Does light-to-moderate alcohol consumption during pregnancy increase the risk for renal anomalies among offspring?

OBJECTIVE To determine the association between light-to-moderate prenatal alcohol exposure and congenital renal anomalies. METHODS Data from the population-based Atlanta Birth Defects Case-Control Study were used to examine the association between selected renal anomalies and self-reported maternal alcohol consumption during the period from 1 month before through 3 months after conception. Case infants were ascertained by a population-based birth defects registry with active case ascertainment; the case group consisted of 158 infants, born during 1968 through 1980 to metropolitan Atlanta residents, in whom these renal anomalies had been diagnosed. Two control groups were used. One had 3029 infants without birth defects, and the other had 4633 infants with birth defects exclusive of the urinary tract who were born during the same period. RESULTS Overall, there was a moderate association between renal anomalies and moderate prenatal alcohol exposure (odds ratio, 1.5; 95% confidence interval, 1.0 to 2.3). When the renal anomalies were subclassified, moderate prenatal alcohol exposure was significantly associated only with renal agenesis or hypoplasia (odds ratio, 2.5; 95% confidence interval, 1.2 to 5.1), and within this group only infants with bilateral defects and other major anomalies in addition to renal agenesis or hypoplasia had significantly elevated risks. There were no significant associations between reported light consumption and any category of the selected renal anomalies. No conclusions could be reached for reported heavy consumption because of sparse data. Adjustments for potential confounding factors did not alter these results. CONCLUSION This study suggests that moderate alcohol consumption during pregnancy may increase a woman's risk of giving birth to a child with renal agenesis or hypoplasia.