A recent study of 990 prostitutes in four countries found that the spermicide nonoxynol-9 may increase the risk of contracting the HIV-AIDS virus for sexually active women. Evidence from a study sponsored by the Joint United Nations Program on HIV/AIDS (UNAIDS) shows that when used frequently, the chemical’s irritant causes breaks or “lesions” in the vaginal lining, thereby increasing women’s vulnerability to HIV. Some health officials have expressed concern that utilizing this spermicide is not advisable for any woman at risk of HIV infection. Nonoxynol-9, which has been used for over four decades as a contraceptive, was used by over 9 million women in 1995 alone. Public health experts will convene at a meeting sponsored by the World Health Organization this fall to determine how to advise women who use nonoxynol-9 of its risks associated with HIV.