Unborn (2,5)
I believe the answer is:
in utero
'unborn' is the definition.
(I've seen this in another clue)
This is all the clue.
(Other definitions for in utero that I've seen before include "being developed" , "awaiting delivery" , "Pre-natal position (Latin)" , "Before birth (Latin)" , "Before birth - routine (anag)" .)