Teens — particularly girls — with strong religious views are less likely to have sex than are less religious teens, largely because their religious views lead them to view the consequences of having sex negatively. According to a recent analysis of the NICHD-funded Add Health Survey, religion reduces the likelihood of adolescents engaging in early sex by shaping their attitudes and beliefs about sexual activity.

The study also found that parents' religious beliefs and attitudes toward sex did not directly influence teens' decisions to have sex. Rather, parents' attitudes toward sex seemed to influence their teens' own attitudes toward sex, and indirectly, their teens' behavior.

When teens do have sex, their beliefs about the consequences of sexual activity become more permissive — meaning more positive or favorable — but their religious views do not change. In particular, adolescent girls who had sex reported that they were more positive about having sex in the future. However, the greatest predictor of whether teens would have sex — regardless of their religious views or attitudes — was whether or not they were dating.

Sexual intercourse places teens at risk for sexually transmitted diseases, including HIV, and unintended pregnancy. The information provided by the study may prove important for health researchers and planners devising programs that help prevent teens from engaging in sexual activity.

"A better understanding of why religious adolescents are less likely to engage in early sexual intercourse may help in designing prevention programs for this behavior," said Duane Alexander, M.D., Director of the NICHD.