Birth weights of 843 children with congenital heart disease (CHD) were compared to the respective data of a normal West German population. On average, the CHD group had significantly lower birth weights, but the weight deficit was far less pronounced than in previous studies. The decrease in birth weight was distinct only in children with tetralogy of Fallot and atrial septal defect. Compared to normal newborns, patients with CHD were more often small for gestational age (15.0%) or had a low (less than 2500 g) birth weight (8.6%). The prevalence of prematurity was not increased. Extracardiac malformations were not significantly more common in CHD patients, who were small for gestational age, than in CHD patients with normal birth weight.