- Obstructive Azoospermia (OA)
Azoospermia is the medical condition of a man whose semen contains no sperm. This is different from Aspermia – wherein there is neither sperm nor any semen. Causes of Azoospermia include a blockage along the reproductive tract, in which case it is known as obstructive azoospermia.
- Nonobstructive Azoospermia (NOA)
Nonobstructive azoospermia is when the semen contains no sperm, and may be caused by hormonal problems, ejaculation problems or issues with testicular structure or function.