The impact of malaria during pregnancy varies greatly according to the intensity of transmission. Severe acute complications including cerebral malaria or materno-fetal death seem to be confined to areas of unstable transmission where malaria is uncommon except during epidemics. In areas of stable endemicity, the main consequences are maternal anemia and intra-uterine growth retardation resulting in low birthweight (LBW) particularly after first pregnancies. Recent studies have demonstrated that frequency and severity of placental malaria are greater in pregnant women with concurrent HIV infection. Since 1964 several controlled trials have been conducted to evaluate chemoprophylaxis in pregnant women mainly in tropical Africa where malaria transmission is stable. Findings have usually demonstrated an increase in mean birthweight after prophylaxis especially among primigravidae. Prophylaxis also had beneficial effects on anemia. Another finding of these trials was that prevention is less effective for women with HIV co-infection and that higher doses may therefore be required in such cases. In our opinion prophylaxis should be actively promoted as a routine public health measure for pregnant women in endemic areas. Current recommendations call for the use of a sulfadoxine-pyrimethamine twice or three times during pregnancy in antenatal clinics. This combination is more effective as a result of strong resistance of parasites to chloroquine. High cost and possible adverse effects in pregnant women prohibit routine use of mefloquine in developing countries. Integration of malaria prophylaxis into antenatal care services with nutrition and immunization measures should enhance the overall efficacy of prevention in outlying clinical facilities. Recent identification of molecular receptors involved in the cytoadherence of parasitized red blood cells to the placenta may lead to the development of new therapeutic or vaccinal approaches for pregnant women.