MN SID Center
What is SIDS?
SIDS is the sudden, unexplained death of a baby younger than 1 year of age that doesn’t have a known cause even after a complete investigation.
Each year in the United States, thousands of babies die suddenly and unexpectedly. These deaths are called SUID (pronounced SOO-idd), 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. They are due to accidental causes, such as: suffocation; entrapment, when baby gets trapped between two objects, such as a mattress and wall, and can’t breathe; or strangulation, when something presses on or wraps around baby’s neck, blocking baby’s airway. These deaths are not SIDS.
SIDS is ...
- the leading cause of death in infants from 1 month to 1 year of age, with most deaths occurring between 1 month and 4 months
- sudden and silent—the infant was seemingly healthy
- a death often associated with sleep and with no signs of suffering
- a recognized medical disorder
- determined only after an autopsy, an examination of the death scene, and a review of the infant's and family's clinical histories
- a diagnosis of exclusion
- an infant death that leaves unanswered questions, causing intense grief
SIDS is not ...
- preventable, but the risk can be reduced by placing the baby on his or her back to sleep on a firm surface, by making sure the baby has a smoke-free environment, and by keeping the baby from being overheated
- caused by vomiting and choking or by minor illnesses such as colds or infection
- caused by the diphtheria, pertussis, tetanus (DPT) vaccines or other immunizations
- child abuse or neglect
- the cause of every unexpected infant death
Reduce Risk/Keep Baby Safe
Research shows that following safe sleep rules can help lower your baby's risk of Sudden Unexpected Infant Death Syndrome (SUIDS) and protect baby from suffocation and accidents during sleep.
Healthy babies should sleep on their backs. One of the most important things you can do to help reduce the risk of SIDS is to put your healthy baby on his or her back to sleep. Do this when your baby is being put down for a nap or to bed for the night. Talk to everyone who cares for your baby- grandparents, child care providers, babysitters - about the importance of placing your baby on his back for sleep. Since the "Back to Sleep" campaign started in 1984, the SIDS rate in the United States has dropped by more than 50%.
As baby gets older, continue t place him on his back when you lay him down for sleep. When baby starts rolling over, there is no need to constantly re-position him onto his back while he sleeps. This is a good time to look at where baby is sleeping to make sure safe sleep practices are still being followed. Check that baby is sleeping in a safety approved crib and make sure there are no pillows, fluffy bedding, stuffed toys or pillow-like bumpers in the crib.
Check with your doctor or nurse - Most babies should sleep on their backs, but a few babies have health conditions requiring them to sleep on their tummies. If your baby was born with a birth defect, or has a breathing, lung or heart problem, be sure to talk to a doctor or nurse about which sleep position is best for your baby.
Some parents worry that their baby may choke on spit-up vomit when back sleeping. There is no evidence that sleeping on the back causes choking. Millions of babies around the world now sleep on their backs and doctors have not found and increase in choking or other problems.
Talk to your doctor or nurse if you have questions about your baby's sleep position.
Where baby sleeps is important too. The safest place for baby to sleep is on his back in his own safety approved crib with a firm mattress covered by a tight fighting sheet. Remove fluffy bedding, pillows or stuffed toys from baby's sleep area. Research has shown that such things can pose a risk for suffocation as well as SIDS.
Babies, like adults, should move and be in different positions throughout their day. Limit use of car seats, infant carriers, infant swings, etc. Use tummy time for play. Place baby on her stomach when he is awake and being supervised. Tummy time strengthens neck and shoulder muscles, encourages motor development, and helps baby learn to use both sides of his body. These are important skills to build as baby continues to grow and develop physically, emotionally, and socially. Remember: back to sleep, tummy to play.
Enjoy your baby! Remember, most babies are born healthy and most stay that way. Don't let the fear of SIDS spoil your joy and enjoyment of having a new baby.
• Helping Baby Back to Sleep [PDF]
This information is from the National Institute of Child Health and Human Development, the American Academy of Pediatricians, First Candle/SIDS Alliance, and the Association of SIDS and Infant Mortality Programs.
Grief support and resources
If you or someone you know has experienced the death of an infant, please call the MN SID Center for more information, support groups, and resources: 612-813-6285 or toll free 1-800-732-3812.
