Intracytoplasmic Sperm Injection (ICSI) is one of the most significant advances in reproductive technology in the last 25 years. Fertilization of the egg in the laboratory during In Vitro Fertilization (IVF) requires more sperm than one might imagine. Unfortunately, there are many couples in which the male simply does not have enough active sperm to fertilize the egg. ICSI is designed to eliminate this concern. With ICSI, fertilization can be achieved with just a few sperm, so if any viable sperm cells can be found, ICSI is feasible. Furthermore, the sperm do not have to be normal. An abnormal, immature, or non-moving sperm will contain a normal complement of DNA - that is, the genetic package is intact. It is just the carrier that is not functional.
How is ICSI Done?
ICSI involves the use of specialized micro-manipulation equipment in the IVF laboratory. An egg is stabilized under the microscope with a special micro-pipette. A single sperm is then picked up into a second small needle-like pipette and injected directly into the egg. Sixteen to twenty hours later the egg can be evaluated and the presence or absence of fertilization noted.
What is the Effectiveness of ICSI?
Approximately 70 percent of eggs inseminated by ICSI will fertilize normally. Successful pregnancy rates are available from your physician, but we have clearly demonstrated that pregnancy rates are virtually identical whether eggs are fertilized by standard insemination techniques or by ICSI.
Are There Risks?
One risk of this procedure is damage to the egg. Not all eggs undergoing ICSI will fertilize normally, and not all embryos that result from this procedure will develop normally. Thousands of children have been born as the result of IVF cycles in which the eggs were fertilized by ICSI. There is still some question about whether or not male infants born as a result of this procedure will have normal fertility.
This procedure is useful when there is severe male factor infertility, when there has been failure of fertilization in a prior IVF attempt, or if testing suggests a deficit in the fertilizing capacity of the sperm. We also occasionally suggest “TBS ICSI” (TBS stands for “to be sure”). While rarely encountered, defects in sperm fertilizing function can occur. TBS ICSI assures that such a defect will not result in complete failure of fertilization at the time of the initial IVF attempt. For couples in which the male has never fathered a pregnancy, doing ICSI on a few of the oocytes retrieved at the time of an initial IVF procedure helps to ensure that at least some of the oocytes will fertilize.