women complained of vaginal dryness or foul-smelling discharge. Patients who were sexually active did not report any problems. The advantages of use of oxidized regenerated cellulose include avoidance of any scars, readily available product, and low expense. In addition, the surgical procedure is simplified into a one-stage procedure. Although the reported data appear encouraging, confirmatory studies are required before use of oxidized regenerated cellulose can be recommended without any reservations. Amnion Lining
Peritoneal Graft: Davydov Procedure
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Amnion has also been used to line the neovagina cavity.47 Advantages include lack of a graft site, potential antibacterial effect, and lack of expression of histocompatibility antigens.48,49 Eight to 10 weeks after placement of amnion into the vaginal canal, the resulting epithelium was found to be “identical” to normal vaginal epithelium.50 However, concern about transmission of an infection with use of amnion has limited its use in the United States.
Use of the peritoneum to line the newly created vaginal space was popularized by Davydov, a Russian gynecologist, and first described by Rothman in the United States in 1972.39–41 In his original description, a laparotomy is performed after creation of the vaginal space, as described with the McIndoe operation. A cut is made on the peritoneum overlying the new vagina. Long sutures are applied to the anterior posterior and lateral sides of this peritoneum. The sutures are then pulled down through the vaginal space, thus pulling the peritoneum to the introitus. The edge of the peritoneum is then stitched to the mucosa of the introitus. Closing the peritoneum on the abdominal side then forms the top of the vagina. Several investigators have also described the laparoscopic modification of this procedure.42–44 This procedure may have several advantages compared to the traditional McIndoe. Contrary to skin grafts that leave visible scarring at the donor site, there is no outward sign of using a graft in the Davydov procedure. There appears to be no danger of lack of graft takes and no problem with hair growth. In Davydov’s first reported series, sexual intercourse was initiated within several weeks of surgery in all but one of his 30 patients. On follow-up, the length of the vagina was noted to be 8 to 11 cm. In a series of 18 patients who underwent the laparoscopic modification of this procedure, 85% reported being sexually satisfied during an 8- to 40-month follow-up. Although there was one report of a rectovaginal fistula 18 months after the surgery, there was no evidence of vault prolapse or enterocele formation. Minor granulation tissue was noted at the vaginal cuff, but the vault was primarily covered with squamous epithelium tissue.
These approaches are not procedures of choice for women with vaginal agenesis. However, they may be used for those who require vaginal reconstruction after exposure to radiation or multiple surgical procedures. The advantage of using a fullthickness skin flap is that it avoids the problem of contracture encountered with split-thickness grafts. The use of gracilis myocutaneous flaps and rectus abdominis myocutaneous flaps for vaginal reconstruction has been reported.51,52 This approach has been associated with a conspicuous scar and a higher failure rate. Wee and Joseph in Singapore designed flaps that maintained good blood supply and innervation.53 Known as a pudendal–thigh flap vaginoplasty, this technique has been particularly successful in patients with vulvar anomalies.54 In one study of patients with müllerian agenesis, 100% success in creating a functional vagina was reported.55 The patient’s own labia majora and labia minora have also been used to create a vagina.56 Tissue expansion has also been advocated to create labiovaginal flaps, which are then used to line the neovagina.57,58 Other modifications of this procedure have been reported.59,60
Adhesion Barrier Lining
Bowel Vaginoplasty
Jackson first described the use of an adhesion barrier to line the neovagina in 1994.45 Oxidized regenerated cellulose (Interceed; Johnson and Johnson Patient Care Inc, New Brunswick, N.J.) forms a gelatinous barrier on raw surfaces and thus prevents adhesion formation. After creation of the vaginal space, sheets
This is not a procedure of choice in women with vaginal agenesis. For this procedure, also known as a colocolpopoiesis, a portion of large bowel with its preserved vascular pedicle is sutured into the neovagina. In recent years, sigmoid colon use has been recommended.
Muscle and Skin Flap
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Chapter 51 Surgical Management of the Müllerian Ducts and External Genitalia Figure 51-9 Magnetic resonance image of functioning rudimentary bulbs.
metrial shedding, and development of endometriosis has been reported in these patients. Symptomatic müllerian bulbs should be removed either via laparotomy or laparoscopy.
Surgical Technique The procedure is started by placing traction on the ipsilateral uterine bulb. The round ligament is grasped, cut, and the peritoneum incised anteriorly, thereby creating a bladder flap. The retroperitoneal space is entered, the ureters identified, and the utero-ovarian ligaments transected. The dissection continues with identification and coagulation of the uterine arteries. Finally, the uterine remnants and the fibrous tissue connecting them are incised.
CERVICAL AGENESIS Figure 51-10
Pathologic specimen of the extirpated rudimentary bulbs.
Continuous use of dilators is not considered necessary, although constriction has been noted when ilium has been used. Success rates of up to 90% have been reported. Reported complications include profuse vaginal discharge, prolapse, introital stenosis, bowel obstruction, and colitis.61,62 Finally there is a report of a mucinous adenocarcinoma arising in a neovagina lined with the sigmoid colon.63 A laparoscopic modification of this procedure has also been described.64,65 Given the increased complication rates, it seems appropriate to reserve this treatment modality for complex situations where a prior vaginoplasty technique has failed or when there are multiple urogenital malformations.
OBSTRUCTED RUDIMENTARY UTERINE BULBS Patients with müllerian agenesis commonly have müllerian remnants noted on MRI or during a laparoscopy. The MRI has the added value of determining if any endometrial tissue exists within these remnants (Figs. 51-9 and 51-10). Patients with functional endometrial tissue may present after many asymptomatic years with cyclic pelvic pain secondary to monthly endo-
Cervical agenesis is a rare müllerian anomaly whose true incidence remains unknown despite many case reports in the literature.66 Various degrees of cervical abnormalities, ranging from dysgenesis to agenesis, have been described.67 The vagina may or may not be present in patients with cervical agenesis. In a series of 58 patients with cervical atresia, 48% had isolated congenital cervical atresia with a normal vagina.68 The rest of the patients had either a vaginal dimple or complete atresia.
Diagnosis Unlike some of the other müllerian anomalies, patients with cervical agenesis present very early in adolescence. Typically, patients present between ages 12 and 16 with a primary complaint of pelvic pain secondary to obstruction of flow from the uterus. Initially, the pain is cyclic, but it may evolve with time into continuous pain. It is not uncommon for such patients to have been evaluated by their pediatricians for other causes of abdominal pain. Although these girls have amenorrhea, this symptom fails to raise a red flag because the patients are so young at presentation that lack of menses is not concerning. Continuing menstruation in an obstructed uterus forms a hematometra, and possibly hematosalpinx, endometriosis, and adhesions in the pelvis (Figs. 51-11 and 51-12). Imaging of such a pelvis can easily lead to a misdiagnosis. Such patients have been taken to surgery for pain thought to be secondary to a pelvic mass, only to find that they have a congenital
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Section 7 Reproductive Surgery Management Pain Control
Figure 51-11
Schematic representation of cervical agenesis.
Pain control should be the first goal of treatment. Although analgesia may be required, severe pain will resolve within several days. Suppressive therapy is used to prevent further endometrial shedding until definitive surgery can be performed. Agents that are commonly used to achieve this suppression are continuous oral contraceptive pills, norethindrone acetate, depot-medroxyprogesterone acetate (DMPA), and gonadotropin-releasing hormone agonists or antagonists. Most adolescents are neither emotionally ready nor equipped to decide on a surgical course of action that may be as invasive as hysterectomy. Thus, if suppressive therapy with oral contraceptives or DMPA has provided pain relief, many may choose to hold off on definitive surgical therapy until they can fully understand the possible consequences. In addition, this alleviates the burden placed on parents to make a decision regarding their daughter’s reproductive future. Surgical Approach
Figure 51-12 Magnetic resonance image of cervical agenesis. The uterine cavity is distended with clots and no cervix is identified.
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anomaly. Although ultrasound may be helpful in looking for a cervix, one’s clinical suspicion must be communicated directly to the radiologist performing the procedure. MRI is very helpful in visualizing the cervix and can accurately determine its presence or absence.69–71 Patients with cervical agenesis who lack a vagina must be differentiated from those with a high obstructing vaginal septum. MRI is very helpful in making this differentiation by showing accumulation of blood in the upper vagina and a cervix in patients with a high transverse septum. Lack of a hematocolpos helps make the diagnosis of cervical agenesis or dysgenesis. Theoretically, MRI should detect absence of the cervix, but is unable to clearly differentiate among the various degrees of cervical dysgenesis.
There are no specific guidelines in the literature to determine the correct surgical procedure. It is clear, however, that each patient should be assessed individually. The definitive and safest treatment of cervical agenesis remains total abdominal hysterectomy. A hysterectomy would diminish continued physical pain and discomfort. In addition, with the advent of surrogate pregnancy, an early hysterectomy would potentially preserve more ovarian tissue, which may be used to achieve a pregnancy via surrogacy and IVF. On the other hand, it is a daunting decision to have a hysterectomy at a young age. The other surgical options for management of cervical dysgenesis are cervical canalization or uterovaginal anastomosis. There are many reports in the literature of cervical canalization and stent placement.72–74 Although success has been reported with establishment of menses, many patients will require reoperation secondary to fibrosis of the cervical tract and obstruction. In addition, pregnancy rates are very low. In a review of patients with cervical agenesis, 59% of those that underwent cervical canalization achieved normal menstruation. Four of the 23 who achieved cervical patency required multiple surgeries.68 The task is even more daunting if there is also a vaginal anomaly that requires reconstruction. There are several forms of cervical dysgenesis that are sometimes confused with agenesis.75 A hysterectomy may be considered in those patients with no evidence of a cervix, but canalization or uterovaginal anastomosis may be considered in those with a vagina and an obstructed cervix. Although preserving fertility is ultimately the goal of canalization procedures, sepsis and death have been reported subsequent to canalization.76 In addition, subsequent pregnancy rates are very low.73,77 The poor pregnancy rates may be attributed to several factors. Prolonged delay in diagnosis can lead to extensive endometriosis and scarring in the pelvis. Also, although canalization and stent placement may maintain an open pathway for menstruation, the lack of epithelization of the fistula not only increases the risk of fibrosis, but also may impede sperm migration into the uterus. The only pregnancy that was achieved in Rock’s series was one in whom a full-thickness skin graft was used in
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Chapter 51 Surgical Management of the Müllerian Ducts and External Genitalia Figure 51-13 The appearance of a bicornuate uterus at laparoscopy. Note the peritoneal band between the two horns.
the canalized area.75 More recently the use of bladder mucosa to line the newly created cervical canal was reported.72 After preoperative assessment and formation of the operative plan, the surgeon must be prepared to proceed with a concomitant vaginoplasty if indeed the patient suffers from vaginal atresia. The patient should have been preoperatively counseled regarding the need for prolonged use of a mold after surgery. Advances in artificial reproductive techniques have led to reports of pregnancies in patients with cervical agenesis. Thus, many patients are likely to choose effective continued endometrial suppression over a surgical solution in hopes of keeping a glimmer of reproductive hope. With the passage of time and attainment of adulthood, such patients may be better able to accept the diagnosis and its consequences.
UTERINE FUSION DEFECTS Uterine fusion defects include septate, bicornuate, and didelphic uteri. Patients with these isolated uterine anomalies are asymptomatic. The diagnosis is usually made during evaluation of infertility, recurrent pregnancy loss, or an obstetric complication. Correct diagnosis of these anomalies is of utmost importance, because their management varies significantly.78 The diagnosis is typically made based on evaluation of anatomy via imaging techniques, including ultrasonography, hysterosalpingography (HSG), and MRI or via laparoscopy and hysteroscopy. Although radiologic guidelines exist to differentiate these entities, the multitude varieties of these malformations can pose a significant challenge in making the correct diagnosis.
Septate Uterus Reproductive difficulties are encountered far more commonly in women with a septate uterus than any other uterine fusion defect. The septate uterus is associated with the highest spontaneous abortion rate of the uterine fusion defects. The management of uterine septum detected after an evaluation for recurrent pregnancy loss is hysteroscopic resection of the septum (see Chapter 43). However, the management of a septum found during an infertility investigation is less straightforward.78 Although the septum does not appear to cause infertility, the concern regarding possible spontaneous abortion after undergoing infertility treatment may be enough to justify hysteroscopic removal of the septum before infertility treatment. On a historical note, in the distant past a uterine septum was sometimes removed along with the midline section of the uterus via laparotomy using a Jones or Tompkins metroplasty procedure. These relatively extreme approaches have been completely supplanted by hysteroscopic septoplasty, described in Chapter 43.
Bicornuate Uterus The most frequently diagnosed uterine malformation is the bicornuate uterus (Fig. 51-13).79 This anomaly is usually discovered incidentally during an investigation for infertility or recurrent pregnancy loss. It is important to differentiate a bicornuate from a septate uterus. HSG alone cannot differentiate these entities, because this imaging approach cannot evaluate the external contour of the uterus. Laparoscopy was used primarily for this purpose in
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Section 7 Reproductive Surgery the recent past; modern imagining techniques, including ultrasonography and MRI, can adequately differentiate these two entities (see Chapter 31). Imaging criteria to differentiate septate and bicornuate uteri have been developed.80,81 A septate uterus has a flat or convex fundus or a fundal indentation less than 10 mm. The septum should be relatively thin, such that the angle between the medial borders of the hemicavities is smaller than 60 degrees. A bicornuate uterus has two distinct funduses with an intervening fundal indentation of at least 10 mm. In most cases, the angle between the medial borders of the hemicavities will be greater than 60 degrees. On MRI, a septate uterus will fail to show an intervening myometrium between the T2-hypointense septum that separates the endometrial cavities.80,81 In contrast, a bicornuate uterus will show two T2-hyperintense endometrial cavities, each with a junctional zone and myometrial band of intermediate signal intensity. Conception does not appear to be a problem in women with bicornuate uterus.78 However, higher rates of preterm delivery (19%) and spontaneous abortion (42%) have been reported.82 Uteroplacental insufficiency and cervical incompetence may play roles in the higher obstetric complications. Thus, the treatment options for bicornuate uterus may include Strassman metroplasty and cervical cerclage. Because the benefit of metroplasty has never been established in a controlled study, it is typically considered only after multiple pregnancy losses and complications.83 Surgical Technique: Strassman Metroplasty
The Strassmann metroplasty is the procedure of choice in the uncommon case where unification of a bicornuate uterus is indicated.13 Via laparotomy, a transverse incision is made across the fundus of the bicornuate uterus. The opened cavity is then repaired in an anteroposterior fashion. Because the subsequent length of gestation appears to increase after each pregnancy loss in patients with a bicornuate uterus (due to myometrial stretching or unknown factors), metroplasty is always the procedure of last resort.
Didelphic Uterus The didelphic uterus is defined as two completely separate uteri and cervices. It accounts for 10% of all uterine anomalies.79 On ultrasonography, the two bulbs of the uterus are distinctly noted and can be followed down to their individual cervices. Surgical correction is not indicated. In a long-term follow-up of 49 patients with didelphic uteri, 89% of those desiring pregnancy had at least one living child.84 The spontaneous miscarriage rate was 21%, and only one ectopic pregnancy occurred. The most common problem was preterm delivery, which occurred in 24% of pregnancies. Fortunately, only 7% of the infants weighed less than 1500 gm at birth. Breech presentation was noted in 51% of the infants, and thus the cesarean section rate is increased.
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Figure 51-14
Noncommunicating uterine horn seen at laparoscopy.
patient is unlikely to have severe dysmenorrhea. The diagnosis in these patients is usually made at the time of investigation for infertility, obstetric problems (including recurrent pregnancy loss), or at the time of cesarean section. In contrast, if a noncommunicating rudimentary horn is functioning, most patients will have severe dysmenorrhea unresponsive to medical therapy (Fig. 51-14).
Diagnosis Pelvic examination may reveal a deviated uterus or an adnexal mass. Ultrasonography will be consistent with a unicornuate uterus on one side, while the other side may be interpreted as a rudimentary horn, a pedunculated leiomyoma, or an ovarian endometrioma. HSG will show a unicornuate uterus and will often, but not always, demonstrate the presence of a communication with the rudimentary horn when present. In uncertain cases, an MRI is often useful in making a definitive diagnosis.
Management Management depends on whether the rudimentary horn is functional or communicating. A nonfunctioning, noncommunicating rudimentary horn does not need to be removed, as it will be asymptomatic and not put the patient at any risk. In contrast a functioning, noncommunicating rudimentary horn should be removed on diagnosis to alleviate the patient’s often severe dysmenorrhea and to avoid the risk of rupture, should a pregnancy occur in this horn.85 It would seem that a functioning, communicating rudimentary horn could be left in situ, since it is unlikely to be symptomatic for the patient. However, there is a risk of developing a pregnancy in such a horn, leading to subsequent rupture if undiagnosed.86 Therefore, surgical removal is recommended before attempting pregnancy.
UNICORNUATE UTERUS AND RUDIMENTARY HORN
Surgical Technique: Removal of a Rudimentary Horn
A unicornuate uterus may be associated with a communicating or noncommunicating rudimentary horn. In either case, patients will have monthly regular periods. If a rudimentary horn is communicating or noncommunicating but nonfunctioning, the
A rudimentary uterine horn can be removed via laparotomy or laparoscopy using similar techniques, depending on surgical experience.87 After gaining access to the pelvis, the round ligament of the rudimentary horn is identified, ligated, and divided. Access is gained into the retroperitoneal space, the ureter is identified,
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Chapter 51 Surgical Management of the Müllerian Ducts and External Genitalia and the bladder is dissected off the lower border of the rudimentary horn. The rudimentary horn should be removed together with the corresponding fallopian tube to avoid a future ectopic pregnancy in a blind residual tube via sperm transmigration. After disconnecting the tube from the mesosalpinx, the utero-ovarian ligament is transected so that the ovary can be spared. The rudimentary horn may share myometrial tissue with the unicornuate uterus or be attached by a band of fibrous tissue.87,88 In cases where the uterine horn is attached to the uterus with a fibrous band, the blood supply is found within this band. Coagulation and transection of the band is all that is required. In cases where the rudimentary horn is attached to the uterus via shared myometrium, the blood supply cannot be easily identified; thus the uterine artery ascending beneath the rudimentary horn should be identified and ligated. It may be difficult to find a plane of dissection between the horn and the uterus, but care must be taken to avoid entry into the cavity of the unicornuate uterus or compromising the integrity of the myometrial thickness. After this dissection, the myometrial defect should be carefully reapproximated with interrupted or continuous sutures to minimize the risk of uterine rupture during a subsequent pregnancy.
LONGITUDINAL VAGINAL SEPTUM A longitudinal vaginal septum can be either nonobstructing or obstructing. A nonobstructing vaginal septum is often asymptomatic and discovered at the time of a pelvic examination or childbirth. A woman with an obstructing vaginal septum often presents with increasingly severe dysmenorrhea and a unilateral vaginal mass.
The Nonobstructing Longitudinal Vaginal Septum Nonobstructing longitudinal vaginal septa account for 12% of the malformations of the vagina. Although most are asymptomatic, some patients complain of continued vaginal bleeding despite placement of a tampon, difficulty removing a tampon, or dyspareunia. These septa may be complete or partial and can exist in any portion of the vagina (Fig. 51-15). The communication can be extremely small and a septum can easily be missed during physical examination, especially if there is a dominant vaginal canal. Once the diagnosis is made, both the uterus and renal anatomy should be assessed for associated anomalies. In one study, 60% of patients with longitudinal vaginal septa were found to have a bicornuate uterus.89 Other investigators have noted a predominance of didelphic uteri in such cases.90 A longitudinal vaginal septum should be removed in patients with complaints of dyspareunia and those who desire to be able to effectively use a tampon. In cases of didelphic uteri, removal of the septum may be necessity to allow sufficient access to each cervix for Pap smears. Some obstetricians advocate removal of a longitudinal vaginal septum before delivery to avoid potential dystocia and laceration of the septum.89 The number of patients with vaginal septa who have had successful vaginal deliveries remains unknown. However, emergent resection of a vaginal septum at the time of delivery to resolve dystocia has been reported.91 It seems reasonable to remove a thick longitudinal septum before pregnancy or before delivery if discovered during pregnancy.
Figure 51-15
Nonobstructing longitudinal vaginal septum.
Surgical Technique
The goal of surgery is removal of a wedge of tissue without damaging the cervix, bladder, or rectum. A Foley catheter is placed in the bladder. Because longitudinal vaginal septa are well vascularized, the anterior border of the septum, followed by the posterior border, are removed using unipolar electrosurgery. Care must be taken not to remove the septum too close to the vaginal wall, because this will leave larger mucosa defects. The edges of these mucosal defects are reapproximated with 2-0 absorbable suture. Postoperative use of a vaginal mold is not necessary.
The Obstructing Longitudinal Vaginal Septum Women with an obstructing longitudinal septum usually present with normal-onset menarche and increasingly severe dysmenorrhea. These patients are most likely to have a didelphic uterus. One of the uteri has a patent outlet; the other is obstructed (Fig. 51-16).
Figure 51-16 An obstructing longitudinal septum usually presents as a bulge in the vagina.
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Transverse vaginal septum Figure 51-17
Placement of angiocath into the transverse septum.
If the obstruction is low in the vagina, eventually a bulge may be noted on examination of the lower canal. However, a higher obstruction may be completely missed with just visual inspection, which is frequently the case in an adolescent. Digital examination may reveal a tense bulge in the vaginal wall (Fig. 51-17). In many instances the bulge is found in the anterior portion of the vagina between the 12 o’clock and 3 o’clock positions or between the 9 o’clock and 12 o’clock positions due to the rotation of the two cervices. Ultrasonography of the pelvis will usually show a pelvic mass, which can be misleading unless a vaginal septum is considered in the differential diagnosis. MRI is the best imaging mode for definitively diagnosing this abnormality. Like other müllerian anomalies, a longitudinal vaginal septum is associated with renal abnormalities, including absent kidneys, pelvic kidneys, and double ureters.92 Some longitudinal septums will be found to be only partially obstructing and a small opening in the septum can be found during menses with close inspection. Symptoms may vary from irregular and prolonged bleeding to profuse vaginal discharge. Occasionally the pinpoint opening provides a pathway for organisms to access the obstructed vagina, leading to pelvic infection and pyocolpos. Physical examination is unlikely to reveal a tense bulge, but a slight fullness may sometimes be appreciated in the paravaginal area. Surgical Technique
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Accurate delineation of anatomy is a prerequisite for surgical excision of a noncommunicating longitudinal vaginal septum. The first step is to place a needle into the bulging vaginal wall to identify the correct plane of dissection. Once blood extrudes from the needle, the adjacent tissue is incised with electrocautery to gain access into the obstructed vagina. Allis clamps are placed on the edges of this incision and the cavity is assessed. When removing the medial border of this septum, care must be taken to avoid damaging the urethra and cervix. The septum should be removed in its entirety to allow easily access to the second cervix for Pap smears. The raw mucosal edges are approximated with 2-0 absorbable suture. Use of a vaginal mold
Figure 51-18
Angle of incision into septum.
after surgery is not necessary, because postresection stenosis is rare. In difficult cases, use of either a resectoscope or hysteroscope to remove a longitudinal vaginal septum has been described.93,94 The previously hidden cervix and obstructed vaginal canal will often appear abnormal. The cervix is usually flush with the vaginal fornix and often appears erythematous and glandular. Histologically, the obstructed vaginal canal and septum on its obstructed side will have columnar epithelium and glandular cypts.92 Some patients may complain of profuse vaginal discharge after removal of the septum. Metaplastic transformation of the vaginal mucosa to mature squamous epithelium can take many years. Simultaneous laparoscopy during removal of a vaginal septum is not recommended unless the diagnosis is unclear on MRI or imaging studies indicate concomitant pelvic masses. As in all cases of obstructive müllerian anomalies, endometriosis is frequently encountered, even if the septum is only partially obstucting.95,96 With the possible exception of endometriomas, excision of the endometriosis is not recommended because these lesions will regress after removal of the obstruction.95 The obstetric outcome of such patients is similar to that reported for patients with simple didelphic uterus. Pregnancy rates of 87% and live birth rates of 77% have been reported.92
TRANSVERSE VAGINAL SEPTUM The incidence of transverse vaginal septum appears to be between 1 in 21,000 to 1 in 72,000.67 A transverse vaginal septum may be located in the upper (46%), middle (40%), and lower (14%) third of the vagina.97,98 A transverse vaginal septum may be complete or incomplete and varies in thickness (Figs. 51-18 and 51-19).
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Figure 51-19 Reapproximation of distal and proximal vaginal mucosa after excision of the septum.
Presenting Symptoms Patients with a complete transverse vaginal septum generally present with a complaint of primary amenorrhea in early to midpuberty. Pelvic pain is a common, but not universal, presenting complaint. Patients with high transverse vaginal septa are most likely to experience pelvic pain, and the pain will manifest earlier than in patients with septa located lower in the vagina. This is believed to be secondary to decreased space for the hematocolpos that ensues after initiation of menses. Patients with an incomplete transverse vaginal septum may complain of profuse vaginal discharge, dyspareunia, inability to insert a tampon, or tearing during intercourse with resultant bleeding. If asymptomatic, it may not be discovered until a routine gynecologic examination. Very rarely a transverse vaginal septum may be detected in an infant or young child. In such instances, a mucocolpos can present as an abdominal mass.67 If large enough, this mass may cause ureteral obstruction with secondary hydronephrosis. Compression of the vena cava and cardiopulmonary failure has also been reported.
Diagnosis Manual and speculum examination provide the most important information for diagnosis of a transverse vaginal septum. If the septum is very low, a vaginal opening may not be appreciated on evaluation of the external genitalia. A low transverse vaginal septum can usually be differentiated from an imperforate hymen by visual inspection. By increasing intra-abdominal pressure and increasing the bulge of the imperforate hymen, the Valsalva maneuver may further assist in this differentiation. If an opening to the vagina is noted, a manual or speculum examination may reveal a higher location of the septum. A rectal examination is very helpful in detecting a hematocolpos, since the bulge is readily palpable. Transperineal and transabdominal ultrasonography can sometimes diagnose and determine the thickness of a transverse vaginal septum. However, in most cases an MRI of the pelvis will be required to differentiate a transverse vaginal septum from other müllerian anomalies such as cervical agenesis.
Figure 51-20 Complete transverse septum. Notice that there is no bulge with a Valsalva maneuver that would be seen with an imperforate hymen.
These patients should also be evaluated for associated anomalies, including aortic coarctation, atrial septal defects, urinary tract anomalies, and malformations of the lumbar spine.99
Surgical Technique Surgical removal of a transverse vaginal septum is recommended as soon as practical after diagnosis to avoid continued retrograde menstruation. Endometriosis is common in patients with a transverse vaginal septum. However, removal of endometriosis lesions is not recommended because relief of the obstruction leads to their spontaneous resolution. Delay in detection or treatment of a transverse vaginal septum may lead to impaired fertility secondary to irreversible pelvic adhesions, hematosalpinges, and endometriosis. In one long-term follow-up study of 19 patients with transverse septa, 47% became pregnant.99 However, a small study in Finland showed a significantly higher live birth rate in women who had undergone very early diagnosis and management of their transverse vaginal septa.100 The unfortunate consequence of very early surgical management is an increased rate of subsequent vaginal stenosis. This is most likely due to inconsistent use of vaginal dilators by young adolescents, which are a necessary part of treatment of a thick vaginal septum. An alternative to early surgery for very young patients is medical termination of monthly endometrial shedding using DMPA to postpone surgery.101 The young girl can be instructed to dilate the distal vagina to stretch the distal vaginal mucosa, potentially decreasing the need for a graft, and to prepare her for postoperative use of the dilator. The thickness and location of the septum will determine the best approach to surgery. Thin, low transverse vaginal septa are much easier to repair than thick, usually high septa. Surgical Technique: Thin Transverse Vaginal Septum
Transverse septa that are thin and low in the vagina can usually be excised without difficulty. If visually a slight bulge cannot be appreciated on examination, an angiocath needle is placed through the septum (Fig. 51-20). With return of thick blood
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Section 7 Reproductive Surgery During surgery, a bulge will not be seen in the presence of a thick transverse septum. The correct angle of dissection can be determined by inserting an angiocath needle into the hematocolpos under ultrasound guidance. In difficult cases, the septum can be approached transfundally via the uterus using laparoscopy and laparotomy.67 The dissection is carried out taking care to protect the bladder and rectum. A Foley catheter is placed into the bladder. As the loose areolar tissue is being dissected, the rectum is frequently examined to ensure the appropriate angle of dissection. If there is inadvertent entry into the bladder or the rectum, the procedure should be stopped and completed at a future date. After the cervix is visualized, the goal is to reapproximate the upper mucosal tissue to the lower vaginal mucosa. Z-plasty Technique
Figure 51-21
Schematic of obstructing longitudinal septum.
Figure 51-22
Partial transverse septum.
through the angiocath, the plane of dissection becomes clear. Access is gained into the upper vaginal cavity by perforating a bulging transverse septum with unipolar electrosurgery or scissors (Fig. 51-21). The septum is excised in its entirety and the upper vaginal mucosa is reapproximated to the lower vaginal mucosa using 2-0 absorbable suture (Fig. 51-22). In most instances, to prevent stenosis of the vagina, continual use of a mold is recommended for several weeks after surgery. Surgical Technique: Thick Transverse Vaginal Septum
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Managing thick transverse septa can be quite challenging. Before surgery, the patient must be prepared for prolonged use of a mold and possible split-thickness skin graft to line the vagina. The main concern is potential bowel injury; therefore, bowel preparation is recommended.
If a thick septum is completely incised, the distance between the vaginal mucosa of the proximal and distal portions of the vagina may be so great that the edges cannot be reapproximated without tension. For this reason, a Z-plasty technique, as first described by Garcia and colleagues, should be considered for correction of thick transverse vaginal septa or when the vagina is short.102 For this technique, four lower mucosal flaps are created by making oblique crossed incisions through the vaginal tissue on the perineal side of the transverse septum, taking great care to avoid injuring either the bladder or rectum.103 Four upper mucosal flaps are created by making oblique crossed incisions through the vaginal tissue on the hematocolpos side of the transverse septum. The upper and lower mucosal flaps are separated by sharp and blunt dissection and sutured together at their free edges to form a continuous Z-plasty. Excellent results have been noted on 13 patients who underwent this procedure.103 A vaginal mold must be used for 5 to 8 weeks after the procedure to avoid vaginal stenosis. If the girl is not sexually active, a dilator should be used at night for 6 to 8 additional months. The patient should be instructed in selfexamination and should return if she notices any signs of early stenosis. In cases of a thick septum where a Z-plasty technique is not used, a skin graft may be required. The technique utilized is similar to that described for the McIndoe procedure. Prolonged use of a mold is required postoperatively.
MANAGEMENT OF MALFORMATIONS OF THE EXTERNAL GENITALIA Anomalies of the external genitalia are uncommon but require extreme skill in both surgical technique and patient interaction. The assignment of gender is a critical responsibility of a physician. Chapter 12 outlines the pathophysiology and patient approach in detail.
Gender Assignment and Timing of Surgery Gender assignment and genital surgery for intersex patients remains controversial. Female genitoplasty performed in infancy can markedly complicate gender reassignment later in life. Gender dysphoria has been reported by some patients assigned a female gender of rearing based solely on anatomic considerations during
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Chapter 51 Surgical Management of the Müllerian Ducts and External Genitalia infancy.104 This gender dysphoria may be due to androgen imprinting of the fetal brain. However, the true incidence of gender dysphoria in intersex patients is unknown. The two common options for managing intersex patients are (1) early genital reconstruction, with corresponding assignment of gender, or (2) early assignment of gender of rearing with deferred genital surgery. The advantage of the first option of genital reconstruction in infancy is the unproven psychological benefit of undergoing genital surgery before the age of genital awareness. There is also a perception that healing is more rapid and complete when surgery is performed in infancy. The advantage of the second option is that it allows the patient to participate in the ultimate decisions regarding surgical intervention. Theoretically, this might minimize problems if the patient ultimately elects the gender opposite that assigned. It also allows patients satisfied with a female gender assignment the option of retaining a large clitoris rather than suffering the potential complications of clitoral reduction surgery. Before assigning a gender to an infant with ambiguous genitalia, a frank discussion regarding these issues should be undertaken with the family. A team approach should include the surgeon, an endocrinologist, and a psychiatrist/psychologist with interest in this area. The parents should be given every opportunity to deliberate on the issues and discuss the surgical, psychological, and social implications of each option with each member of the team. Although ethical concerns continue to intensify about early surgery, most surgeons ultimately abide by the parents’ decision.
A
Clitoromegaly Clitoromegaly in a newborn is an indication for a full intersex evaluation. Causes of clitoromegaly in a phenotypic female newborn include partial androgen insensitivity in XY individuals, mild congenital adrenal hyperplasia in XX individuals (Fig. 51-23), and a variety of other rare abnormalities. Therefore the first step in evaluating these patients is to determine the etiology of the clitoromegaly so that the primary problem may be addressed and appropriately managed.
B Figure 51-23 A, Preoperative image of a 6-month-old girl with congenital adrenal hyperplasia. B, A probe has been placed in the genitourinary sinus.
Surgical Technique: Reduction Clitoroplasty
Reduction clitoroplasty is often considered in patients with either isolated clitoromegaly or ambiguous genitalia. Once the cause of the clitoromegaly has been addressed and a decision has been made to proceed with reduction clitoroplasty, a full anatomic evaluation should be performed. Historically, the enlarged clitoris was managed with clitorectomy. However, concern regarding preservation of sexual function led to abandonment of resection in favor of clitoral recession. Clitoral recession was performed by folding the erectile bodies in an accordion fashion and recessing the glans under the pubic symphysis. However, these patients often suffered painful erections with sexual stimulation. This led to development of the reduction clitoroplasty approach. The goal of reduction clitoroplasty is to preserve sexual function by preserving the neural and vascular supply to the glans while excising most of the erectile tissue to prevent painful erections. The first step in reduction clitoroplasty is to identify the vaginal opening. Next, a circumcision is performed and the phallus completely degloved (Fig. 51-24). The circumcision can
Figure 51-24 A circumcision is performed and the phallus completely degloved. The Foley catheter is in the urethra and bladder.
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Clitoral hood
Figure 51-25 A, Lateral incisions are made in the erectile bodies ventral to the neurovascular bodies (see dashed line). B, The erectile tissue is separated from the dorsal tunica and urethral plate and excised.
Dorsal funix with neurovascular bundle
Preserved urethral plate
Corporal tissue to be excised
B
Labia minora
Figure 51-27 The skin flaps are brought down on either side to recreate the labia minora. Figure 51-26 The glans is recessed onto the pubic symphysis and secured with absorbable sutures. Skin flaps are created from the phallus skin.
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be brought across the urethral plate at the base of the shaft, preserving this tissue, which can be used as an anterior flap in the vaginoplasty if desired. The erectile tissue is then separated from the dorsal tunica vaginalis, on top of which run the neurovascular bundles (Fig. 51-25A). The erectile tissue is amputated at the crura and at the glans and excised, preserving the attachments of the dorsal tunica vaginalis and neurovascular bundles (Fig. 51-25B). The glans is then recessed onto the pubic symphysis and secured with absorbable sutures. Glans reduction may be undertaken by excising a ventral wedge of glans. However, this is rarely necessary and risks denervating the residual glans. A dorsal slit is made in the dorsal hood and the apex of this incision secured to the dorsal midline of the glans edge with
absorbable suture (Fig. 51-26). The skin flaps are then brought down on either side to recreate the labia minora (Fig. 51-27). The final result is shown in Figure 51-28. Simultaneous Vaginoplasty
Most patients with clitoromegaly will also have masculinization of the vaginal canal, which will ultimately require vaginoplasty. Although the timing of vaginoplasty is controversial, from a technical point of view, combining the vaginoplasty with the clitoral reduction will result in the best cosmetic outcome. A simple cutback or perineal flap vaginoplasty is most often employed in intersex patients. However, extremely virilized patients may require a more formal pull-through with or without surgical separation of the vagina and urethra. Regardless of the approach to vaginoplasty, the technique for reduction clitoroplasty remains the same.
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Chapter 51 Surgical Management of the Müllerian Ducts and External Genitalia children with preservation of the neurovascular bundle found that each had markedly abnormal clitoral sensation.107,109 In another study of sexually active women who had undergone nerve-sparing reduction clitoroplasty as infants, 2 of 3 patients had the worst possible score for orgasm difficulties. Clearly, detailed multicenter outcome studies of feminizing genitoplasty are needed. Until such studies are avaiable, parents and patients consenting to this procedure should be aware of the likely need for additional surgery later in life and the likelihood that even modern techniques may result in significant clitoral denervation and dissatisfaction with cosmetic outcomes.
PEARLS
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B Figure 51-28 the urethra.
Final result of reductive surgery. The Foley catheter is in ●
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Outcome Data
The little data available regarding the outcome of clitoral surgery does not support the routine application of this procedure during infancy. However, it must be kept in mind that the majority of patients thus far studied had surgery before the widespread acceptance of reduction clitoroplasty. Several small retrospective studies of patients assigned a female gender undergoing feminizing genitoplasty as infants have found a high incidence of sexual dysfunction, loss of clitoral sensation, anorgasmia, and dissatisfaction with cosmesis.104–108 One small series of women born with ambiguous genitalia found that those who underwent clitoral surgery as infants had significantly more sexual problems than a comparable group who did not.105 Cosmetic outcome is often poor after clitoral surgery performed during infancy and reoperation later is usually required.106 Nerve-sparing procedures do not appear to fare much better. A study of 6 women who had undergone clitoral reduction as
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Patients with müllerian agenesis typically present during their adolescent years with complaint of primary amenorrhea. Müllerian agenesis is associated with renal and skeletal system anomalies. With the advent of MRI, laparoscopy is no longer considered necessary to make the diagnosis of müllerian agenesis. The American College of Obstetricians and Gynecologists recently released a committee opinion that recommends nonsurgical management of müllerian agenesis as the first mode of treatment. The most widely used surgical technique for creation of a neovagina is the McIndoe operation. An 80% success rate has been reported with the McIndoe operation. Patients with cervical agenesis present between ages 12 and 16 with a primary complaint of pelvic pain secondary to obstruction of flow from the uterus. Patients with cervical agenesis who lack a vagina must be differentiated from those with a high obstructing vaginal septum. It is important to differentiate a bicornuate from a septate uterus. HSG alone cannot differentiate these entities. Conception does not appear to be a problem in women with bicornuate uterus. However, higher rates of preterm delivery and spontaneous abortion have been reported. A unicornuate uterus may be associated with a communicating or noncommunicating rudimentary horn. Women with an obstructing longitudinal septum usually present with normal onset menarche and increasingly severe dysmenorrhea. Patients with a complete transverse vaginal septum generally present with a complaint of primary amenorrhea in early to mid puberty. An alternative to early surgery for very young patients with a transverse vaginal septum is medical termination of monthly endometrial shedding using DMPA to postpone surgery. Reduction clitoroplasty is often considered in patients with either isolated clitoromegaly or ambiguous genitalia.
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1. Buttram VC Jr, Gibbons WE: Müllerian anomalies: A proposed classification. Fertil Steril 32:40–46, 1979. 2. Toaff ME, Lev-Toaff AS, Toaff R: Communicating uteri: Review and classification with introduction of two previously unreported types. Fertil Steril 41:661–679, 1984. 3. Acien P, Acien M, Sanchez-Ferrer M: Complex malformations of the female genital tract. New types and revision of classification. Hum Reprod 19:2377–2384, 2004. 4. Jones HW Jr: Reproductive impairment and the malformed uterus. Fertil Steril 36:137–148, 1981. 5. The American Fertility Society classifications of adnexal adhesions, distal tubal occlusion, tubal occlusion secondary to tubal ligation, tubal pregnancies, müllerian anomalies and intrauterine adhesions. Fertil Steril 49:944–955, 1988. 6. Aittomaki K, Eroila H, Kajanoja P: A population-based study of the incidence of müllerian aplasia in Finland. Fertil Steril 76:624–625, 2001. 7. Reindollar RH, Byrd JR, McDonough PG: Delayed sexual development: A study of 252 patients. Am J Obstet Gynecol 140:371–380, 1981. 8. Fraser IS, Baird DT, Hobson BM, et al: Cyclical ovarian function in women with congenital absence of the uterus and vagina. J Clin Endocrinol Metab 36:634–637, 1973. 9. Petrozza JC, Gray MR, Davis AJ, Reindollar RH: Congenital absence of the uterus and vagina is not commonly transmitted as a dominant genetic trait: Outcomes of surrogate pregnancies. Fertil Steril 67:387–389, 1997. 10. Strubbe EH, Cremers CW, Dikkers FG, Willemsen WN: Hearing loss and the Mayer-Rokitansky-Küster-Hauser syndrome. Am J Otol 15:431–436, 1994. 11. Willemsen WN: Renal, skeletal, ear, and facial anomalies in combination with the Mayer-Rokitansky-Küster (MRK) syndrome. Eur J Obstet Gynecol Reprod Biol 14:121–130, 1982. 12. Letterie GS, Vauss N: Müllerian tract abnormalities and associated auditory defects. J Reprod Med 36:765–768, 1991. 13. Buttram VC Jr: Müllerian anomalies and their management. Fertil Steril 40:159–163, 1983. 14. Griffen JE, Creighton E, Madden JD, et al: Congenital absence of the vagina: The Mayer-Rokitansky-Küster-Hauser syndrome. Ann Intern Med 85:224–236, 1976. 15. Frank RT: The formation of an artificial vagina without operation. Am J Obstet Gynecol 35:1053–1057, 1938. 16. Committee on Adolescent Health Care. American College of Obstetricians and Gynecologists: Nonsurgical diagnosis and management of vaginal agenesis. ACOG Committee Opinion no. 274, July 2002. Int J Gynaecol Obstet 79:167–170, 2002. 17. Ingram JM: The bicycle seat stool in the treatment of vaginal agenesis and stenosis: A preliminary report. Am J Obstet Gynecol 140:867–873, 1981. 18. Roberts CP, Haber MJ, Rock JA: Vaginal creation for müllerian agenesis. Am J Obstet Gynecol 185:1349–1352, 2001. 19. Poland ML, Evans TN: Psychologic aspects of vaginal agenesis. J Reprod Med 30:340–344, 1985. 20. Weijenborg PT, ter Kuile MM: The effect of a group programme on women with the Mayer-Rokitansky-Küster-Hauser syndrome. BJOG 107:365–368, 2000. 21. Edmonds DK: Congenital malformations of the genital tract. Obstet Gynecol Clin North Am 27:49–62, 2000. 22. Robson S, Oliver GD: Management of vaginal agenesis: Review of 10 years practice at a tertiary referral centre. Aust NZ J Obstet Gynaecol 40:430–433, 2000. 23. Costa EM, Mendonca BB, Inacio M, et al: Management of ambiguous genitalia in pseudohermaphrodites: New perspectives on vaginal dilation. Fertil Steril;67:229–232, 1997. 24. Vecchietti G: Neovagina nella sindrome di Rokitansky Küster-Hauser. Attual Obstet Gynecol 11:131–147, 1965. 25. Veronikis DK, McClure GB, Nichols DH: The Vecchietti operation for constructing a neovagina: Indications, instrumentation, and techniques. Obstet Gynecol 90:301–304, 1997.
