A new study in Texas could alter the landscape of the treatment of severe brain injury. The study involves giving a dose of estrogen within a couple of hours of injury, since research suggests that waiting longer significantly reduces the chances of successful treatment of a brain injury. The study will target men because 70 percent of patients with brain injury or blood loss are young males. Studies have suggested young women, who have high amounts of estrogen, are more resistant to brain trauma than men or older women.