Background: À significant number of pregnant women in Brazil are unaware of their HIV serostatus because of lack of prenatal care, lack of testing or unavailability of results. We evaluated the feasibility of rapid HIV testing during the peripartum period followed by interventions. Methods: Pregnant women with unknown HIV status were offered rapid HIV testing from 04/2000 to 12/2001 at hospitals in Rio de Janeiro (RJ), Porto Alegre (POA) and Belo Horizonte (BH). HIV seropositivity was determined by a rapid HIV test (Determine 1/2) and confirmed by HIV EIA/ WB. Patients identified as HIV+ prior to delivery reccived TV ZDV during labor. Tnfants received oral ZDV initiated before 48 hours of life until six weeks of age. HIV-exposed infants ‘had HIV DNA PCR performed at birth, 1 and 3 months of age Results: 4901 women accepted HIV rapid testing during the peripartum period. 121 previously undiagnosed HIV-infected women were identified. The overall seroprevalence rate was 2.5%. HIV rates varied by city, being 1.4% (48/3459) in RY, 7.2% (71/992) in POA, and 0.4% (2/450) in BH. 109 HIV-exposcd infants had HIV DNA PCR performed at birth. There were 4 stillbirths and one infant death. 7/109 infants were HIV-infected at birth, 4/42 in Rio, 2/66 in POA, and 1/1 in BH (in utero transmission rate: 6.4%). All infants started ZDV within 48 hours of life, and no mothers breastfed. Follow-up DNA PCRs are pending Conclusions: HTV rapid testing was feasible and acceptable. Seroprevalence rates were higher in the south of the country (7.2%) as compared to the southeastern region (1.4% and 0.4%). Stillbirths and infant death rates were high among exposed infants (4%; 5/121). 6.4% of infants were infected at birth. Women with no prenatal care are at high risk for HIV infection and adverse infant outcomes. HIV screening during pregnancy and in the peripartum period coupled with enhanced delivery of prenatal care should be a priority, particularly in the south of Brazil.