Pain but only at night??

Ok, so my midwife wasnt really interested in offering help or explanation so thought I would ask everyone on here as this is where I get most of my advice from!! I am 31 weeks pregnant and am feeling great. I go all day without any pains or twinges and am fine when I go to bed. However every morning I wake up at 1am with the most excrutiating back pain and I just cant get back to sleep it hurts so much. I am sat at my desk yawning as I just cant sleep when I'm in so much pain so end up having to get up and go downstairs. Any body have any thoughts or ideas why this only happens at this time in the night? I have tried sleeping in my side, front, back and nothing helps!

get a pregnancy pillow and put between your knees - it must be your position in bed when you sleep

I suffer from pain in my back at night which is not that frequent and is caused by gallstones. You should read up about them, its quite common to get them during pregnancy and talk to your doctor if you think you have them.