Sudden Infant Death Syndrome

The sudden and unexpected death of a baby for which no cause can be found

  • Most common between the ages of 1 and 6 months
  • Slightly more common in boys
  • Parental smoking and drug abuse are risk factors
  • Genetics is not a significant factor

Sudden infant death syndrome (SIDS), also known as cot death, is devastating for parents of an affected baby. SIDS occurs when healthy babies are put to bed and later found dead for no identifiable reason.

What are the causes?

The cause of SIDS is unknown. However, several risk factors have been recognized, such as parental smoking and drug abuse. Evidence suggests that putting babies to sleep on their fronts and bottle-feeding increase the risk. Babies who are overwrapped, particularly during an illness, can become overheated and may be at increased risk. Parents sometimes report minor symptoms of infection in the hours or days beforehand, but whether these symptoms are significant is not known. The risk of SIDS is slightly higher for siblings of an infant who has died of SIDS and is slightly more common in babies born before 37 weeks (see Problems of the premature baby).

What might be done?

If possible, parents should begin resuscitation immediately after calling for an ambulance. On arrival at hospital, the doctors will attempt to resuscitate the baby, but they are rarely successful. Very occasionally, an infant will be revived, and tests will then be done to try to discover the cause. The baby will receive follow-up care and monitoring to prevent a recurrence.

The sudden death of a baby is an extremely distressing and shocking event. Bereaved parents will need support from doctors, family, and friends, and they may be offered professional counselling (see Loss and bereavement). A postmortem examination of the baby is always carried out to exclude any other causes of death and to reassure the family that the death could not have been prevented. During this period, everyone concerned may experience intense emotions, including guilt, and relationships can be disrupted. These feelings are quite normal. Many bereaved parents find it helpful to contact a support group. If the parents decide to have another child, the doctor will provide advice and support and can arrange for special monitoring.

Can it be prevented?

Many parents feel that SIDS is a threat over which they have no control, but there are ways to reduce the risk. All babies should be placed on their backs to sleep, and pillows should not be used until a baby is over 1 year old (see Positioning your baby for sleep). You should prevent your baby from becoming overheated by making sure the baby’s room is at the right temperature (about 16–18°C/61–64°F), not swaddling or overdressing your baby, and avoiding the use of duvets, quilts, and cot bumpers. You should not sleep with your baby on an armchair or sofa, and neither should you share a bed with your baby, especially if you are very tired or have been drinking or using drugs. Other measures include not exposing your baby to cigarette smoke, and putting your baby’s cot in your bedroom. You may also feel more confident if you have been trained in cardiopulmonary resuscitation. Alarms that alert parents if their baby stops breathing are available but there is no firm evidence that these devices reduce the risk of SIDS.

Self-help: Positioning your Baby for Sleep

From the 2010 revision of the Complete Home Medical Guide © Dorling Kindersley Limited.

The subjects, conditions and treatments covered in this encyclopaedia are for information only and may not be covered by your insurance product should you make a claim.

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