Impact of Malaria in Pregnancy on Risk of Malaria in Young Children: Systematic Review and Meta-Analyses

Background: The impact of prenatal exposure to Plasmodium falciparum on young children’s susceptibility to malaria has not been well characterized. Our aim was to quantify the risk of acquiring malaria among progeny of women with malaria during pregnancy. Methods: We searched MEDLINE, EMBASE, CINAHL, and the Cochrane Library for eligible prospective studies published through August 28, 2017. Thesaurus search terms included “malaria AND pregnancy AND (child OR infant)”. The primary predictor was malaria during pregnancy defined as placental malaria, maternal parasitemia, maternal clinical malaria, or pregnancy-associated malaria. Primary outcomes were parasitemia or clinically defined malaria of young children. Infection with P. falciparum was confirmed with a positive blood smear or rapid diagnostic test. We performed meta-analyses to pool adjusted risk estimates (odds ratio [aOR] or hazard ratio [aHR]) using a random effects model. Findings: Nineteen of 2053 eligible studies met inclusion criteria for the systemic review. Eleven of these studies were quantitative and were included in the meta-analyses. The pooled aOR or aHR of malaria during pregnancy for detection of parasitemia in young children were 1·94 [95% confidence interval (CI), 0·93-4·07; p=0·08] and 1·46 (95% CI, 1·07-2·00; p<0·001), respectively. The pooled aOR or aHR for clinically defined malaria in young children were 2·82 (95% CI, 1·82-4·38; p<0·001) and 1·31 (95% CI, 0·96-1·79; p=0·09), respectively. Interpretation: Our results confirmed that malaria during pregnancy significantly increases the overall risk of malaria in young children, and emphasize the urgent need to implement safe and highly effective strategies to prevent malaria during pregnancy. Funding Statement: This work was supported by the COBRE for Reproductive Health at Women & Infants Hospital of Rhode Island/NIGMS P20GM121298-01. An NIH/NIAID award to ICM (K08AI100997) supported this work. Declaration of Interests: The authors declare no competing interests. Ethics Approval Statement: The authors performed a systematic review according to the guidelines of PRISMA and MOOSE.