The effect of lumbar epidural analgesia on the rate of cervical dilatation and the outcome of labour of spontaneous onset.

A study of 1055 spontaneous labours is presented relating progress and outcome to the presence of a lumbar epidural block in 282 of these patients and to the need for oxytocin augmentation in 427. Graphs for cervical dilatation starting at admission to hospital were constructed for normal and dysfunctional labours of spontaneous onset. Patients requiring augmentation of labour had a lesser cervical dilatation on admission to hospital, a longer first stage, more instrumental deliveries, more Caesarean sections and a greater number of babies with a low Apgar score. An epidural block had no effect on either the duration of first stage or the rate of cervical dilatation but was associated with a 20-fold increase in rotational forceps delivery and no increase in Caesarean section rate. With an epidural block there was no increase in the number of babies with cerebral irritation or low Apgar scores and there was a statistically significant improvement in the Apgar scores of babies of mothers in augmented dysfunctional labour who had an epidural block. The incidence of rotational forceps delivery in patients with an epidural block could be reduced with safety by allowing such patients to have a longer second stage before considering interference purely for delay.