“Safer sex” is a term that can mean many things:

  • Avoiding bodily fluid exchange
  • Using prophylactics (such as male or female condoms)
  • Using HIV medications to prevent transmission of the virus
  • Limiting the number of sexual partners
  • Curtailing alcohol and drug use (which can impair judgment).

In fact, safer sex often involves a combination of these approaches.

The only way to know for sure whether you are HIV positive, even after an activity that is considered to be very low risk for HIV transmission, is to get tested. If you’ve contracted another sexually transmitted infection, it’s also a good idea to be tested for HIV.

Male Condoms (also known as external condoms)
Several studies have demonstrated that male condoms made of either latex or polyurethane are effective barriers against HIV. The theory behind using condoms is clear: They cover the penis and provide an effective barrier to exposure to secretions, such as semen and vaginal fluids, thereby blocking the sexual transmission of HIV.

Laboratory studies have been conducted to support this theory. These studies involved placing a solution containing HIV inside the condoms. No leakage of HIV across the latex or polyurethane condoms occurred during these studies. Similar studies have also demonstrated that these types of condoms also prevent other common sexually transmitted viral infections, such as herpes simplex virus (HSV) and hepatitis B virus (HBV).

Condoms made of natural materials—such as lambskin—are not a consistently effective barrier against many viruses. In one laboratory study, HIV was found to pass through microscopic holes in lambskin condoms. Studies involving HSV and HBV reported similar results.

A number of epidemiological studies—studies conducted in real-life settings where one partner is living with HIV and the other partner is not—have demonstrated that consistent use of latex (or polyurethane) condoms provide a high degree of protection against HIV. The key to effective protection is consistent and correct use of condoms.

Incorrect use of condoms can increase the risk of slippage or breakage, which diminishes their ability to protect against the virus. Inconsistent use—for example, failure to use condoms with every act of vaginal or anal intercourse—can lead to HIV transmission.

Polyurethane condoms are an effective alternative to latex condoms, especially for people with an allergy to latex. There have been at least six epidemiological studies of polyurethane condoms. Three of the studies found that slippage and breakage occur equally (and rarely) with both latex and polyurethane condoms. The three other studies found that polyurethane condoms are more likely to break than latex condoms (one study also demonstrated that polyurethane condoms are more likely to slip than latex condoms). Still, if used consistently and correctly, they are considered to be a highly effective barrier against the sexual transmission of HIV.

Female Condoms (also known as internal or receptive condoms)

The female condom, approved in 1993 for use in the United States, is a polyurethane pouch with flexible polyurethane rings at each end. It is inserted deep in the vagina, much like a diaphragm. The ring at the closed end holds the pouch in the vagina. The ring at the open end remains outside the vulva (vaginal opening). If inserted properly, it lines the vagina and the cervix, which helps to prevent pregnancy along with HIV and other sexually transmitted infections.

While female condoms are not approved for use during anal intercourse, some men who have sex with men (MSM) have reported using them for anal sex. However, at least one study has reported problems for the receptive partner using the female condom, including difficulty inserting the condom, discomfort and rectal bleeding (removing the inner ring may alleviate some of the problems experienced during anal insertion and removal). Several studies have also indicated that female condoms are not as effective as male condoms, largely because of the difficulty in using them correctly.

Only water-based and silicone-based lubricants should be used with latex condoms. K-Y Jelly, Wet and Astroglide are three examples of water-based lubricants that can be used with latex condoms. Examples of silicone-based lubricants include Millennium ID and Eros Bodyglide.

Never use oil-based lubricants, including hand or body lotion, baby oil, vegetable oil or shortening, massage oil, mineral oil or petroleum jelly (e.g., Vaseline). Oil-based lubricants can damage latex and cause latex condoms to tear more easily.

Some pre-lubricated condoms and separately sold lubricants contain a chemical called nonoxynol-9. While nonoxynol-9 has been shown to kill sperm (and potentially reduce the risk of pregnancy) and various sexually transmitted infections, some men and women are allergic to this chemical. This can cause irritation inside the vagina and anus, which can increase the risk of HIV transmission if the condom breaks.

Antiretroviral (ARV) Therapy
HIV medications can also be used to prevent sexual transmission of the virus. Pre-exposure prophylaxis (PrEP) is an HIV prevention tool in which an HIV-negative person takes antiretroviral medication to reduce the risk of contracting HIV. Post-exposure prophylaxis (PEP) involves taking a short course of ARV drugs, usually for a month, to prevent HIV transmission after a high-risk exposure. Treatment as prevention (TasP) refers to taking antiretoivrals to prevent sexual tranmission. People living with HIV who maintain an undetectable viral load have effectively no risk of transmitting the virus via sex, a concept known as Undetectable Equals Untransmittable, or U=U. 

Last Reviewed: February 1, 2022