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.