Japanese researchers have grown sperm in the laboratory for the first time, reports Nature. If the breakthrough with mice transfers to humans, it could open up IVF treatments for infertile men, notes the Guardian. Scientists created the sperm from the testicular tissue of mice and successfully produced a dozen baby mice with it.
The tissue worked even after being frozen, suggesting that men—or even boys too young to produce sperm—could freeze tissue for later use if they were undergoing chemotherapy or other treatments that can cause infertility. "The report is quite exciting because it represents the fulfillment of a goal held by many reproductive biologists over many years," says an expert in the field at the Jackson Laboratory in Bar Harbor, Maine. (More sperm stories.)