Shivering Newborns: What's Normal And What's Not?

Newborns often exhibit strange behaviours, and one of them is shivering. While it is natural to worry about your baby's well-being, newborn shivering is usually not a cause for concern. Newborns do not shiver due to cold temperatures; instead, they rely on a layer of 'brown fat' to generate heat. Shivering in newborns is often attributed to their immature nervous system, which causes jerky and twitchy movements. These movements tend to become more fluid by the time the baby is one to two months old. Additionally, newborns may shudder when they get excited, want something, or move in any way due to their slowly developing muscle control. While most cases of newborn shivering are harmless, it is important to monitor your baby's overall behaviour and consult a doctor if you notice any sudden changes or if the shivering lasts longer than 20 seconds.

Shivering newborns: Is it normal jitteriness or a sign of low glucose?

Shivering in newborns is a common concern for parents. While it is often a normal part of their development, it can also be a sign of an underlying condition such as low blood glucose or hypoglycaemia. So, how can you tell the difference? This article will explore the causes of newborn shivering and provide guidance on when to seek medical advice.

Normal Jitteriness

Newborns have an immature nervous system, which can cause jerky and twitchy movements, particularly when they are crying, falling asleep, or waking up. This is known as normal jitteriness or trembling and usually stops by one to two months of age. It can be a result of the Moro or startle reflex, which is triggered by loud noises or other sudden stimuli and typically occurs until the baby is three to six months old. These movements are generally harmless and will stop once the baby's nervous system matures.

Shivering and Low Glucose

On the other hand, shivering can be a sign of low blood glucose or hypoglycaemia in newborns. Glucose is the main source of fuel for the brain and body, and a drop in glucose levels can cause problems such as shakiness, blue-tinted skin, and breathing and feeding difficulties. Hypoglycaemia can occur due to various factors, including maternal diabetes, poor maternal nutrition during pregnancy, incompatible blood types between mother and baby, and congenital metabolic diseases. Newborns with risk factors for hypoglycaemia, such as preterm birth or maternal diabetes, should be closely monitored by healthcare professionals.

When to Seek Medical Advice

If you are concerned about your newborn's shivering, it is important to seek medical advice. While normal jitteriness should resolve within the first few months, persistent or frequent shivering may be a sign of low glucose or another underlying condition. A simple blood test can diagnose hypoglycaemia, and treatment options include providing the baby with a fast-acting source of glucose through feeding or intravenously. Additionally, if you suspect your baby is having seizures, characterised by muscle jerking, eye blinking, and unresponsiveness, contact your healthcare provider immediately.

What is Infant Shudder Syndrome and how is it different from seizures?

Infant Shudder Syndrome (ISS) is a condition that involves infants rapidly shivering in the upper chest, shoulders, neck, and head. Babies with ISS may exhibit symptoms several times a day, with some cases reporting shuddering attacks up to 100 times per day. While the attacks typically last only a few seconds, they can be distressing for parents. ISS usually occurs following a difficult birth and can be a sign of cerebral palsy caused by oxygen deprivation during or shortly after birth. While some doctors believe that ISS is not indicative of a serious condition, others argue that it could be a sign of an illness or brain disorder, especially if the infant has other underlying conditions.

Seizures, on the other hand, are a different phenomenon that requires medical attention. They can be a symptom of a brain injury or illness and may appear similar to ISS, with slight tremors in the baby's upper body lasting a few seconds. However, seizures can also be more violent and last longer, indicating an underlying issue beyond ISS. During a seizure, a child may stare straight ahead without showing any emotion and may be unresponsive. After a seizure, the child may seem excessively tired.

The key differences between ISS and seizures lie in the duration, frequency, and behavioural changes. ISS attacks typically last a few seconds and occur several times a day, whereas seizures can last longer and be more violent. Additionally, infants experiencing ISS do not lose their ability to interact with others and do not feel tired or groggy after an attack, whereas children experiencing seizures may become unresponsive and seem tired afterwards.

If you suspect your baby is experiencing ISS or seizures, it is important to consult a doctor, especially a neurologist, for further evaluation and to rule out any serious underlying conditions.

Why do newborns shiver when they're not cold?

