pls help! my boyfriend farts while he sleeps, is this normal?

my boyfriend farts while he sleeps, is this normal? at first i thought that it was my imagination, but then after a while i was sure. because i fall asleep later than him, i stayed up late and waited... and then it begun, and he does this every night! what can i do? take him to see a doctor? or maybe sleep in another room? this situation strangles our relationship and since then i have nightmares... thanks for your help