I know you want a totally natural birth I have had one my son the second one. But my first my daughter, I was late and my pushing pooped out (after 18 hours it does) she was stuck (very large head) They gave me the pitocin please as for some thing to take the edge off. When it starts to work you will want to have a touch of something. I had just enough that it didn't make me sleepy or any thing but it did allow me to focus on my breathing and pushing. Good luck girl. It is an amazing experance, just when you thing it's not that wonderful little person arrives and you just can't explain the joy and emotions you feel.
Praying for you all.
Grandma"s must be going nuts waiting huh?