Frequently Asked Questions

General Questions

What is SUDC?

Sudden Unexplained Death in Childhood (SUDC) is a category of death in children between the ages of 1 and 18 years that remains unexplained after a thorough investigation, including an autopsy.1. Most often, a seemingly healthy child goes to sleep and never wakes up 2,3.

What is the SUDC Foundation?

The SUDC Foundation is the only organization worldwide whose purpose is to raise awareness, fund research, and serve those affected SUDC. The SUDC Foundation provides all services at no cost to families.

Is SUDC something new?

SUDC is not new but is believed to be rare, with our most conservative estimates being about one in every 100,000 children. Every year, at least 400 children are lost to undetermined causes in the U.S. It is most common in young children and is the fifth leading category of death among children ages 1 to 4 years.

In order to better understand how often SUDC truly occurs, we need population-based studies where we examine cases that reflect the gender and ethnic diversity of the general population. The Sudden Unexplained Death in Childhood Registry and Research Collaborative (SUDCRRC) of NYU Langone Health, which is supported in part from funding from the SUDC Foundation, has the largest database of SUDC victims to date.

Why haven't I heard of SUDC before?

SUDC was first defined in 2005. Although it was not new, this was the first public recognition of unexplained childhood deaths since the redefinition of SIDS in 1989, which excluded children older than 12 months. SUDC has received little attention from public health officials. Current awareness efforts are driven by the SUDC Foundation. Unfortunately, most people first learn of SUDC after a tragedy in their own child, their patient or someone they know. Raising awareness of SUDC is at the core of the work of the SUDC Foundation.

What causes SUDC?

At this time, we do not know what causes SUDC. Sudden Unexplained Death in Childhood (SUDC) is a category of death, not a cause of death, in children between the ages of 1 and 18 that remains unexplained after a thorough investigation, including an autopsy. It is likely that SUDC does not have a single cause, but many causes, and is an umbrella term to describe these deaths that have not been specifically determined.

Can SUDC be predicted or prevented?

No. At this time, we do not know what causes SUDC, how to predict it or how to prevent it. Through research, we strive to discover the risk factors and underlying causes of SUDC that will lead to its prevention. In the meantime, the SUDC Foundation recommends all families follow guidelines provided by the American Academy of Pediatrics in regards to attending regular child wellness visits, maintaining current vaccinations and seeking medical care when needed.

Is SUDC genetic?

Although rare, we know there are some genetic causes of sudden death that are not discovered by standard autopsy investigations. This is one of the many reasons that we advocate for comprehensive investigations, including genetic testing, for all sudden unexplained deaths, as well as screening of family members and DNA banking. Research will improve our understanding of the specific genetic variations that may contribute to some cases of sudden death that currently fall under SUDC. This could lead to the ability to screen at-risk children and help them receive appropriate medical care. 

What if a specific cause of death is identified for my child? Can the SUDC Foundation still help me?

The SUDC Foundation wants to help all families find accurate causes of death, and about 20% of our families do. The SUDC Foundation may be able to assist families with obtaining a second opinion of the child’s cause of death which may help with their grief and making future decision for their family. Regardless, the SUDC Foundation’s family services are available for all families grieving the sudden, unexpected death of a child (1-18 years). And all services are provided at no cost to the family.

Is SUDC like Sudden Infant Death Syndrome (SIDS) and/or Sudden Unexplained Infant Death (SUID)?

Terminology by acronym alone can be confusing dependent on location. Sudden Unexpected Infant Death (SUID), as used commonly by public health officials in the United States, refers to the combined rate of the three most frequent types of sudden unexpected deaths in infancy: sudden infant death syndrome (SIDS), accidental suffocation in a sleeping environment and other deaths from unknown causes.4

SUID may also be used by medical examiners and coroners as a final death certification: sudden un-explained infant death. SIDS is “the sudden, unexplained death of an infant younger than 1 year old,” (Eunice Kennedy Shriver National Institute of Child Health and Human Development).

In the United Kingdom, where the term “infant” can refer to children under 24 months, the defini-tion of SIDS differs by age, and describes it as the sudden, unexpected and unexplained death of an apparently healthy baby under 24 months of age [NHS, Department of Health and Social Care (DHSC).] 

SUDC is similar to SUID in that it: 

• occurs in otherwise healthy children, 
• most often during sleep, 
• and has no known explanation. 

There may be other similarities, but research into SUDC is in its early stages and more is needed to better understand how similar or different the underlying causes are. The biggest difference we know is that a child’s death may be certified as SIDS or SUID in the U.S. if the child is less than 12 months of age. A child’s death may be certified as SUDC if he or she is over 1 year old, but under the age of 18.


1. Krous  HF, Chadwick  AE, Crandall  L, Nadeau-Manning  JM.  Sudden unexpected death in childhood: a report of 50 cases.  Pediatr Dev Pathol. 2005;8(3):307-319

2. Crandall LG, Lee JH, Stainman R, Friedman D, Devinsky O. Potential Role of Febrile Seizures and Other Risk Factors Associated With Sudden Deaths in Children. JAMA Netw Open. Published online April 26, 20192(4):e192739.

3. McGarvey A, O’Regan M, Cryan J, et al. Sudden unexplained death in childhood (1-4 years) in Ireland: an epidemiological profile and comparison with SIDS. Arch Dis Child. 2012;97(8):692-697.

4. Centers for Disease Control and Prevention; Division of Reproductive Health, National Center for Chronic Disease Prevention and Health Promotion,, 2018.

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