Definition

Cot death is the sudden and unexpected death of a baby for no obvious reason. The post-mortem examination may explain some deaths. Those that remain unexplained after post-mortem examination may be registered as sudden infant death syndrome, sudden infant death, sudden unexpected death in infancy, unascertained death or cot death.

Incidence

The latest figures for sudden infant death syndrome were documented in 2010, when it was stated that 8% of infant deaths were a result of sudden infant death. This equates to 254 unexplained deaths in England and Wales at a rate of 0.35 per 1000 live births. In the United States, 2500 deaths on average occur every year.

There is a higher incidence in boys (0.4 deaths per 1000 live births), which accounted for 59% of unexplained deaths. In girls, the incidence is 0.3 deaths per 1000 live births, accounting for 41% of unexplained deaths.

Most deaths occur within the first year of life. It is very uncommon for an infant less than 1 month or over the age of 1 year to die of sudden infant death syndrome, 90% will die by the time they reach 6 months of age, with a peak incidence of 2 months of age, accounting for 72% of all unexplained deaths to have occurred in infants less than 4 months of age.

Infants with a low birth weight (<2.5 kg) are over four times more likely to die from sudden infant death syndrome than an infant born with a birth weight >2.5 kg.

Mothers less than 20 years of age were 3.4 times more likely to have an infant die with sudden infant death syndrome.

There is a much higher incidence in the north-west of England: 0.53 deaths per 1000 live births.

Measures in place to reduce the risk

In 1991, a campaign was launched to reduce the risk in England and Wales and this has contributed to a reduction by around 71%.

In 1992, the American Academy of Pediatrics launched its Back to Sleep campaign which has led to a drop of 50% in deaths.

Both of these campaigns widely advertised the risk that parents and carers were taking by placing their infants to sleep on their stomachs. Historically, this is how infants had always been put to sleep, and would be the advice of grandparents and health care professionals.

Advice to parents to help reduce the risks

There are a number of risk factors that can contribute to sudden infant death syndrome. The education of parents is paramount in helping to reduce the numbers of infant deaths that still occur:

• Always put the infant to sleep on his/her back
  
• Keep the cot in the adults’ room for the first 6 months of age
  
• Recommend the baby is placed with his/her feet near to the bottom of the cot to prevent getting underneath bedding
  
• Do not smoke during pregnancy or after the birth of the infant
  
• Do not allow anyone to smoke in the same room as the infant
  
• Do not share a bed with an infant
  
• Do not sleep with an infant in an armchair or on a sofa
  
• Be more vigilant if taking drugs or alcohol
  
• Do not allow the infant to become too hot – keep bedding and clothing to a minimum and keep the room they are sleeping in cool rather than over-heated
  
• If the infant was born prematurely, was born with a low birth weight or born to a mother under the age of 20 years, the infant will have an increased risk. These infants should be observed more frequently.

Smoking

There is evidence to support that smoking can significantly increase the risk of sudden infant death syndrome. This applies to mothers who smoke during pregnancy, after pregnancy and any other adults who smoke around an infant. The environment an infant should be in is completely smoke-free as an infant in a smoky environment is eight times more likely to die from sudden infant death syndrome.