26. Chatwani A, Nyirjesy P, Harmanli OH, Grody MH: Creation of neovagina by laparoscopic vecchietti operation. J Laparoendosc Adv Surg Tech 9:425–427, 1999. 27. Borruto F: Mayer-Rokitansky-Küster syndrome: Vecchietti’s personal series. Clin Exp Obstet Gynecol 19:273–274, 1992. 28. Fedele L, Bianchi S, Zanconato G, Raffaelli R: Laparoscopic creation of a neovagina in patients with Rokitansky syndrome: Analysis of 52 cases. Fertil Steril 74:384–389, 2000. 29. Borruto F, Chasen ST, Chervenak FA, Fedele L: The Vecchietti procedure for surgical treatment of vaginal agenesis: Comparison of laparoscopy and laparotomy. Int J Gynaecol Obstet 64:153–158, 1999. 30. Kaloo P, Cooper M: Laparoscopic-assisted Vecchietti procedure for creation of a neovagina: An analysis of five cases. Aust NZ J Obstet Gynaecol 42:307–310, 2002. 31. Buss JG, Lee RA: McIndoe procedure for vaginal agenesis: Results and complications. Mayo Clin Proc 64:758–761, 1989. 32. Counseller VS, Flor FS: Congenital absence of the vagina. Surg Clin North Am 37:1107, 1957. 33. Alessandrescu D, Peltecu GC, Buhimschi CS, Buhimschi IA: Neocolpopoiesis with split-thickness skin graft as a surgical treatment of vaginal agenesis: Retrospective review of 201 cases. Am J Obstet Gynecol 175:131–138, 1996. 34. Hojsgaard A, Villadsen I: McIndoe procedure for congenital vaginal agenesis: Complications and results. B J Plastic Surg 48:97–102, 1995. 35. Mobus VJ, Kortenhorn K, Kreienberg R, Friedberg V: Long-term results after operative correction of vaginal aplasia. Am J Obstet Gynecol 175:617–624, 1996. 36. Klingele CJ, Gebhart JB, Croak AJ, et al: McIndoe procedure for vaginal agenesis: Long-term outcome and effect on quality of life. Am J Obstet Gynecol 189:1569–1572, 2003. 37. Hopkins MP, Morley GW: Squamous cell carcinoma of the neovagina. Obstet Gynecol 69:525–527, 1987. 38. Baltzer J, Zander J: Primary squamous cell carcinoma of the neovagina. Gynecol Oncol 35:99–103, 1989. 39. Davydov SN: [12-year experience with colpopoiesis using the peritoneum]. Gynakologe 13:120–121, 1980. 40. Davydov SN: [Colpopoeisis from the peritoneum of the uterorectal space]. Akush Ginekol (Mosk) 45:55–57, 1969. 41. Rothman D: The use of peritoneum in the construction of a vagina. Obstet Gynecol 40:835–838, 1972. 42. Soong YK, Chang FH, Lai YM, Lee CL, Chou HH: Results of modified laparoscopically assisted neovaginoplasty in 18 patients with congenital absence of vagina. Hum Reprod 11:200–203, 1996. 43. Templeman CL, Hertweck SP, Levine RL, Reich H: Use of laparoscopically mobilized peritoneum in the creation of a neovagina. Fertil Steril 74:589–592, 2000. 44. Rangaswamy M, Machado NO, Kaur S, Machado L: Laparoscopic vaginoplasty: Using a sliding peritoneal flap for correction of complete vaginal agenesis. Eur J Obstet Gynecol Reprod Biol 98:244–248, 2001. 45. Jackson ND, Rosenblatt PL: Use of Interceed absorbable adhesion barrier for vaginoplasty. Obstet Gynecol 84:1048–1050, 1994. 46. Motoyama S, Laoag-Fernandez JB, Mochizuki S, et al: Vaginoplasty with Interceed absorbable adhesion barrier for complete squamous epithelialization in vaginal agenesis. Am J Obstet Gynecol 188:1260–1264, 2003. 47. Ashworth MF, Morton KE, Dewhurst J, et al: Vaginoplasty using amnion. Obstet Gynecol 67:443–446, 1986. 48. Akle CA, Adinolfi M, Welsh KI, et al: Immunogenicity of human amniotic epithelial cells after transplantation into volunteers. Lancet 2:1003–1005, 1981. 49. Robson MC, Krizek TJ: The effect of human amniotic membranes on the bacteria population of infected rat burns. Ann Surg 177:144–149, 1973. 50. Dhall K: Amnion graft for treatment of congenital absence of the vagina. BJOG 91:279–282, 1984. 51. Tobin GR, Day TG: Vaginal and pelvic reconstruction with distally based rectus abdominis myocutaneous flaps. Plast Reconstr Surg 81:62–73, 1988.
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Chapter 51 Surgical Management of the Müllerian Ducts and External Genitalia 52. McCraw JB, Massey FM, Shanklin KD, Horton CE: Vaginal reconstruction with gracilis myocutaneous flaps. Plast Reconstr Surg 58:176–183, 1976. 53. Wee JT, Joseph VT: A new technique of vaginal reconstruction using neurovascular pudendal-thigh flaps: A preliminary report. Plast Reconstr Surg 83:701–709, 1989. 54. Joseph VT: Pudendal–thigh flap vaginoplasty in the reconstruction of genital anomalies. J Pediatr Surg 32:62–65, 1997. 55. Monstrey S, Blondeel P, Van Landuyt K, et al: The versatility of the pudendal thigh fasciocutaneous flap used as an island flap. Plast Reconstr Surg 107:719–725, 2001. 56. Song R, Wang X, Zhou G: Reconstruction of the vagina with sensory function. Clin Plast Surg 9:105–108, 1982. 57. Belloli G, Campobasso P, Musi L: Labial skin-flap vaginoplasty using tissue expanders. Pediatr Surg Int 12:168–171, 1997. 58. Chudacoff RM, Alexander J, Alvero R, Segars JH: Tissue expansion vaginoplasty for treatment of congenital vaginal agenesis. Obstet Gynecol 87:865–868, 1996. 59. Fliegner JR: A simple surgical cure for congenital absence of the vagina. Aust NZ J Surg 56:505–508, 1986. 60. Fliengrer JR: Congenital atresia of the vagina. Surg Gynecol Obstet 165:387–391, 1987. 61. Parsons JK, Gearhart SL, Gearhart JP: Vaginal reconstruction utilizing sigmoid colon: Complications and long-term results. J Pediatr Surg 37:629–633, 2002. 62. Syed HA, Malone PS, Hitchcock RJ: Diversion colitis in children with colovaginoplasty. BJU Int 87:857–860, 2001. 63. Hiroi H, Yasugi T, Matsumoto K, et al: Mucinous adenocarcinoma arising in a neovagina using the sigmoid colon thirty years after operation: A case report. J Surg Oncol 77:61–64, 2001. 64. Darai E, Soriano D, Thoury A, Bouillot JL: Neovagina construction by combined laparoscopic-perineal sigmoid colpoplasty in a patient with Rokitansky syndrome. J Am Assoc Gynecol Laparosc 9:204–208, 2002. 65. Ota H, Tanaka J, Murakami M, et al: Laparoscopy-assisted ruge procedure for the creation of a neovagina in a patient with MayerRokitansky-Küster-Hauser syndrome. Fertil Steril 73:641–644, 2000. 66. Edmonds DK: Diagnosis, clinical presentation and mangement of cervical agenesis. In Gidwani G, Falcone T (eds). Congenital Malformations of the Female Genital Tract: Diagnosis and Management. Philadelphia, Lippincott Williams & Wilkins 1999, pp 169–176. 67. Rock J, Breech L: Surgery for anomalies of the müllerian ducts. In Rock JA, Jones HW 3rd (eds). Te Linde’s Operative Gynecology, 9th ed. Philadelphia, Lippincott Williams & Wilkins 2003, pp 705–752. 68. Fujimoto VY, Miller JH, Klein NA, Soules MR: Congenital cervical atresia: Report of seven cases and review of the literature. Am J Obstet Gynecol 177:1419–1425, 1997. 69. Letterie GS: Combined congenital absence of the vagina and cervix. Diagnosis with magnetic resonance imaging and surgical management. Gynecol Obstet Invest 46:65–67, 1998. 70. Markham SM, Parmley TH, Murphy AA, et al: Cervical agenesis combined with vaginal agenesis diagnosed by magnetic resonance imaging. Fertil Steril 48:143–145, 1987. 71. Reinhold C, Hricak H, Forstner R, et al: Primary amenorrhea: Evaluation with MR imaging. Radiology 203:383–390, 1997. 72. Bugmann P, Amaudruz M, Hanquinet S, et al: Uterocervicoplasty with a bladder mucosa layer for the treatment of complete cervical agenesis. Fertil Steril 77:831–835, 2002. 73. Deffarges JV, Haddad B, Musset R, Paniel BJ: Utero-vaginal anastomosis in women with uterine cervix atresia: Long-term follow-up and reproductive performance. A study of 18 cases. Hum Reprod 16:1722–1725, 2001. 74. Hovsepian DM, Auyeung A, Ratts VS: A combined surgical and radiologic technique for creating a functional neo-endocervical canal in a case of partial congenital cervical atresia. Fertil Steril 71:158–162, 1999. 75. Rock JA, Carpenter SE, Wheeless CR, Jones HW 3rd: The clinical management of maldevelopment of the uterine cervix. J Pelv Surg 1:129–133, 1995.
76. Casey AC, Laufer MR: Cervical agenesis: Septic death after surgery. Obstet Gynecol 90:706–707, 1997. 77. Jacob JH, Griffin WT: Surgical reconstruction of the congenitally atretic cervix: Two cases. Obstet Gynecol Surv 44:556–569, 1989. 78. Grimbizis GF, Camus M, Tarlatzis BC, et al: Clinical implications of uterine malformations and hysteroscopic treatment results. Hum Reprod Update 7:161–174, 2001. 79. Acien P: Incidence of müllerian defects in fertile and infertile women. Hum Reprod 12:1372–1376, 1997. 80. Pui MH: Imaging diagnosis of congenital uterine malformation. Comput Med Imaging Graph 28:425–433, 2004. 81. Krysiewicz S: Infertility in women: Diagnostic evaluation with hysterosalpingography and other imaging techniques. AJR 159:253–261, 1992. 82. Acien P: Reproductive performance of women with uterine malformations. Hum Reprod 8:122–126, 1993. 83. Patton PE: Anatomic uterine defects. Clin Obstet Gynecol 37:705–721, 1994. 84. Heinonen PK: Clinical implications of the didelphic uterus: Long-term follow-up of 49 cases. Eur J Obstet Gynecol Reprod Biol 91:183–190, 2000. 85. Jayasinghe Y, Rane A, Stalewski H, Grover S: The presentation and early diagnosis of the rudimentary uterine horn. Obstet Gynecol 105:1456–1467, 2005. 86. O’Leary JL, O’Leary JA: Rudimentary horn pregnancies. Obstet Gynecol 22:371, 1963. 87. Falcone T, Hemmings R, Kalife R: Laparoscopic management of a unicornuate uterus with a rudimentary horn. J Gynecol Surg 11:105–107, 1995. 88. Falcone T, Gidwani G, Paraiso M, et al: Anatomic variation in the rudimentary horns of a unicornuate uterus: Implications for laparoscopic surgery. Hum Reprod 12:263–265, 1997. 89. Haddad B, Louis-Sylvestre C, Poitout P, Paniel BJ: Longitudinal vaginal septum: A retrospective study of 202 cases. Eur J Obstet Gynecol Reprod Biol 74:197–199, 1997. 90. Heinonen PK: Longitudinal vaginal septum. Eur J Obstet Gynecol Reprod Biol 13:253–258, 1982. 91. Carey MP, Steinberg LH: Vaginal dystocia in a patient with a double uterus and a longitudinal vaginal septum. Aust NZ J Obstet Gynaecol 29:74–75, 1989. 92. Candiani GB, Fedele L, Candiani M: Double uterus, blind hemivagina, and ipsilateral renal agenesis: 36 cases and long-term follow-up. Obstet Gynecol 90:26–32, 1997. 93. Montevecchi L, Valle RF: Resectoscopic treatment of complete longitudinal vaginal septum. Int J Gynaecol Obstet 84:65–70, 2004. 94. Tsai EM, Chiang PH, Hsu SC, et al: Hysteroscopic resection of vaginal septum in an adolescent virgin with obstructed hemivagina. Hum Reprod 13:1500–1501, 1998. 95. Sanfilippo JS, Wakim NG, Schikler KN, Yussman MA: Endometriosis in association with uterine anomaly. Am J Obstet Gynecol 154:39–43, 1986. 96. Stassart JP, Nagel TC, Prem KA, Phipps WR: Uterus didelphys, obstructed hemivagina, and ipsilateral renal agenesis: The University of Minnesota experience. Fertil Steril 57:756–761, 1992. 97. Rock JA, Zacur HA, Dlugi AM, et al: Pregnancy success following surgical correction of imperforate hymen and complete transverse vaginal septum. Obstet Gynecol 59:448–451, 1982. 98. Lodi A: Contributo clinico stastico sulle malformazioni della vagina osservate mella. Clinica obstetricia e ginecologia di Milano dal 1906 al 1950. Ann Obstet Gynecol Med Perinatol 73:1246, 1951. 99. Rock JA, Zacur HA, Dlugi AM, et al: Pregnancy success following surgical correction of imperforate hymen and complete transverse vaginal septum. Obstet Gynecol 59:448–451, 1982. 100. Joki-Erkkila MM, Heinonen PK: Presenting and long-term clinical implications and fecundity in females with obstructing vaginal malformations. J Pediatr Adolesc Gynecol 16:307–312, 2003. 101. Hurst BS, Rock JA: Preoperative dilatation to facilitate repair of the high transverse vaginal septum. Fertil Steril 57:1351–1353, 1992.
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Section 7 Reproductive Surgery 102. Garcia RF: Z-plasty for correction of congenital transverse vaginal septum. Am J Obstet Gynecol 99:1164–1165, 1967. 103. Wierrani F, Bodner K, Spangler B, Grunberger W: “Z”-plasty of the transverse vaginal septum using Garcia’s procedure and the Grunberger modification. Fertil Steril 79:608–612, 2003. 104. Nelson CP, Gearhart JP: Current views on evaluation, management, and gender assignment of the intersex infant. Nat Clin Pract Urol 1:38–43, 2004. 105. Minto CL, Liao LM, Woodhouse CR, et al: The effect of clitoral surgery on sexual outcome in individuals who have intersex conditions with ambiguous genitalia: A cross-sectional study. Lancet 361:1252–1257, 2003.
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106. Creighton SM, Minto CL, Steele SJ: Objective cosmetic and anatomical outcomes at adolescence of feminising surgery for ambiguous genitalia done in childhood. Lancet 358:124–125, 2001. 107. Crouch NS, Minto CL, Laio LM, et al: Genital sensation after feminizing genitoplasty for congenital adrenal hyperplasia: A pilot study. BJU Int 93:135–138, 2004. 108. Creighton S: Surgery for intersex. J R Soc Med 94:218–220, 2001. 109. Gearhart JP, Burnett A, Owen JH: Measurement of pudendal evoked potentials during feminizing genitoplasty: Technique and applications. J Urol 153:486–487, 1995.
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52
Adhesion Prevention Mohamed F. Mitwally and Michael P. Diamond
INTRODUCTION The relevance of pelvic and peritoneal adhesions to the practice of reproductive endocrinology and infertility clearly relates to their association with infertility and chronic pelvic pain. In addition, postoperative adhesions are also responsible for significant complications, most notably adhesive bowel obstruction, and increase the difficulty of subsequent surgical procedures, which enhances the potential for intraoperative complications. Interestingly, the first case report of fatal intestinal obstruction caused by intra-abdominal adhesions was a woman who developed adhesions after removal of an ovarian tumor.1 Although the peritoneal cavity is of interest to the reproductive surgeon, postoperative adhesions also occur in other spaces, such as the pleural and pericardial cavities. This chapter first describes the scope and impact of pelvic adhesions, as well as the patholophysiology of their formation. This is followed by a careful examination of the complications and clinical conditions associated with adhesions. The final section is a thorough look at what is known about prevention.
HISTORICAL PERSPECTIVE Ancient Egyptians, known for their detailed descriptions of human anatomy, described pelvic adhesions several thousands years ago. Pleural adhesions were first described in the Babylonian Talmud in 440 A.D.2 Although adhesions caused by peritonitis have been recognized since the early 1700s, it was not until the widespread use of anesthesia in the mid-1800s when invasive abdominal procedures became more prevalent that the extent of the problems caused by intra-abdominal adhesions was realized. By the 1880s, the first published reports describing the use of adjuvants for adhesion prevention began to appear in the surgical literature. Over the next 100 years, a plethora of scientific reports and anecdotal accounts described the use of everything from amniotic fluid, bovine cecum, gold-beater’s skin, shark peritoneum, fish bladder, vitreous of calf ’s eyes, various gums, lubricants, fluids, gels, polymers, physical barriers, and a host of mechanical separation methods to prevent adhesions. Unfortunately, the results of most of these studies were equivocal, with no more than a small percentage of success. Even in this age of surgical sophistication and new operating room technology, our age-old nemesis, the intra-abdominal adhesion, remains a significant, long-term, and recurrent postoperative problem.3
DEFINITION, TYPE, AND EXTENT OF DISEASE Intra-abdominal adhesions are strands or membranes of fibrous tissue that can be attached to the various intra-abdominal organs, sometimes connecting them together (Fig. 52-1). The term adhesion in the medical field refers to the abnormal joining of anatomic structures at sites where no such anatomic attachment should exist. Adhesions usually develop in conjunction with surgery at sites of adhesiolysis and other operative sites, but also occur at “distant” sites where no surgical procedure was done. There are two general categories of adhesions, de novo and reformation. De novo adhesions occur at sites that did not previously have adhesions; reformation refers to adhesion formation at sites of previous adhesiolysis. To accurately describe the extent of peritoneal adhesions during clinical investigations, various scoring systems have been developed. Systematic assessment of adhesions is mandatory to decrease interobserver variation and to provide quantitative data corresponding to their extent and clinical significance.4 Most of the available scoring systems incorporate adhesion location, vascularity, and type (thickness). However, the current scoring systems suffer from the lack of validation for outcomes such as fertility, pain, and bowel obstruction, which makes the interpretation of the results of research related to adhesion development and prevention difficult. Thus, the question is often asked that if a study demonstrates a significant change in an adhesion score, does that reflect true clinical relevance in the extent of adhesive disease?
PREVALENCE OF DISEASE Despite the application of microsurgical technique and use of surgical adjuvants by experienced surgeons, the development of intraperitoneal postoperative adhesions is common. Currently, no serum marker or scanning technique is consistently able to identify adhesions, and a repeat operative procedure is required for evaluation.5 In a postmortem study of victims of motor vehicle accidents, intra-abdominal adhesions were encountered in 67% of individuals who had a history of abdominal operation.6 The prevalence among patients who had undergone major operations and multiple procedures was 81% and 93%, respectively. Most studies have shown that after an intra-abdominal operation, most patients
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Figure 52-1 Pelvic adhesions involving the uterus and bowel. This patient had a previous myomectomy.
developed adhesions. One study found that after merely one previous abdominal operation, 93% of patients had adhesions.7 On the other hand, intra-abdominal adhesions among patients who had never experienced a laparotomy were found in only 10.4%. Within 1 year of laparotomy, 1% of patients develop adhesionrelated intestinal obstruction;7 11% to 12% of them will suffer from recurrence later.8 In reports based on data from laparoscopies9 and autopsies,6 60% and 69% of women, respectively, had pelvic adhesions after previous abdominopelvic operations. Variation in the incidence of postoperative adhesions may be explained by differences in the extent of surgery, differences in the incidence or severity of prior surgery or other etiologic events, and in what each investigator considered to be a “significant” adhesion. It is important to emphasize that although some investigators believe all adhesions may not be clinically significant, others would emphasize that you cannot tell which adhesions will cause pain or contribute to bowel obstruction.
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The economic impact of adhesions as a complication of surgery is enormous. In the United States, 446,000 procedures were performed annually to remove abdominopelvic adhesions.10 This included 347,000 operations to release peritoneal adhesions and approximately 100,000 procedures to liberate intestinal adhesions. The cost of morbidity associated with adhesions is large.11 Few studies have been conducted to evaluate the financial impact of adhesion-related problems on the medical budget, and many of the studies could have underestimated the actual financial impact of adhesive disease by not considering the costs of performing diagnostic tests, consultations with other services such as gastroenterology, the increase in operative time required to free adhesions, and the complications due to inadvertent injury to other vital structures while freeing adhesions. In addition, a significant number of planned laparoscopic surgeries are converted to laparotomy because of failure to safely enter the
abdomen and achieve adequate pneumoperitoneum. Finally, there are costs associated with long-term morbidity such as adhesionrelated infertility and repeated admissions for bowel obstruction. The psychological impact of adhesion-related conditions that lead to loss of work might add to the economic burden. In the United States, an analysis of all hospitalizations for adhesions was performed using the 1988 National Hospital Discharge Survey. Of a total 281,982 hospitalizations, 51,100 were adhesion-related admissions. In total, there were more than 948,000 hospital-days of care, accounting for a cost of approximately $1.18 billion.10 In 1994, the same authors updated their database and found the annual overall cost to be approximately $1.3 billion. They also reported that lysis of adhesions was responsible for 1% of hospitalization in the United States.12 In a study that evaluated hospital discharge for adhesionrelated bowel obstruction between 1990 and 1996, the total number of patients increased from 115,067 in 1990 with a total length of hospitalization of 962,642 days to 139,716 patients with a total length of hospitalization of 885,396 days in 1996.13 The total costs increased steadily from $924 million in 1990 to $1.4 billion in 1996. Among those who were treated medically, there were 88,601 hospitalizations in 1990 and 110,817 in 1996, with a parallel increase of cost from $261 million in 1990 to $386 million in 1996. In the United Kingdom, Menzies and coworkers14 reviewed 110 hospital admissions resulting from adhesion-related smallbowel obstruction over a 2-year period. Of 110 admissions, surgical treatment was performed in 37% of patients and conservative management in the remaining patients. The total costs per admission were $7,521.28 (£4,677.41) and $2582.69 (£1,606.15) for the surgical and conservative treatment groups, respectively. In Sweden, Holmdhal and Riseberg15 conducted a cost analysis study on adhesion-related admission among all general surgeons. Collection of data was performed after the authors analyzed the questionnaire sent to all department heads of Swedish surgical units. There were a total of 6200 patients requiring hospitalizations, accounting for 3.5% of all laparotomies. They found that the total cost for adhesion-related hospitalization was $6.1 million US annually or close to $1 million US per million Swedish inhabitants (the population of Sweden is 8.5 million). Because of the difference in medical costs in various countries, meaningful comparisons are difficult. However, all studies suggest a huge financial impact of adhesion-related conditions to the healthcare system. Recently, Wilson16 calculated that a low-cost product with a 25% efficacy in preventing surgical adhesions could potentially generate a cost saving of £55 million over a 10-year period in the UK. In a prior study, they concluded that demonstrating the clinical effectiveness of adhesion reduction products in a randomized, controlled setting is unlikely to be feasible due to the large number of patients required. They suggested that products costing £200 (around $300 US) or more are unlikely to pay back their direct costs.17
COMPLICATIONS OF ADHESIONS Postoperative adhesions develop after virtually every transperitoneal operation, ranging from minimal scarring present on serosal surface to dense agglutination of nearly all structures. However, postoperative adhesions are much more common than
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Chapter 52 Adhesion Prevention symptoms would suggest; therefore, most adhesions probably do not lead to acute symptoms or clinical sequelae. In certain situations, adhesions may be of benefit. They may serve as adjuncts to the body’s natural defenses against intraabdominal insults and can be lifesaving in the postoperative period by localizing leakage from suture lines, isolating an inflammatory collection, or preventing the spread of infection. Other potential benefits include neovascularization of ischemic structures such as anastomoses. However, adhesions are associated with significant morbidity such as infertility, pain, and bowel obstruction.18
Reproductive Problems Adhesions play a significant role in the etiology of several reproductive disorders, including infertility, ectopic pregnancy, and recurrent pregnancy loss (intrauterine adhesions). From 15% to 20% of female infertility is caused by adhesions.19 Adhesions causing infertility or ectopic pregnancy may originate from endometriosis, infection such as pelvic inflammatory disease, appendicitis, or tuberculosis, as well as inflammatory bowel disease and surgery. More details on adhesions and infertility, ectopic pregnancy, and recurrent pregnancy loss are provided in other chapters of this text (see Chapters 34, 41, 47 and 48).
Intestinal Obstruction Adhesive intestinal obstruction is the most serious complication associated with peritoneal adhesions (Fig. 52-2). In addition to the significant pain, the condition can be life-threatening and in some cases fatal. In the early 20th century, most of the cases of intestinal obstruction were due to strangulated external hernias. As abdominal and gynecologic surgeries began to be performed more routinely, the number of intestinal obstructions caused by postsurgical adhesions increased and now has surpassed those produced secondary to hernias. This statistic, however, only holds true for the western world. In poorer regions of the world, the percentage of obstruction from hernias is still greater than that caused by adhesions.20 In advanced countries, adhesions account for intestinal obstructions in 49% to 74% of cases.21 Intestinal surgeries involving the left side of the colon and rectum, appendectomies, and gynecologic procedures are the three most common surgical procedures accounting for adhesionrelated intestinal obstruction.7 Both the extent and indication (e.g., cancer) of a gynecologic operation correlate significantly with the risk of postoperative intestinal obstruction. A Japanese group looked at the type of adhesions that caused intestinal obstruction and found that in 29% of cases, obstructive adhesions were small bowel to small bowel; in 48% the adhesions were small bowel to other abdominopelvic structures.22 Gynecologic malignancy increases the incidence of intestinal obstruction because more extensive operations are often required, and blockage by a tumor mass can occur. A report on 283 gynecologic patients treated for mechanical small-bowel obstruction showed that 175 (61.8%) were due to a primary or recurrent gynecologic malignancy, almost exclusively arising from the ovary.23 However, the second most common cause of obstruction was postoperative adhesions (41 patients, 14.5%), most of which followed an operation performed for a gynecologic cancer.23 Intestinal obstruction occurring in the immediate
Figure 52-2 Radiograph of intestinal obstruction-related bowel adhesions. This patient presented within 1 week of surgery with nausea and vomiting. Plain film of the abdomen in the supine and upright positions was obtained. The classic signs of a mechanical bowel obstruction are seen: large loops of bowel in ladder pattern with no gas in the colon. The gas–fluid levels are the classic sign of a small bowel obstruction.
postoperative period and those that follow treatment for earlystage ovarian cancer usually are related to adhesions, whereas delayed obstruction, especially that which occurs in the presence of advanced disease, is usually tumor-related, particularly if radiotherapy is administered.24 Although small-bowel obstruction on a gynecology service occurs most frequently in women with ovarian cancer, it can occur after other extensive pelvic operations, particularly ones associated with significant pelvic infection, such as surgery for tubo-ovarian abscess. It has been suggested that the two structures most commonly involved in adhesions associated with gynecologic surgery are the omentum and the distal small intestine.18 Short, obese women have a particular tendency to develop omental and small-bowel postoperative adhesions, perhaps in part related to longer, more difficult operative procedures.6 Because colonic adhesions are less common and the restricted mesentery can preclude twisting and kinking of the lumen, the colon is involved in adhesive obstruction only 2% to 10% as frequently as the small bowel.6 Among gynecology patients colonic obstruction usually is related to recurrent or persistent pelvic tumor causing extrinsic compression of the rectosigmoid colon.23,24 Adhesive intestinal obstruction after previous surgery can be early or late. According to the general surgery literature, 17% to 29% of intestinal obstruction cases occur within 1 month,25,26
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Section 7 Reproductive Surgery whereas the rest of the cases develop later, from 1 month to several decades after the surgery. After definitive operative management of an intestinal obstruction, the incidence of recurrence is approximately 14%. The factors contributing to occurrence or recurrence of intestinal obstruction are poorly understood.26,27 Fevang and colleagues studied a series of patients that included 500 patients who had a median follow-up of 10 years and a maximum follow-up time of 40 years after adhesive smallbowel obstruction.28 The cumulative recurrence rate for patients operated once for adhesive intestinal obstruction was 18% after 10 years and 29% at 30 years. For patients admitted several times for adhesive intestinal obstruction, the relative risk of recurrent adhesive intestinal obstruction increased with increasing number of prior episodes. The cumulative recurrence rate reached 81% for patients with four or more admissions. Other factors influencing the recurrence rate were the method of treatment of the last previous adhesive intestinal obstruction episode (conservative versus surgical) and the number of abdominal operations before the initial adhesive intestinal obstruction operation. Most recurrent adhesive small-bowel obstruction episodes occurred within 5 years after the previous one, but a considerable risk is still present 10 to 20 years after an adhesive small-bowel obstruction episode.28
The Conundrum of Chronic Pain Syndromes and Adhesions The issue of adhesion-related pain, including chronic pelvic and abdominal pain, dysmenorrhea, and dyspareunia, has been the subject for intense debate.29 There are three important questions that need to be addressed: Do adhesions cause pain? If yes, does the extent of adhesions correlate with the nature and severity of pain? Does adhesiolysis relieve adhesion-related pain? Adhesions May or May Not Cause Pain
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The question as to whether or not adhesions cause pain does not have an entirely satisfactory answer. In favor of this relationship are the findings that adhesions contain nerve fibers30 and are innervated with substance P-containing sensory neurons, suggesting that adhesions themselves are capable of generating pain stimuli and perhaps finally suggesting a mechanism to explain the pain associated with adhesions.31 However, some have criticized reports such as this because of the potential for “tenting” of normal peritoneum during adhesion excision, such that the nerves may have been in normal peritoneum. Additionally, the apparent absence of pain in some patients with massive adhesions in contrast to claims of intense pain by patients with only minimal adhesive disease has led many clinicians to doubt that adhesions alone are “enough” pathology to “cause” pain. Contributing to the confusion is the subjective nature of pain, the intrinsic difficulty in establishing reliable measures of clinical pain, and the lack of behavioral and psychological assessment in reports of pelvic pain in the gynecologic literature. Add to this the lack of noninvasive techniques for accurately observing or quantifying postoperative adhesion development. The magnitude of the problem is great. As many as 20% of patients with acute pelvic inflammatory disease will have chronic pain, much of which is felt to be associated with adhesions.32 It is possible that adhesions that restrict the free movement of pelvic organs would be implicated as a cause of chronic pelvic
pain.33 Approximately 20% to 50% of patients with chronic pain have pelvic adhesions.33,34 Adhesion Extent Does Not Correlate with Nature and Severity of Pain
Although several studies have suggested a significant association between adhesions and chronic pelvic pain, and the location of pain to reflect the site of adhesions, most of these studies failed to show a significant correlation between the extent of adhesions and the severity of pain.20 Similar observations have been made for the relationship between endometriosis and pain. Adhesiolysis Does Not Always Relieve Adhesion-Related Pain
Lysis of adhesions has been proposed as the therapeutic modality of choice for patients suffering from pelvic pain in association with adhesions, and some investigators report the resolution of chronic pain in individuals after lysis of adhesions, whereas others have not noted this effect consistently or have noticed only a very short period of benefit.35,36 Obviously, the “gold standard” study to determine the utility of adhesiolysis for pain relief would be a double-blinded, randomized trial with a control arm, which would control for adhesion reformation and de novo adhesion formation, and follow-up occurring past the point of the expected placebo effect of adhesiolysis surgery. Not surprisingly, such a study would be difficult to execute because of the need to recruit a large number of patients, to perform a second-look procedure to ascertain whether adhesion reformation occurred in those patients having pain relapse after adhesiolysis, and to debate the method to use to quantify patient pain.20 Probably the closest to this ideal study are reports by Swank and colleagues,37,38 who conducted both laparotomy and laparoscopy. Neither of these studies was able to demonstrate a significant benefit of adhesiolysis to the patient population as a whole, although trends were identified. Although each of these studies was randomized, the length of follow-up was limited, and neither included second-look laparoscopy so as to allow correction for new or persisting adhesions.
Other Problems Complicating Adhesions There are several other clinical implications of adhesions, including interference with intraperitoneal therapeutics and difficult repeat surgery. In an effort to improve both the response rates and the overall survival of patients with ovarian carcinoma, investigators have explored the safety and efficacy of antineoplastic agents delivered intraperitoneally for this malignancy. A major impediment to this innovative therapy is inadequate intraperitoneal distribution of drugs whenever extensive adhesions are present.39 Other adhesion-related complications of gynecologic surgery that do not affect fertility have not been well-studied. Voiding dysfunction, ureteral obstruction, and nonspecific gastrointestinal complaints may also be related to postoperative adhesion development.
PATHOPHYSIOLOGY OF ADHESION FORMATION Peritoneal Cavity Repair The abdominal cavity is lined by the peritoneum, which consists of a single layer of mesothelial cells, supported by a basement
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Chapter 52 Adhesion Prevention Table 52-1 The Temporal Relationship of Different Cell Types and Products in the Peritoneal Cavity (Days) after Surgical Injury First Appearance
Peak Levels
Disappearance
Polymorphonuclear cells
Day 1
Day 2
Day 4
Fibrin
Day 1
Day 2
After day 7
Mesothelial cells*
Day 1.5
Day 5–7
Macrophages
Day 1.5
Day 5
Blood vessels
Day 5.5
Day 6
After day 7
*Mesothelial cells covering the wound site; peak levels refers to re-epithelialization.
membrane and an underlying sheet of connective tissue. When it covers the abdominal wall it is called the parietal peritoneum and when it covers viscera it is called the visceral peritoneum. Peritoneal trauma results in mesothelial damage and is accompanied by inflammation. Mesothelial cells balloon and detach from the basal membrane, thereby creating denuded areas.40 Peritoneal injury due to surgery, irradiation, infection, or irritation initiates an inflammatory reaction that increases peritoneal fluid, including proteins and cells. This fibrinous exudate leads to formation of fibrin41 by activation of the coagulation cascade.42 Within this fibrinous exudate, polymorphonuclear cells, macrophages, fibroblasts, and mesothelial cells migrate, proliferate, or differentiate (Table 52-1). Macrophages increase in number and change functions from mainly phagocytosis into secretion of a variety of substances that cause differentiation of progenitor cells into mesothelial cells on the injured surface. Mesothelial cells form islands throughout the injured area, proliferate, and cover the denuded area in short periods of time, usually estimated to be within 5 to 7 days of injury.43 It is important to realize that this process occurs, not just at the edge of the denuded peritoneum, but throughout the surface of the injured area. All these cells, as well as fibroblasts that migrate from underlying tissues, release a variety of substances such as plasminogen system components, arachidonic acid metabolites, reactive oxygen species, cytokines, and growth factors such as interleukins, tumor necrosis factor-α, and transforming growth factors α and β. These factors modulate the process of peritoneal healing and adhesion development at different stages.44
Abnormal Repair The fibrinous exudate and fibrin deposition is an essential part of normal tissue repair, but its complete resolution is required for normal healing without adhesions. The degradation of fibrin is regulated by the plasminogen system. The inactive pro-enzyme plasminogen is converted into plasmin by tissue-type plasminogen activator or urokinase-type plasminogen activator in peritoneum (primarily tissue plasminogen activator [tPA]), which are inhibited by the plasminogen activator inhibitors 1 and 2. Plasmin degrades fibrin into fibrin degradation products. Plasmin can be directly inhibited by plasmin inhibitors (i.e., α2-macroglobulin,α2-antiplasmin, and α1-antitrypsin), but their role in peritoneal fibrinolysis is not well defined. Inhibition of plasminogen activator results in decreased fibrinolysis and allows formation of fibrin gel matrix, the scaffolding for the formation of an adhesion. This usually occurs over 5 to 8 days.
Fibroblasts will invade the fibrin matrix with extracellular matrix deposition, leading to peritoneal adhesions. In addition to fibroblast invasion and extracellular matrix deposition, the formation of new blood vessels has been universally claimed to be important in adhesion development as a means of resupplying oxygen and nutrients and removing metabolic waste.44 During peritoneal healing, cell–cell interactions between mesothelial cells, macrophages, and fibroblasts contribute to the healing of the peritoneum. Adhesion fibroblasts have developed a specific phenotype. Compared with normal peritoneal fibroblasts, adhesion fibroblasts have increased basal levels of collagen I, fibronectin, and other adhesion substances and decreased levels of tPA.45 Readers with greater interest in this area of investigation are referred to a more detailed review.46 To conclude, the balance between fibrin deposition and degradation in the initial days after surgery is critical in determining normal peritoneal healing or adhesion development. If fibrin is completely degraded, remesothelialization leading to normal peritoneal healing without adhesions will occur. In contrast, if fibrin is not completely degraded, it will serve as a scaffold for fibroblast ingrowth with subsequent extracellular matrix deposition and angiogenesis. After abdominal surgery and infection, however, the equilibrium between coagulation and fibrinolysis is disturbed in favor of the coagulation system.47–50
Risk Factors for Developing Adhesions As mentioned earlier, peritoneal repair and adhesion development is the net result of a balance between fibrin deposition as an outcome of the inflammatory process associated with peritoneal injury and fibrinolysis. Fibrinolysis plays a central role in the resolution of the inflammatory exudate, thereby minimizing the risk of adhesion development. This process has primarily been thought to be initiated by mesothelial cells in the region of tissue injury because fibrinolytic activity has been documented within normal mesothelium.51 However, tPA occurs in fibroblasts from human peritoneum and adhesions as well.52,53 Adequate blood supply is critical for normal fibrinolysis to occur. Peritoneal injury associated with ischemia interferes with fibrinolysis and leads to organization rather than resolution of the fibrin–cellular matrix.43 In the absence of ischemia, even large denuded areas of peritoneum usually will heal normally without developing adhesions.54,55 Agents that compromise blood flow within the area of tissue injury increase adhesion development. Thermal injury,56 infection,57 foreign body reaction (i.e., suture),57,58 radiationinduced endarteritis,59 and any other impediment to fibrin degradation increase intraperitoneal adhesions. The effect of electrocautery devoid of significant thermal injury or incomplete hemostasis on fibrinolysis and ultimately on adhesion development has not been adequately studied. Thus, the necessity to control small bleeding vessels and the optimal method to do such (cautery or suture) has yet to be defined. Only conflicting reports concerning these issues exist in the infertility literature.56,60 Fibrinolysis in the abdominal cavity is even more depressed in the presence of infection.61 Intraoperative tissue damage, infections, tissue ischemia, and intra-abdominal presence of foreign material, blood, or bile62,63 all have been shown to be potent causes of peritoneal adhesions. Foreign materials, such as glove powder,64 fluff from surgical
783
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Section 7 Reproductive Surgery packs (gauze lint),65 sutures,58,66 and material extruded from the digestive tract, cause a peritoneal inflammatory reaction, hence increasing the chance of adhesions.67
PREVENTION OF ADHESION DEVELOPMENT Although gynecologic surgery has been a major source of intraperitoneal adhesions and associated morbidity over the past century, most related complications, including adhesions, have been traditionally managed by general surgeons and related surgical subspecialties.68 However, with the establishment of the gynecologic subspecialties of reproductive endocrinology and infertility and gynecologic oncology, gynecologic surgeons developed a directed interest in adhesion development, prevention, and management. This interest is stimulated particularly for reproductive endocrinologists by the relationship between adhesions and impaired fertility4 and for gynecologic oncologists by the increased aptitude to perform all aspects of intestinal surgery,69 as well as the ability to deal with adhesion-related intestinal complications. As residency training programs in obstetrics and gynecology universally provide exposure to both of these subspecialties, all obstetricians and gynecologists should be familiar with the principles of adhesion development and their management.70 The focus of this review is on the pathophysiology of surgically induced adhesions and their prevention. The discussion on pathophysiology and the various approaches to decrease the chance of adhesions may not apply to adhesions that result from specific disease processes such as endometriosis, pelvic inflammatory disease, inflammatory bowel disease, and other adhesiogenic diseases.
Surgical Techniques Prevention of adhesion development starts by adopting adequate surgical techniques involving the application of microsurgical principles that enhance postoperative healing and minimize tissue insults that exacerbate inflammatory reactions. Such principles of microsurgical techniques, including gentle tissue handling, meticulous hemostasis, copious irrigation, prophylaxis against infection, limiting foreign body reaction, and preventing thermal injury, have all been described as means of decreasing adhesion development. These surgical principles apply to all types of operations because they can influence the risks of most complications associated with surgical procedures, not just adhesion development. Of course, application of these principles must be done in the context of the surgical procedure that needs to be conducted and appreciation of other surgical principles such as the need for adequate exposure and use of traction and countertraction. Surgery for, or associated with, peritonitis requires meticulous and thorough elimination of the source of contamination, treatment of infection, and debridement of the abdominal cavity; these are the cornerstones of such types of surgery for the prevention of surgical adhesions as well as intraperitoneal abscess formation. Hemostasis and Tissue Handling
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Achieving meticulous hemostasis and minimizing tissue handling without doubt constitute the two most important surgical
principles in minimizing adhesions. Although the presence of blood at the operative site increases postoperative adhesion development, it is important that hemostasis be achieved in a manner that devitalizes as little surrounding tissue as possible. When possible, the size of pedicles should be minimized and use of electrosurgery should be restricted to the actual bleeding site. With regard to tissue handling, manipulation of structures is required to achieve exposure and perform the procedure. However, tissue damage can often be minimized by the use of atraumatic graspers, moist (not dry) pads and, when feasible, grasping of tissue structures to be excised.4 Value of Precise Tissue Approximation
The value of tissue approximation, including peritoneal closure, is still a subject of intense debate without clearcut recommendations to be generalized. Traditionally, closure of the peritoneum was thought to possibly allow for (1) restoration of anatomy and approximation of tissues for healing; (2) reestablishment of the peritoneal barrier to reduce the risk of infection; (3) reduction of the risk of wound herniation or dehiscence; and (4) minimization of adhesion development.71 The Cochrane database examined the issue of peritoneal closure versus nonclosure in cesarean section. They concluded that there was “no significant difference in short-term morbidity from nonclosure of the peritoneum in cesarean section.”72 It is, however, important to appreciate that the conclusions drawn from cesarean section may not be applicable to general gynecologic surgery due to the obvious differences in the nature of the two surgery types. Although suturing the peritoneum appears to have a more anatomic result than leaving it to heal by secondary intention, the presence of ischemic tissue by sutures causes a predisposition to adhesion development.55 In animal models,73,74 laparotomy closure without peritoneal suturing healed with a lower incidence of adhesions to the wound compared with animals with peritoneal suturing. Postoperative adhesions at the site of closure of the pelvic peritoneum were responsible for bowel obstruction in 85% of cases, with adhesions to the anterior abdominal wall occurring in another 15%.75 Tulandi76 suggested that the currently available evidence suggests that peritoneal suturing is not only unnecessary, but could also be associated with a greater risk of small-bowel obstruction. Another important issue involving whether to precisely approximate tissues together or not is the ovarian cortex closure, such as in surgeries involving the removal of ovarian cysts and masses. In animal studies, suture closure of the ovarian cortex was associated with greater, not lesser, adhesion development.77 Use of Laparoscopy
It had been suggested, anecdotally, that procedures performed by laparoscopy, as opposed to laparotomy, might be less likely to be followed by the postoperative development of pelvic adhesions. Potential explanations included reductions in tissue drying, tissue manipulation, introduction of foreign materials, and abrasion of peritoneal sutures, as well as lack of packing of bowel.78,79 However, in a multicenter study evaluating adhesion reformation at a second-look procedure after laparoscopic adhesiolysis, adhesion reformation was identified in 66 of 68 subjects (97%).80 Laparoscopic adhesiolysis was able to significantly reduce the extent of pelvic adhesions to approximately half of what was present initially. De novo adhesion develop-
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Chapter 52 Adhesion Prevention ment occurred in only 8 (12%) of these 68 women, and in 11 (23%) of 47 available sites in those affected. This suggests that de novo adhesion development (not adhesion reformation) may occur less frequently after laparoscopic surgery, but confirmation of this hypothesis will require properly controlled studies. A recent study made the observation that the increased use of laparoscopy for abdominal procedures between 1988 and 1994 did not appear to be associated with a concomitant reduction in the hospitalization rate for adhesive intestinal obstruction, suggesting that although minimally invasive techniques may offer advantages such as decreased morbidity, whether such procedures actually reduce adhesion development remains unclear at this time.12 Laparoscopic adhesiolysis for adhesive intestinal obstruction has also come to the forefront81 and obviously offers similar advantages over laparotomy. However, there are no long-term results; thus, the question concerning decreased recurrence after laparoscopy compared with laparotomy requires further investigation.
