Hi there and congratulations!
I would not do it unless you check with your doctor first if you were thinking of doing it while you are pregnant. It is a very intense workout. My husband has done the P90X off and on for a couple of years now. He got my son doing some of the exercises as well, especially during baseball season to work up his core muscles. They do have several people on there showing you different ways to do the excercises based on how hard or easy you want to do it. However, seeing some of those excercises and how long you have to do them, most are an hour, I'd still check with your doctor first. Now after the baby, if you can find the time, it would really get you back in shape! Like the previous moms said, it will literally kick your butt and you will not be able to move that first week! My husband said that he couldn't believe the muscles that were so sore! But if you stick with it, you WILL see results! Oh and you only need a couple of weights, a chair, maybe a mat if you want one, and maybe some of those resistance bands if you don't have a place for some of the pull ups.
Good luck with the baby and the work outs!