Low maternal alcohol consumption during pregnancy and oral clefts in offspring: the Slone Birth Defects Study

Abstract

Background: The association between maternal alcohol consumption during pregnancy and oral clefts in offspring remains unclear. We studied this relation in a case-control surveillance study of birth defects.

Methods: From 1983 to 1997, we recruited 5956 study subjects from greater Boston, Philadelphia, Toronto, and parts of Iowa. The cases were liveborn infants with cleft palate alone (CP; n = 205), cleft lip and palate (CLP; n = 383), cleft lip alone (CL; n = 259), or Pierre-Robin sequence (n = 65). The controls (n = 4272) were infants who had no oral clefts but had one or more of the following defects: malformations of the digestive tract, reproductive organs, abdominal wall, and respiratory tract; chromosomal anomalies; inguinal hernia; tumors; and Mendelian inherited disorders. Based on maternal reports of alcohol consumption during the first 4 months of pregnancy, we derived average weekly consumption, average number of drinks per drinking day, and the maximum number of drinks consumed in a given day. The mothers also provided data on potential confounding or modifying variables, such as vitamin supplement use.

Results: There was no relation between maternal alcohol consumption during pregnancy and CL or CP. The odds ratios (ORs) for cleft lip with or without palate (CL/P) were 1.0, 1.1, and 0.9 in women who consumed <1.0, 1.0-2.9, and 3.0 + drinks per week, respectively. These findings did not change when we considered possible modifying effects of vitamin supplement use.

Conclusions: Our findings do not support an association between oral clefts and a low level of alcohol consumption.