Can you explain a little more what you mean? Do you mean like twisting your torso side to side while laying down? That would be fine. I don't see why that would concern you unless you're throwing yourself torso from side to side with a lot of force.
Just be careful to not twist your body too much when you do. If I start to twist and feel any sort of stretching or strain in my stomach area I stop. My chiropractor still does that move to me but doesn't force it right now because I'm pregnant. Just be careful with it.
I highly recommend seeing a chiropractor. Pre pregnancy with DS I cracked my back like this religiously and then it just didn't help me while pregnant. My chiro did a very similar move on me every week or two but the impact was so different!
Re: Cracking your back
Do you mean like twisting your torso side to side while laying down?
That would be fine. I don't see why that would concern you unless you're throwing yourself torso from side to side with a lot of force.
DS2 due 12/12/18