An intricate web of social, cultural, economic and physiological factors make women more vulnerable to HIV infection than men. They are, for biological reasons, more likely to become infected upon exposure to HIV. Women in many cultures may also lack the power to control condom use or otherwise negotiate the terms of their sexual relations with men. In other words, women are frequently put at risk of HIV infection not by their own choices but by prevailing social norms and the behavior of partners.

For this reason, there is a serious need for HIV prevention tools that can be initiated or controlled by women, such as preventive AIDS vaccines and microbicides. If such tools were available, women would no longer depend on male cooperation to protect themselves from HIV infection. They would, for instance, be able to use a vaccine or microbicide with or without their partners’ awareness or cooperation.

Further, adolescent girls, who are particularly vulnerable to HIV infection, could potentially be vaccinated as pre-adolescents before they become sexually active or engage in other risk behaviors.