Why a Waterproof Crib Mattress Is a Must

June 27, 2024

When it comes to all the baby gear out there, there are certainly items you can do without. But a waterproof crib mattress sure isn't one of them! 

Considering that newborns sleep up to 16 hours a day, their crib mattress is arguably one of the most important baby items you'll invest in – so you'll want to get it right. At Lullaby Earth, we believe in safer, healthier, cleaner sleep, which is why we say a waterproof crib mattress is a must. 

Why? Because babies are m-e-s-s-y. Let’s break it down.

The Problem With Non-Waterproof Crib Mattresses

Aside from restful sleep and blissful daydreams, there’s a lot that can happen on your baby’s crib mattress. You know, like accidents, spills and diaper blowouts – all of that not-so-dreamy baby stuff. And if your crib mattress isn’t waterproof, there’s a chance that all of those accidents could – and probably would – seep into the layers of your baby’s mattress. Yucky. 

Then comes the issue of cleaning the soiled crib mattress. Introducing water into the core of a NOT waterproof crib mattress could lead to mold, mildew and other bacteria growth inside your baby’s crib mattress. Aka, your baby could be breathing in all that yuckiness for those 16 hours a day that they’re on their crib mattress (plus any leftover mess, because you’ll never know whether you got it all cleaned up or not…).


With this knowledge, we'd say it's pretty easy to see why all of our crib mattresses at Lullaby Earth are waterproof or come with waterproof covers!

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Health Risks of Mold and Mildew 

Mold and mildew aren’t just gross – they can cause very real health effects. If your child is exposed to mold and mildew, it can irritate their: 

  • Eyes
  • Ears
  • Nose
  • Throat
  • Lungs

And, for littles who are more sensitive to mold, exposure can cause severe allergic reactions that range from skin rashes to shortness of breath to asthma attacks. 

Why Vinyl/PVC Is Not the Answer

You can’t avoid all of the mold and mildew out there in the world or even in your home, but you can certainly avoid it inside Baby's safe space by waterproofing their crib mattress. But if you’re really trying to make their sleep space safer and healthier, you have to be careful about the type of waterproofing materials you choose!

Is vinyl safe? Polyvinyl chloride (most commonly referred to as vinyl or PVC) is a type of plastic that can be found in toys, plates, changing pads, teethers and – you guessed it – crib mattress waterproofing. If vinyl/PVC is used to make so much baby stuff, it can’t be bad for them, right? Unfortunately, this isn’t the case. 

Health Effects of Vinyl/PVC

baby rubbing facebaby rubbing face

Vinyl/PVC has been named “the most toxic plastic” by organizations like MADE SAFE®. Chemicals like vinyl/PVC have some serious endocrine disruptors in them, which can affect your little one’s hormones that contribute to: 

  • Growth
  • Metabolism
  • Stress responses
  • Reproductive health
  • And more! 

Even worse, materials like vinyl are known to off-gas over time. This means that your little one can be exposed to phthalates and other toxic chemicals if vinyl/PVC if it is used in their crib mattress.

Ecological Effects of Vinyl/PVC

Vinyl/PVC is harmful to Mother Nature, too. When toys and other items made with this material end up in landfills, they release dioxins into the air, soil and water. These dioxins can then build up in the food chain (i.e. meat, fish and dairy products that we eat), which is actually where 90% of our exposure to dioxins comes from. 

Dioxins aren’t just damaging to the planet – they can also cause a variety of health issues for our little ones and for wildlife, including:

  • Reproductive issues
  • Developmental problems
  • Hormone disruption (AKA the endocrine disruptors from earlier!)
  • Cancer
  • Accumulation in the fatty tissues of animals 

Knowing how bad these chemicals are for your little ones and the environment, we should avoid toxins in our nurseries (and our homes!) as much as possible.

Safer Waterproofing Materials

Luckily, finding safer and healthier waterproofing materials isn’t as difficult as it sounds. At Lullaby Earth, we only use materials that meet the FDA’s food contact standards to make our crib mattresses waterproof. This means they’re easier to clean, safer for your littles AND better for our environment – talk about a “win” for everyone! Let’s take a closer look. 

waterproof crib mattress in cribwaterproof crib mattress in crib


Polyurethane waterproofing – not to be confused with polyurethane foam – can be a safer material to use for waterproofing because it avoids the use of harmful additives like heavy metals, formaldehyde and phthalates, which are commonly found in some traditional waterproofing products.


Similar to polyurethane, polyethylene is also a safer, healthier material for waterproofing when it isn’t combined with additives. At Lullaby Earth, we only use plant-based polyethylene for the waterproofing of our crib mattresses. 

Are Breathable Crib Mattresses Waterproof?

Breathable crib mattresses are great for airflow, but if they're not waterproof, they can trap all kinds of yucky stuff from those little accidents we were discussing before. You don't want your baby breathing that in! A crib mattress that is breathable but not waterproof begs the question, “What's my baby really breathing in?” Making sure it's both breathable and waterproof keeps things safer and cleaner.


A waterproof layer at the surface of the crib mattress is the best way to ensure your baby isn’t breathing any mold, mildew or other allergens and contaminants into their tiny lungs. 

More Crib Mattress Safety Tips

toddler standing in crib on waterproof crib mattresstoddler standing in crib on waterproof crib mattress

Aside from having a waterproof crib mattress, there are a lot of other safety tips you can learn to ensure your little one will be safer and healthier as they rest. And, as parents ourselves, we know this can be overwhelming at times! Luckily, Lullaby Earth has all the tips. You can learn more about crib mattress:

 And more in our blog, The Ultimate Baby Sleep Safety Guide.

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