Baby Sleep
How Firm Should A Crib Mattress Be

How Firm Should A Crib Mattress Be

What is the ideal firmness for a crib mattress?
You can’t compare what’s pleasant (and safe) for an adult to what’s comfortable (and safe) for a newborn when it comes to crib mattresses. When it comes to newborns, a firmer crib mattress is preferable.

A firm crib mattress is required to support a baby’s skeleton, protect the baby’s safety (and avoid asphyxia), and many other things. Continue reading to understand why a crib mattress is crucial and how to know whether one is firm enough.

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Firm Crib Mattress Really is Necessary for Your Baby

If you’ve spent any time reading crib mattress reviews online, you’ve undoubtedly come across one of the most common complaints from parents, grandparents, and other people in charge of purchasing a newborn crib mattress:

As solid as a rock! I understand that newborns need a firm crib mattress, but it shouldn’t feel like they’re sleeping on a rock!

I’d let my kid sleep on our wooden floor if I wanted a crib mattress this firm.

And, of course…

It was simply far too stiff. This is not a mattress I would sleep on. It’s impossible for me to envision my newborn sleeping on it. It doesn’t appear to be a pleasant situation.

We understand where these parents and grandparents are coming from, to be honest. You want nothing but the best for your child. And that includes helping them feel at ease when they go off to sleep.

All parents want their children to have a good night’s sleep. It would seem obvious that a too-firm mattress would be uncomfortable for the infant and result in lower sleep quality, right?

Wrong. Here’s the deal: Adults and babies are not the same. Adults can – and should – do a lot of things that babies can’t or shouldn’t. Sleeping on a comfortable mattress is part of that.

You can’t compare what’s pleasant (and safe) for an adult to what’s comfortable (and safe) for a newborn when it comes to crib mattresses.

It’s simply that they’re different.

When it comes to newborns, a firmer crib mattress is preferable.

Importance Firm Baby Mattress 

Skeletal Support

Firm crib mattresses provide the support that newborns’ bones and skeletons require as they develop and mature from a developmental standpoint.

Adults have 206 bones, whereas infants have about 300. Some of a baby’s bones fuse together between birth and the age of 25, which is why adults have fewer bones than newborns.

Babies not only have more bones than adults, but their bones are also more softer. In reality, some of the bones in a baby’s body aren’t composed of bone yet. Instead, they’re fully (or partially) composed of soft, malleable cartilage. Bone replaces cartilage as the infant grows.

The skeleton of a newborn is considerably different from that of an adult, and it requires greater support. The spines of babies require greater support than the spines of adults. And the bones of newborns require greater support than the bones of adults.

Soft crib mattresses do not provide this support, but firm crib mattresses do.

Safety

A firm cot mattress is also necessary for a baby’s safety. SIDS is more common in soft crib mattresses than in medium or hard crib mattresses.

Soft crib mattresses and the risk of suffocation are the same.

Soft mattresses can adapt to a baby’s face if he or she is put to sleep on his or her stomach or rolls onto his or her stomach while sleeping. Suffocation is more likely as a result of this.

In the framework of the so-called rebreathing idea, soft mattresses may potentially be hazardous. Soft bedding and mattresses, according to this idea, enhance the chance of a baby’s expelled air becoming caught around its face, forcing it to re-breathe its own exhaled breath (carbon dioxide).

It’s worth noting that there are now “no physiologic data from children who perished” to back up the rebreathing idea. However, why would you select a firm crib mattress over a soft one when it’s so simple?

If you’re really worried, a breathable crib mattress could be the best option for your family.

Finally, the edges and corners of soft mattresses can be molded. This can cause gaps to form between the crib edge and the mattress edge, and newborns may become trapped in these gaps.

Firm Is The Best

Take a look at what some experts say if you need more proof to persuade a spouse, grandparent, or co-parent that a firm bassinet and/or crib mattress is best for your baby:

The National Institute of Child Health and Human Development: “Never place baby to sleep on soft surfaces…. These surfaces can be very dangerous for babies.”

The Center for Disease Control: “Use a firm, flat sleep surface, such as a mattress in a safety-approved crib covered by a fitted sheet.

SafeKids.org (a not-for-profit organization): “A firm mattress covered with a tight-fitting crib sheet is all you need to make your baby sleep like a baby.”

American Academy of Pediatrics“A firm surface is a hard surface; it should not indent when the baby is lying on it.”

American Academy of Pediatrics (again): “The American Academy of Pediatrics recommends a safe sleep environment that can reduce the risk of all sleep-related infant deaths. Recommendations for a safe sleep environment include supine positioning, the use of a firm sleep surface, room-sharing without bed-sharing, and the avoidance of soft bedding and overheating. Additional recommendations for SIDS reduction include the avoidance of exposure to smoke, alcohol, and illicit drugs; breastfeeding; routine immunization; and use of a pacifier.”

Healthy Families BC (a provincial government organization)The mattress should be firm. If it’s worn or has a tear, it’s dangerous. Don’t use it.

Health CanadaCheck that the mattress is firm. Mattresses that are too soft or worn down in any area could create a gap where a baby’s face could become stuck, causing them to suffocate.

The Canadian Pediatric SocietyUse a firm, flat surface for sleep. Waterbeds, air mattresses, pillows, couches/sofas or soft materials are not safe sleep surfaces for babies. Babies can turn onto their side or stomach and bury their face in these soft materials, not getting enough air to breathe.

Dr. Shavon Artis DickersonHead of the Eunice Kennedy Shriver National Institute of Child Health and Human Development’s Safe to Sleep campaign: “…you want to make sure that the baby is on a firm sleep mattress because if the baby rolls over, they could roll over onto a soft mattress where they actually—their face or nose becomes buried in the mattress.”

There isn’t a single professional group working in the field of child health and safety that doesn’t advocate for a firm crib mattress.

The experts have spoken, and they all agree that choosing a firm cot mattress for your infant is a good idea.

How to Tell if a Crib Mattress is Firm Enough

We recommend starting with the FIRMS checklist when searching for a firm crib mattress:

F – Solid and Flat: Look for a firm, flat surface on a crib mattress. On the mattress, there should be no peaks or troughs.

I – Indentation Resistant: When you receive a crib mattress, you should test it for indentation resistance. Simply push the mattress in the centre and all the way around the edges. If your baby’s mattress is firm enough, it will snap back to its original shape rather than adhering to your hand or fingers.

R – Recall List: Double-check that a new crib mattress isn’t on the recall list before allowing your infant to sleep on it. Recalls for infant products may be found here for Americans and here for Canadians. It’s a good idea to double-check both lists just in case.

M – Firm crib mattresses will have strong and sturdy edges and corners that cannot be pulled inwards to create a gap between the crib edge and the mattress. Double-check your crib’s mattress to be sure there aren’t any significant gaps.

S – Soft Isn’t Safe: This is more of a reminder than a checklist. If the crib mattress appears to be comfy to you, it is most likely too soft for your child. Firmer is usually better when it comes to infant mattresses, so don’t be scared to seek for an extremely firm crib mattress.