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]