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In the early days at home with a newborn, most people prefer to swaddle their babies for naps or overnight sleep sessions, as it's one of the only ways many babies will get comfortable enough to fall asleep—and stay asleep—aside from contact snoozing in the arms of a parent or caregiver (which, don't get me wrong, is nice, but just isn't sustainable).
Swaddling your baby will get you through the first few months, until they're ready to level up their skills—and level up their parents' anxiety—by learning how to roll over.
Swaddling your baby will get you through the first few months, until they're ready to level up their skills—and level up their parents' anxiety—by learning how to roll over.
It's an amazing and also terrifying time.
As you watch your children grow, you quickly realize that no matter how nervous you may be, you have to let them do just that: grow (while you watch them on a monitor to make sure they're doing okay while they do their thing).
But once your little infants are getting ready to reach that rolling milestone, then what?
No more swaddles, for one. Flat sheets and loose blankets aren't recommended until children are at least 12 months old, due to the risk of suffocation, strangulation, and sudden infant death syndrome.
Some people prefer to wait even longer, until their little ones are closer to 18 months old, to introduce blankets, just for their own peace of mind.
Wherever you fall on this spectrum, once your babies get rolling, you'll need to get rolling on your plans for the next sleep stage.
What is a sleep sack?
Cue wearable blankets, also known as sleep sacks. Think of them as something similar to a sleeveless, slightly oversized but lightweight sleeping bag that can be zipped shut.
Sleep sacks help your baby regulate their temperature and sleep safely because they do not restrict the arms. Because they are pouch-like, they give your baby the freedom to move as needed, which promotes healthy hip development, and allow them to sleep comfortably. On the flip side, they are restrictive enough (in a good way) that your little one won't be able to maneuver and execute an escape over the side of their crib.
When it's time to start using sleep sacks, some parents opt for wearable swaddles to help ease the transition from the full swaddle they've known to the new sleep sack they will come to know and love (more on this below).
If you act really excited about sleep sacks, your twins will be really excited to get to wear them; at least, that's what we found with our babies. We just built up the idea of wearing them as being a really cool thing, and our twins jumped right on board with us.
They would just snuggle into their sleep sacks when it was time to get ready for bed and grin from ear-to-ear while we zipped them shut. Getting lowered into their crib and reaching for their sleep sack became a cue that it was time for bed, and they associated that with getting ready to fall asleep.
When do you start using a sleep sack?
According to the American Academy of Pediatrics, it's time to say, "See ya," to the swaddle once your babies start showing signs they're learning how to roll over. This can be anywhere from two to four months of age, depending on each individual baby.
You can go cold-turkey from the swaddle once they start showing these signs, or if they're getting close to that milestone, you can prepare them for the transition over a short period by leaving one or both arms out of a wearable swaddle at naptime or bedtime.
For that transition time, we really liked the SwaddleMe blanket wrap by Ingenuity. These adjustable, Velcro-winged swaddles are rated for babies who are three to six months old (14 to 18 pounds and up to 30 inches long) and help mimic a womb-like feeling for your babies. This helps prevent the startle reflex (AKA the Moro reflex) and keeps your infants calm and comforted, so they stay asleep longer.
With these wraps, you can tuck both arms in, and then progress to just one arm in while the other one is out, eventually moving to having both arms out while they wear the swaddle. Once they're used to that configuration, (usually after a few sleep sessions with each stage), graduating to sleep sacks should be pretty easy (it was for us with this method!).
SwaddleMe by Ingenuity Swaddling Blanket
These are swaddling blankets by Ingenuity. They have an adjustable Velcro closure for easy sizing that grows right alongside your babies until they start rolling.
You may notice one or both of your twins wake up more often once they're out of their swaddle and into their sleep sack. This is probably thanks, in part, to their startle reflex, which can cause them to wake up at the drop of a hat from a variety of stimuli.
It may take your twins some time to get used to their new sleeping arrangements, and depending on how old they are when you do the switch from swaddle to sleep sacks, you might consider using this as an opportunity to start sleep training your twins.
We did sleep training right after we switched them over to sleep sacks. We got them used to the wearable blankets during their naps for a few days and then added them into the overnight routine when we officially started sleep training. You can read all about how to successfully sleep train your twins, here.
When do you stop using a sleep sack?
How do you know when your all-of-a-sudden-toddlers are done with sleep sacks?
It's usually right around the time they grow out of the biggest size, which is, coincidentally, also right around the same time they start to figure out how to work the zippers on the blankets themselves.
When you reach this point, of course, will depend on your child's height and weight, so this may be a different point for each individual kid.
