Understanding the science of newborn sleep can seem like a mystery. For new parents, one of the biggest challenges is figuring out why their newborn sleeps so much yet wakes frequently, seemingly without a clear pattern.
Sleep deprivation can be tough for parents, but the good news is newborn sleep behaviors, while unpredictable, are normal. This guide will explain the science behind why newborns sleep the way they do, what their sleep cycles look like, how you can gently guide them into a sleep routine, and what you can expect as your baby grows. Let’s dive into the world of newborn sleep and the tools to understand your baby’s sleep needs.
Why Do Newborns Sleep So Much?
A newborn’s body is hard at work even when they seem to be resting. A newborn sleep takes 14–17 hours, which is crucial for their rapid development. Sleep helps with physical and mental growth, supporting processes like:
- Brain Development: Your baby’s brain grows fast during the early months. Sleep is critical for building the neural connections that allow your baby to learn, process sensory input, and develop cognitive skills. During sleep, the brain strengthens the pathways that are formed during wakeful periods, and this is particularly true during REM (rapid eye movement) sleep.
- Physical Growth: Babies don’t grow when they’re awake. During deep sleep, the body releases growth hormones that promote the development of bones, muscles, and tissues. Sleep is essential for babies to rebuild their strength after periods of wakefulness.
- Energy Conservation: Babies grow fast in the first few months of life. Sleep helps them conserve energy for growth, digestion, and physical development. Their tiny bodies work hard to build muscle and develop motor skills, all of which require power.
But if sleep is so important, why do newborns seem to sleep in such short stretches?
Newborn Sleep Cycles: Short and Sweet
One of the most important facts about newborn sleep is that it’s different from the sleep cycles of older children and adults. A newborn’s sleep cycle typically lasts 50-60 minutes, much shorter than the 90-minute sleep cycles of adults. Each of these short cycles consists of two main stages:
- REM Sleep: Newborns spend about 50% of their sleep in REM, a lighter, more active stage of sleep. You might notice your baby twitching, smiling, or making small movements during this phase. REM sleep is essential for brain development, particularly for memory and learning.
- Non-REM (NREM) Sleep: This is the deeper stage of sleep where the body focuses on growth and repair. It releases growth hormones and restores energy. However, newborns spend less time in this deep sleep phase than older children and adults.
Because babies spend much time in light REM sleep, they are likely to wake up during short sleep cycles. This explains why newborns wake so frequently and need help falling back asleep. As your baby grows, their sleep cycles lengthen, and they’ll spend more time in the deeper stages of sleep.
Day and Night Confusion: Why Newborns Don’t Follow Your Schedule
One of the most common concerns of parents is why their baby seems to sleep all day but stays awake at night. This phenomenon is known as day-night confusion, and it’s completely normal in newborns.
Why Newborns Don’t Have Circadian Rhythm
In the womb, babies don’t experience the same day-night cycles as we do, and after birth, it takes time for their bodies to adjust to the rhythm of the outside world. Newborns sleep when tired, regardless of day or night. They don’t yet understand the concept of nighttime sleep versus daytime naps. When babies are born, they haven’t yet developed a circadian rhythm, the body’s natural 24-hour clock that regulates sleep and wake cycles.
How to Help Your Baby Develop a Day-Night Rhythm
While your newborn’s circadian rhythm won’t fully develop until they’re around 3-4 months old, there are gentle ways you can help them begin to differentiate between day and night. Here are some tips to encourage this development:
- Expose Your Baby to Natural Light: During the day, especially in the morning, take your baby outside or into rooms with plenty of natural sunlight. This exposure to light helps their bodies recognize that daytime is for being awake.
- Create a Calm Nighttime Environment: At night, keep the room dark, quiet, and calm. Use dim lighting during feedings or diaper changes, and avoid stimulating your baby with loud noises or bright lights.
- Start a Bedtime Routine: While your newborn may not fully understand a routine, establishing consistent nighttime habits signals your baby that it’s time for sleep. This could include a warm bath, a gentle lullaby, or dimming the lights.
As your baby’s internal clock develops, you’ll notice longer stretches of sleep during the night and more wakefulness during the day. But don’t be surprised if this process takes time—every baby is different, and some may take longer to adjust.
The Role of Sleep Stages in Newborn Development
When we think about sleep, we imagine a time of complete rest. However, sleep is incredibly active for newborns, particularly during REM sleep. This type of sleep takes about half of a newborn’s total sleep, the period in which the brain processes information and consolidates memories.
This active stage of sleep is essential for their cognitive development and emotional regulation. As your baby grows, they’ll spend less time in REM sleep and more time in deeper stages of sleep, similar to the way adults sleep. But in those early months, REM sleep dominates and plays a crucial role in shaping your baby’s brain.
A newborn’s sleep stages are very different from an adult’s. As mentioned earlier, babies go through shorter sleep cycles and spend more time in REM sleep. As they grow, their sleep stages begin to resemble adult sleep patterns. Here’s a breakdown of the different sleep stages:
- Stage 1: A light sleep where your baby can be easily woken. You may notice their eyes fluttering or twitching. It’s common for newborns to fall into this stage quickly.
- Stage 2: A slightly deeper sleep where their body temperature drops and their heartbeat slows.
