ICSI - Intracytoplasmic Sperm Injection Procedure
Intracytoplasmic Sperm Injection (ICSI)
What is ICSI?
Intracytoplasmic sperm injection (ICSI) is very similar to conventional IVF in that gametes (eggs and sperm) are collected from each partner. The difference between the two procedures is the method of achieving fertilisation.
ICSI refers to the laboratory procedure where a single sperm is picked up with a fine glass needle and is injected directly into each egg . This is carried out in the laboratory by experienced embryologists using specialist equipment. Very few sperm are required and the ability of the sperm to penetrate the egg is no longer important as this has been assisted by the ICSI technique. ICSI does not guarantee that fertilisation will occur as the normal cellular events of fertilisation still need to occur once the sperm has been placed in the egg.
From a patient perspective, undergoing an ICSI treatment cycle is exactly the same as a conventional IVF cycle, and the same steps are involved.
Circumstances in which ICSI may be appropriate include:
- When the sperm count is very low
- When the sperm cannot move properly or are in other ways abnormal
- When sperm has been retrieved surgically from the epididymis (MESA/PESA) or the testes(TESE/TESA), from urine or following electro-ejaculation
- When there are high levels of antibodies in the semen
- When there has been a previous fertilization failure using conventional IVF.
From a patient perspective, undergoing an ICSI treatment cycle is exactly the same as a conventional IVF cycle. These step are described more fully under IVF.
- Stimulation of the ovaries to encourage development and maturation of the eggs
- Retrieval of the eggs
- Fertilization of the eggs and culture of the embryos
- Transfer of the embryos back into the uterus.
Severe male infertility isn’t the only reason ICSI-IVF is used. Other evidence-based reasons for ICSI include,
- Previous IVF cycle had few or no fertilized eggs: Sometimes, a good number of eggs are retrieved, and sperm counts look healthy, but no eggs get fertilized. In this case, during the next IVF cycle, ICSI may be tried.
- Frozen sperm are being used: If the thawed sperm don’t appear especially active, ICSI-IVF may be recommended.
- Frozen oocytes are being used: Vitrification of eggs can sometimes cause hardening of the egg’s shell. This may complicate fertilization, and IVF with ICSI may help overcome this hurdle.
- PGD is being done: PGD (pre implantation genetic diagnosis) is an IVF technology that allows for genetic screening of embryos. There is concern that regular fertilization techniques may cause sperm cells (who have not fertilized the egg) to “hang around” the embryo, and that this may interfere with accurate PGD results.
- IVM (in vitro maturation) is being used: IVM is an IVF technology where eggs are retrieved from the ovaries before they completely mature. They go through the final stages of maturation in the lab. Some research has found that IVM eggs may not become fertilized by sperm cells at rates comparable to traditional IVF. More research is needed, but it may be that IVM with ICSI is a good option.