Self-limited Neonatal Convulsions

8th February 2021

A relatively uncommon syndrome, self-limited neonatal convulsions occurs in babies and young infants and initially presents with seizures which start in the first 28 days of life (the neonatal period). This syndrome was once informally known as ‘5th day fits’ as it often starts on the 5th day of life, although in reality can be anywhere from 3 to 14 days. This syndrome can affect both genders equally and has 2 types, famililal and non-familial. 

Self-limited familial neonatal convulsions is when another family member, usually a parent, has experienced similar convulsions. Many parents don’t recall these and can therefore be unaware they even had the syndrome. The reason for self-limiting familial neonatal convulsions is a genetic mutation found in chromosomes 8 and 20. 

Of course, self-limited familial neonatal convulsions is simply where there is no history of convulsions at a similar age within the family. 


The only real symptom of self-limited neonatal convulsions are the seizures themselves. The seizures can present in a number of ways: 

  • Cycling or punching movements of the upper and lower limbs. 
  • Jerking head movements followed by rhythmic jerking of one side of the body.
  • Brief periods when the baby stops breathing, at which time the face may turn red and the eyes may water. 
  • Tonic-clonic seizures, although this last one is rare within this syndrome


With the vast majority of the typical tests for epilepsy showing as normal, diagnosis of self-limited neonatal convulsions is very much reliant on a careful history taken by a doctor or specialist. The convulsions starting in the neonatal period is a key symptom that may lead to a correct diagnosis. 

With many other explanations for seizures during this time and other epilepsy syndromes to consider, diagnosis can be difficult. For this reason, a doctor will often have to rule out a number of other causes before they can confirm a diagnosis of self-limited neonatal convulsions. 

A blood test can be carried out to identify the genetic mutation, but this will only be found in babies with self-limited neonatal familial convulsions, and not those with the non-familial variant of the syndrome.


With self-limited neonatal convulsions treatment is often not necessary as the syndrome may only last for a few weeks. However, if medication is prescribed it will often be carbamazepine or sodium valproate and less commonly phenobarbital or phenytoin. If prescribed, these medications are often administered for 6 – 12 months at which point they are slowly discontinued over a period of time. 


The prognosis for self-limited neonatal convulsions is usually very positive. Many babies will only experience seizures for weeks or even a few days. More rarely, they can continue for a few months. Around 1 in 12 babies who have self-limited neonatal convulsions will go on to develop other seizures in late childhood or adulthood, but the risk of this is decreased with the non-familial variant of the syndrome. 

National Epilepsy Training can help

For more information and guidance on self-limited neonatal convulsions, speak to a member of our team. Call us on 01706 373075 or email