Sleeping on stomach

HELP! My baby is literally waking up several times a night acting like she isn’t comfortable. She grunts and throws her body all over her bed. (It’s not gas). When I pick her up and lay her next to me, she goes to sleep and sleeps peacefully. She napped today and rolled onto her stomach and napped for the longest! I’m assuming she’s trying to push herself over onto her stomach in her sleep. That makes me nervous. Does anyone let their baby sleep on their stomach and if not, how can I make her comfortable enough to satisfy the urge?