Second stage cesarean section and the risk of preterm birth in subsequent pregnancies

Abstract

Objective To evaluate the risk of spontaneous preterm birth on subsequent pregnancies after second stage cesarean section. Methods This is a retrospective cohort study. Women were included if they had their two consecutive births in Toulouse University Hospital in the study period. The first birth was a singleton livebirth at term (≥37 weeks of gestation), divided in three categories according to the mode of delivery: vaginal delivery (group A), cesarean section before the second stage of labor (group B), cesarean section during the second stage of labor (group C). The subsequent pregnancy was the first subsequent pregnancy, conducted after 16 weeks of gestation. The primary outcome was spontaneous preterm birth in the subsequent pregnancy, defined as delivery before 37 weeks of gestation. Secondary endpoints included preterm rupture of membranes in the subsequent pregnancy. Results Between 2003 and 2018, 7776 women (84.7%) in group A, 1263 (13.8%) in group B and 143 (1.5%) in group C were included. The adjusted odds ratio of spontaneous preterm birth before 37 weeks of gestation after second stage cesarean section was 2.4 (group C vs group A + B, 95% confidence interval: 1.2–4.8), P = 0.01). The rate of preterm rupture of membranes was also significantly higher in group C (6% vs 2% in group A, P = 0.009, 6% vs 3% in group B, P= 0.05) with OR = 3.0 (group C vs group A + B, 95% CI: 1.55–6.16, P < 0.001). Conclusion History of term second stage of labor cesarean section is an independent risk factor for spontaneous preterm birth and for preterm rupture of membrane in the subsequent pregnancy.

Risk of Preterm Birth among Secundiparas with a Previous Cesarean due to a Failed Vacuum Delivery

“…Previous studies found an association between a second-stage cesarean sections (SS-CSs) and preterm birth (PTB) in the subsequent delivery [5][6][7][8][9][10][11]. This association may be the result of injury to the integrity of the cervix when attempting to extract a low, impacted fetal head during the SSCS.…”

Mode of birth in subsequent pregnancy when first birth was vacuum extraction or second stage cesarean section at a tertiary referral hospital in Uganda

“…However, the trend is comparable to outcomes of a systematic review and meta-analysis that focused on the relationship between mode of birth (CS vs. vaginal birth) in the first pregnancy and the risk of subsequent preterm birth. The meta-analysis showed that compared with vaginal birth in the first pregnancy, CS in the first pregnancy increases the risk of preterm birth in subsequent pregnancies [ 12 ], with second stage CS being an independent risk factor for subsequent preterm birth in another study [ 13 ]. It is hypothesized that the uterine structure and/or intrauterine microenvironment may be changed by previous CS, which increases the risk of subsequent preterm birth in the next pregnancies.…”

Cesarean Uterine Lacerations and Prematurity in the Following Delivery: A Retrospective Longitudinal Follow-Up Cohort Study

“…Previous studies searched for an association between SSCD and PTB based on the understanding that SSCD is associated with low-segment uterine incisional extension and that uterine extensions can cause mechanical injury to the cervix, possibly leading to cervical incompetence and PTB [3][4][5][6][7]11,16,[18][19][20]. Some found a positive association [4,5,18,19,21] and others did not find an association [7,16,20,22]. Most of these reports studied the association between SSCD and PTB [3][4][5]7,11,18,19] or SSCD and low-segment uterine incision extension [4,20] with only one of these studies combined all three [16].…”

“…Some found a positive association [4,5,18,19,21] and others did not find an association [7,16,20,22]. Most of these reports studied the association between SSCD and PTB [3][4][5]7,11,18,19] or SSCD and low-segment uterine incision extension [4,20] with only one of these studies combined all three [16]. Data are presented in Table 7.…”