Micro-TESE (microdissection testicular sperm extraction) is a microscope-guided operation used mainly to look for sperm in men with non-obstructive azoospermia. The surgeon opens the testis and examines seminiferous tubules under high magnification, selectively sampling larger or more promising tubules so the embryology team can search them for rare sperm. The goal is to improve sperm retrieval while removing less unnecessary testicular tissue than multiple blind biopsies. Current EAU and ASRM guidance favour micro-TESE when surgical sperm retrieval is planned for NOA.

Who may need micro-TESE?

• Confirmed non-obstructive azoospermia after appropriate semen pellet examination.
• Klinefelter syndrome with azoospermia when biological paternity is desired.
• Selected men with spermatogenic failure after chemotherapy/radiotherapy.
• NOA after evaluation of genetic and endocrine causes when sperm retrieval remains reasonable.
• Some men after failed conventional retrieval, depending on the diagnosis and previous surgical details.

Who should not undergo micro-TESE?

Micro-TESE is not appropriate merely because sperm count is low. It is also not useful when a complete AZFa or AZFb Y-chromosome deletion has established an essentially zero chance of retrieval. Men with obstructive azoospermia usually have simpler and more predictable retrieval options such as PESA, TESA, MESA or TESE.

Evaluation before surgery

• At least two appropriate semen assessments confirming azoospermia, including pellet search.
• Physical examination and testicular volume assessment.
• FSH, LH and morning testosterone.
• Karyotype and Y-chromosome microdeletion testing when indicated.
• Review of previous biopsy/TESE/micro-TESE reports.
• Coordination with the IVF laboratory and the female partner’s treatment plan.

How micro-TESE is performed

The procedure is usually done under general or regional anaesthesia, sometimes with local techniques depending on centre practice. A small scrotal incision exposes the testis. The tunica albuginea is opened, and an operating microscope—often around 20–25× magnification—is used to inspect seminiferous tubules. Tubules that appear larger or more opaque may be preferentially sampled because they are more likely to contain active spermatogenesis.

Small tissue samples are passed repeatedly to the embryology laboratory for mechanical processing and microscopic sperm search. The search continues in a systematic manner until usable sperm are found or the surgeon judges that further dissection would add tissue injury without reasonable benefit. The testicular coverings and scrotal incision are then closed.

One testis or both testes?

Many surgeons begin on the testis judged more favourable. If no sperm are found, the opposite testis may be explored depending on the diagnosis, intraoperative findings and preoperative counselling. Bilateral exploration is not automatic in every case.

How successful is micro-TESE?

Success varies greatly with the underlying biology and how studies select patients. EAU reviews report overall sperm retrieval around the mid-40% range in pooled NOA literature, but this number should not be applied as a guaranteed personal probability. Klinefelter syndrome, prior cryptorchidism, histology and specific genetic findings can shift the chance. Complete AZFa/AZFb deletions are a clear poor-prognosis exception.

Fresh versus frozen sperm

If enough sperm are retrieved and survive freezing, cryopreservation allows the male procedure to be separated from egg retrieval. Some centres synchronise micro-TESE with oocyte retrieval in NOA because only very few sperm may be found or freeze-thaw survival is uncertain. Both strategies are used; the best plan depends on the couple and laboratory.

Hospital stay and early recovery

Micro-TESE is commonly a short-stay or day-care procedure, though hospital practice varies. Mild-to-moderate scrotal soreness, bruising and swelling are expected. Supportive underwear, wound care and avoiding strenuous exercise or heavy lifting are usually advised during the early recovery period. Desk work may resume sooner than heavy physical work.

Risks and complications

• Scrotal haematoma or bleeding.
• Wound infection.
• Pain and swelling.
• Testicular tissue loss/scarring, although microscopic selection aims to limit unnecessary sampling.
• Temporary fall in testosterone; men with NOA already have a higher baseline risk of hypogonadism and may need long-term endocrine follow-up.
• Failure to retrieve sperm despite technically adequate surgery.

What happens if sperm are found?

The embryology team assesses viability and quantity. Sperm are usually used for ICSI because the numbers are too low for conventional IVF. Extra usable sperm may be frozen. The couple should understand that sperm retrieval is only the male part of the process; fertilisation, embryo development, implantation and live birth depend on both partners and the IVF cycle.

What happens if no sperm are found?

The operative and embryology reports should be reviewed together with genetics and prior histology. A second micro-TESE is not automatically useful; the decision depends on whether the first operation was comprehensive, whether the diagnosis has changed and whether there is a realistic biological reason for another attempt. Donor sperm and other family-building pathways should be discussed respectfully when appropriate.

Before micro-TESE

The diagnosis of non-obstructive azoospermia should be established before surgery. This usually includes repeat semen examination with pellet search, careful testicular examination, FSH/testosterone assessment and the genetic tests indicated by the clinical picture. Complete AZFa or AZFb Y-chromosome deletions predict essentially no useful retrieval and are important to identify before exposing a man to surgery.

Laboratory coordination matters

Micro-TESE is a surgical-embryology procedure, not only an operation. Retrieved tubules must be processed immediately by an experienced embryology team to look for rare viable sperm and to freeze usable sperm when possible. The plan for fresh versus frozen sperm and timing of the female partner’s oocyte retrieval should be agreed in advance.

What micro-TESE can and cannot promise

Micro-TESE improves the ability to search selectively for enlarged, more promising seminiferous tubules in non-obstructive azoospermia, but it cannot guarantee sperm. Outcome depends strongly on the underlying diagnosis and genetics, and even successful sperm retrieval does not guarantee fertilisation, embryo development or pregnancy.

The procedure should therefore be coordinated with an experienced embryology laboratory and a clear IVF/ICSI plan, including what will happen if sperm are found and whether sperm will be frozen for future use.

What to bring for consultation

Bring these if available:

• Semen analyses documenting azoospermia/pellet search.
• FSH, LH and testosterone.
• Karyotype and Y-microdeletion report.
• Previous biopsy/TESE/micro-TESE operative and pathology reports.
• Previous sperm-freezing/embryology records.
• Blood-thinner list and pre-anaesthesia medical records.
• Partner’s IVF plan and expected oocyte retrieval date.

FAQs

Related reading

• Non-Obstructive Azoospermia
• Azoospermia: No Sperm in Semen
• High FSH in Male Infertility
• Y-Chromosome Microdeletion Test
• Klinefelter Syndrome and Infertility
• Urologist in Latur

References

• 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
• 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/documents/Guidelines/PDF/2024%20Guidelines/Male%20Infertility%20Unabridged%20Final.pdf