What is ICSI? 

The woman or person with ovaries undergoes ovarian stimulation with fertility medications to encourage the development of multiple eggs.

Once the eggs have matured, they are retrieved from the ovaries using a minor surgical procedure called transvaginal ultrasound aspiration.

On the same day as the egg retrieval, sperm is collected from the male/AMAB partner or a sperm donor.

In the ICSI procedure, a single sperm is selected and injected directly into the cytoplasm of each mature egg using a fine glass needle. This bypasses the need for sperm to naturally penetrate the egg's outer layer (zona pellucida).

After the injection, the eggs are incubated in a laboratory to allow fertilisation to take place. The fertilised eggs, now called embryos, are monitored for several days to assess their development.

Typically, after 3 to 5 days of development, the best embryos are selected for transfer into the uterus. This is done using a thin catheter inserted through the cervix.

If the embryo successfully implants in the uterine lining, pregnancy may occur.

After roughly two weeks a pregnancy test is taken. Dependent on the results, those with a positive test are then referring to their doctors.

Compared to IVF and other fertility treatments, ICSI has slightly more risks. The main risk being to the egg, which may be damaged when they are cleaned and injected with sperm.

From a patient’s point of view, ICSI is much the same as IVF – it is what happens in the laboratory that differs. With IVF, the eggs are put in a petri dish together with several thousand prepared sperm, then left overnight for fertilisation to hopefully occur. With ICSI, each mature egg is injected directly with a single sperm under a high-powered microscope.

Whether IVF or ICSI is used, eggs are incubated in the laboratory overnight and examined the following day for signs of fertilisation.

ICSI is a delicate and precise technique that requires the use of specialist micromanipulation equipment by highly skilled practitioners.

ICSI can only be performed on mature eggs. Usually, we expect about 75% of eggs to be mature.

ICSI maximises the chances of fertilisation where there is known to be an issue with sperm quality or quantity. Over 90% of couples having IVF treatment with ICSI will achieve fertilisation of some of their eggs. Fertilisation cannot be absolutely guaranteed because numerous factors affect this, including egg number and quality.

The embryologists choose the sperm that are the most motile (best swimmers) and which look the most normal shape.

The injection technique may sometimes damage individual eggs. The overall damage rate is low (below 5% of eggs injected) but may be higher for individual patients, depending on egg quality.