Surgical sperm retrieval should be performed only in centers having specialized staff and facilities for sperm / testicular tissue cryopreservation. Sperm retrieved by testicular biopsy procedures may be used for IVF (ICSI in particular), thus enabling azoospermic men to father children. Sperm derived from a biopsy may be used fresh (biopsy performed on the spouse / partner on the day of egg collection), or frozen and used when the female partnetr is ready for egg collection.
Surgical sperm retrieval procedures are:
· MESA - Microepididymal Sperm Aspiration
This procedure is indicated for men who do not have sperm cells in their semen due to the absence or blocking of the vas deferens. It is also suitable for men having been sterilized by vasectomy.
A small incision is made, then sperm is collected from the tubes of the epididymis with the aid of a dissecting microscope.
· PESA - Percutaneous Epididimal Sperm Aspiration
In this procedure, sperm are collected from the epididymis by aspiration through a fine needle. The procedure is simpler than MESA and has fewer side effects.
· TESE - Testicular Sperm Extraction
This is the procedure used for most patients. Testicular tissue
(seminiferous tubules) is removed form the testicles and then checked by the embryologist for sperm. Typically, motile sperm are used for IVF; however, if motile cells are not found, spermatids (immature sperm cells) may also be used. Although pregnancy rates using spermatids are quite low now, it is expected that scientific progress will help improve them in the future.
· TESA - Testicular Sperm Aspiration
In this procedure, a needle is used to aspirate the contents of seminiferous tubules. Less material is collected with this method, but is usually is enough for an IVF procedure.
THis method can be used successfully in patients with obstructive azoospermia.