Figure 52-3 sidewall.
Sharp dissection of dense adhesion of tube to the pelvic
CO2 Pneumoperitoneum-Enhanced Adhesion Development
Recently, the effects of carbon dioxide (CO2) pneumoperitoneum have become increasingly scrutinized.82–90 It has been hypothesized that CO2 pneumoperitoneum induces adverse effects, including hypercarbia, acidosis,88 hypothermia, and desiccation,89 as well as altered peritoneal fluid90 and morphology of the mesothelial cells.91 Adhesions have been found to increase with the duration of the pneumoperitoneum and with increased insufflation pressure in rabbits82 and mice.83 Potentially, such adhesions may be due to drying or cooling of tissues from insufflation gas flow; however, this remains controversial. Cooling has been suggested both to cause89 and reduce adhesions,84 while humidification of insufflation gas has been implicated in adhesion reduction85 or having no effect. The pneumoperitoneum-enhanced adhesion development has been suggested to be mediated by mesothelial hypoxia because similar effects were observed with helium pneumoperitoneum, and because the addition of 2% to 4% oxygen to both CO2 and helium pneumoperitoneum decreased adhesion development.83,86 Use of Energy Source
In general, there has been no evidence that use of a specific energy source per se (e.g., CO2 laser, bipolar electrocautery, unipolar electrocautery, harmonic scalpel) results in a greater reduction of adhesions or improvement in pregnancy outcome, compared with other surgical modalities.92–94 However, individual surgeons, based on their own experience, equipment availability, and preference, may find use of a particular modality to be most advantageous for the performance of these procedures.95–98 Technique for Treatment of Existing Adhesions to Prevent Adhesion Reformation
There is no single best method of dividing adhesions, in spite of dogma to the contrary. In some situations, particularly when the adhesions are flimsy and are easily separable, gentle blunt dissection may be the safest method. In other situations, when adhesions are dense and especially when important adjacent structures such as the urinary bladder are involved, blunt dissection or pulling on the small intestine results in tears of the bowel or adherent viscus. This happens primarily because the
tensile strength of the adhesions exceeds that required to maintain bowel or other visceral seromuscular layer intact. Consequently, when adhesions are dense, it is generally safer to use a sharp method of dissection (Fig. 52-3). Similarly, the role of adhesion incision versus excision has not been well studied. Although excision of adhesion bands may in many cases be intuitive so that the resulting raw surfaces will no longer be in apposition, it is perhaps better to leave raw surface area as small as possible, and therefore avoid denudation of visceral surfaces. In all situations, immediate recognition of enterotomy is important because if the operation is terminated without closing the defect, peritonitis will occur in the immediate postoperative period.99
Adhesion Development versus Adhesion Reformation Three groups have demonstrated fundamental differences between adhesion development and adhesion reformation in animal models. Holtz and associates100,101 described reduction in adhesion development with 32% dextran 70, but a similar inhibition of adhesion reformation could not be achieved with higher doses of dextran. Similarly, Elkins and coworkers102,103 observed a greater extent of adhesion reformation than adhesion formation after dextran treatment. Finally, Diamond and associates104,105 compared adhesion formation and reformation models and noted a greater extent of adhesions in the latter. Consistent with these observations, Diamond and Nezhat have proposed a classification of postsurgical adhesion development that differentiates de novo adhesion formation (type I) from adhesion reformation (type II) and subcategorizes each of these groups as to whether there was a lack of or presence of treatment of pathology106 at sites during the initial procedure. Importantly, a recent meta-analysis has validated this classification system by demonstrating increasing risk of adhesions in association with advanced stages.107 Such a system provides a method to assess efficacy of surgical techniques, new instrumentation, and antiadhesion adjuvant therapy.
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Section 7 Reproductive Surgery Second-Look Laparoscopy The value of second-look laparoscopy to promote fertility remains controversial. Multiple series have demonstrated that adhesiolysis in patients with preexisting adhesions results in pregnancy outcomes in inverse correlation with the extent/severity of the initial adhesions (i.e., the more adhesions initially, the less likely pregnancy will occur). Additionally, in other series, adhesiolysis has been shown to reduce the amount of adhesions, which will be identified in the future. The logical deduction from these statements is that secondlook laparoscopies will increase the pregnancy rate. However, well-designed studies examining the effect of early second-look laparoscopies on subsequent pregnancy outcome have not been performed. Advocates of second-look procedures propose several advantages: the ability to assess the efficacy of new surgical techniques, equipment, or adjuvants; the opportunity for the surgeon to assess the outcome of the surgical procedure; and a better opportunity for the patient to be counseled regarding next steps (e.g., recommending in vitro fertilization for patients with extensive adhesions). Nonetheless, these outcomes do not prove clinical benefits regarding pregnancy. Although Tulandi and colleagues were unable to identify a benefit of second-look laparoscopy 1 year after reproductive surgery, this study was limited by the lack of randomization and the differences in the initial surgeons.108 In contrast, when looking at adhesions as the endpoints, early second-look laparoscopy has been shown to reduce the presence of adhesions at the time of a “third-look” procedure.109 Additionally, reduced rates of ectopic pregnancy have been reported in women having second-look laparoscopies.110 If second-look laparoscopy is to be performed for assessment and possible management of postoperative adhesions, Swolin111 recommended that it be done early (6 to 8 weeks) to improve the possibility of lysis of postoperative adhesions. Subsequently, Raj and Hulka112 examined second-look laparoscopies performed up to 2 years after the initial procedure and demonstrated that bleeding was more common if the procedure was performed more than 12 weeks after surgery or sooner than 2 weeks after surgery. In the former case, bleeding was attributed to increased density and vascularity of the adhesions; in the latter, bleeding was attributed to granulation tissue.
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Table 52-2 Characteristics of an Ideal Antiadhesive Adjuvant Highly efficacious over range of conditions for which it will be utilized High safety profile No interference with tissue healing Easy to handle Easy to deliver Stays where placed Remains in abdominal cavity for sufficient time Will not promote infection Will not interfere with surgical procedure Treats large area Utilizable at open and endoscopic procedures Biosorbable Inexpensive
Table 52-3 Classes of Antiadhesion Agents Fibrinolytic agents Anticoagulants Anti-inflammatory agents Antibiotics Mechanical separation
inflammatory response.114 Hence, a single preventive measure, such as a physical barrier alone applied to one area, may not completely eliminate adhesion development throughout the abdominal cavity. In fact, the antiadhesion material barrier trials have used, as their endpoint, adhesion development at the site of barrier placement rather than at distant sites. Potential Mechanisms for Antiadhesion Barriers
Adjuvant Therapy
There are several different classes of antiadhesion barriers (Table 52-3). Approaches that have been suggested to minimize adhesion development involve one or more of the following mechanisms of action:
In addition to adopting microsurgical principles and optimal surgical techniques to reduce adhesion development, several other approaches have been suggested to help prevent and reduce the severity of adhesion development. Such approaches include the application of intraoperative devices and agents as well as the use of adjuvant medications to prevent adhesions. Table 52-2 includes a list of characteristics possessed by the ideal antiadhesive adjuvant. When reviewing the potential applications of adhesion barriers, it is important to distinguish the prevention of adhesions at the injury site versus other sites. It is not clear whether applying physical barriers to reduce adhesions at site of application can provide protection in areas other than the site of application.113 It has been shown that adhesions can readily develop at uninjured peritoneal sites distant from the midline incision and that a midline laparotomy initiates a generalized peritoneal
1. Reducing fibrin formation (anticoagulants and anti-inflammatory agents such as corticosteroids and nonsteroidal antiinflammatory medications) 2. Enhancing fibrin elimination (peritoneal lavage with fluids, and enzymatic degradation by fibrinolytic agents such as urokinase and recombinant plasminogen activator) 3. Mechanical separation of injured surfaces (peritoneal floatation by lavage fluid and instillation of high molecular-weight liquids and application of mechanical barriers such as Interceed, Gore-Tex Surgical Membrane, and Seprafilm) 4. Indirect mechanisms such as enhancement of intestinal motility to prevent establishment of adhesions and other agents under investigations that modulate mediators of the inflammatory response to peritoneal injury, such as immunomodulator, melatonin, and biodegradable polymers, as well as the use of antibiotics to reduce and eliminate infection.
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Chapter 52 Adhesion Prevention Table 52-4 Examples of Antiadhesion Barriers Oxidized regenerated cellulose (Interceed) FDA approved for laparotomy but not laparoscopy Requires meticulous hemostasis and removal of all irrigant fluids Hyaluronic acid and carboxymethylcellulose (Seprafilm) FDA approved Difficult application by laparoscopy 4% Icodextrin (Adept) FDA approved for laparoscopy but not laparotomy Expanded polytetrafluoroethylene (Gore-Tex surgical membrane) Not approved by the FDA for preventing pelvic adhesions Not biodegradable Requires suturing Ringer’s lactate Not approved by the FDA for preventing adhesions No studies showing human efficacy Dextran 70 (32%) Not FDA approved for preventing adhesions Significant complications such as coagulopathy
Table 52-4 gives some examples of various adjuvants that are generally used to prevent surgical adhesions.115,116 Several substances and materials have been studied and used over the years. These commercial adhesion-reducing substances are relatively expensive, with their cost ranging between $100 and $300 per unit. Although much has been written about use of these agents to prevent adhesion development, too little is known about the economic impact of adhesion-reducing agents on the healthcare system. It is important to stress the fact that a great deal of the available “evidence” involving prevention of adhesions comes from numerous animal studies that have examined various means of preventing postoperative intraperitoneal adhesions, usually in relation to tuboplasties and other infertility-related operations rather than extensive pelvic surgery. In addition, most of the controlled clinical trials of adhesion prevention in humans exist in the infertility literature rather than the gynecologic oncology literature. Although the relevance of these studies to the prevention of adhesions associated with extensive gynecologic surgery is unclear, one may conclude that adjuvants effective in the prevention of adhesions in one clinical setting (infertility surgery) may also be effective in another setting (extensive gynecologic surgery). Such an assumption awaits confirmation but may be false if there are differences in the metabolic, hemostatic, and infectious parameters associated with extensive surgery from those associated with infertility surgery. Moreover, with limited procedures, such as lysis of adhesions, there is no real injury to the underlying structures, as compared with radical operations, in which peritoneal trauma can be extensive. Human trials have not investigated the use of surgical adjuvants in preventing adhesions after radical pelvic surgery; therefore, it remains only speculative that this potential exists. Adhesions may simply represent the normal healing process after peritoneal injury. Indeed, with the degree of tissue destruction associated with radical operations, adhesion development may be physiologic rather than pathologic. Fortunately, animal studies and secondlook laparoscopies, once largely limited to the infertility arena, are now being used in gynecologic oncology research and operative procedures by other surgical specialties.18 Activation of the fibrinolytic system is considered beneficial in the prevention of intra-abdominal adhesions. In the late 19th
century, agents with potential fibrinolytic capacity, including liquor thiosinamine with sodium salicylate117 and oral phosphorus,2 were advocated. Streptokinase and streptodornase were the first agents with proven fibrinolytic properties that were effective in preventing adhesion development in rabbits and rats.118,119 The value of activation of the fibrinolytic system remains unproven in humans. Plasminogen Activator
Tissue plasminogen activator, the main plasminogen activator, has often been studied for prevention of adhesions. Although tPA proved to be effective, the risk of hemorrhage has been the main obstacle to its routine use. Anticoagulants such as heparin are also effective in adhesion prevention, although the use of local heparin in abdominal surgery remains controversial because of the risk of bleeding.120–124 Mechanical Separtion of Injured Surfaces
In the past decade several mechanical barriers have been developed. Membranes of oxidized regenerated cellulose,125,126 modified hyalouronic acid and carboxymethylcellulose, or expanded polytetrafluoroethylene127 were found to prevent the development of adhesions. All three coat the trauma site for the time (>7 days) required for re-epithelialization. Johns has reviewed the literature for the available evidence-based prevention of postoperative adhesions.128 He concluded that level 1 evidence supports the efficacy of three barrier methods for the prevention of postoperative adhesions: Interceed, Seprafilm, and Gore-Tex Surgical Membrane. Adhesions are not eliminated by these barriers, and the main debate is the clinical significance with the level of adhesions prevented. Furthermore, most of the efficacy is at the site of application. All three have limitations. Gore-Tex Surgical Membrane does not resorb and requires surgical removal or must be left in place permanently. Interceed and Seprafilm are biodegradable but also have significant practical limitations. Neither are approved for laparoscopy and their efficacy with this access is unproven. 4% Icodextrim is a recently approved adhesion reduction device that is a cornstarch-derived, water soluble branched glucose polymer. It is a solution that is applied intraperitoneally and is retaired in the peritoneal cavity for 3 to 4 days. Its effect is believed to be by hydroflotation. Hyaluronan
Hyaluronan-based agents have been shown to prevent adhesions after surgery. The potential of these agents to reduce intraabdominal adhesion in abdominal sepsis is a new promising concept. Hyaluronan-based antiadhesive agents, including modified hyaluronan–carboxymethylcellulose bioresorbable membrane and 0.4% hyaluronan solution, have been shown to be effective and safe for clinical application. Only the membrane, however, has been approved by the U.S. Food and Drug Administration (FDA) for use in benign diseases under noninfectious conditions.129 Methods of Unknown Benefit
Hydrofloatation, the use of large-volume isotonic solutions such as normal saline and Ringer’s lactate, has not been directly tested in randomized studies for preventing postsurgical adhesions. However, lack of benefit of crystalloids (and in fact statistically
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Section 7 Reproductive Surgery significant worsening) was demonstrated by a recent metaanalysis.107 Failure of effectiveness of crystalloids is due, at least in part, from the rapid absorption time. Most crystalloids are absorbed at approximately 30 to 60 mL/ hour. However, recent studies have suggested that these crystalloids remain in the peritoneal fluid longer.130 After the instillation of 300 mL of Ringer’s lactate solution, 78 mL was still present in the peritoneal cavity after 48 hours, compared with 30 mL in patients in the control group, in whom no Ringer’s lactate was left.130 By 96 hours there was no difference between the two groups. However, this is still too short a time to have a beneficial effect on adhesion formation. The disturbed equilibrium between fibrin synthesis and degradation leads to persistence of fibrinous adhesions. These will become ingrown with fibroblasts, and subsequent collagen deposition results in the development of permanent fibrous adhesions. Treatment with halofuginone, an inhibitor of collagen type I synthesis, decreases the development of experimentally induced surgical adhesions.131 Clinical trials have not been conducted yet. Anti-inflammatory drugs, including corticosteroids and prostaglandin synthetase inhibitors, have been tested for their ability to prevent adhesions.132–134 Down-regulation of the inflammatory response in this way, however, gave conflicting results. Swolin135 successfully reduced adhesion development in patients by applying intraperitoneal steroids, but others have reported equivocal or even deleterious effects.134 Dextran
Dextran 32% (Hyskon) has been approved by the FDA for uterine distension during operative hysteroscopy. However, randomized trials have shown conflicting results when this product has been used off-label for reduction of adhesions. This, in addition to the allergic reactions developing in some patients, markedly reduced the intra-abdominal use of Hyskon in gynecologic reconstructive surgery.
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Peritoneal adhesions occur in the majority of patients (more than 55%) that have had pelvic surgery. The peritoneum consists of a single layer of mesothelial cells that allows free movement of fluid. There are many events during a surgical procedure such as infection or foreign bodies that can cause adhesions. These events are thought to disturb the fibrinolytic process that is important in adhesion prevention. Mesothelial cells will start to cover a traumatized area of peritoneum by the third day. The predominant cell type in the peritoneal fluid by day 4 to 7 is the macrophage. The fibrin gel matrix that is formed after tissue injury is converted to an adhesion between day 5 and 8 after an injury. Adhesions are associated with infertility, chronic pain, and small-bowel obstrtuction. Adhesions also cause significant problems with subsequent surgical procedures, especially with peritoneal entry. This prolongs operative time. Surgical techniques that decrease adhesion formation are gentle tissue handling, excellent hemostasis, minimizing foreign bodies (including sutures), and decreasing ischemia with irrigation. Crystalloid solutions would not be expected to reduce adhesions because they are rapidly absorbed (35 to 65 mL/hour) before the peritoneal surface has completely repaired and covered with mesothelium, a process that takes up to 8 days.
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1. Bryant T: Clinical lectures on intestinal obstruction. Med Tim Gaz 1:363–365, 1872. 2. Wiseman DM: Adhesion prevention: Past the future. In DiZerega G, DeCherney A, Diamond M, et al (ed). Peritoneal Surgery. New York, Springer, 2000, pp 401–417. 3. Becker JM, Stucchi AF: Intra-abdominal adhesion prevention: Are we getting any closer? Ann Surg 240:202–204, 2004. 4. Hulka JF, Omran K, Berger GS: Classification of adnexal adhesions: A proposal and evaluation of its prognostic value. Fertil Steril 30:661–665, 1978. 5. Diamond MP: Surgical aspects of infertility. In Sciarra JJ. Gynecology and Obstetrics Philadelphia, Harper and Row, 2004. 6. Weibel MA, Majno G: Peritoneal adhesions and their relation to abdominal surgery: A postmortem study. Am J Surg 126:345–353, 1973. 7. Menzies D, Ellis H: Intestinal obstruction from adhesion: How big is the problem? Ann R Coll Surg Engl 72:60–63, 1990. 8. Ellis H: The clinical significance of adhesions: Focus on intestinal obstruction. Eur J Surg Suppl 577:5–9, 1997. 9. Stovall TG, Elder RF, Ling FW: Predictors of pelvic adhesions. J Reprod Med 34:345–348, 1989. 10. Ray NF, Larsen JW, Stillman RJ, et al: Economic impact of hospitalizations for lower abdominal adhesiolysis in the United States in 1988. Surg Gynecol Obstet 176:271–276, 1993.
11. Al-Jaroudi D, Tulandi T: Adhesion prevention in gynecologic surgery. Obstet Gynecol Surv 59:360–367, 2004. 12. Ray NF, Denton WG, Thamer M, et al: Abdominal adhesiolysis: Inpatient care and expenditures in the United States in 1994. J Am Coll Surg 186:1–9, 1998. 13. Moscowitz I, Wexner S: Contributions of adhesions to the cost of health care. Health Care Financing Administration. MEDPAR Database 1990–1996. In DiZerega G, DeCherney A, Diamond M, et al (eds). Peritoneal Surgery. New York, Springer-Verlag, 2000. 14. Menzies D, Parker M, Hoare R, et al: Small bowel obstruction due to postoperative adhesions: Treatment patterns and associated costs in 110 hospital admissions. Ann R Coll Surg Engl 83:40–46, 2001. 15. Holmdhal L, Riseberg B: Adhesions: Prevention and complications in general surgery. Eur J Surg 163:169–174, 1997. 16. Wilson M: Cost and economics of adhesions. Hosp Med 65:343–347, 2004. 17. Wilson MS, Menzies D, Knight AD, Crowe AM: Demonstrating the clinical and cost effectiveness of adhesion reduction strategies. Colorectal Dis 4:355–360, 2002. 18. Monk BJ, Berman ML, Montz FJ: Adhesions after extensive gynecologic surgery: Clinical significance, etiology, and prevention. Am J Obstet Gynecol 170:1396–1403, 1994.
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45. Saed GM, Diamond MP: Hypoxia-induced irreversible up-regulation of type I collagen and transforming growth factor-β1 in human peritoneal fibroblasts. Fertil Steril 78: 144–147, 2002. 46. Saed GM, Diamond MP: Molecular characterization of postoperative adhesions: The adhesion phenotype. J Am Assoc Gynecol Laparosc 11:307–314, 2004. 47. Saed GM, Diamond MP: Modulation of the expression of tissue plasminogen activator and its inhibitor by hypoxia in human peritoneal and adhesion fibroblasts. Fertil Steril 79:164–168, 2003. 48. Saed GM, Zhang W, Diamond MP: Molecular characterization of fibroblasts isolated from human peritoneum and adhesions. Fertil Steril 75:763–768, 2001. 49. Saed GM, Collins KL, Diamond MP: Transforming growth factors β1, β2 and β3 and their receptors are differentially expressed in human peritoneal fibroblasts in response to hypoxia. Am J Reprod Immunol 48:387–393, 2002. 50. Saed GM, Munkarah AR, Diamond MP: Cyclooxygenase-2 is expressed in human fibroblasts isolated from intraperitoneal adhesions but not from normal peritoneal tissues. Fertil Steril 79:1404–1408, 2003. 51. Myhre-Johnson O, Larsen SB, Astrup T: Fibrinolytic activity in serosal and synovial membranes. Arch Pathol 88:623–630, 1969. 52. Diamond MP, El-Hammady E, Wang R, et al: Regulation of expression of tissue plasminogen activator and plasminogen activator inhibitor-1 by dichloroacetic acid in human fibroblasts from normal peritoneum and adhesions. Am J Obstet Gynecol 190:926–934, 2004. 53. Ivarsson ML, Diamond MP, Falk P, Holmdahl L: Plasminogen activator/ plasminogen activator inhibitor-1 and cytokine modulation by the PROACT System. Fertil Steril 79:987–992, 2003. 54. Robbins GF, Brunschwig A, Foote FW: Deperitonealization: Clinical and experimental observations. Ann Surg 130:466–479, 1949. 55. Buckman RF, Buckman PD, Hufnagel HV, Gervin AS: A physiologic basis for the adhesion-free healing of deperitonealized surfaces. J Surg Res 21:67–76, 1976. 56. Mecke H, Schunke M, Schulz S, Semm K: Incidence of adhesions following thermal tissue damage. Res Exp Med 191:405–411, 1991. 57. O’Leary DP, Coakley JB: The influence of suturing and sepsis on the development of postoperative peritoneal adhesions. Ann R Coll Surg Eng 74:134–137, 1992. 58. Holtz G: Adhesion induction by suture of varying tissue reactivity and caliber. Int J Fertil 27:134–135, 1982. 59. Morgenstern L, Hart M, Lugo D, Friedman NB: Changing aspects of radiation enteropathy. Arch Surg 120:1225–1228, 1985. 60. Soderstrom RM: Preventing adhesions: Electrosurgery—advantages and disadvantages. In diZerega GS, Malinak LR, Diamond MP, Linsky DB (eds). Treatment of Post-Surgical Adhesions. New York, Wiley-Liss, 1990 pp 841–844. 61. Ivarsson M-L, Holmdahl L, Eriksson E, et al: Expression and kinetics of fibrinolytic components in plasma and peritoneum during abdominal surgery. Fibrin Proteo 12:61–67, 1998. 62. Ellis H: The cause and prevention of postoperative intraperitoneal adhesions. Surg Gynecol Obstet 133:497–511, 1971. 63. Almdahl SM, Burhol PG: Peritoneal adhesions: Causes and prevention. Dig Dis 8:37–44, 1990. 64. Ellis H: The hazards of surgical glove dusting powders. Surg Gynecol Obstet 171:521–527, 1990. 65. Down RHL, Whitehead R, Watts JMcK: Do surgical packs cause peritoneal adhesions? Aust NZ J Surg 49:379–382, 1979. 66. Elkins TE, Stovall TG, Warren J, et al: A histologic evaluation of peritoneal injury and repair: Implications for adhesion formation. Obstet Gynecol 70:225–228, 1987. 67. Saxén L, Myllärniemi H: Foreign material and postoperative adhesions. NEJM 279:200–202, 1968. 68. Perry JF, Smith GA, Yonehiro EG: Intestinal obstruction caused by adhesions. Ann Surg 142:810–816, 1955. 69. Barnhill D, Doering D, Remmenga S, et al: Intestinal surgery performed on gynecologic cancer patients. Gynecol Oncol 40:38–41, 1991. 70. Alvarez RD: Gastrointestinal complications in gynecologic surgery: A review for the general gynecologist. Obstet Gynecol 71:533–1540, 1988.
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71. Duffy DM, diZerega GS: Is peritoneal closure necessary? Obstet Gynecol Surv 49:817–822, 1994. 72. Wilkinson C, Enkin M: Peritoneal non-closure at cesarean section. In Neilson J, Crowther C, Hodnett E, Hofmeryr G (eds). Pregnancy and Childbirth Module. Cochrane Database Syst Rev 1998; CD000163. 73. Conolly WB, Stephens FO: Factors influencing the incidence of intraperitoneal adhesions: An experimental study. Surgery 63:976–979, 1968. 74. Ellis H: The etiology of postoperative abdominal adhesions. Br J Surg 50:10–16, 1962. 75. Al-Took S, Platt R, Tulandi T: Adhesion-related small bowel obstruction after gynecologic operations. Am J Obstet Gynecol 180:313–315, 1999. 76. Tulandi T: Peritoneal closure and adhesions. Hum Reprod 17:249–250, 2002. 77. Meyer WR, Grainger DA, DeCherney AH, et al: Ovarian surgery on the rabbit: Effect of cortex closure on adhesion formation and ovarian function. J Reprod Med 36:639–643, 1991. 78. Larsson B, Perbeck L: The possible advantage of keeping the uterine and intestinal serosa irrigated with saline to prevent intra-abdominal adhesions in operations for fertility. An experimental study in rats. Acta Chir Scand Suppl 530:15–18, 1986. 79. Zamir G, Bloom AI, Reissman P: Prevention of intestinal adhesions after laparotomy in a rat model—a randomized prospective study. Res Exp Med (Berl) 197:349–353, 1998. 80. Operative Laparoscopy Study Group: Postoperative adhesion development after operative laparoscopy: Evaluation at early second look procedures. Fertil Steril 55:700–704, 1991. 81. Nagle A, Ujiki M, Denham W, et al: Laparoscopic adhesiolysis for small bowel obstruction. Am J Surg 187:464–470, 2004. 82. Ordonez JL, Dominguez J, Evrard V, Koninckx PR: The effect of training and duration of surgery on adhesion formation in the rabbit model. Hum Reprod 12:2654–2657, 1997. 83. Yesildaglar N, Ordonez JL, Laermans I, Koninckx PR: The mouse as a model to study adhesion formation following endoscopic surgery: A preliminary report. Hum Reprod 14:55–59, 1999. 84. Binda MM, Molinas CR, Mailova K, Koninckx PR: Effect of temperature upon adhesion formation in a laparoscopic mouse model. Hum Reprod 19:2626–2632, 2004. 85. Hazebroek EJ, Schreve MA, Visser P, et al: Impact of temperature and humidity of carbon dioxide pneumoperitoneum on body temperature and peritoneal morphology. J Laparoendosc Adv Surg Tech A 12:355–364, 2000. 86. Molinas CR, Koninckx PR: Hypoxaemia induced by CO2 or helium pneumoperitoneum is a co-factor in adhesion formation in rabbits. Hum Reprod 15:1758–1763, 2000. 87. Molinas CR, Mynbaev O, Pauwels A, et al: Peritoneal mesothelial hypoxia during pneumoperitoneum is a cofactor in adhesion formation in a laparoscopic mouse model. Fertil Steril 76:560–567, 2001. 88. West MA, Hackam DJ, Baker J, et al: Mechanism of decreased in vitro murine macrophage cytokine release after exposure to carbon dioxide: Relevance to laparoscopic surgery. Ann Surg 226:179–190, 1997. 89. Gray RI, Ott DE, Henderson AC, et al: Severe local hypothermia from laparoscopic gas evaporative jet cooling: A mechanism to explain clinical observations. JSLS 3:171–177, 1999. 90. Ott DE: Laparoscopy and tribology: The effect of laparoscopic gas on peritoneal fluid. J Am Assoc Gynecol Laparosc 8:117–123, 2001. 91. Volz J, Koster S, Spacek Z, Paweletz N: Characteristic alterations of the peritoneum after carbon dioxide pneumoperitoneum. Surg Endosc 13:611–614, 1999. 92. Martin DC, Diamond MP, Yussman MA: Laser laparoscopy for infertility surgery. In Sanfillippo J, Levine R (eds). Operative Gynecologic Endoscopy. New York, Springer-Verlag, 1989, pp 211–235. 93. Diamond MP: Assessment of results of laser surgery. In Sutton CJG (ed). Bailliere’s Clinical Obstetrics and Gynecology: Laparoscopic Surgery. London, Bailliere Tindall, 1989, 649–654. 94. Diamond MP: Assessment of results of laparoscopic laser surgery. In Sutton CJG (ed). Lasers in Gynaecology. London, Chapman & Hall Medical, 1992, pp 55–72.
95. Daly DC. Hysteroscopy and infertility. In Sciarra JJ (ed). Gynecology and Obstetrics. Philadelphia, Harper & Row, 1986. 96. Martin DC, Diamond MP: Extended laparoscopic surgery: Comparison of laser and other techniques. Curr Probl Obstet Gynecol Fertil 9, 1986. 97. Daniell JF: The role of lasers in infertility surgery. Fertil Steril 42: 815–823, 1984. 98. Dixon JA: Lasers in surgery. Curr Probl Surg 21:1–65, 1984. 99. Paloyan D: Intestinal problems in gynecologic surgery. In Schiarra JJ (ed). Gynecology and Obstetrics Philadelphia, Harper and Row, 2004. 100. Holtz G, Baker E, Tsai C. Effect of 32% dextran 70 on peritoneal adhesion formation and reformation after lysis. Fertil Steril 33:660–662, 1980. 101. Holtz G, Baker ER: Inhibition of peritoneal adhesion reformation after lysis with 32% dextran 70. Fertil Steril 34:394–395, 1980. 102. Elkins TE, Bury RJ, Ritter JL, et al: Adhesion prevention by solutions of sodium carboxymethylcellulose in the rat: I. Fertil Steril 41:926–928, 1984. 103. Elkins TE, Ling FW, Ahokas RA, et al: Adhesion prevention by solutions of sodium carboxymethylcellulose in the rat: II. Fertil Steril 41:929–932, 1984. 104. Diamond MP, DeCherney AH, Linsky CB, et al: Assessment of carboxymethylcellulose and 32% dextran 70 for prevention of adhesions in a rabbit uterine horn model. Int J Fertil 33:278–282, 1988. 105. Diamond MP, DeCherney AH, Linsky CB, et al: Adhesion reformation in the rabbit uterine horn model: I. Reduction with carboxymethylcellulose. Int J Fertil 33:372–375, 1988. 106. Diamond MP, Nezhat F: Adhesions after resection of ovarian endometriomas. Fertil Steril 59:934–935, 1993. 107. Wiseman DM, Trout JR, Franklin RR, Diamond MP: Meta-analysis of the safety and efficacy of an adhesion barrier (Interceed TC7) in laparotomy. J Reprod Med 44:325–331, 1999. 108. Tulandi T, Falcone T, Kafka I: Second-look operative laparoscopy 1 year following reproductive surgery. Fertil Steril 52:421–424, 1989. 109. Ugur M, Turan C, Mungan T, et al: Laparoscopy for adhesion prevention following myomectomy. Int J Gynaecol Obstet 53:145–149, 1996. 110. Lavy G, Diamond MP, DeCherney AH: Ectopic pregnancy: Its relationship to tubal reconstructive surgery. Fertil Steril 47:543–556, 1987. 111. Swolin K: Electromicrosurgery and salpingostomy long-term results. Am J Obstet Gynecol 1975 121:418–419. 112. Raj SC, Hulka JF: Second-look laparoscopy in infertility surgery: Therapeutic and prognostic value. Fertil Steril 38:325–329, 1982. 113. Becker JM, Dayton MT, Fazio VW, et al: Prevention of postoperative abdominal adhesions by a sodium hyaluronate-based bioresorbable membrane: A prospective, randomized, double-blind multicenter study. J Am Coll Surg 183:297–306, 1996. 114. Reed KL, Fruin AB, Bishop-Bartolomei KK, et al: Neurokinin-1 receptor and substance P messenger RNA levels increase during intraabdominal adhesion formation. J Surg Res 108:165–172, 2002. 115. Diamond MP, DeCherney AH: Pathogenesis of adhesion formation/ reformation: Application to reproductive pelvic surgery. Microsurgery 8:103–107, 1987. 116. Adhesion Study Group: Reduction of postoperative pelvic adhesions with intraperitoneal 32% dextran 70: A prospective, randomized clinical trial. Fertil Steril 40:612–619, 1983. 117. Boys F: The prophylaxis of peritoneal adhesions. A review of the literature. Surgery 11:118–168, 1942. 118. Wright LT, Smith DH, Rothman M, et al: Prevention of postoperative adhesions in rabbits with streptococcal metabolites. Proc Soc Exp Biol Med 75:602–604, 1950. 119. James DCO, Ellis H, Hugh TB: The effect of streptokinase on experimental intraperitoneal adhesion formation. J Pathol Bacteriol 90:279–287, 1965. 120. Lai HS, Chen Y, Chang KJ, Chen WJ: Tissue plasminogen activator reduces intraperitoneal adhesion after intestinal resection in rats. J Formos Med Assoc 97:323–327, 1998.
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129. Reijnen MM, Bleichrodt PJ, van Goor RP: Pathophysiology of intraabdominal adhesion and abscess formation, and the effect of hyaluronan. Br J Surg 90:533–541, 2003. 130. Muzii L, Bellati F, Manci N, et al: Ringer’s lactate solution remains in the peritoneal cavity after laparoscopy longer than expected. Fertil Steril 84:148–153, 2005. 131. Nagler A, Rivkind AI, Raphael J, et al: Halofuginone—an inhibitor of collagen type I synthesis—prevents postoperative formation of abdominal adhesions. Ann Surg 227:575–582, 1998. 132. Siegler AM, Kontopoulos V, Wang CF: Prevention of postoperative adhesions in rabbits with ibuprofen, a nonsteroidal anti-inflammatory agent. Fertil Steril 34:46–49, 1980. 133. Jansen RP: Failure of intraperitoneal adjuncts to improve the outcome of pelvic operations in young women. Am J Obstet Gynecol 153:363–371, 1985. 134. Larsson B: Prevention of postoperative formation, reformation of pelvic adhesions. In Treutner KH, Schumpelick V (eds). Peritoneal Adhesions. Berlin, Springer, 1997, pp 331–334. 135. Swolin K: The effect of a massive intraperitoneal dose of glucocorticoid on the formation of postoperative adhesions: Clinical studies using laparoscopy in patients operated on for extrauterine pregnancy. Acta Obstet Gynecol Scand 46:204–218, 1967.
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Surgery for Male Infertility Peter N. Kolettis
INTRODUCTION Infertility affects at least 15% of all couples, and male factor is involved in approximately half of these cases. Approximately half the men with male factor infertility will have problems that are surgically correctable: 40% of men will have a varicocele and 15% will have an obstruction, including those with a previous vasectomy.1 Treatment of surgically correctable male factors is cost-effective and can spare the female partner invasive procedures and potential complications associated with the use of assisted reproductive technologies.2–4 Detection of surgically correctable problems requires an appropriate male factor evaluation, including a history, physical examination, and at least two semen analyses. Further testing, such as endocrine or genetic testing, may be required, depending on the results of the preliminary evaluation. In addition to diagnosing correctable problems, some men may have significant underlying medical problems diagnosed during their evaluation.5,6 Fertility-related surgery on the male reproductive system is performed for three general purposes: diagnosis (procedures such as testicular biopsy and vasography), correction of anatomic abnormalities such as varicocele and obstruction, and sperm retrieval. This chapter focuses on the indications, techniques, and outcomes for these procedures.
DIAGNOSTIC PROCEDURES Transrectal Ultrasound Transrectal ultrasound is employed to detect abnormalities of the prostate, seminal vesicles, and ejaculatory ducts. Azoospermic men with low semen volume (<1 mL) and at least one palpable vas deferens should be evaluated for ejaculatory duct obstruction with transrectal ultrasound. Ejaculatory duct obstruction is a rare cause of infertility, accounting for less than 1% of cases. Causes include congenital atresia or stenosis; utricular, müllerian, or Wolffian duct cysts; trauma; and infection. A seminal vesicle diameter of greater than 1.5 cm is suggestive of ejaculatory duct obstruction, although there is no definite threshold for making the diagnosis.7–10 A partial form of ejaculatory duct obstruction may to be present in men with low semen volume and severe oligoasthenospermia. According to some investigators, this condition can be detected by transrectal ultrasound. However, no precise criteria for diagnosing partial ejaculatory duct obstruction is available, and currently this condition is considered investigational.7
Testis Biopsy The indications for a diagnostic testis biopsy are azoospermia with at least one palpable vas deferens.10–12 It must first be verified that the patient is indeed azoospermic by centrifuging the sample, resuspending the pellet, and repeating the microscopic examination.13 The primary purpose of a testis biopsy is to differentiate obstructive from nonobstructive azoospermia. Pathologic analysis should be performed to analyze the pattern of sperm production and to rule out intratubular germ cell neoplasia, which may occur in 0.4% to 1.1% of infertile men.10 Fixatives such as Bouin’s or zinc formalin allow for maintenance of the testicular architecture for pathologic examination. A diagnostic classification system devised by Levin is useful in describing the pattern of sperm production.14 In the setting of azoospermia, more than 20 mature spermatids per tubule on histologic examination would be consistent with a sperm concentration of 10 million/mL, suggesting obstruction.15 The technique of diagnostic testis biopsy is straightforward. It can be performed through a small scrotal incision with local, regional, or general anesthesia on an outpatient basis. Delivery of the testis is usually not required for a standard biopsy. A biopsy can also be performed percutaneously with a biopsy gun or by fine-needle aspiration, although fewer tubules are obtained this way.16,17 To avoid injury to significant branches of the testicular artery, the biopsies should be taken from the medial or lateral aspect of the upper pole.18 If the testes are symmetric, a unilateral biopsy is sufficient to document obstruction. Bilateral biopsies are more important when attempting to maximize the chances for sperm retrieval.19 Many clinicians believe that isolated diagnostic biopsy is rarely indicated. In cases of suspected obstruction (characterized by normal size testes, normal follicle-stimulating hormone [FSH] level, and indurated or distended epididymis), bilateral biopsies can be analyzed intraoperatively for the presence of sufficient numbers of sperm. Then vasography and microsurgical reconstruction can be performed at the same time. In cases where nonobstructive (small testes, elevated FSH, flat epididymis) azoospermia is suspected, sperm retrieval with cryopreservation can be planned and carried out at the same time.
Vasography The purpose of a vasogram is to assess the patency of the vas deferens. The indications for vasography are azoospermia, a normal FSH, a testis biopsy with normal spermatogenesis, and at least one palpable vas deferens.10,12
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Section 7 Reproductive Surgery Virtually all vasal obstructions are iatrogenic. Vasal obstruction can be encountered after inguinal hernia repair or orchidopexy, retroperitoneal surgery such as renal transplantation and, of course, vasectomy. Vasography is not routinely necessary at the time of vasectomy reversal, however. Azoospermic men with normal semen volume, normal spermatogenesis on a testis biopsy, palpable vasa, and no history of inguinal, scrotal, or retroperitoneal surgery will most likely have epididymal obstruction. Vasography can be performed with either a hemivasotomy or a puncture technique and should be performed only at the time of a planned reconstruction. The puncture technique is technically more difficult to perform. The advantage of the puncture technique is that it does not require separate closure of the vas deferens.20 In most cases where vasoepididymostomy is performed, however, the surgeon can use the vas deferens at the site of transection for the vas-to-epididymis anastomosis; a separate vasal closure is not required. One should try to preserve as much vasal length as possible. Therefore, the ideal site for the vasogram performed at the time of vasoepididymostomy is at the junction of the straight and convoluted vas. For repair of inguinal vasal obstruction or transurethral resection of the ejaculatory ducts, the vasogram could be performed in the scrotal straight vas at a site proximal to the suspected obstruction. For repair of inguinal vasal obstruction or transurethral resection of the ejaculatory ducts, the puncture technique would therefore have a distinct advantage by eliminating the need for a separate vasal closure. Injection should be performed in the antegrade direction only. Iodinated contrast medium is injected and a plain x-ray is obtained to delineate the vasal anatomy. Alternatively, methylene blue or indigo carmine can be injected and the bladder catheterized. If the urine is blue, then patency of the vas is confirmed. Finally, some surgeons simply inject saline solution in an antegrade fashion and assess the ease of injection. If there is no difficulty with the injection, one can assume that the vas distal to the injection site is patent.10 A normal x-ray vasogram should demonstrate a barely perceptible but patent vasal lumen coursing from the scrotum through the inguinal canal to the pelvis, with filling of the ejaculatory ducts and bladder.
TREATMENT OF ACQUIRED OBSTRUCTION Inguinal Vasal Obstruction
794
Obstruction of the vas deferens can occur after inguinal, scrotal, and retroperitoneal surgery.21 Reconstruction of the retroperitoneal vas is usually not possible secondary to retraction of the distal end, and reconstruction of the inguinal vas is challenging and in some cases not possible. Inguinal vasal obstruction is the most likely diagnosis in men who present with normal-volume azoospermia and a history of bilateral inguinal surgery or unilateral surgery and atrophy or absence of the contralateral testis or ductal system. Before attempting surgical correction, a testis biopsy is performed to confirm normal spermatogenesis, followed by vasography to document the obstruction.
Inguinal vasal reconstruction begins with mobilization of the two ends of the vas deferens followed by a microsurgical anastomosis with either a modified one-layer or formal twolayer technique. Difficulties encountered with inguinal vasal reconstruction stem from the inability to isolate and mobilize the distal (abdominal) end and the dense scarring that occurs, particularly with mesh, after inguinal hernia repairs.22,23 Secondary epididymal obstruction can occur. If sperm are not seen in the vas fluid and the patient remains azoospermic postoperatively, then a secondary epididymal obstruction should be suspected. In this scenario, the vasal obstruction should be corrected first, followed by correction of the epididymal obstruction 6 months later. In cases where there is inguinal vasal obstruction on one side and an atrophic testis with a normal ductal system on the contralateral side, strong consideration should be given to a transseptal or “crossover” vasovasostomy because this is technically less complicated than performing an inguinal dissection and anastomosis. Sperm retrieval and in vitro fertilization with intracytoplasmic sperm injection (IVF/ICSI) should be considered as an alternative.24
Vasectomy Reversal Vasectomy is one of the most popular forms of contraception and as many as 4% to 10% of men who undergo a vasectomy request a reversal.24 This procedure is performed as an outpatient with local, regional, or general anesthesia. Secondary epididymal obstruction can occur; in these cases vasoepididymostomy, rather than vasovasostomy, is required.25 Vasoepididymostomy is significantly technically more demanding than vasovasostomy. Vasovasostomy and vasoepididymostomy are usually performed through bilateral high scrotal incisions. Vasovasostomy
The first step in performing a vasovasostomy is to mobilize the vas deferens proximal and distal to the vasectomy site while maintaining the vasal blood supply. A sufficient length of both the testicular and abdominal ends must be obtained to allow for a tension-free anastomosis. The vas is then transected proximal to the vasectomy site and microscopic examination of the fluid is performed. Microscopic examination of the fluid is important both to decide whether vasoepididymostomy is necessary and to understand the cause of failure if the patient remains azoospermic postoperatively. If the vasal fluid lacks sperm, then vasoepididymostomy should be considered particularly if the fluid is thick and pasty. The vasal anastomoses can be performed with either a modified one-layer technique with 9-0 nylon or a formal twolayer technique with 10-0 and 9-0 nylon (Figs. 53-1 and 53-2).26 With the modified one-layer technique, four to six full-thickness 9-0 nylon sutures are placed with four to six 8-0 or 9-0 nylon sutures in the muscularis in between the full-thickness sutures. In the formal two-layer technique, the vasal mucosa is reapproximated as a separate layer with interrupted 10-0 nylon and the muscularis with 9-0 nylon.27 Vasoepididymostomy
The initial approach for vasoepididymostomy is similar to that for vasovasostomy. If thick, pasty vasal fluid without sperm is
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Chapter 53 Surgery for Male Infertility noted, vasoepididymostomy should be considered. The incisions are extended and the tunica vaginalis is opened to deliver the testis and spermatic cord. Typically, the site of epididymal obstruction can be identified by its distension and bluish brown discoloration. The vas deferens is mobilized distally to allow for sufficient length to reach the epididymis. This can require dissection up to the external ring with extension of the incision superiorly. The epididymis is then explored in a systematic fashion in a proximal direction. Individual single epididymal tubules are opened until sperm are seen on microscopic examination of the fluid. Once sperm are seen, the surgeon knows that he or she is proximal to the obstruction. The vas deferens is then routed behind the cord to lie next to the epididymis and aligned with the epididymal tubule by
placing 9-0 nylon sutures from the tunica of the epididymis to the muscularis of the vas deferens. In the traditional end-to-side technique five to eight 10-0 nylon sutures are placed into the open epididymal tubule and then to the mucosa of the vas deferens. The outer layer of the anastomosis is then completed by anastomosing the remainder of the epididymal tunic to the muscularis of the vas deferens with 9-0 nylon (Fig. 53-3).28 The scrotum is then closed in layers with absorbable suture.29
180°
240°
300°
0°
Figure 53-1 Vasovasostomy; modified one-layer technique. Four to six full-thickness nylon sutures are placed.
