I don't know how natural is defined, but I was induced at 41 weeks (LO just wasn't coming out on his own and placenta was starting to fail), laboured in the water a bit and had a pain killing injection in my hip (not sure what it was, but it was gooood, and it gave me a bit of a rest), then got an episiotomy at the last minute just before LO came out. All in all it was 8 hours, all of it back labour, and the last pushing stages I was on my side.
I never really wanted an epidural, despite the pain, as I thought it would delay things and just wanted bubba out ASAP. It's not a foregone conclusion, so don't feel pressurised if you don't want it. Like another poster said, the pain is a means to an end and will stop when the baby comes out (or a few hours later, they don't tell you about the contractions you get when your cervix closes!).