O HYMEN! O hymenee!
Why do you tantalize me thus?
O why sting me for a swift moment only?
Why can you not continue DRIPPING PITCH? O why do you now cease AND MADE OF WOOD?
Is it because, if you continued beyond the swift moment, you would soon certainly kill me LIKE YOU KILLED MY BABY WHO HAS ANIMALS LIVING IN HIM?

Imperforate hymen is at the extreme of a spectrum of variations in hymenal configuration. Variations in the embryologic development of the hymen are common and result in fenestrations, septa, bands, microperforations, anterior displacement, and differences in rigidity and/or elasticity of the hymenal tissue. Inspection of the external genitalia and anus are important components of the physical examination of the female neonate. While this examination can and should be accomplished by the pediatrician, the observant delivering obstetrician can learn much about the normal variations in genital configuration by examining the female neonate in the delivery room, keeping in mind the influence and structural changes induced by maternal estrogens. Under this influence, the labia majora are plump, the hymen is elastic and often lax and fimbriated, and the mucosal surfaces (ie, introitus, fossa navicularis) are pale pink.

Problem: In spite of the recommendations for early inspection of the external genitalia, variations in hymenal anatomy typically escape diagnosis until the time of menarche. Different normal variants in hymenal configuration are described, varying from the common annular, to crescentic, to navicular (with an anteriorly displaced hymenal orifice). Rarely, hymenal variations may be clinically significant before menarche. In the case of a navicular configuration, urinary complaints (eg, dribbling, retention, urinary tract infections [UTIs]) may result. Sometimes, a cribriform or navicular configuration to the hymen can be associated with retention of vaginal secretions and prolongation of the common condition of a mixed bacterial vulvovaginitis.

Imperforate hymen in infancy or childhood

An infant or child may be thought to have an imperforate hymen. Careful examination with pressure applied to the fourchette may reveal a microperforation, sometimes with an anteriorly placed opening just beneath the urethra. Capraro described a surgical technique similar to a perineotomy to correct such a defect; however, in the asymptomatic patient, waiting until puberty is suggested before deciding whether such a technique is necessary. The hymenal changes that result from estrogenization (increased elasticity and fimbriation) may preclude the need for surgery.

Sexual abuse

Accurate description of the morphology and integrity of the hymen is critical in the diagnosis of female sexual abuse. Concerns about hymenal disruption and lacerations associated with sexual abuse with digital or penile penetration have led to discussions of the normal hymenal diameter. At one time, the diameter of the hymenal opening (measured within the hymenal ring) was proposed to be approximately 1 mm for each year of age. Clearly, this guideline does not apply in the neonatal stage, when maternal estrogens lead to an elastic hymen; however, in the prepubertal stage, marked enlargement, according to this guideline, should prompt consideration of the possibility of abuse. An important difficulty with this “rule of thumb” is that the degree of the child’s relaxation and comfort with both the examination and the examiner clearly affects measurements, as does the type of measuring device used.

Experts in sexual abuse assessment have used unaided visual examination and colposcopy to examine the integrity of the hymenal ring. Lacerations through the hymen into the fossa navicularis and introitus suggest a penetrating injury. Frequently, sexual abuse evaluations are conducted at some time remote from the immediate injury; thus, healed or healing lacerations are noted.

Muram concluded that the use of the colposcope by an experienced examiner adds little to the evaluation. In addition, Muram proposed a scale that the examiner can use to evaluate physical findings as normal, abnormal and nonspecific, abnormal and suggestive of abuse, and definitive for abuse. The latter category includes only the situation in which sperm are found on examination.

Anatomic anomalies

Consider anatomic anomalies that can be confused with imperforate hymen in the differential diagnosis. These anomalies include the following:

<LI>Acquired labial adhesions

<LI>Obstructing or partially obstructing vaginal septa (longitudinal or transverse)

<LI>Vaginal cyst

<LI>Vaginal agenesis (Mayer-Rokitansky-Kuster-Hauser syndrome) with or without the presence of a uterus or functional endometrium

<LI>Androgen insensitivity (testicular feminization)

Frequency: Imperforate hymen probably is the most frequent obstructive anomaly of the female genital tract, but estimates of its frequency vary from 1 case per 1000 population to 1 case per 10,000 population. McCann et al (1990) examined 93 girls, aged 10 months to 10 years, to collect normative data on genital anatomy in nonabused prepubertal girls and found 1 child with an imperforate hymen (1.2%) and 2 children with hymenal septa (2.5%).

