Neonatal Seizures

Introduction

If your newborn has had a seizure, or is being investigated for possible seizures in the neonatal intensive care unit (NICU), you are likely facing a lot of unfamiliar words and difficult decisions at a very emotional time. This article is written for parents and families who are going through that experience. It explains what neonatal seizures are, what may have caused them, how doctors diagnose and treat them, and what to expect in the days, months, and years that follow.

Neonatal seizures — seizures that happen in the first 28 days of life — are different from seizures at any other age. The newborn brain is still developing, the signs can be very subtle, and the underlying causes are usually different from epilepsy in older children or adults. Most neonatal seizures are not a stand-alone problem but a signal that something is going on in the brain that needs to be identified and treated.

The good news is that neonatal seizures are taken extremely seriously by NICU teams. Pediatric neurologists, neonatologists, and specialist nurses work together to find the cause, control the seizures, and protect the baby’s developing brain. Outcomes vary widely depending on the cause, but many babies do well, and modern care has improved how quickly seizures are recognised and treated.

What Are Neonatal Seizures?

A seizure is a sudden burst of abnormal electrical activity in the brain. In adults and older children, seizures often cause obvious shaking or loss of consciousness. In newborns, seizures can look very different — sometimes so subtle that they are difficult to recognise without specialised brain monitoring.

The International League Against Epilepsy (ILAE) defines a neonatal seizure as a seizure occurring from birth through the first 28 days of life in a full-term baby, or through an equivalent corrected age in a preterm baby. Doctors usually divide neonatal seizures into clinical categories based on what the body does during the event:

• Subtle seizures — small movements such as repetitive lip smacking, sucking, chewing, eye deviation, eyelid fluttering, cycling movements of the legs, or brief pauses in breathing (apnoea). These are the most common type in newborns and the easiest to miss.
• Clonic seizures — rhythmic jerking of one limb, one side of the body, or multiple body parts. Unlike normal newborn jitteriness, the jerking does not stop when you gently hold the limb.
• Tonic seizures — sustained stiffening of part of the body, or of one side, sometimes with the eyes turning to one side.
• Myoclonic seizures — sudden, brief, lightning-like jerks, often of the arms.
• Electrographic-only seizures — seizures that show up on the EEG (a brain-wave test) but produce no visible movement. These are common in newborns, particularly after the first dose of seizure medication, which can hide the outward signs while electrical seizures continue in the brain.

Because so many neonatal seizures are subtle or electrographic-only, NICU teams rely heavily on continuous EEG monitoring rather than just watching the baby. This is one of the most important differences between neonatal seizures and seizures at older ages.

Neonatal Seizures Are Not the Same as Epilepsy

Many parents understandably worry that a seizure in the newborn period means their child has epilepsy. In most cases, that is not the right way to think about it. Epilepsy is a condition of having an ongoing tendency to seizures. Neonatal seizures, in contrast, are usually acute symptomatic seizures — meaning they are caused by a specific event affecting the brain (such as a lack of oxygen at birth, an infection, a stroke, or a temporary chemical imbalance) and often stop once the underlying problem is treated.

A smaller group of babies do have what doctors call neonatal-onset epilepsy, where seizures continue beyond the immediate trigger and represent a longer-term condition, sometimes due to a genetic cause or a structural difference in the brain. Distinguishing acute symptomatic seizures from neonatal-onset epilepsy is an important part of the diagnostic work-up.

Causes and Risk Factors

Neonatal seizures are almost always a symptom of something else happening in the brain. Identifying the cause is just as important as stopping the seizures, because the treatment and outlook depend heavily on what is driving them.

Hypoxic-Ischaemic Encephalopathy (HIE)

The single most common cause of neonatal seizures in full-term babies worldwide is hypoxic-ischaemic encephalopathy — brain injury due to reduced oxygen and blood flow around the time of birth. This may follow a difficult delivery, a problem with the placenta, or other events that interrupt the baby’s oxygen supply. Seizures from HIE typically appear within the first 24 to 72 hours after birth.

