Intracytoplasmic Sperm Injection (ICSI) is a specialized form of In Vitro Fertilization (IVF) that is used for the treatment of severe cases of male factor infertility. ICSI involves the injection of a single sperm directly into a mature egg.
Before ICSI can be done, mature eggs must be retrieved from the female partner during a standard IVF cycle. The male partner’s semen sample is prepared in the lab to isolate as many healthy moving sperm as possible.
After allowing the eggs to rest for two to three hours following their removal, the tight outer coating of cells (cumulus) is removed from each egg. Only then can we be sure the egg is mature enough to undergo ICSI.
Immature eggs cannot be injected. However, they can be incubated for a further two to six hours and reassessed. If they mature in that time they can still be injected along with the other mature eggs. A special instrument is used to hold the egg in place. It is so small you can barely see the tip with the naked eye.
A thinner, sharp, needle-like instrument is used to pick up a single normal appearing sperm. With great precision, the needle is inserted through the egg’s outer coating (the zona pellucida) and into the egg itself. The sperm is slowly injected into the egg, and the needle is removed, leaving the sperm behind.
The injected eggs are placed in an incubator overnight and checked the next morning for signs of fertilisation.
After an additional 24 hours, we can determine how many have divided and gone on to form embryos. Not all eggs fertilise, and not all fertilised eggs become embryos. As with standard IVF, the number of embryos replaced into the uterus depends on the woman’s age and medical history.
Provided they appear healthy, additional embryos can be frozen if desired. The potential improvement in fertility that this type of treatment may yield depends on the woman’s age, diagnosis and the initial male semen analysis, and should be discussed with your specialist
Couples who have had poor or no fertilisation during standard IVF, as well as men who have:
