Thanks so much for your replies everyone. It's so great to read other peoples stories. Especially when I was feeling like i was the only overweight woman on the planet considering getting pregnant and feeling like I would be condemned by the medical profession for doing so.

With my first PG, like Marydean the only time I was weighed was just before I went into theatre for my CS. And it was nice that my OB didn't focus on my weight. Mind you pre preg last time I was 17 kilo's lighter than I am now.
And like Briggsy;'s girl I did get PE late in my last pg (from 35 weeks onwards) but it was classed as moderate and I'm confident weight did not play a part in it as I have always had normal BP at any other time.
I think if I do happen to fall preg at this size I will focus on eating healthily and walking lots so that hopefully I gain minimal pregnancy weight.

thanks again for all the replies