Appearance of the Hymen at Birth and One Year of Age: A Longitudinal Study

Abstract

The increase in the number of prepubertal girls who require evaluation of possible sexual abuse creates a need for detailed information, not previously available from cross-sectional studies, on the influence of aging on the hymen's appearance. This study was undertaken to evaluate and document, using a longitudinal design, changes in the hymen's morphology in 62 girls without a history of sexual abuse between birth and their first birthday. Labial agglutination extensive enough to obscure the inferior half of the hymen was observed in 5 girls (8%) at 1 year of age. Thirty-three (58%) of the remaining 57 infants experienced a marked decrease in the amount of their hymenal tissue between birth and 1 year. Significantly more infants at 1 year of age had a crescentic configuration (0% vs 28%), and significantly fewer had an external ridge (82% vs 14%) as compared to the newborn period. An annular hymen with a central or ventrally displaced opening progressed to a crescentic hymen in 13 children by 1 year, 77% (10/13) of whom were observed to have a notch (cleft) at the 12 o'clock position on the earlier study. A superior notch appeared for the first time in 9 girls. Lateral notches resolved in 5 cases and persisted in 2. Inferior notches between the 4 and 8 o'clock positions were not observed at birth or 1 year. Hymenal tags resolved in 2 instances, persisted in the same location in 2, and appeared for the first time in 4 cases. Three girls had a hymenal mound (bump) at 1 year, all of which could be traced back to a similar finding at birth. No change in the number of infants with longitudinal intravaginal ridges was observed. Clinicians should be aware of the influence of age and changing estrogen levels on the hymen's morphology in order to differentiate normal anatomical from posttraumatic or infectious changes.