In the United States, an estimated 645,000 men ages 20 to 50 have azoospermia, a condition in which no sperm are present in their ejaculate. Now, scientists are testing a potential treatment: transplanting sperm-forming stem cells into the reproductive system.
"If refined and proven safe, spermatogonial stem cell (SSC) transplantation could be a revolutionary fertility-restoring technique for men who've lost the ability to produce sperm," Dr. Justin Houman, an assistant professor of urology at Cedars-Sinai Medical Center who was not involved in the study, told Live Science in an email.
