Prompted by a Lancet report, the press told parents that sleeping with a newborn raises its risk of cot death - when nothing could be further from the truth, says Ayala Ochert.
Parents who bring their baby to bed with them know the dangers.
As they are constantly reminded by well-meaning family and friends, their marriage will suffer and the baby will remain overly dependent and will refuse to leave the parental bed when it gets older. But, in January, headlines across the country warned of a much more serious danger.
According to The Lancet , babies under eight weeks who share their parents'
bed have a higher risk of cot death, even if their parents aren't smokers.
It was well known that bedsharing is risky if parents smoke, drink heavily or take drugs, but before this study, there was no evidence of a risk for babies of non-smoking parents. The Lancet study, which looked at 745 cases of cot death in 20 European countries, was said to be the biggest of its kind. As soon as it was published, the Foundation for the Study of Infant Deaths changed its advice, saying that no parent should bedshare in the first eight weeks of their baby's life. Yet, with all the hype surrounding The Lancet paper, the highly provisional nature of that particular finding was overlooked, even though several of the paper's co-authors disagreed with the FSID advice.
"In my opinion, there's not enough evidence to tell non-smoking parents not to bedshare," says Peter Blair, the Bristol University epidemiologist who supplied the English data for the study. More significantly, after reviewing the evidence, the Department of Health has reached the same conclusion - not including the controversial "eight-week" recommendation in its updated advice to parents.
Blair says The Lancet paper simply presented a "secondary analysis" of the data, a theoretical model that predicted a higher risk for babies under eight weeks who bedshare. The raw data itself, however, showed no such increased risk. "There hasn't been one study published yet that has shown a real risk among non-smokers," he concludes. Another "big flaw" of the study, adds Blair, is that alcohol consumption - a known risk factor when bedsharing - was not measured in all the countries included in the study.
The advice against bedsharing for non-smokers has dismayed those, such as anthropologist James McKenna, who have long argued the benefits of "co-sleeping". McKenna, who runs a mother-baby sleep lab at the University of Notre Dame in Indiana, says there is substantial evidence that co-sleeping is the normal, natural way that babies have slept since humans first evolved. He believes that under circumstances that most closely mimic those early conditions - a breastfeeding mother sleeping alongside her baby on a firm surface with minimal bedding - co-sleeping may even protect babies from cot death.
McKenna, a primatologist by training, explains that the evolution of bipedalism in our species created much narrower pelvises, with the result that human babies are born with just 25 per cent of their adult brain capacity at birth (compared with 45 per cent in our closest cousin, the chimpanzee). This, he says, makes human newborns the most neurologically immature and the most dependent of all primates. During the first three months of life, when the risk of cot death is highest, babies are not good at regulating their own breathing or body temperature.
Helen Ball, director of Durham University's Parent-Infant Sleep Laboratory, says: "We've ended up giving birth to these underdeveloped infants who haven't really finished gestating, and they need a period outside the uterus to finish gestating and be in constant contact with the care-giver during that period. The closer they are to a care-giver, the better the chance of having their breathing and body temperature regulated for them."
The cause of cot death is not known, but recent theories suggest that it stems from an "arousal deficiency". Some babies are unable to wake themselves when they stop breathing for one reason or another. Using infrared video cameras and sleep-monitoring equipment, McKenna and Ball observed hundreds of sleeping babies and parents. Both found that babies who slept with their mothers woke twice as frequently as those who slept alone. "It gives them a lot of practice of getting awake and breathing," McKenna says.
They also found that the sleep cycles of mothers and babies synchronise when they sleep next to each other. This pattern of dreaming, deep sleep, and waking together is even stronger when the mother breastfeeds her baby, and breastfeeding mothers appear to be much more sensitive to the noises and movements their baby makes during the night.
Yet early research into infant sleep, carried out in the 1950s, looked exclusively at babies who slept in a cot in a separate room. This, says McKenna, led to skewed ideas about what is "normal". "Parents are set up to have the worst possible experience with their children's sleep when they are told that babies should and do sleep through the night. They don't.
They're not designed to sleep through the night."
In fact, he adds, research has shown that babies who sleep "too well", spending a lot of time in deep sleep, are those who are most at risk of cot death. "I stand by my statement, based on my 20 years of research, that co-sleeping between a mother and a baby is inherently protective," McKenna says.
The modern western practice of putting babies to sleep in cots in separate rooms is unique; in most parts of the world, babies still sleep alongside their mothers, just as our ancestors did. "In most Asian countries, they don't know what you mean if you ask where the baby is going to sleep," McKenna says.
In 2000, a paper published by the global task force on sudden infant death syndrome, as cot death is also known, noted the paradox that those countries with the lowest rates of cot death, such as Japan and Hong Kong, are those where bedsharing is the norm.
In the West, bedsharing is still much frowned upon. "We are a society that favours individualism and autonomy over interdependence, and we equate where babies sleep and how they sleep with moral character," McKenna says.
"This issue of morality has never been separated from our general childcare advice, and we tend to devise childcare practices in terms of who we want children to become rather than who they actually are." Nevertheless, studies suggest that, contrary to expectations, babies who share their parents' bed become more independent toddlers and are less likely to have psychiatric problems as adults.
So strong is the taboo against bedsharing that even those parents who do share their beds don't consider themselves bedsharers. If they put the baby to sleep in a cot and only later in the night bring them into bed, they often tell researchers that their baby "sleeps in a cot". This, says McKenna, distorts the results of studies such as the one in The Lancet , making it appear that far fewer people bedshare than is really the case.
One of the main reasons that mothers bring their babies into their beds is that it makes breastfeeding much easier - rather than waiting for a baby to wake up hungry and cry, a mother will detect the baby squirming and can feed her baby without either having to be fully awake. So breastfeeding mothers often find that they sleep better when their babies are alongside them.
With breastfeeding on the rise, thanks to successful promotion of its health benefits, so too is bedsharing, making the safety question even more pressing, Ball says. One of her main problems with The Lancet paper is that it doesn't separate breastfeeders and bottlefeeders in its analysis. She also fears that discouraging bedsharing, especially during the critical first few weeks, might have the unintended effect of discouraging breastfeeding.
Worse still, McKenna says, the most important finding of The Lancet paper was hidden in the rush to condemn bedsharing. "The fact that this study showed a much higher risk of Sids for babies sleeping in a separate room has been made completely invisible. Perhaps more than any other, this study actually confirmed the importance of co-sleeping," he concludes.