Before they went off to fight in Afghanistan, the guys of 3rd Battalion, 5th Marines talked quietly about their deepest fear. Not dying. Not losing a leg or an arm.

It was having their genitals ripped off, burned away or crushed in the fiery blast of an improvised explosive device.

This was no idle concern to young men bursting with testosterone. The makeshift bombs known as IEDs are taking a frightening toll in Afghanistan, the blasts shearing off arms and legs, ripping through soft flesh, crushing organs and bone, and driving dirt, rocks and filth deep into torn flesh -- often leaving the genitals shredded or missing. Some guys said they'd rather be dead.

Mark Litynski, a 23-year-old rifleman with Lima Company, knew the odds. He'd been married to Heather for almost a year, and children were in the future they planned together.

I ought to freeze my sperm so we could still have kids if something happened, he thought.

The idea nagged at him. But in the rush of last-minute training before they packed their sea bags and weapons and then took a few days of boisterous leave, he kept putting it off. Where do you go to freeze your sperm, anyway? Who would you even ask?

By the time they loaded on the buses at Camp Pendleton, it was too late. Should have done it, Mark thought as they boarded the plane in September 2010.

Weeks later, Mark was on a combat patrol in Sangin, southern Afghanistan, walking behind an engineer sweeping for IEDs, marking their path with yellow spraypaint. IED detectors aren't foolproof. There came a bright flash and searing heat, then the upward blast ripped off both of Mark's legs and most of his left arm, slashing into his remaining arm, shattering his pelvis and driving a rock and other debris up into his abdominal cavity.

Amid the bloody carnage, all the skin was ripped from his penis and his testicles were gone.

Days later, after trauma surgeons in Germany finished trimming and suturing his stumps and temporarily closing his abdominal wounds, he managed to say a few words to Heather on the phone.

"I'm so sorry," he croaked.

“I love you,'' she told him, blinking back tears. "We will pull through this together, as a team.''

'THEY WEREN'T PREPARED FOR THIS'

The decade of U.S. combat in Afghanistan has left Afghans and Americans with a seemingly endless series of woes. But among the most devastating are the blast wounds that have left more than 16,000 young Americans severely wounded.

Several hundred have suffered genital injuries in addition to amputations and burns, leaving them unable to father children and struggling to engage in something resembling the sex they used to have, often without the aid of what many view as the primary symbol of their manhood.

"Who's going to want to be with me now?'' wondered Marine Staff Sgt. Glen Silva, 39, after an IED blast shattered his leg, ripped open his lower torso and severed most of his penis.

It was a legitimate concern. Silva's girlfriend stayed with him at Walter Reed National Military Medical Center in Bethesda, Md., through many of his 42 surgeries. But one day he was wheeled back to his room to find she had gone, leaving a nine-word handwritten note: "I can't take this any more. I'm outta here."

Silva, the Litynskis and others agreed to share the painful and intimate details of their ordeals in order to spotlight what they feel is a life-altering but often hidden wound, one that is frequently given inadequate attention and care within the military health care system. Those who cannot regain their sexual function or drive are given little understanding or aid, they say. In Mark and Heather's case, it took the intervention of The Huffington Post to get them an appointment with Walter Reed's specialist in sexual dysfunction.

"They weren't prepared for this,'' Silva said of the Walter Reed staff.

Since 2005, more than 1,500 soldiers and Marines have been carried off the battlefield with genital wounds. But since late 2009, when President Barack Obama ordered a "surge'' of 30,000 combat troops into Afghanistan and approved a new tactic of increased foot patrols, the pace of genital injuries has accelerated.

In the year before the surge, 170 combat troops suffered genital wounds, mostly from IED blasts. In 2010, according to Pentagon data, that number leapt to 259. Last year, the Defense Department counted 299 cases of genital wounds that James Jezior, a urologist who does genital repair surgery at Walter Reed, characterizes as "devastating.''