Etiology: Imperforate hymen and related genital tract anomalies result from abnormal or incomplete embryologic development.

Pathophysiology: The genital tract develops during embryogenesis, from 3 weeks’ gestation to the second trimester. The initial development of both the male and female genital tracts occurs concurrently and is referred to as the indifferent stage of development.

<LI>Paired wolffian (mesonephric) ducts connect the mesonephric kidney to the cloaca. The metanephric or true kidney derives from the ureteric bud (arising from the mesonephric duct) at about the fifth embryonic week.

<LI>The paramesonephric or müllerian ducts can be identified during the sixth week of embryologic development and lie lateral to the wolffian ducts until they reach the caudal end of the mesonephros, where they come toward the midline.

<LI>During the seventh week, the urorectal septum forms to separate the rectum from the urogenital sinus.

<LI>By the ninth week, the müllerian ducts move caudally to reach the urogenital sinus, forming the uterovaginal canal and inserting into the urogenital sinus.

By the 12th week, the paired müllerian ducts have fused into a single tube (ie, primitive uterovaginal canal). Two solid evaginations form from the distal aspects of the müllerian tubercle from the sinovaginal bulbs (of urogenital sinus origin) or vaginal plate. The initial or cephalad portion of the müllerian ducts forms the fimbria and fallopian tubes; the more distal segment forms the uterus and upper vagina. The canalization of the paramesonephric ducts and/or upper vagina joins with the vaginal plate, which canalizes beginning caudally and creates the lower vagina. By the fifth month of gestation, the canalization of the vagina is complete. The hymen itself is formed from the proliferation of the sinovaginal bulbs, becoming perforate before birth.

Gonadal development

The development of the gonads occurs from the migration of primordial germ cells to the genital ridge, while the genital tract itself develops from the müllerian ducts (paramesonephric ducts), urogenital sinus, and vaginal plate. Thus, anomalies of the vagina, hymen, and uterus are not accompanied by abnormalities of ovarian development, and hormonal and endocrinologic function is without abnormality, leading to expected pubertal breast development.

Because the mesodermal layer contributes to the development of the kidneys, gonads, and ductal structures, defects or insults in embryologic development may result in congenital defects of the kidneys that accompany abnormalities of the vagina and uterus.

The lining of the urethra and urinary bladder derives from endoderm, and the urogenital sinus forms the urethra and vestibule in females. The ectoderm fuses with the endoderm to contribute to the patency and canalization of the genital tract. Defects in this process lead to fusion failures and imperforate and obstruction defects.

Familial occurrence

Familial occurrence is reported, and screening by history or examination of family members is warranted. Dominant transmission (either sex-linked or autosomal) and sibships suggesting a recessive mode of inheritance are described. The inheritance of müllerian defects likely is polygenic or multifactorial, although some syndromes of heritable disorders are described with associated genital and nongenital anomalies.

Anomalies of the female reproductive tract

Anomalies of the female reproductive tract can result from agenesis or hypoplasia, vertical fusion and/or canalization defects, lateral fusion and/or duplication abnormalities, or failure of resorption, resulting in septa.

Clinical:

Diagnosis in infancy or childhood

The diagnosis is sometimes made in infancy. The patient presents with a bulging yellow-gray mass at or beyond the introitus. The presence of an abdominal mass has been described in association with urinary obstruction.

Diagnosis has been made in utero with obstetrical ultrasonography. Ultrasonography is an essential first step in diagnosis, precluding unwise and unplanned surgical intervention with resultant injury to the urethra.

Diagnosis and surgical repair in puberty and menarche

Observation with a planned hymenotomy during puberty is a reasonable course of action in most cases, assuming no urinary symptoms or obstruction is present. More typically, a mucocele is not present. If a patient is diagnosed with an asymptomatic imperforate hymen in infancy or childhood, the optimal time for surgical repair is during puberty and prior to menarche. During this time, surgical repair prevents the typical situation in which a young woman presents with intermittent abdominal pelvic pain, which can become severe over the course of several months.

