Advances in assisted reproductive techniques now allow pregnancy to occur with very few sperm. IUI, or Intrauterine Insemination, works by placing washed and healthy sperm directly into the uterus. In Vitro Fertilization or IVF, involving fertilizing the egg outside of the body, is also possible with advanced sperm extraction and aspiration.
In men with severely reduced sperm count, the sperm obtained from the ejaculate may not be suitable for IUI as they tend to be low in number and motility. These sperm, on the other hand, do quite well with IVF/ICSI, with comparable pregnancy outcomes (30 to 40%) with IVF.
Some groups of men may require IVF/ICSI to father children, including:
Patchy areas of sperm production may be present, but the sperm produced are so few that none survive transit to the outside of the body. Testicular tissue may be obtained directly from the testis, and sperm, if present, can then be extracted in the laboratory for IVF/ICSI. The TESE procedure is identical to testis biopsy; a small incision is made on the scrotum, and one to several small testis tissue samples are submitted to the lab for extraction. Since the introduction of micro-TESE, we no longer perform routine TESE in men with non-obstructive azoospermia.
In a more refined approach. Sperm-containing tubules have a different appearance when examined under high magnification; this difference allows for the selective removal of only sperm-containing tubules and avoids unnecessary tissue removal without sperm. Micro-TESE has a significantly higher success rate than traditional TESE.
Micro-TESE is not a testis biopsy. Operative time is at least 1 to 2 hours, as the urologic surgeon must painstakingly examine the testicular content before tubule excision. The inability to retrieve sperm with micro-TESE effectively ends our effort in helping men achieve biological parenthood; as such, no effort is spared to reach a definitive conclusion. Both testes are explored if necessary.
A small needle is placed in the epididymis or testis, and a small number of sperm are obtained. Both procedures are easily performed in the office under local anesthesia. Given that the collection method is via needle, only a small number of sperm are obtained, enough to be immediately used with IVF but not enough for cryopreservation.
The advantages of PESA and TESA are their ease of performance and the lower cost, while the disadvantages are the small number of sperm obtained and the need to coordinate it with egg retrieval.
Like micro-TESE, MESA is an operating room procedure in which the engorged epididymis is examined under an operating microscope. The epididymal fluid with sperm is then collected for immediate use or cryopreservation. MESA is expensive, and given the ease of performing aspiration with a comparable pregnancy rate, it is rarely used.
The advantages of TESE and MESA are the large number of sperm retrieved for cryopreservation, which often eliminates the need for future retrieval procedures. The disadvantages are that these procedures are more involved and have higher costs.
The common denominator of all the above is that the sperm retrieved are functionally immature and small in quantity compared to a normal ejaculate. Although these sperm are capable of fertilization and achieving a normal pregnancy, they cannot penetrate eggs on their own, and thus, IVF/ICSI is necessary to initiate fertilization.
Please get in touch with us if you have any questions regarding these procedures.
