Reduction in the cesarean section rate in nulliparous patients after administration of intravenous propranolol

A preliminary investigation to test the efficacy of intravenous propranolol in reducing the cesarean section rate in nulliparas in active labor and evaluate its effect on neonatal and maternal outcomes.

Fifty seven nulliparous patients admitted in active labor were randomly divided into two groups: a control group consisting of 23 patients, and a treatment group consisting of 34 patients given 2 mg of propranolol intravenously every 4 hours until delivery. Total length of labor, time from first administration of medication to delivery, incidence of cesarean section, APGAR scores, maternal and fetal morbidity were assessed.

A total of 4 cesarean sections were performed in each group (11.7% in the treatment group and 17.3% in the control group). The rate of cesarean section due to dystocia was 6.25 and 13.6% respectively (P = .367). Statistical significance was not reached due to the small number of subjects (students t test analysis). There was no increase in the incidence of low APGAR scores, intensive care unit admissions, abnormal heart rate patterns during labor, cesarean sections for fetal distress or maternal morbidity in the treated group.

Intravenous administration of 2 mg of propranolol every four hours is safe and not associated to increased neonatal or maternal morbidity. A 50% decrease in the incidence of cesarean sections can be documented among nulliparous patients treated with propranolol although the small numbers and overall low incidence of cesarean section in our population (14%) did not permit these differences to reach statistical significance.