Complement activation, placental malaria infection, and birth weight in areas characterized by unstable malaria transmission in central Sudan

Background: The pathogenesis of malaria during pregnancy is not completely understood. There are few published data on complement activation and malaria during pregnancy. This study aimed to investigate complement activation and malaria during pregnancy, and their association with hemoglobin and birth weight. Methods: A cross-sectional study was conducted at Medani, Sudan. Soluble terminal complement complex (TCC) levels were measured using ELISA in maternal and cord blood samples from 126 parturient women. Results: There were no Plasmodium falciparum-positive blood films from maternal peripheral blood, the placenta, or cord blood samples. Three (2.4%) and 22 (17.5%) of the placentas showed chronic and previous infection with histopathological examination, respectively, while 101 (80.2%) of them had no malaria infection. The mean [SD] of the maternal (22.4 [6.1] vs. 26.5 [3.5] ng/ml, P < 0.001) and cord blood (24.5 [4.5] vs. 26.8 [4.4] ng/ml, P = 0.024) TCC levels were significantly lower in cases of placental malaria infection (n = 25) than in those without placental malaria infection (n = 101). Linear regression showed that placental malaria infection was significantly associated with birth weight (-0.353 g, P = 0.013), but there were no associations between maternal and cord TCC levels and maternal hemoglobin, or between TCC levels and birth weight. Conclusion: Maternal and cord blood TCC levels are lower in women with placental malaria infection than in those without placental malaria infection.