'The Talk'

"You should start talking to children about sex from the day they can talk," said Maureen Lyon, a clinical psychologist at Children's National Medical Center. "Hopefully, when they reach adolescence there's a little bit of groundwork done."

Often, by the time children are teens, they want to talk to parents not so much about how sex works but about how to negotiate relationships, how to listen, how to say no. That's what came out of a recent teen focus group at Children's Hospital about the spread of AIDS, Lyon said.

She suggested parents look for teachable moments, prompted by news stories or life events, to open discussions. Car rides often offer opportunities for tricky conversations, she added.

Kirstin Madaus, a former obstetrics nurse from Falls Church, said her 9-year-old son and 7-year-old daughter always seem to come up with tough questions while she's driving.

"I usually get stuck in the car," Madaus says, chuckling. "They will ask a question, and all of a sudden," she says, the answers just pour out.

Madaus said she relies on her medical knowledge, trying to explain things simply and clearly. She also works not to pass along cultural prejudices. Because she has a close relative who is gay, she's careful to say "when you find someone to love" to her children when talking about lifelong relationships.

The most recent car-ride challenge? Her kids have friends with two mommies and recently asked how the babies got there without sperm.

"I just started talking and talking. Half of my brain is going, 'Shut up, shut up.' "

Talking Doesn't Equal Doing

Don't worry. Talking won't put ideas into children's heads, says Michelle S. Barratt, a professor of pediatrics at the University of Texas Medical School at Houston and a member of the American Academy of Pediatrics Committee on Adolescence.

"There's this myth that if you talk about something it will be on your child's mind when it wasn't before. Most young children could care less," she said.

Parents can use talk about sex to instill their values, ethics and family beliefs, she said, as well as help children understand their own bodies. Barratt puts discussions with her own children in the context of her religious beliefs. Other parents follow a similar tactic.

When Jennifer Rook's 6-year-old son overheard his parents sharing an off-color joke, he latched onto the word "sex" and asked what it meant. The mother of four stalled a bit by getting out her driver's license and showing him "sex: F."

"It's a good word," her son said. He wanted to write it down and show it to his teacher.

Instead Rook, a Mormon who lives in Neola, Utah, gave a scientific explanation of the other meaning of sex, adding, "In our religion we don't believe in doing this until we are married, but there are plenty of people who don't believe the same thing we do."

In talking about sex, experts say it's important that parents cover a range of topics, including emotions and acts of physical intimacy, such as oral sex and anal intercourse.

Charles Wibbelsman, chief of adolescent medicine for Kaiser Permanente in San Francisco, said reports have shown a marked increase in oral sex among young adolescents in the past five years. In a study published last year in the journal Pediatrics, 44 percent of 618 teens in two California public high schools reported having had oral or vaginal sex or both by the spring of 10th grade. Girls were likelier than boys to report feeling bad about themselves and "feeling used."

By ignoring the emotional aspects of sexual behavior, parents put their children at risk, says sex educator Roffman, though many parents think they've done their duty once they've explained the mechanics of intercourse.

"That sets [kids] on the road of thinking about sex in purely mechanical and depersonalized ways," she said.

Choosing not to talk about sex with children also backfires, she said. By third grade, many children from families where such talk isn't encouraged have concluded that their parents aren't the ones to ask about sex, so they ask on the playground.

Through books, education and discussions, she said, parents can work through their own barriers. At the core, she said, most parents want their children to bring similar values to their sexual experiences: privacy, mutuality, respect, responsibility.

"We have controversies about certain value-laden issues, like abortion, but the values that universally parents want children to bring to their sexual experience are all the same, and they are the values that they want children to bring to all relationships. You are teaching your children about life. This is part of life." ·

Elizabeth Agnvall is a frequent contributor to the Health section. Comments:health@washpost.com.