Understanding Newborn Shivering: What's Normal And What's Not

Newborns don't shiver when they're cold, but they may still exhibit shivering-like movements. These are usually harmless and caused by slowly developing muscle control, excitement, or a reaction to something. However, in some cases, it could be a sign of something more serious, such as a seizure or low blood sugar. It's important for parents to understand the difference between normal baby shakes and more serious issues. If you're concerned, it's recommended to consult a doctor and, if possible, record the movements to assist with assessment.

Newborns don't shiver from the cold

It is normal for newborns to make shivering movements, but this is not due to feeling cold. Older children and adults shiver when they are cold to generate heat through rapid muscle contractions and expansions. However, newborns have a different way of keeping themselves warm.

Newborns have a specific type of fat called brown adipose tissue, or brown fat, that helps to keep them warm. This type of fat burns calories and releases heat, acting like a scarf wrapped around the baby. Brown fat is found around the necks, chests, backs, and bottoms of newborns. While babies need to be dressed appropriately for cold weather, it is their brown fat, rather than shivering, that keeps them warm.

The presence of brown fat is one reason why it is important to monitor and control a baby's temperature with clothing and blankets. Newborns lose heat faster than older children and adults, and they cannot regulate their temperature by moving to a warmer place or adding layers.

The shuddering movements made by newborns are usually due to their developing muscles and slowly developing muscle control. These movements may occur when the baby gets excited, wants something, or moves in a certain way. They are also common when a baby is falling asleep or waking up and are known as myoclonus. Myoclonus can be frightening for parents to observe, but they are typically benign and will resolve within a year.

While most shivering movements in newborns are harmless, they can sometimes be a sign of something more serious, such as a seizure or low blood sugar. If the shaking lasts longer than 20 seconds, is associated with an injury, fever, or illness, or is accompanied by vomiting, loss of consciousness, unusual eye movements, or breathing difficulties, it is important to seek medical advice.

Shivering can be a sign of something sinister

While newborn babies do not shiver when they are cold, they can still make shuddering movements. These movements are usually harmless and are caused by the baby's developing muscles or in reaction to something. However, shivering can sometimes be a sign of something more serious.

Firstly, it is important to note that newborns do not shiver to generate heat, unlike older children and adults. Instead, newborns have a specific type of fat called brown adipose tissue, or brown fat, that burns and releases heat, keeping them warm. This is why it is crucial to monitor and control a baby's temperature with clothing and wraps, as they lose heat faster than older children and adults.

So, what could those shivering movements in newborns signify? On the one hand, they could be a normal part of the baby's development. Many babies exhibit jittery movements, especially when they are excited or want something. These movements are often short-lived and do not cause any disturbance to the baby. They may also occur as the baby falls asleep or wakes up, and they usually resolve within a year.

On the other hand, shivering in newborns can sometimes indicate a seizure or a more serious medical issue. Here are some signs that the shivering may be something sinister:

• If the shaking continues for longer than 20 seconds
• If it is associated with an injury, fever, or illness
• If it is accompanied by vomiting
• If there is a loss of consciousness
• If the baby is sleeping for unusually long periods afterwards
• If there are unusual eye movements
• If the baby's breathing has stopped
• If there is a noticeable change in the baby's facial expression, breathing, and heart rate
• If the movements are rhythmic and may occur on only one side of the body or are symmetric
• If the shaking is frequent, prolonged, and consistent, along with crying

If you observe any of these signs, it is important to seek medical advice and have the baby seen by a doctor. It can also be helpful to record the jittery movements on video, as this can assist medical practitioners in assessing the baby and differentiating between a seizure or benign movements.

Babies have a specific type of fat that keeps them warm

It is normal for newborns to not shiver when they are cold. Unlike older children and adults, babies have a specific type of fat called brown adipose tissue, or brown fat, that keeps them warm. This type of fat burns calories and releases heat, acting like a scarf wrapped around the baby's neck, chest, back, and butt.

Brown fat is a vital source of energy for newborns, helping them stay warm without needing to shiver. This is especially important during the first six months of life, after which babies typically start to shiver as a way to generate heat. While babies need to be dressed warmly when it's cold, their brown fat provides an additional layer of warmth.

The presence of brown fat in newborns is a fascinating example of how their bodies are specially adapted to meet their unique needs. This heat-generating tissue ensures that babies stay cosy and comfortable, even if they haven't yet developed the shivering reflex.

It's worth noting that while brown fat is crucial for warmth, babies do still need to be dressed appropriately for the weather. The American Academy of Pediatrics recommends that babies are dressed in one more layer than an adult would wear when it's cold, and in a wearable blanket or warm one-piece sleeper at night.

Shivering can be a sign of neonatal hypoglycaemia

Shivering is a mechanism that produces heat in the body when it is facing extreme cold. Shivering is inhibited when blood sugar levels fall between 30 and 45 mg/dL, to preserve energy for vital body functions, like brain activity and breathing.

Newborns do not shiver when they are cold. Instead, they have a specific type of fat called brown adipose tissue, or brown fat, that burns calories and releases heat. However, newborns can still experience shivering-like movements, such as jitters or trembling, which are usually harmless.

If a newborn is jittery when not crying, this could be a sign of hypoglycaemia, or low blood sugar. Hypoglycaemia is the most common metabolic disturbance occurring in newborns. It can be caused by poor nutrition for the mother during pregnancy, the mother having poorly controlled diabetes, incompatible blood types of mother and baby, or congenital metabolic diseases or hormone deficiencies.

Symptoms of hypoglycaemia in newborns include:

• Shakiness
• Blue tint to the skin
• Breathing and feeding problems
• Low body temperature (hypothermia)
• Floppy muscles (poor muscle tone)
• Lack of movement and energy (lethargy)

If you believe your baby is experiencing hypoglycaemia, seek medical advice.

Shivering can be a sign of a seizure

Shivering in newborns is not a typical response to cold temperatures. Instead, newborns possess a type of fat called brown adipose tissue, or brown fat, that burns calories and releases heat, thus keeping them warm. This is why newborn babies don't shiver when they are cold.

However, newborns do sometimes exhibit jittery movements, particularly when they are excited or agitated. While these movements may resemble shivering, they are usually benign and often occur as a result of developing muscles or in reaction to something. Nevertheless, in some cases, these jittery movements can be indicative of something more serious, such as a seizure.

There are several types of seizures that can occur in newborns, including:

• Febrile convulsion—a sudden change in body temperature.
• Convulsive seizures—stiffening and/or jerking movements of limbs.
• Tonic-clonic seizures—a sudden loss of awareness, causing the child to fall, followed by stiffening and then jerking of the muscles.
• Myoclonic seizures—sudden and brief muscle twitches that may involve the whole body or specific limbs or muscle groups.
• Atonic seizures—a sudden loss of muscle tone, which can cause the head to drop forward or even result in sudden collapse.
• Infantile spasms—a type of seizure with both focal and generalized features, typically beginning between three and six months of age, characterised by brief stiffening movements lasting one to two seconds each.

If you suspect your baby is experiencing a seizure, it is important to seek medical advice promptly. Additionally, consider videotaping the episode to assist medical practitioners in assessing and diagnosing the condition.

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