Heavy bleeding after childbirth, known as a postpartum haemorrhage (PPH), causes about 70,000 maternal deaths every year. Tranexamic acid (TXA) is a lifesaving treatment for women with PPH. The I'M WOMAN trial is a research study to see whether giving TXA just before childbirth will stop women developing PPH. The trial will assess the effects of intramuscular (IM) and intravenous (IV) tranexamic acid on PPH, side effects and other important maternal health outcomes.

Postpartum haemorrhage (PPH) causes about 70,000 maternal deaths every year. Tranexamic acid (TXA) is a lifesaving treatment for women with PPH. The WOMAN trial recruited over 20,000 women with PPH and found that intravenous (IV) TXA given soon after PPH onset, reduces bleeding deaths by about a third. Early TXA also reduces blood loss in surgery and death due to bleeding after traumatic injury. The World Health Organization recommends that all women with PPH should receive TXA as a first line treatment.

TXA is more effective when given soon after the bleeding starts. Every fifteen minute delay reduces the survival benefit by about 10%. This suggests that giving TXA around the time of childbirth might prevent PPH. Although several clinical trials have examined the effectiveness of TXA for the prevention of PPH, the results are inconclusive. Trials of tranexamic acid for PPH prevention give the trial treatment after cord clamping, which may be too late to prevent bad bleeding in some women, as bleeding tends to happen soon after childbirth. Because PPH only affects a small proportion of births, the healthcare community need good evidence on the balance of benefits and harms in this population before using TXA to prevent PPH.

The I'M WOMAN trial will evaluate the effects of TXA for PPH prevention in women with one or more risk factors for PPH having a vaginal or caesarean birth. The trial will also evaluate the effect of the route of TXA administration. TXA is usually given by slow IV injection. However, recent research shows that TXA is well tolerated and rapidly absorbed after IM injection, achieving therapeutic blood levels within minutes of injection. There may be fewer side effects with IM TXA because peak blood concentrations are lower than with the IV route, as well as practical advantages.

Inclusion Criteria:

• Women aged 18 years or older who are admitted to hospital to give birth vaginally or by caesarean section, who have one or more known risk factors for PPH

Exclusion Criteria:

• Women who have a clear indication or contraindication for TXA

The investigators are committed to sharing data for ethical research with justified scientific objectives. Until all planned analyses are completed by the LSHTM CTU Global Health Trials Group, data will be shared through a controlled access approach whereby researchers can make formal applications for data sharing. Afterwards, the anonymised dataset will be shared via the LSHTM CTU Global Health Trials Group data sharing platform at freebird.lshtm.ac.uk. All trial materials including training materials, CRFs and Protocol will be made available on the trial website and team YouTube channel.

Once all planned analyses are completed by the LSHTM CTU Global Health Trials Group following trial completion. Data will be shared indefinitely.

As above

Masking done by an independent clinical trials supply company. It will involve the removal of the original manufacturer's label and replacement with the clinical trial label bearing the randomisation number, which will be used as the pack identification. Apart from the randomisation number, all pack label texts and ampoules will be identical for each arm