This was a retrospective study of acoustic stimulation response and perinatal outcome of 688 fetuses undergoing nonstress testing. Acoustic stimulation was performed within 7 days of delivery, and responses were classified based on the presence of an acceleration, deceleration, or both. Responses were correlated with perinatal outcome. Abnormal outcome was defined as: cesarean section for nonreassuring fetal heart rate patterns with an acidotic umbilical artery cord gas; delivery at less than 32 weeks for nonreassuring antenatal fetal testing; meconium aspiration syndrome or mechanical ventilation at 36 weeks or greater; neonatal seizures; 5-minute Apgar score less than 7; and stillbirth. Fetuses who demonstrated deceleration responses were significantly more likely to have abnormal perinatal outcomes when compared with those with acceleration responses (p < 0.001). Although combination acceleration-deceleration responses were more often associated with abnormal perinatal outcome when compared with pure acceleration responses, differences were not significant. A deceleration response following acoustic stimulation is associated with increased risk for adverse perinatal outcome and may merit further evaluation.