As soon as my wee girl could roll over she slept on her tummy. This was from about 3.5 - 4 mths old.
Zoe has always had amazing head control. I do have to admit the first night I didn't sleep a wink but after that I was fine. She naturally turned her head from side to side and was fine.
I had Plunket not long after and spoke to my plunket nurse and she said at her age with the good head control it was fine.
I'm not a big believer in using a safety sleep thing (however don't begrudge anyone else for using one
) so not only does she mostly sleep on her tummy but she sleeps wherever she ends up in her cot
At the end of the day it is personal choice what you are comfortable with. You would be surprised just how many babies are tummy sleepers but because you hear about all the bad things and that you shouldn't let them people tend to keep it quiet.
I think its about being sensible and as long as there isn't anything else in the cot but a nice firm mattress it should be fine.
If you aren't comfortable try using a single sheet and wrap it around baby and tuck that in tightly or just really tuck the sheets in tight. Or a sleep sack and tuck the end into the end of the cot.
I have noticed as Zoe has gotten older she prefers to sleep on her side and now she can roll onto her back anyway if she wants to which occassionally she does.
However her most fav position is on her tummy with her knees drawn up under her bum in the air.............how that can be comfortable I really don't know!!!