SIDS safe mattress – bursting the bubble

Numu-roo is the safest mattress for little ones.

We know that, but what does this actually mean for you?

We keep getting asked if Numu-roo is “SIDS approved” or “SIDS safe” so we thought we would talk about the “monster” in the room and how Numu-roo can help to battle it.

Table of content

What is SIDS

SIDS (Sudden Infant Death Syndrome) is the leading cause of death under the age of 1 and is one of the main concerns for both new and experienced parents.

SIDS is frightening because it remains unpredictable despite years of research. We don’t know what causes SIDS but we do know that there are environmental factors that increase the chances of it happening.

This is much like (sorry, I'm going to mention another monster) cancer. We don’t
know how it happens and we can’t prevent it, but we know that a healthy lifestyle can reduce our chances of getting it 1.

We know that SIDS happens mostly during sleep and is associated with vulnerability to environmental stresses 1,2. Increased vulnerability can be due to illness preterm or exposure to tobacco or other substances during pregnancy 3.

Increased vulnerability can also be due to other physiological factors we don’t understand, so even a seemingly healthy baby can be vulnerable, we can’t control this, but we can control environmental stresses which our baby encounters during sleep and affect her temperature and breathing 1,2.

Can we prevent SIDS?

OK, so what can we do? Research has identified a long list of environmental factors which can reduce statistics of SIDS. First and most importantly, sleep baby on his or her back. 

Back sleep

Back sleep was found important as early as 1944 when one study reported that 68% babies who died of sudden suffocation were put to sleep on their tummyor side 4.

Since then, multiple studies have shown the direct correlation between increased awareness to back sleep and reduction in SIDS cases throughout the years, though the benefits are not fully understood 5. One theory is that back sleep positioning reduces the risk of baby’s head being pressed against the mattress and reduced airflow 6

Another hypothesis is that back sleep might decrease chances of aspiration of regurgitation 7.

It is also recognised that sleep positioning might mechanically affect how your baby’s body regulates breathing, temperature and arousal control 8,9 . Most likely the benefits for sleeping babies on their back are a combination of all of the above so, in any scenario, always, please... sleep your baby on his back.

sids risk factors

Another recommendation is to sleep baby in his own bed in the parent’s room. The benefit of room sharing, apart from facilitating breastfeeding, a beneficial factor on its own 10, is assumed to be the increased level of monitoring and awareness of parents when baby is sleeping nearby 11,12.

There is a difficult time period around the age of three months when babies begin to turn on to their tummies by themselves. This is a worrisome phase for many
parents that are not sure what to do, follow the guidelines and flip baby on his back or let them be? Especially if they know that their baby does not have enough body control yet to turn to his back if he wanted to. Here, the recommendation is to help baby to his back if you notice this happened but that there is no need to wake up at night especially to do this.

Why? It’s a compromise.

Back sleep is still the safest position for babies this age, but parents need their sleep as well. In these cases there is a great benefit for using the Numu- roo mattress as it does not obstruct airflow even when your baby’s face is pressed into it 13. This makes sleeping easier for parents and eliminates the worry to wake up frequently at night to check on their baby.

Keep little face uncovered

Another important guideline is to put your baby to sleep with his face uncovered. Furthermore, we need to make sure that there are no loose or soft items in his surroundings that could potentially block or reduce airflow 14,15. Such items can be soft or loose bedding, beanies, cot bumpers, teething necklaces or security toys.

It has not occurred to the community yet that the mattress itself is the bulkiest item in our babies sleep environment. No matter what it is filled with, foam, springs or other material, it is still a few centimetres thick object in our baby’s bed that allows minimal to no airflow, which means that if baby is breathing into the mattress, the CO2 he exhales stays around so that the inhaled air becomes richer in CO2 and poorer in oxygen 6,16. This is one of the causes for suffocation. 

The Numu-roo mattresshas been shown to allow maximal air circulation and
prevent CO2 accumulation 13 so if you eliminated the doona, the cot bumper, the beanie, the pillow and the teddy, why not complete the job and eliminate the mattress?

Breathing mattress

Firm, flat, clean mattress

A soft mattress or mattress cover can potentially cover, completely or partially, baby’s airway. Any sleeping surface that has not passed a firmness test for cot mattresses should be considered unsafe (unfortunately there is no firmness standard for bassinet mattresses yet in Australia). This includes cushioned seating such as sofas, adult mattresses such as your own bed, prams and so on.

Yes, your baby might be snug and sleep “better” in one of these, but this might be due to reduced arousal control - reduced ability to wake up when something is wrong - which is also one of the risk factors 8,9.

In summary, sleep baby on a cot mattress that is the right size for the cot, is firm and clean and in good condition.

Numu-roo did not only pass the firmness test and can be custom made to fit any cot size, but because of its design, it is remarkably preserved throughout the years and can easily be cleaned more thoroughly than any other mattress.

The cleanliness of the mattress eliminates dust mites, bacteria and mould that accumulate in regular mattresses over the years and that can trigger allergies or
infections that have been suggested to indirectly contribute to SIDS 17,18.


Reduce over heating

Soft sleeping surfaces are also warmer, and this brings us to the issue of temperature regulation which has been tied to SIDS risk 19-21.


Babies are less capable of regulating their own temperature and rely greatly on their environment. For this reason, dress your baby in clothing that’s warm, but not hot, refrain from soft bedding and from covering baby’s head with a beanie when sleeping. (We wrote a case study about baby sweating at night)

Again, regular mattresses are bulky and are major heat

Would you cover your baby with a 10cm thick doona?

Regular mattresses are actually doing the same job but from underneath your baby, by blocking air flow they are insulating and trapping the heat that is emitted by your baby.

The airflow achieved with Numu-roo allows your baby to better regulate his body temperature and prevents overheating and sweating 13 . (We wrote about 10 things you can do to prevent baby overheating )

numu roo mattress



SIDS safe mattress?

As SIDS is not fully understood and is dependent on so many physiological and
environmental factors, it is not possible to give any product a “SIDS safe” stamp.

There is no product that can promise using it will prevent SIDS. However, some products, like the Numu-roo, are better than others at managing the risk factors we are familiar with.

Click here to see Numu-roo's cot mattress and here for bassinet mattress

If you found this blog post of value, and if you are in your Nursery planning, also look at our "we now know better" blog post - link - "Safer sleep, because we now know better"



 (Written by a Scientist, PhD Biology and a mother of three)



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