Possible causes of SIDS

Unfortunately, the exact cause of SIDS is still unknown. There is mounting evidence that suggests some SIDS babies are born with brain abnormalities that make them vulnerable to the syndrome during infancy. Studies of SIDS victims reveal that many infants have abnormalities in a brain structure called Arcuate Nucleus. It is the portion of the brain involved in control of breathing and waking during sleep. Supposedly, these abnormalities may stem from prenatal exposure to a toxic substance, or lack of a vital compound in the prenatal environment, such as sufficient oxygen.

Genetics also plays a large role. SIDS is more common in boys than in girls, and it is more common in certain population groups (see table above). Affected infants may have been born with immature brainstems, making it difficult for them to wake up when in trouble.

Other possible causes:

• stress caused by infection or other factors;
• a birth defect
• failure to develop

What is so special about stomach sleeping?

Among many risk factors, stomach sleeping is probably the most important. Numerous studies have found a higher incidence of SIDS among babies put to sleep on their stomachs than among those sleeping on their backs or sides. Stomach sleeping puts pressure on a child's jaw, therefore narrowing the airway and hampering breathing.

A different group of experts disagrees. They claim that stomach sleeping can increase an infant's risk of re-inhaling his or her own exhaled air, particularly if the infant is sleeping on a soft mattress or with bedding, stuffed toys, or a pillow near the face. When a baby breathes exhaled air, the oxygen level in the body drops and carbon dioxide accumulates. 

See Also: Importance of Infant Immunization

Is this condition contagious?

SIDS is not believed to be contagious, but there is the now-accepted idea that ulcers could be the cause. These ulcers are often caused by infections with Helicobacter pylori bacteria. A study suggests that infections with this same bacterium may also be responsible for many cases of sudden infant death syndrome. This bacterium has been found in 88 percent of examined children who had died from SIDS.