To evaluate the prevalence of sexual abuse in the pediatric population of the Federal District and discuss the difficulties in interpreting the examination of the genitalia in this age group, both by general practitioners as medical expert forensic officers.This is a retrospective, transversal, and epidemiological study on children younger than 12 years, who attended the Institute of Forensic Medicine of DF (IML-DF), Brasilia, Brazil, with suspicion of sexual abuse between 2008 and 2009.During this period, 3607 persons with suspected sexual abuse and 1762 (48.8%) children younger than 12 years were treated in IML-DF. Of this total, 238 (13.5%) were boys, and 1524 (86.5%) were girls. Among the boys, the average age was 6.5 years, and 9.6% were found to have injuries consistent with sexual abuse. In 43.4% of these cases, the perpetrator was known. The main lesions found were anal fissures and lacerations, bruises, and anal dilatation. In 20 cases (8.4%), the time interval between fact and examination precluded any conclusion. The girls (1524 cases) referred to the IML-DF were subjected to two types of tests: libidinous acts (773 to 50.7%) and rape (751 to 49.3%). In tests of libidinous acts, 5.3% had signs of sexual abuse perpetrated by acquaintances (68.2%), and 3.0% were inconclusive because of the long time lag between the examination and fact. In survey of rape cases, only 2.1% of subjects examined had lesions consistent with abuse. In 57 of 1524 cases, specimens were sampled for sperm test, and five cases (8.7%) showed positive results. The average age of girls being sexually abused (10.7 years) was higher than that for boys (6.5 years).Our findings confirm the discrepancy between the expectations of parents and the general practitioner, and the reality of the findings in specialized centers. Approximately 90% of child victims of abuse do not show evidence of physical damage. These were found in less than 10% of abused children. Physical signs of abuse often are difficult to recognize and should not be the only indicators.