Let’s face facts. At some point your child is going to have sex—and it may well be before you think she or he is ready. Some 13 percent of girls and 15 percent of boys are no longer virgins by the age of 15. By 17 about 40 percent of teens have had sex.

Your concern is well placed. Younger adolescents may not be ready for the emotional complexities of sexual relationships. And more than a quarter of younger teens who have sex don’t protect themselves against pregnancy and sexually transmitted diseases. You probably knew that open communication about sex helps teens wait. Talking to your kids early and often about your values is key. That hasn’t changed, but two newer studies offer unexpected specifics about what else you can do to slow teenagers down.

Young women who have close bonds with their fathers are only about half as likely to have sex with their boyfriends as girls who have poor rapport with their dads, according to research from the University of Texas at Austin. “Girls who have high-quality relationships with their fathers, who feel that their fathers enjoy spending time with them, tend to be more self-confident,” explains study author Mark Regnerus, Ph.D., assistant professor of sociology, and author of Forbidden Fruit: Sex and Religion in the Lives of American Teenagers. “They’re less likely to base their self-worth on the opinions of male peers, because they already feel valued by their dads.” Dr. Regnerus reminds us that it’s important for fathers to stay involved with their daughters—even when it’s not clear if they’re welcome. “Dads shouldn’t just be pushovers,” he says. “But discipline is most effective when it’s clear that the father loves his daughter too.”

Close-knit communities, in which neighbors feel able to intervene if they see others’ kids misbehaving, also deter teens from early sex. A study of 80 Chicago neighborhoods found that children who grew up in such cohesive areas tended to have sex later than other kids, regardless of income level. When teens know that they’re watched over by a whole network of adults, they behave with more restraint, says study coauthor Jeanne Brooks-Gunn, Ph.D., professor of child development at Columbia University, in New York City. “When there’s a sense of shared responsibility, if your teen swears at a storekeeper, you know about it before he gets home,” she says. To achieve this atmosphere, engage with your neighbors, whether through religious or civic organizations, sports or other social activities that bring you together.

Both studies support previous research that has found that however dismissive teens seem, they do look to parents for guidance. “Foolishly, parents think they become irrelevant as kids get older,” says Dr. Regnerus. “But the most important thing is to remain involved in your teens’ lives”