Safe infant sleep and breastfeeding are partners

Safe infant sleep and breastfeeding are partners

Infant sleep is misunderstood by most Americans. For example, like all social mammals, humans evolved to sleep with others. Most of humanity today, and throughout our six million year history, sleeps with others throughout life, including infancy. During early childhood, it accompanies prolonged breastfeeding on demand.

However, breastfeeding and infant sleep have for some time been considered separate elements in western and westernized countries. After the switch to artificial infant foods in the 20th century, more and more mothers are now turning to breastfeeding. Yet there are many misunderstandings between parents and their medical advisors. The American Academy of Pediatrics only in 2016 started advocating room sharing.

A recent article by three anthropologists reviews what is known about infant sleep and breastfeeding (Ball, Tomori & McKenna, 2019).

What do mother-baby experiments tell us about sleep?

  • Research shows that sleeping together with infants facilitates breastfeeding, the species-normal way of feeding young infants.
  • With solitary infant sleep, infants often sleep more soundly than when they sleep together. This can be dangerous for a young baby, who is otherwise a light sleeper, waking up frequently to nurse. It takes young infants months to learn to breathe and self-regulate outside the womb, and they can succumb to sleep apnea without their mothers present (McKenna, 2020).
  • Around three months of age, infants experience dramatic changes in respiratory control that make them vulnerable to unpredictable respiratory arrest (Mosko, Richard, & McKenna, 1997a). Maternal presence is linked to the stimulation necessary to restore breathing.
  • Mother and child co-regulate each other during co-sleep. Feeding frequency at night (as well as during the day) increases milk production.
  • Nighttime breast milk, which contains melatonin, facilitates the development of the infant’s circadian rhythm during the first months of life, before the infant is able to produce its own melatonin.
  • Difficult births, such as those requiring caesarean sections, create difficulties in that the investment in breastfeeding is diminished.
  • Birth interventions pose challenges to breastfeeding even when mother and baby are sleeping nearby.
  • Infants who sleep alone sleep less overall.

Cultural differences

Adults often believe they sleep through the night, as do infants. But these two ideas are recent cultural notions. Research in non-electrified communities indicates that there are two distinct sleep periods, each of about four hours. People wake up periodically throughout the night, and adult sleep doesn’t sync up.

LaBale et al. (2019) examines the history of “sleep problems” in Western societies. These emerged from industrialization, capitalism, the biomedicalization of sleep (i.e. pharmaceuticals), and the valuing of infant solitary sleep for ‘safety’. The use of sleep training to separate infant sleep by middle-class Euro-Americans is a recent cultural construct representing a tiny minority of the world’s population.

The sleep practices of various cultures have been well studied. Most mothers from non-industrialized cultures do not worry about infant sleep. The colonization of Western values ​​often fails in indigenous societies that have a long-standing understanding of infant security through closeness to the mother. The immigration of traditional Aboriginal families into a culture that provides guidelines for separate infant sleeping for the prevention of Sudden Infant Death Syndrome (SIDS) makes no sense to these families because they had never heard of the SIDS nor had ever experienced it. Instead, they viewed closeness to infants as a priority. Even in Japanese traditions, co-sleeping is considered essential to child rearing as it provides security, facilitates care such as breastfeeding, and ensures the well-being of the child (Tahhan, 2013, 2014) .

“Sleep on the breast”

“Sleep” describes the combination of breastfeeding and co-sleeping in a safe way, which breastfeeding mothers are most likely to do. It is considered an evolutionary adaptation that does not disturb maternal sleep and facilitates infant health (Mckenna & Gettler, 2016). Interestingly, due to the cultural stigma of sleep due to a history of artificial feeding and cultural norms of solitary infant sleep over the past decades, today’s parents often have accidentally rediscover the convenience and ease of maternal sleep. But they tend to keep this a secret from their medical providers and even other family members.

Sudden Infant Death Syndrome (SIDS)

One of the perceived disadvantages of co-sleeping and bed sharing is the fear of SIDS. There is also a lot of misinformation here. Research consistently shows that breastfeeding lowers the risk of SIDS in relation to artificial feeding.

In place, other factors increase the risk SIDS and fatal accidents (Blair et al., 2020):

  • Never initiate breastfeeding
  • Baby sleeping next to an adult who is impaired by alcohol or drugs
  • Baby sleeping next to a smoking adult
  • Sharing a chair with a sleeping adult
  • Sharing a sofa with a sleeping adult (”sofa-sharing”)
  • Sleep on soft bedding
  • Being born preterm or low birth weight
  • Sleep in a supine position.


Ball et al. (2019) conclude that a change in policy recommendations is urgently needed:

“The mismatch between Western cultural sleep expectations and the biological constraints of human babies exacerbates inequities in infant development, undermines parental resilience and compromises family well-being.”

For more research and advice on safe, scientifically-guided co-sleeping and bedsharing, go to