Malaria is the most important human parasitic disease and is responsible of high morbidity and mortality in resource-poor countries. Pregnant women, who are a high-risk group, are almost always excluded from clinical trials; thus, the investigators lack sufficient information on the safety and efficacy of most antimalarials in pregnancy. The recommendation of the World Health Organization to use artemisinin combination therapy (ACT) in the 2nd and 3rd trimester is already implemented in several African countries, however documentation of their efficacy and safety in pregnancy is still limited. Thus, the investigators propose to evaluate the efficacy and safety of 4 ACT(artemether-lumefantrine, amodiaquine-artesunate, mefloquine-artesunate and dihydroartemisinin-piperaquine), when used to treat pregnant women with P. falciparum malaria; the results will help to recommend the optimal therapy for this high-risk group in Africa.