OBJECTIVES: To determine the association of Bacterial vaginosis (BV) and other sexually transmissible infections (STIs) with HIV prevalence among pregnant women in Jos, Nigeria. METHODS: This was a cross- sectional study of pregnant women who participated in the Prevention of Mother-to-Child Transmission of HIV program of the AIDS Prevention Initiative in Nigeria, between April 2002 and July 2004, at the Jos University Teaching Hospital in Jos, Nigeria. Blood, high vaginal and endocervical samples were obtained for diagnosis of HIV, BV and other STIs. Data were analyzed for prevalence of HIV, BV and other STIs. Univariate and multivariate logistic regression models generated unadjusted and adjusted odds ratios (OR) as well as 95% confidence intervals (CI) of the association of BV and other STIs with HIV prevalence. P value <0.05 was considered statistically significant. RESULTS: A total of 4,046 pregnant women were studied and 97.6% (3,950/4,046) had complete laboratory records for analysis. The prevalence of HIV was 8.2% (CI: 7.4-9.1); BV 11.9% (CI: 10.9-12.9); Candida 10.7% (CI: 9.7-11.7); mixed infection of BV and Candida 2.8% (CI: 2.3-3.4); Trichomonads 0.6% (CI: 0.3-0.8) and syphilis 0.35% (0.16-0.54). BV, Candida, mixed BV and Candida; and Trichomonads were independently associated with HIV infection [adjusted OR (95% CI), 2.9 (CI: 2.2-3.9); 2.0 (CI: 1.5-2.9); 3.4 (CI: 2.0-5.6), and 3.3 (CI: 1.1-9.7) respectively]. CONCLUSION: HIV prevalence is higher among pregnant women who have BV, Candida and Trichomonads vaginal infections compared with women who have no evidence of infection. The practice of routine screening for BV and other STIs among pregnant women as a strategy for identifying women at risk for prevalent HIV infection should be sustained/ encouraged and the syndromic management of STIs should be integrated into all antenatal care management protocols in antenatal clinics in order to curb the epidemic of heterosexual HIV transmission.