Some sexual activities are riskier than others for getting or transmitting HIV. Anal sex is the riskiest type of sex for HIV transmission. If you don’t have HIV, being a receptive partner (or bottom ) for anal sex is the riskiest sexual activity for getting HIV. If you do have HIV, being the insertive partner (or top ) for anal sex is the riskiest sexual activity for transmitting HIV. There is extremely low to no risk of getting or transmitting HIV through activities like oral sex, touching, and kissing.
If the partner with HIV takes HIV medicine as prescribed and gets and keeps an undetectable viral load, they will not transmit HIV through sex.
Anal Sex
What is anal sex? Anal sex is when a penis is inserted into an anus. The partner inserting the penis is called the insertive partner. The partner receiving the penis is called the receptive partner.
What we know about anal sex
Anal sex is the riskiest type of sex for getting or transmitting HIV. Although receptive anal sex is much riskier for getting HIV than insertive anal sex, it’s possible for either partner—the insertive or receptive—to get HIV.
An HIV-negative receptive partner’s risk of getting HIV is very high because the lining of the rectum is thin. HIV can enter the body through this lining during anal sex from body fluids that carry HIV, including semen (cum) or pre-seminal fluid (pre-cum).
- On average, an HIV-negative receptive partner has about a 1 in 70 chance of getting HIV every time they have receptive anal sex with a partner who has HIV.
- Being the receptive partner for anal sex is about 13 times more risky for getting HIV from a partner with HIV than being the insertive partner.
- For women, anal sex is about 17 times more risky for getting HIV from a man with HIV than vaginal sex.
- If the partner with HIV takes HIV medicine as prescribed, and gets and keeps an undetectable viral load , you will not get HIV through sex with that partner.
An HIV-negative insertive partner is also at risk because HIV can enter the body through the opening at the tip of the penis (or urethra); the foreskin if the penis isn’t circumcised; or small cuts, scratches, or open sores anywhere on the penis. There is some evidence that circumcision decreases a man’s risk of getting HIV during sex.
- On average, an HIV-negative insertive partner has about a 1 in 900 chance of getting HIV every time they have insertive anal sex with a partner who has HIV.
- Being the receptive partner for anal sex is about 13 times more risky for getting HIV from a partner with HIV than being the insertive partner.
- For men, anal sex with a women with HIV is about 3 times more risky for getting HIV than vaginal sex.
- If the partner with HIV takes HIV medicine as prescribed, and gets and keeps an undetectable viral load , you will not get HIV through sex with that partner.
An uncircumcised penis still has foreskin. The inner lining of the foreskin is different than other types of skin and has more of the cells that HIV infects. The foreskin may also be easier to tear during sex, providing another way for HIV to infect the body. Also, HIV may be able to survive for a longer time in the space between the foreskin and the penis. There is some evidence that circumcision may decrease the insertive partner’s risk of getting HIV during anal sex. And, being circumcised greatly reduces the risk of a man from getting HIV when having sex with a women who has HIV. Finally, a person with an uncircumcised penis may also have a higher risk of getting other sexually transmitted diseases (STDs), such as syphilis or herpes, which can increase the risk of getting HIV.
Keep in mind that HIV can be found in pre-seminal fluid (pre-cum), which means there’s a risk for either partner to get HIV even if the insertive partner withdraws before ejaculating. Withdrawal before ejaculating may, in theory, reduce the receptive partner’s risk of getting HIV. But it does not change the insertive partner’s risk of getting HIV.
Many things can increase someone’s risk of getting HIV from anal sex besides sexual position (insertive vs. receptive). For example, the HIV-negative partner is more likely to get HIV if either partner has another sexually transmitted disease (STD). Also, if you are HIV-negative and have anal sex with a partner who has HIV, your chance of getting HIV is very high if that partner is not on HIV treatment and does not have an undetectable or suppressed viral load. If your partner with HIV takes HIV medicine as prescribed and keeps an undetectable viral load , they will not transmit HIV through sex.
You can get other STDs from anal sex even if you use a condom because some STDs are transmitted through skin-to-skin contact. And you can get hepatitis A and B, parasites like Giardia, and other bacteria like Shigella, Salmonella, Campylobacter, and E. coli from anal sex because they’re transmitted through feces.
If you’ve never had hepatitis A or B, there are vaccines to prevent these infections. Talk to a health care provider about your chances of getting hepatitis A or B and whether vaccination is right for you.
What you can do
Not having sex is a 100% effective way to make sure you don’t get or transmit HIV through sex. If you’re sexually active, you can lower your risk by choosing sexual activities that carry a lower risk for HIV than anal sex. You can also do other things to reduce your risk, including taking medicine to prevent or treat HIV and using condoms the right way, every time. Condoms and medicine to prevent or treat HIV are highly effective at preventing HIV if used correctly. But the medicines are much less effective if you don’t take them as prescribed, and condoms can sometimes break or come off during anal sex. Using a water-based or silicone lubricant can help prevent condoms from breaking or slipping.
Talking openly and frequently with your partner about sex can help you make decisions that decrease your risk of getting or transmitting HIV.