A 60-unit oxytocin hour was linked to fewer haemorrhages after vaginal birth

Design

Single-centre quality-improvement study, before vs after protocol change

Population

2,674 births (1,309 before, 1,365 after), excluding accreta and births before 24 weeks

Primary outcome

Postpartum haemorrhage, quantitative blood loss ≥1,000 mL

Effect

11.2% vs 14.3%, aRR 0.77 (95% CI 0.64–0.93); vaginal births aRR 0.60 (0.42–0.86); caesarean aRR 0.89 (0.71–1.11)

A US maternity unit changed its third-stage protocol from 30 units of oxytocin over one hour (then a low-rate maintenance infusion) to 60 units over one hour, and compared about 1,300 births on each side of the change in the first half of 2024. Blood loss was measured quantitatively, and haemorrhage was defined as 1,000 mL or more.

Haemorrhage fell from 14.3% to 11.2% after the change (adjusted RR 0.77). The whole of that effect sat in vaginal births, where rates fell from 8.5% to 5.2%. Among caesarean births the difference was small and not statistically clear. Median blood loss fell by about 40 mL, which matters less than the shift at the tail.

This is a before-and-after quality-improvement study in one hospital, published in June 2026. Staff training and new pump settings arrived with the new dose, so the dose cannot be separated from the attention that came with it, and other secular changes could contribute. It is a reason to look at your own unit's third-stage protocol and haemorrhage data, not to change doses on the strength of one site.

• Know your unit's current third-stage oxytocin dose and infusion rate, and how it compares with a 60-unit-per-hour protocol.
• Measure blood loss quantitatively; a protocol change cannot be judged on estimated loss.
• The signal was in vaginal births only; do not expect the same gain at caesarean from dose alone.
• If you change a protocol, audit haemorrhage before and after, as this unit did.
• Watch for oxytocin's dose-related effects, including hypotension and fluid load, when rates rise.

Why it matters

A drug every labour ward already uses may be underdosed in the third stage.

Don't overread it

A single-unit before-and-after comparison cannot separate the dose from the training that came with it.

The statistics, in plain English

An adjusted relative risk of 0.77 means about a quarter fewer haemorrhages after the change, and the confidence interval (0.64–0.93) stays below 1, so chance alone is an unlikely explanation. For caesarean births the interval (0.71–1.11) crosses 1, which means no difference is entirely compatible with the data. Before-and-after designs cannot rule out other changes that happened at the same time.

Read the rest in the app

You have read your two free briefings this month. The app carries all 27 specialties, every morning, free — and this finding is waiting in it.

Get Daily Doctor — free

Scan to keep reading on your phone. No account needed to start.