Trial and error - Outcome of breech presentation depending on birth mode and root cause analysis of severe adverse...

The debate about the safest birth mode for breech presentation at term remains unresolved. The comparison of a vaginal breech birth (VBB) with an elective caesarean section (CS) regarding fetal outcomes favors the CS. However, the question of whether attempting a VBB is associated with poorer fetal outcomes is examined in this study. Additionally, the study evaluates factors contributing to a successful VBB and illustrates possible errors in VBB management.

We performed a retrospective analysis of term breech births over 15 years in a Perinatal Center Level I regarding fetal, maternal, and obstetric outcomes by comparing successful with unsuccessful VBB attempt and all attempted VBB vs. CS including a multivariate analysis of predictors for a successful VBB. A root cause analysis of severe adverse events (SAE) was conducted to evaluate factors leading to poorer fetal outcomes in VBB.

Of 863 breech cases, in 78 % a CS was performed and in 22 % a VBB was attempted, with 57 % succeeding. Comparing successful with unsuccessful VBB attempts, successful VBB showed significantly lower maternal blood loss (p < 0.001) but poorer umbilical arterial pH (UApH) (p < 0.001), while other fetal outcome parameters showed no significant differences. Predictive factors for a successful VBB attempt were a body mass index (BMI) below 30.0 kg/m² (p = 0.010) and multiparity (p = 0.003). Comparing all attempted VBB to CS, maternal blood loss was significantly higher in CS (p < 0.001), while fetal outcomes were significantly worse in VBB attempts, included poorer Apgar scores (p < 0.001), poorer UApH values (p < 0.001), higher transfer rate to the Neonatal Intensive Care Unit (NICU) (p < 0.001) and higher rate of respiratory support in the first 24 h (p = 0.003).

The failed attempt of VBB indicates significantly worse UApH without lower Apgar scores or higher transfer rate to the NICU. The likelihood of a successful VBB is 9% lower with obesity and 2.5 times higher in multiparous women. Attempting a VBB should include detailed pre-labor counseling, regarding predictive success factors, an experienced team, and consistent management during birth.