Your 14-year-old daughter is curled up on the couch, absorbed in a rerun of "Sex and the City." She watches with interest as Samantha Jones, the show's lusty femme fatale, has lunch with a man she's just met. After dessert, Samantha and the guy make a dessert of each other at his plush Manhattan apartment.

An hour later, Samantha is back on the street, no more affected by this sexual encounter than by a walk in the park. She's already forgetting the guy.

You're a little nervous as you watch your daughter track Samantha's adventures. You know that she sees a lot of stuff like this on TV, and you catch yourself wondering -- is there a chance that Samantha's attitude will rub off on her?

You dismiss the thought quickly. After all, as a mom, you're doing just what the child-rearing experts advise: You keep the channels of communication open, and you've explained the difference between responsible sexual behavior and the "Sex and the City" gals' free-wheeling ways. Besides, your daughter gets sex education at school, and she's learned about the risks of casual, unprotected encounters.

In the end, you conclude, shows like "Sex and the City" are just harmless entertainment -- a chance for teens to unwind and to giggle about a make-believe world.

Think again, warns a new study. If your teen logs lots of hours watching sexually suggestive TV shows, you have good reason to worry.

The study, from the Rand Corp., found that young people who are exposed to lots of sexual situations and dialogue on TV are twice as likely to get pregnant -- or to be responsible for a pregnancy -- as those who watch little. The link with pregnancy remained even after controlling for factors such as delinquent behavior and living in a single-parent household.

The Rand study is apparently the first to document the connection between sexed-up TV and teen pregnancy. But it's consistent with other research, which has found links between watching these shows and early onset of sexual activity, and also between watching sex-charged music videos and getting a sexually transmitted disease.

Sorry, Mom and Dad. We can stuff our daughters' purses with condoms, but we can't expect that to protect them from the heartbreak teen sex can bring. If we want to help our kids successfully negotiate the pitfalls of adolescent life, we have to say "no" to sex-drenched TV and movies, even when their response is, "You're the meanest mom in the world!"

We don't need fancy studies to explain why.

Common sense tells us that school isn't the only place our kids learn lessons. The popular culture is often a more powerful teacher. The images and messages young people encounter there can mold their understanding of how the world works, what is important in life and what society expects of them.

I ran across a book when my kids were small that summed up why it's so important to monitor young people's encounters with the popular culture. "Nothing is more important in the growth of the child than the direction of his admirations," it said. "All children are imitative, and they tend to imitate what impresses them."

In this respect, the glamour queens of "Sex and the City" and similar shows are alluring icons. They appear confident, sophisticated and fulfilled, and guys drool when they pass. The fundamental lesson they teach our kids is that to look and act "hot" should be a human being's highest aspiration.

Many teen girls fall for this message. They are hungry for meaning, lacking in confidence, yearning to be popular and dying for male attention. Is it surprising that they see Samantha Jones, Carrie Bradshaw and their ilk as women to emulate?

It's tough being the parent of a teenage girl today. Our "Sex and the City" culture is everywhere around her, trying to grab her attention and convince her that no-holds-barred sexual exploration is a key to her happiness.

A parent who intervenes between this culture and a daughter can expect tears and heartache. But both the Rand study and common sense tell us those tears may be a worthy investment in preventing a truly profound heartache down the road.

Katherine Kersten • 612-673-1774

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