Since the beginning of 90's, there is an increasing incidence of deformational plagiocephaly (DP). Based upon observational studies, some authors proposed to provide parents with advices about positioning infants. We recently observed that early specific counselling about "unrestricted motility", as suggested by E. Pikler, during maternity stay, is able to significantly reduce the incidence of DP at 4 months of life. In agreement with recent studies we did not observe a relationship between sleeping position and the occurrence of DP. Flattened head at birth was not an independent risk factor for DP at four months, suggesting that it could be more efficient to provide "unrestricted motility advices" to all parents and not only to a supposed "at-risk" population. Finally the absence of "unrestricted motility", rather than supine position, could be implicated in the increasing incidence of deformational plagiocephaly.