In malaria-endemic regions, insecticide-treated nets and intermittent preventive therapy (IPT)—single-dose preventive therapy with sulfadoxine-pyrimethamine—are key components of malaria control in pregnancy. However, increasing resistance to sulfadoxine-pyrimethamine raises concerns about the efficacy of this strategy. In a systematic review of clinical trials of sulfadoxine-pyrimethamine in Africa, ter Kuile and colleagues assessed the efficacy of IPT with sulfadoxine-pyrimethamine on placental and peripheral malaria, birth weight, low birth weight, and maternal anemia (hemoglobin level) in relation to regional sulfadoxine-pyrimethamine resistance. The authors found that in areas of Africa with sulfadoxine-pyrimethamine resistance as high as 39%, 1 dose of IPT sulfadoxine-pyrimethamine given in trimesters 2 and 3 provided substantial benefit to HIV-negative women. Among HIV-positive women, more frequent dosing appeared necessary.