Fertilisation rate
The proportion of mature eggs that successfully fertilise after insemination or ICSI.
In plain English
It's the percentage of your collected eggs that actually fertilise on day one after egg collection.
Why it matters
Your clinic will call the morning after egg collection to tell you this number, which starts to shape how many embryos you'll have to work with.
Related terms
Guides that cover this
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.