Efficacy and safety of intrapartum electronic fetal monitoring: an update

Abstract

To compare the efficacy and safety of routine electronic fetal monitoring (EFM) of labor with intermittent auscultation, using the results of published randomized controlled trials (RCTs). We identified RCTs by searching the MED-LINE data base for the period 1966-1994, contacting experts, and reviewing published references. Our search identified 12 published RCTs addressing the efficacy and safety of EFM; no unpublished studies were found. The studies included 58,855 pregnant women and their 59,324 infants in both high- and low-risk pregnancies from ten clinical centers in the United States, Europe, Australia, and Africa. Data were abstracted, and their accuracy was confirmed independently. A single reviewer assessed study quality based on criteria developed by others for RCTs. Data reported from similar studies were used to calculate a combined risk estimate for each of nine outcomes. Overall, a statistically significant decrease was associated with routine EFM for a 1-minute Apgar score less than 4 (relative risk [RR] 0.82, 95% confidence interval [CI] 0.65-0.98) and neonatal seizures (RR 0.5, 95% CI 0.30-0.82). The protective effect of EFM for a 1-minute Apgar score less than 4 was apparent only in the non-United States studies, and the protective effect for neonatal seizures was evident only in studies with high-quality scores. No significant differences were observed in 1-minute Apgar scores less than 7, rate of admissions to neonatal intensive care units, and perinatal death. An increase associated with the use of EFM was observed in the rate of cesarean delivery (RR 1.33, 95% CI 1.08-1.59) and total operative delivery (RR 1.23, 95% CI 1.15-1.31). Risk of cesarean delivery was greatest in low-risk pregnancies. The only clinically significant benefit from the use of routine EFM was in the reduction of neonatal seizures. Because of the increase in cesarean and operative vaginal deliveries, the long-term benefit of this reduction must be evaluated in the decision reached jointly by the pregnant woman and her clinician to use EFM or intermittent auscultation during labor.