If your adolescent is sexting, they may be already sexually active and engaging in risky behavior, a new study suggests.Researchers are trying to better understand if young people are at greater risk for HIV or other sexually transmitted diseases because they are sending sexually explicit photos or text messages via cell phones."Sexting" is not an alternative to "real world" sexual behavior among adolescents, according to a new study published Monday in the journal Pediatrics."The same teens who are engaging in digital sex risk taking through sexting are also the same teens that are engaging in sex risk with their bodies in terms of being sexually active and not using condoms," said lead study author Eric Rice, an assistant professor at the University of Southern California's School of Social Work in Los Angeles.A 2009 report from the Pew Research Center found that some teens "view sexting as a safer alternative to real life sexual activity."While the term "sexting" may also include messages also sent over the Internet, this particular study looked solely at cell phone text messages and images. It was conducted via questionnaire in the Los Angeles Unified School District. Researchers surveyed 1,839 students ages 12 to 18 at random. Most were Latino or African-American. Three-quarters of those surveyed had cell phones."Even though a minority of teens sext - we only found 15% - but that 15% are much riskier with their physical sexual behaviors as well as their digital sexual behaviors," says Rice.He add that teens who reported sexting were seven times more likely to be sexually active than their peers who did not sext.The data suggests there are norms about sexting, according to Rice, meaning teens are starting to think that sexting is a normal part of their behaviors. More than half of the teens surveyed reported that they had a friend who sexted."A lot of young people think that their friends are sexting, and if you think that your friends are sexting, you're much more likely to sext yourself," he said - 17 times more likely, according to study."I think that the implications are that teens who are sexting may be at greater risk for sexually transmitted diseases because the teens who sext are about 1.5 times more likely to not use condoms when they're having sex," in addition to increasing the risk of teen pregnancy, Rice says.This study was conducted in only one urban area; the authors realize that some of the results may not accurately represent rural areas. In addition, recent nationwide research found much lower rates of sexting.However, Rice said this information can be valuable for parents."We [parents, clinicians, educators] should be talking about sexting and the fact that it's part of the risky sex behaviors and it's not just something that exists in a virtual space, so to speak," he said."Talking about sexting might be easier for [parents] than talking about sex and it could lead into a larger conversation about sex."