The correct sperm retrieval procedure is chosen from the cause of azoospermia, not from which procedure sounds easiest. PESA removes sperm from the epididymis and is mainly used when sperm production is normal but blocked. TESA samples the testis with a needle and is also useful in obstructive azoospermia. Micro-TESE is an open microsurgical search for non-obstructive azoospermia, where sperm production may survive only in small scattered areas. A TESA being simpler does not make it the right procedure for NOA; using a low-yield procedure first can add another intervention without solving the actual problem.

Quick comparison: PESA vs TESA vs micro-TESE

What is PESA?

Percutaneous epididymal sperm aspiration (PESA) passes a fine needle into the epididymis to aspirate fluid containing sperm. It is usually performed under local anaesthesia or short anaesthesia depending on the setting. Because sperm production is generally normal in obstructive azoospermia, the epididymis can contain large numbers of mature sperm.

PESA is most useful when

• There is obstructive azoospermia, such as after vasectomy or epididymal obstruction.
• The vas deferens is absent or sperm cannot reach the ejaculate because of a known obstruction.
• The plan is to use retrieved sperm with ICSI.

PESA is minimally invasive, but it is a blind needle procedure. If adequate sperm are not obtained, the surgeon may proceed to another epididymal or testicular retrieval depending on the plan made beforehand.

What is TESA?

Testicular sperm aspiration (TESA) uses a needle to obtain small cores or aspirates of testicular tissue. An embryologist examines the material for sperm. In obstructive azoospermia, sperm production is usually distributed throughout the testis, so TESA can work well. A meta-analysis comparing PESA and TESA for obstructive azoospermia found similar pregnancy and miscarriage outcomes with ICSI.

TESA is most useful when

• Obstructive azoospermia is present and testicular retrieval is preferred.
• PESA does not yield adequate sperm or epididymal access is not suitable.
• A prior vasectomy or another obstruction prevents sperm from reaching the semen.

Why TESA is not the preferred procedure for non-obstructive azoospermia

In NOA, sperm production can be extremely patchy. A needle samples only small random areas and may miss rare foci of spermatogenesis. EAU guidance advises against testicular sperm aspiration in NOA, and AUA/ASRM recommends micro-TESE for men with NOA undergoing sperm retrieval.

What is micro-TESE?

Microdissection testicular sperm extraction (micro-TESE) is performed through a small scrotal incision. The testis is opened and examined under an operating microscope. The surgeon selectively samples larger or more opaque seminiferous tubules that may be more likely to contain sperm, while trying to remove as little tissue as necessary. The embryology team searches the tissue carefully for usable sperm.

Micro-TESE is most useful when

• Non-obstructive azoospermia has been confirmed.
• Sperm production is severely impaired because of primary testicular failure, some genetic conditions, previous undescended testis or gonadotoxic injury.
• A prior non-microsurgical testicular retrieval has failed and salvage micro-TESE is being considered.

Does micro-TESE guarantee sperm?

No. It improves the chance of finding focal sperm production in NOA compared with random aspiration, but it cannot create sperm where none are being produced. Retrieval rates in published NOA series are often around 40-50% overall, but individual probability depends on the diagnosis. FSH and testicular size alone are not reliable enough to promise success or deny surgery.

What about MESA and conventional TESE?

Microsurgical epididymal sperm aspiration (MESA) is an open microsurgical epididymal retrieval that can obtain a larger quantity of sperm in obstructive azoospermia and may be useful when cryopreserving multiple samples is important. Conventional TESE removes small pieces of testicular tissue without the extensive microscopic search used in micro-TESE. The exact choice depends on the cause of azoospermia, local expertise, previous surgery and IVF laboratory requirements.

Fresh sperm or frozen sperm?

Both fresh and cryopreserved surgically retrieved sperm can be used for ICSI. In obstructive azoospermia, retrieval and freezing in advance is often practical because sperm numbers are usually adequate. In NOA, some teams coordinate micro-TESE with egg retrieval because only a small number of sperm may be found and not every sample survives freezing and thawing equally well.

Anaesthesia, recovery and risks

PESA and TESA are usually shorter needle procedures and may be done with local anaesthesia, sedation or short general anaesthesia. Micro-TESE is an operating-room microsurgical procedure and usually requires anaesthesia. Temporary pain, swelling and bruising can occur after any retrieval. Haematoma, infection and testicular injury are uncommon but possible. Micro-TESE can also cause a temporary fall in testosterone in some men, which is why follow-up is important.

How a urologist decides which procedure you need

• Is the azoospermia obstructive or non-obstructive?
• Are the testes normal-sized, and what are FSH/LH/testosterone levels?
• Are the vas deferens present and is there a history of vasectomy, infection or reconstruction?
• What genetic testing is required before retrieval?
• Has a previous retrieval been attempted, and what did it show?
• Does the IVF laboratory need fresh sperm, frozen sperm or a larger sample for multiple cycles?

How the decision should actually be made

Start with the diagnosis: obstruction versus impaired production. Then consider previous surgery, hormone/genetic findings, whether fresh or frozen sperm are needed, and how the retrieval will be coordinated with the IVF laboratory. The goal is not the smallest procedure; it is the least invasive procedure that still has a high chance of finding usable sperm.

• Do not undergo sperm retrieval before confirming azoospermia and completing the necessary genetic evaluation.
• Do not assume PESA or TESA is always better than reconstruction in a young couple with a correctable obstruction.
• Do not start testosterone before or after retrieval while actively pursuing fertility unless a reproductive specialist has specifically planned it.

What to bring for consultation

• Two semen analyses confirming azoospermia if available.
• FSH, LH and morning testosterone.
• Karyotype, Y-chromosome microdeletion and CFTR testing when indicated.
• Previous vasectomy, hernia, scrotal or fertility-surgery records.
• Previous PESA/TESA/TESE/micro-TESE and IVF laboratory reports.

FAQs

Related reading

• No Sperm in Semen: Can You Still Become a Father?
• What If Micro-TESE Does Not Find Sperm?
• Genetic Testing in Male Infertility
• Urologist in Latur

References

• American Urological Association/American Society for Reproductive Medicine. Diagnosis and Treatment of Infertility in Men: AUA/ASRM Guideline (2020; Amended 2024) https://www.auanet.org/guidelines-and-quality/guidelines/male-infertility
• European Association of Urology. EAU Guidelines on Sexual and Reproductive Health: Male Infertility. 2026 https://uroweb.org/guidelines/sexual-and-reproductive-health/chapter/male-infertility
• Shih KW, Shen PY, Wu CC, Kang YN. Testicular versus percutaneous epididymal sperm aspiration for patients with obstructive azoospermia: a systematic review and meta-analysis. Transl Androl Urol. 2019;8(6):631-640. doi:10.21037/tau.2019.11.20.
• Schlegel PN. Testicular sperm extraction: microdissection improves sperm yield with minimal tissue excision. Hum Reprod. 1999;14(1):131-135.