Vaginal introital diameter in the evaluation of sexual abuse

Physical objective markers to aid in the diagnosis of sexual abuse are few. We therefore studied 242 females, ages 1 through 12 years, to determine if the vaginal introital diameter is useful in evaluating a child for sexual abuse. The children were divided into three groups: Group I, history of sexual contact and/or Neisseria gonorrhoeae; Group II, no history of sexual contact but at risk; and Group III, nonabused. A vaginal introital transverse diameter of greater than 4 mm was more prevalent among children in Group I (94%) than in Group II, (5%); or in Group III (0%) (chi 2, p less than .001). Eighty-eight percent of children who complained of penile-vaginal penetration had a vaginal introital diameter greater than 4 mm as compared to 18% of children with no penetration (chi 2, p less than .001). Forty-six percent of children who complained of fondling with penetration had a vaginal introital diameter of greater than 4 mm as compared to 14% in those without a history of penetration (chi 2, p less than .008). Fifty-eight percent of children with more than one encounter had a vaginal introital diameter greater than 4 mm as compared to 29% in those with one encounter (chi 2, p less than .006). In a logarithmic regression analysis, the greatest proportion of children with a vaginal introital diameter greater than 4 mm was observed in the penile-vaginal contact group (chi 2, p less than .00003). The test is not very sensitive but highly specific. The sensitivity drops precipitously at greater than 5 mm without losing the specificity. A vaginal introital diameter of greater than 4 mm is highly associated with sexual contact in children less than 13 years of age.