BACKGROUND The heterogeneity in detection rates of Human immunodeficiency virus, (HIV), Human T lymphotropic virus (HTLV) and Hepatitis B and C infections among pregnant women and the continuous exposure to risk factors limits the adoption of preventive and control actions. OBJECTIVE To evaluate the HIV, HTLV, Hepatitis B and C seroprevalence rates, and associated risk factors in parturient women in Salvador, Brazil. METHODS This was a cross-sectional study in 2099 parturient women attended in two public maternity hospitals in Salvador, Brazil. One blood sample was drawn for serological screening and socio-demographic, obstetric and clinical data were collected. RESULTS HIV seroprevalence rate was 1.5% (of which 0.6% were new cases); seroprevalence rates for HTLV, HBV, and HCV were 0.4%, 0.4%, and 0.1%, respectively. Univariate analysis showed a significant association between socio-demographic and behavioral factors with retroviral infections, while viral hepatitis was mainly associated with parenteral exposure. In a multivariate analysis, multiple sexual partners (OR 3.3; 95% CI: 1.1-9.2), history of sexual/domestic violence (OR 2.8; 95% CI: 1.1-6.9), syphilis co-infection (OR 2.6; 95% CI: 1.0-6.9), use of alcohol or drugs (OR 2.5; 95% CI: 1.2-5.5), and low schooling level (OR 2.3; 95% CI: 1.1-4.9) were independent risk factors for HIV infection. History of stillbirth and low birth weight infants was significantly associated with HTLV positive status, showing a negative impact on gestation. CONCLUSIONS The seroprevalence rates for HIV, HCV, HBV, and HTLV were similar to that found in previous studies in other Brazilian regions. The high individual, socioeconomic, and social vulnerability detected in seropositive parturient women indicates the need to improve coverage and effectiveveness of STDs control with prevention, detection and monitoring strategies, focusing in pregnant women exposed to high biopsychosocial risk.