Many parents experience guilt, anger, fear, shock, denial and depression. Their suffering is a very personal experience and can appear in many different ways. To all parents, though, the loss of their baby is devastating.
Other children in the family are also deeply affected by the death. Their mourning will be as individual as that of their parents. If very young, these brothers and sisters may express their feelings through actions and play rather than talking. They may develop physical symptoms or regress to less mature behavior. Older children may develop problems in the school setting, or may suddenly develop extreme fears. Like their parents, the children's reactions can include normal feelings such as anger, guilt, anxiety and great sadness.
Often, the death of an infant touches family, friends, neighbors, co-workers, and relatives as well. The grandparents' grief, especially, may be intensified by the grief for their own child as well as the loss of a grandchild. Occasionally, the death may occur while the infant is in the care of a child care provider. They, too, are significantly affected by death.
Frequently Asked Questions
What is SIDS?
What are the most common characteristics of SIDS?
SIDS is unexpecterd, usually occurring in healthyappearing infants under 1 year of age. A SIDS death occurs quickly and usually during sleep. SIDS is rare during the first month of life. Although SIDS can occur in older infants, most SIDS deaths occur by the end of the sixth month, with the greatest number occurring in infants between 2 and 4 months of age (AAP, 2000).
In the United States, more SIDS cases are reported in the fall and winter than in spring or summer. SIDS occurs more often in boys than in girls (approximately a 60- to 40-percent male-to-female ratio). African-American and American-Indian infants are two to three times more likely to die from SIDS as other infants (AAP, 2000; NICHD, 2001). Several Government agencies are intensifying efforts to reach these populations with the latest information about SIDS.
How many babies die from SIDS?
Each year between 1983 and 1992, the average number of reported SIDS deaths ranged from 5,000 to 6,000. Over the past few years, especially since the mid 1990s, the number of SIDS deaths has declined significantly. The National Center for Health Statistics (NCHS) reported that in 2002 in the United States, 2,295 infants under 1 year of age died from SIDS (NCHS, 2004). Still, when considering the number of live births each year, SIDS remains the leading cause of death in the United States among infants between 1 month and 1 year of age and the third leading cause of death overall among infants less than 1 year of age (NCHS, 2004).
Although the overall SIDS rates have declined in all populations throughout the United States, disparities in SIDS rates and prevalence of risk factors remain in certain groups. SIDS rates are highest among African Americans and American Indians and are lowest among Asians and Hispanics (NICHD, 2001).
How is a SID death diagnosed?
By definition, a SIDS diagnosis requires a complete autopsy, a thorough death scene investigation, and a clinical history. A death is diagnosed as SIDS only after all probable alternatives have been eliminated—in other words, SIDS is a diagnosis of "exclusion."
Often, the cause of an infant death can be determined only through a process of collecting information; conducting sometimes complex forensic tests; and by talking with parents, other caregivers, and physicians.
Medical and legal experts rely on three methods to determine a SIDS death:
1. a thorough death scene investigation
3. review of infant's and family's medical records and histories.
When a death is sudden and unexplained, investigators, including medical examiners and coroners, call on forensic experts, who apply their expertise in medicine and the law to help determine a cause of death. SIDS is no exception.
In most cases, the death investigation is led by the medical examiner or coroner for the county, district, or State in which the death occurred. Deaths suspected to be SIDS usually require law enforcement officers to conduct a thorough death scene investigation. The medical examiner/coroner gathers information from the death scene and case histories and presents this information to the pathologist (usually board certified or with credentials in forensic pathology). The pathologist conducts or supervises the autopsy and assesses results of the autopsy, death scene investigation, and case histories to determine whether a SIDS death has occurred. The pathologist issues a SIDS diagnosis when there is no other apparent cause for the infant's death (Valdes-Dapena, 1995).
1) A Thorough Death Scene Investigation
Although it may be emotionally painful for the family, a death scene investigation will help shed light on the cause of death by providing a detailed record of the location and circumstances of the death. Therefore, the investigator will attempt to learn as much as possible about the events leading up to the death, even the very moment that the death occurred.
The Centers for Disease Control and Prevention (CDC) have developed guidelines for death scene investigation of a sudden, unexplained infant death (CDC, 1996). Local jurisdictions may use these guidelines or develop their own protocols for investigating sudden unexpected infant death.
