Is Swaddling Dangerous? The True Relationship Between the Moro Reflex and Swaddles | How to Use Them to Protect Development and Sleep
Is Swaddling Dangerous? The True Relationship Between the Moro Reflex and Swaddles | How to Use Them to Protect Development and Sleep
I hear that swaddling is dangerous, but
the Moro reflex is so strong that my baby won't sleep at all without it...
Are you feeling torn like that between your baby's Moro reflex and
using a swaddle or wrap?
From my perspective as a childcare worker who has observed child development,
and also as a parent myself, I feel that this topic
cannot simply be dismissed by saying
"swaddling is dangerous" or "swaddles are bad for development."
In this note, I have organized as clearly as possible the developmental significance of the Moro reflex,
how to think about using
swaddles and wraps while valuing both "development" and "sleep,"
and guidelines for how long to use them and when to stop.
Are swaddles and wraps bad for development? Purpose and usage are key
I believe that using
swaddles or wraps to dampen the Moro reflex
is not something that is "absolutely forbidden because it is bad for development."
However, it is not a desirable way to use them if parents
are strongly restricting a baby's movement for long periods solely for their own sleep.
The Moro reflex is one of the primitive reflexes that appears
naturally in the process of a baby's brain and nervous system development.
In that sense, if the goal is to "eliminate the reflex itself,"
it becomes difficult to visualize the natural flow of development.
On the other hand, there are cases where the Moro reflex is strong,
causing the baby to wake up with a start every time they fall asleep,
resulting in the baby clearly being sleep-deprived.
In such cases,
using a swaddle to gently restrain the movement of the limbs
can make it harder for sleep to be interrupted,
and can sometimes alleviate the baby's own distress.
The important thing is the focus on
"for whom" and "for what purpose" you are using it.
It is natural for parents to want to make things a little easier for themselves, but
the focus should be on the perspective of
"is the child getting enough sleep?"
and "does the child seem comfortable?"
What is the Moro reflex? Its relationship with baby development
What kind of movement is the Moro reflex?
The Moro reflex is one of the movements called a "primitive reflex"
seen in newborn babies.
When there is a loud noise, or
the moment they are lowered from being held onto a bed,
the baby will typically startle and move their limbs,
spread both arms out as if to say "banzai," and then
bring their arms back in as if hugging something tightly.
This is not something the baby intends to do,
but a reaction that occurs automatically in response to external stimuli.
It is seen from birth,
and it is said that it naturally becomes less noticeable
by around 4 to 6 months of age,
centered around 0 to 4 months of age.
The Moro Reflex as a Baby’s “Startle Alarm”
Think of it as a
“startle alarm” that comes
pre-installed in a baby’s body.
If their posture wobbles or
there is a loud noise,
they react strongly with their whole body
as a sign that “something has happened.”
Even adults, when startled,
might instinctively hunch their shoulders or jump.
The Moro reflex is
easier to imagine if you think of it as a
more primitive, full-body version of that.
Primitive Reflexes and the Image of a “Three-Story Brain”
“Primitive reflexes,” including the Moro reflex, are
movements that are built-in to protect a baby’s life
during the period when they cannot move their bodies at will.
Since it is difficult for them to “think before they move,”
it is easy to understand if you think of it as
the more primitive functions of the brain
automatically flipping the switch.
There is an explanation that compares the brain to a “three-story house.”
The idea is that the first floor is built firmly first,
supporting basic life functions and primitive reflexes,
and then the functions of emotion and thought
are stacked on top of that.
Primitive reflexes can also be thought of as playing the role of
gathering information through the body, such as “if I move this way, I feel this way,”
during this foundational period.
The way they jerk their limbs in the Moro reflex is also
not just a “mysterious movement,” but
can be understood as part of a process of feeling body position and balance,
and practicing protective reactions when they feel unsteady.
When Does It Appear and When Does It Disappear?
An important point about primitive reflexes is
not just that they “appear,” but
that they “disappear when the time comes.”
The Moro reflex is seen in most babies from birth,
is most noticeable around 2 to 3 months,
and is said to gradually subside
by about 4 to 6 months.
This is because, although primitive reactions initially support body movement,
the ability to control movements on their own
gradually develops.
