for our subsequent regression analyses. Specifically, we compared three levels of maternal
alcohol consumption per week during pregnancy (< 1 drink per week, 1–3 drinks per week,
and 4 or more drinks per week) to no alcohol use, the control variable. Hence, the
remaining categories (4–6 drinks per week, 7–13, 14–19, and 20 or more) were combined to create a relatively heavy consumption category of 4 or more drinks per week.