Maternal and neonatal outcome of reverse breech extraction of an impacted fetal head during caesarean section in advanced stage of labour: a retrospective cohort study

BACKGROUND: Caesarean section with extraction of a deeply impacted fetal head is technically challenging and is associated with serious maternal and neonatal complications. The purpose of the study was to identify risks and evaluate selected outcome parameters associated with difficult fetal head extraction during caesarean section in advanced labour comparing two different extraction techniques (head pushing vs. reverse breech). METHODS: This retrospective cohort study was conducted at the Division of Obstetrics in a tertiary care hospital in Zurich, Switzerland. 629 women at term with a singleton pregnancy in cephalic presentation during advanced intrapartum caesarean section from December 2012 until December 2016 were evaluated. Primary outcome was the incidence of uterine incision extensions. Secondary outcomes were other selected maternal and neonatal outcome parameters. Data analysis was performed using SPSS with Mann-Whitney U independent sampling test and two-tailed Fisher’s exact test (p < 0.01). RESULTS: Difficult fetal head extractions are associated with significantly elevated maternal and neonatal risks. When performed by reverse breech technique, significant lower rates of extensions of the uterine incision, shorter operation times and less operative blood loss were identified compared to the head pushing method. No statistically significant differences for the neonatal outcomes were described so far. However, among the group of difficult fetal delivery with the head pushing method two neonates had perinatal skull fractures, with one of those resulting in neonatal death. CONCLUSIONS: The head pushing method is associated with higher maternal morbidity than the reverse breech method for extraction of a deeply engaged fetus during intrapartum caesarean section in advanced stage of labour.