Since the WOMAN trial, intravenous tranexamic acid (TXA) has been increasingly used in severe postpartum haemorrhage (PPH) but research evaluating use in high-income settings is limited. To assess whether implementation of a new guideline involving early administration of 1 g intravenous TXA in active PPH with blood loss ≥1000 mL, was associated with a change in maternal morbidity. Retrospective study of all singleton, term, vaginal births from November 2016 to June 2019 with a PPH of ≥1000 mL, before and after hospital adoption of a guideline recommending early (within three hours of birth) administration of TXA for women with active PPH ≥1000 mL. Univariate analysis assessed the impact of this guideline implementation on a primary outcome of maternal morbidity, defined as one or more of haemoglobin <90g/L, administration of blood products, hysterectomy or intensive care admission. Secondary outcomes were adverse events related to administration of TXA, use of an intrauterine balloon or postpartum iron infusion. There was no difference in morbidity (odds ratio (OR) 0.86, 95% CI 0.57-1.29, P=0.46) or postpartum iron infusion (OR 1.44, 95% CI 0.92-2.27, P=0.11), but there was a reduction in the use of intrauterine balloon tamponade after the implementation of the TXA guideline (OR 0.33, 95% CI 0.16-0.67, P<0.01). This retrospective analysis showed a reduced use of intrauterine balloon but failed to show a benefit in maternal morbidity with early administration of TXA for severe postpartum haemorrhage in a high-income setting.