The magazines' survey says 78 percent of mothers think their daughters feel comfortable talking to them about sex—but only 39 percent of daughters actually do.

When it comes to teenagers, Dr. Berman urges all parents to stay calm when approached for information. Overreacting, she says, could make your child hesitant to come to you in the future. "Listen—don't just lecture them," Dr. Berman says. "[Encourage them] to ask questions about the words and the terms and the things they're hearing about at school, to ask questions about what they're seeing in the media."