Trial of labour after caesarean section and the risk of neonatal and infant death: a nationwide cohort study

Risk of stillbirth after a previous caesarean delivery: A Swedish nationwide cohort study

OBJECTIVES

To investigate the risk of stillbirth in relation to (1) a previous caesarean delivery (CD) compared with those following a vaginal birth (VB); and (2) vaginal birth after caesarean (VBAC) compared with a repeat CD.

DESIGN

Population-based cohort study.

SETTING

The Swedish Medical Birth registry.

POPULATION

Women with their first and second singletons between 1982 and 2012.

METHODS

Multivariable logistic regression models were performed to estimate adjusted odds ratios (aOR) and 95% confidence intervals (CI) of the association between CD in the first pregnancy and stillbirth in the second pregnancy and the association between VBAC and stillbirth. Sub-group analyses were performed by types of CD and timing of stillbirth (antepartum and intrapartum).

MAIN OUTCOME MEASURES

Stillbirth (antepartum and intrapartum fetal death).

RESULTS

Of the 1 771 700 singleton births from 885 850 women, 117 114 (13.2%) women had a CD in the first pregnancy, and 51 755 had VBAC in the second pregnancy. We found a 37% increased odds of stillbirth (aOR 1.37; 95% CI 1.23-1.52) in women with a previous CD compared with VB. The odds of intrapartum stillbirth were higher in the previous pre-labour CD group (aOR 2.72; 95% CI 1.51-4.91) and in the previous in-labour CD group (aOR 1.35; 95% CI 0.76-2.40), although not statistically significant in the latter case. No increased odds were found for intrapartum stillbirth in women who had VBAC (aOR 0.99; 95% CI 0.48-2.06) compared with women who had a repeat CD.

CONCLUSIONS

This study confirms that a CD is associated with an increased risk of subsequent stillbirth, with a greater risk among pre-labour CD. This association is not solely mediated by increases in intrapartum asphyxia, uterine rupture or attempted VBAC. Further research is needed to understand this association, but these findings might help healthcare providers to reach optimal decisions regarding mode of birth, particularly when CD is unnecessary.

Planned mode of birth after previous cesarean section: A structured review of the evidence on the associated outcomes for women and their children in high-income setting

In many high-income settings policy consensus supports giving pregnant women who have had a previous cesarean section a choice between planning an elective repeat cesarean section (ERCS) or planning a vaginal birth after previous cesarean (VBAC), provided they have no contraindications to VBAC. To help women make an informed decision regarding this choice, clinical guidelines advise women should be counseled on the associated risks and benefits. The most recent and comprehensive review of the associated risks and benefits of planned VBAC compared to ERCS in high-income settings was published in 2010 by the US Agency for Healthcare Research and Quality (AHRQ). This paper describes a structured review of the evidence in high-income settings that has been published since the AHRQ review and the literature in high-income settings that has been published since 1980 on outcomes not included in the AHRQ review. Three databases (MEDLINE, EMBASE, and PsycINFO) were searched for relevant studies meeting pre-specified eligible criteria, supplemented by searching of reference lists. Forty-seven studies were identified as meeting the eligibility criteria and included in the structured review. The review suggests that while planned VBAC compared to ERCS is associated with an increased risk of various serious birth-related complications for both the mother and her baby, the absolute risk of these complications is small for either birth approach. The review also found some evidence that planned VBAC compared to ERCS is associated with benefits such as a shorter length of hospital stay and a higher likelihood of breastfeeding. The limited evidence available also suggests that planned mode of birth after previous cesarean section is not associated with the child’s subsequent risk of experiencing adverse neurodevelopmental or health problems in childhood. This information can be used to manage and counsel women with previous cesarean section about their subsequent birth choices. Collectively, the evidence supports existing consensus that there are risks and benefits associated with both planned VBAC and ERCS, and therefore women without contraindications to VBAC should be given an informed choice about planned mode of birth after previous cesarean section. However, further studies into the longer-term effects of planned mode of birth after previous cesarean section are needed along with more research to address the other key limitations and gaps that have been highlighted with the existing evidence.

Maternal and neonatal outcomes in the following delivery after previous preterm caesarean breech birth: a national cohort study

The objective of this retrospective, nationwide Finnish population-based cohort study was to determine whether there is an association between preterm caesarean breech delivery in the first pregnancy and maternal and neonatal morbidity in the subsequent pregnancy and delivery. We identified all singleton preterm breech birth in Finland from 2000 to 2017 (n = 1259) and constructed a data set of the first two deliveries for these women. We compared outcomes of the following pregnancy and delivery among women with a previous preterm caesarean breech section with the outcomes of women with one previous vaginal preterm breech birth. p Value, odds ratio, and adjusted odds ratio were calculated. Neonates of women with a previous caesarean preterm breech delivery had an increased risk for arterial umbilical cord pH below seven (1.2% versus 0%; p value .024) and a higher rate of neonatal intensive care unit admission [22.9% versus 15% adjusted OR 1.57 (1.13-2.18); p value <.001]. The women with a previous caesarean section had a higher rate of uterine rupture (2.3% versus 0%; p value .001). They were also more likely in the subsequent pregnancy to have a planned caesarean section [19.9% versus 4% adjusted OR 8.55 (4.58-15.95), an emergency caesarean section [21.5% versus 9.7% adjusted OR 2.16 (1.28-2.18)], or an instrumental vaginal delivery [9.3% versus 3.8% adjusted OR 2.38 (1.08-5.23)].IMPACT STATEMENTWhat is already known on this subject? Vaginal birth after caesarean section is generally known to be associated with a higher risk of maternal and neonatal morbidity.What do the results of this study add? The following birth after previous caesarean preterm breech section is associated with a higher rate of uterine rupture and with a higher rate neonatal admission to the neonatal intensive care unit and more often an arterial umbilical cord pH below seven regardless of the mode of the following delivery, compared to women with a subsequent delivery after a previous vaginal preterm breech birth.What are the implications of these findings for clinical practice and/or further research? Our results must be considered when counselling patients regarding their first preterm breech delivery, as the selected method of delivery also affects the outcomes of subsequent pregnancies and deliveries.