You'll know just by looking at your toddlers if it's time to graduate to the next sleep set-up with just blankets because they'll either be Houdini-ing their way out of their blanket mere moments after you zip them up, or you'll clearly be able to see that things are getting snug and they're running out of room at the bottom of the sack.
What are the different styles?
For the early stage, when you prepare your twins for the transition from the swaddle to a sleep sack, the adjustable swaddle wrap, where you can tuck both arms, one, or none into the blanket, is very useful.
Once your babies are ready to start rolling, you'll be ready for the other style, which is the sleeveless sack that ensures both arms are free to help prevent the risk of strangulation and suffocation.
As Halo dutifully reminds parents and caregivers, to follow safe sleep practices and help prevent the risk of SIDS, laying your baby on their back is best.
Once your babies have the core strength to roll themselves from their back onto their tummies, it is typically fine to let them sleep on their stomachs, but this is always something you can run past your pediatrician if you have any hesitations.
Halo sleep sacks are soft and cute, and they do a good job. They have a little fabric pocket to tuck over the zipper pull, so that inquisitive minds can't chomp down on the teeth of the zipper with the teeth that are erupting through their sensitive, little gums.
HALO Sleep Sack with a TOG Value of 0.5
This is Halo's 0.5 TOG sleep sack. The wearable blanket is cotton and has a zipper that opens from the bottom for easier diaper changes.
While Halo's zipper guard protects tiny teeth, other options account for a toddler's curiosity as they grow. The Baby Beekeeper Infant Wearable Blanket by Burt's Bees incorporates an interior zipper guard and zipper pull cover that helps prevent your toddler from pulling at or trying to chew the zipper when they get bored.
It may not be immediately obvious how important this is, but I certainly noticed and was impressed by this feature because I know someone whose baby got their front tooth stuck right through the middle hole on the pull tab of a different brand of sleep sack. The zipper guard that is included on the Burt's Bees sleep sacks prevent this from happening.
You'll also want to think about how the sleep sack will grow with your baby...
You'll also want to think about how the sleep sack will grow with your baby because they come in different sizes rated for different weight and length specifications. Be sure to check these figures when deciding on which ones to go with, to make sure they're within the right range for your little ones.
The Baby Beekeeper Infant Wearable Blanket by Burt's Bees is a great choice as your babies grow into toddlers. This sack is rated for 12-18 months (22 to 28 pounds; our twins are still wearing them at 24 months' old because they're still under the maximum weight threshold.
Burt's Bees Baby Beekeeper Infant Wearable Blanket
This is the Burt's Bees Baby Beekeeper Infant Wearable Blanket. The interior zipper guard and zipper pull cover help prevent your baby from pulling at or trying to chew the zipper when they get bored.
Nested Bean Zen weighted sleep sacks are engineered with adjustable snap closures at the shoulder, meaning the sleep sack will grow with your baby, which is a plus. Because of this design, our twins were able to use these sleep sacks until we introduced blankets for bedtime, when they were 18 months old.
Another option to weigh when it comes to which style to go with is whether or not you choose a lightly weighted sleep sack or not. Nested Bean Zen sleep sacks have a small weight on the chest of the sleep sack, which mimics the sensation and comfort of a parent's hand gently resting on their chest. It helps prevent their startle (Moro) reflex from waking them up throughout the night.
One more consideration to mull over when choosing a sleep sack is the type of closures it has because you want to make sure that overnight diaper changes go off without a hitch.
...you want to make sure that overnight diaper changes go off without a hitch.
Some sleep sacks feature snap closures, while others have a zipper. Similar to fighting with pajamas in the newborn days, I suggest going with a version that has zippers and not snaps. My reasoning for this is outlined in this article, here.
The Nested Bean sacks have a two-way zipper closure, which makes for easier, quieter changes overnight that are less likely to wake your sleeping babies.
Nested Bean Zen Weighted Sleep Sack
This is the Nested Bean Zen weighted sleep sack. It's designed to help prevent wake-ups during sleep regressions and help your baby learn to self-soothe.
Take temperature into account
Until your baby is closer to nine months old (or even up to 12 months old), they cannot fully adapt and regulate their body temperature to external conditions. Babies are totally reliant on their parents and caregivers to monitor and adjust their environment as needed to ensure they are comfortable.
You don't want your little ones to be too cold and you also don't want them overheating. The ideal temperature for your babies' nursery is between 68 and 72 degrees Fahrenheit (20 to 22 degrees Celsius). Some baby monitors will provide a real-time temperature on their feed, so you can see at a glance if anything needs to be adjusted.
Babies are totally reliant on their parents and caregivers to monitor and adjust their environment as needed to ensure they are comfortable.
