OBJECTIVES: To determine risk factors for HIV among pregnant women (N = 2657) receiving antenatal services in Jos, Plateau state, Nigeria. METHODS: Information about potential risk factors was obtained at interview. Biological samples were collected for detection of HIV and other sexually transmitted infections (STIs). RESULTS: The prevalence of HIV was 8.2%. Women aged 20-29 years had more than 4-fold increased risk of HIV. Women of Catholic (adjusted odds ratio (AOR) = 1.72, 95% CI = 1.01-2.95) and Pentecostal (AOR = 2.57, 95% CI = 1.46-4.52) denominations were more likely to be HIV-infected when compared to Moslem women. The risk of HIV was also increased among women with multiple marriages and in women married to a banker/accountant. Other predictors of HIV were having a husband with other partners, perceived risk of HIV, STIs, candidiasis and bacterial vaginosis. CONCLUSIONS: Development of effective interventions, including behavioral change, expansion of perinatal HIV prevention services and STI control, should be given the highest priority.