WASHINGTON -- Staff Sgt. Ross Cox's wounds from the buried bomb were horrific enough: left foot blown off, right leg shattered, three tourniquets strapped to his bleeding limbs.

As he lay in the Afghan dirt Nov. 15, he thought about getting home to his wife and four children. Something else occurred to him. What about his genitals? He'd been wearing just-issued ballistic underwear. Still.

"I asked once, I said, 'Hey, are those OK?' " Cox says. "He's like, " 'Yeah, you're fine. You're fine there.' That's all I needed to know."

Cox, 36, credits the "protective undergarments" or PUGs - "like a Kevlar diaper" - with saving his genitals and preventing bomb fragments from tearing into his crotch and abdomen.

New research backs him up. Without the armored shorts, nearly three in four troops who lost legs to bomb blasts also suffered genital injuries from February 2010 to February 2011, according to the Joint IED Defeat Organization. That dropped to less than half for troops wearing PUGs from February 2011 to last month.

Two types of PUGs have been fielded to troops by the Army. The shorts keep dirt and fine debris from bomb blasts from piercing the skin. A protective cup shields troops from larger fragments.

The Pentagon has spent more than $40 billion to buy Mine Resistant Ambush Protected (MRAP) vehicles to protect troops from roadside bombs. Troops on foot patrol, a common practice in the counterinsurgency effort in Afghanistan, have had little more than their boots and pants between them and a blast. More than 1,440 troops have lost limbs in the wars in Iraq and Afghanistan, according to the Army.

Beyond protecting troops from wounds, PUGs can affect morale, says Jim Martin, a sociologist at Bryn Mawr College in Pennsylvania and a retired Army colonel.

"It conveys a very strong message on the part of the Army and government to give you the best equipment possible," Martin says, "that they're not just concerned about executing the mission but your safety and well being, too."

The Army is fielding new gloves with better protection after reports showed soldiers losing their fingers when bomb debris pierced the fabric, says Lt. Gen. William Phillips, a top Army procurement official.

"Soldier protection is Job No. 1," Phillips said.

Cox and his soldiers from a Stryker brigade from Fort Wainwright in Fairbanks, Alaska, had been skeptical of PUGs when they were issued, about four days before he was wounded. They worried that the underwear would slow them down, chafe and be too hot.

Their attitude changed when an improvised explosive device wounded a soldier from another platoon "that pretty much took the lower half of his body," Cox says. "Had he been wearing that piece of equipment, would it have helped? I don't know."

PUGs were mandatory days later when Cox and his unit were winding their way through a drainage ditch on patrol. About 20 soldiers, some with mine detectors, walked in front of him. Ten or 15 were behind him.

"I stepped on the IED with my left foot, so my left foot was immediately blown off," Cox says. "My right leg shattered out. My calf was completely destroyed on my right side. My bone was shattered. It wasn't broken, it was shattered into a bunch of little pieces.

"On the left side, the blast continued up the back of my leg, past my knee, on hamstrings. Then it continued up to my left buttock. It stopped right above my cheek. The garment that I was wearing stopped everything from literally blowing up my rear."

Cox remained conscious and tried to stay calm. He "went to his own little world," thinking about his wife, Nicole, 35, and their four children: Peyton, 13; Brennan, 9; Hope, 3; and Asher, 2. Within 15 minutes, soldiers had loaded him onto a medevac helicopter.

Hours later, the Army phoned Nicole in Fairbanks.

"Oh, my goodness, I was hysterical," she remembers. "The guy just had woken me up out of bed. I had to catch my breath. You don't ever think it will happen to your husband, a platoon sergeant."

Cox arrived at Brooke Army Medical Center in San Antonio on Nov. 21. Nicole saw him there two days later.

"It was just him," she says. "You know what I'm saying? I was just glad that he was there. We never wanted him to deploy this time. I think deep down we knew something was going to happen. We were both apprehensive about the whole thing."

The couple credit their faith in God and support from family and Army friends for helping them persevere. Cox will retire after his rehabilitation, which could stretch an additional nine months.

They also credit his equipment for saving him from losing more - his genitals or part of his gut.

"This is devastating," Nicole Cox says. "I don't want to downplay what's happening. For anything else to have gone missing? You know what I'm talking about? That would have been a much harder thing to deal with."

Cox hopes his wounds and the ones he was spared help persuade other soldiers to wear PUGs.

"I'm glad that maybe me getting hurt maybe protected some other people, too," he says. "A lot of gear that we have we feel is burdensome. It is ridiculous. But this literally saved my butt."