Newborn Day-Night Confusion: Why Days and Nights Get Mixed Up

What is day-night confusion in newborns?

Day-night confusion, which the American Academy of Pediatrics (AAP) calls day-night reversal, is when a newborn sleeps more during the day and stays awake more at night, because, as Cleveland Clinic explains, newborns have not yet developed the internal 24-hour rhythm that tells them when to be awake and when to sleep.

The AAP says newborns are known on occasion to mix up their days and nights, sleeping more by day while demanding to be fed, changed and entertained throughout the night.

Ireland's Health Service Executive (HSE) says newborns do not know the difference between day and night, and that their sleep is more likely affected by hunger. The HSE adds that a baby's appetite often influences their body clock.

The ages below are approximate, and each source words its finding differently.

Age	What the source describes	Source
Newborn	Does not know the difference between day and night; sleep more likely affected by hunger	HSE
As early as 8 weeks	Cortisol rhythm responsible for wakefulness develops	European Journal of Pediatrics review (2024)
About 8 to 12 weeks	Melatonin starts following a daily rhythm in full-term babies (about 9 weeks for the sleep-onset rhythm), even later in preterm babies	European Journal of Pediatrics review (2024)
A few months	Day-to-night pattern of waking and sleeping often takes this long to settle	HSE
Several months	Day-night pattern of wake and sleep often takes this long to become established	Basis (Durham University)

How long does newborn day-night confusion last?

Day-night confusion has no fixed end date in the guidance: the AAP says day-night reversal will pass, the HSE says it often takes a few months for a baby's day-to-night pattern of waking and sleeping to settle, and Basis, the Baby Sleep Info Source, says it often takes several months for that pattern to become established.

A 2024 scoping review in the European Journal of Pediatrics says melatonin starts following a daily rhythm at around 8 to 12 weeks in full-term babies, and even later in preterm babies.

Basis gives separate timings for longer stretches at night. It says that by 3 months some babies, but not all, begin settling, which it defines as sleeping through a nighttime feed for a stretch of up to 5 hours, and that by 5 months half of babies may have slept for an 8-hour stretch on some nights.

Basis says popular beliefs about when babies should sleep through the night come from 1950s and 60s studies of formula-fed babies, and that it is normal for babies, especially breastfed babies, to wake and feed at night throughout at least the first year.

How do you fix day-night confusion in a newborn?

To help a newborn tell day from night, the AAP and the NHS both advise keeping days light and ordinary and nights dark and quiet, with nighttime contact kept to what your baby needs. The AAP says there is really no quick fix, and suggests setting up an atmosphere that clearly differentiates night from day during your first few weeks at home.

During the day

• The NHS suggests opening the curtains, playing games and not worrying too much about everyday noises while your baby sleeps.
• The AAP says not to worry if your baby falls asleep in active areas of the house, such as rooms with light or music on, and not to be afraid to run an occasional daytime errand.
• Cleveland Clinic suggests keeping your baby in bright or sunny spaces during the day to help them develop an internal clock.

At night

• The AAP suggests limiting nighttime interactions to feeding, burping, changing and gentle soothing when necessary, in a dark room with a soft voice.
• The NHS suggests keeping the lights low, not talking much and keeping your voice quiet, not playing, changing your baby only if they need it, and putting them down as soon as they have been fed and changed.

For where your baby should sleep after a night feed, see safe sleep practices for infants.

The NHS says a simple, soothing bedtime routine may help your baby settle, and that your baby will gradually learn that nighttime is for sleeping.

The 2024 scoping review found that lighting on a day-night cycle improved nighttime sleep and daytime wakefulness, though its experimental studies focused on preterm babies in hospital. One home study it included, of 43 babies aged 3 to 5 months, so older than newborns, found that light exposure during the day promoted efficient sleep at night and daytime waking.

Should you wake a sleeping baby during the day?

Keeping a newborn awake during the day will not help them sleep better at night, according to the HSE, and the AAP's advice on waking a sleeping newborn is about feeds. The HSE says an overtired baby finds it much harder to get to sleep, and Cleveland Clinic says an overtired baby has a hard time falling and staying asleep.

The AAP's waking advice differs by feeding method:

• Breastfeeding: the AAP says that if your newborn sleeps longer than 4 hours a night, wake them up and encourage them to nurse.
• Formula feeding: the AAP says that if your baby sleeps longer than 4 to 5 hours during the first few weeks after birth and starts missing feedings, wake them up and offer a bottle.

For how long babies usually stay awake between sleeps, see wake windows by age.

What does newborn sleep look like over 24 hours?

Newborn sleep comes in short stretches across the day and night: the HSE says newborns may sleep for 1 to 3 hours between feeds, and Cleveland Clinic says sleep in the first two months comes in many short bursts of about 30 minutes to three hours at a time.

The HSE says babies need about 9 to 18 hours of sleep until age 3 months, and sleep an average of about 14 hours. The NHS says most newborns are asleep more than they are awake, and that their total daily sleep varies but can be around 18 hours. Basis says newborns may sleep for 18 or so hours a day, but often for only 2 to 3 hours at a time.

Basis says newborns have very small stomachs and wake about every 2 hours to feed, with some waking more often and some going longer. For how sleep changes through the first year, see how much sleep a baby needs by age.

When should you call your pediatrician about newborn sleep?

Talk to your pediatrician or family doctor if your newborn is hard to wake, seems uninterested in feeding, or is very sleepy with yellowing skin, if a breastfed newborn often misses feeds or sleeps through the night, and whenever you are worried about how much your baby sleeps.

• Your baby has a difficult time waking up, seems uninterested in feeding, or seems extremely fussy and soothing isn't working. Cleveland Clinic lists all three as reasons to talk to your pediatrician.
• Your newborn has jaundice (yellowing of the skin) and is very sleepy. The HSE advises talking to a family doctor or public health nurse.
• You breastfeed and your newborn frequently misses nursing sessions or sleeps through the night. The AAP lists this as a warning sign of breastfeeding problems and says to contact your baby's pediatrician.
• You are worried your baby is not getting the right amount of sleep. The HSE advises talking to a family doctor or public health nurse.