Tranexamic Acid for the Prevention of Blood Loss After Vaginal Delivery

The use of tranexamic acid (TXA) reduces mortality in the setting of postpartum hemorrhage (PPH). This study investigated whether the prophylactic administration of TXA in addition to prophylactic oxytocin in women with vaginal delivery would decrease the incidence of PPH. In a multicenter, double-blind, randomized controlled trial, women in labor who had planned a vaginal delivery of a singleton live fetus at 35 or more weeks of gestation were randomly assigned to receive 1 g of TXA or placebo, administered intravenously, in addition to prophylactic oxytocin after delivery. The primary outcome was PPH, defined as blood loss of at least 500 mL, measured with a collector bag. Of the 4079 women who underwent randomization, 3891 had a vaginal delivery. The primary outcome occurred in 156 (8.1%) of 1921 women in the TXA group and in 188 (9.8%) of 1918 in the placebo group (relative risk, 0.83; 95% confidence interval [CI], 0.68-1.01; P = 0.07). Women in the TXA group had a lower rate of provider-assessed clinically significant PPH than those in the placebo group (7.8% vs 10.4%; relative risk, 0.74; 95% CI, 0.61-0.91; P = 0.004, P = 0.04 after adjustment for multiple comparisons post hoc) and also received additional uterotonic agents less often (7.2% vs 9.7%; relative risk, 0.75; 95% CI, 0.61-0.92; P = 0.006, adjusted P = 0.04). Other secondary outcomes did not differ significantly between the 2 groups. The incidence of thromboembolic events in the 3 months after delivery did not differ significantly between the TXA group and the placebo group (0.1% and 0.2%, respectively; relative risk, 0.25; 95% CI, 0.03-2.24). Among women with vaginal delivery who received prophylactic oxytocin, the use of TXA did not result in a difference in the rate of PPH of at least 500 mL as compared with women randomized to placebo.