"I remember lying on my side, dust everywhere, and I looked down and saw my arms were split open and squirting blood and I had just two bloody stumps above my knees," said Marine 1st Lt. James Byler, 26, who was blown up a few weeks before Mark Litynski. "My first coherent words to my Marines were, 'Hey! check my nuts!'" His genitals were severely damaged, but intact.

"It's the male instinct, the first thing you care about,'' Byler said. "In past wars, guys didn't live if they got injured as badly as me, but we've gotten so good at the medevac process now that guys who are catastrophically wounded are surviving. Now you have all these further complications -- like, you know, what's going to happen with my genital wounds?''

Military surgeons and specialists acknowledge that they often don't know the answer, because, until recently, they had little or no exposure to such injuries.

'I AIN'T GOING TO NO SEX-CHANGE DOCTOR'

In past wars, most casualties were head and chest wounds caused by shrapnel from mortars and artillery or from bullets. Walter Reed, the nation's premier military hospital, attracts some of the best talent in military medicine. But doctors there say their only relevant experience with sexual dysfunction had long been with older prostate cancer patients, who obviously have vastly different medical and psychological needs than young men with severe battle injuries.

During the past decade, IED blasts have become the primary cause of U.S. battle casualties, killing or wounding 34,360 American troops in Iraq and Afghanistan, according to the most recent Pentagon data. One reason for the increasing incidence is that modern body armor protects the chest but leaves the lower torso exposed to the upward blast of buried bombs, a vulnerability that insurgents have exploited.

Many victims end up at Walter Reed, where surgeons are able to repair some damage to the penis. Jezior uses tissue he cuts from inside the patient's cheek or lip to rebuild the urethra, which carries urine through the penis from the bladder. Oral tissue is used because it is hairless and used to being wet, Jezior explained, and is rolled into a tube to replace the damaged urethra. He grafts skin from the patient's thigh or groin to rebuild the outer layer of the penis.

But for guys like Staff Sgt. Silva whose penises have been partly or totally destroyed, options are few. Expertise within the military on penis replacement, or phalloplasty, is so limited that some Walter Reed patients have been referred to civilian surgeons who specialize in sex-change operations. It's an option not well received in the ranks.

"I ain't going to no sex-change doctor,'' Silva growled. Besides, he had seen photos of the penises they had made with surgical flaps from patients' forearms. "I could do better with Silly Putty," he snorted.

But there is hope that doctors may soon be able to regrow a penis from the smooth muscle and endothelial cells of patients like Silva. Advances in regenerative medicine have surged during the past decade. At the Wake Forest Institute for Regenerative Medicine, a team led by Anthony Atala reported last year that they had regenerated the penises of 12 New Zealand white rabbits. Once they healed, the rabbits were placed in cages with female rabbits. All attempted copulation within one minute and four females became impregnated.

Can he grow a penis for Silva? "We are always cautiously optimistic. This still requires a lot of work to make sure it works well,'' Atala said in an interview. "As much as it works in the laboratory, it may not work in the human."

"But," he added, "we have a good history. Hopefully this holds some promise for the future."

Atala is seeking regulatory approval to begin experimental penile regeneration in humans. He has met with Silva to discuss the procedure and said he wants to move forward "as expeditiously as possible," though he declined to provide a more specific timeframe.

Still, even if surgeons can physically rebuild genitals, making them work effectively and pleasurably is vastly more challenging. Achieving erection, orgasm and ejaculation involves a complex interplay of sensory nerves, muscles and blood-vessel functions, any or all of which may have been damaged by an IED blast.

"Even if you can regenerate tissue, it doesn't mean you can make that tissue function exactly the way it did before -- mostly because of nerve function,'' said Robert Dean, an andrologist who is Walter Reed's lone specialist in sexual dysfunction.

'WHO'S GOING TO WANT TO BE WITH ME?'

A genital wound doesn't mean the end of pleasurable or productive sex, however, according to Dean and other specialists. It's a common misconception, Dean said, that sex must include an erection, orgasm and ejaculation. "After an injury, the ejaculation function may be gone, but orgasm isn't," he said. "Erections may be difficult to achieve, but orgasms are still possible."

