What Is ICSI?
Intracytoplasmic Sperm Injection (ICSI) was first successful in 1992. It is a specialised form of In Vitro Fertilisation (IVF) where a single sperm is injected directly into a mature egg as opposed to IVF where thousands of sperm are mixed with a single egg, and one sperm enters the egg without assistance.
Who is ICSI for?
ICSI is not needed for every couple and is generally recommended for patients with:
- An increased risk of fertilization failure due to a sperm disorders (such as very low sperm concentration or motility, high abnormalities or positive anti-sperm antibody binding),
- Previously failed IVF cycles
- Following surgical sperm retrieval.
How does ICSI it work?
ICSI works in the same way as IVF where women undergoing treatment will be given fertility drugs to try and produce more than the one egg usually produced in each cycle. These stimulation injections are given daily subcutaneously (under the skin) and you will be taught and how to do this before you start. A second type of medication given as a nasal spray or injection, depending on the protocol, is also provided to stop you ovulation (releasing the eggs) before they are ready for collection.
Over a period of about two weeks, whilst taking these injections you will be scanned and have blood tests daily or on alternate days depending on your protocol. It is important to monitor the development of the follicles, the small collections of fluid where eggs develop within the ovary, to correctly plan the day of egg collection. This also enable us to increase/decrease the doses of medicine depending on the response to treatment which helps reduce the side effects of medication and optimize your chances of success.
When the scans and blood tests show that the eggs are ready for collection, a final hormonal injection of human Chorionic Gonadotrophin (hCG) is given approximately 36 hours pre-operatively. This stimulates the eggs to reach maturity.
The eggs are collected by ultrasound guided vaginal aspiration of the follicles. In the aspirate of the follicle the embryologist should be able to identify an egg. It is difficult to determine the number of eggs that will be collected until collection procedure. In rare cases no eggs are collected.
To minimize discomfort this is usually performed under light general anaesthetic or sedation.
In the laboratory, the embryologist will prepare the sperm for ICSI.
After egg collection the mature eggs are specially treated to remove the cumulus cells surrounding them. A single sperm is selected and drawn up into a very fine, specially prepared glass needle. The embryologist then injects this sperm directly into the egg, under microscopic control, using specialized instruments.
Sometimes IVF/ICSI treatment results in the creation of more embryos than required for an embryo transfer. It is recommended that if they are good quality embryos they can be frozen for future use. This avoids the need for further fresh stimulation.
The frozen embryos are transferred in a natural or medicated cycle.