Shivering in newborns is often misinterpreted as a sign of cold. However, newborns do not shiver because they are cold. Instead, they rely on a layer of 'brown fat' or adipose tissue, which burns off and generates heat. This is because newborns have a problem with thermoregulation, or keeping a normal body temperature.

Newborns may shiver due to low blood sugar or hypoglycemia, which can be life-threatening. If you see a newborn shivering, it needs to be fed immediately. Shivering may also be caused by a surge in adrenaline.

Newborns also have a still-developing neurological system, which can cause a newborn's chin to quiver or legs to tremble. As the baby's nervous system matures, these movements will become more fluid.

Another reason for shivering or shuddering movements in newborns is due to their slowly developing muscle control. Newborns will often shudder their limbs when they get excited, want something, or move in any way. These movements can sometimes be misinterpreted as seizures.

If you are concerned about a newborn's shivering, it is recommended to record a video to show to your doctor.

How to know if a newborn is having a seizure

Shivering in newborns is usually nothing to worry about. It is often simply a result of an immature nervous system, which will resolve itself within a couple of months. However, in some cases, shivering can be a sign of a more serious condition, such as cerebral palsy caused by oxygen deprivation during birth.

Signs of Seizures in Newborns

Seizures in newborns are different from those in older children and adults. They can be difficult to recognise, even for medical professionals and parents. However, it is important to be able to identify them, as they can be a symptom of a brain injury or illness, and can cause permanent damage if left untreated.

The following signs may indicate that a newborn is experiencing a seizure:

• Movements and behaviours that are not typical for their age
• Repeated episodes with identical features and duration
• Episodes that are not brought on by changes in posture or activity
• Noticeable changes in the baby's facial expression, breathing, and heart rate
• Rhythmic movements that may occur on one side of the body, or are symmetric (both arms doing the same thing, for example)
• Shaking or jerking that cannot be stopped by holding the relevant body part
• Random and abrupt pauses in activity, with the eyes gazing slightly to the side
• Sudden tonic posturing, where the forearms are held flexed or extended for several seconds
• Generalised convulsing is rare in infants. Instead, look out for focal seizures and epileptic spasms, which may occur in clusters for several minutes when the baby first wakes up or is going to sleep. The baby may appear calm or cry between spasms, and they will likely occur every day.

What to Do if You Suspect a Seizure

If you think your baby might be having seizures, you should contact your doctor immediately. It can be helpful to record the suspicious activity and bring the video to your doctor to review. Your doctor will be able to put your mind at rest, or recommend the proper treatment if it is indeed more than normal baby movements.

Causes of Seizures in Newborns

Seizures are often a symptom of a more serious underlying condition, particularly a brain injury. They can also be caused by:

• Lack of oxygen before or during birth
• Infection acquired before or after birth
• Stroke before or after birth
• Blood clot in the brain
• Bleeding in the brain
• Blood sugar or electrolyte imbalances
• Metabolic disorders
• Drug withdrawal, which may affect babies born to mothers with substance use disorder

What to do if your newborn is shivering

Shivering in newborns is usually harmless and caused by an immature nervous system. However, if you notice your newborn is shivering, there are a few things you should do to ensure their comfort and safety:

• Keep them warm: Wrap your baby securely in a blanket to ensure they are not shivering due to being cold.
• Monitor their blood sugar: Shivering can be caused by low blood sugar levels. If your baby shows other signs of hypoglycaemia, such as a blue tint to the skin or lips, lethargy, or a lack of interest in feeding, contact your baby's pediatrician or healthcare provider.
• Reduce stress: Try to calm your baby and reduce their heart rate by removing them from stressful situations.
• Feed your baby: Shivering can be caused by a surge of adrenaline, so feeding your baby may help to reduce this.
• Record the incident: If you are concerned, record the shivering incident on video to show to your baby's doctor.
• Contact your doctor: If you are worried that the shivering could be a seizure, contact your doctor immediately. Seizures can be a symptom of a brain injury or illness. Signs of a seizure include muscle jerking, blinking, sucking movements, and a noticeable change in facial expression, breathing, and heart rate.

Remember, while newborn shivering is usually harmless, it is always best to consult your doctor if you have any concerns about your baby's health.

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