The PESA and TESA methods of sperm retrieval
There are two methods of retrieving sperm surgically.
PESA (percutaneous sperm aspiration)
This is the first choice (if possible) to collect sperm. A fine needle is inserted through the scrotum into the head of the epididymis and sperm are obtained by gentle suction. After each sample is collected, it is examined under the microscope to confirm the presence of sperm.
TESA and TESE (testicular sperm extraction)
A fine needle is inserted into the testis and sperm is aspirated (TESA) by gentle suction and examined under the microscope to see if sperm is found (TESA). If sperm is not found by TESA then a small tissue sample (testicular biopsy) is taken through a small incision in the scrotum and testis, sperm can then be extracted from the tissue (TESE). Successful sperm recovery would be missed in approximately 25% of cases if only a single testis had been sampled.The cut is stitched back together with a couple of stitches, which self dissolve in about 10 days. Finding sperm in the testicular tissue can be a laborious process.
Surgically retrieved sperm are immature and incapable of fertilization by conventional means. Fertilization is achieved using ICSI, this involve injecting a selected sperm into the cytoplasm of a mature egg. Surgical sperm retrieval from the epididymis should be the first line in obstructive azoospermia, it yields a larger number of sperm mostly motile comapred with TESA. If no sperm is retrieved from PESA then TESA should be performed. For non-obstructive azoospermia, epididymal sperm can never be retrieved, TESA or open testicular biopsy should be performed.
Surgical sperm retrieval is a minor surgical procedure with low rate of complication. After the operation, You may feel discomfort, bruising and tenderness of the scrotum for 24-48 hours. This will be relieved with painkillers such as paracetemol or codeine tablets. There is a small risk of infection and bleeding after the procedure. A firm scrotal support is recommended until the discomfort subsides. The long-term effects of repeated testicular biopsy are poorly understood.
Any spare sperm or testicular tissues may be frozen for later use, thus avoiding a repeat of surgical sperm retrieval procedure.
In case no sperm is found, the couple may either decide to cancel the egg collection and abandon treatment altogether, or proceed with the egg collection and inseminate the eggs with donor sperm if this has been discussed and agreed before hand as a 'backup'.