Intracytoplasmic Sperm Injection
Intracytoplasmic Sperm Injection (ICSI) has revolutionized the treatment of male factor infertility by allowing men who were previously incapable of producing adequate sperm, to father genetically related children.
ICSI involves the placement of a single sperm directly into the egg using a microscopic pipette. Men normally produce millions of sperm in each ejaculate. These sperm “swim” through the cervical opening and into the tubes to the site of fertilization. Some men have sperm defects such as a reduced sperm count, deformed sperm, or sperm that cannot swim effectively. When any one of these abnormalities are present, it can prevent normal fertilization. ICSI bypasses sperm defects because a single sperm is “selected” and placed inside the egg. ICSI is performed as a part of the IVF cycle. During IVF, the eggs are retrieved from the ovaries and taken to the embryology laboratory. In ICSI, a stereomicroscope is used to manipulate the egg(s). The egg is held in place while it is punctured by the micro pipette, and the sperm is inserted. IVF/ICSI is used in cases of severe male factor infertility and in other conditions such as failed fertilization in previous IVF cycles.
Couples have the option of a vasectomy reversal or IVF-ICSI with epididymal or testicular sperm extraction. Age of the female partner and length of time since prior vasectomy are important factors in decision-making. It can sometimes take 6-9 months to recover adequate sperm counts following vasectomy reversal. Also, the greater the length of time between the vasectomy and the reversal, the greater the chances are that the surgery will be unsuccessful or that anti-sperm antibodies will form, preventing the recovered sperm from penetrating the eggs without IVF-ICSI. Prior vasectomy, congenital absence of the vas deferens (i.e. no sperm in the ejaculate but normal testicular sperm production, also referred to as obstructive azoospermia): IVF-ICSI with either Microsurgical Epididymal Sperm Aspiration (MESA) or Testicular Sperm Extraction (TESE).
Microsurgical Epididymal Sperm Aspiration
With a MESA procedure, under local anesthesia and general sedation, an incision is made in the scrotum, exposing the epididymis, the tubules immediately adjacent to the testicles that collect the sperm. Using an operating microscope, an incision is made into these tubules and sperm is aspirated. Although millions of motile sperm can often be collected, this sperm has not acquired the ability to penetrate an egg and must be injected into eggs via the IVF-ICSI technique. The advantage of MESA over TESE for men with obstructive azoospermia is that sperm collected in this manner can usually be frozen, and even if his partner has to undergo more than one IVF procedure, the MESA should provide adequate sperm for all subsequent IVF procedures. A TESE or testicular sperm extraction is a procedure that involves directly aspirating the sperm from the testes or obtaining sperm from a testicular biopsy. It is usually performed under local anesthesia block and can be done as an office surgical procedure. The disadvantage is that in many cases, testicular sperm is much more scarce and therefore difficult to freeze. Usually, there is only enough sperm recovered for one IVF procedure, and if further IVF attempts are needed, the TESE procedure will need to be repeated.
Men with very poor sperm production in the testicles and no sperm in the ejaculate often demonstrate high blood FSH levels and sometimes low testosterone levels. The testicular size may be small. These men are usually considered to have relative testicular failure. TESE or testicular biopsy is usually the only option for them as there are no sperm in the epididymis and even testicular sperm production can be “patchy” and scarce within the testes. Men with this diagnosis who have been told they have no sperm on routine testicular biopsy frequently can be found, on further investigation, to have sperm present in a scattered distribution within the testicle. If so, these areas can be re-aspirated for IVF-ICSI with some degree of success, depending on the amount of sperm obtained.
Sertoli Cell Only Syndrome
Complete absence of sperm progenitor cells and absence of spermatogenesis is a rare condition. Sperm donation or adoption are the only options in these cases.