Dr. David Katz at the University of Colorado reviewed 393000 births between 2007-2012. Of these 80% live between 3000-6000 ft. Only 1.9% live over 8000 ft. Death rates from Sudden Infant Death Syndrome state-wide was 4.2 per 10,000 but over 8000 ft the rate was 7.9/10000.

it is possible that hypoxia is a contributing factor, but there is no research on this. Meanwhile parents are urged to place their babies on their backs to sleep and remove all soft material from the sleep area.