Our study adds at least two important results to the existing literature: women carrying the rs1229984 A allele are less likely to report episodes of binge drinking during pregnancy and they are more likely to report quitting alcohol during the first trimester. The first finding is in line with previous evidence, and extends this to the extremely sensitive time of pregnancy, when alcohol consumption has several potential adverse effects on the fetus (10). The association with drinking cessation is an entirely new result. Whether metabolic changes occurring in pregnancy interact with the effect of the variant, or whether the increased odds of quitting alcohol are due to residual confounding by usual (pre-pregnancy) alcohol intake, we cannot tell.
