Sudden Infant Death Syndrome (SIDS) is the unexplained death, usually during sleep, of a seemingly healthy baby less than a year old. SIDS is sometimes known as crib death because the infants often die in their cribs.
SIDS is not the cause of every sudden infant death. Each year in the United States, thousands of babies die suddenly and unexpectedly. These deaths are called SUID, which stands for “Sudden Unexpected Infant Death.”
SUID includes all unexpected deaths: those without a clear cause, such as SIDS, and those from a known cause, such as suffocation. One-half of all SUID cases are SIDS. Many unexpected infant deaths are accidents, but a disease or something done on purpose can also cause a baby to die suddenly and unexpectedly.
“Sleep-related causes of infant death” are those linked to how or where a baby sleeps or slept.
These deaths are due to accidental causes, such as suffocation, entrapment, or strangulation. Entrapment is when the baby gets trapped between two objects, such as a mattress and a wall, and can’t breathe. Strangulation is when something presses on or wraps around the baby’s neck, blocking the baby’s airway.
These deaths are not SIDS.
SIDS is not:
- SIDS is not the same as suffocation and is not caused by suffocation.
- SIDS is not caused by vaccines, immunizations, or shots.
- SIDS is not contagious.
- SIDS is not the result of neglect or child abuse.
- SIDS is not caused by cribs.
- SIDS is not caused by vomiting or choking.
- SIDS is not completely preventable, but there are ways to reduce the risk.
Facts About SIDS:
- More than 2,000 babies died of SIDS in 2010, the last year for which such statistics are available. 1
- Most SIDS deaths occur in babies between 1 month and 4 months of age, and 90% of SIDS deaths occur before a baby reaches 6 months of age.
- More male babies die from SIDS than girls.
- In most cases, no sign of distress is identifiable. The baby typically feeds normally prior to going to sleep.
- Cardiopulmonary resuscitation (CPR) may be initiated at the scene, but evidence shows a lack of beneficial effect from CPR.
"Why does SIDS happen?"
In the past decade, researchers identified how low oxygen levels, combined with an underlying brain defect, can cause SIDS. Scientists believe a triple-risk model explains many SIDS cases: A baby has a defect in an area of the brain that controls breathing and arousal; the baby is at an age when those brain areas are still immature; and the baby is exposed to an external stress that compromises his breathing or oxygen levels, or that causes overheating.
“To have a SIDS death, you have to have at least one of those [factors], and you have a higher risk if you have two or three of those happening at the same time,” says Fern Hauck, a professor of family medicine at the University of Virginia School of Medicine in Charlottesville.
Sleeping face-down on a soft surface or with soft bedding that can press up against the face can decrease a baby’s oxygen flow too much. When this happens, a normal baby will auto-resuscitate by gasping, crying, turning his head or moving. “It’s thought that SIDS infants have a defective arousal mechanism, which means they stay in that position and gradually suffocate,” Dr. Fern Hauck, a professor of family medicine at the University of Virginia School of Medicine in Charlottesville says. "Overheating is thought to lead to SIDS in a similar way, by suppressing an infant’s arousal response."
The connection between brain defects and SIDS was raised definitively in 2010, when researchers at Children’s Hospital Boston discovered that SIDS babies were deficient in the brain-signaling chemical serotonin in the brain stem. In fact, according to some research, 50 to 75 percent of infants who die of SIDS have a serotonin defect.
Other researchers have found that about 10 to 15 percent of SIDS deaths can be traced to babies with a genetic predisposition for a heart rhythm disorder that can go undetected and lead to cardiac arrest, says Marta Cohen, a pediatric pathologist at Sheffield Children’s Hospital in England. http://www.dallasnews.com/lifestyles/health-and-fitness/health/20130902-new-research-into-sids-gives-parents-clearer-guidelines.ece
How does breastfeeding reduce the risk of SIDS?
Researchers identified 288 studies on SIDS and breastfeeding from 1966 to 2009 and narrowed their analysis to 18 studies that met basic research quality criteria. The results showed that for infants who received any breastmilk for any duration, the likelihood of SIDS was 60% lower.
- For infants who were breastfed at 2 months of age and older, the risk was 62% lower.
- Exclusive breastfeeding without any use of formula for any duration appeared to provide the biggest benefits. The risk of SIDS among exclusively breastfed infants was 73% lower.
Although these findings are based on observational studies and cannot prove a direct cause and effect relationship between breastfeeding and SIDS prevention, researchers say there are several plausible biological reasons. For example, breastfed infants may be more easily aroused from sleep than formula-fed infants at 2-3 months of age, which is within the 2-4 months peak age of SIDS cases. In addition, breastfeeding delivers antibodies known as immunoglobulins that may help protect infants from infection during the period they are most at risk for SIDS.