Unsafe sex has a high risk of spreading HIV. The greatest risk is when blood or sexual fluid touches the soft, moist areas (mucous membrane) inside the rectum, vagina, mouth, nose or tip of the penis. These can be damaged easily, which gives HIV a way to get into the body.
Vaginal or rectal intercourse without protection is very unsafe. Sexual fluids enter the body, and wherever a man's penis is inserted it can cause small tears that make HIV infection more likely. The receptive partner is more likely to be infected, although HIV might be able to enter the penis, especially if it has contact with HIV-infected blood or vaginal fluids for a long time or if it has any open sores.
Most sexual activity carries some risk of spreading HIV. To reduce the risk, make it more difficult for blood or sexual fluid to get into your body.
Be aware of your body and your partner's. Cuts, sores or bleeding gums increase the risk of spreading HIV. Rough physical activity also increases the risk. Even small injuries give HIV a way to get into the body.
Use a barrier to prevent contact with blood or sexual fluid. Remember that the body's natural barrier is the skin. If you don't have any cuts or sores, your skin will protect you against infection. However, in rare cases HIV can get into the body through healthy mucous membranes. The risk of infection is much higher if the membranes are damaged.
The most common artificial barrier is a condom for men. You can also use a female condom to protect the vagina or rectum during intercourse. Factsheet 153 has more information on condoms.
Lubricants can increase sexual stimulation. They also reduce the chance that condoms or other barriers will break. Oil-based lubricants like Vaseline, oils or creams can damage condoms and other latex barriers. Be sure to use water-based lubricants.
Oral sex has some risk of transmitting HIV, especially if sexual fluids get in the mouth and if there are bleeding gums or sores in the mouth. Pieces of latex or plastic wrap over the vagina, or condoms over the penis, can be used as barriers during oral sex. Condoms without lubricants are best for oral sex. Most lubricants taste awful.