DALLAS – An intravenous drug administered to women along with oxytocin after vaginal delivery did not reduce the risk of a large-volume hemorrhage, but it did significantly affect some other markers of postpartum blood loss.
The TRAAP trial failed to achieve its primary endpoint – reduction of postpartum hemorrhage of at least 500 ml, Loïc Sentilhes, MD, reported at the meeting sponsored by the Society for Maternal-Fetal Medicine. But tranexamic acid’s success in the prespecified secondary endpoints suggests there still may be a place for the drug in obstetrics, said Dr. Sentilhes of the University Hospital of Bordeaux, France.
“Tranexamic acid was associated with a significant reduction of bleeding that was assessed as clinically significant, and it reduced the need for other uterotonics,” said Dr. Sentilhes. “It was also safe, as the risk of vascular occlusive events in the 3 months after delivery did not differ from placebo.”TRAAP randomized 4,079 women in labor for a planned vaginal birth to either 1 g of tranexamic acid or placebo. The interventions were added to existing IV fluids within 2 minutes after vaginal birth, after the women had also received routine oxytocin.
The study’s primary outcome was the incidence of postpartum hemorrhage, defined as a blood loss of 500 ml or more. There were a number of prespecified secondary outcomes, including clinically significant blood loss, need for additional uterotonics, severe hemorrhage (more than 1,000 mL), estimated total blood loss, transfusion, and changes in hemoglobin and hematocrit.
The study also looked at these outcomes in prespecified subgroups: women who had an episiotomy, who had an operative delivery, and who had a history of prior postpartum hemorrhage.
Women in the study were a mean age of 30 years; about half were primiparous, and 5% were attempting a vaginal birth after cesarean section. Of the women, 4% had experienced a prior postpartum hemorrhage. Labor was induced in 20%, and about 60% needed labor augmentation.
An operative vaginal delivery was necessary for 17%. Forms of assistance included forceps (55%) and vacuum extraction (45%). About a quarter had an episiotomy, and 8% had a macrosomic neonate of more than 4,000 g.
The primary endpoint of at least 500 ml blood loss occurred in 8.1% of the active group and 9.8% of the placebo group – a nonsignificant difference (relative risk, 0.83; P = .07).
Of the secondary endpoints, only two – clinically significant bleeding and need for additional uterotonics – were significantly better in the tranexamic acid group. The drug reduced the risk of clinically significant bleeding by 26% (RR, 0.74; P = .004) and the need for additional uterotonics by 25% (RR, 0.75; P = .006).
While the primary endpoint was not realized in the overall patient group, tranexamic acid achieved barely significant risk reductions of 34% in the risk of hemorrhage among women who had an operative delivery (RR, 0.66; P = .0498) and 27% among those who had an episiotomy (RR, 0.73; P = .049).
It was no better than placebo in women with a history of postpartum hemorrhage.
Those who received the drug were twice as likely to experience nausea and vomiting after delivery as did those who received placebo. But tranexamic acid exerted no lingering prothrombotic effects at 3 months after delivery, with no signals in deep vein thrombosis, no pulmonary embolism, and no clots in the ovarian or superficial veins.
The TRAAP trial was funded by the French Ministry of Health under its clinical research hospital program. Dr. Sentilhes had no financial disclosures.
SOURCE: Sentilhes L et al. Am J Obstet Gynecol. 2018;218:S1.