The relationship between cigarette smoking and alcohol consumption behavior during pregnancy was examined in a select group of Danish women and their spouses. Five-hundred consecutive women who had uncomplicated pregnancies and delivered full-term babies were interviewed 3+ days postpartum. Information was collected about smoking and drinking behavior of all household members during pregnancy. We found (1) a high percentage of Danish women (70%) and their spouses (80%) consume alcohol during pregnancy, and (2) a significant correlation between maternal and paternal smoking (r = .25, P .0001) and maternal and paternal drinking (r = .35, P .0001). These data suggest that even though the potential dangers of cigarette smoking and alcohol consumption during pregnancy have been well publicized, there is still a high percentage of women who participate in such behaviors. There may also exist an important role for the father in affecting these two behaviors and therefore indirectly affecting fetal development.