Reproductive performance of women with mu¨ llerian anomalies Beth W. Rackow and Aydin Arici Purpose of review Abbreviations This review discusses current diagnostic techniques for DES diethylstilbestrol mu¨llerian anomalies, reproductive outcome data, and HSG hysterosalpingogram RPL recurrent pregnancy loss management options in reproductive-age women. Recent findings Multiple retrospective studies have investigated ß 2007 Lippincott Williams & Wilkins 1040-872X reproductive outcomes with mu¨llerian anomalies, but few current prospective studies exist. Uterine anomalies are associated with normal and adverse reproductive outcomes Introduction such as recurrent pregnancy loss and preterm delivery, but Congenital anomalies of the female reproductive tract not infertility. Furthermore, unicornuate, didelphic, may involve the uterus, cervix, fallopian tubes, or vagina. bicornuate, septate, arcuate, and diethylstilbestrol-exposed Depending on the specific defect, a woman’s obstetric uteri have their own reproductive implications and and gynecologic health may be adversely affected. associated abnormalities. Common presentations of Uterine anomalies are the most common of the mu¨ llerian mu¨llerian anomalies and current diagnostic techniques are anomalies, but the true incidence is not known since reviewed. Surgical intervention for mu¨llerian anomalies is many women are asymptomatic, and sensitive imaging indicated in women with pelvic pain, endometriosis, modalities have only recently become available [1,2]. obstructive anomalies, recurrent pregnancy loss, and Uterine anomalies are associated with both normal and preterm delivery. Although surgery for most uterine adverse reproductive outcomes; they occur in approxi- anomalies is a major intervention, the uterine septum is mately 3–4% of fertile and infertile women, 5–10% of preferentially managed with a hysteroscopic procedure. women with recurrent early pregnancy loss, and up to Several recent studies and review articles discuss 25% of women with late first or second-trimester preg- management of the septate uterus in asymptomatic women, nancy loss or preterm delivery [3–6]. Overall, uterine infertile women, and women with a history of poor anomalies are associated with difficulty maintaining a reproductive outcomes. Current assessment of pregnancy, and not an impaired ability to conceive reproductive outcomes with uterine anomalies and [1,4]. The proper management of infertile women with management techniques is warranted. uterine anomalies is controversial. Summary Mu¨llerian anomalies, especially uterine anomalies, are Embryology of the female reproductive tract associated with both normal and adverse reproductive Normal development of the female reproductive tract outcomes, and management in infertile women remains requires a complex series of events: mu¨ llerian duct controversial. elongation, fusion, canalization, and septal resorption; failure of any part of this process can result in a congenital Keywords anomaly. Mu¨ llerian development occurs in close associ- congenital uterine anomalies, mu¨llerian anomalies, ation with development of the urinary tract; thus, recurrent pregnancy loss, septate uterus anomalies of the kidney and ureter are commonly identified in females with mu¨llerian anomalies. Gonadal Curr Opin Obstet Gynecol 19:229–237. ß 2007 Lippincott Williams & Wilkins. development occurs as a separate process, beginning by Division of Reproductive Endocrinology and Infertility, Department of Obstetrics, 7 weeks of gestation; therefore, women with mu¨llerian Gynecology, and Reproductive Sciences, Yale University School of Medicine, New Haven, Connecticut, USA anomalies usually have normal ovaries and ovarian hormone production. Correspondence to Beth W. Rackow MD, Department of Obstetrics, Gynecology, and Reproductive Sciences, Yale University School of Medicine, PO Box 208063, New Haven, CT 06520-8063, USA The paired mu¨ llerian (paramesonephric) ducts are ident- Tel: +1 203 764 5866; e-mail: [email protected] ifiable by week 6 of development, and arise from coe- Current Opinion in Obstetrics and Gynecology 2007, 19:229–237 lomic epithelium along the lateral walls of the urogenital ridge. These solid tissue structures elongate caudally, cross the wolffian (mesonephric) ducts medially, and fuse in the midline to form the primitive uterovaginal canal. By week 10, the caudal end of the fused mu¨ llerian ducts connects with the urogenital sinus. Next internal 229 Copyright © Lippincott Williams & Wilkins. Unauthorized reproduction of this article is prohibited. 