A randomised controlled trial of intramuscular syntometrine and intravenous oxytocin in the management of the third stage of labour

Abstract

Objective To compare the efficacy and safety of intravenous oxytocin with intramuscular syntometrine in the management of the third stage of labour. Design A prospective randomised trial.Setting A university teaching hospital.Methods A total of 991 women having a singleton pregnancy and vaginal delivery were randomised by a computer-generated number to receive either 1ml syntometrine intramuscularly or 10 units of intravenous Syntocinon after delivery of the anterior shoulder of the fetus. Main outcome measures Blood loss during delivery, rate of postpartum haemorrhage, need for repeated oxytocics, haemoglobin level before and 24 hours after delivery, duration of third stage, need for manual removal of placenta and sides effects including hypertension, nausea, vomiting, headache and chest pain. Results The use of intravenous oxytocin was associated with a reduction in postpartum blood loss ( P < 0.001) but there was no difference in the risk of postpartum haemorrhage in the need for repeated oxytocic injections and the drop in peripartum haemoglobin level between the two groups. There was also no difference in the risk of prolonged third stage, or in the need for manual removal of placenta. The use of syntometrine was associated with a higher risk of hypertension (RR 2.39, 95% CI 1.00 -5.70). Other side effects were mild in nature with no differences between the two groups. Conclusions There are no important clinical differences in the effectiveness of intramuscular syntometrine and intravenous oxytocin for the prevention of postpartum blood loss. Intravenous oxytocin is less likely to cause hypertension.

A randomised trial of carbetocin versus syntometrine in the management of the third stage of labour

“…Despite the low incidence of postpartum haemorrhage in both treatment groups of our women, about 50 and 20% of the whole study group had more than 10 and 20% drop in haemoglobin level within 48 hours, respectively. These figures were consistent with our previous studies conducted in a similar population 7,16 and confirmed that the clinical estimation of blood loss in childbirth is inaccurate. 17,18 These suggested that the conventional definition of postpartum haemorrhage of blood loss > 500 ml is of little clinical use, and we agreed a peripartum fall in haemoglobin level more than 10% as the recommended diagnostic criteria for primary postpartum haemorrhage.…”

“…Nausea and vomiting was recorded in 7.3 and 6.7% of women in the syntometrine group and the incidence was significantly higher than the 1.3 and 0.7% in the carbetocin group. Nausea and vomiting caused by syntometrine was also observed in our previous studies with similar incidence 7 . Similar to oxytocin, carbetocin is less likely to cause hypertension than syntometrine.…”

“…This mixture combines the rapid onset of action of oxytocin and the sustained effect of ergometrine and is one of the most popular uterotonic agents used in the third stage of labour. IM syntometrine is shown to be as effective as intravenous oxytocin, 7 and it appears to be associated with a small but statistically significant reduction in the risk of postpartum haemorrhage when compared with oxytocin if blood loss is between 500 and 1000 ml 5 . Because ergotamine can stimulate smooth muscle contraction and vasoconstriction, it may raise blood pressure 8 and rarely lead to coronary artery spasm; 9 therefore, syntometrine is contraindicated in women with asthma, hypertension or cardiac disease.…”