Zero sperm count (azoospermia): causes, treatment, and fertility options

• What is azoospermia?
• Types of azoospermia explained
• What causes azoospermia?
• Symptoms of azoospermia
• How is azoospermia diagnosed?
• Can azoospermia be treated?
• Can you get pregnant with zero sperm count?

Azoospermia is the complete absence of sperm in semen. Men with azoospermia are said to have a zero sperm count. Azoospermia is a medical condition that affects approximately 1% of all men and 10% of infertile men. Men with azoospermia can often still produce semen.

The two main types of azoospermia are obstructive azoospermia and non-obstructive azoospermia. They have different causes, results and outcomes.

Obstructive Azoospermia (OA)

The testes produce sperm but a blockage prevents them entering the seminal fluid. 

Cause

The blockage may result from a vasectomy, infection, congenital absence of vas deferens (CBAVD), or issues with the tubes responsible for transporting sperm.

Outcome

Healthy sperm are being produced but cannot make their way to the ejaculate. There is a good chance of successful treatment.

Treatment

Treatments include surgical correction and sperm retrieval for IVF fertility treatment. 

Non-obstructive Azoospermia (NOA)

Testicular dysfunction means sperm production is impaired or abnormal.

Cause

Non-obstructive azoospermia can be caused by genetic conditions (e.g. Klinefelter syndrome), hormone imbalances, testicular injuries, severe infections, or radiation exposure (e.g. from chemotherapy). 

Outcome

The testes are not producing healthy sperm, making treatment more complex. It may still be possible to father a child using your sperm, though the likelihood is lower than with OA.

Treatment

Treatments include hormone therapy and sperm extraction for use in IVF fertility treatments.

Azoospermia is caused by either a blockage that prevents sperm transportation or a sperm production issue in the testes. 

Causes of obstructive azoospermia (blockage)

Obstructive azoospermia occurs when the testes produce viable sperm, but a blockage prevents them from entering the semen and being ejaculated. Obstructive azoospermia can be caused by:

• A vasectomy – a surgical procedure that cuts or seals the vas deferens tubes, preventing sperm from entering the ejaculate. 
• Infection – infections like chlamydia and tuberculosis can cause scars and inflammation that block reproductive tubes. 
• Congenital absence of vas deferens (CBAVD) – the vas deferens carries sperm to the urethra. Some genetic conditions can result in men being born without vas deferens.
• Obstructions in reproductive tubes – a blockage in one of the tubes responsible for storing or transporting sperm. 

Obstructions are found in three main areas in the male genitals:

1. Epididymis – responsible for storing and transporting sperm.
2. Vas deferens – propels sperm during ejaculation via muscle contractions.
3. Ejaculatory duct – combines sperm with seminal fluid.

Causes of non-obstructive azoospermia (production issue)

Non-obstructive azoospermia occurs when the testes produce no or very little sperm. It is an issue with the testicles rather than the tubes responsible for transporting sperm. It can be caused by:

• Genetic conditions – some genetic conditions, such as Klinefelter syndrome and chromosome abnormalities, impact sperm production and result in azoospermia.
• Hormone imbalances – low testosterone levels and issues with the pituitary gland can disrupt hormones and reduce sperm production.
• Testicular injuries – reduced blood flow due to testicular trauma can damage sperm producing cells. 
• Severe infections – infections that damage the testicular tissue may impact sperm production.
• Radiation exposure – radiation can damage sperm-producing cells in the testes. Non-obstructive azoospermia can be a temporary or permanent side-effect of chemotherapy.

Most people with azoospermia have no noticeable symptoms. You may only become aware of the condition if you struggle to conceive and see a fertility specialist. Others may experience one or more of the following symptoms:

• Sexual dysfunction – issues with getting or maintaining an erection and a low sex drive.
• Testicular abnormalities – changes in size or feel of testicles. Small or swollen testicles can indicate an issue, as can firm, tender or particularly uncomfortable testicles. See a healthcare professional if you notice any changes in your testicles.
• Hormonal indicators – signs associated with hormonal imbalance include a noticeable reduction in facial or body hair and larger, tender or swollen breasts.
• Low semen volume – ejaculating small amounts of semen or “dry ejaculation” can indicate azoospermia.

Azoospermia diagnosis begins with semen analysis. Semen analysis is a male fertility test that evaluates several sperm health indicators, including sperm count, motility, morphology and semen volume. The semen analysis will tell you your sperm count and indicate whether you have azoospermia. Most fertility specialists will request two samples gathered at different times to account for natural variability and outliers. 

After the initial sperm analysis, your fertility specialist will try to determine the cause of your azoospermia and whether you have obstructive or non-obstructive azoospermia. They may use the following diagnostic tools and methods.

