baby with teddy and furry blanket which is not recommended

How to reduce the risk of SIDS

Sudden Infant Death Syndrome (SIDS) is every parent’s worst nightmare. SIDS  is the sudden, unexplained death of a baby younger than 12 months old that doesn’t have an explanation even after a thorough investigation.

Not everything is known about how Sudden Infant Death Syndrome (SIDS) works, but the good news is that it is a lot less common than it used to be and there is a fairly good understanding of the risk factors involved. 

Reduced rates of SIDS

In the UK the rate of SIDS has reduced by 85% since 1991 when the Back to Sleep campaign was launched. Similarly, in the USA, great progress has been made with a 63% reduction in that time. The focus of the Back to Sleep campaign was placing baby on her back to sleep rather than the prone position. The Lullaby Trust say that a baby put to sleep on their front is 6 times more at risk of SIDS than one on their back. The rate of occurrence of SIDS in the UK is 0.3 deaths per 1,000 live births.

What causes SIDS?

Scientists are still searching for the definitive answer to this question. The latest thinking suggests that is a combination of three factors, all of which must be present: 

  • A vulnerable infant. An underlying defect or brain abnormality in the areas that control respiration or heart rate or genetic mutations
  • The baby is in a critical development period that can temporarily destabilise their systems
  • Outside stressors that can’t be overcome due to the other two factors

The reason why there has been a great reduction in the rate of SIDS is because of the improved behaviours in terms of the baby’s sleep environment. 

What are the Outside Stressors that increase the risk of SIDS?

  • Sleeping on their back
  • Soft bedding (which can increase the risk of suffocation)
  • Loose bedding (don’t use a pillow, quilt, extra bedding, stuffed toys)
  • Overheating (don’t use too much clothing or blankets, make sure the temperature in the room isn’t too hot. More babies die of SIDS in winter, possibly due to too many blankets etc.)
  • Smoking during pregnancy and in the baby’s environment
  • Bed sharing (a mother sleeping with baby can lead to suffocation, entrapment or injury) and this is exacerbated if the mother smokes, has taken alcohol or is fatigued; the baby is covered by a quilt; or there are multiple bed-sharers

Bacterial Toxins, Baby Mattresses and SIDS

 A 1999 study in Edinburgh found Staphylococcus aureus in 86% of SIDS babies versus 57% in the non-SIDS babies. Staphylococcus aureus are common micro-organisms and their toxins are very powerful. 

So where do the bacterial toxins come from that give rise to this? The mattress is an obvious candidate. A 2008 study showed that infant use of cot mattresses with exposed PU foam leads to accumulation of proteins within the PU, which can promote bacterial growth. This leads us to conclude that if you are using a baby mattress it should have a waterproof membrane between the baby and the core of the mattress, particularly at the infant head area. The difficulty with this can be that many waterproof covers can lead to baby overheating as they are not skin breathable. And you should avoid foam mattresses. 

This is why the Pure Zees baby mattress offers a comprehensive solution. It doesn’t use foam with it's harmful flame retardant chemicals, nor does it use dubious dust mite and bacteria killing chemicals. It is completely waterproof, at the infant head position and everywhere else, without the need for a separate waterproof cover. Pure Zees unique membrane blocks the passage of saliva, vomit, faeces etc into the core of the mattress where they could ferment and give rise to toxic bacteria. And yet, this mattress membrane is also skin breathable and very comfortable for baby. Unlike many baby mattresses on the market this "skin breathable" fact has actually been tested and proven and not just an empty marketing claim.  

Guidelines for buying a cot/crib mattress

When considering your baby mattress

  • Choose a firm mattress
  • Make Sure the Cover is Waterproof While Skin Breathable
  • Make Sure the Cover is Impermeable to Dust Mites
  • Flippable - lightweight so that it is easy to turn regularly
  • Easy to Clean
  • Watch out for Chemicals

For more information on the above cot mattress consideration factors have a look at one of our previous healthier nursery room blogs "6 Things to Look For when Buying a Cot Mattress"


We don’t advocate reusing a baby mattress that another baby has used, unless it is a Pure Zees mattress (read why here).

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