TESA, PESA, TESE and Micro-TESE for Azoospermia Compared

Surgical Sperm Retrieval Compared: TESA, PESA, TESE and Micro-TESE for Azoospermia

There's a particular silence that follows a man being told there's no sperm in his sample. Not low. None. For most men, the word that comes next, somewhere in their own head, is "never." No biological children. Donor sperm, adoption, or nothing.

That conclusion is almost always wrong, and it helps to know why before the panic sets in. A zero sperm count in the ejaculate doesn't mean there's no sperm anywhere in the body. It means none is reaching the semen. In many men with azoospermia, sperm is still being produced or is trapped further upstream in the reproductive tract. It can often be retrieved directly with a minor surgical procedure and then used to fertilise an egg through IVF with ICSI.

The real question is rarely whether sperm exists. It's how to retrieve it, and which of the four common surgical sperm retrieval procedures—TESA, PESA, TESE, or Micro-TESE—is most appropriate.

This guide explains the differences between these procedures for men who have recently been diagnosed with azoospermia and couples trying to understand their fertility treatment options.

Why a Zero Sperm Count Doesn't Mean There Is No Sperm

Azoospermia simply means there are no sperm present in the ejaculate. It affects approximately one in every hundred men and accounts for around ten percent of male infertility cases.

Fortunately, modern fertility treatment doesn't require millions of sperm to achieve pregnancy. During Intracytoplasmic Sperm Injection (ICSI), a single healthy sperm is injected directly into a mature egg. As a result, retrieving only a small number of viable sperm from the testicle is often enough to fertilise an entire batch of eggs.

The goal is not to produce a normal semen sample. The goal is simply to retrieve enough healthy sperm to achieve fertilisation.

The Most Important Question: Blockage or Production Problem?

Before choosing any sperm retrieval procedure, one question must first be answered:

Is azoospermia caused by a blockage, or is the testicle producing very little or no sperm?

Two men can both have a semen analysis showing zero sperm, yet have completely different underlying conditions.

• Obstructive Azoospermia: The testes produce healthy sperm, but a blockage prevents sperm from reaching the semen. This may result from a previous vasectomy, infection, or a congenital absence of the vas deferens.
• Non-Obstructive Azoospermia: The problem lies within the testes themselves, where sperm production is severely reduced or occurs only in small isolated areas.

This distinction determines which surgical procedure offers the greatest chance of finding sperm. Hormone tests, physical examination, ultrasound, and sometimes genetic testing help determine the underlying cause before treatment begins.

Approximately 60–70% of azoospermia cases are classified as non-obstructive.

When the Cause Is a Blockage: PESA and TESA

If sperm production is normal and only a blockage prevents sperm from reaching the semen, retrieval is usually straightforward.

PESA (Percutaneous Epididymal Sperm Aspiration)

PESA involves inserting a fine needle through the skin into the epididymis—the coiled tube behind the testicle where sperm is stored. The sperm is gently aspirated through the needle.

The procedure requires only local anaesthesia, leaves no incision, and usually takes only a few minutes.

TESA (Testicular Sperm Aspiration)

TESA is a similar minimally invasive procedure, but instead of retrieving sperm from the epididymis, a fine needle is inserted directly into the testicle to collect a small amount of tissue containing sperm.

TESA is also performed under local anaesthesia with minimal recovery time.

For men with obstructive azoospermia, both PESA and TESA achieve sperm retrieval success rates approaching 100% because sperm production remains normal.

When the Problem Is Sperm Production: TESE and Micro-TESE

Non-obstructive azoospermia presents a greater challenge because sperm production itself is impaired.

TESE (Testicular Sperm Extraction)

TESE involves making a small incision in the testicle and removing one or more pieces of testicular tissue. Fertility laboratory specialists then examine the tissue under a microscope to search for any sperm.

The procedure is generally performed under sedation or general anaesthesia.

Because sperm production may occur only in isolated areas, conventional TESE sometimes retrieves tissue that contains no sperm.

Micro-TESE (Microsurgical Testicular Sperm Extraction)

Micro-TESE is a more advanced surgical technique performed using an operating microscope.

Instead of removing tissue blindly, the surgeon carefully examines the seminiferous tubules and selectively removes those that appear larger and healthier, as these are more likely to contain sperm.

This targeted approach improves the chances of sperm retrieval while preserving healthy testicular tissue.

Why Micro-TESE Has Become the Gold Standard

Although Micro-TESE is the most sophisticated sperm retrieval procedure, it often removes the least amount of healthy tissue.

The operating microscope allows the surgeon to identify the tubules most likely to contain sperm rather than taking random tissue samples.

• Higher sperm retrieval rates.
• Less removal of healthy tissue.
• Better preservation of blood supply.
• Reduced damage to overall testicular function.

For men with non-obstructive azoospermia, these advantages have made Micro-TESE the preferred surgical approach worldwide.

What Are the Success Rates?

Success rates depend largely on whether azoospermia is obstructive or non-obstructive.

• Obstructive Azoospermia: PESA and TESA achieve sperm retrieval success rates in the high 90% range, often approaching 100%.
• Non-Obstructive Azoospermia: Conventional TESE retrieves sperm in approximately one-third of patients.
• Micro-TESE: Retrieval rates increase to around 50%, with some published studies reporting success approaching 60% depending on the underlying diagnosis.

The exact chances vary according to hormone levels, testicular size, and the underlying cause of infertility.

Importantly, only a small number of healthy sperm are needed for IVF with ICSI. Even a handful of sperm can be enough to fertilise multiple eggs.

What No Test Can Guarantee

One difficult reality remains for men with non-obstructive azoospermia.

No blood test, ultrasound scan, hormone level, or physical examination can guarantee that sperm will be found before surgery. The only definitive answer comes during the retrieval procedure itself.

Even men with encouraging test results may unfortunately have no retrievable sperm.

This uncertainty is why choosing the correct procedure is so important. More invasive surgery is not automatically better. Men with obstructive azoospermia generally do not require Micro-TESE because simpler needle aspiration techniques provide excellent results.

The key is selecting the surgical approach that matches the underlying cause of azoospermia.

Conclusion

A diagnosis of azoospermia does not automatically mean biological fatherhood is impossible.

For many men, sperm are still present within the reproductive system and can be successfully retrieved using modern surgical techniques such as PESA, TESA, TESE, or Micro-TESE.

The most important step is determining why sperm are absent from the semen. Once the cause has been identified, your fertility specialist can recommend the most appropriate retrieval procedure and the best path forward.

If you've recently been diagnosed with azoospermia and want to explore your treatment options, book a consultation with MMC IVF today and learn which surgical sperm retrieval technique may be right for you.