Spermicide Doesnt Prevent STDs, Condoms Still Best Choice For HIV Protection

About the Study

Research sponsored by UNAIDS, a Joint United Nations program on HIV/AIDS, studied 563 HIV-negative female sex workers (average age 26) in South Africa, Thailand, Benin, and Côte d’Ivoire over four years. These women were recruited from nearby clinics and were included in the study if they were:

• Not users of intravenous drugs or intravaginal spermicides other than the study gel containing nonoxynol-9
• Not pregnant or planning to become pregnant within the next six months
• Not allergic to latex or a study-gel ingredient
• Willing and able to give informed consent and to follow the study instructions
• At least 16 years old (in South Africa) or 18 years old (Benin, Côte d’Ivoire, and Thailand)

At the start of the study, each woman provided information on her sexual behavior (including methods of contraception and prevention of sexually transmitted infections) and sociodemographic characteristics. All women underwent a variety of tests for STDs and received HIV pre-test and post-test counseling and safer-sex messages. If a curable STD was diagnosed, the women were given treatment according to local guidelines. Women were randomly assigned to receive a supply of study gel (nonoxynol-9 or placebo) and male condoms (latex, not lubricated with spermicides) to fulfill their needs until the next visit. Women were asked to return to the clinic each month for a gynecologic exam, HIV testing, STD testing and treatment, and to answer questions about sexual behavior, use of the condoms and gel, and the gel’s acceptability.

The researchers compared the number of HIV, chlamydial, and gonorrheal infection cases among users of the nonoxynol-9 gel versus non-users (placebo). They also looked at the acceptability of the gel for long-term use.

The Findings

Among high-risk women, the nonoxynol-9 vaginal gel did not protect against STDs. In fact, in three out of the four centers studied, women using the nonoxynol-9 dose more than 3.5 times per day had nearly double the incidence of HIV infection compared with those using a placebo gel. The results also suggested that women using the nonoxynol-9 gel were at greater risk of contracting chlamydia and gonorrhea. These results remained the same even after adjustments were made for the different centers and self-reported sexual behavior, such as frequency of vaginal sex not protected by condoms or unprotected anal sex.

Though the spermicide gel was not effective at protecting these women from HIV and other STDs, there was at least one promising finding. The study results did show that the trial procedures—safer sex counseling, providing condoms, and frequent STD testing and treatment—reduced the risk of HIV infection in study volunteers compared to female sex workers who did not receive any intervention.

There are a number of limitations to this study. For instance, more women in the nonoxynol-9 group dropped out of the study than in the placebo. If this loss was associated with contracting STDs, then the adverse effects of the nonoxynol-9 gel would have been understated. Researchers also found that those who stayed in the trial were older, less educated, and had been sex workers longer than those who did not participate in the study. This means that the women in the study may not be representative of the whole population of female sex workers in these countries. Researchers also did not adjust the results to account for other STDs that might have increased these women’s susceptibility to HIV (such as hepatitis, herpes, genital warts, etc.). Finally, sexual behavior was self-reported, which could compromise the accuracy of the information provided by the women. For these reasons, the results of this study cannot necessarily be applied to the general female population, especially women who aren’t at high risk of getting STDs.

How Does This Affect You?

While the results of this study were unexpected, its findings do highlight the importance of using condoms for protection against HIV and other sexually transmitted diseases or infections. For women at low risk of exposure to STDs, nonoxynol-9 combined with condoms still remains an effective method for preventing pregnancy. If you are sexually active you can also reduce your risk of getting HIV and other STDs by avoiding high-risk behaviors like unprotected sex, multiple sex partners, and intravenous drug use. Check with your doctor promptly if you think you may have been exposed to a sexually transmitted infection.