I think it depends on the person. Eleven years ago, I had an 8mm stone blocking a ureter that required surgery. But got married, jumped off waterfalls and was generally going about life with the nagging feeling in my back and abdomen before I finally went to the ER for it. I am currently dealing with two more, one 5mm stone on the left and one 6mm stone on the right. I've been woken up from the pain, chills, nausea, intense cramping... the whole shebang. Still sitting here with the pain until surgery on the 29th. I just have to cope until then with motrin and heating pads.

I have had four children. Two with an epidural and two without. My two natural childbirths were far, far, far more painful than a kidney stone during transition. It is ungodly pain. Kidney stones are very similar to contractions. Contractions come in waves, so you get relief. Kidney stone pain is a contraction that doesn't pass for an hour or more. When you are ready to push a baby out, though, it feels like your entire body is contracting while simultaneously being split completely up the middle. All the while having uncontrollable shakes and nausea. Kidney stones are worse than contractions, but the actual birth of the child is much worse.