Around 120 baby deaths could be prevented in the UK every year if parents stopped sharing beds with their children, research has suggested.
A 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.
Researchers estimate that 40% of the 300 cot death cases which occur in the UK each year could be prevented if parents only brought children into their beds for comfort and feeding, but not sleeping.
At present, NHS officials only advise that parents should not bed share if they have been drinking alcohol, taking drugs or if they smoke. But the authors of the latest study said that the guidance should be expanded to dissuade all bed sharing - especially with babies under three months.
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 examined the records of 1,472 cot death cases and 4,679 control cases. They found 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.
Babies who slept in their parents' beds had a five-fold increase of cot death compared with children who slept in a cot in the parents' room.
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 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.
"Currently in the UK more than half of cot deaths occur while a baby is sleeping in the same bed as its parents," said lead author of the study Professor Bob Carpenter from the London School of Hygiene and Tropical Medicine. "Although it is clear that smoking and drinking greatly increase the risk of cot death while bed sharing, our study shows there is in fact an increased risk for all babies under three months who bed share, even if their parents do not smoke or drink.
"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. Annually there are around 300 cot death cases in babies under a year old in the UK, and this advice could save the lives of up to 40% of those. Health professionals need to make a definite stand against all bed sharing, especially for babies under three months."
In light of the new study, officials at the Department of Health have asked the National Institute for Health and Care Excellence (Nice) to "urgently" review guidance on bed sharing. A Nice spokesman added: "We are reviewing our guidance on the care of women and babies after birth - including the advice on sudden infant death syndrome. Any death of a child is a tragedy and one that any parent and health professional would want to prevent. Sleeping alongside a baby increases the risks to the child - including death. We currently recommend that doctors, midwives and nurses should warn parents of the risks of sleeping alongside a baby in a bed. The safest place for a baby to sleep is in a cot in their parents' room for the first six months."