Azoospermia is the medical term given to the lack of sperm in a man’s ejaculate and is thought to affect around 1 in 100 men.

There are 2 categories of azoospermia:

  1. Obstructive
  2. Non obstructive

Before explaining each term it is important to understand the journey sperm make from production to ejaculation.

Sperm development begins in the testicles from stem cells where over a period of 9-10 weeks they grow and mature. As they develop, they move out of the testicles into the epididymis where they further mature for another 2 weeks and are then stored ahead of ejaculation.

The final part of the journey as a man ejaculates involves the sperm travelling through a tube called the vas deferens. The vas deferens carry the sperm from the cauda epididymis through to the prostate and ejaculatory duct where they mix with fluid from the seminal vesicle and prostate before leaving the penis via the urethra. The whole process of ejaculation is very fast with sperm travelling at a speed of approximately 5 m/sec.

Obstructive Azoospermia

Obstructive Azoospermia is the medical term to describe an obstruction in the reproductive tract which results in no sperm being ejaculated. This may be a complete or partial blockage however, so few sperm are getting through that a man is then either deemed as Azoospermic or severe oligozoospermic or cryptospermic.

Obstructive Azoospermia is also the term used when there is a congenital absence of the vas deferens.

Obstructive Azoospermia means that the testicles are still working and producing sperm, but due to the obstruction, the sperm cannot be ejaculated.

Of the 2 categories of Azoospermia this is the one that is less of a concern. With obstructive Azoospermia, sperm are still present in the testicles and epididymides which means they can be surgically removed in order to move forward with fertility treatment.

Causes of obstructive Azoospermia

There are a few issues to be aware of that can cause obstructive Azoospermia. They are:

  1. Past or current infections
  2. Trauma to the testicles
  3. Congenital absence of the vasa deferentia
  4. Vasectomy

Infections and trauma

This is one of those areas where a man may recall an issue in the past but will not necessarily associate it with his fertility.

Past urinary tract infections, especially sexually transmitted diseases, are known to cause issues with male fertility. The increase in localised inflammation can cause permanent damage to the urinary tract and parts of the reproductive system. This in turn may lead to a partial or full blockage of the epididymides, vasa deferentia or ejaculatory ducts.

Congenital absence of the vasa deferentia

Often related to Cystic Fibrosis (CF) congenital absence of the vasa deferentia means that sperm produced in the testicles will never be able to be ejaculated.

Cystic Fibrosis is a genetic disorder which affects the movement of salt and water in and out of cells. This condition is known to have an effect on male fertility both in terms of sperm quality but also in the potential for parts of the reproductive tract to either be malformed or missing altogether.

With Azoospermia it is important to discount CF as a potential cause and this needs to be investigated by a qualified medical professional.


A vasectomy is where the vasa deferentia are purposely cut in order to render a man unable to have children. This is often a contraceptive choice made by men which can be reversed should they wish to go on and try for children. However, one must know that the longer a man is vasectomyzed, the poorer his sperm quality will become. It’s also important to note that vasectomy reversal is a lot more complex than a vasectomy with success rates varying and not guaranteed.

The process of further surgery to reconnect the vasa deferentia can cause inflammation leading to scarring and blockages so it is not a guarantee to restore fertility. After about 3 to 5 years, the chances of a refertilization operation being successful is declining drastically and the only chance to obtain sperm would be a surgical sperm aspiration from the epididymis or a testicular sperm extraction.

Non obstructive Azoospermia

Non obstructive Azoospermia tends to be more of a concern when it comes to fertility as it’s usually a sign that the testicles aren’t doing what they should be doing.

In non-obstructive Azoospermia the vasa deferentia, and all the other essential plumbing for that matter, are present and intact. However, the testicles are producing only little or no sperm.

Any man who is diagnosed with non-obstructive Azoospermia will be offered further investigations including a hormone profile and potentially genetic screening to better understand the cause of the Azoospermia. There are many variables when it comes to making this diagnosis and so it’s essential that a man is properly counselled on his diagnosis and treatment options.

On some occasions a man will receive this diagnosis following testing through his GP. If one sample is Azoospermic a further test will be requested, should this also come back with no sperm present it’s important to ensure that a man is referred on to a Urologist / Andrologist so that further investigations can be carried out.

Treatment options

Depending on the cause of the Azoospermia there are several treatment options available, all with the intention of trying to extract sperm from the testicles or epididymis.

  1. Testicular Sperm Aspiration (TESA)
  2. Testicular Sperm Extraction (TESE)
  3. Percutatneous Sperm Aspiration (PESA)
  4. Microsurgical testicular sperm extraction (MicroTESE)

Each method is slightly different and will depend on the cause of the Azoospermia and the likelihood of finding sperm.

If sperm are found, then these can be used for IVF / ICSI treatment.

If no sperm are found through surgical retrieval, then this will sadly be the end of the road for a man’s chance of fathering his own biological child. Sperm donation would be the only way forward at this stage.


Azoospermia is an incredibly tough diagnosis for a man to receive and often comes as a complete shock. Appropriate medical support and counselling are important in order to help a man understand his options and how to deal with the outcomes.

Fertility Network UK offers support online, by phone and through a dedicated HimFertility male fertility support group via Facebook and online meetings.

Counselling can also be found through the British Infertility Counselling Association.

The most important part of dealing with a diagnosis of Azoospermia is finding someone to talk to and getting the support that is needed.