The relationship of fetal heart rate (FHR) to neonatal heart rate (NHR) was examined in 81 uncomplicated term (>37 weeks) deliveries. Average base line FHR during the 30 minutes before delivery was compared with baseline NHR obtained on the same infants at 5 and 10 minutes, 1, 12, and 24 hours after delivery. Fetal status and gestational age were determined by Apgar score and Dubowitz examination. Five minutes following delivery, a 30 percent increase in NHR over FHR baseline was noted in 75 neonates (93%). The NHR returned to FHR within 12 to 24 hours. There were no differences in heart rate patterns of neonates, whether delivered vaginally or by cesarean section. Neonates delivered spontaneously or with forceps also had comparable HR patterns. It appears that the events of labor and delivery are not responsible for the increased heart rate observed in the early newborn.
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