Hi there,
I've just ventured into home yoga practice myself, and the same thing was bothering me.
I've checked out a few sites that I've used for home yoga tutorials, and in getting started with my home yoga experience, and it seems that yoga in general is safe while pregnant, but that there are poses you'll want to avoid!
I would suggest looking for a book on yoga while pregnant, or maybe getting a home yoga instructor or even a home yoga DVD for pregnant women, to play it safe?