A prospective randomized study was performed to evaluate the influence of epidural analgesia compared to parenteral pethidine in parturients with pain in the first stage of labour on the progress of labour and the frequency of instrumental deliveries. There was no significant difference in the two groups in the duration of either the first or second stage of labour. The overall instrumental delivery rate was 25%, with no difference between the groups. The analgesic efficacy of the epidural blockade was significantly better than that of parenteral pethidine. We conclude that epidural bupivacaine with our technique and obstetric practice did neither prolong labour nor increase the frequency of instrumental delivery.