Risk factors for classical hysterotomy in twin pregnancies

Safety of performing classical versus low transverse caesarean sections in extremely preterm and very preterm births: Maternal and neonatal complications

AIMS

Improved survivability of extremely preterm infants has led to increased rates of caesarean sections. Short-term maternal and neonatal risks of classical caesarean sections (CCS) in the context of extreme prematurity remain unclear. The aim was to examine maternal and neonatal complications associated with CCSs versus low transverse caesarean sections (LTCS) at extremely preterm (23 0/7-27 6/7 weeks) and very preterm gestational ages (28 0/7-31 6/7 weeks).

METHODS

A retrospective cohort study was conducted at Royal Brisbane and Womens Hospital, Queensland, Australia between 2016 and 2020. Maternal and neonatal outcomes were examined using univariate and multivariate statistical analysis.

RESULTS

CCSs (extremely preterm: n = 93; very preterm: n = 83) were associated with higher estimated blood loss than LTCS (extremely preterm: n = 70; very preterm: n = 287) in very preterm births (CCS: 638 ± 410 mL; LTCS: 556 ± 397 mL; P = 0.01). There was no significant difference in composite maternal outcomes between CCS and LTCS for extremely preterm (adjusted odds ratio (aOR): 1.11; 95% confidence interval (CI): 0.58-2.12; P = 0.75) or very preterm births (aOR: 1.08; 95% CI: 0.63-1.94; P = 0.79) after accounting for multiple pregnancy, placenta accreta and non-cephalic fetal presentations. Although CCSs were associated with lower Apgar scores at 1 min post-birth than LTCSs at very preterm gestational ages (CCS: 5.58 ± 2.10; LTCS: 6.25 ± 2.14; P = 0.02), there was no statistical difference in the rates of intraoperative neonatal injuries or composite outcomes when corrected for low birth weight.

CONCLUSION

Short-term maternal and neonatal outcomes do not significantly differ between CCS and LTCS for extremely preterm or very preterm births.

Prior vertical uterine incision: Effect on subsequent pregnancy characteristics and outcomes

OBJECTIVE

To examine characteristics and outcomes of cesarean delivery (CD) in women with a history of vertical hysterotomy.

METHOD

This is a comparative study that retrospectively queried the National Inpatient Sample from October 2016 to December 2018. Pregnancy characteristics and surgical outcomes of CD among 18 575 women with prior vertical uterine incision were compared to 1 072 949 women with prior low-transverse incision, assessed by multivariable generalized estimating equation model and propensity score weighting.

RESULTS

In a multivariable analysis, women who had prior vertical uterine incision were more likely to have placenta percreta (odds ratio [OR] 3.41, 95% confidence interval [CI] 1.87-6.20), pre-labor uterine rupture (OR 2.70, 95% CI 1.52-4.80), in-labor uterine rupture (OR 2.33, 95% CI 1.55-3.51), and extreme preterm delivery <28 weeks (OR 17.8, 95% CI 15.2-20.7) in the current pregnancy, compared to those who had prior low-transverse uterine incision. In a weighted model, prior vertical hysterotomy was associated with increased surgical morbidity in current CD compared to prior low-transverse hysterotomy (10.6% vs. 4.8%, OR 2.02, 95% CI 1.81-2.26), including hemorrhage (OR 1.99, 95% CI 1.74-2.27) and hysterectomy (OR 3.67, 95% CI 2.97-4.53).

CONCLUSION

Prior vertical uterine incision at CD was associated with increased risk of placenta percreta, uterine rupture, particularly before labor, and adverse outcomes in the subsequent pregnancy.