Transplanted testicles will always make the donor’s sperm

A veteran of the US Armed Forces has a new penis and scrotum after the most extensive penis transplant yet, Johns Hopkins Hospital announced this week. Not included in the transplant? Testicles — because the testicles would continue to make the donor’s sperm in the transplant recipient’s body.

The patient, who asked Johns Hopkins not to reveal his name, suffered a devastating injury to his penis, testicles, part of his lower abdomen, and his legs in Afghanistan when an improvised explosive device blew up, The New York Times reports. A team of 11 surgeonsreplaced the injured flesh of his genitals and lower abdomen with tissue from a deceased donor during a 14-hour surgery at the end of March, and the patient is recovering well, according to a news briefing on Monday. But the transplant didn’t include testicles — something that the Johns Hopkins team decided early on was off the table, says Damon Cooney, a plastic and reconstructive surgery professor at the Johns Hopkins University School of Medicine.

While Cooney couldn’t discuss the particulars of...