The Centers for Disease Control and Prevention has revised its 2015 estimate of the factor by which condoms reduce the risk of transmitting HIV through anal sex, upping the figure from 70 percent to just over 90 percent. To reach this new estimate, researchers conducted a meta-analysis of four studies that included HIV-negative men who have sex with men. Among the men who reported never or sometimes using condoms, for each additional HIV-positive partner with whom they had receptive anal intercourse, their risk of contracting HIV increased by 83 percent. For the men who reported always using condoms, their risk per additional such partner rose by just 7 percent. Comparing the difference between these two rates, the study authors concluded that when an HIV-negative man has receptive intercourse with an HIV-positive man, condoms reduce his chance of contracting the virus by 91 percent.
Prevention: Condom Update
New findings suggest that condoms cut HIV risk by just over 90 percent for anal sex.