Testicular sperm extraction
Testicular sperm extraction is a minimally invasive technique reserved as a final line option for severe male infertility just before sperm donation is considered. It involves the collection of sperm directly from the testis, in cases of azoospermia or in cases of obstruction or where ejaculation is not possible. These techniques are different from testicular biopsy, as they aim to obtain a sperm sample that will be used later to perform ICSI, unlike in the case of biopsy, which is entirely diagnostic and the collected samples are not salvageable.
The complexity and technical difficulty of applying the technique may vary based on the underlying cause of infertility, namely a simpler and more brief technique may suffice to obtain a viable sperm sample from a man with reproductive tract obstruction, but a more advanced and lengthy technique may be needed for a man with abnormal spermatogenesis.
Available testicular sperm collection procedures
The simplest available method, TESA is performed primarily on men with obstructive azoospermia, a history of prior vasectomy or reproductive tract infection. It is performed under local anaesthesia, lasts for approximately 10 minutes and is a low-cost method. The sperm collection is coordinated with the female partner’s oocyte pick-up procedure in order to fertilize the collected oocytes.
A similar alternative to TESA is percutaneous epididymal sperm aspiration (PESA), which is as effective as TESA, but has been reported to confer faster recovery (within hours) and return to daily activities, whereas patients that have undergone TESA report some irritation, pain and swelling after the procedure.
TESE is a more invasive procedure than TESA, whereby a small incision is made on the testis and a sample of seminiferous tubules is collected and examined for useable sperm. TESE is performed under sedation or local anesthesia and may be coordinated with oocyte retrieval or scheduled one day prior. Since it is reserved for more severe cases of azoospermia, donor sperm may also be prepared and kept on standby, in case no viable sperm is retrieved.
MicroTESE is an advanced technique performed on men with abnormal spermatogenesis and azoospermia. It involves the performing a small incision and selecting specific, individual enlarged seminiferous tubules, which are more likely to contain sperm. These precise surgical maneuvers are performed under the operating microscope.
MicroTESE is frequently coordinated with the partner’s oocyte retrieval procedure, with donor sperm sample being kept in reserve, in case no viable sperm is isolated from the partner. MicroTESE has improved sperm retrieval rates and is less damaging to the testis, since less testicular tissue is removed compared to TESE.