Back to Sleep campaigns have slashed cot death rates around the world but most of their success can be attributed to undoing the harm caused by earlier incorrect advice.
A comparison, by scientists at the University of Virginia, of cot death rates in 15 countries before and after campaigns to reduce front sleeping and other risk factors, found that rates declined by more than 50% in most countries. Most campaigns started in the early 1990s and recorded cot death rates fell (total infant mortality also fell) in the period 1990 to 2005 by over 80% in France, Austria, Scotland and Ireland and by almost 60% in the USA and Canada (in 2016 over 20% of American babies still slept on their fronts).
Figure 1 shows cot death rates in England and Wales over the period 1971-2005 (5 year intervals except red bars). The UK Back to Sleep campaign was launched in December 1991 and the following year cot death rates fell by 60%. Rates peaked in 1986 before evidence linking cot death and front sleeping started to emerge. The Health Secretary had no doubts that the 1992 fall was due to the Back to Sleep campaign. UK cot deaths are currently at record lows after 25 years of Back to Sleep and all of its advice about reducing cot death (see Lullaby Trust).
Figure 1 not only shows the fall in cot death rates since 1986 but also shows how rates increased steeply after 1971. More than 10,000 extra British babies died during this 20 year “epidemic” of cot deaths (1971-1991) and well over 50,000 in Europe, Australasia and the USA . This epidemic was caused by the promotion of front sleeping by health professionals and baby care writers. In 1995, I published the results of an ad hoc survey of advice about sleeping position given in baby care books previously obtained from acquaintances and local public libraries. Books published before 1988 were almost unanimous in recommending front sleeping with one even suggesting that it was dangerous to leave a baby alone on its back in case it choked on regurgitated milk (see for sample quotes). Even the 1984 edition of the Pregnancy Book published by the Health Education Council recommended front sleeping:
“For the first two months or so, the safest way for babies to sleep is on their fronts, head to one side, or else curled up on one side.”
Compare this with advice in the 1993 edition:
“Babies laid to sleep on their tummies are more at risk of cot death than babies laid down to sleep on their backs or sides”
Babies in the UK traditionally slept on their backs but the side position started being used in the early 20th century because of the perceived danger of inhaling regurgitated milk. The 1955 British edition of Dr Spock’s famous baby and child care book recommended back sleeping and did not mention side sleeping (see). A Chief Medical Officer’s (CMO) 1993 report, supports the general belief that front sleeping was uncommon ( under 5%) before 1971 but rose thereafter e.g. only 4% of a sample of babies in Northern Ireland slept on their fronts in 1965-7. Front sleeping became the most popular choice in many countries during the 1980s; the CMO report and a 1992 report by the American Academy of Pediatrics (AAP) give evidence of these changes. The CMO report suggests that evidence to fully document these changes does not exist e.g. although the AAP report says that in 1992 most infants in the USA were placed on their fronts, the evidence source is “personal communication”.
Most sources like the AAP report suggest that less perceived danger of inhaling vomit was an important justification for front sleeping . Studies from special care baby units also suggested that certain measures of lung function were improved in babies with respiratory distress; the AAP report details these reductionist studies on lung function and sleeping position and other claimed benefits of the front position like better sleeping. It seems that very limited evidence or speculation, particularly from special care baby units, led to almost unanimous advice from medical professionals and baby care writers to put babies on their fronts.
I recently suggested that governments were slow to advise against front sleeping (e.g. US national campaign started in 1994). In 2005, a group from London’ Institute of Child Health claimed that there was published evidence of significant increase in cot death risk in front sleepers available in 1970 i.e. before the rise in front sleeping. In 1987, a widely publicised medical lecture in Holland presented evidence that front sleeping was potentially dangerous and a policy of recommending against front sleeping was introduced the next day in Dutch baby clinics; Dutch cot death rates fell by 55% between 1986 and 1988. A media campaign by radio and television personality Anne Diamond seems to have helped hasten the Department of Health’s launch of Back to Sleep in December 1991. To balance the speedy Dutch response, the Dutch were also early leading early advocates of front sleeping and a public lecture campaign in Holland in 1972 amounted to a de facto Front to Sleep campaign (CMO).
There are risks for any public health or medical intervention that has not been subjected to in-depth, independent, expert evaluation especially if based upon assumption and weak evidence. Had NICE existed and been consulted in 1971, then this public health disaster would probably have been avoided.