All four of my babies use to sleep on their bellies which we called then the prone position and was well recommended by doctors and grandmothers! Babies in this position tend to sleep more soundly, less arm-startled reflexes due to loud/sudden noises and sleeping on their tummies made me feel at ease from choking due to spit-ups and babies get less if not at all, colics as they pass gas more easily while sleeping in this position. Reason why I found it strange all of a sudden, upon reading it, if not ironic that it is blamed as a possible position to cause SIDS on babies! Two different people I know in the past, whose babies died of SIDS...the babies were sleeping on their backs, possibly overfed and milk residues were found in their nostrils...and I always use to say if only they were made to sleep in a prone position...sad.now my babies  (30 to 15 youngest) are all grown and all healthy!