Nearly one in five sexually active teenage girls in the U.S. say they have been physically abused by a date in the past year, according to a study released Monday.

What’s more, researchers say, these girls are more likely than their female peers to become pregnant or engage in risky sexual behaviors, such as having several partners over a short time span.

Whether the abuse leads to these problems is unclear. But what does seem certain is that much more needs to be done to recognize and prevent teen dating violence, according to the study’s lead author, Dr. Jay G. Silverman of the Harvard School of Public Health in Boston.

“A tremendous number of girls are victimized in dating relationships,” he told Reuters Health, adding that these relationships appear to be a “critical context” in which risky sex practices and pregnancy occur.

For instance, he noted, a previous study found that girls who’d suffered dating violence were often afraid to “negotiate” condom use. In their study, Silverman and his colleagues found that girls who reported physical abuse from a date were less likely than other girls to have used a condom the last time they had sex.

The researchers report the findings in the August issue of the journal Pediatrics.

The results are based on a survey of a nationally representative sample of 6,864 female high school students. Of the 43 percent who said they’d ever had sex, 18 percent reported they’d been hit, slapped or otherwise physically hurt by a boyfriend or girlfriend in the past year. Among girls who said they’d never had sex, about 4 percent reported dating violence.

The 18-percent figure, Silverman said, is “unfortunately” consistent with past research.

Overall, girls who reported dating violence were twice as likely to have had three or more sexual partners in the past three months, and were 50 percent more likely to have started having sex before age 15 or to have used alcohol or drugs the last time they had sex.

Silverman said doctors who provide reproductive health care for teenage girls should explicitly ask them about dating violence and know where to refer them for help if necessary.

Perhaps most importantly, according to the researcher, more work is needed to find out why some boys abuse their girlfriends, and what can be done to keep them from becoming perpetrators in the first place.

Girls in the study did not identify the abuser’s sex, but the authors note that recent research found that only a small percentage of adolescent girls reported same-sex contact, and it’s likely that few of the perpetrators in this study were female.

“The behavior we’re looking to prevent is in boys,” Silverman said, and researchers still need to figure out what types of interventions are effective at this.

Some schools are trying to address the problem of dating violence in their curricula; however, Silverman noted, these efforts are based more on good intentions than on evidence that they work.

SOURCE: Pediatrics, August 2004.