• Physical examination – the healthcare professional may examine your testicles for signs of swelling, firmness or tenderness. 
• Hormone testing – a blood test to measure testosterone, LH (luteinising hormone) and FSH (follicle-stimulating hormone) levels, and check for imbalances.
• Genetic screening – a saliva or blood test will be taken, and the DNA analysed to check whether you have any genetic conditions associated with azoospermia.
• Genital tract imaging – ultrasound, MRI or CT scans can be used to identify blockages or the absence of the vas deferens.
• Testicular biopsy – in rare cases, a testicular biopsy may be used to check whether the testes are capable of producing sperm.

Successful azoospermia treatment depends on the type of azoospermia you have and the root causes. Obstructive azoospermia is often easier to treat than non-obstructive azoospermia, as blockages tend to be simpler to repair than sperm production issues. However, advanced medical, hormonal and surgical treatments and assisted reproductive technologies (ARTs) enable many men facing fertility challenges to have children. This means it is possible to treat even severe cases of non-obstructive azoospermia.

Hormonal and medical treatments

Hormone therapy is used to address the hormone imbalances that can cause azoospermia. Abnormalities in the pituitary gland or hypothalamus may disrupt hormone production, resulting in low testosterone levels and issues producing sperm. Hormone replacement therapy is a common treatment in these cases. 

Surgical treatment options

Surgical treatments are used in cases of obstructive azoospermia to remove blockages and open up the tubes responsible for transporting sperm. Surgical treatments vary depending on where the obstruction is and why it occurred. Common surgical azoospermia treatments include:

• Varicocele repair – a microsurgical procedure used to treat enlarged veins by tying them off. This can help the testicles return to normal sperm production.
• Vasectomy reversal – a microsurgical procedure that reconnects the vas deferens tubes, returning sperm to the semen. 
• Microsurgery – a small incision is made in the scrotum and any blockages cleared using magnification technology and specialist tools. It is typically used for epididymis and vas deferens obstructions.
• Endoscopic surgery – a thin, flexible scope with an integrated camera is threaded through the urethra and used to clear the blockage without the need for an incision. It is typically used for ejaculatory duct obstructions.

Sperm retrieval and assisted reproduction

Sperm can sometimes be retrieved directly from the testicles and used together with assisted reproductive technologies to conceive. This may enable men with azoospermia to have children using their own sperm. The key procedures connected with sperm retrieval and ART include:

• MicroTESE – a microsurgical testicular sperm extraction is a  procedure used to extract sperm from the testicles. An incision is made in the scrotum, the testicle is opened up, and the surgeon removes tubules likely to contain healthy sperm. It is typically used to treat men with severe non-obstructive azoospermia.
• IVF – In Vitro Fertilisation is a fertility treatment in which mature eggs are taken from the female partner’s ovaries and fertilised in the lab using the male partner’s sperm. The embryo is then returned to the uterus to develop.
• ICSI – Intracytoplasmic Sperm Injection is a specialised form of IVF in which fertility specialists isolate a single healthy sperm from the male’s semen and inject it directly into the egg in lab conditions. If a man undergoes MicroTESE to extract sperm, ICSI will be the treatment used to fertilise the egg.

Pregnancy is possible even when a man has zero sperm count, because treatment or sperm retrieval can enable fertilisation in specific cases. It depends on the nature of the condition, the treatment options available, and whether treatment is successful.

Men who are trying to conceive will usually progress along the following treatment pathway, moving on to the next stage if treatment is unsuccessful or unviable:

1. Surgical or hormonal treatment to improve sperm count and conceive via sexual intercourse.
2. MicroTESE sperm retrieval and ICSI treatment.
3. Fertility treatment using donor sperm.

Fertility treatments using donor sperm enable men facing severe fertility challenges to become fathers. While you may have questions about using a donor, it’s a path that many men have taken, and there is a lot of support available for couples considering it. The most important thing is to know that, no matter what, you will always be your child’s father. It’s a parent’s love, support and care that makes a family, not biology. 

Today, donor search tools can also help you match with a donor who physically resembles you or that shares certain personality traits, and detailed profiles give you a deeper insight into the donor you’re choosing.

What is the best treatment for dead sperm?

Dead sperm in the semen (necrozoospermia) is usually treated with MicroTESE sperm retrieval and ICSI, as this enables healthcare professionals to extract living sperm from the testicles. Necrozoospermia is distinct from azoospermia, and the two conditions should not be confused.

Why am I “shooting blanks”?

Azoospermia is sometimes referred to colloquially as “shooting blanks” and occurs because of a blockage that prevents sperm transportation or a sperm production issue in the testes.

Can a man recover from a zero sperm count?

Many men do recover from a zero sperm count, but recovery depends on the type, severity and cause of your azoospermia. Obstructive azoospermia tends to be the easiest to treat, though there are several treatment options for men with non-obstructive azoospermia, too. If treatment is not viable, fertility treatments using donor sperm are an option.