Content of little eggs yet to be delivered? (2,5)

I believe the answer is:

in utero

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'yet to be delivered?' is the definition.
(still in the womb)

'content of little eggs' is the wordplay.
'content of' means to look at the middle letters.
'little' becomes 'mini'.
'eggs' becomes 'utero' (I can't justify this - if you can you should believe this answer much more).
The centre of 'mini' is 'in'.
'in'+'utero'='IN UTERO'

Can you help me to learn more?

(Other definitions for in utero that I've seen before include "Within the womb - routine (anag)" , "being developed" , "Before birth (Latin)" , "Pre-natal position (Latin)" , "Before birth - routine (anag)" .)

I've seen this clue in The Times.

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