Waterproof coat

[Kopparbergkate]

Ive asked this in Chat and Style and Beauty but no joy I'm looking for a warm (ish - I know I'll feel hotter as I get bigger) waterproof maternity coat for the winter.

I've seen the Mamalicious ones, the Jo Jo parka, the H+M parka etc but, having asked the stockists, none of these are rain proof apparently (!). Obviously the smart wool coats in IO etc aren't either.

I'm looking for a school run/dog walking coat (at least mid-thigh) that will keep me and bump warm and, most importantly, dry if the weather carries on like the summer/autumn have been so far. I like the Merrell Wakefield but i don't think that will accommodate a bump and I'm not due until early April so this coat will probably have to see me right through. Any ideas?

The brilliant waterproof I have is currently getting v snug around the chest...