IMox study
Research type
Research Study
Full title
Intramuscular oxytocics: A multi-centre randomised comparison study of intramuscular Carbetocin, Syntocinon and Syntometrine for the third stage of labour following vaginal birth
IRAS ID
156143
Contact name
Helen Lewis
Contact email
Sponsor organisation
North Bristol NHS TRust
Eudract number
2014-001948-37
Clinicaltrials.gov Identifier
Duration of Study in the UK
1 years, 4 months, 22 days
Research summary
A quarter of all global pregnancy-related deaths occur due to excessive bleeding after childbirth, or “post partum haemorrhage” (PPH). Active Management of the Third Stage of Labour (AMTSL) after vaginal birth, which includes use of a preventative uterotonic drug, reduces the risk of PPH by 66%.
Syntometrine is most commonly used for this purpose in the UK. Syntocinon is the drug which national guidelines recommend first-line. This is because Syntocinon is less likely to cause nausea , vomiting and transient high blood pressure, and is just as effective as Syntometrine at preventing PPH >1000ml. However, Syntometrine is more effective at preventing PPH of 500-1000ml. This is why maternity units still choose to use it, despite the nausea and vomiting experienced by ~25% of patients.
Carbetocin, a newer uterotonic drug already used during caesarean section, is more expensive but potentially more effective. Previous studies suggest that patients receiving Carbetocin may need fewer additional drugs to treat and prevent PPH than those receiving Syntocinon. Compared with Syntometrine, patients receiving Carbetocin lose less blood and experience fewer side effects. No studies have directly compared these three drugs.
This is a double-blind randomised study across four obstetric units in the Southwest of England to directly compare the effectiveness, side effects and cost of intramuscular Syntocinon, Syntometrine and Carbetocin given in the third stage of labour after vaginal birth. 6285 women will be recruited over 16 months. Patients will be randomised to receive one of these three drugs during the third stage of labour. Standard intrapartum care will be adopted leading up to, and after, this single-dosed intervention. The primary outcome measure will be the proportion of women requiring additional uterotonic drugs to treat or prevent PPH. Secondary outcomes will include incidence of PPH, blood transfusion, maternal side effects, health-related quality of life, and cost.
REC name
South Central - Oxford B Research Ethics Committee
REC reference
14/SC/1312
Date of REC Opinion
28 Oct 2014
REC opinion
Further Information Favourable Opinion