Background: Many medical practitioners have adopted the practice of caesarean section for preterm infants in breech presentation based on term infant data. Some studies have highlighted deleterious effects on survival, such as intraventricular haemorrhage and periventricular leucomalacia, while others have reported no difference from the outcomes after vaginal delivery.
Objective: To compare outcomes of preterm infants of ≤32 weeks' gestational age who were in breech position at the time of birth according to mode of birth in Canadian neonatal intensive care units (NICUs).
Settings: 29 Canadian NICUs.
Design: Neonates admitted to participating NICUs in the Canadian Neonatal Network between 2003 and 2007 were included in this retrospective study. Infants who were in breech position at the time of birth were divided into two groups: vaginal birth (VB) and caesarean section (CS). Data on common neonatal outcomes were compared using univariate and multivariate logistic regression.
Main outcome measures: Neonatal mortality and other neonatal morbidities.
Results: Of 3552 preterm infants in breech position at birth, 2937 (83%) were delivered by CS and 615 (17%) by VB. Multivariate regression analysis with adjustment for perinatal risk factors indicated that VB was associated with an increased risk of death (OR 1.7; 95% CI 1.3 to 2.3), chronic lung disease (OR 1.5; 95% CI 1.1 to 1.9) and severe retinopathy of prematurity (OR 1.6; 95% CI 1.1 to 2.3).
Conclusion: Vaginal birth for preterm infants in breech presentation is possibly associated with a higher risk of adverse neonatal outcomes compared with caesarean birth in Canadian NICUs. It is not clear whether adverse outcomes are due to the mode of delivery or whether breech birth is associated with other risk factors, an issue that can only be resolved by a randomised controlled trial.