Preventing disease by protecting the cervix: the unexplored promise of internal vaginal barrier devices.

Abstract

In the absence of an effective vaccine or treatment contraceptive methods capable of preventing sexual transmission of HIV as well as other sexually transmitted diseases (STDs) are vital for protecting the health of a woman. As such vaginal microbicides may provide such alternative to women-controlled methods. Although many of these new microbicides show robust activity against HIV and other STD pathogens and some also appear to be less toxic achieving reliable protection with microbicides remains a significant challenge. Hence in this paper the authors contend that the likelihood of success of such products could be greatly increased by combining microbicide with an internal barrier that protects the cervix. Like condoms these devices (diaphragms caps and other novel designs) create a physical barrier that covers the cervix. Yet because they are worn completely inside the vagina they avoid the obtrusiveness that limits the acceptability of male and female condoms. Moreover microbicide should not only be applied on the cervical side as has been traditional for contraceptive use but also on the vaginal side of the device to mix directly with semen and help protect the vaginal epithelium. Nevertheless in spite of its potential efficacy as with any new method of prevention its efficacy will only be as good as its use which is ultimately determined by acceptability.