Hi, I have Pos as well, I had an Ob for falling pregnant but went public after a few not very nice private hospital stories scared us off of our closest private hospital! The most important thing is to find someone your wife feels comfortable with, most Ob will specialise in Pos as it's so popular these days. Congratulations on the I know it can be a struggle to fall pregnant, and it is truely wonderful news!
My care was done through a birthing unit run by midwifes, they were not concerned with the Pos part and after both births i went back to the Ob for a check up!
Wishing you the best of luck in finding your birthing solution!
Snoopea