How can the sexual transmission be prevented?

How can the sexual transmission be prevented?

Male 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 sexual transmission of HIV infection.

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 was demonstrated. Similar studies have also demonstrated that other common sexually transmitted viral infections, such as herpes simplex virus (HSV) and hepatitis B virus (HBV), are also prevented with the use of these two types of condoms.

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.

There have been a number of epidemiological studies—studies that are conducted in real-life setting, where one partner is infected with HIV and the other partner is not—that have demonstrated consistent use of latex (or polyurethane) condoms provide a high degree or protection against HIV. However, the key to effective protection is consistent and correct use of condoms.

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

A word about polyurethane condoms: They 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 that slippage and breakage occurs 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 (with one of the studies also demonstrating 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

The female condom, approved in 1993 for use in the United States, is a polyurethane pouch with flexible polyurethane rings and 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 stays 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 MSM have reporting 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.