Blastocyst grading
A system embryologists use to describe a blastocyst's expansion stage and the quality of its two main cell groups, usually written as a number and two letters.
In plain English
It's a shorthand code, like 4AA, that describes how well developed and how tidy-looking the cells in your embryo are.
Why it matters
Grading helps embryologists choose which embryo to transfer first, though grade alone doesn't guarantee whether an embryo will implant.
Related terms
Guides that cover this
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