When I was PG with DD2, I had PSD. (How many acronymns can I use in a single sentence?) I had to be very careful about exercising-- any single-leg weight -bearing activity was painful, and squatting and opening up the hips really aggravated it. Right now I'm trying to do what I can, but on days I do barre workouts I already have a dull ache in my pelvis. I've been doing the Long and Lean pregnancy workout DVD which is similar to barre, but more gentle. Walking makes it worse, so I think I'll join the Y this fall and swim through this pregnancy.
I've had very different workouts with each baby. With DD1, I was doing triathlons before I got PG, so I just kept on swimming and running as much as felt good. I stopped cycling because I am klutzy. With my second, I ran 4 miles a day about 3-4 days a week, plus weight lifting. After the first trimester, that was painful so I embarassed myself at Zumba twice a week. I have to remind myself that I'm getting older, my body is changing, my life circumstances are different. It is best to do what I am able and what I enjoy at the time.