This is a question out of curiosity. I know that the chances of men contracting the disease via heterosexual sex are lower than those of women. Howver, my question is: If a woman engages in sex with an HIV positive man, is there any chance that she will not get infected?

Hello,

Yes, the estimated per-episode risk for a woman to acquire HIV from an HIV-positive man as a consequence of unprotected receptive penile-vaginal intercourse is 10 per 10,000 exposures. Although this estimated risk is smaller than many people would anticipate, it is nonetheless very significant. There are, of course, a large number of variables that come into play for each specific instance of HIV transmission viral strain, viral load, concurrent STDs, individual host immune response, etc. Certainly the take-home message is that heterosexual transmission accounts for the vast majority of the over 40,000,000 worldwide HIV cases. Consequently, safer sexual prevention techniques remain essential.

Stay safe. Stay well.

Dr. Bob