Vaginal breech delivery at term and neonatal morbidity and mortality - a population-based cohort study in Sweden.

Introduction: The routine to deliver almost all term breech cases by elective cesarean section (CS) has continued to be debated due to the risk of maternal and neonatal complications. The aims of the study were (1) to investigate if mode of delivery impacts on the risk of morbidity and mortality among term infants in breech presentation and (2) to compare the rates of severe neonatal complications and mortality in relation to presentation and mode of delivery.

Methods: This population-based cohort study used data from the Swedish Medical Birth Register. All women (and their newborn infants) with singleton pregnancies who gave birth at term to an infant in breech (n = 27,357) or cephalic presentation (n = 837,494) between 2001 and 2012 were included. Births with vacuum extraction and induced labors were excluded, as well as antepartum stillbirths, births with infants diagnosed with congenital malformations and multiple births.

Results: On one hand, the rates of neonatal complications and mortality were higher among infants born in vaginal breech compared to the vaginal cephalic group. On the other hand, after CS, the rates of all neonatal complications under study and neonatal mortality were lower among infants in breech presentation than in those in cephalic presentation. After adjustment for confounders, infants delivered in vaginal breech had 23.8 times higher odds AOR (ratio) for brachial plexus injury, 13.3 times higher odds ratio for Apgar score <7 at 5 min, 6.7 times higher odds of intracranial hemorrhage (ICH), or convulsions and 7.6 higher odds ratio for perinatal mortality than those delivered by elective CS.

Conclusions: Despite a probable selection of women who before-hand were considered at low risk and, therefore, could be recommended vaginal breech delivery, infants delivered in vaginal breech faced substantially increased risks of severe neonatal complications compared with infants in breech presentations delivered by elective CS. Key message Vaginal breech delivery is associated with increased risk for severe neonatal complications.