I have a friend-of-a-friend who recently underwent a brutal, brutal labor. Two failed epidurals and a fourth degree tear, to sum it up. Having gone through my own natural labor, I know how hard it is when you ARE prepared. I can't imagine the pain and confusion and sense of betrayal of someone who A) isn't physically or psychologically prepared and B) is stuck in the medical model of lay on your back and don't move or you will disrupt the fetal monitor.
Anyway, the update is that apparently, she is still angry about it. I would be! She was informed, after the fact, that up to 10% of epidurals simply don't take. They only work partially or not at all, or perhaps they wear off just when you need them most.
I don't know how accurate this percentage is. I doubt that there are even published statistics on it - and it probably varies by hospital. But that's what she was told, too late for her. I kind of want to cry just thinking about it. I had a first degree tear and that was painful enough. It took me 6 weeks of limping around and pain pills to recover. I don't even want to think about what a fourth degree tear (after her episiotomy, of course) is like.
Here's hoping that all the ladies out there never have to go through such an ordeal.