NHS Lothian carries out first UK testicular tissue transplant in 19-year-old

NHS Lothian doctors in Edinburgh have carried out the UK's first reported testicular tissue transplant, returning frozen tissue to a 19-year-old in August 2026 after chemotherapy left him with no sperm in his semen. The operation, reported on 8 October, offers a possible route to preserving fertility for boys treated before puberty, but doctors do not yet know whether the graft will produce viable sperm.

The patient, who asked to remain anonymous, had tissue removed and frozen in 2023 before treatment for a serious blood disorder. According to the University of Edinburgh, he subsequently underwent a bone marrow transplant involving high-dose chemotherapy. Tests three years after treatment found no sperm in his semen. He has recovered well from the transplant procedure and will be monitored, the university said.

Why doctors stored testicular tissue before chemotherapy

Chemotherapy can permanently damage the cells needed to make sperm. Older teenagers and adults may be able to freeze semen before treatment, but boys who have not reached puberty do not yet produce sperm to store. For them, freezing testicular tissue has been a potential option for preserving the cells that could make sperm later in life; returning that tissue has remained experimental.

The stored tissue contains spermatogonial stem cells, which are responsible for sperm production from puberty onwards. Doctors hope that placing some of the young man's tissue back in his body will allow those cells to produce sperm. The operation establishes that the transplant has taken place; it does not establish that sperm production has resumed or that the patient will be able to have biological children.

How the Edinburgh transplant will be assessed

The University of Edinburgh said doctors will monitor the patient and remove some transplanted tissue for examination after eight months to determine whether it has produced sperm. The Guardian reported that doctors expect to learn within months whether viable sperm are produced. Neither source reports a successful fertility outcome for this patient.

The procedure was performed by NHS Lothian medics after more than a decade of research at the University of Edinburgh. Children with Cancer UK funded the tissue preservation programme and later supported the transplantation study, according to the university's announcement. The university says more than 1,200 patients in the UK and 3,100 worldwide have had testicular tissue stored for possible future use. Those figures count stored tissue, not successful transplants or restored fertility.

What the earlier Belgian case showed

The Edinburgh operation is described by the Guardian and the university as the second reported procedure of its kind worldwide. In Belgium, researchers transplanted tissue that had been frozen when a patient was 10, before chemotherapy for sickle cell disease. The Guardian reported in May that mature sperm were recovered from grafts after a year. That case provides a precedent for sperm production from frozen tissue, but it does not establish the outcome of the UK operation.

In the Belgian case, tissue fragments were not connected to the sperm duct, so researchers did not expect sperm to enter the patient's semen naturally. The Guardian reported that it remained unknown whether the sperm recovered from the grafts could fertilise an egg. Production of sperm and the ability to have a biological child are therefore separate questions in assessing this approach.

For families facing treatment that may damage a child's future fertility, the UK procedure is a step toward testing whether stored tissue can be used years later. Its immediate significance is the attempt to restore sperm production in a patient whose tissue was frozen before treatment. The answer will depend on follow-up examination and monitoring, rather than on the operation alone.