Intravenous prostaglandin for induction of labour.

BACKGROUND

Intravenous prostaglandin E2 and F2 alpha can be used to induce labour. The use of intravenous prostaglandins in this context has been limited by perceived unacceptable maternal side effect profiles. This is one of a series of reviews of methods of cervical ripening and labour induction using standardised methodology.

OBJECTIVES

To determine the effects of intravenous prostaglandin for third trimester cervical ripening or induction of labour.

SEARCH STRATEGY

The Cochrane Pregnancy and Childbirth Group trials register, The Cochrane Controlled Trials Register and bibliographies of relevant papers.

SELECTION CRITERIA

The criteria for inclusion included the following: (1) clinical trials comparing intravenous prostaglandin used for third trimester cervical ripening or labour induction with placebo/no treatment or other methods listed above it on a predefined list of labour induction methods; (2) random allocation to the treatment or control group; (3) adequate allocation concealment; (4) violations of allocated management not sufficient to materially affect conclusions; (5) clinically meaningful outcome measures reported; (6) data available for analysis according to the random allocation; (7) missing data insufficient to materially affect the conclusions.

DATA COLLECTION AND ANALYSIS

A strategy has been developed to deal with the large volume and complexity of trial data relating to labour induction. This involves a two-stage method of data extraction. The initial data extraction is done centrally, and incorporated into a series of primary reviews arranged by methods of induction of labour, following a standardised methodology. The data will then be extracted from the primary reviews into a series of secondary reviews, arranged by category of woman. To avoid duplication of data in the primary reviews, the labour induction methods have been listed in a specific order, from one to 25. Each primary review includes comparisons between one of the methods (from two to 25) with only those methods above it on the list.

MAIN RESULTS

Thirteen trials were eligible for inclusion in this review. Two trials (comprising 400 women) compared intravenous prostaglandin E2 to intravenous oxytocin, a further seven trials (comprising 590 women) compared intravenous prostaglandin F2 alpha to intravenous oxytocin. Two trials (comprising 115 women) each randomised women to one of three treatment arms namely intravenous oxytocin or intravenous prostaglandin F2 alpha or prostaglandin E2. One trial reported a comparison of combined oxytocin and prostaglandin F2 alpha and oxytocin alone in 20 women and lastly one trial compared extra amniotic prostaglandin E2 versus intravenous prostaglandin E2 (40 women). The use of intravenous prostaglandin was associated with higher rates of uterine hyperstimulation with changes in the fetal heart rate (relative risk (RR) 6.76, 95% confidence interval (CI) 1.23-37.11) and without (RR 4.25, 95%CI 1.48-12.24) compared to oxytocin. Use of prostaglandins was also associated with significantly more maternal side effects (gastrointestinal, thrombophlebitis and pyrexia, RR 3.75, 95% CI 2.46-5.70) than oxytocin. Prostaglandin was no more likely to result in vaginal delivery than oxytocin (RR 0.85, 95% CI 0.61-1.18). No significant differences emerged from subgroup analysis or from the trials comparing combination oxytocin/prostaglandin F2 alpha and oxytocin or extra amniotic versus intravenous prostaglandin E2.

REVIEWER'S CONCLUSIONS: Intravenous prostaglandin is no more efficient than intravenous oxytocin for the induction of labour but its use is associated with higher rates of maternal side effects and uterine hyperstimulation than oxytocin. No conclusions can be drawn form the comparisons of combination of prostaglandin F2 alpha and oxytocin compared to oxytocin alone or extra amniotic and intravenous prostaglandin E2.