New research published in the journal BMJ Open says that sharing a bead with a newborn baby heightens the risk of cot death significantly.

Even in babies who had no other risk factors for sudden infant death syndrome (SIDS) apart from sharing their bed with parents, 81% of the deaths in infants under the age of 3 months could have been prevented by avoiding bed sharing, the analysis said.
Currently, the US and the Netherlands recommend that parents should not share a bed with babies for the first three months of their lives, but in the UK, it is recommended that parents decide on sharing a bed with their babies.
Source-Medindia