The risk of sids
is definitely increased in babies who sleep
on their tummies, and slightly less if sleeping on their side.
If baby falls asleep on her tummy, try to turn her over to her back once she is asleep. Make sure her bed doesn't have any pillows, quilts, or other soft bedding in which she could suffocate, in case she falls asleep on her stomach and you don't have a chance to turn her.