Are There Warning Signs of SIDS?

Warning Signs of SIDS

Are there warning signs of SIDS?

SIDS (Sudden Infant Death Syndrome) has no symptoms or warning signs. Babies who die of SIDS seem healthy and normal.  They show no signs of struggle. 

Diagnosis of Exclusion

A baby is determined to have died from SIDS if no cause of death can be identified following a death scene investigation, an autopsy, and a review of the clinical history of the infant.   

SIDS is a diagnosis of exclusion, meaning he cause of death is labeled as SIDS only after all other causes have been excluded.

Carbon Dioxide Rebreathing

While there are no warning signs of SIDS and the cause of SIDS is unknown, many clinicians and researchers believe that SIDS is associated with problems in the ability of the baby to arouse from sleep to detect low levels of fresh oxygen.  Rebreathing carbon dioxide leads to hypoxia, and eventually death. 

SIDS is a big concern of most parents because there are no warning signs of SIDS.

Face Down Sleeping

When a baby is sleeping face down, they can re-breathe exhaled carbon dioxide if sleeping on a fiber filled mattress or pad.  Babies who sleep on their tummy with their hand or arm close to their face can also rebreathe. 

Normally, rising carbon dioxide levels activate nerve cells in the brain stem, which stimulate the brain’s respiratory and arousal centers. The baby then wakes up, turns his head, and breathes faster to get more oxygen. SIDS babies fail to rouse to get fresh oxygen. 

Rebreathing of carbon dioxide eventually suppresses their need to breathe and they never wake.  SIDS babies simply pass in their sleep with no warning signs.

Triple-Risk Model

The “Triple-Risk Model” for SIDS has been proposed to explain how SIDS occurs, and why there are no warning signs of SIDS. The model holds that SIDS occurs when three conditions exist simultaneously:

  • the infant has an underlying (e.g., brainstem) abnormality that makes him unable to respond to low oxygen or high carbon dioxide blood levels
  • the infant is exposed to a triggering event such as sleeping face down on its tummy
  • these events occur during a vulnerable stage in the infant’s development, i.e., the first 6 months of life

The underlying abnormality is low serotonin levels in the brain stem.  We currently have no way to test infants to find out which ones do or do not have low serotonin levels.  The vulnerable stage in the infant’s development is believed to be a rapid brain growth phase.   

Conception to birth is a human’s most rapid growth phase and birth to 1 year is the second.   Infant’s internal organs are growing quickly.  Unfortunately, we have no way to determine when an infant is growing through a rapid brain growth phase, so all infants remain vulnerable.    

The SIDS Triple Risk Model helps explain why there are no external warning signs for SIDS.

Risk Reduction

There is currently no way to “prevent” SIDS from occurring; however, you can vastly reduce your baby’s risk of SIDS by:

  • putting your baby to sleep on his back
  • keeping blankets, pillows, stuffed animals, bumpers, and other stuffed objects out of his crib
  • overheating your baby or his room when he sleeps
  • not smoking when you are pregnant and not allowing anyone to smoke around your baby
  • breastfeeding
  • Using an air permeable/breathe-through crib mattress that does not trap carbon dioxide even if your baby is sleeping face down or on their tummy

Over 3,400 infant deaths are classified as SIDS each year in the U.S., and there are no warning signs for these SIDS deaths.  The best a parent can do is make good choices to keep their sleeping baby safe. 

The best way to keep your baby safe is to make sure when you put your baby to sleep for nap or night, you do everything possible to make sure there is nothing in your baby’s crib that can cause the build up of carbon dioxide should your baby roll to their tummy. 

The creators of the first air permeable/breathe-through crib mattress found out the hard way what can happen when an infant rolls over on while sleeping on a fiber filled crib mattress.


Since there are no warning signs for SIDS, all infants remain at risk.  The SafeSleep® Breathe-Through Crib Mattress  has given over 80,000 parents piece of mind.  Why? 

The SafeSleep®”Completely” Breathe-through Crib Mattress has been tested for carbon dioxide retention and has a ten-fold decrease in carbon dioxide retention when compared to a fiberfill mattress with a tight-fitting sheet. 

It takes 2 minutes for carbon dioxide to dissipate on a firm crib mattress with a tight sheet; it takes less than 1/2 a second for it to dissipate on the SafeSleep® Crib Mattress. 

An infant takes a breath every 1-2 seconds, meaning the carbon dioxide (poisonous gasses) on the SafeSleep® Breathe-Through mattress would be gone before the infant takes their next breath of air – even if face straight down

The hollow frame below the open weave top layer is filled with nothing but constantly circulating, pure organic air, creating the ideal oxygen rich sleep environment for your baby.  

Learn more about how to prevent SIDS.

Related Topics

Skip to content