Reasons for Sleepiness in a Baby

As a new parent, you might have prepared yourself for a lack of sleep when your baby arrived.

While you likely aren't well rested, you might find that your baby sleeps more than you expected.

Babies don't sleep for long intervals, but they do sleep often. Newborns often sleep from 14 to 18 hours a day. Babies can be sleepy for a number of reasons, and you should understand them so that you can identify any potential issues.

Making Adjustments

Your baby has been living comfortably in your warm, dark womb for the last nine months. Now, she is suddenly exposed to light, sounds and people who she does not know.

As she adjusts to the activity of the outside world, she will be particularly sleepy. In her first few weeks of life, a newborn might sleep up to 20 hours a day. This is normal, and if you have a little one adjusting to her life outside the womb, there's no cause for concern.


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Overstimulation can make even a normally alert baby extra tired. If your baby is having a particularly sleepy day, think about what you did earlier that day or the day before. Did he have more activity than normal? Perhaps you were at a family reunion where he was passed around and admired all day.

Or, maybe you missed his normal afternoon nap because you were out running errands.

Being overstimulated can cause exhaustion in babies. Let him nap as long as he wants to catch up on his sleep.


Babies receive vaccinations at 2, 4 and 6 months old, as directed by the American Academy of Pediatrics. A baby might be more sleepy than normal after she receives her vaccine.

A day or two of sleepiness is normal after vaccines and not a sign of a problem. However, if that sleepiness is combined with signs of a reaction, such as a seizure or significant swelling at the injection site, contact your pediatrician right away.


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If your newborn is diagnosed with jaundice after birth, he might be more tired than other babies. Jaundice, which is marked by yellowing of the skin and eyes, often goes away on its own and, if it does not, it is easily treatable. However, babies with severe cases of jaundice often experience extreme sleepiness.