DO SPERMICIDES CONTAINING NONOXYNOL-9 PREVENT SEXUALLY-TRANSMITTED INFECTIONS - A METAANALYSIS

Background and Objectives: There are conflicting opinions on whether t o recommend spermicides containing nonoxynol-9 for prevention of sexua lly transmitted diseases, including human immunodeficiency virus (HIV) . Goal: To systematically review and summarize the medical literature on the effect of spermicides containing nonoxynol-9 on prevention of g onorrhea, chlamydial infection, and HIV, Study Design: Meta-analysis. Potential articles were identified through computerized literature sea rches. Articles were included if the design was clinical trial, cohort , case-control, or cross-sectional; original outcome data were present ed for gonorrhea, chlamydial infection, or HIV; and spermicides contai ning nonoxynol-9 were used separately from other barrier methods. Stud y characteristics including design, population, spermicide dose, and d elivery method were abstracted. Relative risks (RR) and 95% confidence intervals (CI) were determined from information published in the stud y or from study authors. Summary risk estimates were computed for clin ical trials. Results: Twelve eligible articles were identified, includ ing six clinical trials and six observational studies. Eleven articles evaluated gonorrhea; each found a reduced risk of infection with sper micide use. Among six clinical trials, the summary RR was 0.62 (95% CI , 0.49-0.78). The five articles evaluating chlamydial infection also f ound significant reduction among spermicide users, with the four clini cal trials having a summary RR of 0.75 (95% CI, 0.62-0.91). The degree of spermicidal protection against gonorrhea and chlamydial infection did not differ materially among studies with different study designs o r spermicidal preparations (i.e., sponge, gel, suppository, or film). Three studies evaluated degree of protection according to consistency of use and found stronger protection with more consistent use. The two studies on spermicidal prevention of HIV had contrasting results: An observational study found a significant protective effect (RR = 0.1), whereas a clinical trial found a nonsignificantly increased risk (RR = 1.7). Conclusions: Nonoxynol-9-containing spermicides have an appreci able protective effect against both gonorrhea and chlamydial infection , and wider use of spermicides might substantially reduce the incidenc e of these diseases. However, insufficient data exist to judge their e ffect on HIV transmission, and more research on the effect of nonoxyno l-9 on HIV transmission is urgently needed to make evidence-based clin ical decisions and public health recommendations in the future.