Expecting Portugal to introduce ruling (8)
I believe the answer is:
'expecting' is the definition.
(expecting can mean expecting a child)
'portugal to introduce ruling' is the wordplay.
'portugal' becomes 'p' (common abbreviation eg on car number plates).
'to introduce' is a charade indicator (letters next to each other).
'ruling' becomes 'regnant' (as in a queen regnant, a queen who rules by birth).
(Other definitions for pregnant that I've seen before include "Expecting a baby" , "Gravid" , "loaded" , "Expecting a child" , "Carrying offspring in the womb" .)