Nonobstructive vs. Obstructive Azoospermia

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What is azoospermia?

You may have been told that you have no sperm in your semen.  That is called azoospermia.  There are two broad categories of azoospermia:

  • Obstructive azoospermia means you make sperm but they are blocked somewhere from the testicle to the ejaculatory duct in the urethra.
  • Nonobstructive azoospermia (NOA) means there is not enough sperm production to be seen in the semen.  A testicle may produce very small quantities of sperm that need to be surgically extracted to use for IVF or there may be absolutely no production of sperm.  NOA doesn’t mean there is no chance a man can produce sperm.  There are many reasons, many of these reversible, why a man may have NOA.

Obstructive azoospermia: Causes, Diagnosis and Treatment

Obstructive azoospermia simply indicates a blockage somewhere in the reproductive tract.  Sperm production is normal but the problem lies in the transport of sperm into the ejaculatory duct.  Often, men with obstructive azoospermia will have reduced volumes of semen when the ejaculate.  If the blockage is closer to the testicle such as after a vasectomy, ejaculatory volume will be normal.

Common causes of obstructive azoospermia are listed below.

In order for surgeons to remove a cancerous prostate, they must cut across the vas deferens in the pelvis.  Sperm retrieval is a good option for men to become biologic fathers after prostatectomy.  Surgeons at UCLA Health – The Men’s Clinic are experts at sperm retrieval.

Nonobstructive azoospermia (NOA): Causes, Diagnosis and Treatment

Some common causes of NOA are listed below.

  • Drug-induced NOA.
  • Men on chronic narcotics often have impaired testosterone and sperm production that can be reversed.
  • Men with a history of testosterone replacement, either prescribed or self-administered will essentially always have poor or no sperm production.  This too can often be reversed.
  • Genetic abnormalities
  • History of radiation and chemotherapy
  • Maturation arrest from varicocele

Doctors at The Men’s Clinic at UCLA are world experts on helping men with NOA achieve biologic fatherhood.  Your evaluation will consist of a thorough history of childhood illnesses and surgeries, traumas, previous and current medications, lifestyle risks and many other factors to fully investigate causes and treatments of NOA.  Physical exam is a key component of diagnosing NOA as testicular size is a very good predictor of NOA.  Bloodwork will also be necessary and include genetic tests to determine if there is a chromosomal cause of NOA.  Your doctor may also order imaging tests, commonly ultrasounds of the scrotum and MRI of the pituitary gland looking for reversible causes of NOA.  Often, men’s pituitary hormones, especially FSH, will be high with NOA.

Scheduling an Appointment

Board-certified urologists staff The Men’s Clinic at UCLA and you can be assured you are getting an experienced physician performing your evaluation and procedure in a relaxed and comfortable environment. For more information and to schedule an appointment, please call the UCLA Urology Appointment line at 310-794-7700.