Bupivacaine paracervical block. Effects on the fetus and neonate.

To evaluate effects on the fetus and neonate, 53 paracervical blocks were administered to 38 low-risk parturients using a controlled superficial injection of 0.25% bupivacaine. Continuous fetal heart rate monitoring revealed no instance of bradycardia or late deceleration pattern. Apgar scores, cord arterial and venous pH values, and neurobehavioral evaluations of the neonates were similar to those observed in other low-risk patients. The effectiveness of pain relief of the blocks was less than expected or reported by other authors. Although we observed no harmful effects on the fetus or neonate from the superficial paracervical injection of bupivacaine, we did not find this combination of drug and technique to give dependable, effective pain relief in labor.