Maternal prepregnancy body mass index, gestational weight gain, and allergic diseases in children: A systematic review and meta‐analysis

Summary Several studies have investigated a link between maternal preconception body mass index, gestational weight gain (GWG), and the risk of childhood allergic diseases, but the conclusions of these studies were inconsistent. This review aimed to evaluate the relationship based on existing studies. We eventually included 18 cohort studies. The findings indicated that both maternal preconception overweight or obesity increased the risk of childhood wheezing (overweight: risk ratio (RR) 1.09, 95% confidence interval (CI) 1.04–1.15; obesity: RR 1.24, 95% CI 1.12–1.38) and asthma (overweight: RR 1.18, 95% CI 1.05–1.32; obesity: RR 1.34, 95% CI 1.13–1.58), and the risk of childhood wheezing increased with continuous prepregnancy BMI changes (per 5 kg/m 2 increase) (RR 1.10, 95% CI 1.05–1.15). Preconception underweight may elevate the risk of childhood eczema ever (RR 1.05, 95% CI 1.02–1.09) and current eczema (RR 1.20, 95% CI 1.05–1.37), and preconception overweight may reduce the risk of childhood eczema ever (RR 0.98, 95% CI 0.96–0.99). No statistically significant association between GWG and the risk of allergic diseases in children was found. Preconception weight management is encouraged for the prevention of allergic diseases in children.