摘要:Kawasaki disease (KD) is an acute systemic vasculitis that mainly affects infants and young children. The etiology of KD has been discussed for several decades; however, no reproducible risk factors have yet been proven. We used the Japan Environment and Children’s Study data to explore the association between the causal effects of exposure during the fetal and neonatal periods and KD onset. The Japan Environment and Children’s Study, a nationwide birth cohort study, has followed approximately 100,000 children since 2011. We obtained data on exposures and outcomes from the first trimester to 12 months after birth. Finally, we included 90,486 children who were followed for 12 months. Among them, 343 children developed KD. Multivariate logistic regression revealed that insufficient intake of folic acid during pregnancy (odds ratio [OR