Perinatal data on 76 twin pregnancies demonstrated a significantly (P less than 0.01) lower Apgar score and acidemia in the umbilical artery for the second twin. Factors such as female sex, prematurity, low birth-weight and instrumental delivery accounted for this difference (P less than 0.05 or P less than 0.01). These differences were not found for parity, pregnancy complications and time interval. Using electronic fetal surveillance, expert personnel and rapid resuscitation the neonatal depression could be reversed rapidly, as demonstrated in capillary heel blood. Perinatal mortality was 2-3-times higher than for singletons but perinatal morbidity fell in the range for singletons and was not due to the short-lasting asphyxia during birth.