230 Fertility canalization of the mu¨ llerian ducts occurs, resulting in of one mu¨ llerian duct, fusion of the mu¨ llerian ducts, or two channels divided by a septum. The septum is sub- absorption of the intervening septum between the ducts. sequently resorbed in the caudal to cephalad direction; This is the most common category of mu¨ llerian defect, this is completed by week 20. The fused caudal portion and can result in symmetric or asymmetric and nonob- of the mu¨ llerian ducts becomes the uterus and upper structed or obstructed structures [7]. Depending on the vagina, and the unfused cephalad portion becomes the population studied and the imaging modalities used, fallopian tubes. the most common uterine malformation is the arcuate, septate, or bicornuate uterus [1,3–5]. Vertical fusion The lower vagina has a different embryologic origin. defects result from abnormal fusion of the mu¨ llerian Upon contact between the mu¨ llerian ducts and the ducts with the urogenital sinus, or problems with vaginal urogenital sinus, sinovaginal bulbs originate and prolifer- canalization. These lesions can cause menstrual flow ate toward the caudal end of the uterovaginal canal, obstruction. forming a solid vaginal plate. The lumen of the lower vagina is formed by degeneration of cells at the center The etiology of congenital anomalies of the female of the vaginal plate; this process occurs in a caudal to reproductive tract is poorly understood. Karyotypes are cephalad direction and is complete by week 20. normal (46XX) in 92% of women with mu¨ llerian The hymenal membrane separates the vaginal lumen anomalies, and abnormal in 7.7% of these women [8]. from the urogenital sinus. The central epithelial cells The majority of these developmental abnormalities are of the hymenal membrane usually degenerate prior to infrequent and sporadic, and are thus attributed to poly- birth, and the hymen persists as a thin fold of mucus genic and multifactorial causes [2]. membrane at the introitus. There is no universally accepted standard classification Classification of mu¨ llerian anomalies for congenital anomalies of the female reproductive Congenital anomalies of the female reproductive tract are tract. In 1988 the American Fertility Society (renamed typically classified into three main categories: agenesis the American Society for Reproductive Medicine) and hypoplasia, lateral fusion defects, and vertical fusion created a classification system that focuses on the defects. A fourth group is composed of women exposed to major categories of uterine anomalies (Fig. 1) [9]. diethylstilbestrol (DES) in utero. Agenesis and hypoplasia Documentation of associated anomalies of the vagina, can occur with any or multiple mu¨ llerian structures. cervix, fallopian tubes, and urinary system should be Lateral fusion defects occur due to failure of migration included. Figure 1 American Society for Reproductive Medicine classification system for mu¨ llerian anomalies DES, diethylstilbestrol. Reproduced from [9]. Copyright © Lippincott Williams & Wilkins. Unauthorized reproduction of this article is prohibited. Women with mu¨ llerian anomalies Rackow and Arici 231 Clinical presentation of mu¨ llerian anomalies abnormality requires assessment of the external uterine Although many women with mu¨ llerian anomalies are contour, and this is poorly defined by HSG [26]. The HSG asymptomatic, several gynecologic signs and symptoms correctly diagnoses 55% of septate and bicornuate uteri, are associated with specificanomalies.Womenmay and the addition of ultrasonography improves this result present with cyclic or noncyclic pelvic pain and dysme- to 90% [27]. norrhea suggestive of an obstructive anomaly, retrograde menstruation, and endometriosis [1]. Endometriosis is a Transabdominal, transvaginal, or transperineal ultrasono- common finding in women with obstructive and non- graphy effectively evaluates the internal and external obstructive mu¨ llerian anomalies, and may be a cause uterine contour, detects a pelvic mass, hematometra or of infertility [10,11]. Primary amenorrhea with hematocolpos, confirms the presence of ovaries, and pelvic, vaginal, or back pain or a pelvic mass is con- assesses the kidneys. Timing the study to the secretory cerning for a transverse vaginal septum or an imperfo- phase of the menstrual cycle provides better visualization rate hymen. Mu¨ llerian agenesis (congenital absence of of the endometrium and thus the internal uterine contour the uterus and vagina) presents with amenorrhea. [28]. Sonohysterography can further delineate the intra- Abnormal uterine bleeding may occur with a septate cavitary space, and internal and external uterine contours uterus, a partial or microperforate obstruction, or a [29]. When available, three-dimensional ultrasonography longitudinal septum when only one tampon is used is a highly accurate imaging modality that provides (two are required). thorough views of the pelvic anatomy and detailed visual- ization