The impacted foetal head at caesarean section: incidence and techniques used in a single UK institution

An impaction of the foetal head at caesarean section is a topical concern in modern obstetric practice. The management options for this problem are well described but the incidence or even definition of impaction, is unknown. The primary aim of this study was to ascertain the incidence of impacted foetal head at CS in labour. This prospective study used data from all women undergoing CS during a 12-month period in a single unit. Following completion of all CS, the surgeon completed a questionnaire covering: cervical dilation at time of CS; if the surgeon felt there was a difficulty in delivering the foetal head as an indicator of impaction, as well as the other techniques utilised. Of 440 EMCS in labour, 18% (n = 81) reported a difficulty delivering the head, which was most common at cervical dilation ≥8 cm (n = 124, 48%). A difficulty with the delivery of the foetal head was associated with 36% increased measured blood loss. Impact statement What is already known on this subject? Impaction of the foetal head at a caesarean section is a recognised complication of CS in late labour but there are no reliable data on the incidence of the problem. It is poorly defined and yet many techniques and devices have been described to overcome this problem, however, optimal management remains uncertain. What do the results of this study add? The primary aim of this study was to determine the incidence of the impacted foetal head during CS in labour as determined by whether the surgeon experienced difficulty with delivery of the head. We report that at least some difficulty in delivering the foetal head at CS is common, and most often encountered when cervical dilation is ≥8 cm. When additional manoeuvres were required, the 'push' technique was exclusively adopted with implications for training. A difficulty in delivering the foetal head was associated with a 36% increase in the measured maternal blood loss. What are the implications of these findings for clinical practice and/or further research? Further multi-centre investigation is required to ascertain incidence of this obstetric problem with predicting factors determined. This work will inform decisions about the optimal management.