Typical sleep

How long should my baby sleep at night?

Sleep time changes as babies grow. Newborns tend to wake up to breastfeed every two to three hours. Between one and six months, most babies breastfeed one to three times a night. They often have a fussy period in the evening when they feed frequently, taking in a lot of milk and tire themselves out being cranky. As a result, they may sleep for five hours. Between 5 and 12 months, most babies still wake up at least once a night, whether they are breastfed or fed infant formula. The evening fussy period stops between four and six months, so without the extra milk, some babies may start to wake more. This is normal but can be frustrating for families. After one year, babies wake less and less during the night as their sleep patterns become more like an adult’s.

A) Describing sleep

Infant sleep is a complex and controversial topic. Babies have unique sleep patterns that vary with:

  • Age.
  • Feeding type.
  • Personalities.
  • Environment.

Expectations of how a baby should sleep vary with:

Parental sleep is the most affected in the first three months after the birth of the child (Richter 2019). However mothers and fathers of both breast and infant formula-fed babies may take up to six years after the birth of their first child to be satisfied with their sleep (Richter 2019). 

B) Sleep changes with age

Sleep patterns change as the baby grows.

1) Birth to six months

Nighttime feeds are normal for babies up to five months of age and beyond. Newborns tend to wake up to breastfeed every two to three hours through the night.

Many babies have a fussy period in the evening followed by a five-hour sleep (the evening fussies). These can start as early as the second evening after birth or as late as three weeks after birth.

During the evening fussies, babies feed frequently and take in a lot of milk to prepare for a longer sleep. They also need more sleep after being cranky for a few hours. Without the fussies, they generally wake to feed every two to three hours through the night.

Between the ages of 1 and 6 months, 64% of babies breastfeed one to three times a night and take in about 20% of their daily milk intake during this time (Kent 2006).

2) Six to 12 months

a) Night-time waking is normal

At this age, many parents expect babies to sleep through the night. However, most still wake and need to feed.

One study (Brown 2015) looked at 715 mothers and their babies between 6 and 12 months of age. Some were breastfed and some were fed infant formula. The study found that:

  • There was no difference in how often breast- and infant formula-fed babies woke up.
  • 78% of all babies at this age regularly woke at least once during the night.
  • 61% of all babies who woke at night had one or more feedings.
  • Babies who received more milk or solid foods during the day were less likely to feed at night but not less likely to wake. This suggests that increasing the baby’s caloric intake during the day may reduce the need to feed the baby at night but will not reduce the need to attend to the baby.
  • The incidence of night awakenings and night feeds decreased with age.

b) Infant formula use and starting solid foods do not have a significant effect on night waking

One study (Pennestri 2018a) showed that the overall amount of sleep that babies get at six months was the same for breastfed and infant formula-fed babies and that the sleep patterns of both groups were the same by two years of age.

One study (Perkin 2018) showed that starting solid foods at three months instead of six, had only a minimal effect on decreasing night wakings (from 2.01 to 1.74) and on increasing the amount of sleep (16 minutes longer) at six months of age.

Even at 12 months, one-third of both breast- and infant formula-fed infants will wake before 6 hours (Pennestri 2018a). 

c) Increased waking up after six months of age

Some babies wake up more in the second six months of life than during the first six. The evening fussies, when babies take in a lot of milk and tire themselves out, stop when the baby is between four and six months of age. Without the evening fussies, the five-hour sleep can disappear. This pattern can be frustrating but is normal.

The more frequent waking in the second six months is sometimes called sleep regression, a word that means returning to a former or less developed state. It is not an ideal label as these babies are developing normally.

A baby’s sleep pattern may not be consistent, with nightly shifts between shorter and longer sleeps.

3) After one year

Many babies generally don’t sleep for more than five hours in a row during the first year. After that, their sleep pattern starts to mirror the adult pattern. They wake up less and less during the night. 

Waking up with a baby can be tiring, but it is normal for babies to wake in the night and they eventually grow out of it. Human babies share this behaviour with other primates (Nishida 2012).

One study showed that babies who were breastfed during the first six months were less likely to feed after midnight at one year of age (Wee 2017). Another showed that babies who were breastfed were better sleepers at three to five years of age (Herring 2020).

D) The changes in breast milk between day and night 

Breast milk can be called timed nutrition (chrononutrition) as the levels of some breast milk components change during the day and night. These variations may be providing nutrients when they are most needed by the baby, teaching and supporting the baby’s internal clock, and synchronizing the mother’s and baby’s bodies.

