Electronic fetal monitoring during labor.

The use of continuous electronic fetal monitoring (EFM) during the labors of both low- and high-risk obstetric patients has increased dramatically in the past decade. EFM is a screening tool used for the early detection of fetal hypoxia and prevention of its consequences. Fetal heart rate patterns generated should be thought of as either reassuring or not reassuring of fetal oxygenation. Combinations of nonreassuring patterns are very frequently associated with significant fetal hypoxia. Initially EFM was accepted without serious question of its benefits and risks. Recently more skeptical attitudes about EFM have developed, and studies evaluating the efficacy of EFM have increased. The use of EFM improves fetal outcome in high-risk pregnancies. There is no clear indication that EFM has an advantage over careful auscultation in low-risk pregnancies. The risks of continuous ultrasound and fetal and maternal infection following EFM appear minimal. The cesarean section rate has risen in recent years, but the contribution of EFM to this increase is not known. The psychologic and emotional risks of EFM have not been well defined.