Methods: In an epidemiologic study, parental alcohol consumption and smoking before, during, and after pregnancy were studied as possible risk factors for mental retardation in offspring. The parents of 306 mentally retarded children (cases) and 322 physically handicapped children (referents) were interviewed about their lifestyle habits from 3 months preconception to 6 months postnatal.
Results: Odds ratios with 95% confidence intervals were calculated as risk indicators. For fathers who smoked a pipe or cigars, an odds ratio of 2.4 (95% CI: 1.2-5.1) was observed. Maternal alcohol consumption was increased among the case mothers with risk ratios ranging from 1.7 (95% CI: 1.2-2.3) preconception to 1.4 (95% CI:1.0-2.0) during the fetal period. These risks were more pronounced for the mothers who consumed greater than or equal to 3 drinks/day once or twice a week.
Conclusions: This study suggests that paternal smoking and maternal alcohol consumption are risk factors for mental retardation in offspring.