Children who participate in oral sex in the 9th grade will be having intercourse by the 11th, according to results of a new survey conducted by researchers at UC San Francisco and UC Merced.   Solution: Sex education should include oral sex, they conclude.

With results likely to shore up opposition to having sex education in schools at all, the study debunks the notion that oral sex acts as a protective measure delaying the onset of further sexual activity.   Study results are published online by the Archives of Pediatrics and Adolescent Medicine and will appear in the March 2011 print issue of the journal.

The researchers followed more than 600 students at two northern California high schools from the ninth grade through the end of 11th grade. All participants received their parents' consent to participate. From 2002 to 2005, the students completed a survey every six months during class time about their sexual experiences. Responses were consistent across different ethnic groups, socioeconomic levels and genders. 

Bonnie Halpern-Felsher, PhD, senior author of the study and a professor of pediatrics at UCSF said, "I see most of the health policies out there and guidelines for preventive services talking about sex generally, but they do not specify oral sex. That is an important distinction because teens don't consider oral sex to be sex, and many are not aware of the risks involved."

Nor do many adults consider it sex.   During President Clinton's testimony that led to his impeachment, he stated that oral sex was not sex.

Among teens who reported becoming sexually active during the three-year study, most said they had intercourse for the first time after or within the same six-month period of initiating oral sex. According to Halpern-Felsher, this indicates oral sex is influencing the onset of riskier sexual behavior, underscoring the need to encourage open, honest discussion about sexual activity.

"We need to make sure teens know that if they do choose to have oral sex, certainly it does involve less risk than intercourse, but it's not risk-free," Halpern-Felsher said. "We also have to be sure to ask teens if they have any questions. It sounds simple, but it is a very important step that parents and healthcare providers should be taking."

"Our study demonstrates that through its relationship with intercourse, oral sex contributes to the total risk associated with sexual activity among teens, including sexually transmitted diseases and pregnancy," said Anna Song, PhD, first author of the study and an assistant professor of psychological sciences at UC Merced. 

Teens who had engaged in oral sex by the end of ninth grade were at the highest risk of having sexual intercourse during high school. They had a 25 percent chance of having intercourse by the end of ninth grade and a 50 percent chance by the end of 11th grade, with most engaging in both oral sex and intercourse during the same six-month period.

In comparison, adolescents who delayed oral sex until the end of 11th grade had only a 16 percent chance of having intercourse by the end of that school year. The researchers explain that, based on these findings, the first two years of high school appear to be a particularly vulnerable period.

"We don't want parents to hear about these findings and say, 'Thanks for the information. I'm locking up my teen until graduation,'" Song said. "The most effective reaction is to use this knowledge to have an informed conversation with kids that addresses different types of sexual behaviors, including oral sex."

In a previous survey of adolescent sexual behavior, Halpern-Felsher concluded that 20 percent of adolescents have oral sex by the end of ninth grade and more than half of teenagers 15 to 19 years old engage in oral sex with members of the opposite sex.