Figure 53-2 Vasovasostomy; two-layer technique. The vasal mucosa is reapproximated as a separate layer.
Figure 53-3 Vasoepididymostomy. A single epididymal tubule has been opened and sutured to the mucosa of the vas.
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Section 7 Reproductive Surgery Table 53-1 Results of Microsurgical Vasovasostomy Authors
Year
Cos et al36
1983
Requeda37
1983
Owen and Kapila38
Patency Rate
Pregnancy Rate
87
75%
46%
47
80%
46%
1984
475
93%
82%
Lee39
1986
324
90%
51%
Silber*40
1989
282
91%
81%
Belker et al34
1985
1247
86%
52%
Fox41
1994
103
84%
48%
88% (2044/2330)
62% (1285/2061)
TOTAL
# Patients
2565
*Excluding 44 patients with no sperm in the vasal fluid. Patency and pregnancy rates for the study population of 326 patients were 79% and 70%, respectively.
Table 53-2 Results of Microsurgical Vasoepididymostomy Authors
Year
Fogdestam et al42
1986
Silber43
1989
Schlegel and Goldstein44
1993
Thomas and Howards27
Patency Rate
Pregnancy Rate
41
85%
37%
190
77%
49%
91
70%
27%
1997
153
76%
42%
Matsuda et al45
1994
26
81%
38%
Jarow et al46
1997
131
67%
27%
Takihara47
1998
14
71%
29%
Kim et al48
1998
43
81%
37%
72% (498/689)
38% (264/689)
TOTAL
# Patients
689
Newer techniques for vasoepididymostomy involve intusussception of the epididymal tubule into the lumen of the vas deferens. A triangulation technique with three double-arm 10-0 sutures was described by Berger and a two-suture technique was described by Marmar. With these techniques, the double-arm sutures are placed in the distended epididymal tubule before it is opened. The tubule is opened between the previously placed double-arm sutures and these are then placed in the corresponding position of the mucosa of the vas deferens. The outer layer of the anastomosis is completed with 9-0 nylon sutures from the tunica of the epididymis to the muscularis of the vas deferens. The main advantages of these newer intusussception techniques are that the 10-0 sutures are easier to place in a distended tubule and the intusussception of the epididymis into the lumen of the vas deferens may reduce leakage. Patency may occur sooner than with traditional vasoepididymostomy, but pregnancy data for these newer techniques are generally lacking.30,31 Postoperative Course
796
Postoperatively, the patient is to abstain from intercourse, ejaculating, lifting, straining, or other strenuous activity for 3 weeks. He may shower in 48 hours. A scrotal support is not mandatory but can be worn for the first 3 weeks if the patient desires. The first semen analysis is checked between 4 and 12 weeks postoperatively and every 3 months thereafter. It can take as long as 6 months to see sperm return to the semen after vaso-
vasostomy, and the average time to pregnancy is 1 year.32,33 It is not unusual to see lower sperm concentration and motility with the initial semen analyses, and it may take 3 to 6 months or longer to see the semen parameters reach a plateau. Secondary restenosis of the anastomoses can occur in about 10% of cases with subsequent azoospermia.32,34 Sperm cryopreservation can circumvent this problem, but most men will not need the frozen sperm. After vasoepididymostomy, it can take as long as 1 year to see sperm return to the semen.32 Success Rates
Patency rates for vasovasostomy and vasoepididymostomy range from 75% to 93% and 67% to 85%, respectively. Patency rates depend on the obstructive interval (time since the vasectomy), the quality of the vasal fluid noted at surgery, whether epididymal obstruction is present, and surgical technique. Although vasovasostomy can be performed without an operating microscope, microsurgical technique generally yields superior results.35 Accurate performance of vasoepididymostomy without microsurgery would be essentially impossible. Pregnancy rates for vasovasostomy and vasoepididymostomy range from 46% to 82% and 27% to 49%, respectively27,33,36–48 (Tables 53-1 and 53-2). Pregnancy rates depend on the above variables as well as female factors and other factors such as antisperm antibodies. In the study by the Vasovasostomy Study Group, a group of experienced microsurgeons examined the effect of obstructive
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Chapter 53 Surgery for Male Infertility interval and vasal fluid quality on patency and pregnancy rates. They clearly demonstrated that patency and pregnancy rates were inversely related to the obstructive interval. Patency and pregnancy rates were 97% and 76%, respectively, for obstructive intervals of 3 years or less, 88% and 53% for 3 to 8 years, 76% and 44% for 9 to 14 years, and 71% and 31% for 15 years or greater. Vasal fluid quality, both the gross and microscopic appearance, was also an important prognostic factor. The patency and pregnancy rates for grossly clear fluid were 91% and 49%, repectively, for opalescent (cloudy, but thin and watery) fluid 93% and 59%, for thick/creamy fluid 70% and 45%, and for no fluid 88% and 54%. The patency and pregnancy rates were 94% and 63%, repectively, if motile sperm were present, 90% and 54% for nonmotile sperm, 96% and 50% for mostly sperm heads but some with tails, 75% and 40% for sperm heads only, and 60% and 31% if sperm were absent. Thus, the absence of sperm in the vasal fluid significantly lowers the success rate, but patency and pregnancy can still occur.33 If sperm are absent from the vasal fluid, epididymal obstruction may be present. Some investigators therefore recommend vasoepididymostomy if sperm are absent from the vas fluid, regardless of other factors. In a series of 44 patients with intravasal azoospermia, all patients remained azoospermic postoperatively. It was concluded that vasoepididymostomy should be performed if sperm are absent from the vas fluid.40 In the Vasovasostomy Study Group, the patency and pregnancy rates if sperm were absent in the vas fluid were 60% and 31%, respectively. Because epididymal obstruction is more likely to occur as the obstructive interval increases and thicker vasal fluid is more suggestive of epididymal obstruction, it is possible to apply vasoepididymostomy selectively and still obtain acceptable results. The Vasovasostomy Study Group recommended that vasoepididymostomy be considered if there was thick pasty fluid without sperm and the obstructive interval was 9 years or more.33 In another study, Kolettis and colleagues found that if vasovasostomy were applied in instances of intravasal azoospermia where the obstructive interval was 11 years or less, the patency and pregnancy rates were 80% and 38%, respectively, similar to those for vasoepididymostomy.49
TREATMENT OF OTHER FORMS OF OBSTRUCTION
If epididymal obstruction is suspected based on these clinical clues, the patient should be scheduled for testis biopsy, vasography, and possible bilateral vasoepididymostomy, all of which can be done at the same time. In these cases, the testis biopsy will document normal spermatogenesis. An intraoperative wet preparation of the biopsy will demonstrate the presence of significant numbers of sperm.50 Permanent pathology is required to document the pattern of sperm production. After vasography, a vasoepididymostomy can be performed. If the patient desires, simultaneous sperm retrieval can be carried out at the same time.
Ejaculatory Duct Obstruction Men with low-volume azoospermia, a normal FSH level, and at least one palpable vas deferens should undergo transrectal ultrasound to evaluate for ejaculatory duct obstruction. A seminal vesicle diameter of 1.5 cm or greater suggests ejaculatory duct obstruction, although there is no definitive threshold for making the diagnosis.7,10 A testis biopsy is then performed and can be examined intraoperatively to document normal spermatogenesis. Vasogram
Radiographic confirmation of ejaculatory duct obstruction is traditionally documented with a vasogram. The characteristic finding of ejaculatory duct obstruction is a somewhat dilated vasal lumen with abrupt cessation of the contrast at the ejaculatory ducts without filling of the bladder. If a hemivasotomy technique is used, then the vas deferens should be closed after the ejaculatory duct resection with microsurgical technique with either a formal two-layer or modified one-layer technique.51 Seminal Vesiculography
An alternative method for documentation of ejaculatory duct obstruction is seminal vesiculography, as described by Jarow.46 This approach is familiar to most urologists because it is used for prostate biopsies, a commonly performed office procedure. The seminal vesicle is accessed with transrectal ultrasound. The seminal vesicles can be aspirated, and presence of sperm in the seminal vesicles in an azoospermic man confirms ejaculatory duct obstruction. Once the seminal vesicle is entered, contrast medium is injected and a plain film is obtained. If ejaculatory duct obstruction is present, the contrast will stop abruptly at the level of the ejaculatory ducts and the bladder will not be visualized.52
Epididymal Obstruction Epididymal obstruction can be congenital, postinflammatory, posttraumatic, or related to inspissated secretions. Some men with epididymal obstruction will have a history of trauma or epididymitis. In most other cases there will be no other clear details in the history to identify the cause of the azoospermia. Epididymal obstruction can occur secondary to inspissated secretions in men with Young’s syndrome. This syndrome is characterized by a combination of obstructive azoospermia and chronic sinopulmonary infections in men without cystic fibrosis.10 The typical clinical presentation for a man with bilateral epididymal obstruction is the finding of normal-volume azoospermia, with a palpably normal vas deferens, a normal FSH level, and an indurated or distended epididymis.
Transurethral Resection of the Ejaculatory Ducts If ejaculatory duct obstruction is suspected preoperatively, then the biopsy, vasography (or seminal vesiculography), and ejaculatory duct resection can all be performed at the same time. Preoperative preparation for transurethral resection of the ejaculatory ducts should include broad-spectrum antibiotic prophylaxis to cover urinary and fecal flora and a cleansing enema.24 Once the diagnosis of ejaculatory duct obstruction is confirmed with vasography or seminal vesiculography, the patient should be positioned in the lithotomy position. The resectoscope is then inserted into the urethra and a limited resection just lateral to the verumontanum is performed with cutting current to unroof the ejaculatory ducts.24 Once the ejaculatory duct is entered, there should be a significant efflux or “gush” of fluid.
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Section 7 Reproductive Surgery Confirmation of successful unroofing of the ducts can be facilitated by injection of either methylene blue or indigo carmine through the vasogram site. In this way, when the ejaculatory duct is entered, blue efflux confirms adequacy of the resection. A Foley catheter is placed and removed the next day if the urine is clear.51 Secondary epididymal obstruction can also occur with ejaculatory duct obstruction. The vasal fluid can be examined at the time of vasography. If no sperm are present then secondary epididymal obstruction may also exist. With this scenario, then, correction of the underlying problem would require two procedures: transurethral resection of the ejaculatory ducts with subsequent vasoepididymostomy, further decreasing the chance for success.24 Potential complications include bladder neck, sphincter, or rectal injury. Retrograde ejaculation and epididymitis can also occur. Finally, men can experience significant urinary and ejaculatory symptoms secondary to urinary reflux into the vasa.10,51 Success Rates
The patency rate (sperm returning to the semen) for transurethral resection of the ejaculatory ducts is approximately 50% and the pregnancy rate is approximately 25%.51 Complications are unusual but can be significant. Alternative Procedures
An alternative to transurethral resection of the ejaculatory ducts is balloon dilation of the ejaculatory ducts, carried out via a transrectal approach at the time of seminal vesiculography.51,52 Another alternative to surgical correction of ejaculatory duct obstruction is to circumvent the problem with sperm retrieval and ICSI. With improvement in success rates with ICSI, the chance for pregnancy may be better with this approach.
VARICOCELE A varicocele is the most common identified abnormality noted in a male infertility evaluation, detected in approximately 40% of infertile men.7,53,54 Up to 80% of men with secondary infertility are diagnosed with a varicocele.55 Not all varicoceles cause infertility, however, because 15% of fertile men are found to have a varicocele.53
Pathophysiology
798
A varicocele is caused by dilated internal spermatic veins of the pampiniform plexus. Varicoceles are far more common on the left side, but as many as 20% of infertile men have bilateral varicoceles. The precise pathophysiology of varicocele is not understood, but a varicocele may disrupt spermatogenesis by elevating the scrotal temperature. Varicoceles are graded I through III: Grade I: palpable with Valsalva manuever; grade II: palpable; and grade III: visible through the scrotal skin.56 Men with a varicocele that does not drain in the supine position, one that appears suddenly, or an isolated right-sided varicocele should have abdominal imaging to evaluate for a retroperitoneal mass causing obstruction of the renal vein or vena cava. In the past, it was felt that varicocele size was not important; that is, small varicoceles were considered just as detrimental
as large varicoceles. This led to the concept of a subclinical varicocele; that is, one that can be detected by ultrasound but not by physical examination. More recent data suggest that larger varicoceles are more detrimental than small varicoceles.57 Currently, most investigators do not believe that subclinical varicoceles are significant lesions.7
Indication for Repair The most common indication for varicocele repair is infertility with an abnormal semen analysis. Varicocele correction may also be indicated with infertility with a normal semen analysis and a normal female evaluation in that the varicocele could impair some qualitative function of the sperm and therefore impede a pregnancy. Varicoceles may cause pain and therefore correction may be indicated in this setting as well. Correction in this setting should be done with caution and careful preoperative counseling because it is frequently not possible to pinpoint the cause of scrotal pain. A man with a varicocele who is not attempting a pregnancy but desires to do so in the future represents somewhat of a dilemma. Without having attempted a pregnancy a judgment about his fertility status cannot be made. Even if a semen analysis shows some abnormal parameters, he still may be fertile. Even though there is some evidence that a varicocele can cause deterioration in semen parameters over time, most men with a varicocele are not infertile.58 Despite this, varicocele correction in this setting is reasonable because it can eliminate this as a potential source of infertility in the future. For these reasons, many men with a varicocele who desire fertility in the future elect to have their varicocele corrected. An azoospermic man with a varicocele is problematic. Previous studies demonstrated that about half of the men who underwent repair had motile sperm return to the semen, but natural pregnancies were exceedingly rare.59–61 Thus, the rationale for varicocele correction was to avoid testicular sperm extraction (TESE) and the potential associated complications. Furthermore, some of these men did not have a testis biopsy to rule out excurrent duct obstruction. More recently, a study by Schlegel and coworkers questioned the benefit of varicocele correction in men with nonobstructive azoospermia. At some point postoperatively, 22% of men had sperm on one semen analysis. Only 10% of the men had sufficient motile sperm in the semen for ICSI, and those men who underwent varicocele ligation did not have any greater success rate for sperm retrieval. Thus, this most recent study suggests the value of varicocele ligation for men with nonobstructive azoospermia is limited.62
Surgical and Nonsurgical Correction There are numerous surgical and nonsurgical approaches to varicocele correction. Subinguinal, inguinal, retroperitoneal, and laparoscopic approaches have been described. The microsurgical subinguinal approach has continued to gain popularity.63 This approach can be performed with local anesthesia and allows for isolation of the spermatic cord without opening the external oblique fascia. By not opening the fascia, recovery is quicker and pain is reduced.64 A small transverse incision is made in the groin at or just below the external ring. Scarpa’s fascia is opened and the cord is mobilized free. All
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Chapter 53 Surgery for Male Infertility visible internal spermatic veins are ligated. The testicular arterial branches, lymphatics, and vasal veins are spared.65 Microsurgical technique facilitates the identification of all veins and sparing of the testicular arterial branches and lymphatics. The inguinal approach is most familiar to most urologists. With this approach, an inguinal incision is made down to the external oblique fascia. The fascia is opened in the direction of its fibers and cord is mobilized free. Then all visible veins are ligated. Magnification is useful with this approach because it can facilitate sparing the artery. Some surgeons also use an operating microscope for this approach as well.53 For the subinguinal and inguinal approaches, the use of papaverine, a vasodilator, and a Doppler aid in the identification of the arterial branches. The retroperitoneal or high ligation, or Palomo procedure, involves ligation of the entire cord minus the vas deferens. The incision is made above the internal ring and the cord is ligated proximal to the point where the vas turns medially. Thus, the testicular artery is also ligated during this procedure.65 The remaining arterial supply to the testis comes from the vasal artery and cremasterics. The laparoscopic approach is performed transperitoneally, either with or without sparing of the artery. The most popular nonsurgical approach is radiographic embolization. This is usually performed with a femoral vein puncture with passage of an angiographic catheter up the vena cava, across the left renal vein, and then down the gonadal vein. Then, either coils are placed or alcohol is injected to occlude the veins. In experienced hands, embolization has success rates comparable to surgery.66 Each approach to varicocele ligation has its advantages and disadvantages. The subinguinal approach causes less pain because the external oblique fascia is not opened, allowing for a faster recovery.64 At this level, more veins are encountered and the veins may be smaller, necessitating microsurgery. For these reasons, the operative time may be longer than the inguinal approach. The inguinal approach is faster and more familiar to most urologists and fewer veins are encountered. The retroperitoneal approach is fast but is an unfamiliar approach for most urologists. The recurrence rate may be higher because perforating branches may exit the spermatic cord closer to the testis.24,53 Although there does not appear to be an increased incidence of testicular atrophy with this approach, one could question the intentional ligation of the testicular artery during a fertility procedure. Laparoscopic surgery is one of the most rapidly expanding areas in urology. Laparoscopic varicocele ligation is a relatively straightforward procedure for a surgeon with laparoscopic skills. In many instances, the entire cord is ligated in the retroperitoneum above the internal ring, so this procedure has the same theoretical concerns about sacrificing the testicular artery. Although laparoscopic surgery is considered minimally invasive, laparoscopic varicocele ligation could be considered more invasive because it transforms a subcutaneous procedure into a transperitoneal one. The laparoscopic approach is also more expensive. Embolization is advantageous because it does not require general anesthesia or an incision. It also eliminates the risk of arterial injury. It requires an interventional radiologist with specialized skills and involves manipulation of some major vascular structures. Other risks include radiation exposure, intravenous contrast reactions, and coil migration.66
Success Rates Varicocele treatment is a controversial area in the field of male infertility. Pooled results of several studies demonstrated about a 66% improvement in semen parameters (the definition of improvement can vary between different studies) and a 43% pregnancy rate.56 Controlled studies have yielded conflicting results. A study by Nieschlag and colleagues showed no improvement in pregnancy rates when couples received counseling versus varicocele correction. There are several criticisms of this study. More than half of the couples did not complete the study. The control group was not a true untreated control group in that female factors were optimized and the control group received counseling. Finally, the treatment group actually had a significant improvement in sperm concentration.67 A study by Madgar and colleagues demonstrated that there was a significant difference between varicocele ligation and observation. At 1 year, the treatment group had a pregnancy rate of 60% and the control group had a pregnancy rate of 10%. When the control group was crossed over to treatment their pregnancy rate was 44%. The main criticism of this study is the small number of patients, with only 35 couples studied.65
Complications and Recurrence Rates Complications of varicocele ligation are rare. The most feared complication is injury to the testicular artery with subsequent atrophy. Testicular atrophy is not inevitable, however, after testicular artery injury. In one large series, the incidence of arterial injury was 0.9%, but there were no cases of testicular atrophy.68 Another complication is hydrocele, which presumably results from lymphatic injury. The incidence is about 7% and is probably less common with microsurgical technique.53 Finally, varicoceles can recur or persist in 10% or less of cases after treatment. Varicocele recurrence or persistence is most likely a result of failing to ligate one or more venous branches. The use of microsurgical technique probably reduces the recurrence and persistence rates, but comparing different surgical techniques is difficult because the definition of persistence can vary between studies.
SPERM RETRIEVAL TECHNIQUES The introduction of ICSI has revolutionized the treatment of male infertility. This technique can circumvent even the most severe forms of male factory infertility and requires only one viable sperm per egg retrieved during an IVF cycle. Sperm from any source can be used with this technique, and a new set of procedures emerged solely for the purpose of retrieving sperm from azoospermic men. In addition, testis biopsy, once a strictly diagnostic procedure, can now also be a therapeutic one. When considering sperm retrieval, the most important distinction to be made is between obstructive and nonobstructive azoospermia. Patients with nonobstructive azoospermia have decreased or absent sperm production with a patent ductal system; patients with obstructive azoospermia have normal sperm production and an obstruction at some point distal to the testis. In obstructive azoospermia, sperm retrieval is essentially 100% successful. Also, with obstructive azoospermia, percutaneous office procedures can retrieve sperm with high rates of success,
799
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Obstructive Azoospermia In men with obstructive azoospermia, sperm can be obtained either with open surgery from the testis, vas deferens, or epididymis or percutaneously from the testis or epididymis. There are also isolated reports of percutaneous sperm retrieval from the vas deferens. In general, the choice of technique can vary from one center to the next, and there are advantages to each approach. If sperm retrieval is being performed for men with cystic fibrosis or congenital absence of the vas deferens, then the man and his partner should be tested for cystic fibrosis and the intron-8 poly(T) variant, and appropriate genetic counseling should be provided.69,70 Microepididymal Sperm Aspiration
Microepididymal sperm aspiration (MESA) is performed through a scrotal incision under general or regional anesthesia. Under the operating microscope, the epididymis is explored in a systematic fashion beginning at the most distal aspect. Hemostasis is critical to avoid contamination of the aspirates with red blood cells. Individual epididymal tubules are opened and the fluid is aspirated. The exploration proceeds in a proximal direction until motile sperm are obtained. Once motile sperm are noted, the surgeon continues to aspirate the epididymal fluid until no further motile sperm are obtained. If no motile sperm are found in the most proximal portion of the epididymis, then the efferent ducts, located under the caput of the epididymis, are explored and opened to try to find sperm. If motile sperm cannot be retrieved from one side, then the contralateral side is explored. If motile sperm cannot be obtained from either side, then a testis biopsy can be performed and the tissue cryopreserved. With MESA, the greatest numbers of sperm are retrieved and the sperm are easiest to process and cryopreserve.71 It is usually possible to obtain multiple vials for cryopreservation. Cryopreservation of epididymal sperm does not appear to compromise pregnancy rates with ICSI.72 Because cryopreservation is virtually always possible with MESA samples, the chance that a patient will require a repeat procedure is significantly reduced. This technique, however, is the most invasive and the most expensive and requires microsurgical skills. Percutaneous Epididymal Sperm Aspiration
800
Percutaneous epididymal sperm aspiration (PESA) can be performed in the office with local anesthetic and can allow for retrieval of motile sperm. After administration of local anesthetic, the head of the epididymis is isolated and a fine-gauge butterfly needle is passed percutaneously into the head of the epididymis. Then, negative pressure is employed by pulling back on the syringe handle attached to the needle. Use of a Cameco syringe is helpful for this procedure. In general, fewer sperm are retrieved and cryopreservation is therefore more difficult.71 Because it is a blind procedure, there
is potential for injury to the epididymis that could compromise future attempts at microsurgical reconstruction. If no sperm can be obtained from either epididymis, then percutaneous testicular sperm aspiration can be performed. Testicular Sperm Aspiration
Testicular sperm aspiration (TESA) is the simplest and least invasive procedure to retrieve sperm in obstructive azoospermia. It can be performed with local anesthesia in the office. The testis is isolated and local anesthetic is administered. Then a fine-gauge butterfly needle is passed percutaneously into the testis. Negative pressure is employed by pulling back on the syringe handle attached to the needle. Use of a Cameco syringe is also helpful in TESA.73 Because of the intratesticular arterial anatomy, it is safest to aspirate from the medial or lateral aspect of the upper pole of the testis.18 Testicular sperm aspiration retrieves the smallest number of sperm, and cryopreservation is more difficult with these samples. Testicular sperm can also be obtained with a percutaneous testis biopsy using a biopsy gun. Initially, the blind percutaneous procedures raised concerns about bleeding, but the incidence of significant bleeding is low.
Nonobstructive Azoospermia Although there are isolated reports of successful sperm retrieval with percutaneous techniques, most comparative studies demonstrate superior sperm retrieval rates with open techniques for men with nonobstructive azoospermia.74,75 Before attempting sperm retrieval, it is critical that the man have a thorough clinical and genetic evaluation. All men with nonobstructive azoospermia who are pursuing sperm retrieval should have a karyotype performed. If an abnormality is detected, he and his partner should receive genetic counseling before attempting sperm retrieval.69 Testing for Y chromosome microdeletion is also important, because the results can help predict successful sperm retrieval. In one study, no man with AZFa or AZFb deletions had sperm retrieved from the testes. In contrast, those azoospermic men with AZFc deletions had a 75% chance for successful sperm retrieval.76 Another study also suggested that the type of AZF deletion was important in predicting successful sperm retrieval.77 Standard clinical parameters (i.e., testis size, FSH level) cannot predict success or failure with sperm retrieval.78 Sperm production in nonobstructive azoospermia is usually heterogeneous and may be found only in isolated locations or “pockets” of spermatogenesis. As such, sperm retrieval in nonobstructive azoospermia typically requires multiple biopsies and frequently bilateral biopsies for adequate sampling. Sperm retrieval rates in nonobstructive azoospermia are as high as 77%, but most series demonstrate success rates of approximately 50%.10 Multiple biopsies carry some risk of testicular injury. Two techniques have been recently devised to improve success rates for sperm retrieval in nonobstructive azoospermia and limit the amount of testicular tissue removed. Surgical Techniques Testicular Sperm Extraction
In the technique of Turek, fine-needle mapping is performed. Percutaneous fine-needle aspirations are performed from different regions of the testis to create a “map.” Then at the
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Blood vessels Seminiferous tubles Figure 53-4 An incision is made in the tunica albuginea and the testicle widely opened. This cross-section through the testicle shows the convoluted seminiferous tubules and interstitial tissue. The nonsclerotic tubules are sampled.
time of TESE, those regions where sperm were detected are explored and sampled with open biopsies. In a small series of patients, the sperm retrieval rate was 95% (20/21).79
●
Microdissection
A second technique, microdissection, was introduced by Schlegel. In this procedure, the tunica albuginea is widely opened to expose the testicular parenchyma. Using the operating microscope, a search is carried out for visibly dilated tubules because these are more likely to contain sperm. These areas are sampled and analyzed intraoperatively (Fig. 53-4).80 Collapsed, sclerotic tubules are not sampled. With this technique, a sperm retrieval rate of 63% was obtained and less testicular tissue was removed.81
PEARLS ●
●
●
●
The indications for a diagnostic testis biopsy are azoospermia with at least one palpable vas deferens. The indications for vasography are azoospermia, a normal FSH, normal spermatogenesis on testis biopsy, and at least one palpable vas deferens It can take as long as 6 months to see sperm return to the semen after vasovasostomy, and the average time to pregnancy is 1 year. Patency rates for vasovasostomy and vasoepididymostomy range from 75% to 93% and 67% to 85%, respectively.
●
●
●
● ●
●
●
Pregnancy rates for vasovasostomy and vasoepididymostomy range from 46% to 82% and 27% to 49%, respectively. The typical scenario for a man with bilateral epididymal obstruction is one with normal volume azoospermia, palpably normal vasa, normal FSH, an indurated or distended epididymis, and a normal spermatogenesis on testis biopsy. Men with low-volume azoospermia, a normal FSH, and at least one palpable vas deferens should undergo transrectal ultrasound to evaluate for ejaculatory duct obstruction. The precise pathophysiology of varicocele is not understood, but a varicocele may disrupt spermatogenesis by elevating the scrotal temperature. The most common indication for varicocele repair is infertility with an abnormal semen analysis. However, varicocele treatment is a controversial area in the field of male infertility. Varicoceles can be treated with surgery or with embolization. If sperm retrieval is being performed for men with cystic fibrosis or congenital absence of the vas deferens, the man and his partner should be tested for cystic fibrosis and the intron-8 poly(T) variant and appropriate genetic counseling should be provided. All men with nonobstructive azospermia who are pursuing sperm retrieval should have a karyotype performed. The type of AZF deletion is important in predicting successful sperm retrieval.
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4. Schlegel PN: Is assisted reproduction the optimal treatment for varicocele-associated male infertility? A cost-effectiveness analysis. Urol 49:83–90, 1997. 5. Honig SC, Lipshultz LI, Jarow J: Significant medical pathology uncovered by a comprehensive male infertility evaluation. Fertil Steril 62:1028–1034, 1994. 6. Kolettis PN, Sabanegh ES: Significant medical pathology discovered during a male infertility evaluation. J Urol 166:178–180, 2001.
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7. Sigman M, Jarow JP: Male infertility. In Walsh PC, Retik AB, Vaughan ED, Wein AJ (eds). Campbell’s Urology, 8th ed. Philadelphia, WB Saunders, 2002, pp 1475–1531. 8. Meacham RB, Hellerstein DK, Lipshultz LI: Evaluation and treatment of ejaculatory duct obstruction in the infertile male. Fertil Steril 59:393–397, 1993. 9. Pryor JP, Hendry WF: Ejaculatory duct obstruction in subfertile males: Analysis of 87 patients. Fertil Steril 56:725–730, 1991. 10. Kolettis PN: The evaluation and management of the azoospermic patient. J Androl 23:293–305, 2002. 11. Coburn M, Kim ED, Wheeler TM: Testicular biopsy in male infertility evaluation. In Lipshultz LI, Howards SS (eds). Infertility in the Male, 3rd ed. St Louis, Mosby, 1997, pp 219–248. 12. Nagler HM, Thomas AJ Jr: Testicular biopsy and vasography in the evaluation of male infertility. Urol Clin North Am 14:167–176, 1987. 13. Jaffe TM, Kim ED, Hoekstra TH, Lipshultz LI: Sperm pellet analysis: A technique to detect the presence of sperm in men considered to have azoospermia by routine semen analysis. J Urol 159:1548–1550, 1998. 14. Levin HS: Nonneoplastic diseases of the testis. In Sternberg S (ed). Diagnostic Surgical Pathology, 3rd ed. Philadelphia, Lippincott Williams and Wilkins, 1943–1971, 1999. 15. Silber SJ, Rodriguez-Rigau LJ: Quantitative analysis of testicle biopsy: Determination of partial obstruction and prediction of sperm count after surgery for obstruction. Fertil Steril 4:480–485, 1981. 16. Harrington TG, Schauer D, Gilbert BR: Percutaneous testis biopsy: An alternative to open testicular biopsy in the evaluation of the subfertile man. J Urol 156:1647–1651, 1996. 17. Rosenlund B, Kvist U, Ploen L, et al: Comparison between open and percutaneous needle biopsies in men with azoospermia. Hum Reprod 13:1266–1271, 1998. 18. Jarow JP: Clinical significance of intratesticular arterial anatomy. J Urol 145:777–779, 1991. 19. Plas E, Riedl CR, Engelhardt PF, et al: Unilateral or bilateral testicular biopsy in the era of intracytoplasmic sperm injection. J Urol 162:2010–2013, 1999. 20. Poore RE, Schneider A, DeFranzo AJ, et al: Comparison of puncture versus vasotomy techniques for vasography in an animal model. J Urol 158:464–466, 1997. 21. Sheynkin YR, Hendin BN, Schlegel PN, Goldstein M: Microsurgical repair of iatrogenic injury to the vas deferens. J Urol 159:139–141, 1998. 22. Handelsman DJ: Obstructive azoospermia after a second renal transplant: An avoidable cause of infertility. Aust NZ J Med 14:155–156, 1984. 23. Uzzo RG, Lemack GE, Morrissey MM, Goldstein M: The effects of Marlex mesh on the spermatic cord. J Urol 157(4Suppl):302, 1997. 24. Goldstein M: Surgical management of male infertility and other scrotal disorders. In Walsh PC, Retik AB, Vaughan ED, et al (eds). Campbell’s Urology, 7th ed. Philadelphia, WB Saunders, 1998, pp 1331–1377. 25. Silber SJ: Epididymal extravasation following vasectomy as a cause for failure of vasectomy reversal. Fertil Steril 31:309–315, 1979. 26. Sharlip ID: Microsurgical vasovasostomy. In Thomas AJ, Nagler HM (eds). Atlas of Surgical Management of Male Infertility. New York, Igaku Shoin, 1995, pp 58–59. 27. Thomas AJ, Howards SS: Microsurgical treatment of male infertility. In Lipshultz LI, Howards SS (eds). Infertility in the Male, 3rd ed. St Louis, Mosby, 1997, pp 371–384. 28. Thomas AJ: Vasoepididymostomy. In Thomas AJ, Nagler HM (eds). Atlas of Surgical Management of Male Infertility. New York, Igaku Shoin, 1995, p 67. 29. Thomas AJ Jr: Vasoepididymostomy. Urol Clin N Amer 14:527–538, 1987. 30. Berger RE: Triangulation end to side vasoepididymostomy. Urol 159:1951–1953, 1998. 31. Marmar JL: Modified vasoepididymostomy with simultaneous double needle placement, tubulotomy, and tubular invagination. J Urol 163:483–486, 2000. 32. Matthews GJ, Schlegel PN, Goldstein M: Patency following microsurgical vasoepididymostomy and vasovasostomy: Temporal considerations. J Urol 154:2070–2073, 1995.
33. Belker AM, Thomas AJ Jr, Fuchs EF, et al: Results of 1,469 microsurgical vasectomy reversals by the Vasovasostomy Study Group. J Urol 145:505–511, 1991. 34. Belker AM, Fuchs EF, Konnak JW, et al: Transient fertility after vasovasostomy in 892 patients. J Urol 134:75–76, 1985. 35. Middleton RG, Belker AM: Macrosurgery or microsurgery for vasovasostomy? Cont Urol 55–60, 1995. 36. Cos LR, Valvo JR, Davis RS, Cockett AT: Vasovasostomy: Current state of the art. Urolology 22:567–575, 1983. 37. Requeda E: Fertilizing capacity and sperm antibodies in vasovasostomized men. Fertil Steril 39:197–203, 1983. 38. Owen E, Kapila H: Vasectomy reversal Review of 475 microsurgical vasovasostomies. Med J Aust 140:398–400, 1984. 39. Lee HY: A 2-year experience with vasovasostomy. J Urol 136:413–415, 1986. 40. Silber SJ: Pregnancy after vasovasostomy for vasectomy reversal: A study of factors affecting long-term return of fertility in 282 patients followed for 10 years. Hum Reprod 4:318–322, 1989. 41. Fox M: Vasectomy reversal–microsurgery for best results. Br J Urol 73: 449–453, 1994. 42. Fogdestam I, Fall M, Nilsson S: Microsurgical epididymovasostomy in the treatment of occlusive azoospermia. Fertil Steril 46:925–929, 1986. 43. Silber SJ: Results of microsurgical vasoepididymostomy: Role of epididymis in sperm maturation. Hum Reprod 4:298–303, 1989. 44. Schlegel PN, Goldstein M: Microsurgical vasoepididymostomy: Refinements and results. J Urol 150:1165–1168, 1993. 45. Matsuda T, Horii Y, Muguruma K, et al: Microsurgical epididymovasostomy for obstructive azoospermia: Factors affecting postoperative fertility. Eur Urol 26:322–326, 1994. 46. Jarow JP, Oates RD, Buch JP, et al: Effect of level of anastomosis and quality of intraepididymal sperm on the outcome of end-to-side epididymovasostomy. Urolology 49:590–595, 1997. 47. Takihara H: The treatment of obstructive azoospermia in male infertility—past present and future. Urolology 51(Suppl 5A):150–155, 1998. 48. Kim ED, Winkel E, Orejuela F, Lipshultz LI: Pathological epididymal obstruction unrelated to vasectomy: Results with microsurgical reconstruction. J Urol 160:2078–2080, 1998. 49. Kolettis PN, D’Amico AM, Box LC, Burns JR: Outcomes for vasovasostomy with bilateral intravasal azoospermia. J Androl 24:22–24, 2003. 50. Belker AM, Sherins RJ, Dennison-Lagos L: Simple, rapid staining method for immediate intraoperative examination of testicular biopsies. J Androl 17:420–426, 1996. 51. Schlegel PN: Management of ejaculatory duct obstruction. In Lipshultz LI, Howards SS (eds). Infertility in the Male, 3rd ed. St. Louis, Mosby, 1997, pp 385–394. 52. Jones TR, Zagoria RJ, Jarow JP: Transrectal US-guided seminal vesiculography. Radiology 205:276–278, 1997. 53. Goldstein M, Gilbert BR, Dicker AP, et al: Microsurgical inguinal varicocelectomy with delivery of the testis: An artery and lymphatic sparing technique. J Urol 148:1808–1811, 1992. 54. World Health Organization: The influence of varicocele on parameters of fertility in a large group of men presenting to infertility clinics. Fertil Steril 57:1289–1293, 1992. 55. Gorelick JI, Goldstein M: Loss of fertility in men with varicocele. Fertil Steril 59:613–616, 1193. 56. Pryor JL, Howard SS: Varicocele. Urol Clin North Am 14:499–513, 1987. 57. Steckel J, Dicker AP, Goldstein M: Relationship between varicocele size and response to varicocelectomy. J Urol 149:769–771, 1993. 58. Chehval MJ, Purcell MH: Deterioration of semen parameters over time in men with untreated varicocele: Evidence of progressive testicular damage. Fertil Steril 57:174–177, 1992. 59. Matthews GJ, Matthews ED, Goldstein M: Induction of spermatogenesis and achievement of pregnancy after microsurgical varicocelectomy in men with azoospermia and severe oligoasthenospermia. Fertil Steril 70:71–75, 1998.
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72. Tournaye H, Merdad T, Silber S, et al: No differences in outcome after intracytoplasmic sperm injection with fresh or with frozen–thawed epididymal spermatozoa. Hum Reprod 14:90–95, 1999. 73. Belker AM, Sherins RJ, Dennison-Lagos L, et al: Percutaneous testicular sperm aspiration: A convenient and effective office procedure to retrieve sperm for in vitro fertilization with intracytoplasmic sperm injection. J Urol 160:2058–2062, 1998. 74. Ezeh UI, Moore HD, Cooke ID: A prospective study of multiple needle biopsies versus a single open biopsy for testicular sperm extraction in men with non-obstructive azoospermia. Hum Reprod 13:3075–3080, 1998. 75. Friedler S, Raziel A, Strassburger D, et al: Testicular sperm retrieval by percutaneous fine needle sperm aspiration compared with testicular sperm extraction by open biopsy in men with non-obstructive azoospermia. Hum Reprod 12:1488–1493, 1997. 76. Hopps CV, Mielnik A, Goldstein M, et al: Detection of sperm in men with Y chromosome microdeletions of the AZFa, AZFb and AZFc regions. Hum Reprod 18:1660–1665, 2003. 77. Vogt PH, Edelmann A, Kirsch S, et al: Human Y chromosome azoospermia factors (AZF) mapped to different subregions in Yq11. Hum Mol Genet 5:933–943, 1996. 78. Tournaye H, Verheyen G, Nagy P, et al: Are there any predictive factors for successful testicular sperm recovery in azoospermic patients? Hum Reprod 12:80–86, 1997. 79. Turek PJ, Givens CR, Schriock ED, et al: Testis sperm extraction and intracytoplasmic sperm injection guided by prior fine-needle aspiration mapping in patients with nonobstructive azoospermia. Fertil Steril 71:552–557, 1999. 80. Schlegel PN, Hopps CV: Evaluation of the male in infertility. In Sciarra JJ (ed). Gynecology & Obstetrics, Chicago, Lippincott, Williams & Wilkins, 2002, 365–401. 81. Schlegel PN: Testicular sperm extraction: Microdissection improves sperm yield with minimal tissue excision. Hum Reprod 14:131–135, 1999.
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Index Note: Page numbers followed by f refer to figures; page numbers followed by t refer to tables.
