The efficacy of tranexamic acid for the prevention of postpartum hemorrhage among women at high risk of postpartum hemorrhage undergoing cesarean section: a meta-analysis.

OBJECTIVES

This meta-analysis investigated the extent to which tranexamic acid reduces the risk of postpartum bleeding among pregnant women at high risk of postpartum hemorrhage undergoing cesarean section.

METHODS

Scopus, the Cochrane Library, PubMed, and Web of Science were searched from their establishment to December 4, 2025, to identify randomized controlled trials comparing tranexamic acid with placebo for preventing postpartum hemorrhage in high-risk women undergoing cesarean section. Because of high heterogeneity, we employed a random-effects model (restricted maximum-likelihood) to pool data.

RESULTS

Finally, 12 articles with 1240 high-risk pregnant women were included in this meta-analysis. Compared to placebo, tranexamic acid significantly reduced blood loss after cesarean delivery in high-risk pregnant women (WMD - 435.44 mL, 95% CI (-581.86, -289.01) I2 = 94.71%). Furthermore, tranexamic acid significantly prevented the drop in hemoglobin level (WMD 1.09 g/dL, 95% CI (0.20, 1.99) I2 = 97.63%), prevented postpartum hemorrhage (RR 0.45, 95% CI (0.30, 0.70) I2 = 49.34%) and more than 1000 mL blood loss (RR 0.23, 95% CI (0.14, 0.37) I2 = 0.00%), and reduced the need for transfusion (RR 0.28, 95% CI (0.20, 0.39) I2 = 0.00%) and uterogenic agents (WMD 0.28, 95% CI (0.18, 0.46) I2 = 85.63%). The beneficial effects of tranexamic acid on the length of hospital stay (WMD - 0.46 days, 95% CI (-0.93, 0.01) I2 = 73.44%) and the length of surgery (WMD - 8.20 min, 95% CI (-17.15, 0.74) I2 = 96.28%) did not reach the threshold of statistical significance. Compared to the placebo group, nausea/vomiting was significantly more frequent in the tranexamic acid group (RR 1.89, 95% CI (1.02, 3.52) I2 = 0.00%), while dizziness (RR 1.13, 95% CI (0.32, 3.92) I2 = 16.09%) and headache (RR 1.85, 95% CI (0.48, 7.19) I2 = 25.87%) showed no significant. There was no case of thromboembolic events in either group. Exploratory subgroup analysis showed that sample size, risk of bias, mother's body mass index (BMI), tranexamic acid dose, the timing of administration, gestational age, and the reason for being high-risk significantly affected the beneficial effects of tranexamic acid on the volume of blood loss.

CONCLUSION

Our findings suggest that tranexamic acid may effectively reduce bleeding among women with a high risk of postpartum hemorrhage undergoing cesarean section.