When it's time for your twins to lay down for a nap or their overnight slumber, it's also important to remember that their fingers and toes aren't good indicators of their actual warmth level. If you're concerned, feel their core, torso, or neck in order to get a proper indication of how warm or cool they are.
Alternatively, you can take their temperature using a thermometer to get an accurate reading; oftentimes, a baby may feel warmer or cooler than they actually are, and the thermometer can put those worries to rest—so that you can also rest.
Talk about togs
Beyond the temperature in your babies' bedroom, another factor that contributes to how comfortable your twins are is how warm their sleep sacks are. Sleep sacks have different thermal overall grade (TOG) values, so you'll want to pay attention to these numbers when you purchase sleep sacks. TOGs are units of measurement that indicate the level of insulation and warmth of sleepwear and bedding.
The TOG value you'll want will vary throughout the year, depending on factors like the season and its accompanying climate, where you live and how hot or cold it gets in that specific locale, and what your baby will be wearing to sleep underneath their sleep sack.
Finding the right TOG value for the different seasons will help your babies be comfortable, so they can get a more restful sleep, which will help you get a more restful sleep.
Wearable blankets can range from a TOG of 0.5 to 4.5. In general, a TOG value of 2.5 will work in most scenarios year-round for temperatures ranging from 61 to 68 degrees Fahrenheit (16 to 20 degrees Celsius). When temperatures spike to, say, 69 to 74 degrees Fahrenheit (21 to 23 degrees Celsius) in the summertime, a TOG of 1.0 is ideal. If it gets even hotter (75 to 81 degrees Fahrenheit; 24 to 27 degrees Celsius), you may want a sleep sack with a TOG that is lower than 1.0.
Finding the right TOG value for the different seasons will help your babies be comfortable, so they can get a more restful sleep, which will help you get a more restful sleep.
What should a baby wear under a sleep sack?
What your children are wearing during the day may not necessarily be what they should be wearing when they lay down for a nap or bedtime. If they're wearing jeans for the day, you may not want them in denim for their nap on a hot, summer day.
This concept comes back to factors like the current season, the weather of that particular day, and the bedroom's internal temperature.
Depending on how warm your babies' room is and the TOG value of their sleep sacks, what your child wears underneath their wearable blanket can vary...
Depending on how warm your babies' room is and the TOG value of their sleep sacks, what your child wears underneath their wearable blanket can vary from just a diaper on a hot, sunny day, to a t-shirt and shorts, a long-sleeved top and pants, or a cotton or fleece sleeper. These are things you need to monitor and decide when laying your kids down to make sure they don't overheat or get too cold while they're resting.
When it's hotter outside, you would, in theory, use a lower-value TOG sack, and it would, therefore, be more likely that your child would be wearing fewer layers underneath the sack. Higher-rated TOG values would be used for colder seasons, which could mean your baby might have more, or warmer, layers underneath.
What material is best for a sleep sack?
It depends on what you're looking for. You probably want something that is soft and breathable. Hypoallergenic fabrics, like cotton and muslin, encourage air flow and help with temperature regulation by preventing overheating, while bamboo viscose fabrics can absorb and evaporate sweat more quickly than cotton, so could be the better choice for someone who runs a little warmer when they sleep.
Wool, fleece, and microfleece fabrics have lower breathability, which could potentially lead to overheating, so if you opt for a sleep sack in these fabrics for comfort on colder days, you'll want to be sure to monitor things closely, since your kids can't just kick their sleep sack off if they get too warm while they're sleeping.
How many sleep sacks do I need for my twins?
We cover this, among other things, in our article about what you actually need two of if you're expecting twins, but we'll say it again here: It's nice to have three sleep sacks per baby, at least until they're about a year old—one that's in the laundry, one that's clean and currently being used, and one for just in case of an accident after you've just grabbed the back-up.
Consider having different TOG values available in your arsenal based on your twins' ages / weights and what season they're expected to reach those marks. And be sure they are rated for the correct size and height of your children (read: the suggested age range on a particular sleep sack is a guideline; go by what it lists for height and weight specs, not age, as every baby is different and reaches those stats at slightly different times).
Embrace the next sleep stage
When your twins reach one of their first big milestones and are learning how to roll, it's time to ditch the swaddles and upgrade your little ones to their very own sleep sacks.
There are different factors to consider when choosing which wearable blankets are the right fit for your ever-growing babies, but with the right balance, timing, and approach, sleep sacks can save the day—and night—in your household.
And before you can say, "Peekaboo," your newborns will be sleeping just like a baby in a few short winks.
What sleep sacks did you use with your twins? Why were they your favorite? What did you consider before choosing which ones to go with? Let us know in the Comments section below.
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