What Is TESE And Who Is TESE Suitable For?

17 Nov 2022

For couples wanting to conceive a child, there is a likelihood of infertility. In about half of infertility cases, the male partner will be a major or contributing, factor to the problem. Of these men, about 10% will produce semen with no detectable amount of sperm. This is a condition known as azoospermia. 

Semen is the ejaculation that comes from a man’s penis after having achieved orgasm. When this milky white substance is spun in a centrifuge and examined under a high-powered microscope to reveal an absence of sperm, then the male is diagnosed with azoospermia. 

What causes azoospermia

There are two main reasons for this condition. The first could be a blockage or missing connection somewhere along the reproductive tract that is preventing sperm that is being produced in the testes from exiting. It could also be due to the man having undergone a vasectomy. This means the male does have sperm but they are blocked from being released through semen. It is referred to as obstructive azoospermia. 

The other likely cause of azoospermia is if there is a defect in the testicles or other condition that is causing poor or no production of sperm. This is referred to as nonobstructive azoospermia. 

What is TESE?

TESE stands for Testicular Sperm Extraction. It is a surgical sperm retrieval procedure that is used in the treatment of men who may have azoospermia. It is primarily used to treat those with obstructive azoospermia. Removal of testicular tissue occurs to find sperm. 

How TESE is done

It is a minor surgical procedure that allows for sperm to be collected directly from the testes. It can be conducted under general, local or moderate anaesthesia. During the procedure, samples of tissue are taken from the testicles through a tiny incision made into the scrotum. This tissue sample is sent for analysis without the doctor knowing the likelihood of sperm being found. If healthy sperms are found, they are extracted in the lab and contained in vials. They may be used directly for fertilising an egg through IVF or ICSI or frozen for later use.  

When used for in vitro fertilisation or IVF, it means that a good number of sperms has been found and are added to the eggs to allow for fertilisation to occur. However, in many cases of TESE, the azoospermia condition means that there is a low sperm count. This may result in ICSI treatment being recommended. 

ICSI or intracytoplasmic sperm injection involves the selection of just a single sperm that is directly injected into an egg using a microscopic needle. After this direct fertilisation, the resulting embryos are allowed to develop for a few days before either being transferred into the woman’s uterus or being frozen. 

What is microTESE?

Microsurgical testicular sperm extraction, or microTESE, is a variation of TESE designed to collect sperm from men diagnosed with nonobstructive azoospermia. The sperm is retrieved from the coiled structures that are the seminiferous tubules of the testes. Seminiferous tubules make up most of the testes; as much as 90% of testicular tissues. It is within their walls that sperms are produced. 

This procedure is recommended when doctors find that the man has adequate levels of testosterone during hormone testing, however, other exams conclude that his testicles are producing an inadequate amount of sperm. It is also used to treat those that are still diagnosed with nonobstructive azoospermia despite having undergone fertility treatment with no successful results. 

How is microTESE done?

During this procedure, the patient is placed under general anaesthesia. The doctor then makes a very small incision along the midline of the scrotum. This will provide access to a high-powered microscope to look inside the testes and identify seminiferous tubules that are swollen and likely have sperm. A tissue sample is then taken from these tubules before the incision is closed. The procedure may be repeated on the other testicle. 

A lab technologist will then further examine the tissues under a standard microscope to see if there are any sperm. If found, the sperm are extracted to be used in IVF or ICSI, or frozen for later use. 

Who are TESE and microTESE suitable for?

As said, TESE is usually done on men with obstructive azoospermia, while microTESE is better suited for those with nonobstructive azoospermia. In both cases, the goal is to check if there are any sperm to be found in the testicular tissue and extract them for use in IVF or ICSI, or to be frozen for later use. Both procedures are outpatient and require a care partner to look after the patient for a few days afterwards. 

Note that this sperm is not generally used for intrauterine insemination (IUI). This is whereby the sperm is released into a woman’s uterus or fallopian tubes to find its way to the egg and fertilise it. The sperm is not used for IUI as they are extracted directly from testicular tissues and have not learnt how to swim yet. 

There are several ways to treat azoospermia, but where treatments like hormone therapy or surgery to repair blockages in the male reproductive system do not work, these procedures may be considered. It is also often recommended in cases whereby the patient does not have time to wait for such treatments. 

Men that need to undergo cancer treatment but have been diagnosed with azoospermia will be advised to undergo this procedure so they can have viable sperm samples preserved in case they want to try for a biological child later. When carried out by a skilled surgeon and lab technologist, these procedures can have a high success rate. 

What is TESA?

Testicular sperm aspiration, or TESA, is used to retrieve sperm in cases of obstructive azoospermia whereby the males do produce normal levels of sperm but have a blockage or other defect preventing their release. In this case, no incision is made. Under local anaesthesia, a needle is inserted into the testicle and tubules to suction out sperm. It is a simple procedure that requires no stitches. If the procedure fails, the patient may then be advised to undergo TESE.