This is my experience.
My second birth was drug free and it was sooooo much better.
The drugs I was given for my first birth (bee stings and gas) did nothing to reduce the pain and just made me feel worse, so the second time I said no I don't want any drugs. I had a consious birth (like the Marley's consious party ha ha!!!)
You need your wits about you and all the strength you can muster. Mind numbing or pain relief drugs they give you and most of the interventions like epidurals, gas, bee stings etc hinder rather than assist your ability to give birth.
I'm not saying it wasn't painful, but I am saying I could deal with the pain better without drugs.
I found it good to have an attitude like - Don't avoid the pain, embrace the pain of birth - bring it on !!!
My yoga baby/midwife says it's not a pain - it's a sensation. But whatever you call it you'll be able to deal with it better without mind-numbing pain killers.
Also don't be worried about annoying everyone else during labour/birth. You'll be in pain, you might need to yell, scream, do breathing etc, but don't let that be a reason to have staff sedate you.