The study, published in Pediatrics, found that the LA teens who had sent racy texts were seven times more likely to be sexually active than those who said they'd never sexted.

"What we really wanted to know is, is there a link between sexting and taking risks with your body? And the answer is a pretty resounding 'yes,'" said Eric Rice, a social network researcher from the University of Southern California in Los Angeles, who led the study.

A study of Houston, Texas high schoolers out earlier this summer found that one in four teens had sent a naked photo of themselves through text message or email, and those kids were also much more likely to be having risky sex.

Rice's findings are based on 1,839 students in Los Angeles high schools, most of who were Latino. Three-quarters of them owned a cell phone that they used regularly.

On a survey sponsored by the Centers for Disease Control and Prevention, just over 40 percent of teens with a cell phone said they'd had sex, and about two-thirds used a condom the last time they did.

Rice said the rate of teen sexting in Houston may have been slightly higher than in Los Angeles because of demographic differences, but that overall the two reports are consistent.

"Somewhere in the middle is probably a pretty good estimate of what's going on nationally," said Jeff Temple, a psychologist and women's health researcher from The University of Texas Medical Branch in Galveston, who worked on the Houston study.

His research found that girls in particular who'd sent naked photos were more likely to engage in risky sex, to have had multiple recent sex partners or to use alcohol and drugs before sex.

"Sexting appears to be a reflection or an indication of actual sexual behavior," Temple told Reuters Health. "What they're doing in their offline lives is what they're doing in their online lives."

With sexting, aside from the risky sexual behavior, there's also the concern that naked photos will end up on the Internet and teens will be bullied online, or that students who receive explicit texts could be charged with child pornography.

Temple and his colleagues are currently working on a study to see what typically comes first among teens - sexting or actual sex.

Rice said that media coverage of sexting controversies could be a good way for parents or teachers to talk to teens about sexting and sex.

"Sexting might be an easier conversation for teachers to start having with teens than a full-on conversation that starts, 'Let's talk about sex,'" he said. SOURCE: bit.ly/jsoh2P

(Reporting from New York by Genevra Pittman at Reuters Health; editing by Elaine Lies)

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