Does ICSI hurt the egg?

The egg is handled with a very fine needle under controlled lab conditions. Not every injected egg will fertilise or develop normally, which is expected and monitored by the embryology team.

Is ICSI more likely to work than standard IVF?

Where there is a sperm-related fertility problem, ICSI usually gives a better fertilisation rate. Where there is no such problem, the evidence for an overall benefit is limited.

Can ICSI be used with frozen sperm or surgically retrieved sperm?

Yes, this is one of the common reasons ICSI is chosen, since it needs only a single usable sperm per mature egg.

Does ICSI increase the cost of a cycle a lot?

It adds a fee, but the amount varies by clinic. Ask for the exact figure in your treatment plan before you start.

Are babies born after ICSI different from those born after standard IVF?

This is a question for your clinic and for published research rather than something this page can answer with a figure. Ask your clinic what they can tell you based on current evidence.

ICSI: what it is and when it is used

Written by Zayn Miah & R KhanomLast updated 17 September 2026Not clinically reviewed

Short answer: ICSI, intracytoplasmic sperm injection, is a way of fertilising an egg by injecting a single sperm directly into it, rather than mixing eggs and sperm together and letting fertilisation happen on its own. It is most often used where there are sperm problems, but some clinics offer it more widely. Ask your clinic why it is being recommended in your case.

What happens during ICSI

After egg retrieval, an embryologist selects a single sperm and injects it directly into the centre of a mature egg using a very fine needle, under a microscope. This is done for each mature egg collected, one at a time.

The embryos are then cultured in the same way as with standard IVF, and monitored over the following days for signs of normal fertilisation and division.

How this differs from standard IVF fertilisation

In standard IVF, eggs and a prepared sample of sperm are placed together in a dish and fertilisation happens without direct intervention. ICSI bypasses several of the natural barriers sperm would otherwise need to get through, which is why it is used when those barriers are the problem.

When ICSI is typically recommended

Low sperm count, poor sperm movement, or a high proportion of abnormally shaped sperm on semen analysis
Sperm retrieved surgically, for example in cases of azoospermia
Previous cycles where fertilisation failed or was very low with standard IVF
Using frozen sperm where quality is a concern
Some cases involving PGT, where clinics want to reduce the risk of contamination from extra sperm around the embryo

Some clinics offer ICSI routinely rather than only where there is a sperm-related reason for it. The HFEA has noted that ICSI used without a male factor indication does not have strong evidence of improving outcomes over standard IVF in that situation, so it is worth asking directly why it is being suggested for you.

What it costs you

ICSI usually carries an additional fee on top of a standard IVF cycle, and it adds a small amount of extra time and handling in the lab on the day of egg collection. It does not change the timeline for scans, injections or the transfer itself.

What the evidence shows

ICSI reliably improves fertilisation rates where the sperm sample itself is the barrier to fertilisation. Where there is no male factor issue, evidence that it improves the chance of a baby compared with standard IVF is limited, according to HFEA's review of the evidence for this and similar add-ons.

Questions worth asking your clinic

Is ICSI being recommended because of a specific finding on my or my partner's semen analysis?
What fertilisation rate would you expect with standard IVF for our situation, compared with ICSI?
What is the additional cost for ICSI at this clinic?
If some eggs are immature, does that change whether ICSI can be used on them?

After fertilisation

Whether fertilisation happens by ICSI or standard IVF, the embryos are checked the next morning for signs of normal fertilisation, then followed over the following days to see how they develop.

Questions people ask next

Does ICSI hurt the egg?: The egg is handled with a very fine needle under controlled lab conditions. Not every injected egg will fertilise or develop normally, which is expected and monitored by the embryology team.
Is ICSI more likely to work than standard IVF?: Where there is a sperm-related fertility problem, ICSI usually gives a better fertilisation rate. Where there is no such problem, the evidence for an overall benefit is limited.
Can ICSI be used with frozen sperm or surgically retrieved sperm?: Yes, this is one of the common reasons ICSI is chosen, since it needs only a single usable sperm per mature egg.
Does ICSI increase the cost of a cycle a lot?: It adds a fee, but the amount varies by clinic. Ask for the exact figure in your treatment plan before you start.
Are babies born after ICSI different from those born after standard IVF?: This is a question for your clinic and for published research rather than something this page can answer with a figure. Ask your clinic what they can tell you based on current evidence.

Words on this page

Sources

IVF: what is IVF and how does it work?, HFEA (UK fertility regulator). Link checked 17 September 2026.
Treatment add-ons with limited evidence, HFEA. Link checked 17 September 2026.
IVF overview, NHS. Link checked 17 September 2026.

Written by patients, not clinicians. This page has not yet been reviewed by a named fertility professional, so it explains published guidance and points you to the original source instead of giving medical advice. It is not medical advice. Decisions about your treatment belong with your own clinic. Read our editorial policy and corrections policy.