There has been much debate in the media as to whether parents should sleep with or seperately from their parents. Developmental researchers and paediatric professionals are divided on the issue leaving many new parents confused about the potential risks and benefits of different sleeping arrangements. A study of 70 mothers and children in the U.S. compared those who always slept together, those who never slept together and those who were inconsistent. The researchers found that those mothers who were consistent with their children (either always sleeping together or always sleeping apart) were characterized by more positive infant and maternal behaviour and a higher quality of interaction at 9 months. A greater amount of sleeping together per week was associated with an increased duration of breastfeeding, mothers working fewer hours, less infant temperamental intensity and less maternal depression.
Taylor, Nicole, Donovan, Wilberta and Leavitt, Lewis - Consistency in infant sleeping arrangements and mother-infant interaction Infant Mental Health Journal 2008, 29(2), 77-94