Stroke in the Newborn

Newborns can have strokes — a blocked or bled blood vessel in the brain — even when they appear healthy at birth. Neonatal stroke often presents as seizures involving one side of the body in an otherwise well-looking baby in the first few days of life. MRI scanning is used to confirm the diagnosis.

Brain Bleeds (Intracranial Haemorrhage)

Bleeding in or around the brain can trigger seizures. This is more common in premature babies but can happen at any gestation, including after a traumatic delivery.

Infections

Infections of the brain or surrounding membranes — meningitis and encephalitis — are important causes of neonatal seizures. These can be caused by bacteria (such as group B streptococcus or E. coli), viruses (such as herpes simplex), or, less commonly, parasites or fungi. Some infections acquired before birth, such as cytomegalovirus or toxoplasmosis, can also cause seizures.

Metabolic and Chemical Imbalances

Several treatable chemical imbalances can cause seizures in newborns:

• Low blood sugar (hypoglycaemia) — particularly in babies of mothers with diabetes, small or preterm babies, or babies with feeding problems
• Low blood calcium (hypocalcaemia) or low magnesium
• Low sodium (hyponatraemia)
• Inborn errors of metabolism — rare inherited conditions in which the body cannot process certain proteins, sugars, or fats correctly, leading to a build-up of substances that can damage the brain
• Pyridoxine (vitamin B6) dependency — a rare condition in which seizures respond only to vitamin B6

Because some of these causes are highly treatable, NICU teams routinely check blood tests early in the work-up.

Structural Brain Differences

Some babies are born with differences in how the brain formed during pregnancy — for example, areas where the brain cortex developed abnormally. These differences may be visible on MRI and can be associated with seizures and longer-term epilepsy.

Genetic Causes

Genetic changes in certain genes can cause neonatal-onset epilepsy syndromes. Some of these are self-limited (the seizures stop within months and the child develops normally), while others are more severe and may be associated with developmental difficulties. Genetic testing is increasingly used when no clear acquired cause is found.

Drug Withdrawal

Babies exposed to certain medications or substances during pregnancy may have seizures as part of withdrawal in the first days or weeks of life. The neonatal team will usually ask about medication and substance exposure during the work-up.

How Neonatal Seizures Are Recognised

Recognising seizures in newborns is not straightforward, even for experienced clinicians. Newborns often make jerky, unusual movements that are completely normal — this is called jitteriness. Things that distinguish a seizure from jitteriness include:

• The movement does not stop when you gently hold or reposition the limb
• The movement is not triggered by a startle or by handling the baby
• Eye movements (such as fixed staring or deviation to one side) accompany the movement
• There may be changes in heart rate, breathing, blood pressure, or skin colour

If you are with your baby and notice something that worries you, telling the nurse or doctor immediately is always appropriate. Even very experienced parents and clinicians sometimes cannot tell from the outside whether an event is a seizure — which is why the EEG is so important.

Diagnosis

The diagnostic process has two goals: to confirm whether the events are truly seizures, and to find out what is causing them.

EEG and Continuous Video-EEG Monitoring

• Confirm whether unusual movements are actually seizures
• Detect electrographic seizures that produce no visible signs
• Measure how often seizures are occurring (the “seizure burden”)
• Assess how well treatment is working

The American Clinical Neurophysiology Society and major pediatric neurology bodies recommend continuous video-EEG monitoring as the standard for diagnosing and managing neonatal seizures. In NICUs where this is not available 24 hours a day, a simpler tool called amplitude-integrated EEG (aEEG) is often used at the bedside as a screening monitor, with full EEG performed when possible.

Brain Imaging

Imaging helps identify a cause. Two main types are used:

• Cranial ultrasound — a quick, gentle bedside scan that can detect bleeds and major structural problems, often used as a first look in preterm babies
• MRI (magnetic resonance imaging) — more detailed; can show stroke, HIE, infection, bleeds, and developmental brain differences. MRI is generally the preferred imaging test for evaluating a cause when the baby is stable enough to be moved to the scanner.

