TESE and MESA

Azoospermia, that is, the absence of both mature and immature sperm, is not rare in couples who have difficulty having a child.
When we find very few or no sperm at all in the semen analysis, mature sperm capable of fertilisation may be found in the man’s epididymis or testes. With a minor outpatient procedure on the man, the urologist can obtain sperm in several ways:

• MESA – Microsurgical epididymal sperm aspiration
  When the sperm ducts are completely blocked, no sperm are found in the semen at ejaculation. In this case, the sperm have to be taken from the epididymis. Under local anaesthesia, the epididymis is punctured under a surgical microscope with a small “butterfly” needle, and the sperm stored in it are drawn off. Because only a few sperm are obtained with this method, the eggs are, as a rule, fertilised by intracytoplasmic sperm injection (ICSI), to make sure that fertilisation takes place.
• TESE – Sperm retrieval by open biopsy of small pieces of the testes
  If no sperm are found in the epididymis, small pieces of testicular tissue are taken (testicular biopsy). This tissue is enriched with special nutrient media, and in this way the sperm inside the seminiferous tubules of the testicular tissue are isolated. These sperm are usually semi-mature, but they fertilise the eggs effectively with ICSI.

With these techniques, sperm can be found in up to 75% of cases.

Combining these methods with ICSI gives high fertilisation and pregnancy rates, even in cases that until now were considered hopeless. The pregnancy rate ranges from 38% to 52%.

The small biopsies are mostly taken with the help of a surgical microscope from different areas of the testes, to increase the chances of success. If sperm are found, they are frozen in liquid nitrogen at −196 °C, and part of them is thawed at a second stage, when the woman has her egg retrieval after ovulation has been triggered. In this way (cryoTESE), the woman is spared unnecessary treatment if no sperm are found.

• Other methods of obtaining sperm
  • a. Masturbation. In men whose semen contains sperm, the sample is usually collected in a sterile container (a urine sample pot); it is important to abstain from sex for 3–5 days before the test.
  • b. Electrical stimulation. When nerve damage means that ejaculation does not happen, the man can be helped with electrical stimulation. A small probe is placed in the anus to stimulate the nerve endings that lead to ejaculation. This method must be done under anaesthesia because it is painful. The exception is tetraplegia, in which there is no sensation in this area.