Man produces sperm from testicular tissue frozen as a child in breakthrough trial

A 27-year-old man has produced sperm from testicular tissue frozen as a child in a breakthrough trial, offering hope to boys left infertile by chemotherapy. The tissue was frozen when he was 10 and re-transplanted 16 years later. This is the first time a transplant of cryopreserved prepubertal testicular tissue has restored sperm production in an adult patient.