Surgical Sperm Retrieval: TESE, MicroTESE and PESA Explained
For men with azoospermia — no sperm in the ejaculate — the ability to retrieve sperm directly from the reproductive tract has transformed the outlook for biological fatherhood. Surgical sperm retrieval, when combined with intracytoplasmic sperm injection (ICSI), has helped thousands of men with previously untreatable infertility become biological fathers.
Three main techniques are used: PESA, TESE, and microTESE. Understanding the differences helps couples make informed decisions and choose the most appropriate centre for their care.
PESA: Percutaneous Epididymal Sperm Aspiration
PESA is used primarily in men with obstructive azoospermia — where sperm are produced normally but cannot exit due to a blockage. A fine needle is passed through the scrotal skin into the epididymis (the coiled tube where sperm mature and are stored), and fluid containing sperm is aspirated.
PESA is minimally invasive, can usually be performed under local anaesthetic or light sedation, and is highly successful in obstructive azoospermia — retrieval rates typically exceed 90%. It can be performed on the day of egg collection for IVF, or sperm can be retrieved and frozen in advance.
PESA is generally not appropriate for non-obstructive azoospermia, where sperm production itself is impaired.
TESE: Testicular Sperm Extraction
TESE involves taking one or more small biopsies of testicular tissue, from which sperm are then extracted in the laboratory. It is used in both obstructive and non-obstructive azoospermia.
In obstructive azoospermia, TESE is highly effective. In non-obstructive azoospermia (NOA), standard TESE retrieves sperm in roughly 20–30% of cases — because sperm production is patchy and unevenly distributed throughout the testis. This is the limitation that microTESE was developed to address.
MicroTESE: Microscopic Testicular Sperm Extraction
MicroTESE is the gold standard surgical technique for non-obstructive azoospermia. It requires an operating microscope and a surgeon with specialist training in andrological microsurgery.
The testis is opened, and the surgeon uses the operating microscope at high magnification to systematically examine the seminiferous tubules — the tiny structures in which sperm are produced. Under magnification, tubules with active sperm production appear larger and more opaque than non-productive tubules. The surgeon selectively samples the areas with the highest probability of containing sperm.
This approach yields sperm in approximately 40–60% of men with NOA — a significant improvement over standard TESE. It also minimises the amount of testicular tissue removed, reducing the risk of post-operative testosterone deficiency.
Which Technique Is Right for You?
The decision depends primarily on the type of azoospermia you have:
| Type of Azoospermia | Recommended First-Line Retrieval |
|---|---|
| Obstructive (post-vasectomy) | Consider vasectomy reversal first; PESA or TESE if reversal not suitable |
| Obstructive (other causes) | PESA or TESE — high success rates |
| Non-obstructive | MicroTESE — gold standard |
Other factors that influence technique choice include your partner's IVF cycle timing, whether you wish to freeze sperm in advance, and the results of your hormonal and genetic workup.
Surgeon Experience Matters Enormously
The outcomes of microTESE in particular are highly dependent on surgical experience. A surgeon performing two or three microTESE procedures per year will achieve substantially lower retrieval rates than a high-volume specialist who performs this procedure regularly.
Professor Minhas and Professor Yap are among the UK's most experienced microTESE surgeons. Their retrieval rates reflect the international academic benchmark for this procedure, and they perform sperm retrieval in close coordination with leading IVF laboratories to maximise the utilisation of retrieved sperm.
Preparing for Surgical Sperm Retrieval
Before any sperm retrieval procedure, we will have completed a full andrological assessment including hormonal profile, genetic testing where indicated, and scrotal ultrasound. This allows us to counsel you accurately on the probability of retrieval and to coordinate timing with your IVF unit.
Contact London Andrology to discuss surgical sperm retrieval with Professor Minhas or Professor Yap.
