In a historic medical first, a young man has received a sperm-forming stem cell transplant — a pioneering procedure that could open new doors for some men who face infertility after cancer treatment. The patient, now in his early 20s, had become infertile after undergoing chemotherapy in childhood to treat a bone malignancy. As a side effect of his treatment, he developed “azoospermia”, a term that means no sperm is present in the semen.
Now, there’s new hope. Doctors used the man’s own stem cells — preserved before his cancer treatment — and reintroduced them into his testicles. These special cells, known as spermatogonial stem cells, have the potential to mature and eventually produce sperm. If successful, the procedure could essentially give the patient a “second chance” at both puberty and fertility.
While this is the first time such a transplant has been performed in a human, the technique has already allowed mice and monkeys to father offspring. So far, no sperm has been detected in the man’s semen, but hormone levels are normal and the report states his reproductive tissues are unharmed — promising early signs.
This breakthrough could be life-changing for men who lost fertility due to cancer treatments, and potentially in the future also for men with genetic conditions, or testicular failure. As Dr. Justin Houman of Cedars-Sinai notes, if this technique proves safe and effective, it could revolutionize fertility restoration.
Though challenges remain — including the risk of insufficient stem cells or potential complications — the future looks hopeful. This pioneering step marks a promising new frontier in the treatment of male infertility.
This article brings attention to a subset of patients with “non-obstructive azoospermia” or NOA which is a condition I see on a regular basis in my office. As mentioned, there is no sperm in the ejaculate specifically due to the presence of very few or no sperm make cells (spermatogonia) in the testes. It is encouraging to see some potential progress in this case and more hope into the future for my patients who have this condition.
The source for this blog includes media articles and the manuscript:
Ultrasound-Guided Rete Testis Approach to Sperm Aspiration and Spermatogonial Stem Cell Transplantation in Patients with Azoospermia
by Amanda Colvin Zielen et al
doi: https://doi.org/10.1101/2025.03.25.25324518
