Cesarean Delivery in the Second Stage of Labor and the Risk of Subsequent Premature Birth

Abstract

(Am J Obstet Gynecol. 2017;217(1):63.e1–63.e10) Cesarean delivery rates are on the rise in the United States, in part because of the increased use of cesarean delivery rather than forceps and vacuum deliveries for fetal distress and arrest disorders in the second stage of labor. However, cesarean delivery in the second stage of labor can be risky due to the difficulty of delivering a deeply impacted fetal head. Cohort studies have shown increased risk of extensions of the uterine incision, bladder injury, and postpartum hemorrhage in such deliveries. Surgical trauma to the cervix from other procedures has been demonstrated to significantly increase the risk of subsequent premature delivery. For these reasons, the authors hypothesized that second-stage cesarean deliveries may increase the rate of subsequent spontaneous preterm delivery.

Does previous caesarean section at full dilatation increase the likelihood of subsequent spontaneous preterm birth?

“…Also in agreement with Wood et al 20 we found no increased risk of SPTB in pregnancies subsequent to instrumental deliveries.…”

“…The same comparison in our study showed a significantly increased rate of SPTB, but the OR of 2.2 (95% CI 1.3-3.8, P = 0.003) was lower. Our results were more comparable with those found by Wood et al 20 They showed a relative risk of 1.57 (95% CI 1.43-1.73) of having a SPTB <37 weeks among women who had a fully dilated CS.…”

“…11,18,19 Our study has shown a statistically significant two-fold increase in the rate of Our finding that 20% of intrapartum CS were performed in the second stage of labour is consistent with the literature. 3,9,11,20 Women in our study who had a CS at full dilatation did have a significantly longer second stage compared to the instrumental and unassisted vaginal delivery group. However, previous studies 11,20 have not shown a significant association between duration of second stage alone and SPTB in multivariate analysis.…”

“…3,9,11,20 Women in our study who had a CS at full dilatation did have a significantly longer second stage compared to the instrumental and unassisted vaginal delivery group. However, previous studies 11,20 have not shown a significant association between duration of second stage alone and SPTB in multivariate analysis.…”

“…There is growing acknowledgement of the consequences of fully dilated CS. 11,20,22 Levine et al (2015) 11 found that after a full-term second-stage CS women had a significantly higher than expected rate of subsequent SPTB (13.5%) compared to a firststage CS (2.3%) with an OR of 5.8 (95%CI 1.08-30.8, P = 0.04). The same comparison in our study showed a significantly increased rate of SPTB, but the OR of 2.2 (95% CI 1.3-3.8, P = 0.003) was lower.…”