That's the theory. But predicting how well individual genital-wound patients will recover is nearly impossible, doctors admit.

Much is unknown about the secondary effects of a powerful blast on human organs. Apart from the obvious physical damage, the concussive blast wave seems to affect sexual function in ways that are not clear. Byler, for instance, suffered little visible physical damage to his genitals, but his testosterone levels and sperm count dropped alarmingly after he was injured.

He and many other genital-wound patients are given replacement doses of testosterone. Low testosterone levels can depress sex drive and decrease energy levels, but the treatment often requires precise dosages and a lengthy process of trial and error. And often, its effects are masked, as many patients are also taking a cocktail of other drugs for pain and anxiety or to control swelling and fight infection.

It's a situation that breeds intense frustration. Genital-wound patients are anxious to know what their sexual future looks like. But doctors at Walter Reed often are unable to reassure them that their sexual functions will ever return in whole, in part or at all. It can take a year, even two, for answers to begin to emerge, Jezior said.

Even then, he said, "We absolutely do not know how well their reactions will be with what they have remaining, how functional they will be. It takes a lot of time to heal, a lot of recovery, every part of the body has to heal before your erections become what will be their end-state.''

Some patients, he added, "will not get back to a functional state.''

But it can be difficult to determine who will recover, and how much, medical officials said, largely because there is a relative paucity of data on the long-term medical and psychological effects of the available treatments and the wounds themselves.

That uncertainty can add yet another crushing psychological burden for young men already struggling with the loss of arms and legs.

"You hear a lot of, 'This is the best we can do, but the fact of the matter is, we have never seen this type of injury before, so we [doctors] really don't know what to tell you,'" said Byler, speaking of his experience as an amputee and genital-injury patient at Walter Reed.

Byler said he never even saw a urologist until four or five months after he was wounded. "There's a lot of things they can do for limbs that are lost, like my legs -- but no one really addresses the genitalia,” he said. “You need someone to come look at the damage and give you an honest assessment of what they think it's gonna be. Because otherwise you're left wondering, who's going to want me? Who's going to want to be with me?''

Doctors at Walter Reed acknowledge having long failed to recognize that while young men may accept the loss of a limb, even the loss of several limbs, they are often far more devastated by damage to their genitals.

"There certainly was a disconnect," said Jezior. "It was an eye-opener for us that there is a grieving when it comes to significant injury to the genitalia that needs to be dealt with.'' Still, he insisted that the care provided to genital wound patients at Walter Reed is "pretty incredible, with a lot of support.''

'WE SAVED HIS PENIS'

Mark and Heather Litynski, however, did not feel supported after Mark was wounded. Their experience was bitter, frustrating and far from the future they had imagined.

They grew up two miles apart in the Minneapolis suburb of New Hope. When Mark shipped out to Afghanistan in September 2010, Heather went home to wait for his return.

She was holding down a temporary job at Starbucks in November when two Marines arrived, accompanied by her mother and sister. Mark was alive, they told her, but in critical condition with "severe lower torso injuries.'' They handed her a terse medical report describing his wounds. When she read "bilateral [both legs] above-knee amputations," Heather collapsed to the ground in shock.

It was far worse than she had feared. But he was alive.

"When I found out, I started crying, but very quickly I got over it because you're just so glad they're alive and doing well," Heather said.

Two days passed, an agony of waiting, before doctors could talk to Heather about the extent of Mark's injuries. There were a lot of other things to worry about -- the potential for deadly infection, of possible brain damage, the trauma of losing two legs and his arm. But one thing the doctors said hit home: "We saved his penis!''

"'Saved his penis!' Got something!" Heather recalled with a chuckle.

Mark has also accepted his wound, just as he has gotten used to his wheelchair, his prosthetic legs and mechanical arm. "When I found out about it [his testicle loss] I was kind of ... you know, 'Should have done the sperm-freeze thing,''' he said. "But ... we're making it through. It's not the end of the world.''

Of course, it wasn't as simple as that.

