These can be separated into two categories based on the primary cause: obstructive azoospermia, in which there is a blockage preventing sperm entering the seminal fluid, and non-obstructive azoospermia, in which there is no blockage. If your semen analysis results indicate that there is very little or no sperm in the ejaculate, you will be asked to undergo further testing to determine whether the underlying cause is an obstruction. Research also indicates that poor sperm quality is associated with a greater risk for certain genetic conditions. Hence, you will be asked to undergo further tests to evaluate those risks.
Obstructive azoospermia can be caused a failure of development of the sperm passages (congential absence of the vas deferens), blockage of the sperm passages or previous vasectomy operation.
Although vasectomies and certain other obstructions can be corrected, the corrective surgery is not always successful or permanent. Other obstructions, such as a congenital absence of the vas deferens, cannot be surgically corrected.
Non-obstructive azoospermia can be caused by a congenital problem (from birth) or can be a result of injury, previous disease (e.g. mumps) or exposure to radiation (e.g. X-ray). Further analysis of such men by testicular biopsy reveals that many (roughly 40%) have areas in the testes containing plenty of normal sperm that do not pass into the seminal fluid even though there is no blockage. In cases of non-obstructive azoospermia further tests will be performed to assess the degree of sperm production and in some cases you will be prescribed medications to improve the quality and number of sperm prior to surgery.
Minimally invasive surgical sperm retrieval techniques (PESA or TESA) can be used to retrieve sperm in cases of obstructive azoospermia and in cases of non-obstructive azoospermia where there is believed to be reasonable sperm production. In cases of non-obstructive azoospermia where there appears to be very little sperm production, a more invasive surgical technique performed by a consultant uroglogist Is more suitable (micro-dissection TESE). PESA and TESA are performed under mild intravenous sedation whilst micro-dissection TESE is performed under general anaesthesia.
The surgeon attempts to retrieve sperm by inserting a fine needle into the epididymis at the upper area of the testis and applying gentle suction.
The surgeon first attempts to retrieve sperm directly from the testis by inserting a fine needle into the testicular tissue and gently aspirating small samples of tissue.
Under general anaesthesia, the surgeon makes an incision on the scrotum and both testicles are delivered. Each testis has an incision made and is examined under the operating microscope. Tubules containing sperm appear more dilated and opaque under the microscope. Such tubules are excised by the surgeon and given to the embryologist. The embryologist will tweeze out sperm from the tissue provided.
After PESA or TESA there will be a little bruising and tenderness of the scrotum for a day or two. As with any surgery, these procedures carry a small risk of bleeding, pain, bruising and infection at the site of the wound. Patients are advised to take complete rest for 24 to 48 hours to reduce the bleeding and swelling. They are also advised to wear tight underwear to reduce the swelling.
Most patients are able to resume their daily activities after two or three days. Taking over the counter painkillers, such as Ibuprofen, will also help with any discomfort and reduce swelling.
Patients will generally be informed on the same day whether sperm was retrieved. However, in certain cases a two day period of tissue incubation is required before sperm can be recovered.
Recovered sperm with good motility and normal morphology will be used immediately for treatment or frozen for future use. Patients undergoing surgical sperm retrieval will need to have ICSI performed to fertilise the eggs.
The chance of success by PESA or TESA in straightforward obstructive azoospermia cases is almost 90%. Please speak to your consultant for success rates in more complicated cases.
Men with azoospermia are at higher risk for certain inherited conditions as mentioned above. Therefore, the following additional testing is recommended:
We perform a complete chromosomal analysis to check for gain or loss of any chromosomes as well as structural defects, including rearrangements (translocations), duplications, deletions and inversions. Paternal transmission of chromosome defects can result in pregnancy loss, birth defects, infertility in male off spring and other genetic conditions. Example conditions can include Klinefelter syndrome (XXY sex chromosomes) and the male XX syndrome.
Genetic defects on the Y (sex) chromosome are troublesome because they will inevitably be transmitted to sons. Men with non-obstructive azoospermia will be advised to check for gene deletions on their Y chromosome. The presence of such deletions will give rise to infertility or sterility in male offspring, only in adulthood.
Cystic fibrosis (CF) is a serious congenital disease leading to severe respiratory problems in infants. Two in three men with CF will have a congenital absence of the vas deferens. In such cases we will test both partners for CF gene mutations. If the male is a carrier of the CF gene mutation but the female is not, the risk of their offspring developing CF is 1 in 300 (the risk in the general population is 1 in 600). If both partners carry the CF gene mutation then preimplantation genetic diagnosis (PGD) is recommended. In all such cases specialist genetic counselling is advised and can be arranged by the clinic.