Sleeping on belly Everytime I place my baby in his crib he flips over to his belly, I kept flipping him to his back but…

Sleeping on belly

Everytime I place my baby in his crib he flips over to his belly, I kept flipping him to his back but he refused to sleep. So finally 2 days ago I just left him on his belly and he slept so much better. The problem is that it freaks me out! He sometimes puts his face straight down into the mattress so I spend all night starring at him breathing on the monitor. I know they say once a baby can roll back and forth on their own it's fine but I'm still nervous. Are you moms letting your babies sleep on their belly?