Testicular biopsy is a minor surgical procedure that involves the removal of a small sample of testicular tissue. It may be performed to find the cause of male infertility or to confirm an obstruction of the male reproductive tract. It may also be done if there is a suspicious lump, to determine if it's cancerous, although that is not part of a male fertility work-up.
Because of the risk of damage to the testicles, it’s only performed when other testing is inconclusive.
Testicular biopsy may also be performed as part of testicular sperm extraction (TESE), which is a method of extracting sperm directly from the testes for use in IVF treatment or ICSI. This may be used in cases of azoospermia, when sperm does not get into the semen, but is still being produced in the testes.