Obstructive about a film excited Yankee's expecting (2,3,6,3)
I believe the answer is:
in the family way
'expecting' is the definition.
(both can mean pregnant)
'obstructive about a film excited yankee's' is the wordplay.
'obstructive' becomes 'in the way' (to obstruct someone is to get in their way).
'about' is an insertion indicator.
'excited' is an anagram indicator.
'yankee' becomes 'Y' (phonetic alphabet: alpha, bravo, charlie etc.).
'a'+'film'='afilm'
'afilm' anagrammed gives 'famil'.
'famil'+'y'='family'
'intheway' going around 'family' is 'IN THE FAMILY WAY'.
(Other definitions for in the family way that I've seen before include "Expecting" , "carrying child" , "pregnant" .)