Women delivered >120 minutes after presentation
Of the 83 women delivered >120 minutes after presentation, 4 experienced a sentinel event (1 cord prolapse and 3 uterine ruptures). Excluding the 4 women with a sentinel event, the majority of women (84%, n=66/79) had moderate variability, accelerations, or both on presentation (in the first 30 minutes of the tracing) including moderate variability, accelerations, or both. Of the 66 women with moderate variability and/or accelerations on presentation, 40% (27/66) retained these features (moderate variability, accelerations, or both) in the final 30 minutes before delivery (Figure 2, Table 4 ). The majority of the 27 women with moderate variability and/or accelerations, prior to delivery underwent cesarean delivery (n=16). Of the 39 women without moderate variability or accelerations prior to delivery the majority were by operative (10%, n=4) or non-operative vaginal delivery (54%, n=21). Mode of delivery did not differ significantly based on the whether the FHR tracing demonstrated moderate variability and/or accelerations prior to delivery (p=0.17).
The labor courses and clinical management of the 27 women with moderate variability, accelerations, or both on presentation and prior to delivery were heterogenous (Figure 3 ). Among this group there were 2 cases of intrauterine growth restriction and 2 cases of clinical chorioamnionitis. Seven women underwent a pre-labor cesarean delivery and 1 woman underwent a cesarean delivery in the first stage of labor. The remaining 8 women underwent cesarean delivery during second stages that ranged from 62 to 428 minutes; 3 of these cesareans occurred after failed operative vaginal delivery attempts. Of the 11 women undergoing vaginal delivery 6 had a second stage ≤1 hour, 3 had a second stage 1 to ≤3 hours, and 2 had a second stage >3 hours both of which required operative vaginal delivery. Overall, 8 of the 27 women had a second stage of ≥3 hours and 7 had labor courses ≥18 hours.