Before we talk about sex without condoms here's a couple of things you should know. 

  1. People living with HIV who have an undetectable viral load cannot pass on the virus sexually. This is known as HIV-undetectable / U=U / HIV-U.
  2. PrEP can be taken by HIV-negative people to stop the transmission of HIV. When taken correctly it has a 99% success rate. 
  3. Even if you have sex without condoms with someone who is HIV-undetectable or on PrEP, you are at risk of picking up other STIs.

Now, let's talk about sex without condoms. 

Most gay and bisexual men who have HIV caught it from having penetrative sex without a condom. As far as men who have sex with men goes, getting having sex without a condom (and your partner is not HIV-undetectable), and having your partner cum inside you, is the riskiest thing you can do. This is because the lining of the bum can absorb liquids directly into your bloodstream. If there’s HIV in his cum, and it into your rectum, that will be absorbed too. Having sex without him cumming inside you is lower risk but, as there is HIV in pre-cum too, there is still a risk of HIV transmission.

In group sex it’s theoretically possible to catch HIV from having sex even if your partner is HIV-negative, if they has been with someone who is HIV-positive and then has sex with you immediately afterwards. This is because there could be traces of HIV-infected anal mucus or blood on his penis.

Having sex without condoms is also high risk for most other STIs, including chlamydia, gonorrhoea, herpes, syphilis, warts, hepatitis B and it is now thought that you can catch hepatitis C as well. Condoms provide an effective barrier against most STIs, including HIV, although some STIs, such as syphilis and warts, can still be transmitted if the condom does not cover the entire infected area, such as the base of the penis. If you are infected with an STI in your bum, it will increase the chances of you being infected with HIV if you are HIV-negative. If you are HIV-positive, not undetectable and have an STI, it is likely that there will be higher concentrations of HIV in all of your body fluids, including blood and anal mucus, and so you will be more infectious. A person who is living with HIV and undetectable cannot pass on the virus sexually.

What if I have sex without a condom?

Having sex with someone with a condom is less risky than having sex without a condom if you're both not on PrEP and/or HIV-undetectable, but it is still one of the riskiest sexual practices. If you are HIV-negative, having unprotected sex with someone is more likely to lead to infection than oral sex. This is because the anal mucus that lines the bum (we all have it) can contain a very high concentration of HIV. The mucous membrane just inside the tip of the penis and the foreskin can absorb liquids, like anal mucus, directly into the bloodstream. 

Other infections in or around his bum, such as chlamydia, gonorrhoea, herpes, syphilis, warts and hepatitis B can be passed to the guy through his urethra (the tube you pee through). Condoms can prevent most of the infections that you can get from having sex, although it’s worth remembering that some STIs can be transmitted even if you use condoms.

How risky is being top versus bottom and having sex with condoms?

While it is rare, condoms can break during anal sex and this could make it possible for HIV or other STIs to be transmitted. Condom breaks usually occur because condoms are used incorrectly or are used for long sessions without changing them. If you use condoms correctly with plenty of water-based lube, it will greatly reduce the chances of them breaking.

If you are having group sex, it’s also important to change condoms for each partner. This is because it’s theoretically possible that traces of HIV-infected anal mucus or blood could remain on a condom after a guy with HIV has sex. This is also true for other STIs, including hepatitis C. While condoms offer protection against HIV and most STIs, they cannot prevent them all. Even if you always use condoms for sex we recommend that you get regular sexual health screens at a GUM clinic and continue to test for HIV on an annual basis.

What next

  • Every sexually active person should get tested at least once a year. If you are having lots of sex then you should test more often.
  • It roughly takes 10 days for STIs to show up in a test, though some people may start to experience symptoms after three days. Most people see symptoms after about a week. Though you may not show any symptoms at all.
  • It takes about four weeks for HIV to show up on a test. If you think you've put yourself at risk of HIV you must wait four weeks to test otherwise it's likely the test will show up negative. 
  • If you've put yourself at risk you can go to any GUM clinic and ask for PEP. If taken within 72 hours after sex, and taken correctly, PEP can stop you becoming HIV-positive. PEP is a month long course of medication. 
  • If you are HIV-negative and have sex without condoms we recommend that you look into PrEP. If taken correctly, PrEP has a 99% success rate in stopping HIV. 

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