Definitions of Terms Used on This Site
Co-sleeping and Bed-sharing
When discussing parent-infant sleep location it is important to clarify terminology and definitions, as the terms 'co-sleeping' and bed-sharing' are often used interchangeably by the public, by practitioners and sometimes in the research literature. They each have quite specific meanings, however:
Among the anthropological and epidemiological research literature (which includes the majority of SIDS-risk case-control studies and parent-infant sleep studies) the term 'bed-sharing' is used to mean 'adults and infants sharing the same surface for sleep'. In some studies sofa-sharing and other same-surface sleeping arrangements are subsumed into bed-sharing. Technically bed-sharing means sleeping for at least some of the night in the same bed as a parent or parents.
Among researchers, 'co-sleeping' is used to mean parents and infants sleeping in close proximity, but not necessarily on the same surface. Room-sharing with the infant's cot beside or near the bed and parents and infants sleeping on adjacent mattresses could be included in co-sleeping. Bed-sharing therefore is a sub-set of co-sleeping, but not all co-sleeping is bed-sharing.
Among health practitioners a different set of meanings are commonly used. Bed-sharing sometimes means 'bringing a baby in to bed for a feed while the mother/caregiver is awake', while co-sleeping refers to 'sleeping in bed with a baby'.