Therefore, the natural subsiding of primitive reflexes is seen
as a sign that they are climbing the ladder of development
one step at a time.
“Reflexes are neither ‘good to have’ nor ‘bad to suppress’”
What is important here is
not to simply think, “Since the Moro reflex is a good thing,
it is better to have it happen a lot.”
While the presence of the Moro reflex itself is normal,
it can sometimes cause the baby to wake up with a start many times during sleep,
leading to extremely fragmented sleep for the baby.
From a developmental perspective, what is important is balancing the need not to treat the reflex itself as an enemy with the need to adjust the environment when life becomes difficult.
That is why I believe it is realistic to respect the flow of development, including the Moro reflex, while finding a good middle ground by using techniques like how you hold and lay the baby down, and using swaddles when necessary.
Swaddles and wraps are “tools to help with sleep”
Using a swaddle to turn down the “volume” of the Moro reflex
Swaddles and wraps are cloths or specialized bedding designed to wrap a baby’s arms and upper body with just the right amount of firmness.
By wrapping them securely, you can suppress the large movements of the limbs caused by the Moro reflex and reduce the intensity of the startle response.
Think of it like “turning down the volume of a surprise alarm.”
The alarm still goes off, but the idea is to make it a little quieter so that it isn't so loud that it makes them jump awake every time.
Even if the Moro reflex doesn't disappear completely, reducing the movement can make it easier for the baby to drift back to sleep.
As a result, sleep is less likely to be fragmented, and you can expect an increase in the time they can “sleep a little longer at once.”
Sleep is “charging time” for development
When talking about swaddles, along with the concern that “isn't it bad for development to suppress the Moro reflex?”, there are also voices saying, “but I'm also worried that they won't sleep at all.”
What is important here is the perspective that sleep itself is also a very important time for development.
During sleep, the baby's body undergoes processes that support development, such as the secretion of growth hormones, the organization of stimuli and experiences received during the day, and the regulation of the immune and autonomic nervous systems.
In other words, sleep is not just a time for resting; it can be called “charging time” and “maintenance time” for the development of the brain and body.
If a baby wakes up too many times due to the Moro reflex and remains in a state of constant sleep deprivation and exhaustion, there is a concern that this “charging time” cannot be properly secured.
In that sense, it is not the correct answer to leave the reflex completely untouched; it is important to look at both the role of the reflex and the importance of sleep to find the right balance.
A swaddle is not a “cheat code,” but a minor environmental adjustment
Reading this far, it might sound like “then is it better to use a swaddle as much as possible?”, but of course that is not the case.
What is important is the “core principle” when using a swaddle.
It is natural for parents to want a little relief,
or to feel that holding or breastfeeding in the middle of the night is difficult.
However, if you let that feeling alone lead you to
“wrap them as tightly as possible and use it for as long as possible,”
you may lose sight of
the perspective of your baby's development and safety.
Swaddling is not a shortcut for parents to take it easy,
but rather, it becomes easier to understand its purpose
when you think of it as one form of environmental adjustment
to alleviate your baby's sleep deprivation or discomfort.
When you feel that “parenting is tough,”
if you start from the perspective that
your baby might be struggling to sleep just as much,
it becomes easier to balance how you use it.
How to Use Swaddles Without Making It a “Constant or Vague” Habit | When to Stop? How Do You Wean Them Off?
Let Them Move Their Limbs Freely While Awake
Swaddling is not meant to stop all of a baby's movements,
but is fundamentally used as “support to make it easier to fall asleep when they want to sleep.”
If you keep them wrapped all day long, even while they are awake,
there is a concern that the experience of moving their limbs freely
and the experience of confirming their body position on their own
will decrease.
Primitive reflexes, including the Moro reflex,
are considered part of a process where,
while moving their bodies significantly,
they feel gravity and balance,
and send information like “this is what it feels like when I move this way” to the brain.
Therefore, if you fix them tightly even when they are awake,
you may be reducing the time they have to practice
connecting their body and brain.
A Guideline for Stopping Is Around 3 to 4 Months or Signs of Rolling Over
To reduce anxiety about relying too much on swaddling,
it helps to roughly decide on a “time to stop.”
As a guideline,
once they reach around 3 to 4 months of age,
it is reassuring to start thinking, “It’s almost time to graduate,”
and move toward stopping completely
once signs of rolling over appear.
