Bedsharing with parents a risk for babies – experts respond

The risk of Sudden Infant Death Syndrome (cot death), is five times higher in babies who share parents’ beds, even when the parents are non-smokers and the mother has not been drinking alcohol and does not use illegal drugs, according to new research.

Solo sleeping safestThe study is the the largest of it kind and includes data from almost 1,500 SIDS cases across Europe, the UK, Australia and New Zealand.

In the article, published in BMJ Open, authors conclude: “88% of the deaths that occurred while bed sharing would probably not have occurred had the baby been placed on its back in a cot by the parents’ bed.”

The researchers do note that there is no risk from having an infant in bed for feeding or comfort provided the infant is returned to his or her own cot for sleep.

“SIDS remains a major cause of death among babies under one year of age in New Zealand and other high income countries,” said author Professor Ed Mitchell, from the University of Auckland in a media release.

“Parents need to know the risks from bed sharing, especially for babies under three months.

“Health professionals have a duty to inform them. Innovative strategies such as the wahakura and pepi-pod provide alternatives to bed sharing, and are attracting interest overseas.”

Our colleagues at the AusSMC collected the following expert commentary. Feel free to use these quotes in your reporting. If you would like to contact a New Zealand expert, please contact the SMC (04 499 5476;

Professor Paul Goldwater, Senior Consultant, Microbiology & Infectious Diseases at SA Pathology (North Adelaide) and University of Adelaide School of Paediatrics and Reproductive Health

“The paper’s authors are well known to me (two are co-investigators with me on an international SIDS study) and have experience with large studies on the epidemiology of SIDS.

“Their findings are not surprising and confirm that co-sleeping is particularly dangerous for babies under three months of age. The main message is that co-sleeping (with or without other risk factors such as alcohol, other drugs or smoking) should never occur, but it is OK to breast feed in the parental bed and then to put the baby to sleep “face up” in its own cot (with clean linen) in the same room as the parent(s).

“The study pre-supposes that accidental smothering is the reason for these deaths while providing no autopsy evidence to that effect. The paper does not discuss the role of bacterial infection and only briefly alludes to it peripherally in terms of thermal stress (overheating) and the release of lethal toxins. In my view, it is likely that the theory of respiratory compromise due to smothering accounts for only a very small minority of cases.

“Many people will ask why the parental bed or sofa represents a dangerous sleeping surface; both of these are heavily contaminated with bacteria such as E. coli and Staphylococcus aureus, which are equipped with a variety of lethal toxins. A baby sleeping in such a contaminated environment could inhale or ingest shed skin cells covered in these bacteria. A genetically susceptible baby is at risk in the co-sleeping situation. This risk is further increased with every additional risk factor.”

Dr Mark Kohler, Lecturer at the Centre for Sleep Research, University of South Australia, comments:

“The opinion as to why bed sharing is a risk factor for SIDS is largely based on the likelihood of smothering the infant in some way and increased exposure to toxins. This thinking is highlighted by UK and Australian recommendations that types of parents place infants at greater risk than others – for example, those who smoke, are intoxicated, or take drugs/medication that alter awareness, cognitive ability and/or consciousness.

“The finding by Professor Carpenter and colleagues, which are hard to deny given this is the largest study of its kind, that bed sharing with any parent increases the risk of SIDS fivefold shows us that there are still important factors in our understanding of SIDS that have been missed. These may include overheating, exposure to pathogens in the bedclothes, changes in the child’s arousal response, amongst others.

“Similarly, the fact is that when adults are asleep their awareness and state of consciousness is altered, irrespective of whether drugs or alcohol have been taken. One important consideration of the study methods is that it does not answer the question as to why parents were bed sharing with their infant to begin with. Someone might say “always trust a mother’s intuition”, and while that someone is usually the mother, it begs the question as to why there was a felt need to bed share initially. Perhaps there was something about the infant the parent was sensing that if explored can help explain the true “type” of parent (and infant) at greatest risk.

“Combined, current bed sharing practises, particularly in western culture, still appear to place children at risk of SIDS and research should continue to provide greater understanding of why in order to avoid the devastating consequences.”