Teenage sexting usually is done as part of a relationship or would-be relationship between teens, the Pew focus groups found.

Some teens send sexts only to people with whom they are in a relationship; but those messages often are forwarded to people outside the relationship, especially after a breakup, according to the interviews.

"It doesn't take that many people creating these images for a lot of people to see them," said Amanda Lenhart, a senior research specialist at the Pew Internet & American Life Project and author of the sexting report.

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