The relative impact of labor induction versus improved labor management: Before and after the ARRIVE (a randomized trial of induction vs. expectant management) trial.

OBJECTIVE:To evaluate the association of labor induction on cesarean delivery and other maternal and neonatal outcomes in low-risk, full-term patients in community hospitals during a period of concerted effort to safely prevent cesarean delivery. METHODS:We performed a retrospective cohort study using the California Maternal Data Center comprised linked discharge diagnoses and birth certificate data for all low-risk, nulliparous, term, singleton, vertex (NTSV) individuals between 39 and 41 weeks from three Sacramento Valley community hospitals from 2016 to 2022 (N = 10,821) during a period of state-wide efforts to safely reduce cesarean rates. Logistic regression was used to calculate odds ratios (ORs) and adjusted odds ratios (aORs) after labor induction in two time periods before and after the ARRIVE trial. RESULTS:During the study period, labor induction increased from 14.7% to 23.1%. Controlling for maternal age, pre-pregnancy BMI, birthweight, maternal race and ethnicity, birthplace, English language, gestational age, Medicaid status, delivery year, and labor induction was associated with an increased aOR of 1.67 (95% CI 1.48-1.89) for cesarean delivery. We found a trend toward increased aOR of chorioamnionitis but no differences in blood transfusion, severe maternal morbidity, unexpected newborn complications, chorioamnionitis, operative vaginal delivery, maternal lacerations, and shoulder dystocia with labor induction. A decrease aOR of cesarean delivery was observed comparing all births in 2019-2021 to 2016-2018. CONCLUSION:Labor induction was associated with an increased aOR for cesarean delivery both before and after the ARRIVE trial. A decreased aOR for cesarean delivery was observed during the period of statewide efforts to safely reduce cesarean delivery both with and without labor induction.