ABSTRACT: Obstetric hemorrhage accounts for ∼25% of maternal morbidity. Many methodologies are used to promote active management of the third stage of labor. Tranexamic acid successfully reduces blood loss and transfusion requirements in nonobstetric conditions. This double-blind, randomized, controlled trial was undertaken to estimate the effects of adding tranexamic acid to an active management protocol.
The parturients were at 34 to 42 weeks’ gestation, with a live fetus in cephalic presentation, and expecting vaginal birth. The experimental group (n = 228) received 1 g/10 mL tranexamic acid diluted with 20 mL 5% glucose; the placebo group (n = 226) received 30mL5%glucose. Tranexamic acid or placebo was administered intravenously over 5 minutes at delivery of the fetus’ anterior shoulder. Standard management of the third and fourth stages of labor was applied. The primary outcome was the volume of blood loss during the third and fourth stages of labor. Other outcomes were the incidence of postpartum hemorrhage (PPH; >500 mL), severe PPH (>1000 mL), need for blood transfusion, need for additional uterotonic drugs, and adverse effects of tranexamic acid. Participants were contacted 3 weeks after delivery to assess the incidence of thromboembolic events. Data were analyzed on an intent-to-treat basis.
The final analysis included 220 and 219 in the tranexamic acid and control groups, respectively. The groups were similar in patient characteristics and risk factors for PPH. At the third and fourth stages of labor, mean estimated blood losses were 261.5 ± 146.8 and 349.98 ± 188.85 mL in the tranexamic acid and control groups, respectively (P < 0.001). Four patients (1.8%) in the tranexamic acid group and 15 (6.8%) in the control group had PPH of greater than 500 mL (RR, 3.76; 95% CI, 1.27–11.15; P = 0.01). Six (2.7%) and 19 (8.7%) women in the tranexamic acid and control groups, respectively, required additional uterotonic agents (RR 3.18; 95% CI, 1.29–7.81; P = 0.007). The groups did not differ in need for blood transfusion. Predelivery hemoglobin and hematocrit levels were the same in the 2 groups, but at 1 day postpartum, hemoglobin levels were 9.9 T 1.4 and 9.3 T 0.9 g/dL (P G 0.001), and hematocrit levels were 30.2% ± 1.2% and 29.0% ± 1.3% (P < 0.001) in the tranexamic acid and placebo groups, respectively. No major complications and no significant changes in prothrombin time, active prothrombin time, or liver or renal function tests were noted in either group. Rates for nausea, vomiting, and diarrhea were 15.0%, 13.6%, and 7.3% in the tranexamic acid group and 5.5%, 6.4%, and 1.8% in the control group. At the clinical checkup 3 weeks postpartum, no episode of thrombosis was reported in patients given tranexamic acid.
Tranexamic acid can reduce the average amount of blood loss during the third and fourth stages of labor. Determining the clinical settings in which this medication may be beneficial is critical for future research.