Testicular sperm extraction (TESE) is the process of removing a small portion of tissue from the testicle under local anesthesia and extracting the few viable sperm cells present in that tissue for intracytoplasmic sperm injection (ICSI). The testicular sperm extraction process is recommended to men who cannot produce sperm by ejaculation due to azoospermia, such as that caused by primary testicular failure, congenital absence of the vas deferens or non-reconstructed vasectomy.