Breech delivery at term in Denmark, 1982-92: a population-based case-control study.

The aim of the study was to determine the influence of intended mode of delivery on neonatal outcome in term breech delivery and to identify risk factors at intended vaginal delivery. Based on register data on all deliveries of non-malformed, singleton fetuses in breech presentation at term (n = 19,476) in Denmark, 1982-92, a review of medical records of all (n = 218) cases with Apgar score < 7 at 5 minutes, including intrapartum and early neonatal deaths and 412 controls, was performed. Planned vaginal delivery was associated with a 15 times greater risk of low Apgar score than elective Caesarean section. Low Apgar score was correlated with duration of second stage of labour, but not with age, parity, birthweight, induction, augmentation or duration of first stage of labour. In conclusion, a pre-labour decision on vaginal delivery was associated with a 15-fold increase in low Apgar score. Prediction of low Apgar score in women selected for vaginal delivery does not seem possible before the second stage of labour.