Azoospermia can be caused by a variety of reasons, the currently known ones include the inability to produce sperm due to testicular spermatogenic dysfunction or a deficiency of certain hormones that affect the spermatogenic process in the testes, or the inability to expel sperm from the body due to blockage of the vas deferens for various reasons, resulting in the absence of sperm present in the semen. In simple terms, azoospermia can be a result of a problem with the production process of sperm or a problem with the transport process of sperm.