Since the Back to Sleep campaign promoting supine infant sleep position (face up), the incidence of SIDS has declined by more than 50%. However babies’ soft heads suffer from constant high pressure spots when they sleep on their back in one position which can result in a flattening of the skull over time. Plagiocephaly is the term that is used to describe a diagonal asymmetry across the head shape. More information can be found on Plagiocepahaly page.