Questions and Answers: Adolescent Sexuality
Unfortunately, there is a limited amount of scientific data on adolescent sexual behavior. Research designed to examine this subject is often controversial as adults seem to falsely fear that asking young people about sex is tantamount to giving them ideas and encouragement. While we have some information about sexual intercourse and contraceptive use among teens, we know very little about other behaviors such as masturbation, oral sex, and anal intercourse. In addition, much of the current research is limited to heterosexual behaviors.
One of the primary sources of data, is the Youth Risk Behavior Surveillance System (YRBS) conducted by the U.S. Centers for Disease Control and Prevention (CDC). This study measures sexual behaviors, alcohol and other drug use, tobacco use, unhealthy dietary behaviors, physical inactivity, and behaviors that contribute to unintentional injuries and violence. The YRBS is conducted every two years with students in grades nine through 12 at high schools across the country. It provides the most current information about adolescent sexual behavior, including history of sexual intercourse, number of sexual partners, and contraceptive use. The most recent YRBS was released in 2007.
In 2002, the NSFG asked individuals ages 15–44 the age at which they first had intercourse. The mean age for women was 17.4 and the mean age for men was 17.0.  We have to remember, however, that this data includes individuals of different generations. The YRBS does not ask young people the age at which they first had intercourse, however, one question on the surveys asks students if they had engaged in sexual intercourse before age 13. In 2005, 6.2 percent of high school students reported having engaged in sexual intercourse before age 13.
According to the 2007 YRBS, 46.8 percent of high school students (45.7 percent of high school females and 47.9 percent of high school males) reported having engaged in sexual intercourse.  The NSFG had similar results, finding that 45.5 percent of young women and 45.7 percent of young men ages 15–19 have engaged in sexual intercourse. The data show that as young people get older they are more likely to have engaged in intercourse. According to the YRBS, 63.1 percent of high school seniors reported having had engaged in sexual intercourse, and the NSFG found that 68.8 percent of young women and 64.3 percent of young men ages 18–19 had engaged in sexual intercourse.
The YRBS only asks young people about vaginal intercourse. The NSFG, however, also included a question on oral sex. It found that 54.3 percent of females ages 15–19 had engaged in oral sex with a male and 55.2 percent of males ages 15–19 had engaged in oral sex with a female. In addition, a study by the Kaiser Family Foundation found that 36 percent of young people ages 15–17 reported having engaged in oral sex. Interestingly, some of these young people (24 percent) reported having oral sex to avoid having intercourse. 
Research shows that many young people are using pregnancy- and disease-prevention methods. According the YRBS, 62.8 percent of sexually active high school students (those students who reported having had sexual intercourse in the three months prior to the survey) used a condom the last time they had intercourse. And, 17.6 percent of sexually active high school students report using birth control pills to prevent pregnancy before their last act of sexual intercourse. The NSFG asked young people whether they had used a condom the first time they had sexual intercourse and found that 66.4 percent of young women and 70.9 percent of young men ages 15–19 had done so.
There is very little research into what motivates young people’s decisions regarding sexual behavior. One survey conducted by Seventeen Magazine and the Kaiser Family Foundation asked sexually active participants why they had “had sex” and participants who were not sexually active why they made that decision. Of participants ages 15–17 who had “had sex,” 51 percent said when they had sexual intercourse for the first time it was because they “met the right person,” 45 percent said it was because “the other person wanted to,” 32 percent said it was because they were “just curious,” 28 percent said it was because they “hoped it would make the relationship closer,” and 16 percent said it was because “many of their friends already had.” 
 All NSFG is information taken from: Key Statistics NSFG, Cycle 6 (2002), (Hyattsville, MD: National Center for Health Statistics), accessed 11 March 2008, http://www.cdc.gov/nchs/about/major/nsfg/abclist.htm.