Day 3 embryo
Also written as cleavage-stage embryo
An embryo three days after fertilisation, typically consisting of six to ten cells.
In plain English
It's an embryo three days after fertilisation, an earlier stage than a blastocyst.
Why it matters
Some clinics transfer at day 3 rather than waiting to day 5, depending on how many embryos are developing and clinic policy.
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.