About 30% of women in the study reported consuming alcohol— predominantly wine — during their first month of pregnancy. ... Overall alcohol exposure levels among women who reported drinking were relatively low, with a median level of approximately one drink per week in the first month of pregnancy.
The team found that for those women who drank low to moderate amounts of alcohol in early pregnancy, there was a reduced likelihood of low birth weight, short birth length, and small head circumference, which are all hallmarks of FAS. Drinking later in pregnancy during the third trimester was associated with lower risk for low birth weight and preterm delivery.
--Karen Peart, Yale News, on the usual U-shape alcohol harm curve showing up again