I was going to say brown muslin but I don't think it would go right with your complextions and hair...in that case I'm voting for white canopy. I like the black one too but I don't know if that would be too dark for your preferences.
As for the clothes...ummm that's really not my department, lol. You might want to google "pregnancy portrait gallery" or "maternity portrait portfolio" or something along those lines, and use the outfits of the women in the galleries to give you ideas.
As for the clothes...ummm that's really not my department, lol. You might want to google "pregnancy portrait gallery" or "maternity portrait portfolio" or something along those lines, and use the outfits of the women in the galleries to give you ideas.