Investigators will interview the parent or other individual who was caring for the child at the time of the death, as well as any other family members or adults who were present at the time of the death or before the death occurred. The investigator will ask openended,
neutral questions such as, "Can you tell me what happened?" "How old was the baby?" "What did the baby weigh?" "What time was the baby put to bed?" "When did the baby fall asleep?" "Who last saw the baby alive?" "Who discovered the baby, and what did that person do?" "What position was the baby in when he/she was found?" "Were there covers over the baby's head?" "Was CPR attempted?" "Did the baby share a bed with anyone else?" "What was the general health of the baby?" "Had the baby been ill recently?"
The individual investigating the death will take notes about the appearance of the room where the death occurred; condition and characteristics of the crib or sleeping environment; objects, if any, in the crib; medications at the death scene; and any unusual or dangerous items in the room, such as sharp objects or plastic bags. The investigator may make notes about the behavior of those present at the death scene. The investigator will also photograph the death scene and record the temperature of the room. It is likely that investigators will collect the infant's bedding (e.g., sheets, blankets, etc.), any objects in the crib (e.g., toys or bottles), or any unusual or dangerous items found near the death scene.
An autopsy provides evidence of the cause of death through microscopic examination of tissue samples and examination of the body and vital organs. An autopsy is particularly important when a SIDS death is suspected because a definitive diagnosis cannot be made without a thorough postmortem examination. It is estimated that in 15 percent of cases suspected to be SIDS, the autopsy identifies another cause of death, such as a disease or genetic disorder, as well as unintentional injury or unnatural death (Valdes-Dapena, 1995). Also, if a cause (or causes) of SIDS is ever to be uncovered, it is likely that the cause will be detected from evidence gathered from a thorough pathological examination.
An autopsy may help parents and other caregivers deal with the death. According to noted authority Marie Valdes-Dapena, M.D., parents whose child has died need to know why the death occurred; they need to be reassured that their baby's death could neither have been predicted nor prevented (Valdes-Dapena, 1995). Moreover, an autopsy leading to a diagnosis of SIDS will help remove the parents (or caregiver) from potential suspicion of wrongdoing by the legal system and by society in general.
Parents are usually anxious to consult with the pathologist after the autopsy. Discussing the autopsy results often helps most parents accept the reality of their infant's death. The pathologist reviews the autopsy results, explaining in terms the parents can understand how these findings point to a determination of cause of death. The pathologist should also take the time to answer parents' questions, responding with "compassion, understanding, and respect for the parents' dignity and grief" (Valdes-Dapena, 1995).
3) Review of the Infant's and Family's Medical Histories
A comprehensive medical history is essential for a SIDS diagnosis. Along with a death scene investigation and an autopsy, a careful review of the infant's and family's history of disease, previous illnesses, accidents, and behaviors often helps to corroborate what is detected from the death scene investigation and the autopsy.
What is the best way to reduce my baby’s risk for SIDS?
Placing your baby on his or her back to sleep for every sleep time is the best way to reduce the risk of SIDS.
Will my baby choke if placed on the back to sleep?
No. Healthy babies naturally swallow or cough up fluids—it’s a reflex all people have. Babies might actually clear such fluids better when on their backs.
What if my baby rolls onto the stomach on his or her own during sleep? Do I need to put my baby in the back sleep position again if this happens?
No. Rolling over is an important and natural part of your baby’s growth. Most babies start rolling over on their own around 4 to 6 months of age. If your baby rolls over on his or her own during sleep, you do not need to turn the baby over onto his or her back. The important thing is that the baby start off every sleep time on his or her back to reduce the risk of SIDS, and that there is no soft, loose bedding in the baby’s sleep area.
What are the risk factors?
Although sleep position, smoke exposure, overheating, and infant bedding have been identified as risk factors for SIDS, researchers have identified a number of other factors that may put an infant at increased risk for SIDS.
Infant Care Practices and SIDS Risk Reduction
Several studies have examined various environmental influences or child-rearing practices that may help protect an infant from SIDS (Valdes-Dapena, 1995; Hoffman et al., 1996; NICHD, 2000). It is important to point out, however, that these factors, in and of themselves, are not reliable in predicting how, when, why, or if SIDS will occur.
