Cot death is when a baby under a year old dies suddenly and unexpectedly. If after a detailed investigation the death remains unexplained, the medical term is sudden infant death syndrome (SIDS). It's also known as sudden unexplained death in infancy (SUDI).
More than 200 babies die suddenly and unexpectedly in the UK every year. Cot death can happen to any baby, but it's more common in babies between two to four months, premature babies, and babies with a low birth weight. It's also more common in baby boys than girls.
Most cot deaths happen when a baby is asleep in their cot at night.
If your baby was one of twins, triplets or more, you may need to take your other baby (or babies) into hospital for observation. This is important, as some rarer causes of sudden death in infancy run in families.
A thorough investigation will be done to try to find out why your baby died and to gather information that may help to prevent cot deaths in the future. This investigation is standard procedure in all cot deaths and doesn't in any way imply suspicion or blame surrounding your baby's death.
The people who will be involved in the investigation can vary depending on where you live. They may include a coroner (an official who enquires into sudden, unexpected deaths), a paediatrician (a doctor who specialises in children's health), a pathologist (a doctor who performs the autopsy), social workers, police officers, health visitors and midwives.
When the full results from the investigation are available, a case discussion meeting will take place, which will be attended by all of the people involved in the investigation. This may be up to 12 weeks after the death of your baby.
You will be kept informed of the investigation procedure and progress at all times. At the end of the investigation, a doctor will usually discuss the findings with you.
If a specific cause of death is found, this will be registered on the death certificate. If your baby’s death remains unexplained after the investigation, the death is usually registered as SIDS or SUDI.
Less than half of all cot deaths have a specific cause. Possible causes include a serious infection, an accident or a previously unknown problem that your baby was born with (a congenital condition). This may include a heart or lung problem. However, there are a large number of potential causes, which is the reason why the investigation has to be so thorough.
If no specific cause is found to explain the death of your baby, it's defined as SIDS or SUDI. Research suggests that a number of different factors may be linked to SIDS. These factors aren't thought to actually cause SIDS, but may make your baby more at risk. These factors can be divided into two groups – those that you can modify and those you can’t.
Factors you don't have any control over and can’t modify include:
Risk factors you do have control over and can change or modify include:
Although it’s impossible to prevent SIDS, there are a number of things you can do to reduce the chances of it happening.
Exposure to cigarette smoke (during pregnancy or after birth) is known to increase the risk of cot death. One in five deaths from SIDS are thought to be linked to passive smoking.
For the first six months, the safest place for your baby to sleep is in a cot or Moses basket in your bedroom.
Don't share a bed with your baby if you or your partner:
There is some evidence to suggest that giving your baby a dummy when you settle him or her to sleep may help to reduce the risk of cot death. However, more research is needed to understand why this is before official recommendations can be made regarding the risks and benefits of using dummies.
If you're breastfeeding, don't introduce a dummy until around a month (wait until your baby is breastfeeding well). Also, reduce the use of a dummy gradually when your baby is around six to 12 months to prevent dental problems.
Babies who are breastfed are less likely to die from cot death than babies who have only ever received formula milk.
Keep your baby at the right temperature.
There is no evidence that breathing or movement monitors help prevent cot death so only use one if your doctor advises you to.
Even after you take as many precautions as possible, babies can and do still die from cot death. You may have many different emotions and some parents have overwhelming feelings of guilt and anger. Family and friends can be a valuable source of help and comfort at this difficult time. They can also help in practical ways, for example if you have other children, they can look after them for you, prepare meals and do the shopping.
Dedicated charities, support groups and associations offer advice and help to families affected by cot death. It may also help to talk to a counsellor who specialises in helping people cope with grief. Your GP or health visitor can help you find a suitable counsellor or support group in your area.
The decision to have another child after losing a baby to cot death isn't an easy one. You will know if and when you're ready and when it’s the right time for you.
Care of the next infant (CONI) schemes are available in many areas. They offer advice, support, increased monitoring for your new baby and frequent check-up visits. Ask your GP or midwife if there is a CONI scheme in your area. If there isn't, your local health authority may run its own equivalent scheme. They may be able to offer you additional support during your pregnancy and after the birth of your new child.
Reviewed by Rachael Mayfield-Blake, Bupa Heath Information Team, August 2013.
For answers to frequently asked questions on this topic, see FAQs.
For sources and links to further information, see Resources.
This information was published by Bupa's Health Information Team and is based on reputable sources of medical evidence. It has been reviewed by appropriate medical or clinical professionals. Photos are only for illustrative purposes and do not reflect every presentation of a condition. The content is intended only for general information and does not replace the need for personal advice from a qualified health professional. For more details on how we produce our content and its sources, visit the about our health information page.