From a sexual health perspective, oral sex carries no risk of pregnancy. However, there is a risk of transmitting other STDs this way, including HIV, although it's lower than with anal or vaginal sex. In recent years, oral cancer caused by the human papillomavirus (HPV) has also become a concern with oral sex. These risks can be greatly reduced through the use of condoms.
Oral sex is also known as fellatio, oral-genital sex, or cunnilingus. One partner may also refer to oral sex by saying that they "went down on" the other.
More About Oral Sex
Oral sex is considered a common sexual behavior among both gay and straight couples, and a number of positions are used in performing oral sex. According to the Janus Report on Sexual Behavior, 18% of women report a preference for oral sex to achieve orgasm, compared to 10% of men. Women are also more likely to achieve orgasm through oral sex than through vaginal sex.