Meee! Not only was I unfit I am so incredibly UN-bendy! Also I'd tried yoga pre-pregnancy several times and pretty much always left crying because I was so rubbish at it and got really upset by the (imagined I'm sure) looks I got from the uber bendy people...
I've been going for 5 weeks now (I'm 22weeks pregnant - I think it's only recommended 12weeks+) and really enjoying it. We don't do anything that would give away fitness levels (or lack of), it's all breathing, pelvic floor exercises, lying down, relaxing, more relaxing, more breathing, ooh and some stretching! It probably varies btw classes but I wrote to the teacher before hand to warn her how crap I was, and she was really lovely. She assured me that previous yoga experience wasn't necessary.
Crucially, yoga really helps, I am able to relax and do exercises that really help with the (back, leg, neck) pain I am getting...
Also, I live in a very lefty yummy mummy type place but don't find those in my class judgy at all. They're really nice, though all talk is about pregnancy do's and don't's and I get bored easily...but that's a whole other story!
Good luck!x