NONSTRESSED FETAL HEART-RATE MONITORING IN THE ANTEPARTUM PERIOD (REPRINTED FROM AM-J-OBSTET-GYNECOL, VOL 126, PG 699-706, 1976)

The role of nonstressed monitoring of the fetal heart rate (HR) is det ermining fetal well-being during the antepartum period was assessed in 125 high-risk patients. Observations on HR, variability, and HR respo nse to fetal movement (FM) and uterine contractions (UC) over a 30 min ute period were made with an external microphone and tocotransducer. A total of 625 tests were performed; the earliest gestation tested was 28 weeks, and the latest tons 46 weeks. A reactive pattern (variabilit y > 6 b.p.m. and accelerations with FM) appears to be a reliable indic ator of fetal well-being. All the 51 fetuses exhibiting this pattern s urvived. This group also had the lowest incidence of neonatal complica tions. On the other hand, of the babies who failed to show variability > 6 b.p.m. or accelerations with FM (nonreactive pattern), 40 per cen t died in the perinatal period. Thirty-five patients showed features o f both a reactive and nonreactive pattern (combined pattern). Poor out come in this group was confined to those in whom the majority of the p attern was nonreactive. An undulating HR pattern with virtually absent variability (sinusoidal pattern) was found in 20 Rh-sensitized fetuse s, 50 per cent of whom died in the perinatal period. Bradycardia and t achycardia were not found to be reliable signs of fetal distress antep artum. Of the 12 fetuses who died during observation, six showed late deceleration with spontaneous UC but all showed diminished variability . The close correlation between nonstressed patterns and neonatal outc ome demonstrated by this preliminary study warrants further use of thi s technique for fetal evaluation.