For young patients facing fertility-threatening treatment, preserving reproductive potential before therapy can be just as important as planning for life after recovery. A pioneering procedure in Edinburgh, UK, has brought this goal a step closer to reality by reintroducing previously frozen testicular tissue into a patient who developed azoospermia following intensive chemotherapy. The 19-year-old patient underwent tissue collection and cryopreservation in 2023 before receiving high-dose chemotherapy and a bone marrow transplant for a serious blood disorder.

Three years later, semen testing revealed no sperm. In August 2026, clinicians transplanted some of his stored testicular tissue back into his body in an attempt to restore sperm production. The procedure, performed by NHS Lothian clinicians with research support from the University of Edinburgh, represents the first transplant of…