Table 1.

Comparison of uterotonic drugs used as therapy during major obstetric haemorrhage (MOH). CD, Caesarean delivery; IU, international unit; PPH, postpartum haemorrhage; PR, rectal; PV, vaginal; SL, sublingual.

Uterotonic drug	Indication	Mechanism of action	Recommended dose during MOH for PPH	Major contraindications
Oxytocin	First-line therapy	Via oxytocin receptors on myometrial cell membrane	After vaginal delivery: 5 IU i.v. slowly. Elective Caesarean delivery (CD): bolus 1 IU oxytocin; then infusion at 2.5–7.5 IU h−1. Intrapartum CD: 3 IU oxytocin over ≥30 s; then infusion at 7.5–15 IU h−1. If required after 2 min after initial bolus, give a further dose of 3 IU over ≥30 s.	Extreme caution in context of haemodynamic instability or cardiovascular disease – deliver drug slowly
Carbetocin	First-line therapy	Via oxytocin receptors on myometrial cell membrane	After vaginal delivery: 100 μg over ≥30 s. Elective CD: 100 μg over ≥30 s. Intrapartum CD: 100 μg over ≥30 s. Smaller doses may be sufficient at CD (as low as 20 μg) and may be repeated up to 100 μg. Do not exceed 100 μg in any setting.	Extreme caution in context of haemodynamic instability or cardiovascular disease – deliver drug slowly
Prostaglandins	Second-line therapy: misoprostol may be used as first line where oxytocin/carbetocin unavailable	Via prostaglandin receptors PGE1, PGE2, and PGF2α subtypes	Misoprostol 400–600 μg: sublingual, rectal, vaginal, oral; repeat after 15 min if required, maximum dose 800 μg. Carboprost 250 μg: i.m. or intramyometrial (contraindicated i.v.); up to every 15 min if required, maximum eight doses. Sulprostone 500 μg: i.v. at 100 μg h−1; maximum dose 1500 μg.	Asthma/obstructive lung disease
Ergot alkaloids	Second-line therapy	Via dopamine, α-adrenergic and 5-HT3 receptors	Ergometrine (ergonovine) 200–500 i.m. or slow i.v. in exceptional circumstances; may be repeated after 2 h.	Hypertension Myocardial ischaemia Cardiovascular disease