(220) Standardizing induction of labor improves clinical outcomes

Objective: To assess the impact of a standardizing induction of labor (IOL) practices on length of IOL and maternal morbidity.

Study Design: This is a single center quality improvement project examining impact of standard IOL recommendations. The pre-implementation (pre) period was 8/1/2021-1/31/2022. The post-implementation (post) period was 3/1/2022-5/1/2022. Patients admitted for IOL with singleton gestation, intact membranes, and vertex presentation were included. We excluded patients with prior cesarean and fetal demise. The standardized recommendations included 1) combined ripening with foley balloon and misoprostol; 2) vaginal misoprostol preferred over buccal; 3) early amniotomy (≤ 4 cm); and 4) labor progress assessments every 4 hours. The primary outcome was duration of IOL. Length of time from oxytocin to rupture of membranes (ROM) was a process measure reflecting timing of amniotomy. Secondary outcomes included cesarean birth, chorioamnionitis, endometritis, and postpartum hemorrhage (PPH) defined as quantitative blood loss of > 1000 mL. Multiple linear regression adjusted the primary outcome for nulliparity and epidural use.

Results: There were 513 patients included (pre n=324, post n=189). There were no significant differences in age, race/ethnicity, initial cervical dilation, initial induction agent, parity, or gestational age at admission between pre and post (Table 1). Elective IOL accounted for almost half of IOL in both groups. Length of IOL was shorter in the post group overall (p=0.006, Table 2), among nulliparas (p=0.02), and among multiparas (p=0.001). After adjustment, post intervention demonstrated significantly shorter length of IOL by 2.4 (95% CI 1.4-3.5) hours. Time from oxytocin initiation to ROM (5.4 [95% CI 3.2-8.6] vs. 6.7 hours [95% CI 4.1-10.8], p=0.003) and chorioamnionitis (0.5 vs. 5.3%, p=0.005) were decreased post-intervention. There were no differences in cesarean, endometritis or PPH between groups.

Conclusion: Given increasing frequency of IOL, standardizing IOL management can improve delivery outcomes and is a useful target to optimize labor and delivery efficiency.