Previously termed ‘cot death’ and ‘Sudden Infant Death Syndrome’, this implies that a baby has been found dead for no obvious reason, usually between the ages of 1 month and 1 year. Amongst them will be some babies where a definite cause is found at post-mortem examination, for example an overwhelming infection, one of the many rare METABOLIC DISORDERS, a congenital abnormality or – for a small number – infanticide. The remaining babies, for whom it is not possible to give a cause of death, the term SUDI, is usually stated on the death certificate. Although the reasons are not fully understood, some factors which put babies at a greater risk are known; by far the most important are placing them down to sleep prone (on their front) rather than their back and parental smoking or co-sleeping. Other risk factors include babies who were premature, those of very young mothers and babies sleeping with too many clothes in too hot a room. More deaths occur in winter than summer, breast fed babies are less likely to die, and there is some evidence that having a dummy reduces the risk. Well over 1,500 such cases are thought to have occurred in the United Kingdom each year until 1992, when government advice was issued about laying babies on their backs. The figure is now fewer than 200.
Parents can reduce the risk as follows:
Neither parent should smoke in the house and nobody in the baby's room
Babies should sleep on their back, not front or side
They should not be overheated and their head should be left uncovered
Their feet should be to the foot of the bed so they cannot wriggle down under the covers
A parent should not sleep on a sofa or armchair with their baby
The best place for babies to sleep for their first 6 months is in a cot in their parents’ room
Babies born prematurely and those under 3 months should never sleep with their parents
A dummy at night is a good idea, as is breastfeeding
The baby should not be in parents’ bed if either is a smoker, they have been drinking alcohol, taken drugs that cause drowsiness or are abnormally tired.
These are unknown, with possible multiple aetiology. Prematurity and low birth weight may play a role. The sleeping position of a baby and an over-warm environment may be major factors, since deaths have fallen sharply since mothers were officially advised to place babies on their backs and not to overheat them. Some deaths are probably the result of respiratory infections, usually viral, which may stop breathing in at-risk infants, while others may result from the infant becoming smothered in a soft pillow. Faults in the baby's central breathing control system (central APNOEA) may be a factor. Milk allergy is a possible factor, as may be a sudden disturbance of fluid balance resulting from bottle feeding; inhalation of milk is a further possible contributory cause. Other possible factors include poor socioeconomic environment; vitamin E deficiency; or smoking, drug addiction or anaemia in the mother. Help and advice may be obtained from the Foundation for the Study of Infant Deaths and the Cot Death Society (www.fsid.org.uk).