The use of nonoxynol-9 for protection against cervical gonorrhea

Although condoms are the best defense against sexually transmitted disease, little is known about the effectiveness of female-controlled methods containing nonoxynol-9 as backup protection when condoms are not being used. To assess the extent to which nonoxynol-9 protects women against gonorrhea, a cohort of 303 female sex workers (prostitutes) in Yaounde, Cameroon, were asked to use condoms and suppositories containing nonoxynol-9 at every sexual encounter and to record daily sexual activity and use of condoms and suppositories on coital logs that were reviewed monthly. Evidence of gonorrheal infection was based on a positive gonorrhea culture. Stratified analysis and proportional hazards regression were used to estimate rate ratios. Forty-one women enrolled in the study were excluded from the current analysis. The estimated incidence of gonorrhea was 6.2 infections per 100 person-months of observation. Incidence rate ratios estimated from proportional hazards regression models controlling for condom use showed that using nonoxynol-9 during acts not protected by condoms reduced the risk of infection. Although the protective effect of condoms against sexually transmitted disease is greater than that afforded by nonoxynol-9, using nonoxynol-9 when condoms are not used is a far better strategy in gonorrhea prevention than using no method at all.