Background: many factors are attributed in the management of postpartum hemorrhage after vaginal delivery Objective: to assess the efficacy and safety of a single large dose of intravenous tranexamic acid in reducing postpartum blood loss after vaginal delivery. Subjects and Methods: this is a multicentric prospective randomized double blind placebo controlled trial. 240 pregnant women were randomized to receive either 60 mg/kg of TA (n=120) or placebo (n=120) intravenously in the second stage of labour. Postpartum blood loss was collected and measured accurately from placental delivery to 2 hours postpartum and adverse effects of were observed.                        Results: the mean estimated postpartum blood loss was significantly lower in women treated with tranexamic acid compared to women in the placebo group (241.5 ± 82.7 versus 322.8 ± 127.4, respectively; p < 0.001), and the proportion of women in the tranexamic acid group who had an estimated blood loss  ≥ 500 mL was significantly lower than in the placebo group ( 5 [4.2%] versus 18 [15%], relative risk [RR]=0.30; 95% confidence interval [CI] 0.11 to 0.78; P<0.05). Maternal and neonatal outcomes did not differ significantly between both groups.                    Conclusion: A single large dose of tranexamic acid administrated intravenously before vaginal delivery significantly reduces the amount of postpartum blood loss and contributes to prevention of PPH. Adverse effects were only mild and transient. Thus, tranexamic acid can be used safely and effectively to reduce bleeding after vaginal delivery.