A Abdomen examination of, in infertility evaluation, 514 pregnancy in, 722–723 upper, 118, 119t Abdominal paracentesis, in ovarian hyperstimulation syndrome, 601 Abdominal wall anterior, 115–118, 116f, 117f, 118f blood vessels of, 117, 117f extraperitoneal fascia of, 116 muscles of, 115 nerves of, 116–117 parietal peritoneum of, 116 peritoneal landmarks of, 117–118, 118f rectus sheath of, 115–116 subcutaneous tissue of, 115 transversalis fascia of, 115 posterior, 118–121 blood vessels of, 119–121, 120f muscles of, 119 nerves of, 119, 120f trigger points of, in adolescent, 212 vessels of, 117, 117f laparoscopy-related injury to, 672–673, 672f Abnormal uterine bleeding, 297–308 adenomyosis and, 299 in adolescent, 203–205, 204t algorithm for, 305f anticoagulant therapy and, 299t, 302 in bleeding disorders, 301–302, 303 blood clots with, 300 causes of, 298–302, 298t, 299t coagulopathy and, 299t, 301–302 danazol in, 307 definition of, 297 depot medroxyprogesterone acetate and, 399 desmopressin in, 307 dilation and curettage for, 304–305 ectopic pregnancy and, 298, 298t, 713 emergency treatment of, 304–306 endocervical polyps and, 299 endometrial atrophy and, 299t, 301 endometrial biopsy in, 304 endometrial cancer and, 299 endometrial histology in, 126, 127f endometrial polyps and, 299 endometrial synchronization in, 306 endometritis and, 306 estrogen therapy for, 305–306 evaluation of, 302–304, 302f, 303t, 305f gonadotropin-releasing hormone analogues for, 307 hematologic disease and, 299t, 302 hormone replacement therapy and, 299t, 300
Abnormal uterine bleeding (Continued) hormone replacement therapy in, 307 hysterectomy in, 308 hysteroscopy in, 304. See also Endometrial ablation infection and, 298, 298t, 306 intermenstrual, 297 intrauterine devices and, 408, 408t, 409, 410 intravenous estrogen therapy for, 305–306 laboratory testing in, 303–304, 303t leiomyoma and, 298, 683 levonorgestrel-containing intrauterine system in, 307 medroxyprogesterone in, 306 menstrual calendar for, 302, 302f neoplasms and, 298–299, 298t NSAIDs for, 306, 307 oral contraceptives and, 299t, 300, 395 oral contraceptives for, 306, 306t, 307 ovulation defects and, 299t, 300–301 ovulation induction in, 306–307 patient history in, 302–303, 302f physical examination in, 303 postcoital, 298, 299 postmenopausal, 297 pregnancy and, 298, 298t progestins for, 306, 307 sonohysterography in, 304, 445–446, 445f surgical treatment for, 307–308 terminology for, 297 treatment of, 304–308. See also Endometrial ablation emergency, 305–306, 306t long-term, 306–307 surgical, 307–308 ultrasonography in, 304, 444–445, 445f in von Willebrand’s disease, 301–302, 303, 304 Abortion spontaneous. See also Recurrent pregnancy loss artificial insemination and, 546 clomiphene citrate–ovulation induction and, 553–554 vs. ectopic pregnancy, 714, 715 intrauterine device and, 410, 413 polycystic ovary syndrome and, 218 septate uterus and, 178 tubal, 715 Acanthosis nigricans, 218, 266–268, 268, 514 Acid Tyrode’s solution, 592 Acne hirsutism and, 267 oral contraceptive effects on, 391 polycystic ovary syndrome and, 217 Acrodermatitis enteropathica, 198 Acromegaly, 245, 313–314, 313t Acrosome, 77–78 Acrosome reaction, 81, 103, 584 Actinomyces infection, intrauterine devices and, 411 Activin, 6–7, 25f, 25t, 26, 27f, 27t Activin receptor, 42f, 43
Acupuncture, in menopause, 367 Addison’s disease, 289, 317–319, 318t Adenoma adrenal, 321 pituitary, 243, 244–245, 257, 311–316, 312t amenorrhea and, 243, 244–245, 246 corticotropin-secreting, 314–315, 314t, 315f FSH-secreting, 316 growth hormone–secreting, 313–314, 313t LH-secreting, 316 nonsecretory, 316 prolactin-secreting, 223, 243, 244–245, 257, 312–313 thyrotropin -secreting, 316 Adenomyosis abnormal uterine bleeding and, 299 dyspareunia and, 512–513 histology of, 128–129, 129f hysterosalpingography in, 429, 431f magnetic resonance imaging in, 299, 467, 471f, 472, 472f–474f ultrasonography in, 454 Adhesion(s) intrauterine, 641–647. See also Intrauterine adhesions labial, 197 pelvic, 779–788. See also Pelvic adhesions periadnexal, 568, 705–707, 706f Adhesion barrier lining, in neovagina creation, 764 Adnexal masses, 747–756. See also Fallopian tube(s), disease of; Ovarian cancer; Ovarian cyst(s) diagnostic laparoscopy in, 750–751, 751f differential diagnosis of, 747–748, 747t laparoscopic management of, 752–755, 753f, 754f, 755f preoperative evaluation of, 750, 750t ultrasonography in, 442–443 Adolescents, 201–213. See also Puberty abdominal wall trigger points in, 212 abnormal uterine bleeding in, 203–205, 204t amenorrhea in, 205–207. See also Amenorrhea chronic constipation in, 212 chronic pain in, 211–212, 211t confidentiality and, 191–192 dysmenorrhea in, 201–202, 202f eating disorders in, 207–209, 207t, 208t endometriosis in, 211–212 evaluation of, 159–160 gynecologic examination for, 194–196 equipment for, 195 interval for, 195–196 HEADS questions for, 192, 192t inflammatory bowel disease in, 212 irritable bowel syndrome in, 212 lactose malabsorption in, 212 menorrhagia in, 303 menstrual disorders in, 201–205, 202f, 204t müllerian anomalies in, 212 ovarian torsion in, 209–211, 210f
805
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Adolescents (Continued) patient history from, 159–160 pelvic inflammatory disease in, 212 physical examination of, 160 polycystic ovary syndrome in, 202–203 psychosocial concerns of, 160 sexuality of, 160 transverse vaginal septum in, 179 Adoption, 521 Adrenal gland, 317–323 adenoma of, 321 anatomy of, 317 androgen-secreting tumors of, 266, 269 fetal, 319 hypofunction of, 317–319, 318t incidentaloma of, 322–323, 322t pheochromocytoma of, 321–322, 322t, 355 physiology of, 317 in polycystic ovary syndrome, 221–222 venous sampling from, 269 Adrenal insufficiency, 317–319 clinical manifestations of, 318, 318t diagnosis of, 318, 318t etiology of, 317–318, 318t in pregnancy, 319 secondary, 316, 318 treatment of, 318–319 Adrenalectomy, in Cushing’s disease, 315 Adrenarche, 158f, 159, 159f premature, 164–165 Age bone, in delayed puberty, 166 maternal artificial insemination and, 545 chromosome abnormalities and, 99 motherhood and, 148–149 recurrent pregnancy loss and, 609 Agranuloctyosis, antithyroid agent–induced, 328 Alagille syndrome, 90t Albumin intravenous, in ovarian hyperstimulation syndrome, 599–600 steroid hormone binding to, 8, 9, 22–23 Alcohol osteoporosis and, 372 postmenopausal effects of, 366 premenstrual syndrome and, 340 recurrent pregnancy loss and, 616–617 Alcoholism, vs. Cushing’s syndrome, 320 Aldosterone deficiency of, 319 excess of, 321 Alendronate, in osteoporosis, 379 Allergic reaction artificial insemination and, 546 dextran 70 and, 627 iodine and, 432 Alopecia, 217, 267 Alpha-thalassemia screening, in infertility evaluation, 511, 511t Alprazolam, in premenstrual syndrome, 341 Alternative hypothesis, 141 Alternative splicing, 85–86, 85f Ambiguous genitalia. See Congenital anomalies; Hermaphroditism; Pseudohermaphroditism Amenorrhea, 233–249, 297 classification of, 233, 234t definition of, 233 physiologic. See Menopause; Pregnancy
Amenorrhea (Continued) primary, 165–167, 165t, 205–207, 205t, 206f, 233, 233t, 234–238, 235t androgen insensitivity syndrome and, 165–166, 206–207 evaluation of, 238–239, 239f genital tract abnormalities and, 235t, 236–237 gonadal dysgenesis and, 234–236 gonadotropin-releasing hormone receptor abnormalities and, 237–238 imaging in, 238 isolated gonadotropin deficiency and, 237–238 laboratory evaluation in, 238–239 luteinizing hormone receptor abnormalities and, 238 in Mayer-Rokitansky-Küster-Hauser syndrome, 165, 207. See also Mayer-Rokitansky-KüsterHauser syndrome patient history in, 238 physical examination in, 238 vaginal agenesis and, 176 vaginal atresia and, 180 vaginal smear in, 195 secondary, 233, 233t, 234t, 239–249, 245t acromegaly and, 245 anorexia nervosa and, 241–242, 241t anterior pituitary disorders and, 243–245 autoimmune disease and, 246 bone loss and, 242 bulimia and, 241–242, 241t in Cushing’s disease, 245 in Cushing’s syndrome, 243 in empty sella syndrome, 243 evaluation of, 242, 247–249, 247f exercise-induced, 241 genital tract disorders and, 235t, 246–247 gonadal dysgenesis and, 245–246 hyperandrogenic, 243 hypothalamic, 6, 234t, 239–243, 240t, 241t hysteroscopy in, 249 imaging in, 249 infertility and, 242 intrauterine adhesions and, 247, 450 intrauterine devices and, 408, 408t, 409 laboratory evaluation in, 248 management of, 242–243 patient history in, 242, 248 physical examination in, 248 pituitary adenoma and, 243, 244–245 pituitary apoplexy and, 244 pituitary causes of, 234t, 240, 243–245 polycystic ovary syndrome and, 243. See also Polycystic ovary syndrome post-traumatic hypopituitarism and, 244 postcontraception, 243 postirradiation hypopituitarism and, 244 postpartum pituitary necrosis and, 243–244 premature ovarian failure and, 245–246 progestin challenge test in, 248–249 prolactin-secreting adenoma and, 243 stress-related, 6, 240–241, 240t Aminocaproic acid, in abnormal uterine bleeding, 306 Aminoglutethimide, 557 Amniocentesis, 89–90 Amnion lining, in neovagina creation, 764 Ampiregulin, 60 Anabolic steroids, male infertility and, 527
Analgesia for hysterosalpingography, 432–433 for hysteroscopy, 627 for IUD insertion, 413 for sonohysterography, 450 Anaphylaxis artificial insemination and, 546 iodine allergy and, 432 Anastrozole in endometriosis, 740 ovulation induction with, 557–559, 557t Androgen(s). See also Testosterone adrenal in female, 22 in polycystic ovary syndrome, 220, 221–222, 223 assay of in female, 24, 24t in infertility evaluation, 520 in ovulatory dysfunction, 282–283 cutaneous, 265 exogenous, female pseudohermaphroditism and, 182 fetal, 21 hair growth and, 264–265, 265f, 265t nongenomic actions of, 37–38 ovarian, 9–10, 22 biosynthesis of, 7–8, 7f, 8f, 9–10, 22 metabolism of, 9–10 in polycystic ovary syndrome, 220–221 structure of, 18f skeletal effects of, 372–373 testicular, 22 therapeutic in endometriosis, 739–740 in menopause, 364 Androgen insensitivity syndrome, 92, 235t, 237 amenorrhea in, 165–166, 206–207 evaluation of, 237, 238 male pseudohermaphroditism and, 183, 188 malignancy in, 237 Androgen receptors, 9, 33–34, 37, 37f cutaneous, 265 gene mutations in, 37 ligand binding to, 34–35, 34t Androstenedione, 9, 18f, 22 Anejaculation, 585 Anemia, abnormal uterine bleeding and, 205 Anesthesia for hysteroscopic myomectomy, 631 for hysteroscopy, 627 for sterilization, 424–425 Aneuploidy, 66 recurrent pregnancy loss and, 610 Aneusomy, segmental, 90, 90f Angelman syndrome, 90t, 94, 99 Annexin V, recurrent pregnancy loss and, 614 Anorexia nervosa, 207–209, 207t, 208t amenorrhea and, 241–242, 241t, 277, 280t osteoporosis and, 372 treatment of, 167, 243 Anosmin, 237–238 ANOVA (analysis of variance), 142 Anovulation, 30, 277–285, 277f. See also Polycystic ovary syndrome abnormal uterine bleeding and, 204, 300 in adolescent, 204 androgen levels in, 282–283 classification of, 280, 280t
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Anovulation (Continued) congenital adrenal hyperplasia and, 278, 301 diagnosis of, 279–283, 280t, 282f endometrial polyps and, 299 gonadotropins in, 278, 281–282 gynecologic examination in, 281 hypothalamus in, 277–278 laboratory evaluation in, 281–282 lactation and, 255–256 luteal phase defect and, 278 luteinized unruptured follicle syndrome and, 278 ovarian disorders and, 278 pathophysiology of, 277–279 patient history in, 280–281 physical examination in, 281 progestin challenge test in, 283 prolactin levels in, 281 thyrotropin levels in, 281 treatment of, 283–285 Antiandrogens, in polycystic ovary syndrome, 203, 225–225 Antibiotics in actinomycosis, 411 oral contraceptive interactions with, 395, 395t prophylactic in hysteroscopic myomectomy, 631 in intrauterine device placement, 413 in sonohysterography, 450 Antibodies anticardiolipin, 619 antichlamydial, 435–436 antiendometrial, 736 antinuclear, 614, 619 antiovarian, 289–290 antiphospholipid, 613–614, 619, 619t, 620 antisperm, 531, 540, 545, 546, 568 antithyroid, 326, 614 Anticoagulation abnormal uterine bleeding with, 302 in antiphospholipid antibody syndrome, 620 in thrombophilia, 621 Anticonvulsants, in catamenial epilepsy, 344 Antidepressants in menopause, 364, 364t in premenstrual syndrome, 341–342, 341f Antiestrogens, 36. See also Raloxifene; Tamoxifen Antimüllerian hormone, 58, 96, 96f, 98 after chemotherapy, 486 in in vitro fertilization, 570 Antinuclear antibodies, recurrent pregnancy loss and, 614, 619 Antiphospholipid antibody syndrome, recurrent pregnancy loss and, 613–614, 619, 619t, 620 Antithrombin deficiency, recurrent pregnancy loss and, 615t, 616, 619 Antithyroid agents, in hyperthyroidism, 327–328 Antithyroid antibodies, 326 recurrent pregnancy loss and, 614 Antley-Bixler syndrome, 186 Anxiolytics, in premenstrual syndrome, 341 Aorta, 119, 119t laparoscopy-related injury to, 671–672 Apoplexy, pituitary, 317 Apoptosis corpus luteum, 12 in endometriosis, 733 leiomyoma and, 685–686 oocyte, 64–65
Apoptotic inhibitors, cancer-related fertility preservation and, 488 Appendicitis, menstrual cycle and, 346 Arcuate artery, 123 Arcuate line, 115 Arcus tendineus, 122 Arias-Stella reaction, 127, 128f Aromatase in endometriosis, 737 in ovarian steroidogenesis, 8, 8f, 8t Aromatase inhibitors in endometriosis, 740 in McCune-Albright syndrome, 164 osteoporosis and, 373 ovulation induction with, 557–559, 557t adverse effects of, 559 vs. clomiphene citrate, 558 follicle-stimulating hormone in, 559 Arterial embolization, in leiomyoma, 130, 130f Arthritis, menstrual cycle and, 346 Artificial insemination, 539–546, 541t allergic reaction with, 546 antisperm antibodies and, 546 complications of, 545–546 cost-effectiveness of, 542 counseling for, 546 density gradient centrifugation for, 543 donor, 541–542, 546 ectopic pregnancy and, 546 endometrial thickness and, 545 evaluation for, 540 female factors in, 540, 541t, 545 frequency of, 542 glass wool filtration for, 543 historical perspective on, 539 indications for, 539, 539t, 540–542, 541t infection with, 545 informed consent for, 546 intracervical, 540 intraperitoneal, 540 intratubal, 540 intrauterine, 539–540 legal issues in, 546 male factors in, 540–541, 541t, 544–545 maternal age and, 545 multiple pregnancy and, 546 offspring of, 546 outcomes of, 544–545 partner, 539, 540–541 semen analysis in, 540, 544–545 semen sources for, 539 sperm preparation for, 542–543, 543t sperm washing for, 543 spontaneous abortion and, 546 swim-up techniques for, 543 techniques of, 539–540, 544, 544f timing of, 542 tubal, 540 in unexplained infertility, 541 vasovagal reaction with, 545–546 Asherman’s syndrome. See Intrauterine adhesions Asoprisnil, in leiomyoma, 688, 688f Aspartate, in gonadotropin-releasing hormone secretion, 240 Aspirin, in in vitro fertilization, 573 Assisted hatching, 592 Assisted reproductive technology, 567–578. See also In vitro fertilization Angelman syndrome and, 99
Assisted reproductive technology (Continued) Beckwith-Wiedemann syndrome and, 99 in cervical agenesis, 767 complications of, 597–604 cost of, 602 embryo transfer for, 574–576, 576t ethics and, 153–154 imprinting defects and, 63 indications for, 568–569 multiple pregnancy and, 601–603, 601f, 602t offspring of, 603 oocytes for, 577, 586–589 collection of, 574, 587 evaluation of, 587–589, 588f, 589f in vitro maturation of, 589 ovarian hyperstimulation syndrome with, 597–601. See also Ovarian hyperstimulation syndrome ovarian stimulation for, 571–574. See also Ovulation, induction of patient selection for, 569–571, 569f semen for, 581–586 analysis of, 582–583 collection of, 581–582 septate uterus treatment and, 655 sperm for cryopreservation of, 586 processing of, 584–586 tests of, 583–584 Asthma, premenstrual, 345 Atherosclerosis, in polycystic ovary disease, 223 Athlete. See Exercise Atopic dermatitis, in children, 197 Autoimmune disorders, ovarian failure in, 246, 289–290 Axonotmesis, laparoscopy-related, 667 Azoospermia, 98, 530–531. See also Infertility, male Azoospermia factor, 98, 527
B Balloon catheter for hysterosalpingography, 433 for sonohysterography, 452 Balloon stent, in intrauterine adhesion recurrence prevention, 646 Bardet-Biedl syndrome, 98 Basal body temperature in clomiphene citrate–induced ovulation, 552 in ovulation evaluation, 518, 518f Basic fibroblast growth factor, 27t, 28 in implantation, 111 Bax, 65 Bcl-2, 65 leiomyoma and, 685–686 Bcl-2 gene, 97 Bcl-x, 65 Beckwith-Wiedemann syndrome, 99 Behçet’s disease, 197–198 Beneficence, 147 Beta-thalassemia screening, in infertility evaluation, 511, 511t Betacellulin, 60 Bioidentical steroids, 361 Biopsy blastomere, 592, 593f bone, 376–377
807
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Biopsy (Continued) endometrial, 633 in abnormal bleeding, 304 in cancer, 445, 445f in ovulation evaluation, 519 in recurrent pregnancy loss, 618 ovarian, 292 polar body, 592, 593f sciatic nerve, 742, 742f testicular, 793 Bioresorbable membrane, in intrauterine adhesion recurrence prevention, 646 Birth rate, 508 Bisphosphonates, in osteoporosis, 379 Bladder laparoscopy-related injury to, 675–676, 675t magnetic resonance imaging of, 462, 462f–463f Blastomere, biopsy of, 592, 593f Bleeding. See also Abnormal uterine bleeding hysteroscopy-related, 678 laparoscopy-related, 670–673, 672f transvaginal follicle aspiration and, 603 vaginal, in children, 196–197 Bleeding disorders, abnormal uterine bleeding in, 301–302, 303 Blepharophimosis-ptosis-epicanthus inversus syndrome, 246 Blocking, in experimental design, 137 Blood typing, in infertility evaluation, 516 BMP15 gene, 57, 65 Body mass index infertility and, 509, 513 leiomyoma and, 684 Body piercing, in infertility evaluation, 514–515 Bone(s) androgen effects on, 372–373 biochemical assays of, 376t, 475 biopsy of, 376–377 cortical, 371 dual energy absorptiometry of, 375–376, 375t estrogen effects on, 20–21, 372 loss of. See also Osteoporosis in hypothalamic amenorrhea, 242 lactation and, 373 in McCune-Albright syndrome, 164 oral contraceptive effects on, 391 peak mass of, 371 physiology of, 371 resorption of, 372 trabecular, 371 Bone age, in delayed puberty, 166 Bone mineral density, 371 alcohol and, 372 depot medroxyprogesterone acetate and, 399 exercise and, 372 in hypothalamic amenorrhea, 242 oral contraceptive effects on, 391 in premature ovarian failure, 292, 293 Bone morphogenetic protein 6, 15, 53, 55, 57 Bone remodeling units, 371 Botryoid sarcoma, 198 Bowel. See Large intestine BPEI (blepharophimosis, ptosis, and epicanthus inversus) syndrome, 289 BRCA1 gene, 91 BRCA2 gene, 91
Breast(s) anatomy of, 254–255, 254f benign fibrocystic disease of, 391 cancer of. See Breast cancer cyclic changes in, 255 development of, 158, 158f, 159f, 254, 254t premature, 164 examination of, in infertility evaluation, 514 fibroadenoma of, 391 involution of, 256 oral contraceptive effects on, 391, 394 during pregnancy, 255–256. See also Lactation prenatal, 254 pubertal, 254 Breast cancer depot medroxyprogesterone acetate and, 399 fertility preservation in. See Cancer, fertility preservation in hormone replacement therapy and, 260t, 360, 361t in vitro fertilization after, 490–491 intrauterine device placement and, 412 oral contraceptives and, 394 polycystic ovary syndrome and, 223 tamoxifen therapy in, 446 levonorgestrel-containing IUD with, 409–410 Breastfeeding. See Lactation Broad ligament, 116f, 118f, 124 Bromocriptine in pituitary adenoma, 244–245 in polycystic ovary syndrome, 220 in prolactinoma, 313 Bulimia nervosa, 207–209, 207t, 208t amenorrhea and, 241–242, 241t, 277 Buserelin, 4t in fertility preservation, 487–488, 488t Buspirone, in premenstrual syndrome, 341
C CA-125 in endometriosis, 737 in ovarian cancer, 750, 750t Cabergoline in pituitary adenoma, 245 in prolactinoma, 313 Caffeine premenstrual syndrome and, 340 recurrent pregnancy loss and, 617 Calcitonin, in osteoporosis, 379 Calcium impaired absorption of, 373 in menopause, 365 in osteoporosis, 378 Calcium channel blockers, male infertility and, 529 Campomelic dysplasia, 97, 186 Canavan disease screening, in infertility evaluation, 511, 511t Cancer. See also Breast cancer; Cervical cancer; Endometrial cancer; Ovarian cancer endometriosis and, 738 fertility preservation in, 485–505 apoptotic inhibitors and, 488 assisted reproductive technology and, 490–491 in breast cancer, 485 chemotherapy and, 485–486, 486t gonadotropin-releasing hormone agonists in, 487–488, 488t
Cancer (Continued) fertility preservation in (Continued) in gynecologic cancer, 485, 492 in male, 492–493 oocyte cryopreservation and, 490–491 oral contraceptives and, 488 ovarian tissue cryopreservation and transplantation and, 491, 492t ovarian transposition and, 488–490, 489f patient population and, 485 pharmacologic protection in, 487–488, 488t radiotherapy and, 486–487, 487t polycystic ovary syndrome and, 223 Candidiasis, in adolescent, 195 Cannula, for hysterosalpingography, 433 Capacitation, 81, 102–103 Capase-2, 65 Capnography, in laparoscopy, 669 Carbon dioxide in hysteroscopy, 626 in laparoscopy, 669–670 Carboprost, in hysteroscopic myomectomy, 631–632 Carcinoid, 315, 355 Cardinal ligament, 124 Cardiovascular disease in acromegaly, 314 oral contraceptives and, 392–394, 392t in polycystic ovary syndrome, 222–223 postmenopausal, 358 Cardiovascular system, estrogen effects on, 21 L-Carnitine, in male infertility, 536 Carotid artery, 5f CATCH 22 syndrome, 90t Catecholamines, in pheochromocytoma, 322 Catheter, for artificial insemination, 544, 544f CD56bright cells, 110 Centromere, 86, 87f Centrosome, in fertilization, 107 Cerebral palsy, assisted reproductive technology and, 602 Cervical cancer abnormal bleeding and, 299 fertility preservation in, 492. See also Cancer, fertility preservation in oral contraceptives and, 394 Cervical factor, in infertility evaluation, 519–520 Cervical mucus in infertility evaluation, 520 spermatozoa entry to, 80–81 Cervical stenosis hysterosalpingography and, 433 infertility and, 503, 515 Cervicitis abnormal uterine bleeding and, 298 endocervical polyps and, 299 female infertility and, 497–499, 500, 502–503 Cervicotomy, in hysteroscopic myomectomy, 631 Cervix abnormal deflection of, 515 agenesis of, 765–767 diagnosis of, 765–766, 766f pain control in, 766 surgical treatment of, 766–767 diethylstilbestrol-related anomalies of, 178–179 embryology of, 171–172 hysteroscopy-related injury to, 678, 678t incompetent, recurrent pregnancy loss and, 612 infection of. See Cervicitis in infertility evaluation, 515
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Cervix (Continued) magnetic resonance imaging of, 462, 462f–463f motion tenderness of, 515 pregnancy in, 723 stenosis of hysterosalpingography and, 433 infertility and, 503, 515 ureter relationship to, 121, 121f Cesarean section, magnetic resonance imaging after, 472, 476f Cetrorelix, in in vitro fertilization, 572 Chancroid, female infertility and, 501 Chaperonin, 98 CHARGE association, 186 Chemical agents, for sterilization, 425 Chemical peritonitis, 749 Chemotherapy gonadal effects of, 151–152, 290, 485–486, 486t, 493, 527. See also Cancer, fertility preservation in gonadotropin-releasing hormone agonists with, 487–488, 488t Chest wall lesions, hyperprolactinemia and, 257 Children, 191–198. See also Adolescents atopic dermatitis in, 197 confidentiality and, 191–192 fertility preservation in, 151–152 genital tumors in, 198 gynecologic examination for, 192–195, 193f HEADS questions for, 192, 192t hymenal examination in, 193, 193f, 194 interview with, 191 labial adhesions in, 197 lichen sclerosis et atrophicus in, 197 noninfectious vulvovaginitis in, 196 nonspecific vaginitis in, 196 of older mothers, 149 participatory control by, 193–194 physician communication with, 192–194 pinworms in, 196 psoriasis in, 197 as research subjects, 151–152 sexual abuse of, 196, 197, 198 systemic diseases in, 197–198 vaginal bleeding in, 196–197 vaginoscope for, 195 vulvovaginitis in, 196 Chiroinositol, ovulation induction with, 556 Chlamydia infection abnormal uterine bleeding and, 306 antibody testing for, 435–436 female infertility and, 498–499, 498t, 503, 504, 517 sexual abuse and, 196 treatment of, 498t tubal, 503 Cholelithiasis, somatostatin analogue–induced, 314 Cholesterol, 17–18, 18f oral contraceptive effects on, 392 Chorionic villi, in spontaneous abortion vs. ectopic pregnancy, 714, 715 Chromatin structure assay, for sperm, 584 Chromopertubation, 662, 698 Chromosome(s), 86 abnormalities of, 86–90 male infertility and, 98 maternal age and, 99 numerical, 87, 87f, 88t preimplantation diagnosis of, 99
Chromosome(s) (Continued) abnormalities of (Continued) recurrent pregnancy loss and, 610–611 structural, 87–88, 88f, 89f acrocentric, 87f aneuploid, 66, 610 critical region of, 90 deletion of, 88, 90t duplication of, 88 fluorescent in situ hybridization for, 88–90, 90f inversion of, 88, 89f, 610 metacentric, 87f microdeletion of, 90, 90f nondisjunction of, 86–87, 87f, 88t normal, 86 numerical abnormalities of, 87, 87f, 88t ring, 610 Robertsonian translocation of, 88, 89f, 610 sex. See X chromosome; Y chromosome structural abnormalities of, 87–88, 88f, 89f structure of, 86, 87f submetacentric, 87f telomeres of, 90 translocation of, 88, 88f, 89f, 99, 610 Chronic pain. See also Pain in adolescent, 211–212, 211t pelvic adhesions and, 782 Cigarette smoking leiomyoma and, 684 osteoporosis and, 366 premature ovarian failure and, 290 recurrent pregnancy loss and, 616 Cilia, of fallopian tube, 103–104 Circumflex iliac artery, 117 Climacteric, 355. See also Menopause Clips, for sterilization, 424, 424f Clitoris, in child, 194 Clitoromegaly, 268, 773–775 in infertility evaluation, 515 Clitoroplasty, reduction, 773–775, 773f, 774f, 775f Clomiphene citrate antiestrogenic effect of, 551, 554–555 in male infertility, 536 mode of action of, 551 ovarian cancer and, 560, 604 ovulation induction with, 283, 550–555, 571 antiestrogenic effects of, 551, 554–555 vs. aromatase inhibitors, 558 basal body temperature monitoring of, 552 congenital anomalies and, 553 dose for, 551–552, 552f failure of, 555 hot flashes and, 553 indications for, 551 midluteal progesterone monitoring of, 552–553 monitoring of, 552–553 outcomes of, 553 ovarian cancer and, 560 ovarian hyperstimulation syndrome with, 560. See also Ovarian hyperstimulation syndrome in polycystic ovary syndrome, 554–555 pregnancy loss and, 553–554 pregnancy rates and, 552, 552f side effects of, 553 urinary luteinizing hormone monitoring of, 552 visual disturbances and, 553 pharmacodynamics of, 551 pharmacokinetics of, 551 structure of, 551
Clomiphene citrate challenge test in in vitro fertilization, 570–571 in ovarian reserve evaluation, 520 Clonidine, in menopause, 364 Coagulation, oral contraceptive effects on, 392 Coagulopathy, abnormal uterine bleeding and, 301–302 Coccygeal nerve, 119 Coitus, frequency of, in infertility evaluation, 512, 512f Cold intolerance, in infertility evaluation, 513 Colocolpopoiesis, 764–765 Colon. See Large intestine Colonoscopy, in acromegaly, 314 Colorectal cancer, oral contraceptives and, 391 Comet assay, for sperm, 584 Complementary and alternative therapy, in menopause, 366–367 Completely randomized design, 138, 138t Computed tomography, vs. magnetic resonance imaging, 462 Confidence interval, 140–141 Confidentiality, physician-child, 191–192 Confined placental mosaicism, 95 Confounding variable, 137 Congenital adrenal hyperplasia, 180–182, 184 amenorrhea and, 166 female pseudohermaphroditism in, 180–182, 181f, 187–188 hirsutism in, 266, 268–269 in infertility evaluation, 520 late-onset, 319–320 male pseudohermaphroditism in, 184 ovulatory dysfunction in, 278, 280t, 301 precocious puberty and, 164 Congenital anomalies cervical, 178–180, 765–767, 766f clomiphene citrate–ovulation induction and, 553 DES-related, 178–179 genital, 180–187, 180t, 772–775. See also Congenital adrenal hyperplasia; Pseudohermaphroditism counseling for, 187–188 evaluation of, 186–187 gender assignment and, 772–773 reduction clitoroplasty for, 773–775, 773f, 774f, 775f syndromic, 186 vaginoplasty for, 774 in vitro fertilization and, 603 oral contraceptives and, 394 uterine, 174–188. See also at Uterus vaginal, 174, 175f, 176, 178–180 vas deferens, 525, 526–527, 530, 532 Connexin, in cumulus-oocyte complex, 60 Constipation, in adolescent, 212 Contiguous gene syndrome, 90, 90f, 90t Contingency table, 139, 140, 140t Continuous variable, 137, 139 Contraception. See also Sterilization emergency, 396–397 failure of, 408t implantable, 400 injectable, 399–400 intrauterine. See Intrauterine device (IUD) oral. See Oral contraceptives transdermal, 397–398 vaginal ring, 398 Contrast, for hysterosalpingography, 432, 433
809
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Control, in experimental design, 137 Corona radiata (cumulus cells), 59–60 Corpus luteum development of, 550 involution of, 12 ultrasonography of, 453, 453f Cortical reaction, 106–107 Corticosteroids, in lichen sclerosis et atrophicus, 197 Corticotropin, 6t, 311t adenoma secretion of, 314–315, 314t, 315f deficiency of, 316, 318 ectopic production of, 315 fetal, 319 Corticotropin-releasing hormone (CRH) stimulation test, in Cushing’s syndrome, 315, 315f Corticotropin stimulation test, in adrenal insufficiency, 318 Cortisol excess of, 320. See also Cushing’s syndrome serum, 318 urinary, 223 in Cushing’s syndrome, 315, 315f, 320 Counseling, for premature ovarian failure, 292, 292t Covariation, 137 Cox proportional hazards regression model, 144 Cramping after hysteroscopic myomectomy, 632 after hysteroscopy, 680 Creatinine, in Cushing’s syndrome, 320 Cretinism, 329 Cri du chat syndrome, 90t Crohn’s disease, 197 in adolescent, 212 Cryomyolysis, in leiomyoma, 692 Cryopreservation embryo, 594 slow-rate freeze protocol for, 594 sperm, 586 testicular tissue, 493 vitrification for, 594 Culdocentesis, in ectopic pregnancy, 714 Cumulus oophorus, sperm penetration of, 104–105, 104f Cushing’s disease, 245, 314–315, 314t, 315f Cushing’s syndrome, 314–315, 320–321 amenorrhea in, 243 clinical manifestations of, 314t, 320 diagnosis of, 315f, 320 hirsutism in, 269 vs. polycystic ovary syndrome, 223, 301 preclinical, 323 pregnancy and, 321 Cyclin D2, in folliculogenesis, 59 Cyclin-dependent kinase 1 (Cdk1), 61 Cyclin-dependent kinase 2 (Cdk2), 55 Cyclo-oxygenase in endometriosis, 737 isoforms of, 109 Cyproterone acetate, in hirsutism, 270, 271 Cyst endometrial, transvaginal follicle aspiration and, 604 ovarian. See Ovarian cyst(s) Cystadenocarcinoma, 748–749 Cystadenoma, 748–749 Cystectomy, laparoscopic, 663, 752–755, 753f cyst aspiration in, 754, 755 for endometrioma, 755, 755f intraperitoneal spill in, 754
Cystectomy, laparoscopic (Continued) morcellation in, 754, 754f vs. oophorectomy, 752 pelvic washings in, 752 retrieval bags in, 754, 754f specimen removal in, 753–755, 754f Cystic fibrosis infertility and, 511, 511t, 526–527 preimplantation diagnosis of, 99 screening for, 511, 511t Cystic fibrosis transmembrane conductance regulator (CFTR) gene, congenital vas deferens absence and, 525, 532 Cytochrome P450 enzymes, 18–19, 18t, 19f, 20f Cytokines, 27t, 28 endometriosis and, 733–734, 733t, 736 recurrent pregnancy loss and, 614 Cytotrophoblastic cells, 110–111
D Dalkon Shield, 405–406, 406f Danazol in abnormal uterine bleeding, 307 in endometriosis, 739–740 Davydov procedure, in neovagina creation, 764 DAX1 gene, 97, 173 Decapeptyl, in fertility preservation, 487–488, 488t Decidualization, 110 Dehydroepiandrosterone, 9, 22 in hirsutism, 268 in osteoporosis, 381 Denys-Drash syndrome, 97, 186 Dependent variable, 137 Depot medroxyprogesterone acetate, 399–400 osteoporosis and, 373 Depression vs. Cushing’s syndrome, 320 estrogen in, 340, 340f in polycystic ovary syndrome, 203 Dermatitis, atopic, 197 Dermoid cyst magnetic resonance imaging of, 472, 477f puncture of, 604 rupture of, 749 ultrasonography of, 455, 455f 17,20-Desmolase (lyase) deficiency, 184–185 Desmopressin in abnormal uterine bleeding, 307 in hysteroscopic endometrial ablation, 634 in hysteroscopic myomectomy, 631, 632 Dexamethasone, in adrenal insufficiency, 319 Dexamethasone-suppressible hyperaldosteronism, 321 Dexamethasone suppression test, in Cushing’s syndrome, 315, 315f, 320 Dextran 70, in hysteroscopy, 626–627, 679 Diabetes mellitus male infertility and, 527 malnutrition and, 222 menstrual cycle and, 346 in polycystic ovary syndrome, 222–223 recurrent pregnancy loss and, 611, 620 Diaphragm pelvic, 121–122, 122f respiratory, 119 endometriosis of, 741, 741f urogenital, 122
Diet in dysmenorrhea, 202 premenstrual syndrome and, 340–341 Diethylstilbestrol exposure congenital anomalies with, 175f, 176, 178–179 in vitro fertilization and, 569 hysterosalpingography in, 429, 431f recurrent pregnancy loss and, 612 DiGeorge syndrome, 90f, 90t Dihydrotestosterone, 22 Dilation and curettage in abnormal uterine bleeding, 304–305 in adolescents, 205 in ectopic pregnancy, 714 Dioxin, endometriosis and, 731 Disappearing phenomena, in hysteroscopy, 628 Discrete variable, 137, 139 Discriminatory zone, of β-hCG, 455–456, 713–714 Disomy, uniparental, 94 Disseminated intravascular coagulopathy, hysteroscopy and, 626 Distension media for hysteroscopy, 626–627, 631–632, 678–680 for laparoscopy, 669–670 Distribution (statistics), 139 Diuretics, in premenstrual syndrome, 341 Diverticulum, urethral, 482, 483f DNA fragmentation index, for sperm, 545 DNA methyltransferase 1 oocyte isoform, 63–64 Dopamine in polycystic ovary syndrome, 220 prolactin inhibition by, 312 Dopamine agonists in prolactinoma, 313 side effects of, 313 Double decidual sign, 713 Drosperinone in hirsutism, 270 in premenstrual syndrome, 341 Drugs. See also specific drugs hirsutism with, 267, 268 hot flashes with, 356 hyperprolactinemia with, 256–257, 256t, 312, 313t male infertility and, 527, 529 oral contraceptive interactions with, 395, 395t Dual energy x-ray absorptiometry in hypothalamic amenorrhea, 242 in osteoporosis, 375–376, 375t, 381 in premature ovarian failure, 292 Dysfunctional uterine bleeding, 297–298. See also Abnormal uterine bleeding Dysgerminoma, 132, 132f Dysmenorrhea, 297. See also Premenstrual syndrome in adolescents, 201–202, 201t levonorgestrel-containing IUD and, 409, 410 oral contraceptive effects on, 391 pathogenesis of, 201–202, 202f uterine nerve ablation for, 663 Dyspareunia, in infertility evaluation, 512–513
E Eating disorders, 207–209, 207t amenorrhea and, 208, 241–242, 241t osteoporosis and, 372 Echohysteroscopy. See Sonohysterography
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Ectopic pregnancy, 131, 131f, 711–724 abdominal, 722–723 adnexal findings in, 713 algorithm for, 714–716, 715f artificial insemination and, 546 assisted reproductive technology and, 712 bleeding and, 298, 713 cervical, 723 clinical manifestations of, 712–713 cornual (interstitial), 722 culdocentesis in, 714 diagnosis of, 712, 713–716, 715f dilation and curettage in, 714, 715 epidemiology of, 711–712 etiology of, 711 histology of, 131, 131f in vitro fertilization and, 712 infection and, 711 intrauterine device and, 410–411, 712 laboratory tests in, 713–714 oral contraceptives and, 390 ovarian, 131, 722 pain with, 712, 720–721 pelvic examination in, 713 pelvic inflammatory disease and, 502, 711 persistent, 718 physical examination in, 713 pseudogestational sac and, 456 recurrent, 723, 723t risk factors for, 711–712, 712t rupture of, 712, 713 screening for, 716 serum β-hCG in, 713–714, 715–716, 715f serum progesterone in, 714 vs. spontaneous abortion, 714, 715 treatment of, 716–723 expectant management in, 721–222 fertility and, 723–724, 724t hemodynamic stabilization in, 716 hyperosmolar glucose in, 721 laparoscopy in, 663, 717–718, 717t laparotomy in, 716–717, 717t methotrexate in, 718–721, 719t, 720t. See also Methotrexate outcome of, 723–724, 723t potassium chloride in, 721 salpingectomy in, 717, 718, 723–724, 724t salpingostomy in, 717–718, 718t, 723–724 ultrasonography in, 449, 455–456, 713 Eflornithine, in hirsutism, 227, 270 Ejaculation, retrograde, sperm collection from, 585 Ejaculatory duct obstruction, 797 balloon duct dilation in, 798 seminal vesiculography in, 797 transurethral duct resection in, 797–798 vasography in, 797 Ejaculatory dysfunction infertility and, 527, 540–541, 585 transrectal ultrasonography in, 534, 535f treatment of, 536 Electrocautery, vs. electrosurgery, 676 Electrocoagulation, for sterilization, 425 Electroejaculation, in male infertility, 536, 585 Electrolysis, in hirsutism, 227, 269–270 Electrosurgery, laparoscopic, 676–678, 676t capacitive coupling with, 677 complications of, 677–678 duration of, 677 electrode size for, 677
Electrosurgery, laparoscopic (Continued) energy frequency of, 676 insulation failure with, 677–678 monopolar vs. bipolar, 677 power setting for, 677 spark vs. contact mode of, 677 tissue effects of, 676–677, 677f Embolism gas hysteroscopy and, 626 laparoscopy and, 670 oil, hysterosalpingography and, 435, 435f Embryo assisted hatching of, 592 cryopreservation of, 490, 594 culture of, 592 endometriosis effect on, 736 ethical issues and, 152–154 in vitro, 591–592 implantation of, 107–110 maternal effect genes and, 63–64 oocyte transition to, 63–64 polarity in, 64 preimplantation, 107–108 genetic evaluation of, 592–593, 593f research on, 152–154 transfer of for in vitro fertilization, 111, 574–576, 575f, 576t, 603 ultrasonography in, 448 Embryonal carcinoma, 198 Emphysema, laparoscopy-related, 670 Empty sella syndrome, 243, 317 Endometrial ablation, 307–308, 633–635 complications of, 633 global, 634, 635–638, 636t HerOption Uterine Cryoblation Therapy System for, 636–637, 636t Hydro ThermAblator System for, 636t, 637 hysteroscopic, 634–635 cancer and, 680 complications of, 678–680, 678t, 680t cramping after, 634, 680 electrical setting for, 635 equipment for, 634–635 failure of, 635 first-generation, 634 pregnancy and, 680 rollerball, 634–635 scheduling of, 634 technique of, 635 vasopressin for, 634 Microwave Endometrial Ablation System for, 636t, 637–638 NovaSure Endometrial Ablation System for, 636t, 637 preoperative evaluation for, 633 preoperative preparation for, 634 ThermaChoice UBT System for, 636, 636t Endometrial cancer abnormal uterine bleeding and, 299 diagnosis of biopsy in, 445, 445f endometrial thickness and, 445, 445f sonohysterography in, 445–446, 445f, 446–447 ultrasonography in, 444–445, 445f, 446–447 fertility preservation in, 492. See also Cancer, fertility preservation in hysterosalpingography and, 432