A CT scan may occasionally be used if MRI is not available or in specific emergency situations.

Blood and Other Laboratory Tests

A wide panel of blood tests is usually done to look for treatable causes, including blood glucose, calcium, magnesium, sodium, infection markers, ammonia, lactate, and tests for inborn errors of metabolism. A lumbar puncture (spinal tap) may be performed to test the cerebrospinal fluid for infection or other markers.

Genetic Testing

When the cause is not obvious from clinical history, imaging, and metabolic tests — particularly if seizures continue or are difficult to control — genetic testing may be offered. This can include a focused epilepsy gene panel or broader whole-exome sequencing. Genetic results can take days to weeks but sometimes identify a specific syndrome that changes treatment decisions.

Treatment in the NICU

Treatment of neonatal seizures has two parts that happen in parallel: stopping the seizures, and treating whatever is causing them.

Treating the Underlying Cause

Many causes have specific treatments that, once started, may stop the seizures from the inside:

• Therapeutic hypothermia (cooling) for babies with moderate to severe HIE — the baby’s body temperature is carefully lowered for 72 hours, then slowly rewarmed. This treatment is supported by major pediatric and neonatal societies as the standard of care for eligible babies, and has been shown to reduce death and disability.
• Glucose, calcium, or magnesium infusions to correct metabolic imbalances
• Antibiotics or antivirals for infections — for example, intravenous aciclovir if neonatal herpes is suspected
• Pyridoxine (vitamin B6) trial when vitamin-responsive seizures are suspected
• Specific dietary or metabolic treatment when an inborn error of metabolism is identified

Anti-seizure Medications

• Phenobarbital — has been the most widely used first-line medication for decades. Current international guidance, including the ILAE/WHO recommendations on neonatal seizures, continues to support phenobarbital as the first medication for most babies because of the larger body of evidence in newborns, while acknowledging that it is not always effective and has its own side effects.
• Phenytoin or fosphenytoin — often used as a second-line medication if phenobarbital does not stop the seizures
• Levetiracetam — increasingly used in some centres as a first or second-line option, particularly because of its favourable side-effect profile, although in head-to-head trials in newborns it has shown lower effectiveness than phenobarbital. Its role is still evolving.
• Midazolam or lidocaine — may be used as additional treatment when seizures continue despite first and second-line medications

The team will continue to monitor with EEG to check that seizures have stopped — not just visibly, but electrically — before deciding whether more medication is needed.

When Seizures Are Difficult to Control

If seizures continue despite multiple medications, the team will reconsider the cause. They may repeat imaging, send further genetic or metabolic tests, or trial specific therapies such as the ketogenic diet in selected situations. A baby with very difficult-to-control seizures may be cared for by a specialist neonatal neurology team.

Risks and What to Watch For

Seizures themselves, if frequent or prolonged, may add to brain injury — on top of whatever caused the seizures in the first place. This is one reason NICU teams treat seizures aggressively, even when they do not produce visible movements.

Risks of the medications used include sleepiness, slowed breathing, low blood pressure, and possible effects on the developing brain. These are weighed against the risks of continuing seizures. The team usually aims to use the lowest effective dose and to stop medication as soon as is safely possible.

As a parent, the most useful things you can do during the NICU stay include:

• Ask the team to describe what they are seeing on EEG and what the current treatment plan is
• Tell the nurses about any movements or events that worry you, even if you are not sure
• Spend time with your baby — touch, voice, and (when appropriate) skin-to-skin contact are valuable, and the team will tell you what is safe at each stage
• Take care of yourself — rest, food, and emotional support are not optional during a long NICU stay

After Seizures Stop: The Next Steps

Stopping Anti-seizure Medication

Once seizures have been controlled for a period of time and the underlying cause is treated or stable, many teams begin to reduce or stop anti-seizure medication before the baby goes home. Current pediatric neurology practice in many centres — supported by ILAE guidance — is to discontinue anti-seizure medication relatively early when neonatal seizures were due to an acute symptomatic cause and the neurological examination and EEG have improved. This approach reflects evidence that prolonged exposure to these medications may itself have effects on the developing brain, and that many acute symptomatic seizures do not recur once the cause is resolved.

