DH and I have been invited to a formal event where the dress code is 'smart' but I also have to dress for the weather and walking on uneven ground. I have a large bump. 
I already have this dress:
www.isabellaoliver.com/maternity-clothes/uk/100/sale/maternity-dresses/DR051.html
Would that be suitable if I dress it up with a pashmina or jacket? although I only have a Gap blazer and I suspect that is too casual. I don't mind buying a jacket/wrap if it's not too expensive.
Also, what shoes do I wear? Would mid height heels be OK?