microTESE sperm retrieval

What microTESE is

microTESE stands for microdissection testicular sperm extraction. It is an operation performed under a high-powered operating microscope to search the inside of the testicle for the small pockets of tissue that are still producing sperm, in men who have no sperm in the ejaculate.

The principle is straightforward. In non-obstructive azoospermia, sperm production is not uniformly absent — it is patchy. Some seminiferous tubules are empty and thin; others are wider and more opaque because they contain developing sperm. At 20 to 25 times magnification, those differences are visible to a trained eye. The surgeon can then take tissue from precisely the areas most likely to yield sperm.

Why it is better than a conventional biopsy

A standard TESE takes random samples and hopes to hit productive tissue. microTESE examines the whole testis systematically and samples selectively. This has two consequences that matter a great deal:

• A higher chance of finding sperm. Targeted sampling finds sperm in men in whom random biopsy does not.
• Far less tissue removed. Random biopsy removes considerably more testicular tissue, which risks damaging testosterone production and causing long-term hormonal problems. microTESE removes a fraction of that volume.

The second point is often overlooked. Men with non-obstructive azoospermia frequently already have borderline testosterone levels, and preserving what testicular function remains is important for their long-term health, not just for this fertility attempt.

Who it is for

microTESE is indicated for men with confirmed non-obstructive azoospermia — where the testicles produce little or no sperm, rather than where sperm are blocked from getting out. Typical situations include Klinefelter syndrome, previous chemotherapy or radiotherapy, undescended testicles, Y chromosome microdeletions of certain types, previous mumps orchitis, and idiopathic testicular failure.

It is not the right operation for obstructive azoospermia, where simpler techniques will reliably obtain good-quality sperm, or where reconstruction may restore natural fertility. Establishing which type you have is the purpose of the initial assessment.

Some Y chromosome microdeletions predict that no sperm will be found. Genetic testing before surgery is therefore essential — it can spare you an operation that cannot succeed.

Preparation

Before surgery you will have confirmed azoospermia on at least two properly centrifuged samples, a hormone profile, genetic testing including karyotype and Y microdeletion analysis, and a scrotal examination and ultrasound. Where hormone levels can be improved, a period of medical treatment beforehand is sometimes recommended.

Timing is planned in one of two ways: synchronised with your partner's egg collection so that fresh sperm can be used, or performed in advance with any sperm found frozen for later use. Each approach has advantages, and we will decide together with your fertility unit.

The operation and recovery

microTESE is performed under general anaesthetic as a day case in most men. A small incision is made in the scrotum, the testis is opened, and the tubules are examined systematically under the microscope. Selected tubules are sampled and passed immediately to an embryologist, who examines them for sperm while you are still in theatre — which allows the search to continue and, if needed, to extend to the other testis.

You will have discomfort, swelling and bruising for one to two weeks. Supportive underwear helps. Most men return to desk work within a few days to a week and avoid heavy lifting, cycling and sport for around three to four weeks. Precise guidance is given in your discharge plan.

Risks

As with any operation there are risks, which are discussed in full at consultation and in your consent process. They include bleeding and haematoma, infection, pain that persists longer than expected, a reduction in testosterone production, and testicular atrophy. The most important thing to prepare for, however, is not a surgical complication but the possibility that no sperm are found. That outcome, and what you would do next, should be discussed before the operation rather than in recovery.

My experience

I established the largest male infertility service from south of the Thames to the south coast at Guy's Hospital in 2012, specialising in microsurgery and onco-fertility, and I run a national training fellowship in male infertility surgery. I teach andrology and male infertility on the BAUS FRCS(Urol) course and for the British Fertility Society and the RCOG, and co-lead the AGOUR course, one of the largest andrology and infertility courses in the world. I accept tertiary referrals including men in whom retrieval has already been attempted elsewhere.