If you feel comfortable laying on your stomach then you can :) You'll start feeling uncomfortable long before it can do anything to your LO. Theres days where im on my phone & happen to roll over on my belly.. it isnt uncomfortable yet but i still only do it for a limited amount of time. I'm a chicken 🙈 lol your back starts to get uncomfortable & isnt the best for your baby. Left side is best & beneficial, try to lay on your right too tho as often as you can so baby doesnt get "embedded" into strictly your left side.

My doctors exact words when I was pregnant . "As long as you're comfortable, lay on your tummy until the day you give birth. The only bad position to lay in is on your back.".