The O/Seventeen Sex Survey

So it's true that you need power tools to get through to the teenage brain—or at least it seems that way when you learn that only 4 percent of girls say their moms are the biggest influence on their attitudes toward sex. Actually, though, Terri Apter argues, one shouldn't take that 4 percent at face value. "Teens are so intent on developing this very exciting new self they feel emerging, it's almost with a kind of pride that they won't acknowledge the effect their mother has," she says. "Only later will they look back and see how their parents influenced them." And indeed, when asked another way—"How has talking to your mother affected your decisions about sex?" 60 percent of the girls said it had influenced them. "But," adds Apter, whose position at the University of Cambridge is the British equivalent of an American academic dean, "there's a truth here: It is very difficult to counteract the influences of peers and culture. So a lot of the sex talk challenge for a mother is asking, 'How can I increase my impact?'"

Melissa Milem, 27, a paralegal from Amesbury, Massachusetts, doesn't even know where to start. Whenever she goes near the topic of birds and bees, or boys, her daughter refuses to talk; nor have suggestions of seeing a counselor or communicating through letters helped. "Alyssa is 14. She's a freshman and she's beautiful, and her past three boyfriends have been 16 and 17," says Melissa, who has a 4-year-old daughter as well. "I'm pretty sure Alyssa has had sex. But when I try to talk to her about it, she wants no part of it. If we do talk about it, she'll say, 'How many times do I have to tell you, I'm not having sex with him?' I usually end up very frustrated because I want her to realize that life isn't all about boys. I want her to be a kid, find girlfriends, have fun—and I don't know how to get that into her head. We end up yelling at each other."

"We fight a lot," Alyssa agrees. "If she let me have more leeway to do the things I want to do, maybe I would have a better relationship with her and tell her more about what's going on in my life."

But Melissa doesn't dare. She can remember more vividly than most mothers what it's like to be 14, having got pregnant with Alyssa by her first boyfriend at age 12—an uneasy number to live with but one she handles gracefully. Now she struggles to keep her teenager—"still my baby"—from following in her footsteps.

"One day I came home early from work because I was sick, and caught Alyssa's boyfriend in the house after school. I broke down in tears. I said, 'I don't understand why you don't get this. It's not safe; you can't do this. You have to help me out here.' And she shut down. She was like, 'Eh, I'm not talking.' She went to her room."

In a situation like Melissa's, Apter says, trying to get control is probably futile. Instead, Apter suggests easing off ("Okay, you don't want to talk about it; I'll step back") but being honest ("I feel nervous, though; is there some conversation that you are comfortable with?"). Even just chatting about a romance—the daughter's or other people's—can be helpful. "At least if you're talking about how important it is to be treated with respect, to have a say in the relationship—that sort of thing seems to prevent unwanted pregnancy," Apter says.

But this is particularly difficult emotional terrain. Urging your daughter not to repeat your mistake—especially when that mistake resulted in her birth—is inevitably a mixed message. "There's a deep identification, daughter to mother. And the mother wants to be a role model," says Apter. Essentially, however, she's telling her girl: Do as I say, not as I do. And that's a tough message to take in. "She doesn't trust me," Alyssa says. "She thinks I'm going to make the same mistake she did. And she doesn't understand how I want to be my own person."

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