Testicular biopsy is used to collect sperm directly from the testis or the tubes conveying sperm from the testis. The testis might be creating sperm, which may not be present in the ejaculated semen.
This may be for a number of reasons such as:
- An absence of the tubes that convey the sperms from the testis -this may due to having had a vasectomy or it can occur in patients with cystic fibrosis.
- A blockage of the tubing -this may be due to infection.
There are two common approaches to testicular biopsy:
Percutaneous Epididymal Sperm Aspiration (PESA)
PESA is when a fine needle is inserted into the tubes that convey the sperm out of the testis. One area of this tubing, the epididymus, is a natural reservoir for sperm and is therefore a good place to aspirate them from.
If a PESA is not possible or no sperm are identified then the procedure progresses onto testicular biopsy. This procedure involves the removal of very small pieces of tissue from the testis -the Embryologist then processes the biopsies with a view to finding motile sperm.
The testicular biopsy procedures are performed under local anesthetic. The procedure takes about 15 minutes.
Sperm suitable for ICSI are sometimes not found. It is prudent, therefore, to have some form of sperm as “back-up” in order that the ICSI treatment cycles not have to be abandoned.
The sperm recovered by either of these techniques is only suitable for use with ICSI. Once the ICSI has been completed and sperm remaining, of good quality, may be frozen for use with future ICSI cycles.
The success rate for ICSI is typically 30 – 55% at BFC per treatment cycle. However, the success rate is dependant on many factors, such as the age of the woman.