I had a waterbirth with #1. In my experiences water has been great for relaxation and pain relief.
With #1, my contractions started regularly at 8mins apart, with no previous warning. After a few hours of dozing between contractions, I laboured at home in a spa bath until my contractions were about 5 min apart. The only thing that got me out was the midwife assuring me she there would be a bath ready when I got there.
I was in too much pain for them to check where I was at when I got to the hospy (the needed me to lie on my back, but I suspect bub was still posterior at that stage), so I got straight in the water....and back in my zone. Obviously it's labour so it's not entirely a comfortable thing, but in terms of keeping me feeling relaxed and warm it worked really well, which meant I was really focussed.
There were poles for me to hold on to, so the midwife encouraged me to roll over so I was sort of floating on my back. I didn't want to because I was so comfy on my knees, but I guess with them not knowing how far along I was, they want to be able to better see what's going on? There might have been another reason. At any rate, it was really comfy when I rolled over, so no probs there anyway. I gripped the poles during contractions (and was told to let go inbetween otherwise my arms would be like jelly the next day), made big tidal waves over everyone, and had bub in the bath 3 hours after we got to the hospital.
With #2 I just used a shower for pain relief and that was relaxing and helped me focus too.
I tore both times, but to be honest I didn't really hold back when it came to pushing, for me pushing meant labour almost over so I wasn't at my wisest there.
So yeah. Moral of my story is that I highly recommend water as pain relief. Not that I've tried anything else.

But if you don't like it, you can get out. If you find labour slows down, you can get out, wait to progress and hop back in. It's not like you're stuck there. xo
Bookmarks