Effect of maternal alcohol consumption and infant ADH2*3 on birthweight, gestation age, and risk for congenital heart defects

Abstract

This study was undertaken to determine the effect of maternal alcohol consumption, the ADH2*3 allele in the infant, and a combination of both factors on adverse birth outcomes in a population of 258 case and 973 control infants. The ADH2*3 allele is associated with faster alcohol clearance in African-American adults and faster retinoic acid synthesis in vitro. Cases were defined as Maryland infants born with atrial septal defect (ASD) or pulmonary valve stenosis (PVS) heart defects during 1981-89. Controls were infants born in Maryland over the same time period free of congenital defects at birth. Study infants were genotyped for the ADH2*3 allele by a PCR-based methodology using infant bloodspots as a source of DNA. Maternal consumption of a maximum of 3 or more drinks per occasion in the 3rd trimester of pregnancy was associated with a negative trend for birthweight, particularly for infants whose mothers reported drinking throughout pregnancy. Frequency of alcohol consumption (<once/week, once/week, or daily) was not a statistically significant predictor of birthweight or gestation age in our population. The ADH2*3 allele was not a significant factor for decreased birthweight or gestation age in African-American infants. Regression coefficients for the effect of maternal alcohol consumption of a maximum of 1-2 drinks per occasion on these endpoints were not discernibly different when stratified by infant ADH2*3 status. Neither maternal alcohol consumption nor the presence of the ADH2*3 allele in the infant were strong risk factors for PVS or ASD in our population. Odds ratios for the effect of maternal alcohol consumption and PVS or ASD did not differ when stratified by the presence of the ADH2*3 allele. Most mothers in this study that reported alcohol consumption during pregnancy reported infrequent consumption (<once/week) and light drinking (maximum of 1-2 drinks per occasion). Therefore, we cannot rule out the possibility that heavy maternal alcohol consumption may be an important factor for decreased gestation age and increased risk for ASD or PVS, but that our study did not have adequate statistical power to detect these associations.