I share the same concerns as you. Throughout the night, I found it hard to just sleep on the side. So I find myself on my back sometimes. But you will most likely feel a bit of aching and discomfort and switch again. Read that downside to sleeping on back for the little one is that there will be decrease in blood flow.
When you're pregnant you mean? You'll wake up right after because it feels uncomfortable. It won't lead to any complications
I actually do to lie on my back until about 3rd tri. wake up after awhile due to backache
It is found to have increased risk of stillborn
You will not lie on your back for long as it's uncomfortable.