As a mother to a newborn, I am completely neurotic about SIDS. To make
matters worse, my son seems to sleep more deeply and more comfortably
on his stomach. I have heard that there is a statistical correlation
between SIDS and infants sleeping on their stomach, but I'd like to
know to what degree this is really thought to be a cause. And are
there situations where sleeping on the tummy is recommended? I have
heard from some mothers whose children were preemies that the hospital
kept the infants sleeping on their stomachs while in the hospital.

patootie...

I'm afraid I must persuade you to dishonor your son's preference
in this matter. I first did a Google search for:

SIDS "sleeping on ~their stomachs"
://www.google.com/search?q=SIDS+%22sleeping+on+%7Etheir+stomachs%22

This turned up innumerable results which all made it clear
that studies have been done which demonstrate a definite
correlation between SIDS and infants sleeping on their
stomachs.

One such page, from the award-winning 'Healthy Child Care'
site, notes:

"'Back to Sleep' is the name of an important campaign
 created to let those who care for infants-parents,
 childcare providers, relatives, and others-know the
 importance of putting infants to sleep on their backs,
 not their stomachs."

While not the only cause for SIDS, the site states:

"A major risk factor to babies is sleeping on their stomachs.
 There is an interesting, alarming, and compelling history
 behind this discovery. A few years ago, researchers in
 several countries wondered if the age-old tradition of
 putting babies down on their stomachs - and faces - while
 they slept could possibly contribute to the tragedy of
 SIDS. Research studies produced surprising and consistent
 results. Babies sleeping on their stomachs are much more
 likely to die suddenly and unexpectedly, than those
 sleeping on their backs or sides. There are probably
 several reasons contributing to this, including slight
 build up of carbon dioxide, perhaps significant increases
 in body heat, and obstruction of the airway by bed clothing
 or the mattress."

And, the statistical evidence to back this up:

"The U.S. has joined many countries in launching public
 education programs urging caregivers to put infants on
 their backs to sleep, not prone, on their faces and
 stomachs. The results have been startling. New Zealand,
 the first nation with such a program, noted a dramatic
 drop in SIDS deaths. In the U.S., as more babies are
 put to sleep on their backs, the number of SIDS deaths
 also has decreased. Sleeping on the side is better than
 the stomach, but sleeping on the back is by far the best
 and safest. During the past few years, the number of
 babies sleeping on their backs has increased by nearly
 66 percent while the SIDS rate has decreased by about
 40 percent."
More on the page:
http://www.healthychild.net/Articles/Sleep6.html


Just to be fair, I ran a search without the term SIDS,
in hopes of finding a reference to some benefit of 
infants sleeping on their stomachs:

infants "sleeping on the stomach"
://www.google.com/search?q=infants+%22sleeping+on+the+stomach%22

To my surprise, almost every link this search turned up
mentioned SIDS anyway!

Additionally, one of the links resolved the mystery of
how the practice started - which also resolves the 
question of its potential benefits to premature infants.

I can't translate the homepage of this Swedish website,
but there is a link on the front page which is labelled
as "Evidence-based health promotion for children and 
adolescents in Stockholm County". And, on this page about
'Sudden Infant Death', near the bottom:

"In most cultures infants sleep on their backs. It was
 not until the 1960s and 1970 that children in the
 western world started to sleep on their stomachs to a
 greater extent - on the recommendations of paediatricians.
 This well-intentioned advice was based on experiences
 from hospital care. Infants who are immature at birth
 often vomit and can have difficulties preventing the
 stomach contents from going into the lungs. For these
 children sleeping on the stomach is an advantage. For
 all other children, however, the benefits of sleeping
 on the back are greater."
The rest of the page is very informative, as well:
http://www.cbu.dataphone.se/EngBarnrapp/suddenin.html


Finally, I thought I'd see about adults sleeping on the
stomach, and found this on a page from the Dubai Furniture
Manufacturing Company:

"Sleeping On Your Stomach"

"Normally, it is recommended that you avoid sleeping on
 your stomach. If you do, your face is forced to turn to
 either the extreme right or left in order to breathe.
 This may cause undue stress in the joints of the cervical
 spine, as well as stretching and/or shortening of the
 muscles and ligaments on one side of the spine or the
 other. Stomach (prone) sleeping may also help cause the
 rib cage to shift due to the body weight on the chest
 and may contribute to stress in the low back, extending
 into the hips, legs and feet. Symptoms of stomach
 sleeping may include neck and shoulder stiffness, acute
 torticollis (wry neck), and morning headache."
http://www.mattressleader.com/sleep.html


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sublime1-ga

Although not the answer I'd like to have, it was immensely helpful! Thank you!