There are individual differences in when babies roll over,
and some early babies may show signs even sooner,
so it is important to look closely at “current movements”
rather than just “age in months.”
Before stopping completely,
you can also try a transition period, such as
“trying to leave one arm out”
or “trying not to wrap them for part of their nap.”
The important thing is
not to pressure yourself by thinking,
“I have to stop it completely starting today.”
It is enough to gradually increase the time they are not wrapped
while observing your baby's condition.
“Eliminating the Moro Reflex” Does Not Need to Be the Goal
The Moro reflex is something that naturally appears
while a baby's brain and body are developing.
The fact that it occurs is not a bad thing;
it will gradually weaken when the time is right,
and will pass the baton to other movements and reactions.
The purpose of using a swaddle is
not to eliminate the reflex itself, but
to make the state of
“wanting to sleep but being unable to”
or “seeming distressed from waking up repeatedly”
caused by the reflex, a little easier to manage.
In fact, if they are
able to fall back asleep even after moving with a startle,
you do not necessarily need to suppress it with a swaddle.
Conversely, if they wake up crying every time they startle
and are clearly suffering from ongoing sleep deprivation,
relying on a swaddle for a short period
can sometimes make life easier for both parent and child.
For those who feel that “swaddling is dangerous”
Reasons why people feel “swaddling is dangerous”
Over the past few years, on social media and elsewhere,
I have seen an increase in strong language such as
“swaddling is dangerous” or “it is bad for development.”
Seeing that,
I think many people are feeling anxious, thinking,
“I’ve already used it” or “I’m continuing to use it because it’s convenient, but is it okay?”
On the other hand,
because “they sleep so well anyway”
or “they won’t sleep at all without it,”
the benefits are often emphasized,
and with little information on “how long” or “how to stop,”
it is sometimes used aimlessly.
Perhaps both extreme anxiety and information that prioritizes only convenience
are increasing the confusion.
What is important is to look at this child right now
Rather than deciding on the Moro reflex and swaddling based on
“I must do it” or “I must never do it,”
this is a topic I want you to think about by looking at the baby in front of you.
If they startle a little,
but can fall back asleep immediately,
and are moving and playing in a good mood during the day,
a swaddle may not necessarily be needed.
On the contrary,
if the Moro reflex is strong and they wake up crying every time they sleep,
they are clearly sleep-deprived from waking up over and over again,
and the adult accompanying them is also quite cornered,
then for a short period while sleeping,
borrowing the power of a swaddle
is a perfectly realistic choice.
Not “I’ve already done it,” but “what to do from now on”
What I want to convey is that
the Moro reflex is a sign of development that appears naturally
while a baby’s brain and body are growing,
and that a swaddle is one of the environmental adjustments
that can be used skillfully to make the situation of
“wanting to sleep but being unable to” due to that reflex a little easier.
Instead of using it aimlessly for a long time,
by using it “only when sleeping”
and “while being conscious of when to stop,”
it becomes easier to balance development and sleep.
And above all,
rather than thinking “it’s no good because I’ve already done it,”
I think you can feel a little more at ease
if you have the perspective that
you can just adjust how you use it little by little from now on,
now that you know the information.
Conclusion: My story of re-engaging with swaddles
Finally, I will write a little about myself as well.
At first,
thinking “I just need them to sleep somehow,”
there was a period when I used swaddles almost reflexively.
My own desire to get some sleep came first, and
I honestly feel that I didn't think much about
the meaning of the Moro reflex or
its importance to the baby.
After that,
I learned that the Moro reflex is part of the flow of brain and physical development,
and once I began to see its aspect as a "sign of development,"
I changed how I use swaddles a little.
Now, I think of swaddles not as
"something to eliminate the reflex,"
but as "a tool to help out a little
when they want to sleep but can't."
Instead of leaving it on all the time,
I use it only when it's time to sleep,
while also being mindful of when to stop using it.
I believe that level of distance
is just right for me.
If you are currently
"wondering if it's okay to use"
or "wondering if I should stop,"
I would be happy if this text serves as even a little bit of food for thought.
Neither the Moro reflex nor swaddles
are a matter of which is right or wrong,
but rather a theme for finding
the perfect balance for the baby and family right in front of you.