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MONDAY, Jan. 14 (HealthDay News) -- Nearly a third of American teenage girls  say that at some point they've met up with people with whom their only prior  contact was online, new research reveals.

For more than a year, the study tracked online and offline activity among  more than 250 girls aged 14 to 17 years and found that 30 percent followed  online acquaintance with in-person contact, raising concerns about high-risk  behavior that might ensue when teens make the leap from social networking into  real-world encounters with strangers.

Girls with a history of neglect or physical or sexual abuse were particularly  prone to presenting themselves online (both in images and verbally) in ways that  can be construed as sexually explicit and provocative. Doing so, researchers  warned, increases their risk of succumbing to the online advances of strangers  whose goal is to prey upon such girls in person.

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