Intracytoplasmic sperm injection (ICSI treatment)

What is ICSI treatment?

Intracytoplasmic sperm injection (ICSI) is a laboratory procedure carried out during IVF treatment where an individual sperm is injected directly into an egg. This can help to achieve fertilisation during standard IVF treatment if there is a problem with sperm quality or quantity.

When Simon Fishel and his team pioneered ICSI in the UK in 1990 it revolutionised IVF treatment for couples who have male factor infertility

Could ICSI treatment be right for me?

ICSI can help to overcome certain male fertility problems including:

  • When sperm are unable to penetrate or fertilise an egg
  • Low sperm count or poor sperm quality
  • A blockage or anatomical abnormality that prevents a man from producing/ejaculating sperm (for example after a vasectomy). In such cases sperm can normally be obtained using a minor procedure called surgical sperm retrieval


When is ICSI recommended?

  • If the quantity or quality of your sperm is unsuitable for conventional IVF treatment
  • When your sperm has been collected surgically
  • If you’ve had low or no fertilisation with IVF treatment previously
  • If the egg(s) you’re using were previously frozen.

Occasionally your consultant may still recommend ICSI with IVF, even if there don’t appear to be any issues with your sperm. ICSI has been shown to help improve success rates for couples that have not been successful with IVF in previous cycles.

What does the ICSI procedure involve?

During the ICSI procedure we inject a single sperm directly into the centre of an egg. After a few days of development and observation in the lab, we then place the embryo in the womb in exactly the same way as with IVF treatment.

My ICSI video

The video shows the process of Intra-cytoplasmic Sperm Injection (ICSI).  The egg is held in place while a single sperm is injected into the cytoplasm of the egg using a fine needle.

What are the success rates with ICSI treatment?

Fertilisation rates are slightly higher with ICSI compared to IVF because it virtually guarantees that the sperm penetrates the egg. There is no significant difference in pregnancy rates between IVF and ICSI. For more information on the success rates of ICSI treatment, you can see our individual clinic success rates for further information.

What does ICSI treatment cost

There is an additional cost for ICSI cost on top of the cost of IVF treatment. The average UK cost for ICSI is between £1,145–£1,325.

Please see our individual price lists for your chosen CARE clinic.

IVF treatments
Prices are indicative only but include monitoring, egg collection, embryo culture and transfer. Prices do not include drugs or other optional costs - costs typically range from £500–£1,000.
IVF £3,450–£3,750
Elective freeze of embryos  (excluding transfer) £2,950–£3,700
Intracytoplasmic sperm injection (ICSI) £1,145–£1,325

Intracytoplasmic sperm injection (ICSI) FAQs


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. 

How does ICSI work?

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 permanently 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.

ICSI bypasses many of the processes normally associated with fertilisation, which means that a sperm could fertilise an egg that might not otherwise do so. The risk of miscarriage or a birth defect is slightly higher with ICSI than with IVF. It appears to increase in proportion to the severity of male infertility and it is thought this factor contributes most to any increased risk, rather than the actual ICSI technique itself.

There have been large multi-centre studies looking at the development of children born after ICSI compared to naturally conceived controls and the data has been very reassuring. According to The Practice Committee for the American Society of Reproductive Medicine, studies to date support the safety and efficacy of ICSI to treat various male factor conditions.

We will continue to monitor ongoing research into outcomes for ICSI children and will ensure that you are given up-to-date information regarding any potential risks before you commence any treatment. Counselling is available to help you.