Intravenous versus intramuscular oxytocin injection for preventing uterine atonic primary postpartum haemorrhage in third stage of labour: A double-blind randomised controlled trial.

OBJECTIVES: To compare the efficacy and safety of intravenous and intramuscular oxytocin in preventing atonic primary postpartum haemorrhage in the third stage of labour.

METHODS: A double-blind randomised clinical study on consenting women without risk factors for primary postpartum haemorrhage in labour at term. Two hundred and thirty-two women were randomly allotted into intravenous ( n  = 115) and intramuscular ( n  = 117) oxytocin groups in the active management of the third stage of labour. All participants received 10 IU of oxytocin, either IV or IM, and 1 ml of water for injection as a placebo via a route alternate to that of administration of oxytocin within 1 min of the baby's delivery. The primary outcome measures were mean postpartum blood loss and haematocrit change. Trial Registration No.: PACTR201902721929705.

RESULTS: The baseline socio-demographic and clinical characteristics were similar between the two groups ( p  > 0.05). There was no statistically significant difference between the two groups with regards to the mean postpartum blood loss (254.17 ± 34.85 ml versus 249.4 ± 39.88 ml; p  = 0.210), haematocrit change (2.4 (0.8%) versus 2.1 (0.6%); p  = 0.412) or adverse effects ( p  > 0.05). However, the use of additional uterotonics was significantly higher in the intravenous group (25 (21.73%) versus 17 (14.53%); p  = 0.032).

CONCLUSION: Although oxytocin in both study groups showed similar efficacy in terms of preventing atonic primary postpartum haemorrhage, participants who received intravenous oxytocin were more likely to require additional uterotonics to reduce their likelihood of having an atonic primary postpartum haemorrhage. However, both routes have similar side effect profiles.