Controlled blood sugar but excessive thirst... any advice?

[lovechristmas]

Hello,
A quick question I am posting here and in the pregnancy thread.

I have gestational diabetes and since my GTT at 20 weeks I have had excessive thirst. I was on metformin and now jut injecting with insulin.

I am now 38 wks pregnant and still experiencing such a dry mouth and wake desperate for a drink almost every hour through the night. I drink litres and litres, far more than what is considered safe but feel better than if I try to deprive myself. The consultants I see with regards to my GD at hosp didn't seem bothered then at an appointment a few weeks ago it was as though they actually read my food/fluid diary for the first time (either that or listened) and became worried. They discussed water deprivation testing and all sorts as I should be having seizures with the amount of fluid I drink!

I honestly feel OK about the volume - my test results were OK, just significantly diluted samples lol! I crunch ice alongside drinking to try to help and of course only drink sugar free fluids. Has anyone else ever experienced this or have any advice - would love more than an hours sleep at a time to help get me through a labour!