Viral infection, passive smoking, sleeping position – do any of these cause cot death? No one knows for sure but here’s the latest information from The Foundation for the Study of Infant Deaths

Since The Foundation for the Study of Infant Deaths launched their Reduce the Risk of Cot Death’ campaign in 1991, the number of babies dying suddenly and unexpectedly has fallen by 70%. But we still don’t know what causes cot death.

In the UK, whenever a baby dies for no obvious reason, a post-mortem examination is performed to try and discover why they died. Deaths that remain unexplained are registered as sudden infant death syndrome (SIDS), sudden infant death, sudden unexpected death in infancy, unascertained or cot death.

Eight babies die as cot deaths every week in the UK. It claims more babies’ lives than meningitis, road traffic accidents, leukaemia or any other cancer. This tragedy can happen to any baby, but some are more at risk, including babies of low birthweight and those born prematurely. Boys seem more susceptible, but only marginally.

Over 90% of cot deaths occur in babies aged under six months and the risk recedes quickly as children grow older. Of the 419 babies who died in 1999, only 21 were over a year old.

Cot death can happen anywhere and at any time. Some babies die in their parents’ arms or in a pram, but most die in their cots.

Families on lower incomes generally experience poorer health and cot death is disproportionately high in this group. It is difficult to give exact facts and figures, because official statistics are based on the father’s occupation at the time of the baby’s death, meaning that many babies with unmarried parents are not included. But broadly, while cot death can happen to babies in any income group, almost 70% now occur among poorer families.

The rate of cot death in the UK is similar to countries such as Canada and Sweden. In the Netherlands and Hong Kong the rate is lower, but it is higher in New Zealand and the USA.

In the past cot deaths used to occur more often in the winter months, but since the introduction of the Reduce the Risk of Cot Death campaign, this peak has been levelling out. In the ’70s and ’80s the cot death rate remained fairly constant in England and Wales, at about 2 per 1,000 live births. After ‘Reduce the Risk’, the incidence halved dramatically within one year. In total, cot death has now fallen by 70% over the past decade. So there has never been a safer time to have a baby.

Reducing the risk

While the actual causes of cot death remain a mystery, you can reduce the risk for your baby.

• Place your baby on its back to sleep.
• Cut smoking in pregnancy – fathers too.
• Do not let anyone smoke in the same room as your baby.
• Do not let your baby get too hot.
• Keep baby’s head uncovered. Place your baby with feet against the foot of the cot, to prevent them wriggling down under the covers.
• If your baby seems unwell, seek medical advice promptly

One of the most important studies in recent years is the Confidential Enquiry into Stillbirths and Deaths in Infancy (CESDI). This study was the largest ever to be conducted in England and Wales and examined the circumstances of 325 babies who died suddenly and unexpectedly. As well as reinforcing the Reduce the Risk advice, the findings also made it possible to give further advice.

• Do keep your baby’s cot in your room with you for the first six months.
• Do not fall asleep with your baby on a sofa.
• Do not share a bed with your baby if you smoke (even if you don’t smoke in bed), have been drinking alcohol, taking drugs or are excessively tired.

A study published in October 2000, carried out at Manchester Royal Infirmary found the DNA of a bacteria called Helicobacter pylori in 28 cot-death babies. This bacterial infection, linked to ulcers, stomach cancer and heart disease, is common in adults but rare in babies.

It is uncertain, at this stage, whether the research findings will help identify babies at risk of cot death. Joyce Epstein, FSID’s Director, said: ‘These are interesting findings that may help explain why over-wrapping, front sleeping and minor infections may create difficulties for babies.’

The researchers suggested that the bacteria could be spread from parent to baby when parents suck their babies’ dummies to clean them, or even through kissing, though FSID says the latter is unfounded and parents should not be worried about kissing their babies.

Since it was established in 1971, FSID has spent over £8 million on research. Current funding is supporting these projects:

• Airway function in low birthweight infants.
• Ways to reduce babies’ exposure to passive cigarette smoke.
• Interactions between parents and their babies when room- or bed-sharing.
• Antenatal and post-natal physiological development of babies born to mothers living in difficult circumstances and how this affects mother/infant interaction.
• How physiological control mechanisms are influenced by age, sleep position, passive smoking and other risk factors.
• What influences parents in making childcare decisions.

If you, or anyone you know, has had a baby die suddenly and unexpectedly then you may wish to contact FSID who offer:

• A 24-hour helpline (020 7233 2090).
• A helpline phonecard so bereaved parents can call the helpline free of charge.
• A free booklet called ‘When a baby dies suddenly and unexpectedly’ which explains what happens after a baby dies and the feelings and emotions families may experience.
• Specially trained befrienders, who may have gone through a similar experience.