Woolino 4 Season Baby Sleep Bag Review: A Sleep Sack that Grows with Infants through the Age of 2

Clothing & Accessories

Woolino 4 Season Baby Sleep Bag Review: A Sleep Sack that Grows with Infants through the Age of 2

Woolino 4 Season Baby Sleep Bag Review: A Sleep Sack that Grows with Infants through the Age of 2

We all know that babies, and the million+1 products they need, can really add up and make the whole first few months – even before baby arrives – seem overwhelming and daunting. But that’s why I love the Woolino 4 Season Baby Sleep Bag! Designed to fit babies from 2 months – 2 years, this sleep sack is made out of merino wool and will help keep your baby at the perfect temperature all year round.

Keep reading to find out more…

For Babies Ages 2 Months to 2 Years


Woolino’s award winning 4 Season Merino Wool Baby Sleep Bag will keep your baby at a perfect temperature all year round. Designed to fit babies 2 months to 2 years, your baby will never be too hot or too cold while sleeping again!

100% natural and fully machine-washable, Woolino’s Sleep Bag truly is an excellent value since it comes in one universal size that fits babies from for a full 2 years – as opposed to most baby products and clothing that they only get a couple months use out of. Plus, as mentioned, thanks to Merino’s unique ability to regulate body temperature, it keeps your baby warm when it's cold and cool when it's hot.

Available in a multitude of prints that include Earth, Lilac, Gray Stars, Navy Blue, Violet, Rose, Panda, Whales and Boats, Woolino’s Ultimate 4 Season Baby Sleep Bags are not only great for every season, but every style too!

Plus, Woolino’s Sleep Bags feature double shoulder snaps and a two-way side zipper so you can either choose to only open up the bottom or open it up completely flat for easy dressing without waking your baby! It also has zipper-pull guards to protect baby's skin and to prevent them from chewing on the zipper pull. Furthermore, a closable seat-belt opening allows for easy transfer between stroller, car seat and crib, so you can keep your baby’s sleep routine intact while on the go.

Woolino’s Ultimate 4 Season Baby Sleep Bags are also #1 rated and #1 selling in both the US and Canada, and Winner of Mom's Choice Award, Creative Child's 2012 Top Choice of the Year Award and Green Scene Mom Award 2016.


The story of Woolino begins with a new mom, a sleep-averse baby and all those same feelings felt by parents the world over…

When the founder, Mimi, had her first child, she spent hours online researching the best sleepwear for him. Her requirements were twofold: it had to keep him comfortable and it had to keep him safe.

Like most new mothers, she wanted to do everything she could to minimize the risk of Sudden Infant Death Syndrome (SIDS). She was looking for something that would address both the key risk factors: suffocation due to loose blankets being pulled over the face, and overheating.

Like many problems, she found her answer in an old-world solution - the baby sleeping bag. A sleep bag would act as a wearable blanket, which couldn’t be pulled up or kicked off during the night.

But having found the solution, she found that the ones available didn’t address her other concern: comfort. Those sleep sacks made of synthetic material could cause overheating (a contributing factor to SIDS), and those made of cotton were not warm enough to be used during the winter months.

It wasn’t much later (midway through a night feed, in fact) that the ideal material came to mind. Being an outdoor person, she knew from personal experience of the unique and amazing qualities of merino wool. She realized that merino wool would be the ideal fabric for baby blankets. It was super soft, regulated body temperature, and was easy to clean. And so, she set about looking for a merino wool baby sleep sack.

There was nothing.

Thankfully, as an architect and urban planner, Mimi was used to creating solutions where there previously were none, and so, with sleep still in her eyes, she set about designing a merino wool baby sleep bag. Mimi became a mom and a mompreneur, all within a couple months.

Many night feeds and several prototypes later, Woolino’s sleep bag was born; the first merino wool sleep bag available in the US. Demand was immediate, and word quickly spread online about this new baby sleeping solution. Within a few months of launch, it became a bestseller and the number one rated baby sleep bag on Amazon – a position it has held ever since.


Merino wool truly is the perfect material for babies – for both their safety and sleep quality. In fact, medical studies have shown that babies sleeping in merino settle more quickly, cry less, sleep longer, feed better and gain weight faster.

So what makes Merino Wool so great?

Reassuringly Safe and Healthy:

Regulates body temperature: Babies don’t have the ability to regulate their own body temperature that adults have, so it’s important to make sure they’re not too cold or overheating, especially during the night time.

Merino wool creates a micro-climate around your baby, which maintains a consistent temperature for them. It has the ability to absorb water away from your baby’s skin and release it into the atmosphere during the summer. In winter, it will trap and circulate warm air, keeping your baby warm.

A more comfortable temperature allows for a deeper and more restful sleep for your baby, so that that energy can be diverted to growth and development.

Reduces the risk of overheating: Overheating has been named as one of the key risk factors of Sudden Infant Death Syndrome (SIDS). So, the fact that merino wool has unmatched body temperature regulation properties does not only mean better and healthier sleep for your baby, but it also means a safer sleep all round.

Healthy sleep for healthy growth: Medical studies have found that babies that slept with merino wool had lower rates of activity and a deeper, more restful sleep. They settled more quickly, cried less, slept longer and gained weight faster.

At the Cambridge Maternity Hospital, Scott and Richards investigated the effects of Merino on premature and low birth-weight babies and found that they gained an extra 10g a day compared to babies that weren’t sleeping on Merino.

