"Preventing the Sexual Transmission of HIV, the Virus that Causes AIDS -- What You Should Know about Oral Sex," a new fact sheet created by the U.S. Centers for Disease Control and Prevention (CDC), outlines both the theoretical and documented risk of HIV transmission through unprotected oral sex. According to the fact sheet, numerous studies have demonstrated that oral sex can result in the transmission of HIV and other STDs.

Transmission through Oral-Penile Contact

• There is a theoretical risk of HIV transmission for the receptive partner because infected pre-ejaculate fluid or semen can get into the mouth. For the insertive partner, there is a theoretical risk of infection because infected blood from a partner's bleeding gums or an open sore could come in contact with a scratch, cut, or sore on the penis. Although the risk is many times smaller than anal or vaginal sexual intercourse, it has been documented that HIV has been transmitted to receptive partners through fellatio, even in cases when insertive partners did not ejaculate.

Transmission through Oral-Vaginal Contact

• There is a theoretical risk of HIV transmission for the insertive partner because infected vaginal fluids and blood can get into the mouth. Likewise, there is a theoretical risk for the receptive partner if the infected blood from oral sores or bleeding gums comes in contact with vulvar or vaginal cuts or sores. There have been a few documented cases of HIV transmission most likely resulting from oral-vaginal sex.

Transmission through Oral-Anal Contact

• There is a theoretical risk of HIV transmission for the insertive partner if there is exposure to infected blood, either through bloody fecal matter or cuts/sores in the anal area. Also, there is a theoretical risk for the receptive partner if infected blood in saliva comes in contact with the anal/rectal lining. There has been one published case of HIV transmission associated with oral-anal sexual contact.

The CDC points out how important this information is in light of recent findings about teen sexual behavior. Many adolescents who engage in oral sex do not consider it sex, therefore they may use oral sex as an option to experience sex while still, in their minds, remaining abstinent. In a recent national survey of teens conducted by the Kaiser Family Foundation, 26% of sexually active 15 to 17 year olds surveyed responded that one "cannot become infected with HIV by having unprotected oral sex."

To lower any risk of getting HIV from oral sex, the CDC recommends the use of latex condoms (cut open), plastic food wrap, or a dental dam as a physical barrier to prevent transmission of HIV and other STDs.

For more information: U.S. Centers for Disease Control and Prevention, 1600 Clifton Road, Atlanta, GA 30333; Public Inquiries Office: 404/639-3311; Web site: http://www.cdc.gov; Copy of fact sheet: http://www.cdc.gov/nchstp/od/oral_sex.htm