The seroprevalence of maternal and neonatal hepatitis B surface antigen (HBsAg) was determined prospectively through unlinked anonymous testing of volunteers at delivery at the University of Benin Teaching Hospital, Benin City, Nigeria. Six hundred and forty (320 mother-cord blood pairs) samples were assayed for HBsAg using hepatitis B latex test kit (Biotech Laboratory Ltd, UK). Repeatedly reactive samples were confirmed by the use of ELISA kit (Wellcome Laboratory, UK). None of these women had had a blood transfusion or hepatitis B vaccination in the past, and none was an intravenous drug abuser. The maternal seroprevalence was 2.19%. This means one of every 45 pregnant women was a carrier of the antigen. The neonatal seroprevalence and the vertical transmission rate were 0.96% and 42.86%, respectively. The endemicity of this occasionally fatal disease is thus being propagated. We advocate universal free screening and immunisation of our pregnant women and their infants as part of the antenatal and childhood immunization programmes. Healthcare providers should be vaccinated routinely.