Maternal caffeine consumption during pregnancy and risk of low birth weight: a dose–response meta-analysis of cohort studies

Earlier published studies on maternal caffeine intake during pregnancy in relation to the risk of low birth weight (LBW) (birth weight <2500 g) have indicated conflicting findings. Therefore, the present systematic review and meta-analysis was conducted to examine the association between maternal caffeine intake and risk of LBW.We searched for relevant articles published up to Jan 2021 through PubMed and Scopus. For this purpose, we used MESH (Medical Subject Heading) and non-MESH keywords. Cohort studies that considered maternal caffeine intake as the exposure variable and LBW as the main outcome variable were included in the systematic review. Finally, seven cohort studies were considered in this systematic review and meta-analysis.Combining seven effect sizes, we found a significant positive association between maternal caffeine intake and risk of LBW (RR: 1.70; 95% CI: 1.19-2.43). We also found that each additional 100-mg per day of maternal caffeine intake was significantly associated with an increased risk of LBW (RR: 1.12; 95% CI: 1.03-1.22; Pheterogeneity = 0.020). In addition, nonlinear dose-response analysis showed a significant relationship (Pnonlinearity < 0.001) between maternal caffeine intake and risk of LBW.In this systematic review and meta-analysis, we found a significant positive association between maternal caffeine intake and risk of LBW.