Vulvovaginal and common prepubertal gynaecological disorders: Case

This girl has labial adhesions, a common and benign condition in which the labia minora fuse along the midline, in this case almost completely, leaving only a small superior opening. The condition peaks between three months and six years of age and is driven by the hypo-oestrogenic state of the prepubertal vulva, in which the thin vulval epithelium fuses under mild inflammation. The key clinical decision is that the condition is benign and that the management is conservative. [5]

Clinical findings

The key examination finding is the thin, greyish, smooth membrane across the vulva where the labia minora have fused along the midline, which is distinct from the thickened tissue of a congenital obstruction. [5] The small superior opening through which the urine passes explains why the child is asymptomatic, because the urinary stream is not significantly obstructed. The clitoris is visible above the fusion line, which confirms that the adhesion involves the labia minora and not a congenital anomaly of the clitoris or the urethra. [7]

The examination distinguishes the labial adhesion from the congenital conditions that it may superficially resemble. An imperforate hymen or a vaginal atresia presents from birth with a closed introitus and, in the case of an imperforate hymen with menstrual obstruction, a bulging membrane at puberty. The labial adhesion, in contrast, is acquired and develops over months in a child who previously had a normal vulval appearance. [5] The thin, avascular membrane of the adhesion is further distinguished from the thick, vascular tissue of the congenital conditions. [7]

Investigations and diagnosis

The diagnosis is clinical and needs no investigation in the typical case. [5] A urinalysis is performed if the child has had urinary symptoms or recurrent infections, which this child has not. The distinction from an imperforate hymen or vaginal atresia is made on the history and the examination, and no imaging is required. The family is counselled that the adhesion is a benign condition that is common in the prepubertal years and that will almost certainly resolve at puberty when the endogenous oestrogen thins the membrane. [7]

Management and outcome

The management is conservative, reflecting the high rate of spontaneous resolution and the benign natural history. Because this child is asymptomatic with no urinary symptoms, the first approach is observation and reassurance, and the family is counselled that the adhesion will resolve with the endogenous oestrogen of puberty. [7] The family is advised to observe the urinary stream and to return if the child develops dribbling, urinary tract infections, or visible distension of the fused tissue on voiding, which would indicate that the adhesion is causing functional obstruction. [5]

If the adhesion were symptomatic, with urinary obstruction or recurrent infections, the first-line treatment would be a course of topical estrogen cream applied daily to the fusion line for 2 to 6 weeks, which softens the adhesion and allows the labia to separate. [6] Side effects such as mild breast budding or vulval pigmentation are reversible and resolve when the cream is stopped. Manual separation under anaesthesia is reserved for the rare case of urinary obstruction that does not respond to estrogen, and recurrence is common after any form of separation because the underlying hypo-oestrogenic environment persists until puberty. [6]

The long-term outcome for this child is excellent. The adhesion will almost certainly resolve at puberty, and there are no long-term sequelae of the condition once it has resolved. [7] Recurrence is possible before puberty, occurring in up to 20 percent of girls after successful separation, and the family is counselled to expect this and to return for repeat treatment if urinary symptoms recur. The disposition is back to the general paediatrician with a clear plan and the reassurance that the condition is benign and self-limiting. [5]