In the first weeks of life, a baby may twitch their arms and legs in short, rhythmic bursts during sleep, and sometimes the whole body shakes. Parents often fear it is a seizure. The most common explanation is benign neonatal sleep myoclonus: movements that happen during sleep in a healthy baby and are not caused by any brain disease. The key feature is that the twitching happens only during sleep and stops right away when you wake the baby.
What it looks like
It starts in the first week of life (in the medical literature, the median onset is day 7). The twitching can occur in any stage of sleep and lasts from a few seconds to a few minutes. It is often symmetrical and involves the arms more than the legs. Gentle rocking or a repeated sound can bring it on. A classic example is twitching that starts during a car ride or while you rock the baby in a cradle. When the baby wakes up, the movements end, and the baby feels fine, feeds well and develops normally for their age.
In a review of 24 publications covering 164 babies, 96% were healthy full-term infants. In about a third, the twitching continued after 3 months, but in most it disappeared completely by 6 months. In a Japanese study, it resolved by 6 months in 14 of 15 babies, and none went on to develop epilepsy.
How it differs from a seizure
| Feature | Sleep myoclonus | Seizure |
|---|---|---|
| When it happens | Only during sleep | Awake or asleep |
| When you wake the baby | Stops right away | Continues |
| When you hold the arm or leg | Does not stop, or gets stronger | — |
| Eyes, color | Normal | Eyes may roll; lips may turn blue |
| After the episode | Baby is normal | Limpness or vomiting may follow |
| EEG | Normal | Often shows changes |
The two most useful things for telling them apart are a video of the episode and a neurological exam of the baby. If doubt remains, a sleep EEG is done; in sleep myoclonus, the EEG is normal.
Why correct recognition matters
This condition is often misdiagnosed as “newborn seizures.” In one study, 15 of 18 babies had been treated with medication for seizures before they reached a neurologist, and all of the medication was stopped after the correct diagnosis. Anti-seizure medications do not improve sleep myoclonus and can even make it worse. In addition, some waves on the EEG that coincide with the twitching can be misleading when read without experience. So the diagnosis should rest on the clinical picture first, before the EEG.
What parents can do
- Record the episode on video: 20–30 seconds, with the baby’s face and limbs in view.
- Gently wake the baby and see whether the twitching stops.
- If the twitching happens while the baby is awake, or if you see eye rolling, a color change, refusal to feed or limpness, that is a different picture, so have the baby examined promptly.
- Bring the birth discharge summary to the visit. If the exam is normal and the episodes are typical, no medication or extra testing is needed, only follow-up.
This article is for educational purposes. If your baby has episodes of twitching, have them evaluated together with a pediatric neurologist: newborn neurological exam.
Scientific sources
The medical information on this page is based on the following peer-reviewed publications (PubMed).
- Maurer VO və b. (2010). Benign neonatal sleep myoclonus: a review of the literature Pediatrics. PMID 20351003
- Goraya JS və b. (2015). Benign neonatal sleep myoclonus: frequently misdiagnosed as neonatal seizures Indian Pediatr. PMID 26388639
- Suzuki Y və b. (2015). Benign neonatal sleep myoclonus: our experience of 15 Japanese cases Brain Dev. PMID 24750849
- Losito E və b. (2017). Benign Neonatal Sleep Myoclonus Evokes Somatosensory Responses J Clin Neurophysiol. PMID 28922194
Medically reviewed by: Dr. Aynura IbrahimovaLast updated:
The information on this page is for education only and does not replace an examination by a doctor. If you are worried about your child, book an appointment. In an emergency, call 103.