Azoospermia is a specific disorder that affects fertility. Generally, there are two types of azoospermia, namely obstructive azoospermia and non-obstructive azoospermia. Obstructive azoospermia is a condition in which the testes have a spermatogenic function, but there are problems with the sperm drainage ducts and the sperm cannot exit the reproductive tract to produce their own offspring. 1. What are the common sites of obstruction in obstructive azoospermia? Common obstruction sites include intra-testicular obstruction, epididymal obstruction, vas deferens obstruction, and ejaculatory duct obstruction. 2. How can patients with obstructive azoospermia choose the appropriate fertility method? (1) For intra-testicular obstruction, both surgical treatment and medication are not effective. Sperm need to be retrieved through surgery and IVF should be chosen to produce their own offspring. (2) Obstruction sites that can be recanalized include epididymal obstruction, vas deferens obstruction and ejaculatory duct obstruction. If natural pregnancy is required, microscopic epididymal vasovasostomy (for epididymal obstruction), vasovasostomy (for vasovaginal obstruction), and ejaculatory ductotomy (for ejaculatory duct obstruction) can be attempted, and if successful, there is a chance of natural pregnancy. It is recommended to keep the sperm obtained during the surgical exploration during recanalization as a backup. This is to prevent failure of recanalization or to reduce the number of surgical sperm retrieval for IVF treatment if recanalization is not possible. (3) If you do not want to opt for recanalization surgery, you can obtain a small amount of sperm through microsurgery, etc. and use the second generation IVF technology to have your own offspring.