Sudden Unexplained Death In Childhood (SUDC): Must-know information

Sudden Unexplained Death In Childhood (SUDC): Must-know information

Sudden unexplained death of a child cannot be stopped. But it can be prevented. Read on to know more about this mysterious phenomenon that is increasingly affecting young children.

When Marissa Wong, 32, received a call from her two-year-old daughter’s daycare, she thought it would be routine. Little did she expect that they would call to inform her about the sudden unexplained death of a child she loved with all her heart — her darling little girl Candice.  

Even though the daycare authorities rushed Candice to a hospital, the doctors couldn’t save her.

She wasn’t sick. Candice was a healthy child. She didn’t suffer from any illness, nor did she have any childhood infections. Then why did she die? 

The doctors told Wong that Candice just suddenly fell on the floor and collapsed. They explained that she died of what is called Sudden Unexplained Death of a Child or Sudden Unexplained Death in Childhood (SUDC).

What is SUDC? It is the lesser-known cousin of Sudden Infant Death Syndrome (SIDS), which the Centers for Disease Control and Prevention (CDC) defines as “the sudden death of an infant less than one year of age that cannot be explained after a thorough investigation is conducted, including a complete autopsy, examination of the death scene, and review of the clinical history.”

What many parents don’t know is that even older children can die suddenly and from no apparent cause. 

Sudden Unexplained Death of a Child: everything parents must know 

Reportedly, SUDC affects about 1.4 deaths per 100,000 children globally. As per the National Organisation for Rare Disorders (NORD), here are some shocking statistics:

  • Almost 60 percent toddlers between the ages of one and four who die, die of SUDC.
  • It doesn’t affect one particular ethnic group more than others. 
  • Nearly 90 percent of those affected by SUDC are born full-term and healthy.
  • Almost half of those affected by SUDC were first born kids.

So what is this mysterious and silent child killer? 

What is Sudden Unexplained Death of a Child? 

This silent killer usually affects children above the age of 12 months. And, the exact cause of death as the name suggests, is difficult to explain.
In fact, even after doctors perform a thorough examination, including the study of the child’s medical history and genetics, they cannot determine the reason for the death. 

Presently, experts are trying to understand more about SUDC. And in their studies they found several patterns regarding the bodies of children who died of SUDC.

As per WebMD, here is what they found:

  • Children who died placed supine (chest facing upwards towards the ceiling): 10 percent
  • Those who died lying on the side: 2 percent
  • Kids found prone position (chest down to the floor and back facing upwards): 3 percent
  • Kids found with their faces positioned downwards: 10 percent
  • Those found with their faces positioned on the side: 8 percent
  • Those co-sleeping with parents/guardians: 3 percent
  • Incidents of children who were found with their bodies sweating: 1 percent
sudden unexplained death of a child

Almost 60 percent of toddlers between the ages of one and four who die, die of SUDC. | Image courtesy: Pixabay

In addition to this information, the NORD found that almost all children with SUDC were supposedly sleeping before they became unresponsive. 


You might wonder, if it is “unexplained” then how can there be a cause? While it is difficult to exact the cause of SUDC, there are a few possibilities. 

NORD lists a few possible reasons for sudden unexplained death in a child. 

  • Some children have a family history of febrile seizures. These are convulsions that spike the child’s body temperature and are often due to an infection. So if the doctors find that any member of the child’s family suffers from febrile seizures, they relate it to SUDC in the child. 
  • Sometimes epilepsy could be the cause. In this case, the death is unexpected and sudden. And postmortem reports do not indicate an anatomical or toxicological reason.
  • In other cases, a tonic-clonic seizure can lead to SUDC. These are terminal convulsions where the muscles stiffen and the child may groan or cry and has jerky movements. It usually lasts for one to three minutes, but if it lasts for more than five minutes, the child should immediately be taken to a hospital.  
  • Another probable cause is an underdeveloped brain. If there are any subtle abnormalities in the brain, it can lead to SUDC.

