An inexpensive generic drug that saves the lives of wounded soldiers and civilian car crash victims has now been shown to rescue women suffering hemorrhages in childbirth.

Postpartum hemorrhage, in which women bleed uncontrollably after childbirth, kills an estimated 100,000 women a year in poor and middle-income countries. The complication also forces doctors to perform emergency hysterectomies, especially when hospitals have too little blood on hand to provide transfusions.

In a major six-year trial involving over 20,000 women in 21 countries, researchers showed that tranexamic acid, a little-known blood-clotter invented in the 1950s, reduced maternal bleeding deaths by a third if it was given within three hours. It costs less than $2 a dose and does not require refrigeration.

The trial — known as Woman, short for World Maternal Antifibrinolytic — was led by doctors at the London School of Hygiene and Tropical Medicine and paid for by the Wellcome Trust, Pfizer, Britain’s health department and the Bill and Melinda Gates Foundation. Results were published in The Lancet on Wednesday.