Being pregnant in med school was not so bad, but I had a really easy pregnancy. Being the parent of a newborn infant in med school was an entirely different matter, let's just say I'm pretty happy I passed my last class.
I was not the only one pregnant in my class, it happens every year at every school. If you have the option to plan ahead, sit down and talk with your administration so that any arrangements for your health, education, and comfort can be made in advance. That way it is just one less thing to worry about.
Just as an aside, having weekly OMT lab was a great help for all of the aches and pains that came along with pregnancy.
Hope this all helps.