Endometrial cancer (Continued) intrauterine devices and, 409 oral contraceptives and, 390 polycystic ovary syndrome and, 223 polyps and, 299 Endometrioma (ovarian cystic endometriosis), 729, 730, 748 diagnosis of, 737 etiology of, 735, 735f laparoscopic resection of, 755, 755f magnetic resonance imaging of, 478, 479f treatment of, 740 ultrasonography of, 455 Endometriosis, 729–742 in adolescent, 211–212 angiogenic factors in, 733 apoptosis in, 733 aromatase in, 737 CA-125 in, 737 cancer and, 738 classification of, 730, 730f, 731f coelomic metaplasia theory of, 735, 735f cyclo-oxygenase-2 in, 737 cytokines in, 733–734, 733t, 736 deep, 729 diagnosis of, 737–738, 737t diaphragmatic, 741, 741f dioxin and, 731 dyspareunia and, 512–513 extrapelvic, 736, 741–742, 741f genetics of, 734–735, 737 genitourinary, 741–742 histology of, 127–128, 128f, 128t, 729 immune disease and, 733–734, 733t, 738 infertility and, 568, 736–737 interleukins in, 734 laparoscopic fulgarization of, 663 laparoscopic visualization of, 737–738 leiomyoma and, 730 levonorgestrel-containing IUD in, 409 macrophages in, 733–734 magnetic resonance imaging in, 478, 478f, 481f matrix metalloproteinases and, 733 monocyte chemoattractant protein-1 in, 733–734 ovarian. See Endometrioma (ovarian cystic endometriosis) pain in, 119, 512–513, 729, 735, 736–737, 742 treatment of, 738–740, 739t pathophysiology of, 732–735, 732f, 732t, 733t predisposing factors for, 730–732 prevalence of, 729–730 progesterone sensitivity and, 733 prostaglandins in, 737 pulmonary, 736 reactive oxygen species in, 734 rectosigmoid, 741, 741f rectovaginal, 735, 740 recurrence of, 740 scar-related, 736 sciatic nerve, 742, 742f sites of, 735–736 T lymphocytes in, 733 thoracic, 741 transplantation theory of, 732–733, 732f, 732t treatment of, 738–742 androgens in, 739–740 for chronic pelvic pain, 738–740, 739t gonadotropin-releasing hormone agonists in, 739 hysterectomy in, 740
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Endometriosis (Continued) treatment of (Continued) investigative agents in, 740 neurectomy in, 740 progestins in, 739 surgical, 740 in unexplained infertility, 738 types of, 729 ureteral, 736, 741–742 vascular endothelial growth factor in, 733 Endometritis abnormal uterine bleeding and, 298, 306 histology of, 126, 126f, 127f infertility and, 503 Endometrium, 123. See also Endometriosis ablation of. See Endometrial ablation Arias-Stella reaction of, 127, 128f aromatase inhibitor effect on, 558, 559 atrophy of, abnormal uterine bleeding and, 301 biopsy of, 633 in abnormal uterine bleeding, 304 in anovulation, 284 in cancer, 445, 445f in ovulation evaluation, 519 in recurrent pregnancy loss, 618 cancer of. See Endometrial cancer clomiphene citrate effects on, 554 cysts of, transvaginal follicle aspiration and, 604 dating of, 125–126, 125f, 125t, 126f decidualization of, 110 embryonic attachment to. See Implantation histology of, 125–130 in abnormal uterine bleeding, 126, 127f in adenomyosis, 128–129, 129f in endometriosis, 127–128, 128f, 128t in endometritis, 126, 126f, 127f in leiomyoma, 129–130, 129f, 129t, 130f in leiomyosarcoma, 130, 130f, 131t menstrual cycle, 125–126, 125f, 125t, 126f oral contraceptives and, 126, 126f in pregnancy, 126–127, 127f, 128f infection of, abnormal uterine bleeding and, 306 inflammation of. See Endometritis levonorgestrel effects on, 409 magnetic resonance imaging of, 462, 462f–463f pinopodes of, 108, 111 polyps of, 628 abnormal uterine bleeding and, 299 in vitro fertilization and, 569 postmenopausal, 444, 454 pseudoatrophy of, 300 pseudodecidual response of, 126, 126f raloxifene effects on, 300 receptivity of, 107, 108 shearing of, with sonohysterography, 452, 452f tamoxifen effects on, 300, 446 thickness of, 454 artificial insemination and, 545 in in vitro fertilization, 573 in menopausal women, 444, 445, 445f ovarian hyperstimulation and, 448, 449f in premenopausal women, 444 tamoxifen therapy and, 446 ultrasound patterns of, in in vitro fertilization, 573 vascularity of, in in vitro fertilization, 573 Endorphins, menstrual cycle levels of, 6 Enterobius vermicularis infection, 196 Environmental exposures, recurrent pregnancy loss and, 617
Eosin-nigrosin test, for sperm, 583 Epidermal growth factor, 27t, 28 in implantation, 109 Epididymal obstruction, 797, 798 Epididymis microsurgical sperm aspiration from, 585–586 obstruction of, 797, 798 in sperm maturation, 80 sperm storage in, 80 sperm transport in, 79–80 Epigastric artery, 117, 117f, 118f laparoscopy-related injury to, 672–673, 672f Epigastric vein, 117, 117f Epilepsy, catamenial, 344–345 Epiregulin, 60 Erectile dysfunction, 527 Errors, statistical, 141–142 Essure procedure, 425, 426f Estradiol, 1t, 8 assay of, 23–24, 24t biosynthesis of, 19f, 20f, 21–22 in in vitro fertilization, 570, 573–574 in menstrual cycle, 10–11, 10f, 20, 21, 21f metabolism of, 8–9, 21–22 structure of, 18f Estriol, 8 placental, 21 Estrogen(s), 8–9, 20–22. See also Estradiol; Estriol; Estrone assay of, 23–24, 24t biosynthesis of, 7–9, 7f, 8f, 19f, 20f, 21–22 catechol, 9, 22 depression and, 340, 340f leiomyoma and, 685–686, 685f levonorgestrel-containing IUD with, 409 metabolism of, 8–9 nongenomic actions of, 37–38 physiologic role of, 20–21, 21f placental, 319 at puberty, 20 skeletal effects of, 372 structure of, 18f therapeutic abnormal uterine bleeding and, 300 in delayed puberty, 167 in endometriosis, 739 in gonadal dysgenesis, 236 in hirsutism, 270 in hypothyroidism, 326–327 in intrauterine adhesion recurrence prevention, 646 intravenous, in abnormal uterine bleeding, 305–306 in isolated gonadotropin deficiency, 238 in labial adhesions, 197 in menopause, 361–362, 362t in menstrual migraine, 344 in osteoporosis, 378–379, 380 in premature ovarian failure, 246 Estrogen receptors, 8, 33–34, 35–37, 59 gene mutations in, 36, 59 hypothalamic, 3 ligand binding to, 34–35, 34t structure of, 35–36, 35f Estrone, 8, 22 assay of, 23–24, 24t biosynthesis of, 19f, 20f, 21–22 structure of, 18f
Ethics, 147–154 case-based, 148 communitarian, 148 of donor gamete disclosure, 150 of embryo research, 152–154 of fertility preservation, 151–152 of motherhood in advanced age, 148–149 of pediatric research, 151–152 of preimplantation genetic diagnosis, 150–151 principle-based, 147–148 of same-sex parentage, 149–150 of sex selection, 150–151 of stem cell research, 152–154 Etidronate, in osteoporosis, 379 Eumenorrhea, 10, 297. See also Menstrual cycle Exercise amenorrhea and, 241 female athlete triad and, 242 menopause and, 365–366 osteoporosis and, 372 premenstrual syndrome and, 341 Exon, 85–86, 85f Experimental design, 137–139. See also Statistics completely randomized, 138, 138t Latin square, 138 randomized complete block, 138, 138t repeated measures, 138–139, 138t
F Factor V Leiden recurrent pregnancy loss and, 615, 615t, 619 venous thromboembolism and, 393 Falciform ligament, 117 Fall prevention, 378 Fallopian tube(s), 123, 429–430, 430f, 431f adhesions of, 568, 705–707, 706f disease of, 697–707. See also Fallopian tube(s), occlusion of Chlamydia trachomatis infection and, 503 etiology of, 697, 697f, 698t evaluation of, 697–698 falloposcopy in, 698 fimbrioplasty in, 703, 706t hysterosalpingography in, 430–431, 431f, 432f, 697–698 hysteroscopic transcervical cannulation in, 699–700, 700f laparoscopic chromopertubation in, 698 microsurgical resection and anastomosis in, 700, 700t pelvic inflammatory disease and, 697, 697f pregnancy and, 698 salpingectomy in, 703–705 salpingography and catheterization in, 699, 699f, 699t salpingoscopy in, 698 salpingostomy in, 703, 705f, 705t sonohysterosalpingography in, 698 transhydrolaparoscopy in, 698 embryology of, 171–172 histology of in ectopic pregnancy, 131, 131f in infection, 130–131, 131f in tuberculosis, 131–132 hysterosalpingography of, 429–437, 430–431, 431f, 432f, 697–698. See also Hysterosalpingography
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Fallopian tube(s) (Continued) infection of, 130–131, 131f, 503, 510 in infertility evaluation, 516, 516t ligation of. See Sterilization, tubal occlusion of, 697 distal, 703–705, 704f midtubal, 700–703, 700f, 700t, 701f, 702f, 703t proximal, 699–700 oocyte transport in, 103–104 pregnancy in. See Ectopic pregnancy schistosomiasis of, 503 tuberculosis of, 131–132, 503, 510 ultrasonography of, 453, 455 Falloposcopy, 698 vs. hysterosalpingography, 436–437 Falope ring, for sterilization, 423–424, 423f Family history in female infertility evaluation, 511, 511t in male infertility evaluation, 529 Fascia Camper’s, 115 extraperitoneal, 116 Scarpa’s, 115 transversalis, 115 Fecundability, definition of, 507, 507t, 508t Fecundity, definition of, 507–508, 507t Female athlete triad, 242 Femoral nerve, 119 laparoscopy-related injury to, 667–668, 668f Fertility. See also Infertility age-related rates of, 508 in cancer patients, 151–152, 485–505. See also Cancer, fertility preservation in depot medroxyprogesterone acetate and, 399 intrauterine devices and, 409 oral contraceptives and, 394 premature ovarian failure and, 290, 292–293 Fertilization, 101–112, 104f, 105f. See also Implantation centrosome in, 107 cumulus oophorus penetration in, 104–105, 104f historical perspective on, 101–102 in vitro. See In vitro fertilization oocyte activation in, 106–107 oocyte transport in, 103–104 polygynic, 591 polyspermic, 591 sperm transport in, 102–103 spermatozoa-oocyte adhesion in, 104–106, 104f spermatozoa-oocyte membrane fusion in, 104f, 106 Fetus(es) adrenal gland of, 319 androgens of, 21 heart rate of, 330 HIV transmission to, 504 selective reduction of, 560 thyroid gland of, 328–329, 330 ultrasonography of, 449 Fibroblast growth factor, in implantation, 109 Fibroid. See Leiomyoma Fibroma, 134–135, 135f, 750 Filshie clip, 424 Fimbriectomy, 419, 422f Fimbrioplasty, 703, 706t Finasteride in hirsutism, 271 in polycystic ovary syndrome, 225
Fish oil supplementation, in dysmenorrhea, 202 Fitz-Hugh–Curtis syndrome, 498, 498f, 662, 662f Fluorocortisone acetate, in adrenal insufficiency, 318 Fluid overload, hysteroscopy and, 626 Fluid therapy, in ovarian hyperstimulation syndrome, 600–601 Fluorescent in situ hybridization (FISH), 88–90, 90f preimplantation, 593, 593f Fluorescent treponemal antibody absorption (FTA-ABS) test, 499 Fluoride, in osteoporosis, 381 Fluoroquininolone, gonorrhea resistance to, 498 Fluoroscopy in intrauterine adhesion lysis, 645 in septate uterus, 653–654 Flutamide in hirsutism, 271 in polycystic ovary syndrome, 225 FMR-1 gene, 94–95 Folate deficiency, recurrent pregnancy loss and, 615–616, 615t Foley catheter, in intrauterine adhesion recurrence prevention, 646 Follicle-stimulating hormone (FSH), 1t, 4, 6, 311t. See also Luteinizing hormone (LH) activin effects on, 7, 25t, 26 adenoma secretion of, 246, 316 aromatase inhibitors with, in ovulation induction, 559 assay of, 31–32, 32t biosynthesis of, 30–31 after chemotherapy, 486 clomiphene citrate with, in ovulation induction, 557 day 3 levels of, recurrent pregnancy loss and, 611, 618 deficiency of, 316 in delayed puberty, 166 in folliculogenesis, 549–550, 550f follistatin effects on, 7, 25t, 26–27 gene mutations in, 31 in hirsutism, 269 in in vitro fertilization, 569–570, 571 inhibin effects on, 7, 25–26, 25t in male infertility evaluation, 532 in ovarian reserve evaluation, 520 in ovulatory dysfunction, 281–282 physiologic role of, 10, 10f, 11, 12, 30 in polycystic ovary syndrome, 203, 218–219, 222 in premature ovarian failure, 248, 291 progesterone effects on, 9 in puberty, 157, 157f, 158 in secondary amenorrhea, 248 structure of, 30–31, 30f Follicle-stimulating hormone (FSH) receptors, 6, 38–41, 58–59 gene mutations in, 40–41, 59, 246 mechanism of action of, 38–39, 40f structure of, 38, 39f Folliculogenesis, 55–57, 56f, 57f, 549–550, 550f regulation of, 55, 57, 58–59 Follistatin, 7, 25f, 25t, 26–27, 27f Follitropin receptor knockout mice, 59 Food additives, hot flashes and, 356 Foreign body, genital, 194, 196 Fornix, magnetic resonance imaging of, 462, 462f–463f FOXL2 gene, 65, 246
Fracture in female athlete, 372 osteoporotic, 371, 372, 377, 377ff postmenopausal, 357–358 Fragile X syndrome, 94–95, 94t, 245–246, 289 Frame-shift mutation, 86 Frasier syndrome, 97 Frequency table, 139 FSH. See Follicle-stimulating hormone (FSH) FSHR gene, 65 Fundus, 123. See also Uterus
G G0/I0 (glucose-to-insulin) ratio, in polycystic ovary syndrome, 224, 224f Gabapentin, in menopause, 364–365 Galactopoiesis, 254 Galactorrhea evaluation of, 257–259, 258f excessive, 259 imaging in, 259 in infertility evaluation, 514 laboratory tests in, 258 nonphysiologic, 256, 256t patient history in, 258 physical examination in, 258 in primary amenorrhea evaluation, 238 serum prolactin in, 258 treatment of, 259 β1,4-Galactosyltransferase-I, 105–106 Gamete intrafallopian transfer, 567 Gamma-aminobutyric acid, in polycystic ovary syndrome, 220 Ganirelix, in in vitro fertilization, 572 Gap junctions, of cumulus cells, 60 Gas chromatography–mass spectrometry, 23 Gas embolism hysteroscopy and, 626 laparoscopy and, 670 Gastrointestinal tract, laparoscopy-related injury to, 673–675, 675f GDF9 gene, 57 Gene, 86 Genetic counseling, in recurrent pregnancy loss, 619 Genetic disorders, 65 chromosomal, 86–90, 87f, 88f, 88t, 89f germ cell mosaicism in, 95 imprinting in, 93–94 in infertility evaluation, 511, 511t in male infertility, 98 mitochondrial, 93, 93f mosaicism in, 95 multifactorial, 92–93 preimplantation diagnosis of, 98–99 in sex differentiation, 96–98 single-gene, 90–92, 91f, 92f preimplantation diagnosis of, 592–593 premature ovarian failure and, 288 recurrent pregnancy loss and, 610 somatic mosaicism in, 95 trinucleotide repeats in, 94–95, 94t uniparental disomy in, 94 Genetic testing in female infertility evaluation, 511, 511t, 517 in male infertility evaluation, 532 preimplantation, 592–593, 593f
813
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Genitalia female congenital abnormalities of, 180–188, 180t, 772–775. See also Pseudohermaphroditism embryology of, 173, 174f normal anatomy of, 193, 193f male congenital abnormalities of, 182–185 embryology of, 174f examination of, in infertility evaluation, 529–530, 530f Genitofemoral nerve, 119, 120f laparoscopy-related injury to, 668f, 669 Genitoplasty, 187 Genome, 85–86 Genomic imprinting, 63, 93–94 Genomics, 85 Germ cell. See also Oocyte(s); Sperm primordial, 51–54 Germ cell mosaicism, 95 Germinal vesicle, breakdown of, 61 Gestational age, recurrent pregnancy loss and, 610 Gestrinone, in endometriosis, 740 Glucagon stimulation test, in pheochromocytoma, 322 Glucocorticoids in hirsutism, 270 osteoporosis and, 374, 380 Glucose, in ectopic pregnancy treatment, 721 Glucose tolerance test, in polycystic ovary syndrome, 203, 223, 224–225, 224f Glutamate, in gonadotropin-releasing hormone secretion, 240 Gluteal artery, 120f, 121 Gluteal nerves, 119 Glycine, for hysteroscopy, 627, 679 Glycodelin-A, 111 GNAS-1 gene, 164 GnRH. See Gonadotropin-releasing hormone (GnRH) Golgi phase, of spermatogenesis, 77–78 Gonad(s). See also Ovary (ovaries); Testis (testes) development of, 95–97, 96f, 173 abnormalities in, 96–98 dysgenesis of, 97, 185–186 management of, 236 mixed, 185–186, 235 pure, 185, 235–236 streak, 97, 132, 132f, 185 Gonadectomy. See also Oophorectomy in androgen insensitivity syndrome, 207 Gonadoblastoma, 132, 132f Gonadostat, 157 Gonadotrophs. See Follicle-stimulating hormone (FSH); Luteinizing hormone (LH) Gonadotropin-releasing hormone (GnRH), 1–3, 1t, 2f, 28–30, 29f biosynthesis of, 29 in hypothalamic amenorrhea–related infertility, 242 isolated deficiency of, 237–238 measurement of, 30 neuroregulation of, 3, 3t, 219–220, 239–240 physiologic role of, 10, 11, 12, 28–29, 29f in polycystic ovary syndrome, 219–220 in puberty, 157, 157f, 158 pulse frequency of, 3, 3t, 10, 12, 29 structure of, 29, 29f in vitro studies in, 220
Gonadotropin-releasing hormone (GnRH)–I, 1–3, 2f Gonadotropin-releasing hormone (GnRH)–II, 3 Gonadotropin-releasing hormone (GnRH) agonists, 3, 4t cryomyolysis and, 692 in endometriosis, 739 in fertility preservation, 487–488, 488t in hirsutism, 270 in in vitro fertilization, 571–572, 600 in irritable bowel syndrome, 346 in leiomyoma, 130, 687 in menstrual migraine, 344 osteoporosis and, 373 in precocious puberty, 162–163 in premenstrual syndrome, 342, 342f Gonadotropin-releasing hormone (GnRH) antagonists, 4 in abnormal uterine bleeding, 307 in ovarian hyperstimulation syndrome, 600 Gonadotropin-releasing hormone (GnRH) pulse generator, in polycystic ovary syndrome, 219–220 Gonadotropin-releasing hormone (GnRH) receptors, 3–4, 41 abnormalities of, 238 gene mutations in, 42 mechanism of action of, 41, 41f structure of, 41, 41f Gonadotropin-releasing hormone (GnRH) stimulation test, in precocious puberty, 161 Gonorrhea infertility and, 497–498, 498f treatment of, 498t Gore-Tex surgical membrane, in adhesion prevention, 787 Goserelin, 4t in endometriosis, 739 in fertility preservation, 487–488, 488t Granuloma, hysterosalpingography and, 435 Granulosa cell(s) cumulus, 58, 59–60 cyclin D2 effect on, 59 insulin effect on, 222 mural, 6, 58–59, 60 peptide secretion by. See Activin; Follistatin; Inhibin in polycystic ovary syndrome, 222 steroid secretion by. See Estradiol; Estrone Granulosa cell tumor, 134, 134f, 750 Graves’ disease. See Hyperthyroidism Growth, pubertal spurt in, 159, 159f Growth differentiation factor 9, 55, 57 Growth factors, ovarian, 27–28, 27t Growth hormone (GH), 311t adenoma secretion of, 313–314, 313t deficiency of, 316 in gonadal dysgenesis, 236 in osteoporosis, 381 at puberty, 159 recombinant, in precocious puberty, 163 Growth hormone (GH) receptor, 42–43 GTP-binding protein–linked receptor 3, 60 Gubernacular ligaments, 124 Gynecologic examination, in infertility evaluation, 515–516 Gynecologic history, in infertility evaluation, 510–511 Gyromagnetic ratio, 461
H Hair abnormal excess of. See Hirsutism growth cycle of, 263–264 androgens and, 264–265, 265f, 265t Hair follicle, 263–264 HAIRAN (hyperandrogenism, insulin resistance, and acanthosis nigricans) syndrome, 266–267, 514 Hamster egg penetration assay, 584 Hand-foot-genital syndrome, 98 Hanging drop test, for Veress needle placement, 671 Haploinsufficiency, 88 Hashimoto’s thyroiditis, 326 Hazard function, 144 Hazard ratio, 144 Head trauma, amenorrhea and, 244 Headache in infertility evaluation, 513 migraine, 343–344, 357 oral contraceptives and, 394–395 HEADS questions, 192, 192t Heart murmur, gas embolism and, 670 Heart rate, fetal, thyroid disease and, 330 Heat intolerance, in infertility evaluation, 513 Heavy metal exposure, recurrent pregnancy loss and, 617 Height precocious puberty and, 160, 161, 163, 163t pubertal spurt in, 159, 159f Hemangioma, hepatic, 662, 662f Hematocolpos, 179, 180f, 206, 237 Hematosalpinx, 131, 131f Hemoconcentration, in ovarian hyperstimulation syndrome, 598 Hemoperitoneum, in ectopic pregnancy, 714 Heparin abnormal uterine bleeding and, 302 in antiphospholipid antibody syndrome, 620 in thrombophilia, 621 Hepatic nuclear factor 1β, 98 Hepatitis, infertility and, 501, 517 Herbal preparations, in infertility evaluation, 512 Hereditary leiomyomatosis and renal cell cancer complex, 684 Hermaphroditism, 186. See also Pseudohermaphroditism counseling for, 187–188 evaluation of, 186–187 gender assignment in, 187 Hernia, laparoscopy-related, 674–675 HerOption Uterine Cryoblation Therapy System, 636–637, 636t Herpes simplex virus infection, 498t, 500 Hesselbach’s triangle, 117 Heteroplasmy, 93 High-intensity MRI-guided focused ultrasound surgery, in leiomyoma, 691–692, 692f Hirsutism, 263–272 abdominal examination in, 268 acne and, 267 in adolescent, 203 in adrenal tumors, 266 alopecia and, 267 androgen suppression in, 270–271 in congenital adrenal hyperplasia, 266, 268–269 in Cushing’s syndrome, 267, 269 cyproterone acetate in, 271 definition of, 217, 263
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Hirsutism (Continued) dehydroepiandrosterone sulfate in, 268 drug-induced, 267, 268 ethnic variability in, 263, 263t, 268 etiology of, 265–267, 265f evaluation of, 267–269, 281 extent of, 267 family history of, 268 finasteride in, 271 flutamide in, 271 glucocorticoids in, 270 gonadotropin-releasing hormone agonists in, 270 gonadotropins in, 269 in HAIRAN syndrome, 266–267 in hyperprolactinemia, 267, 269 in hyperthecosis, 266 vs. hypertrichosis, 263, 263t, 268 idiopathic, 265 imaging in, 269 in infertility evaluation, 514 insulin sensitizers in, 270–271 laboratory tests in, 268–269 menstrual history in, 267–268 nonpharmacologic treatment of, 227, 269–270 onset of, 267 oral contraceptives in, 270 in ovarian tumors, 266 patient history in, 267–268 pelvic examination in, 268 peripheral androgen blockade in, 271 physical examination in, 268 in polycystic ovary syndrome, 217, 227, 265–266, 265f prevalence of, 263, 263t spironolactone in, 271 testosterone level in, 268 treatment of, 227, 269–271, 284 virilization and, 267, 268 weight and, 268 Histrelin, 4t in precocious puberty, 162–163 Homeostasis model assessment, in polycystic ovary syndrome, 224–225, 224f Homosexuality, parentage and, 149–150 Hook effect, 33 Hormone replacement therapy. See also Estrogen(s), therapeutic in abnormal uterine bleeding, 307 abnormal uterine bleeding and, 300 breast cancer and, 260t, 360, 361t in delayed puberty, 167 in menopause, 358–362, 359t, 360t, 361t in premature ovarian failure, 246, 293 Hospitalization, in ovarian hyperstimulation syndrome, 601 Hot flashes, 355–357, 356f acupuncture for, 367 clomiphene citrate ovulation induction and, 553 clonidine for, 364 drug-induced, 356 food additives and, 356 gabapentin for, 364–365 hormone therapy for, 360–361 morbidity of, 357 neurologic, 356 in premenstrual syndrome, 340 selective serotonin reuptake inhibitors for, 364, 364t sleep disorders and, 357 in systemic diseases, 355–356
Hot flashes (Continued) treatment of, 361 veralipride for, 365 HOX gene, 109–110 HOXA13 gene, 98 Hulka clip, 424, 424f Human chorionic gonadotropin (hCG) in artificial insemination, 542 discriminatory zone of, 455–456, 713–714 in ectopic pregnancy, 713–714, 715–716, 715f in in vitro fertilization, 571, 576 in implantation, 109 ovulation induction with, 556 Human Fertilization and Embryology Authority law, 149 Human Genome Project, 85–86 Human immunodeficiency virus (HIV) infection fetal, 504 intrauterine device placement and, 412 pregnancy and, 504–505 prevention of, 504–505 Human leukocyte antigens, 613 recurrent pregnancy loss and, 614 Human papillomavirus (HPV) infection, 498t, 500 Huntington disease, 95 Hutterites, 508 Hyaluronan, in adhesion prevention, 787 Hydro ThermAblator System, 636t, 637 Hydrocortisone in adrenal insufficiency, 318 in hirsutism, 270 Hydrofloatation, in adhesion prevention, 787–788 Hydrolaparoscopy, transvaginal, 436 Hydromucocolpos, in transverse vaginal septum, 179 Hydrosalpinges antibiotic effect on, 704–705 histology of, 131, 131f in vitro fertilization and, 568, 569, 703–705 hysterosalpingography in, 430, 430f, 431f treatment of, 703–705 ultrasonography in, 444 17α-Hydroxylase deficiency of, male pseudohermaphroditism and, 184 in polycystic ovary syndrome, 221 11β-Hydroxylase deficiency female pseudohermaphroditism in, 182 hirsutism in, 266 late-onset, 319–320 21-Hydroxylase deficiency, 223 female pseudohermaphroditism in, 180–182, 181f hirsutism in, 266 in infertility evaluation, 520 late-onset, 319–320 17-Hydroxyprogesterone, serum, 223 3β-Hydroxysteroid dehydrogenase, in ovarian steroidogenesis, 18–19, 18t, 19f, 20f 17β-Hydroxysteroid dehydrogenase, 9 deficiency of, 237 male pseudohermaphroditism and, 185 in ovarian steroidogenesis, 18–19, 18t, 19f, 20f 3β-Hydroxysteroid dehydrogenase deficiency female pseudohermaphroditism in, 182 hirsutism in, 266 male pseudohermaphroditism and, 184 Hymen configurations of, 193, 193f, 194 embryology of, 173 imperforate, 179, 180f, 206, 206f, 237
Hymen (Continued) trauma to, 196 Hyperaldosteronism, 321 Hyperandrogenemia, 235t in polycystic ovary syndrome, 220–222, 221f Hyperandrogenism functional, 278 in infertility evaluation, 520 Hyperandrogenism, insulin resistance, and acanthosis nigricans (HAIRAN) syndrome, 266–267, 514 Hypercortisolism, 320. See also Cushing’s syndrome Hyperemesis gravidarum, 329, 329t Hyperhomocysteinemia, recurrent pregnancy loss and, 615–616, 615t, 619, 621 Hyperinsulinemia androgen excess and, 266 in polycystic ovary syndrome, 203, 221–222 Hyperparathyroidism, osteoporosis and, 373 Hyperprolactinemia, 243, 256–259, 312–313, 313t. See also Prolactinoma in chest wall lesions, 257 clinical manifestations of, 256 drug-related, 256–257, 256t etiology of, 256–257, 256t hirsutism and, 269 hypothalamic tumors and, 257 hypothyroidism and, 257 menstrual cycle and, 3t ovulatory dysfunction and, 278, 280–281, 280t, 301, 519 pituitary adenoma and, 223, 243, 244–245, 257 recurrent pregnancy loss and, 611, 620 treatment of, 244–245, 259 Hyperthecosis, 133, 133f hirsutism and, 266 Hyperthyroidism, 327–328, 327t clinical features of, 327, 327t fertility and, 324–325 fetal, 330 in infertility evaluation, 513–514 laboratory evaluation of, 327 ovulatory dysfunction and, 278, 280t postpartum, 330 pregnancy and, 329–330, 329t subclinical, 325 treatment of, 327–328 Hypertrichosis, vs. hirsutism, 263, 263t, 268 Hypo-osmotic swelling test, for sperm, 545, 583 Hypoaldosteronism, 319 Hypoestrogenemia. See also Menopause abnormal uterine bleeding and, 301 amenorrhea with, 259 Hypogonadism hypergonadotropic, 165. See also Premature ovarian failure; Turner’s syndrome hypogonadotropic, 165, 301, 316. See also Amenorrhea, primary Hypomenorrhea, 297 Hyponatremia, hysteroscopy and, 627, 679–680, 679t Hypophyseal artery, 4 Hypophysitis, lymphocytic, 316–317 Hypopituitarism, 316–317. See also Adenoma, pituitary Hypothalamic-pituitary-ovarian axis, 1–7, 1t, 2t, 5f, 6t, 27f, 28–33. See also Follicle-stimulating hormone (FSH); Gonadotropin-releasing hormone (GnRH); Luteinizing hormone (LH); Pituitary gland in puberty, 157–158, 157f
815
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Hypothalamic pulse generator, 28–29 Hypothalamus, 1–4, 1t, 2f, 28–30, 311, 311t. See also Gonadotropin-releasing hormone (GnRH); Pituitary gland estrogen receptors of, 3 neurotransmitter effects on, 3, 3t nuclei of, 1, 2f Hypotheses, tests of, 141–142 Hypothyroidism, 325–327 antithyroid antibodies in, 326 causes of, 325, 325t clinical features of, 325–326 fertility and, 324–325 fetal, 330 hyperprolactinemia and, 257 in infertility evaluation, 513–514 laboratory tests in, 326 lipid disorders and, 326 menstrual cycle and, 3t neonatal, 329 ovulatory dysfunction and, 278, 280t, 301, 519 postpartum, 330 pregnancy and, 329 radioactive iodide uptake test in, 326 recurrent pregnancy loss and, 611 subclinical, 325 treatment of, 326–327 ultrasonography in, 326 Hypovolemia, in ovarian hyperstimulation syndrome, 598 Hysterectomy in abnormal uterine bleeding, 308 in endometriosis, 740 laparoscopic, 663–664, 688 menopause and, 354 in premenstrual syndrome, 342 sterilization and, 426 supracervical, 664 vaginal, 664, 688 Hysterosalpingography, 429–437, 430f accuracy of, 430–431 analgesia for, 432–433 cannulas for, 433 cervical stenosis and, 433 vs. Chlamydia antibody testing, 435–436 contraindications to, 431–432 contrast media for, 433 vs. diagnostic laparoscopy, 436 endometrial carcinoma and, 432 vs. falloposcopy, 436–437 fertility after, 435 granuloma formation and, 435 historical perspective on, 430 vs. hysteroscopy, 436 indications for, 430–431 infection and, 431–432, 434 in infertility evaluation, 517–518 in intrauterine adhesions, 430f, 643 iodine allergy and, 432 vs. magnetic resonance imaging, 436 menstruation and, 432 oil embolism and, 435, 435f pregnancy and, 432 radiation with, 434–435 vs. radionuclide scanning, 436 in recurrent pregnancy loss, 618 risks of, 434–435 432f vs. salpingoscopy, 436–437 in secondary amenorrhea, 249
Hysterosalpingography (Continued) sensitivity of, 430–431 in septate uterus, 178, 650, 651 vs. sonohysterography, 436 vs. sonohysterosalpingography, 436 specificity of, 430–431 technical aspects of, 430f, 432–433 timing of, 432 vs. transvaginal hydrolaparoscopy, 436 in tubal abnormalities, 430–431, 431f, 432f, 434, 697–698 vs. ultrasonography, 436 in unilateral proximal tubal occlusion, 434 in uterine cavity abnormalities, 430, 430f, 431f vasovagal reaction with, 434 Hysteroscope, 626 Hysteroscopic transcervical cannulation, in proximal tubal occlusion, 699–700, 700f Hysteroscopy, 304, 625–638 in adolescents, 205 allergic reactions with, 627 analgesia for, 627 anesthesia for, 627 carbon dioxide for, 626, 678–679 cervical laceration with, 678 complications of, 678–680, 678t, 679t, 680t dextran for, 626–627, 679 diagnostic, 627–628 indications for, 625 in intrauterine adhesions, 644 in septate uterus, 650, 651 disappearing phenomena with, 628 disseminated intravascular coagulopathy with, 626 distension media for, 626–627 complications of, 678–680, 679t in endometrial polyps, 628 equipment for, 626 false-negative views on, 628 fluid overload with, 626, 679 gas embolism with, 626 glycine for, 627, 679 historical perspective on, 625 hyponatremia with, 627, 679–680, 679t vs. hysterosalpingography, 436 indications for, 625–626 infection with, 680 low-viscosity fluid for, 627 mannitol for, 627, 679 office, 627–628 operative indications for, 626. See also Endometrial ablation in intrauterine adhesions, 644–647 in leiomyoma, 628–633. See also Myomectomy, hysteroscopic in septate uterus, 651, 652–653, 652f, 654 power sources for, 627 in recurrent pregnancy loss, 618 Ringer’s solution for, 627 sodium chloride fluid for, 627 sorbitol for, 627, 679 for sterilization, 425, 426f, 626 uterine bleeding with, 678 uterine perforation with, 646, 654, 678
I Ibandronate, in osteoporosis, 379 Icodextrin, 787
Iliac vessels, 119–121, 120f on ultrasonography, 453–454 Iliacus, 119 Iliohypogastric nerve, 116–117 laparoscopy-related injury to, 668f, 669 Ilioinguinal nerve, 116–117 laparoscopy-related injury to, 668f, 669 Immune response acquired, 613 innate, 613 maternal, 614 Immune system, 612–613 disorders of, recurrent pregnancy loss and, 613–615 Immunochemiluminometric assay, 32 Immunoglobulin, intravenous, recurrent pregnancy loss and, 620–621 Immunoradiometric assay, 32 Immunosuppression, recurrent pregnancy loss and, 614, 615 Immunotherapy, in recurrent pregnancy loss, 620–621 Imperforate hymen, 179, 180f, 206, 206f, 237 Implanon, 400 Implantation, 107–111 angiogenesis in, 111 decidualization and, 110 embryonic contribution to, 107–108 HOX genes in, 109–110 human chorionic gonadotropin in, 109 integrins in, 108 interleukins in, 109 invasive phase of, 110–111 mucins in, 108 natural killer cells in, 111 prostaglandins in, 109 trophinin in, 108 vascular endothelial growth factor in, 109 vasculogenesis in, 111 window of, 108 In vitro fertilization, 66, 567, 589–590 age and, 569, 569f antimüllerian hormone in, 570 antral follicle count in, 570 assisted hatching in, 592 basal follicle-stimulating hormone in, 569–570, 571 blastocyst transfer in, 592 in cancer patients, 490–491 clomiphene citrate challenge test in, 570–571 congenital anomalies and, 603 conventional insemination in, 589–590 in DES-exposed woman, 569 donor privacy in, 150 embryo assessment in, 591–592 embryo transfer for, 111, 574–576, 575f, 576t, 603 endometrial polyps and, 569 endometrial receptivity in, 111 endometriosis and, 738 estradiol levels in, 570 ethical issues in, 150 failure of, 591 fertilization checks in, 591 human chorionic gonadotropin in, 576 hydrosalpinges and, 569, 703–705 inhibin B levels in, 570 intracytoplasmatic sperm injection in, 590, 591f luteal phase management for, 576, 600
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In vitro fertilization (Continued) multiple pregnancy with, 601–603, 601f, 602t natural-cycle, 572 oocyte donation for, 577 oocyte in vitro maturation in, 572 oocyte retrieval for, 574, 574f ovarian stimulation for, 571–574 in cancer patients, 490–491 clomiphene citrate in, 571 endometrial monitoring of, 573 estradiol monitoring of, 573–574 gonadotropin-releasing hormone agonists in, 571–572 gonadotropin-releasing hormone antagonists in, 572 gonadotropins in, 571 human chorionic gonadotropin in, 571 leuprolide acetate in, 571–572 monitoring of, 572–574 ovarian hyperstimulation syndrome with, 597–601. See also Ovarian hyperstimulation syndrome ultrasonography in, 448, 449f, 573 ovary evaluation for, 569–571, 569f patient selection for, 569–571, 569f in polycystic ovary syndrome, 568–569 preimplantation genetic diagnosis in, 99, 592–593 progesterone in, 576 results of, 576–577, 603 sonohysterography before, 448 ultrasonography in, 448, 570 uterus evaluation for, 569 zona pellucida defects in, 592 Incidentaloma, 322–323, 322t Independent variable, 137 Infant mortality, assisted reproductive technology and, 602 Infarction, pituitary, 317 Infection abnormal uterine bleeding and, 298 artificial insemination and, 545 fallopian tube, 130–131, 131f hysterosalpingography and, 431–432, 434 hysteroscopy and, 680 intrauterine device placement and, 411, 412, 412t recurrent pregnancy loss and, 615, 619, 621 transvaginal follicle aspiration and, 603–604 Infectious mononucleosis, vulvar ulcers and, 197 Infertility, 507–522, 525–537 artificial insemination for, 539–546. See also Artificial insemination in cancer patient, 485–505. See also Cancer, fertility preservation in evaluation of, in females, 509–521, 510t, 516t abdominal examination in, 514 acanthosis nigricans in, 514 adnexal abnormalities in, 516, 516t androgens in, 520 basal body temperature chart in, 518, 518f blood typing in, 516 body piercing in, 514–515 breast examination in, 514 cervical abnormalities in, 515 cervical factor in, 519–520 clitoromegaly in, 515 clomiphene citrate challenge test in, 520 coital frequency in, 512, 512f demographic history in, 510 dyspareunia in, 512–513
Infertility (Continued) evaluation of, in females (Continued) endometrial biopsy in, 519 family history in, 511, 511t follicle-stimulating hormone assay in, 32, 32t galactorrhea in, 514 genetic disease in, 511, 511t, 517 gynecologic examination in, 515–516 gynecologic history in, 510–511 headache in, 513 herbal preparations in, 512 hirsutism in, 514 hysterosalpingography in, 430–431, 435, 517–518. See also Hysterosalpingography IUD use in, 511 laparoscopy in, 518 luteinizing hormone assay in, 32, 32t medical history in, 511 menstrual history in, 510 nutritional history in, 512 obstetric history in, 511 ovarian reserve in, 520–521 ovulation evaluation in, 518–519, 518f Pap smear in, 511, 516 patient history in, 510–513, 511t, 512f physical examination in, 513–516 postcoital test in, 520 preconception screening in, 516–517, 516t prolactin in, 519 review of systems in, 513 rubella titer in, 516 serum progesterone in, 518–519 sexual dysfunction in, 512 sexual history in, 512–513, 512f sexual orientation in, 513 sexually transmitted diseases in, 517 skin examination in, 514–515 social history in, 512 sonohysterography in, 517 sonohysterosalpingography in, 517 surgical history in, 511 tattooing in, 514 thyroid disease in, 513–514 thyrotropin in, 519 ultrasonography in, 517 urinary luteinizing hormone in, 519 uterine abnormalities in, 515, 516t varicella screening in, 516–517 visual changes in, 513 weight in, 513 evaluation of, in males, 527–530, 528f antisperm antibody testing in, 531, 540, 568 endocrine testing in, 531–532 family history in, 529 female partner history in, 529 fertility history in, 529 genetic testing in, 525, 532, 533f–534f genitalia examination in, 529–530, 530f, 530t karyotyping in, 532, 533f–534f medical history in, 528, 529 patient history in, 527–529 physical examination in, 529–530 semen analysis in, 517, 530–531, 531t seminal vesical aspiration in, 536 sexual history in, 529 social history in, 529 surgical history in, 528–529 testis biopsy in, 535–536, 535f, 793 ultrasonography in, 532, 534, 534f, 535f, 793
Infertility (Continued) evaluation of, in males (Continued) vasogram in, 534, 534f Y-chromosome microdeletion testing in, 532 female, 507–522 assisted reproductive technology in, 567–578. See also Assisted reproductive technology; In vitro fertilization bacterial vaginosis and, 501 causes of, 508–509, 509t cervical stenosis and, 503 cervicitis and, 497–499, 500, 502–503 chancroid and, 501 Chlamydia trachomatis and, 498–499, 498t, 504 definition of, 507, 507t emotional aspects of, 521 endometriosis and, 568, 736–737, 738 endometritis and, 503 gonorrhea and, 497–498, 498f hepatitis and, 501 herpes simplex virus infection and, 500 HIV infection and, 504–505 human papillomavirus infection and, 500 hyperprolactinemia and, 259 hypothalamic amenorrhea and, 242 intrauterine adhesions and, 503 leiomyoma and, 684 mycoplasma infection and, 500 polycystic ovary syndrome and, 218. See also Polycystic ovary syndrome sexually transmitted infections and, 497–505, 497t, 498t stress and, 509 syphilis and, 499 treatment of, 521. See also Assisted reproductive technology; In vitro fertilization trichomonas and, 499–500 tubal disorders and, 503, 510, 568 tuberculosis and, 501, 510 ureaplasmas and, 500 weight and, 509 male, 525–537 anabolic steroids and, 527 antisperm antibodies and, 531, 540, 568 cancer therapy and, 492–493, 527 clomiphene citrate in, 536 congenital vas deferens absence and, 532 cystic fibrosis and, 526–527 diagnosis of, 793–794 ejaculation induction in, 536 ejaculatory dysfunction and, 527, 540–541, 585, 797 epididymal obstruction and, 797, 798 genetics of, 98 Klinefelter’s syndrome and, 526, 532 L-carnitine in, 536 medical disease associated with, 525 medical therapy in, 536 medications and, 527 pathophysiology of, 525–527, 526t retrograde ejaculation and, 585 sympathomimetics in, 536 treatment of, 525, 535–536, 794–801. See also Artificial insemination varicocele and, 526, 530, 530f, 530t, 798–799 vasography in, 793–794 Y-chromosome microdeletion and, 527, 532
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Infertility (Continued) unexplained artificial insemination in, 541 in vitro fertilization in, 66, 568 Inflammatory bowel disease, in adolescent, 212 Informed consent for artificial insemination, 546 for sterilization, 417–418, 417t Infundibulopelvic ligament, 124 Inguinal canal, 115, 116f Inguinal ring, 115–116, 116f Inheritance. See also Chromosome(s) autosomal dominant, 91, 91f autosomal recessive, 91–92, 91f mitochondrial, 93, 93f multifactorial, 92–93 X-linked, 92, 92f Inhibin, 1t, 6–7, 25–26, 25f, 25t, 27f, 27t extragonadal, 26 function of, 43 in ovarian tumors, 26 Inhibin A, 7, 25–26, 25f, 25t assay of, 25–26 in menstrual cycle, 10f, 11, 12 Inhibin B, 7, 25–26, 25f, 25t assay of, 25–26 after chemotherapy, 486 in in vitro fertilization, 570 in menstrual cycle, 10f, 11, 12 Sertoli cell production of, 26 Inhibin receptor, 43 Insulin granulosa cell effect of, 222 in polycystic ovary syndrome, 220–221, 222 Insulin growth factor binding protein-1, in decidualization, 110 Insulin-like growth factor–I (IGF-I), 27, 27t in acromegaly, 314 gonadotropin-releasing hormone effects of, 220 Insulin-like growth factor–I (IGF-I) receptor, 40f, 42, 220 Insulin-like growth factor–II (IGF-II), 27, 27t, 220 Insulin-like growth factor binding protein–related protein, in implantation, 109 Insulin resistance hirsutism and, 265–266 oral contraceptives and, 392 in polycystic ovary syndrome, 222, 224–225, 224f, 283–284, 301 recurrent pregnancy loss and, 611, 620 Insulin-sensitizing agents, ovulation induction with, 555–556 Insulin tolerance test, in adrenal insufficiency, 318 Integrins, 53 in endometriosis, 736 in implantation, 108 Interceed, in adhesion prevention, 787 Intercellular adhesion molecule-1, in endometriosis, 734 Interleukin-1, 27t, 28 in endometriosis, 734 in implantation, 109 Interleukin-1β, in decidualization, 110 Interleukin-6, 27t, 28 in endometriosis, 734 in implantation, 109 Interleukin-8, in endometriosis, 734 Interleukin-11, in implantation, 109
