The outcomes of cardiovascular operations during pregnancy, at delivery, and post partum were reviewed from published material in the period 1984-1996. Surgery during pregnancy resulted in fetal-neonatal morbidity and mortality of 9% and 30%, respectively, and in maternal morbidity and mortality of 24% and 6%, respectively. Duration of pregnancy at surgery and duration and temperature of cardiopulmonary bypass did not influence fetal-neonatal outcome. Maternal complications and mortality of surgery immediately after delivery were 29% and 12%, respectively, and for surgery performed with a postpartum interval the respective rates were 38% and 14%. Hospitalization after week 27 of gestation and extreme emergency contributed significantly to poor maternal outcome. Maternal deaths were reported in 9% of valvular procedures and in 22% of aortic or arterial dissection repairs and pulmonary embolectomies. Fetal-neonatal risks of maternal surgery during pregnancy are high and unpredictable. Maternal risks of cardiovascular procedures during pregnancy are moderate, significantly increase if an operation is performed at or after delivery, and, overall, should be considered as higher than those in nonpregnant cardiovascular surgical patients.