A comparison between two differing ways of commencing labour and their effect on duration of labour in women giving birth for the first time.

Nulliparous women who have an obstetric indication for induction of labour, will be randomised to either a continuous oxytocin infusion and a liberal fluid strategy (comparator), or pulsatile oxytocin with a restricted fluid strategy (intervention). For pulsatile oxytocin, the stock solution is 6x more concentrated (30 IU oxytocin in 500 ml Hartmann's solution). The equivalent dose of oxytocin, relative to the continuous oxytocin infusion arm is given, which equates to 0.1 ml of the concentrated oxytocin stock solution given every 3 minutes. Similarly, to the continuous oxytocin infusion arm, the dose is increased every 30 minutes, until 4 uterine contractions occur within 10 minutes. The equivalent dose to 192 ml/hr continuous oxytocin is 1.6 ml every 3 minutes. A background infusion of Hartmann's solution is provided at 40 ml/hr and boluses of this IV fluid are contraindicated for the following conditions: 1. Inability to void every 2 hours 2 Presence of ketones in the urine 3. Pre-loading prior to the establishment of epidural analgesia 4. Treatment of hypotension, post establishment of epidural analgesia 5. Treatment of a non-reasuring CTG trace Women are allowed to eat and drink ad libitum