All the more reason for parents to be on the lookout for their kid’s cell phone behavior.  If you catch them sending sex based messages, don’t let them try to tell you it’s no big deal. According to a study from the School of Social Work at the University of Southern Californian teens who engage in "sexting" -- that is, sending and receiving sexually explicit texts and images -- are most likely taking other sexual risks, too.

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A HealthDay News study reveals that teens who "sext" are seven times more likely to be sexually active and significantly more apt to be having unprotected sex, reports. Of those who owned a cell phone, 15 percent admitted they had engaged in sexting, and 54 percent knew someone else who had sent a sext message.  And parents, don’t fall for the  “Mary’s mom doesn’t care if she does it” type argument.

Among those who sexted, it was rare that this was the only sexually risky behavior in which they were engaged. Teens were 17 times more likely to sext if they had friends who did it, since they viewed it as normal behavior if a friend did it.