tetiana - I would not ask what the doula's birth plan is; really, if they have an answer you know they are not a very good doula! It is YOUR birth plan that matters. Period.
The above questions are all good ones. I would add "what is the best birth you attended" as well as "what was the hardest birth you attended". Also to be more specific, what was the hardest complications you have aver dealt with in birth.
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