Sleeping positions

Ok I know it doesn't matter the sleeping positions in the first trimester because the baby is so small however they say to start sleeping on your left side during second and third trimester because of the reduced blood flow to the baby while sleeping on the right side.  so since we're a little fluffy to begin with does this affect the baby early on in the first trimester. Has any of your docs said anything to you or has anyone asked? Perhaps a dumb question but I had to ask. I'm being anonymous because no one knows I'm pregnant yet and I'd like to keep it that way for a while :) thank you! 
Also for my fluffy gals which position is most comfy for you?