ABSTRACT. Eighty to ninety per cent of primiparous and multiparous women held their newborn infants to the left of the body midline. Left side preference was independent of handedness and was typical also of non-pregnant female—but not male—students and may therefore be a genetically determined human, female behaviour. Right-holding, occurring in 10 to 20% of non-separated women, was observed in 30 to 40% when mother and infant had been separated for about 24 hours. This observation may be of general interest, suggesting that perinatal maternal anxiety and uncertainty can alter a pre-existing behaviour. The right-holding, non-separated mothers differed from left-holding ones in a number of ways: they held their babies with less body contact, they perceived a delay in accepting the foetus or newborn as their own, and—when checked 3 years after delivery—they had had a more frequent contact with the Child Health Center during this time. Right-holding may in some mothers be an early sign of a disturbed mother-infant relationship. It may indicate either an insensitivity of the mother to the signals of the infant or that the infants signals are inappropriate. Carrying differed somewhat from holding. In addition to right and left preference a third modality—“in hands”—was observed. Immediate post partum naked skin-to-skin and suckling contact between mother and infant eliminated the “carrying-in-hands” behaviour. This observation adds to others showing that experiences during the immediate postnatal period may mould the maternal behaviour pattern.