Non-obstructive azoospermia refers to no sperm in the semen because of abnormal sperm production. Sperm production problems can result from hormonal problems, testicular failure, or varicocele, or varicose veins in the testicles.
Problems with the ductal system or issues with ejaculation can cause obstructive azoospermia. The ducts can be missing, or blocked, or the man could have an absence of the vas deferens, the tube that transports sperm for ejaculation...
Azoospermia is one condition that can cause male infertility. With azoospermia, a man produces no sperm, or very little sperm in his ejaculate, giving him a zero sperm count. Azoospermia can result from a problem with sperm production or sperm delivery. While this may seem like it would prohibit a man from fathering a child, there are treatment options that may help a man with azoospermia deliver sperm correctly or produce more sperm.
Eisenberg says the finding of the study should be a wake-up call to men, most of whom don’t have a primary care physician until they are older. His recommendation is that men see a doctor annually for a physical exam, and that men with azoospermia have regular cancer screenings.