supplement w/ weight training
I know its hard to cut back using weights when you are so used to it but congratulate yourself on taking the first step to doing away with them. You are exactly right, stepping with weights does take its toll on your body. It is unnecessarily stressful on the joints, especially so when pregnant. I must say that I'm astonished that you were able to do this through your pregnancy uninjured.
I recommend that you keep your five day workout plan. But instead of stepping with the weights, save the weights for after your cardio training. By incorporating a weight training program, you will shock your muscles, boost your metabolism, and redefine your physique. For your weight training, you can do one or two body parts after your cardio training. The goal is to hit each major muscle group atleast once(or even twice)a week. Target your legs, back, chest, shoulders, biceps, and triceps.
No, I decided not to make a pregnancy video(at least for now). I wanted to experience all of the stages of pregnacy and postpartum before designing a workout to meet those needs.
My workout plan during pregnancy was to keep doing everything I was doing prior to getting pregnant however modifying as I went along. My goal was to maintain my current level of fitness, not improve it. I taught my 6 cardio classes weekly but dropped down to 4 and eliminated kickboxing (due to joint stress) by the last trimester. For weight training, at the four month mark I avoided traditional crunches, converted all of my weight work that was flat on my back to an incline position, and only lifted about 75% of my maximum strength, dropping to 50% by the last month.
Good luck and please, please, please, take off those weights while stepping. Good Luck!