Male soldiers might be able to survive potentially fatal blood loss, if they make their bodies a little more feminine.

That's the finding of the latest research from the University of Alabama at Birmingham. The Department of Defense is so wowed, it has given the researchers $10 million to figure out how.

The discovery began as a happy accident when Dr. Irshad Chaudry ordered a shipment of male mice and got a shipment of female ones instead. At first, he was going to send them back (female mice tend to be tougher research subjects because their hormonal levels fluctuate more), but he decided to keep them and try his study anyway.

The research was on sepsis, a catch-all term for when any infection, including that of an internal organ, releases chemicals into the bloodstream that infect the entire body, inflaming multiple organs and often causing them to fail. It's not a long journey from sepsis to death.

Chaudry went forward with the experiment, attempting to give the female mice sepsis, but he couldn't. The mice were virtually immune to sepsis and its fatal descendant, septic shock. Could it be that female mice are somehow resistant to sepsis? That didn't seem right; after all, human women die from sepsis all the time. If the female mice were immune, it would mean that the mice were very different from humans.

So Chaudry tried again, with a new group of female mice. These mice all succumbed to sepsis. How could the results be so diametrically opposed?

Chaudry and his research assistant, Rene Zellweger (no, not that Renée Zellweger), struck gold when they examined the mice's hormonal cycles. The first shipment had been of mice who, coincidentally, were at the peak of their hormonal cycles (ovulation). The mice in the second shipment weren't. The spike in estrogen was affecting the immune system and the cardiovascular responses, somehow protecting the animals from the deadly infection. So, they tried injecting synthetic estrogen into male and female mice who had undergone trauma.

Most of the mice survived.

In fact, the mice could survive for three hours without any extra fluid, even if they had suffered blood loss. And up to 80 percent could survive for double that: six hours. That was a pretty massive window to get the animals (or a soldier) help.

Chaudry and his lab are now working with the Department of Defense to get the drugs to human trials so that they may be used by soldiers. Ideally, servicemen and -women would carry around syringes full of estrogen, to give to themselves or a wounded comrade. Currently, about 86 percent of combat soldiers are male, making them particularly vulnerable to sepsis, though clearly both male and female soliders could potentially benefit from an estrogen bump in times of trauma and blood loss.

"If these study findings translate to the battlefield," said Chaudry, "additional time will be available for transport of the wounded to safer locations where standard resuscitation measures can be accomplished."

Currently, more than 80 percent of possibly preventable deaths in battle are due to blood loss.

Photo: Brandon Moreno and 1st Armored Division Public Affairs Office | Flickr