IMSI (intracytoplasmic morphologically selected sperm injection)
A variation of ICSI that uses very high magnification to examine sperm shape in more detail before selecting one for injection.
In plain English
It's a more detailed version of ICSI where the embryologist looks at sperm under much higher magnification before picking one.
Why it matters
The HFEA rates this as an add-on with no evidence it improves live birth rates for most patients over standard ICSI.
Related terms
Guides that cover this
Sources
- Treatment add-ons with limited evidence, HFEA. Link checked 17 September 2026.
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