Bendectin (Debendox) as a risk factor for pyloric stenosis.

The maternal use of Bendectin (Debendox) in the first trimester of pregnancy was examined in a case-control (n = 1,427 and 3,001, respectively) study of malformed infants whose mothers were interviewed between 1974 and 1976. Mothers of infants with congenital malformation showed an increased likelihood (odds ratio = 1.40) of having used Bendectin, with a stronger association of Bendectin with birth defects for mothers who also smoked (odds ratio = 2.91). A significant association was observed between the occurrence of pyloric stenosis in the infant and exposure to Bendectin in utero (odds ratio = 4.33). When maternal sociodemographic factors, including smoking, and smoking alone, were controlled, the association between Bendectin and pyloric stenosis was further increased (odds ratio = 4.63 and 5.24, respectively). Except for a possible association of Bendectin with heart valve anomalies (odds ratio = 2.99), we were unable to document other significantly increased risks for congenital malformations.