Closes up damaged uterus following section (7)
I believe the answer is:
sutures
'closes up' is the definition.
(stitches up with sutures)
'damaged uterus following section' is the wordplay.
'damaged' indicates an anagram.
'following' means one lot of letters go next to another.
'section' becomes 's' (legal abbreviation).
'uterus' anagrammed gives 'suture'.
'suture'+'s'='SUTURES'
(Other definitions for sutures that I've seen before include "Surgeons' stitching" , "Stitches for wounds" , "Surgical stitches" .)