For example, breastfeeding mothers and babies have similar patterns of rises and falls in their blood levels of a particular hormone (cortisol) during the first year of life (Jonas 2018). This relationship is reduced in infant formula-feeding pairs.

E) The perception of sleep problems

It is normal for babies to wake at night to feed and sleeping for more than five hours at one time can affect breastfeeding and slow the baby’s growth. However night wakings are perceived differently between families and around the world and responses vary accordingly.

One study (Mindell 2010) showed that the number of parents who thought their children had a sleep problem ranged from 11% in Thailand to 76% in China. A group of American mothers were surprised by the amount of care babies needed at night (Kennedy 2007).

Even bed-times vary. One study (Mindell 2010) looked at sleep patterns in 16 countries and found average bedtimes for babies and young children ranged from 19:30 (7:30 p.m.) in New Zealand to 22:15 (10:15 p.m.) in Hong Kong . Bed-sharing also varies widely between countries.

F) The pressure on parents

There is a lot of controversy over the issue of babies waking at night. Some parents are told that their babies need uninterrupted sleep to grow and develop properly but the existing research, showing the benefits of adequate amounts of sleep, is mostly on the total amount of sleep and not whether it is interrupted or not (Pennestri 2018b).

Even though night waking is normal, mothers may feel tense or depressed when their babies fail to sleep without waking (Germo 2009). Families may even be told that their baby is “spoiled” or “high needs” because the baby wakes during the night. 

References

Brown A, Harries V. Infant sleep and night feeding patterns during later infancy: association with breastfeeding frequency, daytime complementary food intake, and infant weight. Breastfeeding Medicine. June 2015, 10(5): 246-252
 
Germo GR, Goldberg WA, Keller MA. Learning to sleep through the night: Solution or strain for mothers and young children? Infant Ment Health J. 2009 May;30(3):223-244
 
Hahn-Holbrook J, Saxbe D, Bixby C, et al. Human milk as "chrononutrition": implications for child health and development. Pediatr Res. 2019 Jun;85(7):936-942

Herring A, Kolbo J, Choi H, et al. Breastfeeding History, Preschool Children's Sleep, and Obesity. Compr Child Adolesc Nurs. 2020 Aug 31:1-11

Jonas W, Bisceglia R, Meaney MJ, et al. The role of breastfeeding in the association between maternal and infant cortisol attunement in the first postpartum year. Acta Paediatr. 2018 Jul;107(7):1205-1217
 
Kennedy HP, Gardiner A, Gay C, et al. Negotiating sleep: a qualitative study of new mothers. J Perinat Neonatal Nurs. 2007 Apr-Jun;21(2):114-22
 
Kent JC, Mitoulas LR, Cregan MD, et al. Volume and frequency of breastfeedings and fat content of breast milk throughout the day. Pediatrics. 2006 Mar;117(3):e387-95
 
Mindell JA, Sadeh A, Wiegand B, et al. Cross-cultural differences in infant and toddler sleep. Sleep Med. 2010 Mar;11(3):274-80
 
Nishida T. Chimpanzees of the Lakeshore: Natural History and Culture at Mahale [Internet]. Cambridge: Cambridge University Press; 2012
 
Pennestri MH, Laganiere C, Pokhvisneva I, et al. (Pennestri 2018a). 0253 Sleep Patterns As A function of Breastfeeding: From Infancy to Childhood. Sleep 2018; Suppl 41(suppl_1):A98-A98
 
Pennestri MH, Laganière C, Bouvette-Turcot AA, et al. (Pennestri 2018b). Uninterrupted Infant Sleep, Development, and Maternal Mood. Pediatrics. 2018 Nov 12. pii: e20174330
 
Perkin MR, Bahnson HT, Logan K, et al. Association of Early Introduction of Solids With Infant Sleep: A Secondary Analysis of a Randomized Clinical Trial. JAMA Pediatr. 2018 Aug 6;172(8):e180739
 
Richter D, Krämer MD, Tang NKY, et al. Long-term effects of pregnancy and childbirth on sleep satisfaction and duration of first-time and experienced mothers and fathers. Sleep. 2019 Apr 1;42(4). pii: zsz015
 
Wee PH, Loy SL, Toh JY, et al. Circadian feeding patterns of 12-month-old infants. Br J Nutr. 2017 Jun;117(12):1702-1710