In other situations — particularly when the cause is a structural brain difference, a genetic epilepsy, or when seizures are difficult to control — medication may be continued at discharge, with a plan to reassess over the coming months.

Hospital Discharge

Going home from the NICU is a major milestone. Before discharge, the team will usually arrange:

• A discharge summary explaining what happened, what treatment was given, and what to do at home
• Follow-up appointments with the pediatrician, pediatric neurologist, and any other specialists involved
• An early intervention or developmental follow-up referral, particularly if the cause was HIE, stroke, infection, or a structural brain difference
• Information on what a seizure might look like at home, and when to seek urgent care
• Feeding and growth monitoring plans, since babies who have been in the NICU sometimes need extra support with feeding

Long-term Outlook

Possible Outcomes

• Full recovery — many babies whose seizures were due to a treatable, transient cause (such as a corrected metabolic imbalance or a self-limited genetic syndrome) go on to develop normally with no lasting effects.
• Later epilepsy — a proportion of children who had neonatal seizures will develop epilepsy at some point in childhood. The risk is higher when the cause involved significant brain injury or a structural or genetic abnormality, and lower when the cause was a fully reversible problem.
• Developmental differences — some children have delays or difficulties in areas such as movement, learning, speech, or behaviour. These are usually related to the underlying brain injury or condition rather than to the seizures alone. Cerebral palsy is a possible outcome after significant HIE or stroke.
• Mixed pictures — many children have outcomes that fall in between, with strengths in some areas and challenges in others.

Predicting outcomes is most reliable when several pieces of information are combined: the cause of the seizures, the findings on MRI, how the baby’s neurological examination looks at discharge, and how development progresses in the first months. Your pediatric neurologist is the best person to discuss what is and is not known in your child’s individual case.

Developmental Follow-up

Most children who have had neonatal seizures are followed regularly in the first years of life. Follow-up typically includes:

• Pediatric neurology review — assessing neurological development and any signs of recurring seizures
• Developmental assessment — checking motor skills, language, social development, and learning
• Early intervention services — physiotherapy, occupational therapy, and speech-language therapy where helpful
• Hearing and vision testing — particularly important after HIE, infections, or significant prematurity
• Repeat EEG and MRI — only if clinically indicated, not routinely

Recognising a Seizure at Home

Once your baby is home, it can be hard to know whether an unusual movement is a seizure or normal newborn behaviour. Things that should prompt you to contact your team include:

• Rhythmic jerking of an arm, leg, or one side of the body that does not stop when you hold the limb
• Sustained stiffening of the body, particularly with eye deviation
• Repetitive, unusual movements such as cycling of the legs or repeated lip smacking that cannot be interrupted
• Episodes of staring with unresponsiveness
• Pauses in breathing with a colour change, especially if accompanied by any of the above
• Any event that simply feels different and worrying to you

If you can, record a video on your phone — this is one of the most useful things a parent can do, because it lets the doctor see exactly what happened. If your baby has a clearly prolonged seizure (longer than a few minutes), repeated seizures, or is unresponsive between events, this is an emergency and you should seek immediate medical care.

Supporting Yourself and Your Family

Going through neonatal seizures is one of the harder things a family can experience. Parents often describe a mix of fear, guilt, exhaustion, and grief — sometimes alongside hope and gratitude. None of these feelings are wrong.

