TV'S INFLUENCE TV'S INFLUENCE Chances that a teen will become pregnant or father a child, by age: Age 16

Low level of exposure to TV sex: 5.35%

Medium level of exposure to TV sex: 7.77%

High level of exposure to TV sex: 12.21% Age 17

Low level of exposure: 7.50%

Medium level of exposure: 10.55%

High level of exposure: 15.90% Age 18

Low level of exposure: 7.52%

Medium level of exposure: 10.69%

High level of exposure: 16.32% Source: RAND Corp. YOU CLICKED: WEEK'S MOST POPULAR HEALTH STORIES YOU CLICKED: WEEK'S MOST POPULAR HEALTH STORIES 1: Feds rate U.S. nursing homes 2: Doctors detail first U.S. face transplant 3: Surgeon finds foot in newborn's brain tumor 4: Nursing homes talk new ratings 5: Colonoscopy prep pills carry kidney risk 6: Duggars welcome 18th child No. 7-10: Diabetes drug risks, placebo effect Could the amount of sex teens see on TV predict whether they'll become a teen mother or father? A study in today's Pediatrics says it's a distinct possibility. The study is the first to draw a direct link between sexual content on TV and the likelihood that teens who watch it will become parents. Researchers examined survey data from about 2,000 teens. They plucked out 23 popular shows and asked how much teens watched each. They coded the replies to established indicators of sexual content for each show — everything from nudge-nudge jokes on network sitcoms to full-blown intercourse on steamy cable dramas. BETTER LIFE: Read the blog on sexual health TV AND AGGRESSION: Meanness rubs off on viewers What they found: By age 16, teens who watched a lot of sexually charged TV were more than twice as likely to be pregnant or father an out-of-wedlock baby as teens who watched very little: 12% vs. 5%. The gap holds steady through age 20. Researchers controlled for parents' race, income and education and teens' total TV time. Previous studies have linked sex on TV to earlier initiation of sex; this is the first to link TV sex to pregnancy. "I don't find it surprising," says Jane Brown, who studies media and adolescent health at the University of North Carolina-Chapel Hill. Most teenagers watch about three hours of TV a day, so the likelihood that they'll encounter sexual content is high. "It's a cumulative effect," she says. "It's probably not any one portrayal that makes the difference, but it's a consistent, and now unhealthy, sexual script that adolescents do see as a depiction of appropriate behavior." Psychologist Dave Walsh of the National Institute on Media and the Family sees parents "delegating sex education to Hollywood. … If I'm a 15-year-old kid and no one's really talking to me about sex and I'm watching a lot of sex on TV, it's not a direct, conscious decision — but over time I start to think, 'That's what people do. That's the norm.' " Lead researcher Anita Chandra of the Rand Corp. says even sex talk has an effect. If a child is watching more than just an hour of TV a day, she says, he is getting "a pretty substantial amount of exposure" to sex. Brown says most TV shows portray sex as having few life-altering implications, such as pregnancy or sexually transmitted diseases. She calls it a dearth of the three Cs: commitment, contraceptives and consequences. Even a tame sitcom joke takes a toll, she says. "It says, 'Everybody's thinking about it, everybody's doing it … nobody's suffering any negative consequences.' " READERS: Which shows or channels do you think include the most sex? Do you think viewing sexual situations affects teens? behavior? Has TV ever influenced your attitude or behavior? Share your views below. Guidelines: You share in the USA TODAY community, so please keep your comments smart and civil. Don't attack other readers personally, and keep your language decent. Use the "Report Abuse" button to make a difference. You share in the USA TODAY community, so please keep your comments smart and civil. Don't attack other readers personally, and keep your language decent. Use the "Report Abuse" button to make a difference. Read more