I wasn't told to drink lots (or any!) water during my labour that I can remember. Or to give a pee sample.

I do remember having to wee and getting helped from the bed to the loo at least twice (where I think I almost fell asleep too!), and giving myself the WORST bruising on the inside of my arm/elbow from holding on so hard to the rail next to the toilet during contractions I guess (the bruising lasted several months!). Anyway, nothing came, and it was apparently how the baby had moved, so they gave me a catheter for just a few minutes, and I remember feeling so much better afterwards. I didn't have an epi.

I guess just go (or try to) when you feel like you need to, and if you can't, then get a catheter. And I would only drink when I wanted to. Not sure I really answered your questions there.