Conservative group overturning No 1 cut affecting mothers (1-7)

I believe the answer is:

c-section

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'cut affecting mothers' is the definition.
The definition and answer can be both acts as well as being singular nouns.
Perhaps there's an association between them I don't understand?

'conservative group overturning no 1' is the wordplay.
'conservative' becomes 'C' (UK political abbreviation).
'group' becomes 'sect' (I've seen this in other clues).
'overturning' says the letters should be written backwards.
'no s' becomes 'no i' (resembles No s).
'noi' in reverse letter order is 'ion'.
'c'+'sect'+'ion'='C-SECTION'

Can you help me to learn more?

I've seen this clue in The Times.

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