Surgeons in the United Kingdom have performed the country’s first testicular tissue transplant on a 19-year-old patient, marking a significant advance in fertility preservation for males affected by chemotherapy. The procedure was carried out in August by a medical team at NHS Lothian in Edinburgh and offers new hope for boys and young men facing infertility due to cancer treatment.

The patient, who requested anonymity, had tissue removed and frozen three years earlier before undergoing chemotherapy for a serious blood disorder. Chemotherapy can irreversibly damage the cells responsible for sperm production, often leaving patients infertile. Tests conducted after his treatment found no sperm in his semen. The transplant aims to restore the ability to produce sperm by reintroducing previously frozen testicular tissue containing spermatogonial stem cells, which develop into sperm after puberty.

“This is a big step towards helping boys facing treatments that damage their fertility to have children of their own,” said Rod Mitchell, professor of developmental endocrinology at the University of Edinburgh and a consultant paediatric endocrinologist at NHS Lothian. Mitchell highlighted that the transplant follows a decade of research into freezing and storing testicular tissue from pre-pubescent boys before chemotherapy begins—a group for whom traditional fertility preservation methods such as sperm freezing are not feasible.

Medical director at NHS Lothian Tracey Gillies described the operation as a “landmark procedure,” emphasizing its potential impact on care for children whose fertility may be compromised by life-saving treatments. The 19-year-old patient expressed gratitude for the opportunity, acknowledging that the transplant has given him hope for fathering biological children despite previous concerns about his fertility.

While the success of the procedure in restoring sperm production remains to be determined, doctors expect to know within months whether viable sperm has been generated. This UK case is reportedly only the second such transplant performed globally. Previous reports from the United States have shown similar approaches yielding positive outcomes years after tissue was frozen and retransplanted.

The operation was conducted with support from the charity Children with Cancer UK and builds on a growing body of research from the University of Edinburgh. Currently, more than 1,200 patients in the UK and approximately 3,100 worldwide have had testicular tissue preserved for potential future use.

The transplant represents a potential breakthrough in addressing fertility challenges faced by pre-pubescent boys and adolescents undergoing chemotherapy, expanding options beyond current methods that largely rely on semen storage, which is not possible before puberty. Researchers and clinicians hope the procedure will pave the way for improved fertility preservation strategies in pediatric oncology.