My primary Doctor is male, but I typically see the female P.A. Doesn't phase me a bit either way, though.... When I was in Atlanta, I had a male Doctor as well... saw the same one for 8 years, and he was the BEST. His exam rooms had posters of beautiful golf courses on the ceiling over the exam tables, so you had something to look at, and he would keep you engaged in conversation throughout the entire exam, which made it go by so much faster (and made it almost unnoticeable).
What we have to bear in mind are, for the most part, they ARE professionals. They see so many of "those" per day, it's no longer a novelty, and I'm certain it neither phases nor arouses them after they've been doing it for a few years.