What is (ICSI) Intracytoplasmic sperm injection?
ICSI-IVF is a specialized form of in vitro fertilization that is used mostly commonly in cases of severe male infertility, after repeated failed fertilization attempts with conventional IVF, or after egg freezing (oocyte preservation)
Intracytoplasmic sperm injection is an in vitro fertilization (IVF) procedure in which a single sperm cell is injected directly into the cytoplasm of an egg.
There are several differences within classic IVF and ICSI. However, the steps to be followed before and after insemination are the same. In terms of insemination, ICSI needs one only sperm cell per oocyte, meanwhile IVF needs between 50 and 100 thousands. This is due to the fact that in IVF acrosome reaction has to take place and thousands of sperm cells have to be involved. Once fertilized, the egg is transformed into a pre-embryo and it has to be transferred to the uterus to continue its development.
Uses of Intracytoplasmic sperm injection :
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 fertilisation failure using conventional IVF.
ICSI-IVF is typically used in cases of severe male infertility, including:
- Very low sperm count (also known as oligospermia)
- Abnormally shaped sperm (also known as teratozoospermia)
- Poor sperm movement (also known as asthenozoospermia)
If a man does not have any sperm in his ejaculate, but he is producing sperm, they may be retrieved through testicular sperm extraction, or TESE. Sperm retrieved through TESE require the use of ICSI. ICSI is also used in cases of retrograde ejaculation if the sperm are retrieved from the man's urine.
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 (preimplantation 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.