During birth

I know they put an IV in your arm during birth, do you get to choose which arm? I'm asking because I cant handle needs in my right hand/arm. I don't know why, it just hurts and it swells up, and i panic. But the left is perfectly fine. I think its because all my life it was always on one arm. Thats a stupid question I know and i know i probably wont care because i'll be in so much pain but figured id ask