Fetal acoustic stimulation in the early intrapartum period as a predictor of subsequent fetal condition.

ABSTRACT

Fetal acoustic stimulation has recently received much attention in the literature. This study evaluates fetal acoustic stimulation in the early intrapartum period as a predictor of subsequent fetal condition. The study group consisted of 201 patients, approximately 60% of whom had complicated pregnancies. All were in the latent phase of labor with singleton, vertex-presenting fetuses. Gestational age ranged from 37 to 43 weeks. Fourteen of the 201 fetuses (7%) showed a nonreactive response to fetal acoustic stimulation and those fetuses were at significantly greater risk of initial and subsequent abnormal fetal heart rate patterns, meconium staining, and cesarean delivery because of fetal distress and Apgar scores less than 7 at both 1 and 5 minutes. Transient fetal heart rate decelerations after a reactive response occurred in 25% of patients; however, fetal outcome was not worse in this group. A reactive response to fetal acoustic stimulation was associated with high specificity and negative predictive values. Therefore we conclude that fetal acoustic stimulation in the early intraprtum period may discriminate the compromised from the noncompromised fetus.