For example, although researchers conclude that breastfeeding is beneficial, there is no clear-cut link between breastfeeding and reduced risk of SIDS. Other studies have found a lower rate of SIDS among infants who used pacifiers compared with infants who did not use pacifiers. Although results of these studies tend to be consistent, there is still no evidence that pacifier use prevents SIDS(AAP, 2000).
Maternal Risk Factors
Still other risk factors, called maternal risk factors, are associated with how the mother's behavior and health affect the infant before and after birth.
Maternal risk factors include:
- age less than 20 at first pregnancy
- a short interval between pregnancies
- late or no prenatal care
- smoking during and/or after pregnancy
- placental abnormalities
- low weight gain during pregnancy
- alcohol and substance abuse
- history of sexually transmitted disease or urinary tract infection
What do current research findings and theories indicate?
Most scientists now believe that babies who die of SIDS are born with one or more conditions that make them especially vulnerable to the internal and external stresses that occur in the life of any infant. Currently, many researchers argue that the clue to finding the cause(s) of SIDS lies in a further understanding of the development and functions of the brain and nervous system of SIDS infants.
These scientists theorize that some babies at risk for SIDS have defects in those parts of the nervous system that control breathing and heart rate. Maturation of the brainstem may be delayed in SIDS infants. Myelin, a fatty substance that facilitates nerve signal transmission, appears to develop more slowly in SIDS infants than in other babies.
"The detection of subtle abnormalities in SIDS brains indicates that not all SIDS infants are 'normal' despite their lack of clinical abnormalities. The occurrence of brain abnormalities supports the concept that a vulnerable, and not a normal, infant is at risk for SIDS. The idea of a vulnerable infant forms a key part of a triple-risk model for the pathogenesis of SIDS" (Filiano and Kinney, 1994).
The Triple-Risk Model
Pathology studies of SIDS infants support the view that these infants possess underlying vulnerabilities that put them at risk for sudden death, a concept advanced by the triple-risk model in describing the sequence of events leading to the death of an infant. A number of scientists are currently applying this model in their search for a cause(s) of SIDS.
- Vulnerable Infant. The first key element of the triple-risk model depicts an infant with an underlying defect or abnormality, which makes the baby vulnerable. In this model, certain athophysiological factors (e.g., defects in the parts of the brain that control respiration or heart rate, and that occur during early life) explain vulnerability to sudden infant death.
- Critical Developmental Period. The second element in the triple-risk model refers to the infant's first 6 months of life. During this critical developmental period, rapid growth phases occur and changes in homeostatic controls take place. These changes may be evident (e.g., sleeping and waking patterns), or they may be more subtle (e.g., variations in breathing, heart rate, blood pressure, and body temperature). It may be that some of these changes may temporarily or periodically destabilize the infant's internal systems.
- Outside Stressor(s). The third element of this model involves outside stressors. These may include environmental factors (e.g., exposure to tobacco smoke, overheating, or prone sleep position) or an upper respiratory infection that most babies can experience and survive, but that an already-vulnerable infant may not be able to overcome. In and of themselves, these stressors do not cause infant deaths, but in a vulnerable infant, "may tip the balance against an infant's chances of survival" (Filiano and Kinney, 1994). According to this model, all three elements must interact for a sudden infant death to occur—the baby's vulnerability is undetected until the infant enters the critical developmental period and is exposed to an outside stressor or stressors.
Brain Abnormalities in SIDS Infants
A team of researchers funded by the National Institute of Child Health and Human Development (NICHD) has discovered that infants who die of SIDS may have abnormalities in several parts of the brainstem. This finding builds on the results of an earlier study that identified abnormalities in the region of the brain known as the arcuate nucleus in babies who died of SIDS.
In the NICHD study, SIDS infants were found to have decreased binding of serotonin in the nucleus raphe obscurus, a brain structure linked to the arcuate nucleus, as well as four other brain regions. These areas of the brain are thought to play a crucial role in regulating breathing, heart beat, body temperature, and arousal (Panigrahy et al., 2000).
What is the Back to Sleep campaign?
About SIDS deaths in child care settings?
Helping Baby "Back to Sleep"
Safe Sleep for Your Baby
• African American
• American Indian
What Does a Safe Sleep Environment Look Like?
Safe Sleep for Your Grandbaby
Crib Safety Tips
Safe and Asleep in a Crib of Their Own
Baby Safety Basics