It has to be noted that these are yet to be proved as the exact cause of SUDC. These are only suspected causes. But if there is a family history of any of these conditions, it’s best to get your child checked with a specialist at least once, for peace of mind. 


On the basis of the probable causes of sudden unexplained death of a child, NORD suggests that one must keep an eye out for signs of seizures. In most SUDC cases, children are healthy and do not necessarily exhibit any symptoms. 

NORD stated on their website, “Most were born as full-term singletons and their development was considered normal. Children were in their state of usual good health prior to death, or had mild symptoms of illness such as cold symptoms or fever. Some children with SUDC had a history of febrile seizures, or a family history of febrile seizures.” 

Dr. Henry Krous, former director of the San Diego SUDC research project (2001 to 2012) also explains, “At the present time, there is no way to prevent SUDC as its cause(s) is not known. It is hoped that future research will identify means by which SUDC can be prevented. If and when risk factors are identified, such as prone sleep position for SIDS, then one might anticipate reduction in the risk of SUDC.”

Related complications and symptoms

These symptoms of the following illnesses can sometimes be similar to the sudden unexplained death of a child. So you should watch out for these as well. The NORD explains the three illnesses as follows: 

1. Sudden Unexpected Death in Epilepsy (SUDEP)

This is a non-traumatic and sudden death of a child or an adult with epilepsy. In this case, the autopsy doesn’t reveal any anatomical or toxicological cause of death.

sudden unexplained death of a child

You should monitor children with abnormal electrical heart rhythms and take them for regular health checkups. | Image courtesy: Pixabay

It could happen to a healthy child as well, and death comes almost immediately. NORD explains, “Each year, more than 1 out of 1,000 people with epilepsy die from SUDEP. However, it occurs more frequently in people whose seizures are poorly controlled.” 

The causes for SUDEP could be the following:

  • Obstruction of airway, especially if the child is lying face down on the bed
  • Cessation of breathing
  • Filling of fluid in the lungs post a seizure
  • Those with abnormal electrical heart rhythms

2. Sudden arrhythmia death syndromes (SADS)

These are genetic heart conditions and usually occur in young children and even young adults. The good news is that doctors can treat this condition, and so they can also prevent death.  

Since SADS is caused by genetics, it is usually passed down from a parent to a child. As per NORD, “every child of the affected parent has a 50 percent chance of inheriting the condition.” 

But this illness also has specific symptoms that you must watch out for. 

  • Family history of SADS. Keep tabs on family members diagnosed with SADS as well as instances of SUDC affected children in the family. 
  • Fainting. If you notice that your child faints a lot, or if there is somebody in the family who does, you should report this to your doctor. It usually occurs when the heart’s electrical system stops working properly. This causes the heart to beat with an abnormal rhythm. 

3. Metabolic errors

The third related complication that can cause, or is related to the sudden unexplained death of a child, is an inborn metabolic error. It is a rare genetic disorder. Here, the body is unable to turn food into energy properly.

As NORD explains, “The disorders are usually caused by defects in specific proteins (enzymes) that help break down food into usable energy.”


Sudden Unexplained Death In Childhood (SUDC): Must-know information

Image source: iStock

Unfortunately, due to its sudden nature, preventing the sudden unexplained death of a child is almost impossible. However, Dr Krous says there is hope because parents can take preventive measures. 

“Follow optimal pediatric care recommendations, including attending well child visits, maintaining current vaccinations, and obtaining appropriate health care when clinically indicated,” Krous advises.

When very little is known about the sudden unexplained death of a child, what you need to know is that it exists. You still need to be extra vigilant about your child’s health and behaviour even as he grow older. 

It’s always better to be safe than sorry—equip yourself with relevant information about this phenomenon. 

Sources: Babble, SUDC, Rare Diseases, NCBI, Centres for Disease Control and Prevention  

ALSO READ: 7 serious childhood illnesses that seem harmless at the onset

Got a parenting concern? Read articles or ask away and get instant answers on our app. Download theAsianparent Community on iOS or Android now!

Written by

Deepshikha Punj

app info
get app banner