Urinary pressure and even retention with dilation of upper urinary tracts from obstruction is not uncommon. Frequently, vaginal and rectal pressure is present. Severe constipation and low-back pain are described as presenting symptoms. The laborlike menstrual cramps may be severe and cyclic, although the cyclic nature of the symptoms may not be apparent easily or immediately to the young woman or her family.

Unfortunately, the typical findings at diagnosis include a large collection of blood within the uterus (hematometra) and an even larger collection of blood within the distensible vagina (hematocolpos). Additional findings may include blood-filled fallopian tubes (hematosalpinges) and signs of retrograde menses, occasionally to the point of the development of intra-abdominal endometriosis and severe adhesions. The classic teaching is that endometriosis associated with obstructive anomalies resolves spontaneously and does not cause problems with subsequent pain and infertility compared to endometriosis arising spontaneously; however, this assertion is anecdotal rather than evidence based.

Differential diagnosis

The differential diagnosis of an imperforate hymen includes many conditions, some rare and others relatively common.

Labial adhesions

The presence of acquired labial adhesions in a prepubertal girl is a common situation that often is confused with absence of the vagina. Labial adhesions are not congenital and result from agglutination due to inflammation. Small areas of labial adhesions can be managed expectantly. Extensive labial adhesions or those associated with such symptoms as recurrent UTIs, urinary dribbling, or recurrent vulvovaginitis can be managed easily using the topical application of estrogen cream for 2-6 weeks. Such treatment results in the marked thinning of the adhesions, often with spontaneous resolution. Adhesions that do not resolve completely over this interval but are thin and translucent almost always can be managed in the physician’s office with gentle manual separation, after the application of topical lidocaine jelly or prilocaine (eutectic mixture of local anesthetics [EMLA]) cream.

Separation of thick adhesions is possible to accomplish in the office with a child who can be restrained; however, this procedure ultimately is counterproductive because the examination frequently is difficult. General anesthesia in an operative setting may be required.

The biggest problem in managing labial adhesions is that recurrent adhesions are common because the epithelial surfaces are damaged during separation. Parents or caretakers must be instructed on how to ensure that the child maintains excellent perineal hygiene and avoids vulvovaginitis. The application of a topical emollient on a daily basis helps to prevent recurrences until the endogenous pubertal estrogen stimulation alleviates the risk.

Labial adhesions may be confused with posterior labial fusion encountered in congenital adrenal hyperplasia and may be differentiated by careful physical examination with attention to the presence or absence of clitoromegaly.

Hymenal obstruction

In the case of incomplete hymenal obstruction due to a cribriform hymen or hymenal band, the typical presenting complaint is difficulty inserting a tampon. Anatomic variations must be distinguished from the involuntary vaginismus or contraction of the perineal musculature or levator ani muscles, which can be associated with the learning process of tampon insertion, becoming a vicious cycle when persistent insertion is attempted without success and causing pain.

Hymenotomy occasionally may be indicated in the case of a rigid inelastic hymen, particularly for young women who are athletes (eg, swimmers, divers, gymnasts, cheerleaders). A reasonable alternative to surgical correction involves the use of progressive self-digital dilation in a motivated young woman. In athletes with a rigid hymen, an evaluation for possible hypoestrogenism associated with vigorous physical activity should be considered; if present, estrogen replacement improves the hymenal characteristics and increases hymenal elasticity.

Hymenal bands

This condition typically is amenable to division using a local anesthetic in the office; however, the young woman’s age and tolerance of such an office procedure must be predicted and judged. Her degree of motivation for tampon use or intercourse impacts the timing at which she requests such a procedure. A typical presenting history of an individual with a hymenal band is the ability to insert a tampon but extreme difficulty in removing it (eg, patient in whom the tampon string became wrapped around the hymenal band, leading to marked edema and pain when removal was attempted).

Obstructing longitudinal or transverse septa

These conditions require careful preoperative evaluation to define the anatomy. The repair of such complicated anomalies usually should be left to gynecologists at a tertiary care center where these cases are not a rarity. MRI usually is the criterion standard for defining the anatomy.

Vaginal agenesis or androgen insensitivity

The evaluation and management of vaginal agenesis or androgen insensitivity syndrome is beyond the scope of this article, but these conditions should be considered in the differential diagnosis. These patients should be referred to a gynecologist who specializes in adolescents. The options for creation of a neovagina are operative, such as a McIndoe procedure with the creation of a neovagina, or nonoperative, using progressively larger Lucite dilators.