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 and child.
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 fimbriated, and the mucosal surfaces (ie, introitus, fossa navicularis, vaginal vestibule) are pale pink.