At the moment parents are told they should not share their bed only if they have been drinking alcohol, taking drugs or if they smoke.

It is estimated that around 120 babies' lives could be saved in the UK every year.

The new study found that breastfed babies under the age of three months who sleep in their parents' beds face a five-fold increased risk of cot death.

The research, led by researchers from the London School of Hygiene and Tropical Medicine, examined data from five studies on cot death, also known as sudden infant death syndrome.

The authors found that the risk of cot death among breastfed babies under three months increased with bed sharing, even when the parents did not smoke and the mother had not consumed alcohol or drugs.

Research

The research, published in the BMJ Open, found that 22% of the cot death cases occurred when babies were sharing a bed with their parents. The authors estimate that 88% of such cot death cases would not have happened if bed sharing had been avoided.

The risk associated with bed sharing decreases as babies get older but if either parent was a smoker or the mother had drunk alcohol or used illegal drugs at any time since the child was born, the risk was greatly increased.

Awareness

Lead author of the study, Professor Bob Carpenter, from the London School of Hygiene and Tropical Medicine, said: "If parents were made aware of the risks of sleeping with their baby, and room sharing was instead promoted in the same way that the 'Back to Sleep' campaign was promoted 20 years ago to advise parents to place their newborn infants to sleep on their backs, we could achieve a substantial reduction in cot death rates in the UK."

Francine Bates, of The Lullaby Trust, a charity which promotes safe sleeping in babies, said: "Our core message remains that the safest place for a baby to sleep for the first six months is in a crib or cot in the same room as a parent or carer."