Condoms with nonoxynol-9 (N-9) ? do they increase HIV risk?

You heard right ? here's the scoop: The Joint United Nations Programme on HIV/AIDS (UNAIDS) [2] conducted a four-year study on the effectiveness of nonoxynol-9 (N-9) gel as a microbicide (a chemical substance that kills viruses and bacteria) against HIV. The study found that the women who used N-9 were not only unprotected from HIV, but became infected with the virus at an approximately 50 percent higher rate than the placebo-gel-using participants. These research results suggest that N-9 may have facilitated HIV transmission. Previous studies have shown N-9's potential to irritate or cause lesions in the tender mucous membranes of the rectum and vagina in some users, increasing the likelihood of the transfer of HIV.