Maternal Anemia during pregnancy and infant low birth weight: A systematic review and Meta-analysis

BACKGROUND Infant low birth weight is one of the major problems in different societies. Different reports have provided different results regarding the relationship between maternal anemia and infant low birth weight in different months of pregnancy. OBJECTIVE The aim of this study was to determine the relationship between maternal anemia during pregnancy and infant low birth weight. MATERIALS AND METHODS This systematic review was conducted using related keywords in national (Sid, Iran.doc, Iran medex and Magiran) and international (PubMed, Science Direct, Cochrane, Medline, Web of Science, Scopus, Springer, Embase, Google scholar) databases. Relative risks and confidence intervals were extracted from each study. The results were combined using random-effects model for meta-analysis. The I2 index was also used to measure heterogeneity between the studies. RESULTS Overall, 17 studies with a total sample size of 245407 entered the final meta-analysis and demonstrated that the relative risk for maternal anemia in the first, second and third trimester of pregnancy were 1.26 (95% CI: 1.03-1.55), 0.97 (95% CI: 0.57-1.65), and 1.21 (95% CI: 0.84-1.76), respectively. The relationship between maternal anemia and infant low birth weight in the first trimester of pregnancy was significant. CONCLUSION Maternal anemia, especially during the first trimester of pregnancy, can be considered as a risk factor for pregnancy outcomes. Therefore, one needs to take the necessary steps to cure this disease in order to reduce the incidence of infant low birth weight.