Soldiers give up a lot when they're defending their country. For those who fall victim to snipers and explosives, and who survive, that could mean losing a limb or an organ or their sight. An often unspoken injury is the loss of genitalia. The wars in Iraq and Afghanistan, where roadside bombs are a constant threat, have left more than 1,300 American soldiers mangled in this way. But a team of doctors and scientists at Johns Hopkins Medicine is now ready to help—by performing the first penis transplant in the U.S. (Similar but less extensive procedures have been carried out in China on patients who lost parts of their penises in accidents and in South Africa to repair botched circumcisions).

There isn't just one reason why penis transplants have taken so long to come about in the U.S. Part of it is probably that the transplant is still experimental--the patient in China had to get the procedure reversed after his body rejected the transplant. To many in the medical establishment, that's an unnecessary risk for patients who have already undergone so much physical trauma—a patient's life isn't in danger if he doesn't get a penis, as he would be if he needed a new liver or a kidney.