Risk factors and outcomes in "well-selected" vaginal breech deliveries: a retrospective observational study.

Objective: To assess risk factors for adverse perinatal and neonatal outcomes in "well-selected" singleton vaginal breech deliveries at term.

Methods: During the time span from January 2008 up to April 2015 a total of 786 singleton term breech deliveries with a planned vaginal delivery were identified in a retrospective observational study at Helsinki University Central Hospital, Finland. The study's end point was a composite of adverse perinatal and neonatal outcomes. Infants with an adverse outcome were compared to all spontaneous singleton vaginal breech deliveries with normal perinatal and neonatal outcomes. A multivariate logistic regression model was used to analyze associations between adverse neonatal outcomes and several variables. The secondary outcome was the severe morbidity rate according to the criteria of the term breech trial.

Results: An adverse neonatal outcome was recorded for 38 (4.8%) infants. According to the study the second delivery stage lasting <40 min [adjusted odds ratio (aOR): 0.34, 95% confidence interval (95% CI): 0.15-0.79] was associated with lower odds and had a protective effect against adverse outcomes. Epidural anesthesia (aOR: 2.88, 95% CI: 1.08-7.70) was associated with higher adverse outcomes. The incidence rate of severe morbidity was 1.3% (10/787).

Conclusion: Adverse neonatal outcomes in well-selected breech deliveries are associated with a prolonged second delivery stage lasting >40 min and with epidural anesthesia.