Laboratory studies indicate that the female condom (Reality) is an effective mechanical barrier to viruses, includ- ing HIV, and to semen. The first female condom approved for use in the United States consisted of a lubricated polyure- thane sheath with a ring on each end that is inserted into the vagina. A newer version made from nitrile is now available in the United States. A limited number of clinical studies have evaluated the efficacy of female condoms in providing protection from STDs, including HIV (31,32). Although female condoms are costly compared with male condoms, sex partners should consider using a female condom when a male condom cannot be used properly. The female condom also has been used for STDs/HIV protection during receptive anal intercourse (33); although it might provide some protection in this setting, its efficacy remains unknown.
Cervical Diaphragms
In observational studies, diaphragm use has been demon- strated to protect against cervical gonorrhea, chlamydia, and trichomoniasis (34). A recent trial examined the effect of use of a diaphragm plus polycarbophil (Replens) lubricant on HIV acquisition in women in Africa relative to male condom use alone. The study revealed that neither the diaphragm nor the lubricant gel provided additional protective effect when compared with the use of condoms alone (35). Likewise, no difference by study arm in the rate of acquisition of chlamydia or gonorrhea occurred; however, data from participants who reported following the protocol for the use of these products suggested that consistent use of the diaphragm plus gel might reduce acquisition of gonorrhea (36). Diaphragms should not be relied on as the sole source of protection against HIV infec- tion. Diaphragm and nonoxynol-9 (N-9) spermicide use have been associated with an increased risk for bacterial urinary-tract infections in women (37).
Topical Microbicides and Spermicides
Studies examining nonspecific topical microbicides for the prevention of HIV and STD have demonstrated that these products are ineffective (38,39). Studies of spermicides containing N-9 have demonstrated that they should not be recommended for STDs/HIV prevention (40), and more recent randomized controlled trials have failed to show a pro- tective effect against HIV acquisition for BufferGel (a vaginal buffering agent), Carraguard (a carrageenan derivative) (41), cellulose sulfate (an HIV entry inhibitor), (42) and SAVVY (1.0% C31G, a surfactant) (43,44). Initial results from a study in which participants used 0.5% PRO2000 vaginal gel (a synthetic polyanion polymer that blocks cellular entry of HIV) on a daily basis appeared promis- ing, reducing the rate of HIV acquisition by 30% relative to no gel (45). However, a recent randomized trial of approximately 9,000 women failed to show any protective effect (46).
Condoms and n-9 Vaginal Spermicides
Condoms lubricated with spermicides are no more effec- tive than other lubricated condoms in protecting against the transmission of HIV and other STDs (www.cdc.gov/condo- meffectiveness/latex.htm). Furthermore, frequent use of sper- micides containing N-9 has been associated with disruption of the genital epithelium, which might be associated with an increased risk for HIV transmission (40). Therefore, use of condoms lubricated with N-9 is not recommended for STD/ HIV prevention; in addition, spermicide-coated condoms cost more, have a shorter shelf-life than other lubricated condoms, and have been associated with urinary-tract infection in young women (37).
