Do bisexual men play a significant role in the heterosexual spread of HIV?

To assess the potential role of bisexual men in the transmission of HIV to women.

The study population consisted of homosexual men participating in a longitudinal cohort study on HIV and AIDS in Amsterdam, the Netherlands, which started in 1984. Between April and November 1991, an additional questionnaire was administered concerning sexual behavior with both male and female partners in the last 6 months.

Of these men, 27% described their sexual preference as bisexual or heterosexual. In the last 6 months, 23 (3%) had heterosexual contacts. Vaginal intercourse was the sexual technique most practiced. Anal intercourse with a female partner was rare. Four heterosexual active HIV positive men always used condoms when having heterosexual contact (1 missing). Of the 18 heterosexually active HIV seronegative men, 12 did not use condoms consistently with their female partner(s). Two of these 12 men also had unprotected insertive anogenital intercourse with male partners, which conveys a small transmission risk in the window period in the case of a seroconversion.

Widespread transmission of HIV from these homosexual men in this study is not likely. However, the studied men are most probably not representative for homosexual men in Amsterdam, the Netherlands. Further study on the potential role that bisexual men play in the HIV transmission to women is therefore needed.