To assess the ability of antenatal care to manage hypertension in pregnancy, a cross-sectional study involving 379 pregnant women was conducted in 16 randomly selected antenatal clinics in Rufiji district of Tanzania. We observed necessary structural availability, provider client interaction, interviewed women attending antenatal clinics, and measured their blood pressure. Measurements made by observers and health workers were compared. One third of the women were not checked for hypertension and health workers detected only four out of twelve women with elevated blood pressure. There was disagreement in diagnosis of blood pressure as measured by health workers and observers. Only one woman with elevated blood pressure was managed appropriately. The low quality of screening and management of hypertension in pregnancy makes it less realistic to expect any impact of antenatal care programme in reducing morbidity or mortality due to hypertension in pregnancy.