Here's everything you need to know about newborns and sleep (or lack thereof!)
Newborns sleep in short bouts – typically ranging from 30 minutes to 4 hours. They sleep at seemingly random times throughout the day and night, because their circadian rhythms have yet to be established (more info below). Newborns awaken easily, because they spend a large portion of their sleep cycle in “active sleep”, which is a light sleep state characterized by fluttering eyelids; rapid, irregular breathing; occasional body movements and vocalizations. Newborns vary greatly in the total amount of time they spend sleeping. In the first few days, the average newborn sleeps between 16-18 hours a day. By four weeks, newborn sleep averages about 14 hours. But the range varies greatly and it doesn't necessarily mean that something is wrong if your babe is sleeping significantly more or less, in fact, some four week old babies sleep as little as 9 out of 24 hours, whereas others sleep for 19 hours a day.
The timing of adult sleep is governed by circadian rhythms, which are physiological changes that follow a 24-hour cycle and many of these changes are influenced by your exposure to light. Even if you are sleep-deprived, morning light exposure helps ensure that you will be more alert during the day than you are at night. As the day wears on and darkness falls, your body begins to produce less cortisol and more melatonin. When you expose yourself to bright, artificial lighting in the evening (particularly to lights that include the blue part of the spectrum) you disrupt these changes and may find it harder to fall asleep.
Unfortunately for sleepless parents, newborn sleep is not governed by strong circadian rhythms. During pregnancy, babies are tuned into their gestational parent’s physiological cues about day and night. Fetal heart and respiratory rates speed up when their gestational parent is active (which works by rocking them to sleep) and slow down when they are sleeping (aka party time!). Such changes may be influenced by maternal hormones, particularly melatonin (the sleep hormone) and cortisol (a hormone that helps regulate waking) which passes through the placenta and may direct the fetus’ internal clock.
But once babe is earthside, this intimate hormonal connection is broken, and newborns must rely on their own internal clocks - which are underdeveloped and are just learning how to regulate. Most infants take about 12 weeks to show day-night rhythms in the production of melatonin. Circadian changes in cortisol, may take even longer to emerge. And, overall, babies may take 3-5 months before they “settle” at night—meaning that they sleep for more than 5 hours at a stretch.
Further, life on the outside provides another major challenge that is directly related to sleep: getting fed. Newborn sleep patterns are shaped by the length of time it takes them to feed, digest, and become hungry again. For most newborns, this means feeding every few hours or so. Although sleep episodes are brief and spaced in seemingly unpredictable intervals around the clock, your baby is adapting to a new life with demands that are fundamentally different from what they were used to in the womb.
Newborn sleep cycles: Why newborns are light sleepers
When adults fall asleep, we pass through a series of sleep stages, including bouts of deep (“slow wave”) sleep, and finally REM sleep. REM is famous for its association with dreaming. But it’s also known for its distinctive pattern of brain activity, which resembles that of the busy, waking brain. Adults are much more likely to awaken during REM than they are during deep sleep.
At the end of a REM session, the sleep cycle is completed. Adults either wake up or begin another sleep cycle. A single sleep cycle lasts about 90-100 minutes.
Newborn sleep follows a different pattern. When a newborn first falls asleep, she enters immediately into “active sleep”. This rather restless sleep state is similar to REM sleep in adults. Just as adults are more likely to awaken during REM, newborns are more likely to awaken during active sleep.
Newborns may remain in this active sleep state for 25 minutes or more, after which they slip into a deeper sleep state known as “quiet sleep.” Compared to active sleep, quiet sleep is characterized by slower, more rhythmic breathing, little movement, and no eyelid fluttering.
Babies are less likely to awaken during quiet sleep, but this situation doesn’t last long. After about 50 minutes, the sleep cycle ends. Newborns then either awaken or begin another bout of active sleep.
So newborn sleep is different in several important ways. For one thing, newborns spend much more time in active sleep than adults spend in REM. Adults spend only 20% of their sleep time in REM, whereas newborns spend at least 50% of their sleep in active sleep. In fact, several studies suggest that, over the course of a 24-hour day, newborns spend a much greater proportion of time - as much as 75% - of their sleep time in the active sleep cycle.
Further, newborn sleep cycles are much shorter than are adult sleep cycles and instead of 90-100 minutes, the average newborn sleep cycles last only 50 minutes or so. As a result, newborns are vulnerable to awakening much more frequently.
It’s normal for adults and babies alike to experience frequent arousals during sleep, and most of these arousals do not result in our waking up “all the way”. A baby who seems to be waking up may, if left alone, go back to sleep very rapidly. Moreover, newborns probably benefit from being light sleepers, as having a low threshold of arousal may protect babies from SIDS and active sleep might be crucial for a newborn’s brain development.
By recognizing these states of sleep, you can help your baby sleep better by allowing them to move between the two states of sleep. Try not to disrupt your baby if they are in light sleep, see if they will fall back into their deeper sleep.
What are the signs of sleep readiness? Your baby may show signs of being ready for sleep when you see the following signs:
- Rubbing eyes
- Yawning
- Looking away
- Fussing
Sleep Disrupters
- Growth spurts – most infants, when going through a growth spurt (usually around the ages of 7-10 days, 2-3 weeks, 4-6 weeks, 3 months, and 4 months), will nurse or want a bottle more often, and may even sleep less throughout the day.But most babies will sleep noticeably more (overall) during these growth periods because of the intense need to conserve energy.
- Developmental spurts
- Illness
- Teething
- Stress
Does it have to be quiet for my baby to sleep?
Babies will habituate (to become accustomed to by repetition or prolonged exposure) to their surroundings. Babies will get used to noise and it was actually as loud as a vacuum cleaner inside the womb. You may want to keep the room with dim lights and soft voices during the night to help them distinguish between the day and night.
TIPS FOR PUTTING A SLEEPING BABY DOWN
- When transferring baby out of arms, make sure that they’re fully asleep (about 5-10 mins ish after they fall asleep), but don’t wait too long (25+mins) where if they wake up during the transfer, they’re already done napping.
- When putting baby down on their back, put them down at an angle - butt first, then slowly lower their upper body, and then head last, as putting baby straight down can make them feel like they’re free falling.
- Place baby down on their side and once you feel them settle, gently and slowly roll them onto their backs.
- Warm the sleep surface ahead of time with a hot water bottle or heating pad, as one of the big reasons babies wake upon transfer is the abrupt temperature change from your body to their bed. Be sure to remove before putting baby down.
- Place baby down slowly and let your hands feel them settle into the mattress. Heavy hands on the chest can facilitate this transition, and slowly remove one hand at a time when you know baby is asleep.
- To test if baby is truly out cold, gently their hand or arm and see if it’s heavy and limp. If so, this is a good time to try the transfer!