Is a squirt of foam or dollop of gel likely to meet a woman's HIV prevention needs? Far from it, according to most research that's been conducted on vaginal microbicides -- those HIV-killing chemicals found in some foams, gels and lubes.

Historically, women have borne most of the responsibility in preventing unwanted pregnancy. With HIV prevention, however, the reverse is true. Besides Reality, the relatively expensive and thus far less-than-popular female condom, the woman-only arsenal of HIV prophylactics consists solely of vaginal microbicides. These agents -- which kill bacteria, viruses and parasites -- have limited effectiveness in preventing HIV transmission and may actually increase a woman's risk of infection.

Nonoxynol-9 and octoxynol-9 -- both commonly found in gels, foams, suppositories and lubricants -- are the only two vaginal microbicidal agents currently approved in the United States.

"Such compounds have the potential to cause significant vaginal irritation that may actually augment the risk of HIV transmission," write Christopher Elias and Lori Heise of the New York City-based Population Council.

Vaginal microbicides are only one piece of the HIV prevention puzzle. Researchers say development of additional female-controlled HIV prevention options are slow in coming because of gender bias, the unprofitability of microbicides and manufacturers' fear of product-liability suits.

The Philadelphia-based pharmaceutical company Biosyn currently is testing the vaginal microbicide C31G in a phase I safety trial. Test results of C31G thus far show the drug to have a lower tissue irritation level than nonoxynol-9 and to have activity against a broad spectrum of sexually transmitted diseases. Other vaginal microbicides in the drug pipeline are in even more preliminary testing stages than C31G. None of these products are likely to make it to the neighborhood drug store for several years.

HIV infection rates are skyrocketing among women worldwide, and the lack of inexpensive, safe, female-controlled prevention methods is partly responsible for this global explosion. Sadly, many women remain uninformed as broad medical research on vaginal microbicides continues to be neglected.