It is possible to get HIV and other STDs during oral sex if your partner is infected, although the risk for transmitting certain STDs (like HIV) is generally lower from oral sex than from vaginal or anal sex without a barrier (like a condom or a dental dam).
Still, it’s a good idea to use a barrier when giving oral sex to prevent fluids (like semen, blood, vaginal fluids) from entering your mouth. It’s also a good idea to use a barrier when receiving oral sex,because some STDs can be passed from the mouth, throat or lips to the genitals or anus.
For oral sex on a penis, you should use a non-lubricated latex or polyurethane (plastic) condom. For oral sex on a vagina or anus, you should use a latex barrier (like a natural rubber latex sheet, dental dam or cut-open condom that makes a square) between your mouth and your partner’s genitals.
Male latex condoms and other barrier methods, when used consistently and correctly – meaning EVERY time, and from start to finish – are highly effective in preventing the spread of HIV. They also reduce the risk of many other STDs.
To further reduce the risk of getting or passing on an STD, see a health care provider about getting tested before becoming sexually intimate, and talk openly with your partner(s).