ICSI versus IVF fertilisation rates

[Karbea]

Hello,

Doing some urghhhh!!! research, so that I can show DH when he gets home!
Does anyone know what the stats are for fertilisation rates for IVF and those for ICSI?
I guess for natural fertilisation it's about 20/25% isn't it???

Thank you!

I don't know about ICSI, but having recently been through a round of IVF, the clinic told me they expect around a 70% fertilisation rate. Not sure if that's useful for you.

Obviously, there's then a daily attrition rate. 20 - 25% sounds right for the number that would make it through to blast stage if going for a five day transfer.

Hi - it depends on a lot of things - we quote a normal fertilisation rate of about 60% for all eggs exposed to sperm, but when you have ICSI not all of the eggs may be injected. For example, an average result would be:
10 eggs collected, all mixed with sperm for IVF,expect 6 to fertilise
10 eggs collected, prepared for ICSI, 8/9 suitable for injection, 4/5 fertilise.
All clinics will give you their own average results based on their experience and your own history and test results

IVF assumes normal sperm parameters, the fert rate is much lower if the sperm falls outside the normal range, and there is a high risk of no fertilisation - hence we would do ICSI if we felt the sperm were suboptimal, but not routinely as you generally get fewer embryos.

Fertilisation rate naturally is not clear but it is estimated 10% of natural ovulations lead to a viable pregnancy.

HTH