A few things parents and families have found helpful:

• Ask questions until you understand the answers, and ask the same question again later if you need to — medical teams expect this
• Keep your own notes or a simple diary of what is happening; this helps both at the time and at later appointments
• Accept practical help from family or friends — meals, transport, looking after older siblings
• Connect with parent support organisations for neonatal intensive care, HIE, stroke, or epilepsy, depending on your situation; speaking with other parents who have been through similar experiences can be powerful
• Talk to a mental health professional if you are struggling — postnatal mental health support is part of caring for your baby, not separate from it

Siblings and partners are also affected and may need their own space to talk about what is happening. Many NICUs have social workers or family support staff who can help with this.

Frequently Asked Questions

Will my baby develop epilepsy later?

Not all babies who had neonatal seizures develop epilepsy. The risk depends heavily on the cause and on the findings of the MRI and EEG. Babies with seizures due to a fully reversible cause and a normal MRI are much less likely to develop epilepsy than babies with a structural brain difference or a genetic epilepsy syndrome. Your pediatric neurologist can give you a clearer picture based on your child’s individual findings.

Did anything I did during pregnancy cause this?

For the great majority of neonatal seizures, the answer is no. Causes such as HIE, neonatal stroke, infections, and genetic conditions are not the result of anything a parent did or did not do. If you are worried about a specific exposure during pregnancy, the medical team can review it with you honestly.

How long will my baby be on seizure medication?

This varies. For babies whose seizures were due to a transient acute cause, many teams stop medication before or shortly after discharge, in line with current ILAE guidance. For babies with ongoing risk of seizures — for example, due to a structural brain difference or a genetic epilepsy — medication may continue for longer, with regular review.

Will the seizure medication harm my baby’s brain?

This is an important question that pediatric neurologists take seriously. Anti-seizure medications can have effects on the developing brain, which is part of why teams aim to use them for the shortest time necessary. At the same time, untreated seizures themselves can also harm the brain. The decision is always a balance, made with your baby’s specific situation in mind.

Can I breastfeed if my baby is on anti-seizure medication?

In most situations, yes. Breastfeeding is generally encouraged and is compatible with the common anti-seizure medications used in newborns. Your team can give you specific advice. If your baby is too unwell to feed directly at first, expressed breast milk can often be given.

Does therapeutic hypothermia (cooling) hurt my baby?

Cooling is carefully managed and the babies are kept comfortable. The aim is to gently lower body temperature by a few degrees for a defined period, which has been shown to reduce brain injury in eligible babies with HIE. The team monitors the baby closely throughout and uses sedation or comfort measures as needed.

Is it safe to hold and bond with my baby in the NICU?

In most cases, yes — and it is encouraged when the baby is stable enough. Even during cooling or while on monitoring, the team will help you find ways to touch, talk to, and be present with your baby. Skin-to-skin contact (kangaroo care) is usually possible at some stage and has benefits for both baby and parents.

If we have another baby, will the same thing happen?

The risk of recurrence depends entirely on the cause. Most causes — such as HIE, neonatal stroke, or infections — are not likely to recur in a future pregnancy. Genetic causes carry a recurrence risk that depends on the specific gene and inheritance pattern; a genetic counsellor can give you accurate information once a diagnosis is known.

Are home video monitors useful?

Movement and breathing monitors marketed for home use are not designed to detect seizures and should not be relied on for this. If you are worried about events happening at home, recording them on your phone when they occur and sharing the videos with your team is far more useful than a continuous home monitor.

Conclusion

Neonatal seizures are a serious event but also one that pediatric neurology and neonatal teams are well-prepared to address. The journey usually involves three intertwined tasks: stopping the seizures, finding and treating the cause, and supporting the baby’s development over the months and years that follow. Each of these has seen real progress in recent decades, including better EEG monitoring in the NICU, cooling for eligible babies with HIE, more refined use of anti-seizure medications, and earlier, more accurate diagnosis through imaging and genetic testing.

The most important thing for families to know is that the outlook depends on the underlying cause, not on the word “seizure” alone. Many babies do well. Others face longer journeys with developmental support, ongoing medication, or both. In all cases, an experienced pediatric neurology team working with the family is the foundation of good care, and early developmental follow-up gives every child the best chance to grow into their full potential.