Intestine in acromegaly, 314 adhesion-related obstruction of, 781–782, 781f cancer of, 391 endometriosis of, 735–736, 741, 741f laparoscopy-related injury to, 674–675 thermal injury to, 674 Intracytoplasmatic sperm injection, 590, 591f Intraperitoneal fluid, on vaginal ultrasonography, 451 Intrauterine adhesions, 235t, 247, 641–647 classification of, 642–643, 642t clinical manifestations of, 643 diagnosis of, 643–644 etiology of, 641 female infertility and, 503 fluoroscopic-guided lysis of, 645 hysterosalpingography in, 430f, 643 after hysteroscopic myomectomy, 631 hysteroscopy of diagnostic, 644 surgical, 644–647 March classification of, 642, 642t mechanical saline infusion disruption of, 645 pathophysiology of, 642 pressure lavage under ultrasound guidance in, 450 prevalence of, 641 prevention of, 645–646 recurrent pregnancy loss and, 612, 620 risk factors for, 641 saline infusion sonohysterography of, 643 surgical treatment of, 644–647 complications of, 646 hormonal therapy after, 646 intrauterine device after, 645–646 results of, 646–647 tuberculosis and, 647 ultrasonography of, 454, 643–644 Intrauterine device (IUD), 405–415 abnormal uterine bleeding and, 409 Actinomyces and, 411 amenorrhea with, 408, 408t complications of, 414–415, 414f contraindications to, 412, 412t copper-containing, 406, 406f, 407, 409 costs of, 408 discontinuation rates for, 407–408, 408t dysmenorrhea and, 409, 410 ectopic pregnancy and, 410–411 efficacy of, 407 for emergency contraception, 407 estrogen replacement therapy and, 409 expulsion of, 414 fertility and, 409 foreign body effect of, 407 historical perspective on, 405–406 HIV infection and, 412 in infertility evaluation, 511 insertion of, 413 in intrauterine adhesion recurrence prevention, 645–646 irregular bleeding with, 410 leiomyoma and, 410 levonorgestrel-containing, 406–407, 406f, 409–410, 412 lost, 444 mechanisms of action of, 407 menorrhagia and, 410 menstrual abnormalities with, 408, 408t missing strings of, 414, 414f
Intrauterine device (IUD) (Continued) noncontraceptive benefits of, 409–410 patient selection for, 411–412 pelvic inflammatory disease and, 411 postpartum insertion of, 413 pregnancy and, 408, 408t, 410–411 preplacement examination for, 412–413 progestin-impregnated, 406 removal of, 413–414 pregnancy and, 410 side effects of, 410 tamoxifen and, 409–410 ultrasonography of, 444 uterine perforation and, 414 Intravasation, hysterosalpingography and, 435, 435f Intron, 85–86, 85f Iodine-131 uptake tests, in thyroid disease, 326 Iodine allergy, hysterosalpingography and, 432 Ionizing radiation, recurrent pregnancy loss and, 617 Irritable bowel syndrome in adolescent, 212 menstrual cycle and, 345–346 Irving technique, of tubal ligation, 418, 420f Isolated gonadotrophin deficiency, 237–238 IUD. See Intrauterine device (IUD)
J Jones metroplasty, 653 Justice, 147–148
K KAL1 gene, 237–238 Kallmann syndrome, 3t, 166, 237–238, 280t Kaplan-Meier curve, 143 Karyotype, 86 in delayed puberty, 166 Kaufman-McKusick syndrome, 97–98 Kawasaki syndrome, 197 Kidney disease galactorrhea and, 257 in Mayer-Rokitansky-Küster-Hauser syndrome, 760 Kinetochores, 62 c-Kit, 53 Klinefelter’s syndrome, 88t, 98, 526, 532 Klippel-Feil syndrome, 176 Kroener technique, of sterilization, 419, 422f
L Labial adhesions, 197 Lactation, 254–256 anovulation and, 254–256 bone loss during, 373 involution after, 256 mammary gland differentiation for, 254 oral contraceptives and, 395, 396 Lactogenesis, 254 Lactose malabsorption, in adolescent, 212 Lactotrophs, 6t Laminaria, in hysteroscopic myomectomy, 630 Langerhans’ cell histiocytosis, 198
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Laparoscopy, 659–665 in cancer, 664 carbon dioxide gas for, 669–670 closed, 659–660, 660f complications of, 667–678 bladder, 675–676, 675t carbon dioxide, 669–670 electrosurgical, 676–678 embolic, 670 femoral nerve, 667–668, 668f gastric, 673–674 gastrointestinal, 673–674, 675f genitofemoral nerve, 668f, 669 hernia, 674–675, 675f iliohypogastric nerve, 668f, 669 ilioinguinal nerve, 668f, 669 intestinal, 674–675, 675f nerve, 667–669, 668f obturator nerve, 668, 668f sciatic nerve, 669 thermal, 674 ureteral, 676 urinary tract, 675–676, 675t vascular, 670–673, 672f diagnostic, 662, 662f vs. hysterosalpingography, 436 in infertility evaluation, 518 direct trocar insertion for, 660 in ectopic pregnancy, 663 electrosurgery in, 676–678, 676t. See also Electrosurgery, laparoscopic in endometriosis, 211–212, 663 historical perspective on, 659 in hysterectomy, 663–664 large vessel occlusion for, 662 laser, 678 left upper quadrant technique for, 660, 661f in myomectomy, 663 in oophorectomy, 663 open, 660 in ovarian cystectomy, 663. See also Cystectomy, laparoscopic in pelvic adhesions, 663 ports for, 659–660, 660f, 661, 661f bladder injury with, 675–676, 675t herniation with, 674–675, 675f removal of, 661 site closure for, 661 power instruments for, 661–662 primary trocar placement for, 659–660, 660f proficiency in, 664 risks of, 664 secondary port placement for, 661, 661f trocar placement for, 659–660, 660f tubal for ectopic pregnancy, 663 for reconstruction, 663 for sterilization, 419, 421, 423–424, 423f, 424f, 662 in uterine nerve ablation, 663 Veress needle insertion for, 659–660, 660f, 671 complications of, 670–671, 673 Large intestine in acromegaly, 314 cancer of, 391 endometriosis of, 735–736, 741, 741f inflammatory disease of, 212 laparoscopy-related injury to, 674–675 thermal injury to, 674
Larmor equation, 461 Laser assisted hatching, 592 Laser therapy in hirsutism, 227, 270 laparoscopic, 678 Latin square design, 138 Lavage, pressure, under ultrasound guidance, 450 Lead exposure, recurrent pregnancy loss and, 617 Leiomyoma, 683–693 bleeding and, 298, 683 body mass index and, 684 cigarette smoking and, 684 classification of, 628–629, 628f, 629f, 629t, 683, 684f clinical manifestations of, 683–684 endocrinology of, 685–686, 685f endometriosis and, 730 epidemiology of, 684 estrogen in, 685–686, 685f familial predisposition to, 684 genetics of, 684–685 histology of, 129–130, 129f, 129t, 130f hysterosalpingography in, 686 hysteroscopy for, 628–633. See also Myomectomy, hysteroscopic infertility and, 684 levonorgestrel-containing IUD in, 410 magnetic resonance imaging in, 472, 475f, 686–687 multiple, 683, 684f pathology of, 129–130, 129f, 129t, 130f, 685 pathophysiology of, 684–686, 685f pelvic pain with, 683 pregnancy and, 683, 684, 686 prevalence of, 683 progesterone in, 685–686, 685f recurrent pregnancy loss and, 612, 620 size of, 683, 684f sonohysterography in, 443, 443f staging of, 629–630 treatment of, 687–690 cryomyolysis in, 692 gonadotropin-releasing hormone agonists in, 687 high-intensity MRI-guided focused ultrasound surgery in, 691–692, 692f hysterectomy in, 688 medical, 687–688 myomectomy in, 628–633, 688–690, 689f, 690f. See also Myomectomy, hysteroscopic selective estrogen receptor modulators in, 687–688 selective progesterone receptor modulators in, 688, 688f surgical, 123, 688–690, 689f uterine artery embolization in, 690–691, 690f, 691f uterine artery ligation in, 692 type 0 (class 1), 628, 628f, 629f, 629t type I (class 2), 628, 629, 629f, 629t type II (class 3), 628, 629, 629t, 630, 630f ultrasonography in, 443, 443f, 454, 686 Leiomyosarcoma, 130, 130f, 131t Leptin, 278 in eating disorders, 242 in endometriosis, 734 in implantation, 111 puberty and, 158
Lesbians infertility evaluation for, 513 parentage and, 149–150 Letrozole in in vitro fertilization, 490–491 ovulation induction for, 557–559, 557t Leucine-rich repeat-containing G protein-coupled receptor 8, 60–61 Leucovorin, with methotrexate, 719 Leukemia inhibitory factor, in implantation, 109 Leukotrienes, in dysmenorrhea, 202, 202f Leuprolide, 4t in endometriosis, 739 in fertility preservation, 487–488, 488t in hirsutism, 270 in in vitro fertilization, 571–572 in precocious puberty, 162–163 Levator ani, 121–122, 122f Levator plate, 122 Levonorgestrel intrauterine system, 406–407, 406f. See also Intrauterine device (IUD) in abnormal uterine bleeding, 307 in endometriosis, 739 Levonorgestrel-only regimen, for emergency contraception, 396–397 Levothyroxine in hypothyroidism, 326 in pregnancy, 329 Leydig cell, 73 Leydig cell hypoplasia, male pseudohermaphroditism and, 183–184 LH. See Luteinizing hormone (LH) Lichen sclerosis et atrophicus, 197 Liddle’s syndrome, 321 Ligand-dependent transcription factors. See Receptors, steroid hormone Likelihood ratio, 750 Lipids, 17–18, 18f oral contraceptive effects on, 392 Lipoma, perineal, congenital, 198 Lipoproteins, oral contraceptive effects on, 392 Liquid chromatography–mass spectrometry, 23 Liver estradiol metabolism in, 8–9, 21–22 hemangioma of, 662, 662f progesterone metabolism in, 9, 22 testosterone metabolism in, 22 Logistic regression equation, 143, 143t Low molecular weight heparin in antiphospholipid antibody syndrome, 620 in thrombophilia, 621 Luteal phase defect definition of, 280 ovulatory dysfunction in, 278 recurrent pregnancy loss and, 611, 620 Lutein, 11 Luteinization, 11 Luteinized unruptured follicle syndrome, 278, 519 Luteinizing hormone (LH), 1t, 6, 311t. See also Follicle-stimulating hormone (FSH) adenoma secretion of, 316 assay of, 31–32, 32t biosynthesis of, 30–31 deficiency of, 316 in delayed puberty, 166 gene mutations in, 31 in hirsutism, 269 in in vitro fertilization, 571 in male infertility evaluation, 532
819
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Luteinizing hormone (LH) (Continued) in ovulation, 550, 550f in ovulatory dysfunction, 281–282 physiologic role of, 10, 10f, 11, 12, 30 in polycystic ovary syndrome, 203, 218–219, 219f, 222 in precocious puberty, 161 in premature ovarian failure, 291 progesterone effects on, 9 in puberty, 157, 157f, 158 structure of, 30–31, 30f urinary in artificial insemination, 542 in clomiphene citrate–induced ovulation, 552 in ovulation evaluation, 519 Luteinizing hormone (LH) receptors, 6, 38–41 abnormalities of, 238 gene mutations in, 40–41, 59 mechanism of action of, 38–39, 40f structure of, 38, 39f Luteolysis, 12 Luteoma, pregnancy-related, 132, 133f Lymphangiomyomatosis, pulmonary leiomyomatosis and, 684–685 Lymphocytes pregnancy effects on, 328 T, 613 in endometriosis, 733 Lymphocytic hypophysitis, 316–317 Lymphogranuloma venereum, 499
M
820
Macrophage, in endometriosis, 733–734 Macrophage migration inhibitory factor, in endometriosis, 734 Macroprolactin, 33 Madlener technique, of tubal ligation, 418, 419f Magnetic resonance imaging (MRI), 461–483 in adenomyosis, 299, 467, 471f, 472, 472f–474f in arcuate uterus, 178, 464, 464f in bicornuate uterus, 177–178, 464–467, 467f, 768 in cervical agenesis, 766, 766f in cervical anomalies, 472, 476f vs. computed tomography, 462 in congenital anomalies, 464–467, 464f–470f in dermoid cyst, 472, 477f in endometrioma, 478, 479f in endometriosis, 478, 478f, 481f vs. hysterosalpingography, 436 in leiomyoma, 472, 475f in Mayer-Rokitansky-Küster-Hauser syndrome, 760 in nabothian cyst, 462, 463f, 472, 476f normal anatomy on, 462, 462f–463f in ovarian cyst, 472, 477f of ovary, 472, 477f–481f, 478 in peritoneal inclusion cyst, 478, 480f–481f of pituitary gland, 5f post-cesarean defect on, 472, 476f principles of, 461 in recurrent pregnancy loss, 618–619 in septate uterus, 178, 464–467, 465f, 466f, 651, 768 in unicornuate uterus, 177, 464, 464f of urethra, 481–482, 483f in urethral diverticulum, 482, 483f
Magnetic resonance imaging (MRI) (Continued) in uterine agenesis, 464, 464f in uterus didelphys, 465, 468f–470f in vaginal agenesis, 176 Magnetic resonance imaging (MRI)–guided high-intensity focused ultrasound surgery, in leiomyoma, 691–692, 692f Major histocompatibility complex, 613 Major histocompatibility locus, recurrent pregnancy loss and, 614 Makler counting chamber, for sperm concentration, 582–583 Malnutrition, type 2 diabetes and, 222 Mannitol, for hysteroscopy, 627, 679 Marfan syndrome, 91 Margin of error, 141 Mastalgia, premenstrual, 342 Mastocytosis, vasomotor symptoms in, 355 Maternal age artificial insemination and, 545 chromosome abnormalities and, 99 motherhood and, 148–149 recurrent pregnancy loss and, 609 Maternal effect genes, 63–64 Matrix metalloproteinases in endometriosis, 733 in implantation, 110–111 Maturation promotion factor, 61 Mayer-Rokitansky-Küster-Hauser syndrome, 98, 174, 175f, 176, 236–237, 759–760 amenorrhea in, 165, 207 clinical presentation of, 759–760 diagnosis of, 760 endometriosis in, 765 etiology of, 760 imaging in, 236–237, 760 magnetic resonance imaging in, 760 neovagina creation in, 760–765 adhesion barrier lining in, 764 amnion lining in, 764 bowel vaginoplasty in, 764–765 Davydov procedure in, 764 McIndoe procedure in, 762–764, 762f, 763f muscle flap in, 764 peritoneal graft in, 764 pudenal-thigh flap in, 764 skin flap in, 764 vaginal dilation for, 760–761, 760f, 761f vaginoplasty techniques in, 761–765, 762f, 762t, 763f Vecchietti procedure for, 761 renal abnormalities in, 760 rudimentary uterine bulbs in, 765, 765f ultrasonography in, 760 McCune-Albright syndrome, 164 McIndoe procedure, in neovagina creation, 762–764, 762f, 763f Mean(s), 139 comparison of, 142 population, 137 sample, 137 Meckel-Gruber syndrome, 186 Median eminence, 311 Medical history in female infertility evaluation, 511 in male infertility evaluation, 528 Medroxyprogesterone acetate in abnormal uterine bleeding, 306, 307 amenorrhea and, 243
Medroxyprogesterone acetate (Continued) in catamenial epilepsy, 344 depot, 243, 373, 399–400 in endometriosis, 739 in menopause, 364 osteoporosis and, 373 Mefenamic acid, in premenstrual syndrome, 341 Meig syndrome, 750 Melanoma, 198 Menarche, 159 Mendelian genetics, 90–92 autosomal dominant, 91, 91f autosomal recessive, 91–92, 91f X-linked, 92, 92f Menometrorrhagia, 297 Menopause, 20, 288, 301, 353–367 acupuncture in, 367 age of, 353, 354 alcohol intake and, 366 androgens in, 364 calcium in, 365 cardiovascular disease and, 358 clonidine in, 364 complementary and alternative therapy in, 366–367 demographics of, 353 dietary therapies in, 365–366 early onset of, 353–354, 354t exercise in, 365–366 gabapentin in, 364–365 hormone therapy in, 358–362, 359t, 360t, 361t hot flashes in, 355–357. See also Hot flashes medical treatment of, 358–365, 359t, 360t, 361t, 362t migraine and, 357 osteoporosis and, 357–358. See also Osteoporosis physiology of, 353–354 progestins in, 364 selective estrogen receptor modulators in, 362–363 selective serotonin reuptake inhibitors in, 364, 364t stages of, 354–355, 354f tamoxifen in, 362–363 urinary tract infection and, 357 urogenital changes with, 357 vaginal changes with, 357 veralipride in, 365 vitamin D in, 365 Menorrhagia. See also Abnormal uterine bleeding in adolescent, 203, 204–205, 303 definition of, 297, 303 levonorgestrel-containing IUD in, 410 in Von Willebrand’s disease, 301–302 Menstrual calendar for abnormal uterine bleeding evaluation, 302, 302f for premenstrual syndrome evaluation, 336–337, 338f, 339f Menstrual cycle, 10–12, 10f. See also Menstruation; Premenstrual syndrome abnormal cessation of. See Amenorrhea activin in, 26 appendicitis and, 346 arthritis and, 346 asthma and, 345 chemotherapy effects on, 485–486, 486t diabetes mellitus and, 346 disease exacerbations and, 343–347 endometrial histology in, 125–126, 125f, 125t, 126f endorphin levels during, 6
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Menstrual cycle (Continued) epilepsy and, 344–345 estradiol in, 8, 10–11, 10f, 20, 21, 21f follicle-stimulating hormone in, 6, 10, 10f, 11, 12 follicular phase of, 10–12, 10f gonadotropin-releasing hormone in, 10, 11, 12 inhibin A in, 10f, 11, 12 inhibin B in, 10f, 11, 12 irritable bowel syndrome and, 345–346 length of, 10 luteal-follicular transition of, 12 luteal phase of, 10f, 12 luteinizing hormone in, 6, 10, 10f, 11, 12 migraine and, 343–344 neurotransmitter effects on, 3, 3t onset of, 159 in ovulatory dysfunction, 280–281, 280t ovulatory phase of, 10f, 11 pheromones and, 3t pneumothorax and, 346 progesterone in, 10f, 11 progesterone receptors in, 37 serotonin levels and, 340, 340f steroidogenesis during, 7–10, 7f, 7t, 8f, 8t Menstrual history, in infertility evaluation, 510 Menstruation. See also Menstrual cycle; Premenstrual syndrome abnormal. See Abnormal uterine bleeding abnormal cessation of. See Amenorrhea hysterosalpingography and, 432 intrauterine devices and, 408, 408t, 409, 410 normal, 297, 300 after sterilization, 426 Mesentery, 116 Mesonephric (Wolffian) ducts, embryology of, 171–172, 172f Metabolic syndrome, in polycystic ovary syndrome, 222–223 Metanephrines, in pheochromocytoma, 322 Metaphase I, of oogenesis, 51, 52f Metaphase II, of oogenesis, 51, 53f Metformin in hirsutism, 270–271 ovulation induction with, 283–284, 555–556 in polycystic ovary syndrome, 203, 226–227, 226f, 556 in recurrent pregnancy loss, 620 Methimazole, in hyperthyroidism, 327–328 Methotrexate, ectopic pregnancy treatment with, 718–721, 719t, 720t cervical pregnancy and, 723 contraindications to, 719, 719t cornual pregnancy and, 722 efficacy of, 721 fertility after, 724 indications for, 719 injection protocol for, 721 leucovorin with, 719 mechanism of action of, 719 multidose protocol for, 720, 720t pain with, 720–721 pretreatment evaluation in, 719 protocols for, 719–720, 720t side effects of, 720 single-dose protocol for, 720, 720t vs. surgery, 721 Methoxamine, in male infertility, 536 Methylxanthines, premenstrual syndrome and, 340 Metronidazole, in abnormal uterine bleeding, 306
Metroplasty abdominal, 653–654 hysteroscopic, 651, 652–653, 652f, 654 Jones, 653 Strassman, 768 Tompkins, 653–654 Metrorrhagia, 297 Metyrapone test, in adrenal insufficiency, 318 Microdeletion syndromes, 90, 90f Microhemagglutination assay for Treponema pallidum (MHA-TP) test, 499 Microtubule organizing center, of oocyte, 64 Microwave Endometrial Ablation System, 636t, 637–638 Mifepristone, 37 in Cushing’s disease, 315 Migraine menstrual, 343–344 postmenopausal, 357 Miller-Dieker syndrome, 90t Mineralocorticoid deficiency, 319 Mirena IUD, 406–407, 406f. See also Intrauterine device (IUD) Miscarriage, 609. See also Abortion, spontaneous; Recurrent pregnancy loss Misoprostol, in hysteroscopic myomectomy, 631 Missense mutation, 86 Mitotane, in Cushing’s disease, 315 Mixed gonadal dysgenesis, 185–186 delayed puberty in, 165, 166 MKKS gene, 98 Mlh1, 55 Mlh5, 55 Mobiluncus infection, abnormal uterine bleeding and, 306 Mode, 139 Molimina, 335. See also Premenstrual syndrome Monocyte chemoattractant protein-1, in endometriosis, 733–734 Monosomy, partial, 88 Mood, depot medroxyprogesterone acetate and, 400 Mosaicism, 87, 95 Msh4, 54–55 Msh5, 54–55 MTHFR gene, recurrent pregnancy loss and, 615–616, 615t, 621 MUC proteins, 108 Mucins, in implantation, 108 Müllerian agenesis. See Mayer-RokitanskyKüster-Hauser syndrome Müllerian ducts. See Paramesonephric (Müllerian) ducts Müllerian inhibiting substance, 58, 96, 96f, 98 Müllerian tubercle, 173 Multicollinearity, 142–143 Multiple endocrine neoplasia syndrome, 331 Multiple regression analysis, 142–143 Muscle flap, in neovagina creation, 764 Mutation, 86. See also Genetic disorders MutL, 54–55 MutS, 54–55 Mycobacterium tuberculosis infection, infertility and, 501, 510 Mycoplasma hominis infection, infertility and, 500 Myocardial infarction oral contraceptives and, 393–394 postmenopausal, 358 Myoma. See Leiomyoma
Myomectomy hysteroscopic, 628–633 bipolar technology for, 633 carboprost for, 632–633 cervical dilation for, 631 cervical preparation for, 630–631 classification systems for, 628–630, 629f, 629t, 630f complications of, 631t discharge after, 633 fertility preservation and, 632 laminaria for, 630 loop resection technique for, 632 management after, 633 misoprostol for, 631 negative view with, 632 paracervical block for, 631 patient selection for, 630 prophylactic antibiotics for, 631 technique of, 631–632 ultrasonography with, 633 uterine distension for, 631–632 vaporization electrode for, 632 vasopressin for, 631 laparoscopic, 663, 689–690, 690f surgical, 123, 688–689, 689f Myometrium, 123 contractions of, 453 Myotonic dystrophy, 95, 289 Myxedema coma, 326. See also Hypothyroidism
N Nabothian cyst, 462, 463f, 472, 476f Naferelin, 4t in endometriosis, 739 in hirsutism, 270 in precocious puberty, 162–163 Natural killer cells in implantation, 111 recurrent pregnancy loss and, 614 Nausea, oral contraceptives and, 394 Neisseria gonorrhoeae infection infertility and, 497–498, 498f, 498t sexual abuse and, 196 Neovagina, 760–765 adhesion barrier lining in, 764 amnion lining in, 764 bowel vaginoplasty in, 764–765 Davydov procedure in, 764 McIndoe procedure in, 762–764, 762f, 763f muscle flap in, 764 peritoneal graft in, 764 pudenal-thigh flap in, 764 skin flap in, 764 vaginal dilation for, 760–761, 760f, 761f vaginoplasty in, 761–765, 762f, 762t, 763f Vecchietti procedure for, 761 Nerve injury, laparoscopy-related, 667–669, 668f Netter’s syndrome. See Intrauterine adhesions Neubauer hemocytometer, for sperm concentration, 582 Neurapraxia, laparoscopy-related, 667 Neurectomy, presacral, 122, 663, 740 Neuropeptide Y, puberty and, 158 Neurosyphilis, 498t Neurotmesis, laparoscopy-related, 667 Nobox, 55
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Nonmaleficence, 147 Nonsteroidal anti-inflammatory drugs in abnormal uterine bleeding, 307 in dysmenorrhea, 202 in menstrual migraine, 343 Noonan’s syndrome, 236 NovaSure Endometrial Ablation System, 636t, 637 Nucleoplasmin 2, 63 Null hypothesis, 141 Number needed to treat, 140 Nutrition in infertility evaluation, 512 puberty and, 158
O
822
Obesity functional hyperandrogenism and, 278 hirsutism and, 268 ovulatory dysfunction in, 278 in polycystic ovary syndrome, 217–218 Oblique muscles, 115 Obstetric history, in infertility evaluation, 511 Obturator artery, 121 Obturator nerve, 119, 120f laparoscopy-related injury to, 668, 668f Octreotide in acromegaly, 314 in Cushing’s disease, 315 Odds, 139, 140t Odds ratio, 139, 140t Oil embolism, hysterosalpingography and, 435, 435f Olfactory neurons, 3t Oligo-ovulation, 30 abnormal uterine bleeding and, 300 Oligomenorrhea, 297 in adolescent, 203 in polycystic ovary syndrome, 265 recurrent pregnancy loss and, 610 Oligospermia, 98, 530–531, 532. See also Infertility, male One-way ANOVA (analysis of variance), 142 Oocyte(s), 54–55. See also Oogenesis activation of, 106–107 age-related quality of, 111 animal-vegetal axis of, 64 apoptosis of, 54, 64–65 for assisted reproductive technology, 586–589, 588f, 589f collection of, 586–589 bleeding with, 603 complications of, 603–604 infection after, 603–604 media for, 587 cortical reaction of, 106–107 cryopreservation of, 151–152, 490 cytoplasmic changes in, 62–63, 64 depletion of, 354 donor, for in vitro fertilization, 577 embryology of, 51–54, 173. See also Oogenesis environmental effects on, 64 epigenetic regulation of, 62–63 first polar body of, 588, 588f germinal vesicle of, 51, 52f grading of, 589 immature, 588, 588f maternal effect genes of, 63–64 maturation of, 51, 52f–53f, 58, 58f, 61, 62–63
Oocyte(s) (Continued) maturation of (Continued) endometriosis effect on, 736 in vitro, 491, 572, 589 meiotic arrest of, 51, 60, 61 meiotic competence of, 61 meiotic resumption in, 60–62 microtubule organizing center, 64 nuclear changes in, 62–63 polarity in, 64 polyspermy block by, 106–107 poor quality of, 51 resting pool of, 57, 58 retrieval of, for in vitro fertilization, 574, 574f second polar body of, 588, 589f sperm fusion with, 104–106, 104f toxic effects on, 64 transcriptional activity of, 62, 63 transforming growth factor β of, 55, 57 translational activity of, 62 zona pellucida of, 55, 105–106, 592 Oocyte-cumulus cell complex, assessment of, 587–589, 588f Oocyte-embryo transition, 63–64 Oocyte-specific linker histone, 63 Oogenesis, 51–67, 56f. See also Spermatogenesis apoptosis in, 54 connexin in, 60 conservation of, 51 cumulus cells in, 59–60 cyclin-dependent kinase 2 proteins in, 55 epigenetic regulation in, 62–63 folliculogenesis and, 55–57, 56f gap junctions in, 60 germinal vesicle in, 51, 52f historical perspective on, 51 meiotic arrest in, 51, 60, 61 meiotic resumption in, 60–62 meiotic spindle in, 61–62 metaphase-anaphase transition of, 51, 53f, 61 metaphase I of, 51, 52f metaphase II of, 51, 53f MutL proteins in, 54–55 MutS proteins in, 54–55 nuclear changes in, 62–63 primordial germ cells in, 51–54, 56f prophase I of, 54–55, 56f spindle assembly checkpoint proteins in, 61–62 zona pellucida in, 55 Oogonia, 54, 56f, 173 Oophorectomy, 663, 752–755, 753f in premenstrual syndrome, 342 Oophoritis lymphocytic, 289 mumps, 290 Opioids, endogenous in amenorrhea, 6 in gonadotropin-releasing hormone secretion, 6, 240 in polycystic ovary syndrome, 220 Optic chiasma, 5f, 311 tumor impingement on, 312 Oral contraceptives, 387–400 in abnormal uterine bleeding, 204–205, 306, 306t, 307 abnormal uterine bleeding and, 299t, 300, 395 acne and, 391 amenorrhea and, 243 benign breast disease and, 391
Oral contraceptives (Continued) birth defects and, 394 bone mineral density and, 391 breast cancer and, 394 breast symptoms with, 394 breastfeeding and, 395, 396 cancer-related fertility preservation and, 488 cardiovascular risks with, 392–394, 392t cervical cancer and, 394 coagulation changes with, 392 colorectal cancer and, 391 combination, 388t, 390 contraindications to, 306, 388t, 393 drug interactions with, 395, 395t dysmenorrhea and, 391 ectopic pregnancy and, 390 efficacy of, 390 endocervical polyps and, 299 endometrial atrophy and, 301 endometrial cancer and, 390 endometrial histology with, 126, 126f estrogens in, 388–389, 388f, 388t extended-use, 395–396 failures rates for, 390 fertility and, 394 formulations of, 388–390, 388t headache with, 394–395 in hirsutism, 270 historical perspective on, 387 in hyperprolactinemia, 259 insulin resistance and, 392 irregular bleeding and, 395 lipid changes with, 392 mechanism of action of, 390 in menstrual migraine, 344 metabolic changes with, 392 missed pills with, 395 myocardial infarction and, 393–394 nausea with, 394 noncontraceptive benefits of, 390–391 ovarian cancer and, 391 ovarian cysts and, 391 in ovulatory dysfunction, 284 patient selection for, 388 Pearl index of, 390 pelvic inflammatory disease and, 390 in polycystic ovary syndrome, 203, 225 postpartum, 395 in premenstrual syndrome, 341 progestin in, 388–389, 389f progestin-only, 396 rheumatoid arthritis and, 391 risks of, 392–394, 392t side effects of, 394–395 stroke and, 393 venous thromboembolism and, 392–393, 392t weight gain and, 395 Organic solvents, recurrent pregnancy loss and, 617 Oscillin, 106 Osteoclasts, 371 estrogen effects on, 372 testosterone effects on, 373 Osteomyelitis, transvaginal follicle aspiration and, 604 Osteopenia, anorexia nervosa and, 209 Osteoporosis, 371–381 age and, 373 biochemical markers in, 376, 376t biopsy in, 376–377 clinical evaluation of, 374–377, 375t, 376t
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Osteoporosis (Continued) definition of, 371 dual energy absorptiometry in, 375–376, 375t, 381 fracture in, 371, 372, 377, 377f reduction of, 378–381 glucocorticoid-induced, 374, 380 hormonal therapy and, 373 hyperparathyroidism and, 373 imaging in, 375–376, 375t, 377f, 377f medical disorders with, 372 pathophysiology of, 371–373, 374t patient history in, 374 physical examination in, 375 postmenopausal, 357–358, 373 raloxifene in, 363 tamoxifen in, 362–363 tibilone in, 363 pregnancy and, 373 prevention of, 377 screening for, 377 secondary, 374, 374t treatment of, 377–381 bisphosphonates in, 379 calcitonin in, 379 combination therapy in, 380 estrogen in, 378–379 investigational agents in, 381 monitoring of, 380–381 nonpharmacologic, 378 parathyroid hormone in, 379–380 pharmacologic, 378–380 selective estrogen receptor modulators in, 379 vitamin D deficiency and, 373 Osteoprotegerin, 372 Ovarian cancer, 748–750 CA-125 in, 750, 750t classification of, 748, 748t clomiphene citrate and, 560, 604 endometriosis and, 738 epithelial cell, 748–749, 748t, 749t fertility preservation in, 492. See also Cancer, fertility preservation in germ cell, 749, 749t intraoperative rupture of, 751 laparoscopy in, 750–751 laparotomy in, 750–751 oral contraceptives and, 391 preoperative evaluation of, 750, 750t sex cord–stromal cell, 750 surgical staging of, 751–752, 761t Ovarian cyst(s) aspiration of, 752 biopsy of, 752 cystectomy for, 752–755, 753f, 754f, 755f dermoid magnetic resonance imaging of, 472, 477f puncture of, 604 rupture of, 749 ultrasonography of, 455, 455f functional, 747–748 hemorrhagic, 472, 477f histology of, 132–133, 133f intraoperative rupture of, 751 laparoscopy in, 750–751, 751f, 752–755, 753f, 754f levonorgestrel-containing IUD and, 410 magnetic resonance imaging of, 472, 477f oophorectomy for, 752, 753f
Ovarian cyst(s) (Continued) oral contraceptives and, 391 postmenopausal, 454 pregnancy-related, 132, 133f preoperative evaluation of, 750–751, 751f theca-lutein, 132, 133f ultrasonography of, 454, 455, 455f, 748 Ovarian follicle(s). See also Oocyte(s); Oogenesis; Ovulation antral/Graffian, 56f, 57f, 58 count of, 570 development of, 58–59, 58f atresia of, 58 autonomous development of, 164 depletion of, 278, 292 development of, 55–59, 56f, 57f, 549–550, 550f recruitment of, 57–60, 57f, 58f, 59f ultrasonography of, 453, 453f Ovarian hyperstimulation syndrome, 560, 597–601, 598f classification of, 598–599, 599t clinical course of, 599 coasting prevention of, 599 diagnosis of, 600, 600t fluid therapy in, 600–601, 600t follicular aspiration in, 600 hemoconcentration in, 598 hospitalization for, 601 human chorionic gonadotropin withholding in, 599 hypovolemia in, 598 incidence of, 597 intravenous albumin in, 599–600 luteal phase support and, 600 luteolysis in, 600 management of, 600–601, 600t onset of, 599 paracentesis in, 601 pathogenesis of, 597–598 prevention of, 599–600 resolution of, 599 risk factors for, 598, 598t ultrasonography in, 448, 449f vascular endothelial growth factor in, 597–598 Ovarian ligament, 116f Ovariopexy, in torsion, 211 Ovary (ovaries). See also at Ovarian adrenergic innervation of, 28 agenesis of, 186 aging of, 287–288 anatomy of, 123–124 androgen-secreting tumors of, 266, 269 biopsy of, in premature ovarian failure, 292 cancer of. See Ovarian cancer chemotherapy effects on, 151–152, 290, 485–486, 486t cryopreservation of, 491, 492t cysts of. See Ovarian cyst(s); Polycystic ovary syndrome cytokines of, 27t, 28 development of, 95–96, 96f diminished reserve of, 569, 569f drilling of, 227, 284, 557 dysgenesis of, 185–186 dysgerminoma of, 132, 132f embryology of, 173, 287. See also Oogenesis evaluation of for in vitro fertilization, 569–571, 569f in infertility, 516, 516t, 520–521 preoperative, 750, 750t
Ovary (ovaries) (Continued) failure of. See also Ovulatory dysfunction; Polycystic ovary syndrome chemotherapy-related, 485–486, 486t. See also Cancer, fertility preservation in physiologic, 288. See also Menopause premature. See Premature ovarian failure fibroma of, 134–135, 135f, 750 gonadoblastoma of, 132, 132f granulosa cell tumors of, 134, 134f, 750 growth factors of, 27–28, 27t histology of in cyst, 132–133, 133f in fibromas, 134–135, 135f in gonadal dysgenesis, 132, 132f in granulosa cell tumors, 134, 134f in Sertoli-Leydig cell tumors, 135, 135f in sex cord-stromal tumors, 133–134, 133t, 134t in stromal hyperthecosis, 133, 133f in thecomas, 134, 134f hyperthecosis of, 133, 133f, 266 magnetic resonance imaging of, 462, 462f–463f, 472, 477f, 478, 479f–481f peptide hormones of, 6–7, 24–27, 25f, 25t, 27f, 27t polycystic. See Polycystic ovary syndrome postmenopausal, 454 pregnancy in, 722 radiation effects on, 290, 486–487, 487t reserve of, in infertility evaluation, 520–521 sclerocystic, 132–133, 133f Sertoli-Leydig cell tumors of, 135, 135f sex cord-stromal tumors of, 26, 133–134, 133t, 134t steroid cell tumors of, 135 steroidogenesis in, 7–10, 7f, 7t, 8f, 8t, 17–19, 19f, 20f. See also Androgen(s); Estrogen(s); Progesterone enzymes in, 18–19, 18t, 19f, 20f two-cell theory of, 7–8, 8f, 8t, 17 streak, 132, 132f supernumerary, 186 surgical injury to, premature ovarian failure and, 290 thecomas of, 134, 134f torsion of, 209–211, 210f, 290, 443 transplantation of, 491, 492t transposition of, 488–490 failure of, 490 laparoscopic, 489 lateral vs. medial, 488–489 success of, 489–490 technique of, 489, 489f tumors of, 747–750. See also Ovarian cancer and specific tumors precocious puberty and, 163–164 ultrasonography of, 455, 455f venous sampling from, 269 volume of, 124 wedge resection of, in polycystic ovary syndrome, 227 Ovulation, 11. See also Ovulatory dysfunction evaluation of, in infertility evaluation, 518–519, 518f induction of, 283–284, 550–561 in abnormal uterine bleeding, 306–307 adverse effects of, 559–560 aromatase inhibitors for, 557–559, 557t
823
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Ovulation (Continued) induction of (Continued) clomiphene citrate for, 550–555, 552f. See also Clomiphene citrate, ovulation induction with failure of, 568–569 gonadotropins for, 556–557 human chorionic gonadotropin for, 556 indications for, 550 insulin-sensitizing agents for, 555–556 metformin for, 555–556 multiple pregnancy and, 559–560 ovarian cancer and, 560 ovarian drilling for, 557 ovarian hyperstimulation syndrome and, 560. See also Ovarian hyperstimulation syndrome physiology of, 277, 549–550, 550f Ovulatory dysfunction, 277–285, 277f. See also Polycystic ovary syndrome abnormal uterine bleeding and, 299t, 300–301 androgen levels in, 282–283 classification of, 280, 280t, 550 congenital adrenal hyperplasia and, 278, 301 diagnosis of, 279–283, 280t, 282f gonadotropins in, 278, 281–282 gynecologic examination in, 281 hyperprolactinemia and, 301, 519 hypothalamus in, 277–278 hypothyroidism and, 301, 519 laboratory evaluation in, 281–282 luteal phase defect and, 278 luteinized unruptured follicle syndrome and, 278 ovarian disorders and, 278 patient history in, 280–281 physical examination in, 281 progestin challenge test in, 283 prolactin levels in, 281 thyrotropin levels in, 281 treatment of, 283–285. See also Ovulation, induction of
P
824
P-value, 141 Pain in adolescents, 211–212, 211t in ectopic pregnancy, 712, 720–721 in endometriosis, 119, 512–513, 735, 736–737, 738–740, 739t, 742 intrauterine device placement and, 413 in leiomyoma, 683 pelvic, 683 in pelvic adhesions, 782 premenstrual. See Premenstrual syndrome ultrasonography in, 443–444 Paired t-test, 142 Palmer’s point, 660, 661f Pap smear in infertility evaluation, 511, 516 in primary amenorrhea, 195 Paracentesis, in ovarian hyperstimulation syndrome, 601 Paracervical block, in hysteroscopic myomectomy, 631 ParaGard IUD, 406, 406f. See also Intrauterine device (IUD)
Paramesonephric (Müllerian) ducts congenital disorders of, 175f, 176–178, 235t. See also Mayer-Rokitansky-Küster-Hauser syndrome; Uterus, septate classification of, 648, 648t embryology of, 647–648 incidence of, 649 ultrasonography of, 454 embryology of, 171–172, 172f persistent, 185 Parameter, 137 estimation of, 140–141 Parathyroid hormone, in osteoporosis, 379–380 Parity, recurrent pregnancy loss and, 609 Patch, contraceptive, 397–398 Paternal leukocyte immunization, in recurrent pregnancy loss, 620 P450c17, in ovarian steroidogenesis, 8, 8f, 8t Pearson correlation coefficient, 139 Pegvisomant, in acromegaly, 314 Pelvic adhesions, 779–788, 780f chronic pain syndrome and, 782 complications of, 780–782, 781f de novo, 779, 785 definition of, 779 economic impact of, 780 fibrinolysis and, 783 foreign materials and, 783–784 hysterosalpingography in, 430, 432f infertility and, 515, 781 intestinal obstruction and, 781–782, 781f ischemia and, 783 pathophysiology of, 782–784, 783t peritoneal repair in, 782–783, 783t prevalence of, 779–780 prevention of, 784–788 adjuvant therapies in, 786–788, 786t, 787t anti-inflammatory drugs in, 788 antiadhesion barriers in, 786–787, 786t, 787t CO2 pneumoperitoneum and, 785 dextran in, 788 energy source and, 785 hemostasis technique and, 784 historical perspective on, 779 hyaluron-based agents in, 787 hydrofloatation in, 787–788 laparoscopy and, 784–785 mechanical barriers in, 787–788 plasminogen activator in, 787 second-look laparoscopy and, 786 tissue approximation technique and, 784 tissue handling technique and, 784 reformation of, 779, 785 reproductive disorders and, 781 risk factors for, 783–784 treatment of, 785, 785f laparoscopic, 663 pain and, 782 Pelvic diaphragm, 121–122, 122f Pelvic examination in ectopic pregnancy, 713 in precocious puberty, 161 Pelvic fascia, 124 Pelvic floor, 121–122, 122f Pelvic infection artificial insemination and, 545 transvaginal follicle aspiration and, 603–604
Pelvic inflammatory disease in adolescent, 212 Chlamydia antibody testing in, 435–436 hysterosalpingography and, 434 infertility and, 502 intrauterine device and, 411 oral contraceptives and, 390 pathogens in, 502 treatment of, 502 tubal occlusion and, 697, 697f ultrasonography in, 444 Pelvic ligaments, 124 Penile vibratory stimulation, 536, 585 Pergolide mesylate, in prolactinoma, 313 Periadnexal adhesions, 568, 705–707, 706f lysis of, 707 Perimenopause, 280t, 355 Perineal membrane, 122 Perineal pouches, 122 Peritoneal cavity, 117–118, 117f, 118f laproscopy-related mass spillage into, 753–755, 754f in pelvic adhesion formation, 782–783, 783t washings of, in laparoscopic cystectomy, 752 Peritoneal fluid in endometriosis, 733–734 on ultrasonography, 453 Peritoneal folds, 117–118, 117f, 118f, 124 Peritoneal graft, in neovagina creation, 764 Peritoneal inclusion cyst, 478, 480f–481f Peritoneal pouches, 118, 118f Peritoneum in endometriosis, 733–734, 733t parietal, 116 Peritonitis, chemical, 749 Peroneal nerve, cryomyolysis-related injury to, 692 Perrault’s syndrome, 245, 289, 291 Persistent müllerian duct syndrome, 98, 185 Pheochromocytoma, 321–322, 322t, 355 Pheromones, menstrual cycle and, 3t Phosphodiesterase 3A, 61 Phytoestrogens in menopause, 366 in osteoporosis, 381 Pinopodes, endometrial, 108, 111 Pinworms, in children, 196 Pioglitazone in hirsutism, 271 in polycystic ovary syndrome, 221–222, 226, 556 Piriformis, 119 Pituitary apoplexy, 317 Pituitary gland, 2f, 4–7, 311t adenoma of. See Adenoma, pituitary anatomy of, 311 anterior, 2f, 4, 5f, 6t infarction of, 244 postpartum necrosis of, 243–244, 317 radiation injury to, 244 blood supply of, 4 cells of, 4, 6t gonadotrophin secretion by. See Follicle-stimulating hormone (FSH); Luteinizing hormone (LH) infarction of, 244 opioid effects on, 6 pars intermedia of, 4 posterior, 2f, 4, 5f
