Factors affecting mode of delivery in labour following a single previous birth by caesarean section

Summary

We evaluated the course of labour and the mode of delivery in women delivered between 1 June 1992 and 31 May 1994 whose only previous delivery was by a transverse lower segment caesarean section in the National Maternity Hospital. The purpose of the study was to determine if routine measured clinical factors were associated with mode of delivery. During a 2 year period the details of labour and delivery were collected prospectively on a cohort of 239 patients and entered on to a computer data base. In a total of 12 387 deliveries 239 patients presented for delivery when their only other pregnancy had resulted in delivery by transverse lower segment caesarean section in the hospital (2 per cent). Of these cases 44 were delivered by repeat caesarean section before labour (18 per cent), 195 were allowed a trial of labour and of these cases 150 had a vaginal delivery (77 per cent). There was no case of uterine dehiscence. There was a 95 per cent chance of a vaginal delivery when the head was engaged on admission in labour. Trial of labour should be offered to most women whose first pregnancy ended in a transverse lower segment caesarean section. Findings in labour in the second pregnancy may be more relevant to a successful trial of labour than information from the first labour and delivery.