A nested case-control hospital study and a midwife-based community coh
ort study were conducted in Central Sudan during 1989 and 1990 to asse
ss the contribution of mesoendemic malaria to low birth weight. Malari
al infection was determined by maternal history, parasitology, and his
topathology. There were significant associations between a maternal hi
story of malaria and low birth weight in the hospital study (adjusted
odds ratio (OR) = 1.6, 95% confidence interval (Cl) 1.2-2.1) and the c
ommunity study (OR = 1.7, 95% Cl 1.3-2.3). Attributable risk percentag
es were high and were comparable in the hospital study (22.2%) and the
community study (24.5%). A significant trend of increased risk of low
birth weight was observed with increasing number of reported malaria
attacks, with attacks occurring earlier in pregnancy, and with higher
parasitemia. In addition, the risk of low birth weight associated with
malaria was higher among primiparous women than among multiparous wom
en. The mean birth weight of infants whose mothers had malaria during
pregnancy was significantly lower than the mean birth weight of infant
s whose mothers did not. Malaria treatment, chemoprophylaxis, and use
of insecticides decreased the risk of low birth weight and are recomme
nded as appropriate interventions. These measures should target primig
ravid women and should be initiated early in pregnancy.