Clinical fetal monitoring. The usage and relationship to trends in cesarean delivery and perinatal mortality.

During the six years 1970--1975, 62,266 deliveries occurred at Women's Hospital, Los Angeles Country--University of Southern California Medical Center. Of these patients, 18,106 (29 per cent) were monitored, with an incidence of 18 per cent in 1970 which rose to 35 per cent in 1975. The patients were divided into monitored and unmonitored groups for comparison of cesarean section rates and various aspects of perinatal mortality. The overall cesarean section rate was 9.6 per cent with 2,830 cesareans performed in monitored patients (16 per cent) and 3,124 in those unmonitored, a 7 per cent incidence including repeat cesarean. The cesarean rate remained remarkably stable over the 6-year study period even though the monitoring incidence nearly doubled. From 1970 to 1975, the intrapartum death rate fell progressively in contrast to the incidence of antepartum fetal deaths, which remained unchanged. Overall, 50 per cent survival rate was achieved in the birth weight range of 1,200 grams. A particular group of perinatal patients who apparently benefited from intrapartum monitoring were those liveborns with birth weights of 1,500 grams or less. Over the study period, the neonatal mortality in monitored patients declined, whereas mortality in the neonates which were not monitored during labor remained high.