Does programmed intermittent epidural bolus improve childbirth conditions of nulliparous women compared with patient-controlled epidural analgesia?: A multicentre, randomised, controlled, triple-blind study.

Background: Epidural analgesia may change the mechanics of childbirth. These changes are related to the concentration of the local anaesthetic used epidurally but probably also to its mode of delivery into the epidural space.

Objective: To determine whether the administration of programmed intermittent epidural boluses (PIEB) improves the mechanics of second-stage labour compared with patient-controlled epidural analgesia (PCEA) with a background infusion.