Parents are being warned not to risk their babies' lives by sharing a bed with them while sleeping. Latest evidence released by the Foundation for the Study of Infant Deaths (FSID) shows bed sharing is implicated in about half of cot deaths. The risk is greatest if either parent smokes, has been drinking or is very tired. Even without these factors, the charity said that the safest place for a baby to sleep was its own cot. Dr Chris Wright, consultant perinatal pathologist at the Royal Victoria Infirmary, Newcastle, examined 15 cases of unexpected death in infants between 2008 and 2009 - seven were found in the parental bed and two had died on a sofa. In the London area between 2005 and 2008, 173 babies died suddenly and unexpectedly. And 85 of these infants were found dead after falling asleep in bed with an adult or on a sofa.