Hypoallergenic: Babies with sensitive skin or conditions, such as eczema, love merino wool – it’s hypoallergenic, so won’t irritate their skin. Not only is it incredibly soft and breathable but, because it is composed of the same protein that makes up the outer protective layer of our skin, it works in total harmony with our skin’s own protection mechanisms. It also inhibits bacteria, so it minimizes other allergenic problems.

Soft and Comfortable:

Merino will not itch or irritate delicate baby skin. In fact, it’s one of the softest materials around. The wool fiber produced by merino sheep is significantly finer than other types of wool, so it feels luxuriously soft and gentle against a baby’s skin.

Retains Warmth Even When Wet: Unlike any other fiber, merino wool will keep baby warm, without feeling damp or clammy, even when it’s wet. It absorbs moisture both between the fibers and inside of them, so it feels dry. In fact, it can absorb a massive 35% of its weight in water and still keep its warming properties!

Lightweight: Compared to traditional wool, Merino is extremely fine and lightweight – you get all the warmth with none of the bulk of traditional wool.

Exceptionally Breathable: No other fabric “breathes” like Merino wool. The fact that merino wool can absorb an amazing 35% of its weight in water, without feeling damp, and quickly release it into the atmosphere makes it the most breathable fabric around. This means your baby will stay dry and comfortable whatever the environment.

Completely Natural:

Merino wool offers the perfect solution for families concerned about their environmental impact because it is 100% natural and renewable fiber.

100% Natural: Merino wool is grown year-round by Australia's 70 million Merino sheep, consuming a simple blend of water, air, sunshine and grass.

Biodegradable: Because Merino wool is made out of keratin, much like human hair, it is completely biodegradable. When it is eventually disposed of, it will breakdown, decomposing to release vital nutrients back into the soil, acting like a fertilizer.

Renewable: Every year Merino sheep produce a new fleece, making Merino wool a completely renewable fiber source.

Naturally durable: Merino is so durable because each fiber is made up of elastic elements, which are able to bounce back when released from pressure. In fact, merino wool fibers can be bent 20,000 times without breaking!

Easy Care:

Machine Washable: Merino wool’s antibacterial and odor resistant properties mean that it does NOT need to be washed as often as other fabrics. And when it is your turn to wash it (accidents do happen), it can be done in a standard machine and tumble dried on a no-heat setting – there’s none of the hand washing fuss traditionally associated with wool products. [See care instructions.]

Naturally antibacterial and odor resistant: Merino uses mother nature’s washing machine, and is naturally antibacterial, anti-fungal and anti-static. It disinfects itself in fresh air and is naturally resistant to odors.

Naturally stain resistant: Merino fiber has a protective layer that prevents stains from being absorbed. It’s static-resistant nature also means it picks up less dust from the air.

Merino wool vs. traditional wool:

Many people think of wool as an itchy material, unwelcome against the skin. Merino wool is an entirely different fabric, thanks to those superfine fibers that merino sheep produce. It’s smooth, silky-soft, and comfortable even against the most sensitive skin.

Merino wool vs. synthetics:

Synthetic fibers such as polar fleece, polypropylene & polyester are made from petroleum. They cannot breathe, quickly feel clammy and build up stink, and can cause overheating. Synthetics are highly flammable, so in order to comply with US fire safety regulations required in babywear, they need to be treated with chemical fire retardants.


$99.99 + FREE Shipping*, FREE Returns & NO Sales Tax outside Ohio


Woolino Ultimate 4 Season Baby Sleep Bags can be purchased directly through their Online Store, or at select retailers nationwide.


Coming up on Baby #3, I know, first-hand, what it’s like to have a lot of baby products. And the worst part, many of them were barely even used because babies grow so quickly! Hopefully with multiple kids the stuff will at least get a little more use than it would otherwise…

But that’s why I have come to love Woolino’s Ultimate 4 Season Baby Sleep Bags so much – because it “grows” with your baby! With universal sizing, meaning that it will fit a baby from 2 months to 2 years, not only will you stop having to buy larger sizes [from a price standpoint], the consistency in sleepwear will allow your baby to always associate the comfort of their sleep sack with a good night’s rest. Something we could all use more of!

Plus, you don’t have to worry about the changing weather either – another constant issue us parents seem to have when buying clothes for our babies. Now, instead of buying a different sleep sack for different seasons, you just need one Woolino Sleep Bag for your baby to keep them comfy year-round!

Now, I will admit that I haven’t personally been able to test this out on one of my own children – because my daughter is well on her way to 3-years and my baby isn’t due until September – but this is definitely one of the products I am most excited to try once he gets here! Plus, reading all the reviews – and knowing that this is the #1 rated sleep sack both here and in Canada – assures me that this product has to be great! Just feeling the softness of the material and knowing all the benefits of merino wool + the features of the product itself, how could you go wrong?!

Do you have a baby of your own, or are you looking for a useful gift for a friend’s, then you should definitely check out Woolino’s Ultimate 4 Season Baby Sleep Bags. Because it’s those small steps that make healthy living a lifestyle – so why not take one today?!

For more information about Woolino, please visit their website and check them out on Facebook, Instagram, Pinterest and Twitter.

And don’t forget to CONTACT Healthy Fit Fab Moms today to learn how we can help you and your family live a healthy, fit, and fabulous life! Please LIKE us on Facebook and FOLLOW us on Instagram, Pinterest and Twitter to stay connected as well!



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