Intracytoplasmic Sperm Injection (ICSI) is performed as part of an IVF procedure to treat male factor abnormalities. After egg retrieval, using a glass needle, a single sperm is selected by and injected into the egg. This often enhances fertilization to help couples conceive when the man has low sperm concentration, motility, or abnormal shapes. The Follas Center of Reproductive Medicine, our adjacent office-based facility, has state-of-the-art equipment to offer this option to our patients undergoing IVF.
Intracytoplasmic sperm injection, or ICSI, is a form of micro-assisted fertilization where the nucleus (genetic material) of the sperm is injected directly into the egg. It is used mostly in cases where the sperm have poor motility. Below is a graphically enhanced photo of ICSI. The holding device is on the left, the egg is in the center of the screen (the nucleus of the egg is in the very middle with an outer shell,) and the injection needle is on the right side of the screen. The sperm DNA is not visible, as it is very small.
Traditional IVF does not usually use ICSI. In a traditional IVF cycle, the eggs are retrieved from the female and a sperm sample is obtained from the male. The egg(s) are then placed in a culture dish in the laboratory and the sperm are then placed in the dish. The sperm are then allowed to naturally fertilize the eggs, just as they would in the human body. The fastest, luckiest sperm fertilizes each egg. An egg is only fertilized by one sperm. This process occurs over a period of usually five to ten hours. Occasionally, even with good sperm motility, zero or very few eggs will fertilize. Some eggs have tough shells or there may be underlying sperm problems. In this case, it is usually a good idea to try another IVF cycle and use ICSI.
ICSI is performed by a highly skill embryologist and involves selecting a sperm, picking it up with a specialized micro-needle and injecting it directly into the egg. You can think of it as the laboratory equivalent of a “pre-arranged marriage.” This process guarantees placement of the sperm DNA within the egg, though it does not guarantee successful fertilization, as there may be underlying genetic problems with either the sperm or the egg. Below is an actual photo of the ICSI procedure. If you are further interested, here are movies on ICSI showing the complete ICSI procedure.
ICSI is a very effective procedure to assist fertilization for couples with sperm problems, and has been in widespread use around the world since the early 1990’s. There are approximately 150,000 IVF cycles done each year in the US and about half of them use ICSI to achieve fertilization.
There have been many studies done looking at genetic malformations when ICSI is used. To date, there have been no definitive studies that have shown a clear connection. There have been a few studies which have suggested an increase in the incidence, though these studies were not well done and frequently compared malformation rates today with non-IVF numbers from many years before. Unfortuately, the rate of birth defects has been going up in our country, just as the incidence of infertility has been going up. This is most likely related to chemical toxins in our air, water, and skin.