Sperm aspiration is the group of procedures used to obtain viable sperm from the male reproductive tract. The collected sperm are intended specifically for use with intra-cytoplasmic sperm injection (ICSI). Couples often ask if the sperm harvested by these techniques can be used for insemination. The answer is that there is not enough sperm retrieved to perform intrauterine insemination (IUI) regardless of the technique used to harvest the sperm. Usually enough sperm can be obtained for ICSI and freezing. At least 5-8 million mature (passed through the epididymis) motile sperm with normal morphology are required for IUI. Sperm aspiration is reserved for men who have the most severe types of male infertility including no sperm in their ejaculate (azoospermia) or sperm that are not motile or are dead (necrospermia).
There are two specific reasons why sperm may be absent from the semen thus leading to the need for sperm aspiration. One reason is obstructive azoospermia which is the result of a blockage in the male reproductive tract. The second reason is that sperm production in the testicle is normal but the sperm is trapped inside the epididymis.
Non-obstructive azoospermia is the result of severely impaired or non-existent sperm production. It is precisely these situations that require advanced reproduction technologies such as ICSI to establish a pregnancy.
Four techniques can be used to obtain sperm
These procedures have their advantages and disadvantages. Consequently, not all the techniques are applicable to every situation. Comprehensive knowledge and understanding of the cause of infertility and pathophysiology of the disease process are essential before a procedure can be recommended and performed.
Sperm harvesting techniques used to obtain sperm from men with obstructive azoospermia:
Microsurgical Epididymal Sperm Aspiration. This is the optimal way of obtaining sperm in those men with a reproductive tract blockage, such as after a vasectomy or congenital absence of the vas deferens. The epididymis (organ above the testicle where the sperm are stored) is isolated through a half inch incision made in the scrotal skin. An operating microscope is used to examine the very small tubules of the epididymis that contain the sperm. A dilated tubule is opened then the fluid is collected and examined for the presence and quality of sperm. All of the sperm containing fluid is collected and taken to the IVF lab for processing, use and freezing. If the fluid is devoid of sperm or only dead sperm are found, then another area of the epididymis is sampled. This is done until enough sperm is obtained to use and store for future use.
A needle is placed into the epididymis in the hope that a pocket of sperm will be found and aspirated.
Testicular Sperm Extraction. It is an open procedure performed under direct vision and therefore minimizes potential complications. A small piece of testicular tissue is removed through a half inch skin incision. The tissue is placed in culture media and morsalized into tiny pieces. Sperm is liberated from within the seminiferous tubules where they are produced and are then extracted from the surrounding testicular tissue. This can be an exhaustive process depending on the degree of sperm production. This procedure can be performed in an operating room or office procedure room using a local anaesthetic. We recommend mild sedation for patient comfort. Sperm harvested using TESE can be frozen and stored for later use.
Testicular Sperm Aspiration. This is a needle biopsy of the testicle. It is an office procedure performed under local anaesthesia. A small incision is made in the scrotal skin and a spring loaded needle is fired through the testicle. While it is possible to retrieve sperm using this technique, the amount is often low because the needle cuts a thin sliver of tissue.
Sperm aspiration via the appropriate technique is usually a successful, minimally invasive procedure that allows men who make very few sperm to conceive a child of their own. Our goal is to provide the safest, most effective patient care and to collect as much good quality sperm as possible to minimize the need for multiple surgeries in the future.