Sleep with eyes open in newborns

Sleep with eyes open in newborns: A normal, though strange phenomenon

When parents see their newborn sleeping with partially or fully open eyes, it can cause surprise and even concern. This phenomenon, known in medicine as фізіологічний лагофтальм сну, is actually quite common and in the vast majority of cases completely normal for infants. It is related to the particular structure of their sleep.

Main cause: Active sleep phase

A newborn’s sleep consists of two main phases: active (rapid eye movement, REM) and quiet (deep sleep). Unlike adults, newborns spend up to 50% of their total sleep time in the active phase. This phase, essential for intensive brain development, is characterized by high activity:

• Rapid eye movements (REM): The eyeballs move actively under the eyelids.
• Restless movements: The baby may twitch, move arms and legs.
• Facial activity: Smiles, grimaces, sucking motions.

During this active phase, muscle control is not complete. The muscles responsible for closing the eyelids may not be fully relaxed, which leads to the eyes remaining partially open. Often you can even see the eyeballs moving under the lids. This is merely an external manifestation of intense brain activity. More details about this phenomenon can be read in the article "Physiology of newborn sleep".

When should you consult a doctor?

Although it is usually normal, there are a few rare situations that warrant attention:

• If the eyes stay open continuously, not just episodically during sleep.
• If you notice the child’s eyes appear dry, red, or irritated.
• If it is accompanied by other neurological symptoms or eyelid problems.

In such cases, a doctor can check for congenital eyelid anomalies or other conditions. But for most infants, sleep with eyes open is simply another strange yet safe feature of the first months of life.