Continuous electronic heart rate monitoring for fetal assessment during labor

Electronic fetal monitoring (EFM) is used in the management of labor and delivery in nearly three of four pregnancies in the United States. The apparent contradiction between the widespread use of EFM and expert recommendations to limit routine use indicates that a reassessment of this practice is warranted.

To compare the efficacy and safety of routine continuous EFM during labor with intermittent auscultation, using the results of published randomized controlled trials (RCTs).

We identified RCTs by searching MEDLINE and the register maintained by the Cochrane Pregnancy and Childbirth Group, and by contacting experts, and reviewing published references. Date of last search: January 2001.

Randomized controlled trials.

Data were abstracted by one of us, and their accuracy was confirmed independently by a second person. 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 eight outcomes.

Our search identified 13 published RCTs addressing the efficacy and safety of EFM; no unpublished studies were found. Four trials that did not fulfil our selection criteria were excluded. The remaining nine trials included 18,561 pregnant women and their 18,695 infants in both high- and low-risk pregnancies from seven clinical centers in the United States, Europe, and Australia. Overall, a statistically significant decrease was associated with routine EFM for neonatal seizures (relative risk (RR) 0.51, 95% confidence interval (CI) 0.32-0.82). The protective effect for neonatal seizures was only evident in studies with high-quality scores. No significant differences were observed in 1-minute Apgar scores below four or seven, rate of admissions to neonatal intensive care units, perinatal deaths or cerebral palsy. An increase associated with the use of EFM was observed in the rate of cesarean delivery (RR 1.41, 95% CI 1.23-1.61) and operative vaginal delivery (RR 1.20, 95% CI 1.11-1.30).

The only clinically significant benefit from the use of routine continuous EFM was in the reduction of neonatal seizures. In view of the increase in cesarean and operative vaginal delivery, the long-term benefit of this reduction must be evaluated in the decision reached jointly by the pregnant woman and her clinician to use continuous EFM or intermittent auscultation during labor.