- Stages 3 and 4: These are considered deep sleep (NREM), and it’s much harder to wake them up during this phase. This is where the body does most of its repair work.
What About Sleep Regressions?
Sleep regressions can sometimes frustrate parents who feel they’ve just gotten their baby into a regular sleep routine. Suddenly, your baby starts waking up more frequently, struggling to fall asleep, or becoming fussy at night. These are common during periods of rapid development. When your baby is learning new skills, such as rolling over, sitting up, or crawling, their brain is working overtime, which disrupts their sleep. The common times for sleep regressions are:
- 4 months: The first major sleep regression parents notice. Your baby’s sleep cycles shift, and they wake up more frequently at night.
- 8 to 10 months: Your baby is mastering physical milestones, such as sitting up or pulling to stand, which interfere with their ability to settle down for sleep.
- 12 months: Around their first birthday, some babies experience a regression as they begin to walk and explore their environment more independently.
Sleep regressions are a normal part of development and usually last a few weeks. While it is challenging, especially if you’ve just started enjoying longer stretches of sleep, know that these regressions are temporary.
How to Handle Sleep Regressions
While sleep regressions can be challenging, they are temporary. Here are some strategies to help you and your baby get through these phases:
- Stick to a routine: This is the best way to handle sleep regression. Keep a consistent bedtime routine to help your baby feel secure and signal that it’s time for sleep, even during a regression.
- Provide comfort, but avoid creating new sleep habits: Naturally, you want to comfort when your baby wakes more often, but be careful not to introduce new sleep associations that you’ll have to break later (like rocking them to sleep every time they wake).
- Be patient. Adjust your expectations. Sleep regressions are a sign that your baby is growing and developing, which is good! While it’s frustrating at the moment, these phases don’t last forever. Your baby’s sleep will go through many stages in the first year and it’s normal for their sleep patterns to shift as they grow.
Tips for Helping Your Newborn Sleep Better
Newborns have unique sleep needs, and while you can’t force them to sleep longer or stick to a schedule, some strategies help encourage better sleep.
1. Swaddle for Comfort and Security
Swaddling helps your baby feel safe and secure by mimicking the snug feeling of being in the womb. It also prevents their startle reflex (when they suddenly jerk their arms or legs), which wakes them up during light sleep. Ensure correct swaddling to keep your baby safe. Stop swaddling once your baby shows signs of rolling over, as this increases the risk of suffocation.
2. Feed on Demand
Newborns have tiny stomachs and need to eat frequently. They’ll wake up because they’re hungry, so feeding on demand ensures enough calories to stay content and sleep well. Nighttime feedings are normal and necessary in the first few months.
3. White Noise Can Be Your Friend
The womb is noisy, and some newborns find the sudden quiet of the outside world unsettling. Use white noise or soft sounds in the background to soothe your baby and block out household noises that might wake them.
4. Create a Safe Sleep Environment
Safety is always a priority in newborn sleep. Follow these safe sleep guidelines to reduce the risk of Sudden Infant Death Syndrome (SIDS):
- Always place your baby on their back to sleep.
- Use a firm mattress with a fitted sheet.
- Keep the sleeping area free of loose blankets, pillows, or stuffed animals.
For more advice on safe newborn sleep, check out this article for a related topic: How Bassinets Help Reduce SIDS Risk: The Science Behind Safe Sleep for Babies
5. Be Patient and Flexible with Yourself and Your Baby
Parenting is challenging, especially in newborn sleep. There’s no “right” way for babies to sleep. Every baby is different. Be patient with yourself and your baby as you navigate this new journey together.
6. Understand That Night Wakings Are Normal
It’s normal for newborns to wake up frequently, especially in the first few months. Their tiny stomachs can only hold so much milk at once, so they’ll need regular feedings throughout the night.
Signs of Newborn Sleep Issues
While frequent waking is normal, some signs may indicate a problem with your newborn sleep. These include:
- Chronic snoring or labored breathing: If your baby has difficulty breathing while sleeping or snores frequently, this could be a sign of a newborn sleep disorder, such as sleep apnea.
- Extreme fussiness or discomfort: If your baby seems uncomfortable or has difficulty settling down despite your efforts, it may be worth discussing with your pediatrician to rule out any underlying issues with newborn sleep, such as reflux or colic.
If you have concerns about your newborn sleep, book an appointment with your pediatrician as soon as possible. Your child’s pediatrician can offer guidance and expert advice on newborn sleep. Importantly, they can determine if any underlying issues need to be addressed.
Embrace the Science of Newborn Sleep
Newborn sleep is complex, and it can be hard to manage your baby’s needs while caring for yourself. However, understanding the science behind newborn sleep cycles and development helps you feel more confident in your approach. You can gently guide them toward healthier newborn sleep patterns over time by creating a calming sleep environment, following safe sleep practices, and adjusting your expectations.
For more tips on navigating the first year with your baby, look at these posts on common concerns during a baby’s first year.
- 10 Ways to Manage Night Wakings in Babies: A Comprehensive Guide
- 12 Tips for Establishing Healthy Sleep Patterns for Your Baby
With patience and time, you and your baby will find your rhythm.
