This randomised controlled trial aimed to compare the efficacy of intramuscular syntometrine with intravenous syntocinon, in preventing postpartum haemorrhage. A total of 686 women were randomised into two groups; one receiving intramuscular syntometrine and the other receiving intravenous syntocinon, as part of the active management of the third stage of labour. There was no difference in the mean blood loss between the two groups. However, there was an increased incidence of having a diastolic blood pressure of >90, 30 min after the delivery (p = 0.004), with intramuscular syntometrine. Therefore, it can be concluded that 1 ml of intramuscular syntometrine and 10 units of intravenous syntocinon are equally effective in preventing postpartum haemorrhage.