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Placenta estriol secretion of, 21 estrogen production by, 319 Placental growth factor, in implantation, 111 Placental mosaicism, 95 Placentation, after adhesiolysis, 646 Platelet disorders, abnormal uterine bleeding in, 301–302 Plicae palmitate, 462, 462f–463f Plugs, for sterilization, 425, 426f Pneumoperitoneum, for laparoscopy, 669–670 Pneumothorax catamenial, 346, 741 laparoscopy-related, 670 Point estimate, 140 Point mutation, 86 Polar body biopsy of, 592, 593f first, 53f, 588, 588f second, 588, 589f Polycystic ovary syndrome, 217–228 acanthosis nigricans in, 218 acne in, 217 in adolescents, 202–203 adrenal function in, 221–222 alopecia in, 217 amenorrhea in, 166, 243 aromatase inhibitors in, 558 cancer in, 223 cardiovascular disease in, 222–223 clinical presentation of, 217–218 vs. Cushing’s syndrome, 223 depression in, 203 diabetes mellitus in, 222–223 diagnosis of, 202, 217, 281, 282f, 283 dopamine in, 220 endometrial cancer in, 223 fertility treatment in, 283–284. See also Ovulation, induction of follicle-stimulating hormone in, 218–219, 222 follistatin in, 27 G0/I0 (glucose-to-insulin) ratio in, 224, 224f gamma-aminobutyric acid in, 220 glucose tolerance test in, 223, 224–225, 224f gonadotropin-releasing hormone pulse generator in, 219–220 granulosa cell function in, 222 hirsutism in, 217, 227, 265–266, 265f histology of, 132–133, 133f homeostasis model assessment in, 224–225, 224f in vitro fertilization in, 568–569. See also In vitro fertilization hyperandrogenemia in, 220–222, 221f hyperinsulinemia in, 203, 221–222 infertility in, 218 inhibin B in, 26 insulin in, 220–221, 222 insulin-like growth factor I in, 220 insulin resistance in, 222, 224–225, 224f, 283–284, 301 laboratory evaluation of, 223–225 long-term health issues in, 285 luteinizing hormone in, 218–219, 219f, 222 menstrual abnormalities in, 218, 267 metabolic syndrome in, 222–223 miscarriage in, 218, 618 morphology of, 218, 218f obesity in, 217–218 opioids in, 220
Polycystic ovary syndrome (Continued) oral contraceptive effects on, 392 ovulatory dysfunction in, 222, 223, 278 pathogenesis of, 218–222 premature adrenarche and, 164–165 prevalence of, 217 vs. prolactinoma, 223 recurrent pregnancy loss and, 618 string of pearls pattern in, 447f, 451 theca cell function in, 220–221 treatment of, 225–227, 225f antiandrogens in, 225–225 hair removal in, 227 insulin-sensitizing agents in, 226–227, 226f oral contraceptives in, 225 ovarian surgery in, 227 weight loss in, 225 ultrasonography in, 218, 218f, 447f, 451, 455 Polymenorrhea, 297 Polymerase chain reaction, preimplantation, 592–593 Polyp(s) endocervical, 299 endometrial, 299, 569, 628 Polypectomy, hysteroscopic, 628 Polyspermy, blockage of, 106–107 Pomeroy technique, of tubal ligation, 419, 421f Population, natural, 508 Population mean, 137 Post-sterilization syndrome, 426 Postcoital test, in infertility evaluation, 520 Postembolization syndrome, 691 Potassium chloride, in ectopic pregnancy treatment, 721 Power, statistical, 142 Prader-Willi syndrome, 90t, 94 Prednisone in adrenal insufficiency, 318 in antiphospholipid antibody syndrome, 620 Pregnancy after adhesiolysis, 646–647 adrenal insufficiency and, 319 bone loss during, 373 bromocriptine during, 313 Cushing’s syndrome and, 321 ectopic. See Ectopic pregnancy endometrial histology in, 126–127, 127f, 128f Graves’ disease in, 329, 329t heterotopic, 456, 712 HIV infection and, 504–505 hyperaldosteronism and, 321 hyperemesis gravidarum in, 329, 329t hyperthyroidism and, 329–330, 329t hypothyroidism and, 329 hysterosalpingography and, 432 immunology of, 328 inhibin A in, 26 inhibin B in, 26 intrauterine device after, 413 intrauterine device and, 408, 408t late-onset congenital adrenal hyperplasia and, 319–320 leiomyoma and, 683, 684, 686 levothyroxine in, 329 loss of. See Abortion, spontaneous; Recurrent pregnancy loss luteoma in, 132, 133f lymphocytic hypophysitis in, 316–317 molar, 329, 329t
Pregnancy (Continued) multiple artificial insemination and, 546 assisted reproductive technology and, 601–603, 601f, 602t cerebral palsy and, 602 costs of, 602 infant mortality and, 602 maternal complications of, 602 oral ovulation agents and, 559–560 prematurity and, 602 prevention of, 603 small for gestational age infant and, 602 pheochromocytoma in, 322 pituitary adenoma in, 244–245 progesterone in, 22 prolactin levels in, 257 after radiation therapy, 487, 490 recurrent loss of, 609–622. See also Recurrent pregnancy loss septate uterus treatment and, 654–655 silent thyroiditis in, 329, 329t syphilis effect on, 499 tests for, 195 theca-lutein cyst in, 132, 133f thyroid cancer and, 330 thyroid disease and, 328–330 thyroid nodule in, 330 in Turner’s syndrome, 236 ultrasonography in, 448–449, 455 upright posture test in, 321 Preimplantation genetic diagnosis, 98–99, 592–593, 593f ethics of, 150–151 fluorescent in situ hybridization for, 593, 593f single-gene defects on, 592–593 Premature infant, assisted reproductive technology and, 602 Premature ovarian failure, 278, 287–293 amenorrhea and, 245–246 autoimmune causes of, 288t, 289–290 biopsy in, 292 conception and, 284–285 counseling for, 292, 292t definition of, 287 17,20-desmolase deficiency and, 288–289 diagnosis of, 290–292 fertility and, 290, 292–293 galactosemia and, 288 genetic factors in, 65–66, 288–289, 288t gonadotropin receptor polymorphism and, 288 hormone replacement in, 293 17α-hydroxylase deficiency and, 288–289 iatrogenic causes of, 288t, 290 idiopathic causes of, 288t, 290 imaging in, 292 infectious causes of, 288t, 290 inhibin polymorphism and, 288 laboratory evaluation in, 291–292, 291t management of, 292–293 mortality and, 293 ovulatory dysfunction and, 280t, 281 pathophysiology of, 288–290, 288t patient history in, 290–291 physical examination in, 290–291, 291t prevention of, 292 sex chromosome abnormalities and, 289 single-gene defects and, 288 treatment of, 284–285
825
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Premenstrual dysphoric disorders, 335, 336t Premenstrual syndrome, 335–342 antidepressants in, 341–342, 341f anxiolytics in, 341 communication strategies in, 340 danazol in, 342 definition of, 335 diagnosis of, 336–337, 336t, 337f diet in, 340–341 differential diagnosis of, 337 diuretics in, 341 epidemiology of, 335–336 etiology of, 337–340, 340f exercise in, 341 gonadotropin-releasing hormone agonists in, 342, 342f hot flashes in, 340 lifestyle modification in, 340–341 mastalgia in, 342 mefenamic acid in, 341 oral contraceptives in, 341 patient history in, 336–337, 338f, 339f physical examination in, 337 prospective symptoms record in, 336–337, 338f, 339f pyridoxine in, 341 surgical therapy in, 342 treatment of, 340–342 Presacral space, 122 Pressure lavage, under ultrasound guidance, 450 Primordial germ cells, 51–54, 56f migration of, 53 Pro-opiomelanocortin, 6 Progestasert IUD, 406 Progesterone, 1t, 9, 22 assay of, 24, 24t biosynthesis of, 19f, 20f, 22 in ectopic pregnancy, 714 endometriosis and, 733 leiomyoma and, 685–686, 685f in menstrual cycle, 10f, 11 metabolism of, 9, 22 midluteal, in clomiphene citrate–induced ovulation, 552–553 nongenomic actions of, 37–38 in ovulation evaluation, 518–519 structure of, 18f therapeutic in catamenial epilepsy, 344–345 in in vitro fertilization, 576 in menopause, 364 in premature ovarian failure, 246 in premenstrual asthma, 345 in recurrent pregnancy loss, 620 Progesterone receptors, 9, 36–37, 36f ligand binding to, 34–35, 34t Progestin in abnormal uterine bleeding, 306, 307 cancer-related fertility preservation and, 488 in delayed puberty, 167 in endometriosis, 739 in menopause, 364 in ovulatory dysfunction, 284 Progestin challenge test in ovulatory dysfunction, 283 in premature ovarian failure, 291 in secondary amenorrhea, 242, 248–249
Prolactin, 32–33, 253–254, 311t assay of, 33 behavioral stimulation of, 257 big, 253 big big, 253 biosynthesis of, 32–33 in delayed puberty, 166 dopamine inhibition of, 312 ectopic production of, 257 neuroregulation of, 253–254, 254t in ovulatory dysfunction, 281, 519 physiology of, 32, 312 pregnancy-related levels of, 257 secretion of, 253–254 serum, 33, 258 structure of, 32 Prolactin receptors, 42–43 Prolactin-releasing factors, 253, 254t Prolactinoma, 33, 257, 312–313. See also Hyperprolactinemia amenorrhea and, 243, 244–245 vs. polycystic ovary syndrome, 223 transsphenoidal surgery in, 313 treatment of, 313 Proliferin, in implantation, 111 Proliferin-related protein, in implantation, 111 Prophase I, of oogenesis, 54–55 Propylthiouracil, in hyperthyroidism, 327–328 Prospective Record of the Impact and Severity of Menstrual systems, 336–337, 338f, 339f Prostacyclin, in implantation, 109 Prostaglandin(s) in endometriosis, 737 in implantation, 109 Prostaglandin E2, in cumulus expansion, 60 Prostaglandin F2β, in dysmenorrhea, 201, 202f Protein C deficiency, recurrent pregnancy loss and, 615t, 616, 619 Protein S deficiency, recurrent pregnancy loss and, 615t, 616, 619 Prothrombin G20210A mutation, recurrent pregnancy loss and, 615, 615t, 619 Pseudogestational sac, 456, 713 Pseudohermaphroditism counseling for, 187–188 evaluation of, 186–187 female, 180–182, 181f gender assignment in, 187 male, 182–185 5-α-reductase type 2 deficiency and, 183 androgen insensitivity syndrome and, 183 enzymatic disorders and, 184–185 Leydig cell hypoplasia and, 183–184 malformation syndromes with, 186 Pseudomosaicism, 95 Pseudomyxoma peritonei, 749 Psoas major, 119 Psoas minor, 119 Psoriasis, vulvar, in children, 197 Psychiatric disorders, premenstrual magnification of, 336 Puberty, 157–167. See also Adolescents adrenarche in, 158f, 159, 159f delayed, 165–167, 165t bone age in, 166 constitutional (physiologic), 165 evaluation of, 166 hypogonadism and, 165 imaging in, 166
Puberty (Continued) delayed (Continued) laboratory evaluation of, 166 patient history in, 166 physical examination in, 166 psychological implications of, 167 treatment of, 166–167 estrogen at, 20 growth at, 159 hypothalamic-pituitary-ovarian axis in, 157–158, 157f menarche in, 159, 159f normal, 157–160, 157f, 159f, 160f nutritional status and, 158 onset of, 158–159, 159f patient evaluation at, 159–160 physical examination at, 160 precocious, 160–163, 160t adult height and, 160 autonomous ovarian estrogen production and, 163–164 bone age in, 162 central, 160–163, 160t, 162f, 163t CNS lesions and, 161 in congenital adrenal hyperplasia, 164 diagnosis of, 160–162 gonadotropin-releasing hormone stimulation in, 161 heterosexual, 160t hypothalamic suppression in, 162–163 imaging in, 161–162 laboratory findings in, 161 in McCune-Albright syndrome, 164 patient history in, 161 pelvic examination in, 161 peripheral, 160t, 162f, 163–164 physical examination in, 161 premature adrenarche and, 164–165 premature thelarche and, 164 recombinant growth hormone in, 163 serum luteinizing hormone in, 161 treatment of, 162–163, 163t psychosocial concerns at, 160 sexuality and, 160 Tanner stages of, 158–159, 158f, 159f, 194 thelarche in, 158, 158f, 159f Pubic hair, development of, 158f, 159, 159f premature, 164–165 Pudenal-thigh flap, in neovagina creation, 764 Pudendal artery, 120f Pudendal nerve, 119 Pulmonary leiomyomatosis, 684–685 Pulse oximetry, in laparoscopy, 669 Pyramidalis muscle, 115 Pyridoxine, in premenstrual syndrome, 341
Q Quadratus lumborus, 119
R Radiation exposure hysterosalpingography and, 434–435 recurrent pregnancy loss and, 617 Radiation therapy in acromegaly, 314 gonadal effects of, 290, 486–487, 487t, 493
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Radiation therapy (Continued) pregnancy after, 487, 490 uterine effects of, 487 Radioimmunoassay, 23 Radioiodine, in hyperthyroidism, 328 Radionuclide imaging, vs. hysterosalpingography, 436 Raloxifene, 36 endometrial effects of, 300 in leiomyoma, 687–688 in postmenopausal osteoporosis, 363 Random sample, 137 Randomized complete block design, 138, 138t Range, 139 RANTES (regulated on activation, normal T-cell expressed and secreted) factor, in endometriosis, 734 Rapid plasma reagin (RPR) test, 499 Reactive oxygen species, in endometriosis, 734 Receiver operating characteristic (ROC) curve, 140 Receptors downregulation of, 39 G protein-coupled, 38–42, 40f. See also Follicle-stimulating hormone (FSH) receptors; Gonadotropin-releasing hormone (GnRH) receptors; Luteinizing hormone (LH) receptors peptide hormone, 40f, 42–43 steroid hormone, 33–43. See also Androgen receptors; Estrogen receptors; Progesterone receptors amino-terminal transactivation domain of, 34 carboxy-terminal ligand-binding domain of, 34 central DNA-binding domain of, 34 hinge region of, 34 ligand binding to, 34–35, 34t orphan, 33t type 1, 33–34, 33t type 2, 33t, 34 tyrosine kinase, 42–43 Rectal artery, 120f, 122, 123 Recto-uterine pouch, 118, 118f, 123 Rectovaginal septum, 118 Rectum, 122, 462, 462f–463f Rectus abdominis, 115 Rectus sheath, 115 Recurrent pregnancy loss, 609–622 after adhesiolysis, 647 alcohol consumption and, 616–617, 621 alloimmune factors in, 614 anatomic factors in, 612, 612f evaluation of, 618–619 treatment of, 620 aneuploidy and, 610 antinuclear antibodies and, 614 antiphospholipid antibodies and, 613–614, 619, 619t, 620 antithrombin deficiency and, 615t, 616 antithyroid antibodies and, 614 caffeine intake and, 617 cervical incompetence and, 612 chromosomal disorders and, 610–611 cigarette smoking and, 616 congenital uterine malformations and, 612, 612f, 620 cytokine shift and, 614 day 3 FSH levels and, 611, 618 definition of, 609 diethylstilbestrol exposure and, 612 endocrinologic factors in, 611, 618, 620
Recurrent pregnancy loss (Continued) environmental exposures and, 617, 621 etiology of, 610–616, 612f, 615t evaluation of, 617–619, 618t, 619t factor V Leiden mutation and, 615, 615t, 619 genetic counseling in, 619 genetic factors in, 610–611, 617–618, 619 gestational age and, 610 heavy metal exposure and, 617 hyperhomocysteinemia and, 615–616, 615t, 619, 621 hyperprolactinemia and, 611, 620 hypothyroidism and, 611 immunologic factors in, 612–616, 619, 619t, 620–621 immunosuppression and, 614, 615 infection and, 615, 619, 621 insulin resistance and, 611 intrauterine masses and, 612 ionizing radiation and, 617 leiomyoma and, 612, 620 luteal phase defect and, 611, 620 male factors and, 616 maternal age and, 609 mechanical barrier effect and, 614 MHC gene expression and, 614 microbiologic factors in, 615, 619, 621 oligomenorrhea and, 610 organic solvent exposure and, 617 parity and, 609 protein C deficiency and, 615t, 616, 619 protein S deficiency and, 615t, 616, 619 prothrombin G20210A mutation and, 615, 615t, 619 psychological aspects of, 621 ring chromosomes and, 610 risk for, 609–610 secondary risk factors for, 616 septate uterus treatment and, 655 single-gene mutations and, 610 sonohysterography in, 448 systemic lupus erythematosus and, 613 thrombophilic factors in, 615–616, 615t, 619, 621 treatment of, 619–621 ultrasonography in, 447–448 uterine adhesions and, 612 X-inactivation and, 610–611 5-α-Reductase type 2 deficiency, male pseudohermaphroditism and, 183 Reliability coefficient, 141 Renal cell cancer, leiomyomatosis and, 684 Repeated measures design, 138–139, 138t Replication, in experimental design, 137 Research hypothesis, 141 Resectoscope, 626, 627 Resorption pit, of bone, 371 Rheumatoid arthritis menstrual cycle and, 346 oral contraceptive effects on, 391 Ringer’s solution, for hysteroscopy, 627 Risedronate, in osteoporosis, 379 Risk, 139, 140t Risk difference, 140 Risk ratio (relative risk), 139, 140t Robertsonian translocation, preimplantation diagnosis of, 99 Rosiglitazone in hirsutism, 271 in polycystic ovary syndrome, 556
Round ligament, 116f, 118f, 124 RU-486, 37 Rubella testing, in infertility evaluation, 516 Rubinstein-Taybi syndrome, 90t Rudimentary uterine horn, 768–769, 768f
S Sacral artery, 120f Sacral nerve, 119 Saline infusion sonography. See Sonohysterography Saline suppression test, in hyperaldosteronism, 321 Salpingectomy, in distal tubal occlusion, 703–705 Salpingitis female infertility and, 503 histology of, 130–131, 131f trichomoniasis and, 499 tuberculosis, 131–132 Salpingitis isthmica nodosa hysterosalpingography in, 430, 431f proximal tubal occlusion and, 699–700 Salpingography, selective, in proximal tubal occlusion, 434, 434f, 699, 699f, 699t Salpingoscopy vs. hysterosalpingography, 436 in tubal abnormalities, 698 Salpingostomy, in distal tubal occlusion, 703, 705f, 705t Sample, 137, 138 Sample mean, 137 Schistosomiasis, tubal, 503 Sciatic nerve, 119 endometriosis of, 742, 742f laparoscopy-related injury to, 669 Scp3, 55 Scrotum, ultrasonography of, 532, 534f Selective estrogen receptor-B agonists, in endometriosis, 740 Selective estrogen receptor modulator, 550. See also Clomiphene citrate abnormal uterine bleeding and, 300 in leiomyoma, 687–688 in McCune-Albright syndrome, 164 in menopause, 362–363 in osteoporosis, 379, 381 Selective progesterone receptor modulator, in leiomyoma, 688, 688f Selective serotonin reuptake inhibitors in menopause, 364, 364t in premenstrual syndrome, 341–342, 341f Sella turcica, 5f Semen. See also Sperm analysis of, 517, 530–531, 531t, 540, 581, 582–583 appearance of, 582 collection of, 531, 581–582 cryopreservation of, 493 liquefaction of, 582 pH of, 582 sperm concentration in, 582–583 viscosity of, 582 volume of, 582 Seminal vesicle, aspiration of, 536 Seminal vesiculography, in ejaculatory duct obstruction, 797 Seprafilm, in adhesion prevention, 787 Serosa tubal, 123 uterine, 123
827
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Serotonin, estrogen levels and, 340, 340f Sertoli cells, 73–74 Sertoli-Leydig cell tumor, 135, 135f Sex cord-stromal tumors, 26, 133–134, 133t, 134t, 750 Sex determination, 95–97, 96f Sex-hormone-binding globulin, 22–23 estradiol binding to, 8 saliva measurement of, 24 saturation analysis of, 23 serum, 23 testosterone levels and, 264, 264t Sexual abuse, 196, 197, 198 Sexual dysfunction, in infertility evaluation, 512 Sexual history in female infertility evaluation, 512–513, 512f in male infertility evaluation, 529 Sexual orientation, in infertility evaluation, 513 Sexually transmitted diseases female infertility and, 497–505, 497t, 498t, 517 clinical manifestations of, 501–503, 502t evaluation of, 503–504 intrauterine devices and, 411 SF1 gene, 97, 173 Sheehan’s syndrome, 243–244, 317 Sheep BMP15 mutation in, 57f GDF9 mutation in, 57f Shift mutation, 86 Sickle cell anemia screening, in infertility evaluation, 511, 511t Sildenafil, in in vitro fertilization, 573 Silent mutation, 86 Simvastatin, in osteoporosis, 380 Single-cell gel electrophoresis test, for sperm, 584 Single-nucleotide polymorphism, 86 Skin androgen receptors of, 265 examination of, in infertility evaluation, 514–515 Skin flap, in neovagina creation, 764 Sleep disorders, hot flashes and, 357 SMAD proteins, 42f, 43, 53 Small for gestational age infant, assisted reproductive technology and, 602 Small intestine, laparoscopy-related injury to, 674 Smith-Lemli-Opitz syndrome, type I, 186 Smith-Magenis syndrome, 90t Social history in female infertility evaluation, 512 in male infertility evaluation, 529 Sodium chloride fluid, for hysteroscopy, 627 Solvents, recurrent pregnancy loss and, 617 Somatic mosaicism, 95 Somatostatin analogues in acromegaly, 314 in Cushing’s disease, 315 Somatotrophs, 6t Sonohysterography in abnormal uterine bleeding, 304, 445–446, 445f air-contrast, 448 catheter for, 451–452, 451f in endometrial cancer, 446–447 in in vitro fertilization, 448 vs. hysterosalpingography, 436 in infertility evaluation, 447, 517 intraoperative, 450 in leiomyoma, 443, 443f operative, 449–450 problems with, 452, 452f
Sonohysterography (Continued) in recurrent pregnancy loss, 448, 618 risks of, 450 saline for, 452 screening, 446 in septate uterus, 650–651 spontaneous, 450 technique of, 451–452, 451f timing of, 450 vs. ultrasonography, 442 in uterine adhesions, 643 Sonohysterosalpingography (hystero-contrast-sonography, HyCoSy) vs. hysterosalpingography, 436 in infertility evaluation, 517 in tubal abnormalities, 698 Sonosalpinography, 448 tubal cannulation during, 450 Sorbitol, for hysteroscopy, 627, 679 SOX9 gene, 97 Soy, in menopause, 366 sp56, 105 sp95, 105 Sperm. See also Spermatogenesis acrosome reaction for, 584 analysis of, 530–531, 531t anatomy of, 74f antibodies to, 531, 540, 545, 546, 568 for artificial insemination, 542–543, 543t, 544–545. See also Artificial insemination capacitation of, 590 chromatin structure assay for, 584 collection of, 799–801 after electroejaculation, 585 from epididymis, 585–586 microdissection in, 801, 801f after retrograde ejaculation, 585 surgical, 585–586 from testis, 586, 800–801 from urine, 585 after vibratory stimulation, 585 concentration of, 582–583 cryopreservation of, 493, 586 density gradient separation of, 543, 585 DNA damage tests for, 545 eosin-nigrosin test for, 583 forward progression of, 583 functional tests for, 583–584 glass wool filtration of, 543 grading of, 583 hamster egg penetration assay for, 584 head of, 583 in vitro oocyte insemination with, 589–590, 591f hypo-osmotic swelling test for, 545, 583 intracytoplasmatic injection of, 590, 591f microsurgical epididymal aspiration of, 585–586, 800 morphology of, 531, 583, 616 motility of, 583 percutaneous epididymal aspiration of, 800 in recurrent pregnancy loss, 616 single-cell gel electrophoresis test for, 584 swim-up separation of, 543, 584–585 testicular aspiration of, 800 transplantation of, 493 urinary, 585 vaginal lubricant effect on, 512 viability of, 583
Sperm (Continued) washing of, 505, 543, 584 zona pellucida binding assay for, 584 Spermatocytogenesis, 75 Spermatogenesis, 74–78, 75f, 76f, 102. See also Oogenesis acrosomal phase of, 78 cap phase of, 78 chemotherapy effect on, 493 cycle (wave) of, 77 disturbances of, 79 efficiency of, 77–78 extrinsic regulation of, 79 Golgi phase of, 77–78 intrinsic regulation of, 79 maturation phase of, 78 regulation of, 79 stages of, 77 Spermatogenic waves, 77 Spermatogonia. See also Sperm; Spermatogenesis differentiation of, 75, 75f meiosis of, 76 mitosis of, 75–76 proliferation of, 75, 75f types of, 75 Spermatozoa, 74f, 78–79 acrosome of, 74f, 78 acrosome reaction of, 81, 103 capacitation of, 81, 102–103 cervical mucus entry by, 80–81 cumulus oophorus penetration by, 104–105, 104f endpiece of, 74f, 78–79 epididymal storage of, 80 epididymal transport of, 79–80 head of, 74f, 78 hyperactivation of, 103 maturation of, 80 neck of, 74f, 78 oocyte fusion with, 106 tail of, 74f, 78 transport of, 102–103 zona pellucida interaction with, 105–106 Spermiation, 77 Spermiogenesis, 76, 76f Sphingosine-1-phosphate, cancer-related fertility preservation and, 488 Spinal cord injury, male infertility and, 527 Spindle assembly checkpoint, 61–62 Spironolactone in hirsutism, 271 male infertility and, 529 in polycystic ovary syndrome, 203, 225 Spleen, on laparoscopy, 662, 662f Spo11, 55 SRY gene, 96, 96f, 173 Standard deviation, 139 Standard error, 141 Statins, in osteoporosis, 380 Statistics, 137–144 analysis of variance in, 142 comparison of means in, 142 comparison of proportions, 143, 143t confidence interval in, 140–141 contingency table in, 139, 140, 140t definition of, 137 for diagnostic test evaluation, 140, 140t estimation in, 140–141 experimental design and, 137–139, 138t goal of, 137
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Statistics (Continued) logistic regression equation in, 143, 143t multiple regression analysis in, 142–143 P-value in, 141 power in, 142 ROC (receiver operating characteristic) curve in, 140 for survival rates, 143–144 test of hypotheses in, 141–142 type I error in, 141 type II error in, 141 variables in, 137, 139 Stem cell factor, 53 Stem cell research, ethics of, 152–154 Sterilization, tubal, 417–427 chemical agents for, 425 complications of, 425–426 electrocoagulation for, 425 failure of, 425–426 fimbriectomy for, 419, 422f historical perspective on, 417 in vitro fertilization after, 568 hysterectomy risk and, 426 hysteroscopic, 425, 426f informed consent for, 417–418, 417t interval, 418 Irving technique of, 418, 420f Kroener technique of, 419, 422f laparoscopic, 419, 421, 423–424, 662 bipolar, 421, 423, 423f clip, 424, 424f Falope ring, 423–424, 423f unipolar, 419, 421 under local anesthesia, 424–425 Madlener technique of, 418, 419f menstrual changes with, 426 plug devices for, 425, 426f Pomeroy technique of, 419, 421f post-sterilization syndrome and, 426 postpartum, 418 regret after, 418, 418t, 426 reversal of, 104, 700–703, 700f, 701f, 702f, 703t timing of, 418 Uchida technique of, 419, 422f vaginal approach to, 418, 422f Steroid cell tumors, 135 Steroidogenesis, ovarian, 7–10, 7f, 7t, 8f, 8t, 17–19, 19f, 20f. See also Androgen(s); Estrogen(s); Progesterone enzymes in, 18–19, 18t, 19f, 20f two-cell theory of, 7–8, 8f, 8t, 17 Steroidogenic acute regulatory (StAR) protein, 17 Stevens-Johnson syndrome, 197 Stomach, laparoscopy-related injury to, 673–674 Strassman metroplasty, 768 Streak gonads, 97, 132, 132f, 185 Stress amenorrhea and, 6, 240–241, 240t infertility and, 509 menstrual cycle and, 3t Stroke oral contraceptives and, 393 postmenopausal, 358 Strontium, in osteoporosis, 380 Struma ovarii, 749 Subcostal nerves, 116 Subfertility, 507t, 508–509. See also Infertility Suckling, 254 Sumatriptan, in menstrual migraine, 343–344
Superovulation, 57, 65. See also Ovarian hyperstimulation syndrome Surgical history in female infertility evaluation, 511 in male infertility evaluation, 528–529 Survival function, 143 Survival rate, 143–144 Suspensory ligament (infundibulopelvic) ligament, 124 Swim-up technique, for sperm, 543, 584–585 Swyer syndrome, 185, 236 delayed puberty in, 165 premature ovarian failure in, 289 Synechiae. See Intrauterine adhesions Syphilis infertility and, 499, 517 treatment of, 498t Systemic lupus erythematosus, recurrent pregnancy loss and, 613
T t-test, 142 Tamoxifen, 36 in breast cancer, 446 endometrial effects of, 300, 446 in in vitro fertilization, 490 in leiomyoma, 687–688 levonorgestrel-containing IUD with, 409–410 in McCune-Albright syndrome, 164 in menopause, 362–363 Tanner stages, 158–159, 158f, 159f, 196 Tattooing, in infertility evaluation, 514 Tay-Sachs disease screening, in infertility evaluation, 511, 511t Telearche, 159f Telomeres, 86, 87f, 90 Teratoma, 749, 749t Teriparatide, in osteoporosis, 379–380 Terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate-nick end labeling (TUNEL) test, 545 Testicular feminization. See Androgen insensitivity syndrome Testis (testes) anabolic steroid effects on, 527 anatomy of, 73, 74f biopsy of, in male infertility, 535–536, 535f, 793 chemotherapy effects on, 527 cryopreservation of, 493 development of, 95–96, 96f embryology of, 173 immune status of, 79 Leydig cells of, 73 radiation effects on, 493 Sertoli cells of, 73–74 sperm extraction from, 586, 800–801 supporting cells of, 73–74 Testosterone albumin-bound, 23 assay of, 24, 24t in female infertility evaluation, 520 hair growth and, 264–265, 265f, 265t in hirsutism, 268 in male infertility evaluation, 531 metabolism of, 22 ovarian, 9, 22 serum, in female, 10, 24, 24t
Testosterone (Continued) skeletal effects of, 372–373 structure of, 18f suppression of, 493 Tetraploidy, 87 Thalassemia screening, in infertility evaluation, 511, 511t Theca cells luteinizing hormone receptors of, 6 in polycystic ovary syndrome, 220–221 steroid secretion by, 9, 22 Theca-lutein cells, steroid secretion by. See Progesterone Thecoma, 134, 134f Thelarche, 158, 158f premature, 164 ThermaChoice UBT System, 636, 636t Thermal injury, laparoscopy-related, 674 Thionamides, in hyperthyroidism, 327–328 Thoracoabdominal nerves, 116 Thorax, endometriosis of, 741 Thrifty phenotype hypothesis, 222 Thrombocytopenic purpura, idiopathic, abnormal uterine bleeding in, 302 Thrombophilia, recurrent pregnancy loss and, 615–616, 615t, 619, 621 Thyroglobulin, in hypothyroidism, 326 Thyroid gland, 323–330 cancer of, 330, 356 disease of. See also Hyperthyroidism; Hypothyroidism fertility and, 324–325 screening for, 324, 324t fetal, 328–329, 330 hormones of, 323–324, 326, 328 physiology of, 323–324 pituitary regulation of, 324 in pregnancy, 327 solitary nodule of, 330 Thyroid hormone–binding protein, abnormalities of, 323 Thyroiditis postpartum, 330 silent, 329, 329t Thyrotoxicosis. See Hyperthyroidism Thyrotrophs, 6t Thyrotropin, 311t, 324 deficiency of, 316 in hyperthyroidism, 327 in hypothyroidism, 326 normal values of, 324 in ovulatory dysfunction, 281, 519 Thyrotropin receptor, antibodies to, 326 Thyrotropin-releasing hormone, prolactin secretion and, 519 Thyroxine (T4), 323–324 in hypothyroidism, 326 in pregnancy, 328 Tibolone, in postmenopausal osteoporosis, 363 Tissue inhibitor of metalloproteinases, 110–111 Tompkins metroplasty, 653–654 Tranexamic acid, in abnormal uterine bleeding, 306 Transcription factors, in folliculogenesis, 55, 56f Transdermal contraceptive patch, 397–398 Transforming growth factor-α, 27t, 28 Transforming growth factor-β, 25f, 55, 57 Transhydrolaparoscopy, in tubal abnormalities, 698
829
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Transplantation ovary, 491, 492t sperm, 493 Transsphenoidal surgery in Cushing’s disease, 315 in prolactinoma, 313 Transvaginal hydrolaparoscopy, vs. hysterosalpingography, 436 Transversalis fascia, 115 Transversus abdominis muscle, 115 Trauma head, 244 hymenal, 196 Treponema pallidum infection, 498t, 499 Trichomoniasis, 498t, 499–500 Trigger points, abdominal, in adolescent, 212 Triiodothyronine (T3), 323–324 in hypothyroidism, 326 in pregnancy, 328 Trinucleotide repeat disorders, 94–95, 94t Triploidy, 87 Triptorelin, 4t Trisomy 13, 88t Trisomy 18, 88t Trisomy 21, 88t, 593, 593f Troglitazone, in polycystic ovary syndrome, 226–227, 226f, 556 Trophinin, in implantation, 108 Trophoblast, 110–111 maternal immune response to, 614 mechanical barrier effect of, 614 Trophoblast immune infusion, in recurrent pregnancy loss, 620 Tubal ligation. See Sterilization Tubal ring, 456, 456f Tuberculosis endometrial, 126, 127f female infertility and, 501, 510 intrauterine adhesions and, 647 tubal, 131–132, 503, 510 γ-Tubulin, 107 Tumor necrosis factor, in endometriosis, 734 Tumor necrosis factor α, estrogen effects on, 372 TUNEL (terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate-nick end labeling) test, 545 Turner’s syndrome, 88t, 185, 235 clinical features of, 236 delayed puberty in, 165, 166 mosaicism in, 87, 95 pregnancy in, 236 premature ovarian failure in, 289 Two-way ANOVA (analysis of variance), 142 Tyrosine kinase receptors, 42–43
U
830
Uchida technique, of tubal ligation, 419, 422f Ulcer, genital, in Behçet’s disease, 198 Ulcerative colitis, in adolescent, 212 Ultrasonography, 441–457 A-mode, 441 in abnormal uterine bleeding, 304, 444–446, 445f in adenomyosis, 454 in adnexal pathology, 455 in asymptomatic women, 446 B-mode, 441 in bicornuate uterus, 177, 447–448, 447f
Ultrasonography (Continued) in breast cancer patients, 446 discriminatory zone β-hCG and, 455–456 Doppler, 441, 442f dynamic range for, 442 in ectopic pregnancy, 455–456, 456f, 713 in embryo transfer, 576 in endometrial abnormalities, 454 in endometrial carcinoma, 446–447 equipment parameters for, 441–442 in fallopian tube evaluation, 448 fetal, 449 four-dimensional, 441 frequency for, 441–442 gain for, 442 in hirsutism, 269 in hydrosalpinges, 444, 444f before in vitro fertilization, 570 in in vitro fertilization, 448, 449f, 573 vs. hysterosalpingography, 436 in hysteroscopic myomectomy, 632 indications for, 442–450, 443t in infertility, 447–448, 447f, 517 intraperitoneal fluid on, 451 in intrauterine adhesions, 454 in lost IUD, 444 M-mode, 441 in Mayer-Rokitansky-Küster-Hauser syndrome, 760 modes of, 441 in Müllerian duct anomalies, 454 normal findings on, 452–454, 453f operative, 449–450 in ovarian cyst, 748 in ovarian hyperstimulation, 448, 449f, 598f in ovarian mass, 455, 455f in ovarian torsion, 209–211, 210f, 443 in pelvic inflammatory disease, 444 in pelvic mass, 442–442, 443t in pelvic pain, 443–444 peritoneal fluid on, 453 in polycystic ovary syndrome, 218, 218f, 447, 447f, 451 of postchemotherapy ovarian reserve, 486 in postmenopausal woman, 446, 454 power level for, 442 in pregnancy, 448–449, 455 in premature ovarian failure, 292 premedication for, 450 pressure lavage with, 450 probe array for, 441 of pseudogestational sac, 456 in recurrent pregnancy loss, 447–448, 618–619 risks of, 450 in salpingitis, 455 screening, 446 of scrotum, 532, 534f in septate uterus, 178 vs. sonohysterography, 442 three-dimensional, 441 in thyroid disease, 326 timing of, 450–451 transabdominal, 442 transrectal, in male infertility, 534, 535f, 793 transvaginal, 442, 451 in abnormal uterine bleeding, 304 in adenomyosis, 299 in artificial insemination, 542 in ovarian cystadenoma, 749 screening, 446
Ultrasonography (Continued) transvaginal (Continued) in secondary amenorrhea, 249 in septate uterus, 650–651, 650f in uterine adhesions, 643 tubal ring on, 456, 456f in uterine hypoplasia, 454 in uterine leiomyoma, 443, 443f, 454 in vaginal agenesis, 176 in varicocele, 532, 534f Umbilical artery, 120f, 121 Umbilical fold lateral, 117 medial, 117, 117f Uniparental disomy, 94 Ureaplasmas, female infertility and, 500 Ureter, 121, 121f endometriosis of, 736, 741–742 laparoscopy-related injury to, 676 Urethra, 462, 462f–463f, 481–482, 483f Urethral diverticulum, 482, 483f Urethritis, nongonococcal, 500 Urinary tract infection, postmenopausal, 357 Urogenital sinus, 173 Uterine artery, 120f, 121, 123 Uterine artery embolization, 690–691, 690f, 691f Uterine artery ligation, 692 Uterine bleeding. See Abnormal uterine bleeding Uterosacral ligament, 124 Uterosacral nerve ablation in dysmenorrhea, 663 in endometriosis, 740 Uterus abnormal bleeding from. See Abnormal uterine bleeding abnormalities of, 759, 759t in infertility evaluation, 515, 516t adhesions of. See Intrauterine adhesions agenesis of, 174, 175f, 176, 464, 464f anatomy of, 123 arcuate, 175f, 176, 178, 464, 464f bicornuate, 175f, 176, 177–178, 767–768, 767f magnetic resonance imaging of, 464–467, 467f ultrasonography of, 447–448, 447f, 454 congenital malformations of, 174–188, 175f, 647–655, 767–769 classification of, 648, 648t diagnosis of, 650–651, 650f genetics of, 648 incidence of, 648–649 pathogenesis of, 176–180, 647–648, 649–650 recurrent pregnancy loss and, 612, 612f, 620 DES-related hypoplasia of, 175f, 176, 178–179 hysterosalpingography in, 429, 431f didelphic, 768 embryology of, 171–172 evaluation of, for in vitro fertilization, 569 fibroid of. See Leiomyoma hypoplasia of, 174, 175f, 176, 178–179, 454 hysterosalpingography of, 429, 430f. See also Hysterosalpingography magnetic resonance imaging of, 462, 462f–463f masses of, recurrent pregnancy loss and, 612, 620 noncommunicating rudimentary horn of, 768–769, 768f perforation of hysteroscopy and, 646, 654, 678 intrauterine device and, 414 radiation effects on, 487
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Uterus (Continued) rudimentary horn of, 768–769, 768f septate, 175f, 176, 178, 647–655, 767 vs. bicornuate uterus, 454, 768 classification of, 648, 648t diagnosis of, 650–651, 650f embryology of, 647–648 etiology of, 648 hysterosalpingography in, 431, 650, 651 incidence of, 649 magnetic resonance imaging in, 464–467, 465f, 466f, 651 pathophysiology of, 649–650 recurrent pregnancy loss and, 612, 612f, 620 sonohysterography in, 650 surgical treatment of, 651–654 ultrasonography in, 650–651, 650f ultrasonography of, 452–454, 453f unicornuate, 175, 175f, 176–177, 464, 464f, 768–769 Uterus bicornis bicollis, 177 Uterus bicornis unicollis, 177 Uterus didelphys, 175, 175f, 177, 465, 468f–470f
V Vagina, 123 agenesis of, 174, 175f, 176 atresia of, 179–180 creation of. See Neovagina diethylstilbestrol-related anomalies of, 178–179 dilation of, in neovagina creation, 760–761, 760f, 761f discharge from, in children, 195, 196 embryology of, 172–173 embryonal carcinoma of, 198 magnetic resonance imaging of, 462, 462f–463f postmenopausal, 357 septum. See Vaginal septum topical estrogen for, 362, 362t Vaginal artery, 120f, 121 Vaginal bleeding, in children, 196–197 Vaginal lubricants, in infertility evaluation, 512 Vaginal ring, contraceptive, 398 Vaginal septum longitudinal, 769–770 nonobstructing, 769, 769f obstructing, 769–770, 769f transverse, 179, 770–772, 771f clinical presentation of, 771 diagnosis of, 771 surgical removal of, 771–772, 772f thick, 772 Z-plasty for, 772 Vaginitis bubble bath, 193 female infertility and, 499–500 nonspecific, in children, 196 Vaginoplasty bowel, 764–765 in neovagina creation, 761–765, 762f, 762t, 763f pudendal–thigh flap, 764 with reduction clitoroplasty, 774
Vaginosis, bacterial, 498t, 501 Vanillylmandelic acid, in pheochromocytoma, 322 Variable, 137, 139 Variance, 139 analysis of, 142 Varicella testing, in infertility evaluation, 516 Varicocele, 526, 530, 530f, 798–799 recurrence of, 799 treatment of, 526, 798–799 ultrasonography of, 532, 534f Vas deferens congenital absence of, 525, 526–527, 530, 532 obstruction of, 536, 794 Vascular endothelial growth factor in endometriosis, 733 in implantation, 109, 111 in ovarian hyperstimulation syndrome, 597–598 Vasectomy antisperm antibodies and, 540 reversal of, 794–797, 795f, 796t Vasodilators, 356 Vasoepididymostomy, 794–797, 795f, 796t Vasography, in male infertility, 534, 534f, 793–794, 797 Vasopressin in abnormal uterine bleeding, 307 in hysteroscopic endometrial ablation, 634 in hysteroscopic myomectomy, 631, 632 Vasovagal reaction artificial insemination and, 545–546 hysterosalpingography and, 434 Vasovasostomy, 794, 795f, 796–797, 796t VATER association, 186 Vecchietti procedure, in neovagina creation, 761 Vena cava, inferior, laparoscopy-related injury to, 671–672 Venereal Disease Research Laboratory (VDRL) test, 499 Venous thromboembolism, oral contraceptives and, 392–393, 392t Veralipride, in menopause, 365 Veress needle complications of, 670–671, 673 insertion of, 659–660, 660f, 671 Vesico-uterine pouch, 118, 118f, 123 Virilization, hirsutism and, 267, 268 Viscera, 122–124 Vision disturbances of, clomiphene citrate–ovulation induction and, 553 examination of, in infertility evaluation, 513 Vitamin D deficiency of, osteoporosis and, 373, 376 in menopause, 365 in osteoporosis, 378 Vitrification, for cryopreservation, 594 Von Willebrand’s disease, abnormal uterine bleeding in, 301–302, 303, 304 Vulva melanoma of, 198 psoriasis of, 197 ulcers of, 197 Vulvovaginitis, in adolescent, 195
W Waggle test, for Veress needle placement, 671 WAGR syndrome, 90t, 97 Warfarin, abnormal uterine bleeding and, 302 Warts, genital, 498t, 500 Weight female infertility and, 509 gain of depot medroxyprogesterone acetate and, 400 oral contraceptives and, 395 hirsutism and, 268 in infertility evaluation, 513 loss of, in polycystic ovary syndrome, 225, 283 Wild yam extract, in menopause, 366–367 Williams syndrome, 90t Wilson’s disease, intrauterine device placement and, 412 Wolf-Hirschhorn syndrome, 90t WT1 gene, 96–97, 173 Wunderlich-Herlyn-Werner syndrome, 177
X X chromosome inactivation of, 63, 92 recurrent pregnancy loss and, 610–611 translocations of, 235–236 X-inactive specific transcript, 63 X-linked disorders, 92, 92f. See also Turner’s syndrome primary amenorrhea in, 235t, 236–237 Xenograft, in follicle maturation, 491 XXX syndrome, 88t
Y Y chromosome, 96 azoospermia factor regions of, 98 microdeletions of, 525, 527, 532 Yuzpe regimen, 396–397
Z Zar1, 64 Zinc deficiency, 198 Zoledronic acid, in osteoporosis, 379 Zona pellucida, 55 defects of, 592 sperm interaction with, 105–106 Zona pellucida binding assay, 584 Zp1, 55 Zp2, 55 Zp3, 55 ZP proteins, 105–106 Zygote, 591 Zygote intrafallopian transfer, 567–568
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