NEW YORK (Reuters Health) - It's news that may make sex abuse investigators' jobs even more difficult: Girls who describe repetitive sexual abuse by genital penetration rarely have definitive physical evidence to prove it, according to a report in the journal Pediatrics.
Dr. Jim Anderst at the Children's Mercy Hospitals and Clinics in Kansas City, Missouri, and colleagues worked at a child advocacy center with 506 girls between the ages of 5 and 17 who reported penile-genital abuse. In all cases, the abuse had occurred at least 72 hours before the girls came to the center.
Anderst and his colleagues classified abuse as "penetrating" as long as the child believed that "the perpetrator's penis went 'inside' her genitals."
Any of the following was considered "definitive evidence": a healed "transection" (or tear) in the hymen, a hymen with a missing segment, or signs of genital trauma such as bleeding, cuts or bruises.
For purposes of the study, the researchers did not have access to the patients' case histories. Instead, they relied solely on the children's reports and on what could be observed during genital examinations.
Relying on the victim's report is the standard way to evaluate sexual abuse, the researchers note, adding that it's rare for children to fabricate such stories.
In fact, according to the authors, in an earlier study of child victims of sexual abuse, 60 percent of the children actually under-reported the frequency or severity of the sexual acts, and none over-reported it.
Only 56 of the girls (10 percent) had "definitive" evidence, which in all instances were healed hymen tears in girls who were 10 years old or older.
The number of penile-genital penetrations the girls reported had no effect on the likelihood of physical evidence, the researchers said. In fact, the investigators could find no definitive evidence in 87% of children who said they'd been penetrated more than 10 times.
Children under age 10 were twice as likely to report more than 10 penetrations, but none had any physical proof.
"Similar results were seen for victims of repetitive assaults involving perceived penetrations over long periods of time, as well as victims with a history of consensual sex," said the authors.
Among the possible explanations for their findings, according to the researchers:
--Injuries might have occurred and healed.
--Penetration might have occurred without injury.
--Some children might have interpreted or described nonpenetrative genital-genital contact as actual penetration.
While the stories behind each child's report of abuse were not part of the study, the researchers do describe one case as an example: a 12-year-old girl who was abused 209 times by her adult stepbrother over the course of more than a year. She recorded each event in her diary, in great detail, including her pain and bleeding and a time when her abuser's condom came off in her vagina. Even in this child, there was no "definitive evidence" of vaginal penetration.
In the case of the 12-year-old girl, the authors said, she finally reported the abuse because "he could do it to someone else."
SOURCE: Pediatrics, September 2009.