The effect/use of the drug oxytocin as a treatment for slow progress in labour

Slow progress in the first stage of spontaneous labour may be caused by weak contractions of the womb. Doctors and midwives commonly give a drug called oxytocin with the aim of strengthening contractions and speeding up labour to avoid harm to both the mother and the newborn infant. The belief is that managing the labour in this way will enable progression to a normal vaginal delivery and reduce the need for caesarean section. However, others have been fearful that it has no effect on the type of delivery a woman might have and in other ways may do more harm than good. This review of eight studies, involving 1338 low-risk women in the first stage of spontaneous labour at term, showed that oxytocin did not reduce the need for caesarean sections. Neither did it reduce the need for forceps deliveries or increase the number of normal deliveries when compared with no treatment or delayed oxytocin treatment. Oxytocin seemed to shorten labour by nearly two hours on average. The uptake of epidurals was no different. It does not seem to cause harm to the mother or baby, but the sample size was too small to determine if its use has an effect on the death rates of babies. The decision whether to undergo this treatment is one that can reasonably be left to women to decide in the context of a reduction in the length of labour. The included trials used different doses of oxytocin, and different criteria for starting treatment in the delayed oxytocin arm.

Authors' conclusions: 

For women making slow progress in spontaneous labour, treatment with oxytocin as compared with no treatment or delayed oxytocin treatment did not result in any discernable difference in the number of caesarean sections performed. In addition there were no detectable adverse effects for mother or baby. The use of oxytocin was associated with a reduction in the time to delivery of approximately two hours which might be important to some women. However, if the primary goal of this treatment is to reduce caesarean section rates, then doctors and midwives may have to look for alternative options.

Read the full abstract...
Background: 

Slow progress in the first stage of spontaneous labour is associated with an increased caesarean section rate and fetal and maternal morbidity. Oxytocin has long been advocated as a treatment for slow progress in labour but it is unclear to what extent it improves the outcomes for that labour and whether it actually reduces the caesarean section rate or maternal and fetal morbidity. This review will address the use of oxytocin and whether it improves the outcomes for women who are progressing slowly in labour compared to situations where it is not used or where its administration is delayed.

Objectives: 

To determine if the use of oxytocin for the treatment of slow progress in the first stage of spontaneous labour is associated with a reduction in the incidence of caesarean sections, or maternal and fetal morbidity compared to situations where it is not used or where its administration is delayed.

Search strategy: 

We searched the Cochrane Pregnancy and Childbirth Group's Trials Register (23 February 2013) and bibliographies of relevant papers.

Selection criteria: 

Randomised controlled trials which compared oxytocin with either placebo, no treatment or delayed oxytocin in the active stage of spontaneous labour in low-risk women at term.

Data collection and analysis: 

Two authors independently assessed studies for inclusion, assessed risk of bias and extracted data. We sought additional information from trial authors.

Main results: 

We included eight studies in the review involving a total of 1338 low-risk women in the first stage of spontaneous labour at term. Two comparisons were made; 1) the use of oxytocin versus placebo or no treatment (three trials); 2) the early use of oxytocin versus its delayed use (five trials). There were no significant differences in the rates of caesarean section or instrumental vaginal delivery in either comparison. Early use of oxytocin resulted in an increase in uterine hyperstimulation associated with fetal heart changes. However, the early use of oxytocin versus its delayed use resulted in no significant differences in a range of neonatal and maternal outcomes. Use of early oxytocin resulted in a statistically significant reduction in the mean duration in labour of approximately two hours but did not increase the normal delivery rate. There was significant heterogeneity for this analysis and we carried out a random-effects meta-analysis; however, all of the trials are strongly in the same direction so it is reasonable to conclude that this is the true effect. We also performed a random-effects meta-analysis for the four other analyses which showed substantial heterogeneity in the review.