Why do babies need so much sleep?

If you ask a new parent what topic is at the top of their minds, there’s a pretty good chance that the answer would be ‘sleep’. When you’re the parent of a newborn or infant, you suddenly end up focusing far more on sleep than you did previously. While childless, you pretty much take sleep for granted, but it’s an entirely different story once you have a child.

If you haven’t been around newborns much, it might shock you how much a baby needs to sleep. For some parents, their baby won’t sleep whatsoever. It’s common for a baby in the first few weeks of their life to sleep for as many as 17 hours per day. And to make matters even stranger, newborns usually sleep in short doses, waking up after only an hour or two asleep.

Many parents find themselves wondering why babies sleep so much. The answer has to do with how newborns and infants develop, and the natural lifecycle of a baby. But the short answer is that everything is normal if your baby is sleeping a huge percentage of each day.

As a new parent, it’s almost alarming how capable babies are of sleeping nearly all day and all night long. You might be wondering how babies can sleep so much in the first place. After all, you wouldn’t be able to sleep 15 hours in a day if you tried.

The reason why babies sleep so much has to do with the fact that newborns really only have one job to do: Grow bigger and thrive.

Sleep Equals Growth

When a baby is first born, it’s basically helpless. A newborn baby is fragile and incapable of even the simplest of coordinated movements. In order to be able to do more, a newborn needs to get bigger and stronger.

To make that happen, the newborn baby’s body prioritizes growing at the expense of nearly anything else. This means taking in the right amount of breast milk and formula and then turning that food into growth.

Sleeping is a time when newborns experience the majority of this growth. While we associate sleeping in our adult lives with rest or recharging, your newborn is actually working as hard as they ever work while sleeping. During sleep, a baby is turning energy from food into new bone mass, muscles, fat, tendons and everything else they need to grow bigger. The reason why babies sleep so much is that it helps them grow and develop.

Sleep Expectations for Babies

The first month of a newborn’s life is the period during which they should sleep the most. As they grow older, you’ll start to see that sleep time gradually decrease. Here are some benchmarks in terms of sleep times and what to expect with your baby’s sleep schedule.

  • Newborn to 1 month: 15-17 hours of sleep. Around 7-9 hours during the night, 8 hours during the day.
  • 1 month to 3 months: 14-16 hours of sleep. Around 7-9 during the night, 6-7 hours during the day.
  • 3 months to 6 months: 13-16 hours of sleep. Around 8-10 during the night, 4-6 during the day.
  • 6 months to 9 months: 12-15 hours of sleep. Around 9-10 during the night, 3-5 during the day.
  • 9 months to a year: 12-15 hours of sleep. Around 10-11 during the night, 3-4 during the day.
  • 1 year to 1 1/2 years: 12-14 hours of sleep. Around 10-11 during the night, 2-3 during the day.
  • 1 1/2 years to 2 years: 12-14 hours of sleep. Around 10-11 during the night, 1-3 during the day.

When taking a look at the above sleep schedule, it’s important to keep a few things in mind.

First of all, the above represent ranges, and it’s even possible for some babies to fall slightly outside these ranges and still be perfectly healthy. Every baby is different, and this is definitely the case when it comes to sleeping.

If you’re worried about your baby sleeping either too much or not enough, the first thing you should do is check the above sleep schedule ranges to see if your baby falls into the appropriate range. If so, you have nothing to worry about. The reason why your babies sleep so much compared with other babies might simply be a slightly different internal sleep schedule.

If your baby is outside those ranges, this still might be nothing to worry about. But in that case, you can consult your pediatrician to see if you need to look into it further.

Another thing you’ll notice in that schedule is the fact that your baby starts out sleeping quite a bit during the day, and gradually cuts back on that daytime sleeping. This too is perfectly normal, even if it can sometimes be frustrating for a parent.

Day and Night Cycles and Baby Sleep Patterns

On typical complaint from moms and dads is how much a baby sleeps during the day and is up during the night. As adults, we’ve developed circadian rhythms, and newborn babies don’t have them yet. This is why babies sleep so much during the daytime early in their life.

Circadian Rhythms and Sleep Patterns

Have you ever noticed that you tend to get drowsy at similar times each day, or tend to have periods off time where you’re at your most energetic? Circadian rhythms are the reason you feel this way.

Your circadian rhythm essentially acts as a 24-hour-long internal clock for your body. It regulates your energy patterns to cause you to feel either sleepier or more alert at different times over the day.

Usually, you feel your circadian rhythm most noticeably when you’re not fully caught up on your sleep, but your circadian rhythm is always functioning. It’s affected by things like light and darkness, and it changes gradually as you age.

The bottom line is that our bodies are programmed to want to sleep during the night and be awake during the day. But babies are born lacking a circadian rhythm.

It takes months for a baby to start to get used to sleeping more during the night than the day. And when a baby is first born, that kind of baby sleep schedule is missing entirely. In fact, there are some babies who are born more prone to sleeping during the day and being awake for a greater portion of the night.

This can be a great source of frustration for parents, who wonder why babies sleep so much during the day. Some parents even attempt to keep their babies awake during the day, hoping they will sleep more during the night to compensate. This is not a good idea, however.

Baby Sleep Intervals

A newborn baby is likely to only sleep for 1-2 hours at a time, waking frequently and then falling back asleep after a short interval. Over time, these sleep intervals start to stretch out longer, becoming 2-3 hour intervals, up into 3-4 and finally into longer blocs of sleep centered more on night time.

Again, there’s absolutely nothing wrong with your baby initially sleeping in short bursts. While you may wonder why should babies sleep so much but in such small doses, the short answer is that this is how babies are set up to sleep when they’re first born.

It’s far more convenient for a baby to sleep during the night when you as a parent are predisposed to sleep too. And when you see your baby sleep for multiple hours during the day and then wake up during the night, it makes sense to think that if your baby were sleeping less during the day, they’d sleep more at night.

But the problem with this thinking is that a newborn baby needs to sleep and wake up over short intervals. There’s no magical way to make a newborn sleep for a six-hour bloc. By preventing your baby from sleeping during the day, there’s a chance you could be stunting their development by depriving them or much-needed sleep. After all, the reason why babies sleep so much is that it’s healthy to do so. Depriving them of that sleep is the very opposite of healthy.

And during the night, your newborn is still going to wake up frequently. As frustrating as it may be, being a parent or caretaker of a newborn means dealing with sleepless nights. The good news is that as a baby grows older, the sleep intervals start to smooth out and the amount of time they’re sleeping during the day decreases.

By the age of two or so, your infant should be mostly sleeping at night, with no more than a nap or two needed during the day.

Conclusion

As a new parent, you might be wondering why babies sleep so much compared with adults or even older children. And as a repeat parent, you might find that your second child sleeps more than the first. This might cause you alarm, wondering why babies may sleep so much even in comparison to other babies.

The truth is that the reason why babies sleep so much is that they’re using that sleep time to grow bigger at a critical time in their development. And not every baby is the same, meaning any given newborn may fall differently within a healthy sleep schedule range.

The number one focus should be on your baby’s health and growth patterns. If your baby is healthy and growing at a normal pace, there’s nothing wrong with your baby sleeping long hours during both day and night.