Main Findings
This national retrospective cohort study analyzed data from a total of 1,885,694 singleton, non-anomalous, low-risk pregnancies in the United States of America. From a maternal perspective, our data demonstrates a significantly lower frequency of triple I and cesarean delivery in women who underwent induction of labor at 39 weeks gestation as compared to the expectant management group. Induction of labor was associated with increased rates of cesarean hysterectomy. Although the risk was found to be 30% higher than the expectant management group, it is important to note that the absolute risk for this complication remains very low and was detected due to this study’s large sample size. Labor induction did not result in any statistically significant difference in the frequency of blood transfusion, ICU admission, or uterine rupture when the two groups were compared. From a neonatal perspective, our data demonstrates that labor induction at 39 weeks gestation resulted in a significantly lower frequency of 5 minute Apgar ≤ 3, requirement for ventilation, seizures and/or NICU admission than in the expectant management group. In contrast, labor induction did not result in any significant difference in the frequency of neonatal death between the two groups.
Taken together, these findings demonstrate that induction of labor at 39 weeks gestation is associated with: (i) a lower risk of developing triple I and requiring a cesarean delivery, (ii) a small increased risk for cesarean hysterectomy, and (iii) a significantly reduced frequency of neonatal morbidity when compared with an expectantly managed pregnancy.