3.5.2 Intravenous infusion of oxytocin

This is frequently used to expedite labour after either spontaneous or artificial rupture of the membranes. The combination with early amniotomy is often called “active management of labour”, and as such it was first advocated in Ireland (O’Driscoll et al 1973, O’Driscoll and Meagher 1986). In more or less modified form the technique has been widely adopted across the world. According to the original protocols for the active management of labour, after early amniotomy hourly vaginal examinations are performed, and oxytocin is administered if the rate of cervical dilatation is less than 1 cm per hour. The practice has been investigated in a number of randomized trials (Read et al 1981, Hemminki et al 1985, Bidgood and Steer 1987, Cohen et al 1987, Lopez-Zeno et al 1992). Of the three trials providing data on the length of labour after oxytocin augmentation compared to control groups, only one showed a shorter mean duration with oxytocin. In one trial the women in the control group were encouraged to get out of bed and walk around, stand or sit as they wished. In this control group the mean duration of labour was slightly shorter than in the augmented group. Neither Apgar scores nor the incidence of admission to a special care nursery were different between oxytocin augmentation and control groups (Hemminki et al 1985). This study reported on the women’s views on the procedure. The majority said the augmentation procedure was unpleasant. More than 80% felt that augmentation had increased their pain. Half of the women in the control group who were ambulant said that this mobility had decreased their pain while 24% felt no difference.

In conclusion, it is not clear from the available data that liberal use of oxytocin augmentation (“active management of labour”) is of benefit to women and babies. Of course this does not mean that oxytocin is useless in the therapy of prolonged labour. However, there is no evidence that the prevention of prolonged labour by the liberal use of oxytocin in normal labour is beneficial. It is fair to ask whether labour augmented by oxytocin infusion can still be considered normal. In many places oxytocin infusions are only administered in hospital under the responsibility of the obstetrician. This is a reasonable precaution, given the unpredictable nature of artificially managed labour. As a general rule oxytocin should only ever be used to augment labour in facilities where there is immediate access to caesarean section should the need arise. The need for augmentation is considered an indication for referral to obstetric services with surgical facilities. Where available, subsequent fetal surveillance is not by intermittent auscultation but by electronic monitoring. The experience in Dublin during the randomized trial of intrapartum fetal heart rate monitoring also points in this direction: in the group monitored with auscultation the number of neonatal seizures was increased, but the majority of these infants were born from mothers who had augmentation with oxytocin during labour (MacDonald et al 1985). See also 2.7 Oxytocin augmentation is a major intervention and should only be implemented on a valid indication. The same holds true for the more modern variation of augmentation with prostaglandins, and for the induction of labour with these substances.