(CNN) -- Sexual content on television is strongly associated with teen pregnancy, a new study from the RAND Corporation shows.

New information linking sexual content on television with teen pregnancy will help develop prevention programs.

Researchers at the nonprofit organization found that adolescents with a high level of exposure to television shows with sexual content are twice as likely to get pregnant or impregnate someone as those who saw fewer programs of this kind over a period of three years. It is the first study to demonstrate this association, RAND said.

A central message from the study is that there needs to be more dialogue about sex in the media, particularly among parents and their children, said Anita Chandra, the study's lead author and a behavioral scientist at RAND.

"We know that parents are busy, but sitting down and watching shows together with their teen, talking about the character portrayals, talking about what they just witnessed, and really using it as a teachable moment is really, I think, a good recommendation from this research," Chandra said.

To measure exposure, the researchers used a method developed by another research group evaluating 23 shows for sexual content. Then, they asked teenagers how frequently they watched each of those shows, and developed a score based on exposure to the shows.

"We know that if a child is watching more than an hour of TV a day, we know there's a sexual scene in [the] content every 10 minutes, then they're getting a fair amount of sexual content," Chandra said.

Melody Monroe of Norfolk, Virginia, who had her first child when she was 17, said she agrees that sex on television contributes to teen pregnancy. Monroe, who shared some of her views on iReport.com, recalls watching shows on Lifetime Television with her mother that were "almost soft porn," with kissing and bedroom scenes.

"Oh, the guy gets the girl, they fall in love, happily ever after, babies come, I thought that was one way of being loved," said Monroe, now 26. "Happily ever after doesn't happen." iReport.com: Were you a teenage parent? Share your story

But Sandy Tomlinson of Glendale, Arizona, who had her son at age 15, said she doesn't think television affects teen pregnancy -- rather, teen pregnancy has to do with the way parents raise their children.

"I feel that if my parents would have been more involved in my life that I would have made different choices," said Tomlinson, now 27, who also shared her story with iReport.com. "It gets old hearing all these studies that blame everything and everybody but the parents."

The RAND study, published in the November edition of the journal Pediatrics, looked at the results of three surveys of about 2,000 adolescents ages 12 to 17 from 2001 to 2004. It focused on the results from more than 700 participants nationwide who had engaged in sexual intercourse by the third survey.

Researchers asked adolescents about a mix of sitcoms, dramas, animated shows and reality shows known to have sexual content. Chandra declined to name any specific programs, but said sexual content is "pretty pervasive."

While this is one of many factors that influence teen pregnancy, the study is compelling, given that adolescents spend a significant amount of time watching television, Chandra said. The information will help develop prevention programs for kids that focus on media literacy, she said.

Even when accounting for other related factors such as demographics and risk-taking behaviors, the correlation between televised sexual content and teen pregnancy persisted, she said.

The study also found that adolescents living in a two-parent household had a lower probability of pregnancy.

African-Americans, girls, and adolescents with behavioral problems had a higher likelihood of getting pregnant or impregnating someone, as did youths who intend to have children early, the study showed.

A strong association between sexual content on television and teen pregnancy is not surprising, said Dr. Yolanda Wimberly, an assistant professor of clinical pediatrics at the Morehouse School of Medicine and the medical director for the Center for Excellence in Sexual Health. Wimberly, who works in an adolescent clinic, was not involved in the study.

"You cannot expect to have a sexually saturated society with all of your media outlets, but then, at the same time, be surprised when this influences people and their behaviors," she said. "If you're going to do it, then you need to make sure you follow it up with education that people need to make responsible decisions."

It's crucial that parents and guardians talk to their kids about these topics and teach morals and values, but they can do only so much in limiting the amount of sexual content that their teenagers see on television, Wimberly said. Youths will have exposure to these programs outside of the home, such as at friends' houses or on the Internet.

Experts say television shows rarely portray the risks of sex and often don't mention contraception. But previous research from RAND showed that content that includes negative consequences, such as sexually transmitted diseases and unwanted pregnancies, can be educational for teens.

Previous RAND research also showed that teens who watch a lot of television with sexual content are more likely to initiate intercourse the following year.

The National Institutes of Health reported in July that teen pregnancies rose in the United States from 2005 to 2006 for the first time since 1991.

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