Insufferable! Can't have children? (10)
I believe the answer is:
unbearable
'insufferable' is the definition.
(thesaurus)
'can't have children?' is the wordplay.
I cannot quite see how this works, but
'have' could be 'bear' (synonyms) and 'bear' is found within the answer.
The remaining letters 'unable' is a valid word which might be clued in a way I don't see.
This may be the basis of the clue (or it may be nonsense).
Can you help me to learn more?
(Other definitions for unbearable that I've seen before include "Insupportable" , "Intolerable" , "it's just too much!" .)