Information and Resources

Young Girls, Older Boyfriends & Sex

Sex by 9th Grade

In the ninth-grade survey, students were asked, "Have you had sex in the last 12 months?" defining sex as a "man's penis in woman's vagina."

Most students answered "no" to that question. But those who had had a serious relationship by seventh grade were more likely to report having sex in the year leading up to the survey.

"One in 10 males and females who reported no relationship in seventh grade said that they had had sex in the 12 months before the ninth-grade interview, compared with at least one in five who reported in seventh grade having had a same-age or older girlfriend or boyfriend," write Marin and colleagues.

The survey didn't ask students to identify their sexual partner or that partner's age. So the researchers don't know exactly when, or with whom, students started having sex.

Boys, Girls & Age

Among boys, those with a serious girlfriend by seventh grade were twice as likely to have had sex in the year before the ninth-grade survey -- compared with the girls, who were three times as likely.

And while girls with a serious older boyfriend by seventh grade were twice as likely to have had sex as those who'd had a same-age boyfriend, no such pattern was seen between boys and older girlfriends. However, those couples were rare, which might make it hard to spot trends in that group.

Physical & Emotional Maturity

Girls who hit puberty early (menstrual periods by sixth grade) were more likely to have an older boyfriend by seventh grade.

"This finding is of concern because young females are experiencing menarche (the start of menstrual periods) at increasingly early ages," the researchers write.

They add that since physical maturity doesn't always come with emotional maturity, girls who start puberty early may need advice about handling sexual attention, especially from older boys.