K.W.
hello,
Here is a photographer you might be interested in.
She's not cheap, but, amazing stuff.
I never did any professional photographs when i was pregnant, and wish i did. (I have 4 children).
She's photographed my children - and has done amazing work.
I know I've seen some photographs of hers of pregnant women and I recall them being beautiful.
www.wancketstudios.com
http://www.wancketstudios.com/index.php
Good luck!