Maternal Continuing Folic Acid Supplementation after the First Trimester of Pregnancy Increased the Risk of Large-for-Gestational-Age Birth: A Population-Based Birth Cohort Study

Supplementation with folic acid (FA) was proven to prevent neural tube defects (NTDs) and was recommended worldwide before and during early pregnancy. However, much less is known regarding the role of FA after the 12th gestational week (GW). This study aimed to investigate the related effects of continued FA supplementation after the first trimester of pregnancy on fetal growth. The study subjects came from the Ma’anshan-Anhui Birth Cohort Study (MABC) that recruited 3474 pregnant women from the city of Ma’anshan in Anhui Province in China during the period of May 2013 to September 2014. The information on use of vitamin and mineral supplements was recorded in different periods (the first/second/third trimester of pregnancy). Small-for-gestational-age (SGA) births were live-born infants that were