Hi and welcome!
Congratulations on your precious little one on the way! What wonderful news! Welcome to Cathe's Mom's Board!
The pain you're feeling is probably from the ligaments that support your uterus. I experienced this fairly early on in this pregnancy ( I'm 31 weeks now. ), and was able to deal with it by getting one of those maternity support belts. It goes around your back and under your tummy so that your back and the belt support more of the increasing weight of the uterus, rather than those ligaments. Mine was $13 at the Motherhood Maternity store. I have been able to continue all of my regular impact so far ( knock on wood
) as long as I have the belt on. I've started wearing one most of the time anyway as of 2 weeks ago to help with low back pain I was having. I have been modifying some of the faster turns and eliminating tapes with a super fast tempo for about 3 weeks now. The impact itself, though, isn't a problem. I'm not doing BMax or CTX cardio, but can still do Rhythmic Step or any of Cathe's older workouts. I'm waiting on DVD for the Intensity series, so I can't comment on the do-ability of those.
I am still doing regular ab work with some modifications. I haven't moved to an incline because so far I haven't had any sign that it's a problem for me ( light headedness or shortness of breathe. ). My ab workouts last less time than most of the diagnostic tests and exams the doctor does with me on my back, so I don't think I'm doing any harm. If I DO have to move to an incline, I'll be using my aerobic step. I don't do reverse crunches because they very early on felt like they were "crowding" the baby. I substitute either the "dead bug" moves or slow bicycles. For planks I can no longer comfortably lift a leg while holding the moves, and often need to drop to my knees before Cathe is through with me. For "superman" work, I substitute the exercise where you're on all fours and extend the opposite arm and leg. Obviously I'm not looking for a 6 pack here, but I want strong abs to help push this baby out, and I want my muscles to remember where they came from.
I have some pregnancy videos, but am beginning to have hope that I won't actually need any of them except the yoga ones ( I never did yoga pre-preggo, so I'm sticking with pregnancy and beginner yoga workouts right now ).
Good luck! Keep in touch!
Erin and baby Rebecca ( 31 weeks and counting!! :-D )