UK team transplants cryopreserved testicular tissue in experimental fertility procedure
October 8, 2026 — The University of Edinburgh announced the UK’s first reported transplantation of previously frozen testicular tissue, performed by NHS Lothian as part of a fertility research programme.
The 19-year-old patient had tissue collected and frozen in 2023 before chemotherapy and a bone marrow transplant for a serious blood disorder. Later tests found no sperm in his semen. In August 2026, doctors transplanted some of the preserved tissue back into his body.
The tissue contains spermatogonial stem cells, which researchers hope can support sperm production after transplantation. The patient has recovered well, according to the university. After eight months, a sample of the graft will be examined for evidence of sperm production.
This is an experimental procedure with fertility outcomes still pending. It does not yet demonstrate restored fertility or a pregnancy in this patient. The broader research aims to help boys whose treatment threatens fertility, including those too young to preserve semen.
Source: University of Edinburgh announcement, October 8, 2026. Procedure date: August 2026.