PARENTAL CIGARETTE-SMOKING AND RISK FOR CONGENITAL-ANOMALIES OF THE HEART, NEURAL-TUBE, OR LIMB

Risks for selected congenital anomalies from parental smoking were inv estigated in a case-control study in California. Mothers of 207 infant s with conotruncal heart defects, 264 infants with neural tube defects , 178 infants with limb deficiencies, and 481 live born control infant s delivered in 1987-1988 were interviewed by telephone. Modestly eleva ted risks were observed for conotruncal heart defects and limb deficie ncies, associated primarily with both parents smoking. An odds ratio o f 1.9 (95 percent confidence interval 1.2-3.1) was observed for conotr uncal heart defects and an odds ratio of 1.7 (95% confidence interval 0.96-2.9) for limb deficiencies when both parents smoked compared to n either parent smoking. We did not observe increased risks associated w ith maternal smoking in the absence of paternal smoking, although an i ncreased risk associated with paternal smoking in the absence of mater nal smoking was observed for limb deficiencies in off-spring. For cono truncal defects, the risks associated with parental smoking differed a mong race/ethnic groups. Parental smoking was not associated with incr eased risks for neural tube defects. Observed risks did not change sub stantially when adjusted for maternal vitamin use, alcohol use, and gr avidity. Some heterogeneity in risk was observed for phenotypic case s ubgroups, but data were too sparse to draw firm inferences. (C) 1996 W iley-Liss, inc.