vagina, which can increase vulnerability to HIV infection transmitted during vaginal intercourse (Van Damme, 2000). Furthermore, animal research has shown that N-9 can damage the cells lining the rectum, thus providing a portal of entry for HIV and other STI pathogens (Workowski et al., 2010). The CDC recommends against use of condoms lubricated with N-9 spermicide.

Available barrier methods for preventing STI transmission are often disadvanta­geous to women because they are either male controlled (the male condom) or require male cooperation (the female condom). Consequently, researchers are actively pursuing methods for STI prevention that can be controlled solely by women. These efforts are described in the following paragraphs.