As surgeons at Walter Reed were working to repair Mark's abdominal wounds and shape his leg and arm stumps, they also began reconstructive work on his penis. They prescribed doses of Viagra or Cialis to see if he could get an erection. A duty nurse administered the first dose while Mark had a full-length catheter inserted in his penis. His erection was painful.

But stimulation is necessary and common early therapy for genital-wound patients, said Dean, the hospital's sexual-dysfunction specialist. "Even though they are not really close to wanting to use it, because they have physical therapy to go through and pain issues, we start rehab therapy to see what effect that has, because we don't want the [penile] tissues to atrophy,'' he said.

Severely wounded patients like Mark typically spend a few months in intensive care at Walter Reed. Then they transfer to an apartment in one of the comfortable new housing units at the hospital and continue their physical and occupational therapy as outpatients. Once Mark got a set of prosthetic arms and learned to walk on his new prosthetic legs, he joined other wounded patients on fishing trips, even a snowboarding in Vail, Colo., just over a year after his injury.

Things weren't easy, though. "He was very affectionate before, he used to always have his arm around me, hold my hand, just come by and kiss my head,'' said Heather. "That's how he was.'' But as his physical wounds healed, the couple's sense of intimacy did not return. Nor did Mark's sex drive. He was lethargic. He had ''zero'' desire, she said.

Mark was taking testosterone to replace the hormone normally produced by his testicles. Heather suspected the dosage was wrong, but she couldn't get anyone at Walter Reed to listen.

"Every time we'd go to the doctor, it was always kind of awkward and embarrassing,'' she said. "I'd have to bring it up and ask them -- they never asked us. I was always given a vague answer -- 'Oh, well, he's still on some medications that can decrease the libido ...' And I'm thinking having sex once every couple of months with your spouse is more than a little 'decrease' in libido."

Heather started wondering if Mark was suffering from traumatic brain injury or post-traumatic stress, but she felt there was no one who had answers or even seemed to care. The frustration inevitably strained their marriage. Out of guilt, Mark began fiddling around with his testosterone patches, trying to adjust the dosage, desperately hoping to find a way to help.

"All of our complaints to his primary care doctors, his urologist -- nothing got us anywhere,'' Heather said. Then, as a result of an interview with The Huffington Post, they made contact with Dean.

In a January interview, Dean had enthusiastically described his work with genital-wound patients and their spouses. "We address how you are going to walk and dress yourself, how you're going to have sex in the future and how you're going to have children in the future, if possible,'' he said.

A few weeks later, I mentioned Dean and his work to Mark and Heather, and was astonished to learn that they had never heard of him, despite having lived in his hospital for 15 months. Before they heard about Dean, Heather said, "I was never referred to any doctor that could really help us.''

Within days, they met with Dean, who ran some tests and ordered a change in Mark's testosterone therapy. He expects dramatic improvement.

But the Litynskis' disappointments haven't ended.

'IT JUST DOESN'T SEEM RIGHT'

The Pentagon, alarmed at the rising incidence of genital wounds, has rushed $19 million worth of protective garments to Afghanistan, including 165,000 pairs of blast-resistant briefs and 45,000 diaper-like garments to protect the genitals from upward blast..

For those who have already suffered genital wounds, there is less help.

Couples like Mark and Heather, who want the option of natural childbirth, can turn to in vitro fertilization, using donor sperm. But the process is expensive, well beyond the means of typical enlisted soldiers and Marines. At Walter Reed, the cost of a single in vitro procedure runs from $4,800 to $7,000, and success may require many attempts.

Yet the military's medical insurance program, Tricare, specifically excludes coverage for the procedure, even in cases where the husband's reproductive organs have been destroyed in combat.

The Department of Veterans Affairs has added to the frustration. Through its insurance program, the VA pays up to $100,000 to the severely wounded to compensate for loss of income and to help finance cars adapted for their use and other new needs. Late last year, the VA also agreed to pay up to $50,000 for damage to or loss of genitals in combat, but its $100,000 lifetime cap on such compensation does not account for veterans who have been wounded as catastrophically as Mark Litynski.

