How Newborn Sleep Develops (And How Much Longer Until You Get More of It!)

New parents talk and think about sleep constantly. Newborn sleep is unpredictable,  and most new parents are desperate for more of it.  

You won’t get that blissful all-night sleep you enjoyed pre-baby during the first few months of your baby’s life,but you don’t have to be left wondering if you’ll ever sleep again!

Sleep patterns in newborns are constantly changing, faster in those first few months than at any other time. That unpredictability combined with sleep deprivation can feel overwhelming and discouraging. But there is good news! Even if you can’t predict how your baby will sleep tonight, we can predict how sleep patterns develop over time.

The development of newborn sleep falls into two categories: day sleep and night sleep. Day sleep (napping) doesn’t begin to consolidate into a reliable form until 4 months of age and won’t fully form until 6 months of age. This means your baby’s naps will be unpredictable, happening at different times and for different lengths each day for the immediate future

Don’t despair, though!  Night sleep develops rapidly in the first few months and will be more reliable long before day sleep. It improves day-by-day and week-by-week. As the weeks progress, so does your baby’s ability to sleep longer stretches at night–and your ability to get a decent night’s sleep.

0 to 4 weeks 

Newborn babies sleep a lot in the beginning; around 16-19 hours a day. It may not feel like they sleep all that much, based on how tired you are! That’s because this sleep typically happens in 2-3 hour chunks that are spread out over days and nights, which is pretty different from the preferred sleep schedule of most adults. As your baby grows, so will their ability to consolidate their night sleep into longer stretches.

Newborn sleep cycles consist of quiet (non-REM) and active (REM) sleep. Newborns spend 50% of their sleep in active sleep. The result: very noisy and fitful sleepers. Your baby may grunt, fuss, squirm, and even cry out loudly all while sleeping! Not every little noise and fuss needs intervention from parents. Wait a minute and give your baby space to work it out. If they really need you, they’ll let you know!

Takeaway: There is no clear sleep pattern detected during the first month. Babies will sleep on and off when needed over a 24 hour period, usually in 2-4 hour blocks of time. Your main goal at this stage is to establish good feeding habits, practice full feeds, and bond with your baby.

4-8 weeks

Get excited, because this is when night sleep begins to consolidate! Your baby will go through two important developmental changes that allow their night sleep to lengthen into longer blocks of sleep. First, their nervous systems begin to mature, allowing their circadian rhythms to fall into a day/night pattern. Second, their stomachs grow, allowing them to take in more milk each feed and drop a feed or two. More milk during the day means fewer feedings at night. 

At this age, your baby can do a 4-6 hour stretch of sleep at night. Some babies can even do 8 hours by 8 weeks. That first long stretch of night sleep feels like magic to tired new parents; enjoy it!  It’s important to know that full feeds are crucial to increasing the length of night sleep. If your baby only nibbles and snacks at feeding time, their belly won’t be full enough to get that longer sleep. 

Takeaway: During the second month of life, night sleep begins to consolidate and a baby who is taking in full feeds can sleep for a longer period of time, up to 8 hours.

8-12 weeks

Your  baby’s ability to sleep at night continues to grow, week by week. A consistent bedtime should start to emerge between about 7 and 8 pm, and baby’s first stretch of night sleep should be getting longer. The length of their longest block of night sleep should roughly correlate with their age:

• 8 weeks = 8 hours

• 9 weeks = 9 hours

• 10 weeks = 10 hours

• 11 weeks = 11 hours

• 12 week = 12 hours

By the time your baby hits 12 weeks of age, their circadian rhythms are fully developed and ready to be in sync with the rise and fall of the sun. Your baby can do 10-12 hours of sleep at night, assuming they’re taking in those full feeds during the day

Takeaway: By the time baby is 3 months old, she should have a consistent bedtime and be able to reliably sleep for most or all of the night. 

This doesn’t mean they will automatically do it, there are tips for that. But it does mean their bodies are ready for it.