Testicular Tissue Freezing

Since the advent of ICSI, it has been possible to achieve fertilisation in couples where men have extremely low numbers of sperm.
An individual sperm can be injected into an egg to achieve fertilisation.


Embryos resulting from ICSI can then be replaced in the partner's uterus at the appropriate time of her menstrual cycle, in an attempt to achieve a pregnancy.


A small proportion of men produce no sperm in their ejaculate. This condition is known as azoospermia.

In most cases azoospermia results from an obstruction in the vas deferens (the tube which transports sperm from the testis into the ejaculate).

The commonest reasons for an obstruction in the vas are previous vasectomy operation, an infection or congenital absence of the vas deferens. In nearly all cases, sperm production still continues within the testis, and therefore tissue removed from the testis should normally contain sperm that can be used for lCSl.

Until recently sperm extraction from the testis was performed using needles or microsurgical techniques, and the extraction had to he performed on the day of the partner's egg collection in order to use fresh sperm for ICSI.

This could mean repeated aspirations of sperm, or surgical removal of sperm from the male partner each time the woman had an egg collection procedure for ICSI.

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It is now possible to freeze testicular tissue with one small surgical procedure being performed, and several attempts at ICSI can then be carried out following this procedure.

The advantage of this technique is that the risk of infection, and complications with bleeding are decreased following a single procedure, as compared to multiple procedures.

What is involved?

Initial diagnostic investigation in the form of a blood test to screen for chromosorne abnormalities, cystic fibrosis, and a clinical examination for the male is necessary before proceeding with testicular biopsy. If an abnormality is discovered, appropriate counselling will be arranged.

The male partner is admitted to hospital as a "day surgery" case, and the procedure can be performed under local or general anaesthetic, depending on the patient's preference.

An incision, less than half a centimetre in length, is made in the testicle and a tiny fragment of testicular tissue is extracted (approximately 2-3mm) for examination and freezing. This section of tissue is then divided into 5 or 6 further sections, so that one section can be tested on the day of the surgery to check for the presence or absence of normal sperm. The remaining sections are frozen to be used subsequently for ICSI.

Advantages of freezing testicular tissue over testicular sperm aspiration on the day of egg collection are as follows:

	The surgical procedure involved with testicular biopsy is an extremely simple procedure compared to microsurgical techniques for sperm extraction. Testicular biopsy has less risk of bleeding and infection than needling techniques, which are performed through the skin without direct vision. Surgery can be performed at the conivenience of the male partner and may be performed several months prior to any ICSI procedure. Microscopic examination of the tissue on the day of the initial procedure can give an accurate diagnosis of the reason for azoospermia. When no spem are present in the biopsy specimen, counselling for donor sperm can he carried out well in advance of any treatment being performed on the female partner, thus avoiding unnecessary drug stimulation and surgery. For single men, prior to cancer chemotherapy or radiotherapy or even prior to the removal of the testicles in the case of testicular cancer, it is possible to freeze testicular tissue When the man decides to become a father his testicular tissue can then be used to fertilise his partner's eggs using ICSI.