Seventeen-year-old girls are more likely to have sexual contact with another girl than they were a decade ago, according to a new study by the U.S. National Survey of Family Growth.

Eleven percent of the girls surveyed had sexual contact with another girl in the 2006-2008 version of the study, versus 5% in the 2002 version, according to the Williams Institute, which analyzed the numbers.

The same group has also reported less sexual activity with boys, leading to less occurrences of pregnancy, and a lower need for emergency contraception.

"Factors that may account for this drop include our findings that more were waiting until later in adolescence to become heterosexually involved, more were using emergency contraception if they were heterosexually active, and perhaps even that more were engaging in same-sex behavior," Lead author Dr. Nanette Gartrell said in a statement Tuesday. "It will be interesting to see if the next cycle of NSFG data collection reveals whether these changes are a long-term trend."

Image via Photos.com.

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