Along with many others severely wounded in combat, Mark has been awarded the full $100,000 for the loss of both legs. Because of the cap, however, he will not receive the additional $50,000 for his genital wounds -- money that could help pay for fertility treatment or adoption.

Defense Department officials repeatedly refused, over a period of several months, to respond to The Huffington Post's questions about the limits on compensation or gaps in care for those with genital wounds. Finally, Pentagon spokeswoman Cynthia Smith said in a statement that the department is "working to provide" reproductive services "to severely injured service members without additional costs to them."

Smith was unable to provide details. Heather Litynski said she has not been contacted by anyone in the Defense Department offering to help pay for fertility procedures.

Considering that Mark volunteered to serve his country and was severely injured in that duty, "it seems like it should be up to the government'' to compensate them, Heather said, for not being able to have their own children together.

"It just doesn't seem right,'' added Heather, a registered nurse who typically has a sunny disposition and a quick smile. She and Mark had long planned to have children. But adoption is expensive. And apart from being costly, there are some aspects of artificial insemination or in vitro fertilization that can be hard for some couples to accept.

"It may be difficult using another man's sperm,'' she said. "The idea does bother me sometimes." And having their insurance refuse to pay for it "is pretty disappointing,'' she added.

Last year, the U.S. Army's surgeon general commissioned a study of blast injuries, including genital wounds, and concluded that military care has lagged behind. "These are complex problems that are not commonly seen in civilian life,'' said Army Col. Jonathan Jaffin, a trauma surgeon who directs the Army's Dismounted Complex Blast Injury Task Force, which was established to improve the treatment of the severely wounded.

Like many others, Jaffin acknowledged that the military has fallen short, that it cannot fully answer the questions of couples like Mark and Heather Litynski, let alone resolve their problems. "We're trying to gather data but we don't have a good answer as to all of the problems we're seeing,'' he said. Genital wounds, he said, are "a very difficult problem, not just a physical problem but one that involves the family, the social dynamics, psychological and spiritual aspects."

"We are doing everything we can to provide the very best care" for the severely wounded, Jaffin added. "I don't think any of us will ever say we have the complete solution. We're going to have to keep pushing, keep making it better."

'I WOULDN'T CHANGE IT FOR ANYTHING'

Mark and Heather are still living at Walter Reed, hoping Mark's new hormone treatments will help ease the strain in their relationship. Yet despite their ordeals, they both seem determinedly upbeat and ready to take on the next phase of their life. Soon they'll move back to New Hope, Minn. Heather will look for work as a nurse while Mark goes back to school to study business.

And they are weighing the costs and benefits of in vitro fertilization, artificial insemination and adoption.

"We definitely want to have children. It's going to be a big expense for us," Heather said. "It is disappointing to me -- so much has been done and given to us because of his combat injuries, which is wonderful. I feel the care and concern from the public and different charities and organizations -- it's so much, it is overwhelming.

"But there is the huge gap in alternative family planning. There's no compensation, no help. There are charities that offer to help but I'm thinking it should be the responsibility of the government."

They will struggle ahead, she said. But their lives will be different from what they had anticipated just two years ago. "Yes, it is different, but it's still livable, still very positive,'' she said.

"Like anything else, you move on," Mark said. As for life ahead? "Looks pretty good. It's disappointing, but we will still have kids -- some way we will have kids, and I will look at them as if they had my DNA. It's not that traumatic to me, as long as we're still able to raise kids, it doesn't necessarily matter where they came from."

And despite the traumatic turns his life has taken, Mark said he doesn't for a moment regret his decision to enlist in the Marines.

He served, he said, "to make a difference, not just for the United States, our citizens, but over there -- we were making a difference for the people of Afghanistan.

"I wouldn't change it for anything," he said.

For more on the struggles of severely wounded veterans, their families and support systems and the medical personnel dedicated to their healing, check out David Wood's ebook, "Beyond the Battlefield: The War Goes on for the Severely Wounded."