Not yet born (2,5)
I believe the answer is:
in utero
'not yet born' is the definition.
(I've seen this in another clue)
This is the entire clue.
(Other definitions for in utero that I've seen before include "Where the foetus is" , "Pre-natal position (Latin)" , "Embryonic" , "Within the womb - routine (anag)" , "awaiting delivery" .)