Background Previous data suggest that women who have sex with women and men (WSWM) have the highest STI risk compared to other female sexual behaviour groups. We compared risk behaviours and STI rates among women who have sex with women (WSW), WSWM, women with a single male partner (WSM), and women with multiple male partners. We hypothesised a continuum of STI risk with WSW having the lowest risk, followed by WSM with one partner, WSM with multiple partners, and WSWM.

Methods A secondary analysis of data from two studies of African American women evaluated at a Birmingham, Alabama STD clinic was performed. One study included exclusive WSW (n = 78) and WSWM (n = 85) during the preceding year while the other evaluated WSM (n = 91 with one male partner and n = 78 with multiple male partners) during this timeframe. All participants completed a questionnaire and were tested for STIs.

Results Groups did not differ by education, employment status, or recent alcohol/drug use. WSWM and WSM with multiple partners were more likely to report prior incarceration, transactional sex, and new/casual partner (s) within the past month. Rates of chlamydia and gonorrhoea were significantly different across groups with WSM more likely to have chlamydia and WSWM and WSM more likely to have gonorrhoea. In contrast, WSW and WSWM were more likely to have trichomoniasis than WSM. With the exception of WSW (25%), HSV-2 seroprevalence was high (>50%) among all groups. WSWM and WSM with multiple partners were more likely to report condom use at their last sexual encounter than WSM with single male partners and WSW.

Conclusion Among women attending an STD clinic, STIs were common in all groups however prevalence appears to vary in association with partner gender and number. Even in STD clinics, partner gender and number are important factors to consider in sexual health counselling.

Disclosure of interest statement Funding for original research was received from a Development Award from the American Sexually Transmitted Disease Association. No pharmaceutical grants were received in the development of this study.