One-third of U.S. girls sexually active by age 15.(Gynecology)

BOSTON -- By age 15, more than a third of American girls say they are sexually active, according to a Centers for Disease Control and Prevention survey. About 26% have had oral sex, 26% have had vaginal intercourse, and another 8% have had oral sex without intercourse. The proportion that is sexually active grows substantially every year thereafter, according to a presentation at a conference on contraceptive technology sponsored by Contemporary Forums.

Accurate data on teenagers' sexual behavior are important for any clinician concerned about unintended pregnancy and the spread of sexually transmitted infections (as well as the psychological and emotional health of young women). If, as expected, the Food and Drug Administration approves a human papillomavirus vaccine in mid-2006, public health officials will need to accurately predict the age when girls become sexually active in order to recommend an age for vaccination.

Media reports increasingly suggest that as conventional teen dating and romance plunge, oral sex and casual sexual "hookups" among so-called "friends with benefits" have become commonplace. Anecdotal reports of teen promiscuity have seemed to proliferate, after a reporter described teenagers he met through an Internet site where high school and college students post their profiles, chat, and arrange meetings for sex in, "Friends, Friends With Benefits, and the Benefits of the Local Mall" (New York Times, May 30, 2004).

According to the CDC data, the typical teen who is sexually active has one or two partners, ...