The American Academy of Pediatrics defines SIDS as the sudden death of a baby under 1 year of age for which no cause can be determined after thorough clinical investigation including an autopsy.
The updated recommendations were released Monday by the American Academy of Pediatrics (AAP).
While the AAP SIDS panel came out strongly against bed sharing, it concluded that room sharing -- placing the infant's crib or bassinet in the caregivers' bedroom at night -- reduces the risk of sudden infant death during sleep.
The panel also came out for the first time against side sleeping, concluding that the risk that the sleeping infant will roll over onto his or her stomach is too great.
Dramatic Reduction in SIDS Deaths
It has been a little over a decade since AAP first told parents to place sleeping infants on their backs to protect them against SIDS. Since then, the number of unexplained sudden infant deaths in the United States has dropped by half, from around 5,000 cases a year during the early 1990s to less than 2,500 last year.
The experts now say that increased use of pacifiers at naptimes and bedtime could have a similarly dramatic impact on SIDS deaths.
"The studies have consistently shown that risk declines with pacifier use," says SIDS researcher and panel member Rachel Moon, MD, who is pediatric medical director at Washington's Children's National Medical Center. "We don't really know why. But the evidence was too compelling to ignore."
Cutting SIDS Deaths Even More
A newly published review of the research suggests that SIDS deaths could be reduced significantly if all infants were put to sleep with pacifiers.
Researchers estimated that one death could be prevented for every 2,733 births or roughly 1,500 total deaths a year in the United States.
Many experts now say that SIDS may result from an early life deficiency in the ability to wake up. Arousal from sleep is believed to be an important survival mechanism that may be impaired in vulnerable infants, the theory goes.
Back sleeping and pacifiers may keep babies from sleeping too soundly, says SIDS researcher Fern R. Hauck, MD, MS, who conducted the review.
She tells WebMD that a pacifier should be offered to an infant at naptimes and bedtime, but if the baby won't take it don't force the issue.
"Try again in a day or so," she says. "Babies who initially refuse a pacifier usually end up taking if it is offered multiple times over several days or weeks."
The new recommendations call for parents to give babies pacifiers during sleep through the first year of life. While there have been concerns that pacifier use interferes with breastfeeding or causes dental problems later in life, the AAP panel did not find compelling evidence to back this up.
It did recommend that pacifier introduction be delayed until after the first month of life for babies who are breastfed to ensure that breastfeeding is firmly established.
Family Bed Revisited
While earlier SIDS guidelines cautioned that bed sharing could be dangerous, they did not specifically advise against the practice, as the new guidelines do.
While infants may be brought into the parents' bed for nursing or comforting during the night, they should be returned to their own crib or bassinet when the parents go to sleep.
The task force concluded, however, that there is growing evidence that room sharing during the first months of life is beneficial.
Moon says room sharing may, again, keep vulnerable infants from sleeping too deeply.
Other recommendations to reduce SIDS risk include:
You should place infants on a firm sleep surface, covered by nothing more than a sheet.
Keep soft objects and loose bedding out of the crib: Stuffed toys, pillows, and quilts should be removed from the crib when the baby is sleeping.
Mothers-to-be should not smoke during pregnancy, and babies should not be exposed to second-hand smoke.
Avoid overheating. Infants should be lightly clothed during sleep, and the room should not be too hot.
Moon tells WebMD that the risk of SIDS can be dramatically reduced if all the guidelines are followed, but they can't be eliminated.
Additional information in the AAP report stated no association between SIDS and certain immunizations. There is also no consistent evidence that breastfeeding can protect a baby from SIDS.
"We know a lot more than we did five or 10 years ago, but it is like having half of the puzzle solved," she says. We don't yet know what the full picture will look like."
SOURCES: American Academy of Pediatrics policy statement on SIDS, Oct. 10, 2005. Hauck, F.R., Pediatrics, November 2005; vol. 116: pp. 716-723. Fern R. Hauck, MD, MS, Departments of Family Medican and Public Health Sciences, University of Virginia School of Medicine, Charlottesville, Va; and Children's National Medical Center, Washington. Rachel Moon, MD, prediatric medical director, Children's National Medical Center, Washington.
Reviewed by Ramaz Mitaishvili, MD