Effect of maternal alcohol consumption during the pre-pregnancy/early-pregnancy period on congenital heart disease: A prospective cohort study in Central China

Evidence of associations between maternal alcohol consumption and congenital heart disease (CHD) are mixed. Previous studies have been potentially biased due to recall bias or unmeasured confounding. This study aimed to examine the association of maternal alcohol consumption in 3 months before pregnancy and in early pregnancy with risks of offspring congenital heart disease (CHD) and its seven common subtypes. A prospective cohort study was conducted in Central China. From 03/13/2013 to 12/31/2019, a total of 44,048 pregnant women with singleton pregnancies at 8–14 gestational weeks were included and followed to 3 months postpartum. 564 births were diagnosed with CHD at the end of follow-up. Multivariable modified Poisson regression models were used to estimate the relative risks (RRs) of CHD in offspring exposed to maternal alcohol consumption during the pre-pregnancy and early-pregnancy period, adjusting for confounders identified by directed acyclic graphs. In the multivariable analyses, increased risks of CHDs were found in offspring exposed to maternal alcohol consumption both in 3 months before pregnancy (adjusted-RR:3.14; 95% confidence intervals[CIs]:2.30–4.28) and in early pregnancy (adjusted-RR:1.86; 95%CIs:1.13–3.05). More specifically, the offspring exposed to maternal alcohol consumption in 3 months before pregnancy had the highest increased risk of Tetralogy of Fallot (adjusted-RR:8.62; 95%CIs:3.61–20.61). These findings persisted in analyses that were further adjusted for the other behavior variables other than the characteristic being assessed, and were also confirmed by sensitivity analyses. Our study supports the need for continued efforts for public health messages surrounding the potential risks of alcohol consumption prior to or during pregnancy.