Sudden infant death syndrome (SIDS), or cot death as it’s sometimes known, is every parent’s nightmare. As its name suggests, SIDS is the term used to describe the sudden and unexpected death of a baby for no obvious reason and it’s the leading cause of death in babies over one month old. In fact, it claims more lives than meningitis, leukaemia, other forms of cancer, household and road traffic accidents and seven babies a week die from SIDS in the UK alone.

In 1991, the Reduce the Risk campaign was introduced in England in Wales. It highlighted the key ways of reducing the risk of cot death, such as putting your baby to sleep on his back and getting the temperature of the room right. According to the Foundation for the Study of Infant Deaths (FSID), it seemed to have a significant effect, as since then the number of babies dying of cot death has fallen by about 75 per cent.

SIDS can affect any baby, although premature infants, low-birth weight babies and boys tend to have a higher risk. SIDS is an uncommon occurrence in babies less than a month old, but the risk rises to a peak during the second month, diminishing as the baby gets older. “Nearly 90 per cent of cot deaths have occurred by six months, and very few occur after a year,” explains a spokesperson for FSID.

A death can occur at any time of year, but is more frequent during the colder winter months, and it can happen anywhere and at any time – not just when a baby is in their cot. The key factor is that they’re normally asleep, so they could be in a pram or lying in their parent’s arms.

Potential causes

The exact reason for SIDS is often unclear. In less than half of all deaths, a post mortem examination reveals a specific cause, such as an infection, metabolic disorder, accident or congenital abnormality. But some cases still remain uncertain. “For the SIDS cases that remain unexplained, researchers think there are likely to be undiscovered causes,” say FSID. “For many, it is likely that a combination of factors affect a baby at a vulnerable stage of development.”

Research is constantly underway and recent findings suggest a genetic defect may hold the clue to cot death. A team from the University of Bristol joined forces with American experts and discovered that many different types of brain cells are essential for normal breathing, but only a tiny number play a role in the gasping reflex.

It’s been thought for a while that a failure to gasp may be linked to cot death, but until now no-one has understood why it should happen. Now it seems that a genetic defect may prevent some babies who stop breathing to kick-start their lungs.

“Our findings are exciting,” said Professor Walter St. John, one of the researchers. “They demonstrate that emergency breathing or gasping is regulated by different mechanisms than those for normal breathing. Sudden infant death syndrome results from inadequate auto-resuscitation. Children that die have been unable to produce a gasping-like response after they stop breathing, to reactivate their normal breathing and reactivate their heart.”

The research could help shed light on high profile cases such as those of Angela Cannings, Sally Clark and Donna Anthony, who were wrongly convicted of killing their babies. The team are now going on to investigate whether the brains of cot death babies are different to those of other children.

Cot death isn’t something to become complacent about and, despite the fervent message about the need to put babies to sleep on their back, a recent survey by FSID discovered that 21% of mothers still don’t always do this, resulting in a nine times increased risk of cot death. FSID suggest this could be because parents are worried about ‘flat head syndrome’, or plagiocephaly. The condition which is entirely cosmetic, almost always corrects itself within a year and could be avoided if parents give their baby plenty of awake time on the front or sitting up.

“We’re really alarmed to see that a fifth of babies aren’t being placed on the back to sleep,” said Joyce Epstein, director of FSID. “Our fear is that the lifesaving message to sleep babies on the back to reduce the risk of cot death will be undermined by a mistaken perception that flattened heads poses a greater danger. It does not.”

Reducing the risk

There are a number of practical steps you can take to reduce the risk of SIDS. The top tips recommended by FSID are:

* Stopping smoking during pregnancy – and fathers, too.

* Not smoking in the same room as your baby.

* Placing your baby on his back to sleep.

* Avoiding letting your baby get too hot – the ideal temperature is 16-20 degrees.

* Keeping your baby’s head uncovered when sleeping.

* Place your baby’s feet at the foot of the cot, to prevent wriggling down under the covers.

* Having your baby sleep in a cot in your bedroom for the first six months.

* Not sharing a bed with your baby if you or your partner smoke, you feel very tried, you take any drugs or medication that makes you sleepy or you’ve been drinking alcohol.

* If your baby is unwell, seek medical advice promptly.

 By Rachel Newcombe