Historically, women all over the world have effectively combined co-sleeping and breastfeeding for thousands of years in order to meet the psychological, physical and social needs of their infant. Breastfeeding infants feed regularly throughout the day and night time during the early months of life. Mothers who are breastfeeding their infants need to be in close proximity to their infant in order to read their infants cues and meet their needs for nutrition, comfort and safety.

Breastfeeding and Co-sleeping

According to McKenna and McDade, “mother-infant co-sleeping represents the most biologically appropriate sleeping arrangement for humans and is both ancient and ubiquitous simply because breastfeeding is not possible, nor as easily managed without it.”(1). “Human infants are born more helpless than any other animal species” (2) and with only 25% of their adult brain size in comparison to other mammals who are born with their brain at 60-90% of its adult size. Human infants therefore belong in a biologically dependent state for a longer period of time. (2) A study exploring the relationship between breastfeeding behaviour and routine sleep arrangements of mother-infant breastfeeding dyads over three consecutive nights concluded that routine bed sharing was “…associated with significantly greater number of feeds per night compared to mother-infant dyads who routinely sleep separate from one another in different rooms”(3).

Effects of Co-Sleeping on Breastfeeding

The effects of co-sleeping for the breastfeeding infant and their mother include and are not limited to: greater milk supply due to the baby feeding more regularly throughout the night which assists with milk production; more frequent breastfeeding which means that the infant cries less, is able to conserve their energy and spends more time in calm wakefulness; longer breastfeeding sessions and breastfeeding duration. The infant who co-sleeps experiences increased safety as they are constantly monitored throughout the night; they have lower stress levels as they do not have to cry long enough to awaken their parents who may be sleeping rooms away from where they are and ”they achieve longer and better rest periods.”(2)

Babies who co-sleep have an increased sensitivity to mother’s communication (smells, movements and touches- and visa versa) and have better temperature regulation because their mother can sense and respond to their needs for warmth and cool. Mothers may also experience enhanced attachment and parental fulfilment especially if they are working and are away from their infant during the day. (2) Finally and of great significance, “Not breastfeeding is now known to be an independent risk factor for Sudden Infant Death Syndrome(SIDS) as is an infant sleeping alone in a room by itself” (3 & 4). Also, “bed-sharing promotes infant arousal which may be protective against SIDS”(5)

What is Co-Sleeping

Co-sleeping is defined as “…a practice in which babies and young children sleep close to one or both parents, as opposed to in a separate room.”(6) Bed sharing is a practice by which the infant shares the same sleep surface as one or both parents/caregiver. McKenna and colleagues provide a more descriptive definition of mother-infant co-sleeping to be “…any situation in which a committed mother sleeps within sensory range of an infant (on the same or different surface) permitting mutual monitoring, sensory access and physiological regulation, including (but not limited to) the delivery and ingestion of breast milk.”(3) It can be said then that co-sleeping refers to room sharing and/ or bed sharing and many mother- infant dyads may alternate their sleep environment between room and bed sharing on more than one occasion throughout any one night. Infant sleeping practices vary enormously across many cultures and nations and in many of them co-sleeping is the norm until children are weaned or sometimes long after weaning.

Examples of global co-sleeping practices are that in Japan parents often sleep in close proximity with their children until they are teenagers. This sleeping arrangement is described by Japanese people as; the mother is a river bank and the father is another and their child sleeping between them is the river. (2) Similarly a study in 2006 of Indian children aged 3 to 10 reported that 93% of them were ‘bed sharing’ with their parents. In Latin America, the Philippines and Vietnam, some parents sleep in a hammock with their baby next to the bed, while others may place their baby in a wicker basket between the parents in the adult bed. (2) Many cultures that routinely practice co-sleeping have very “rare instances of Sudden Infant Death Syndrome (SIDS). (1, 2) Maternal smoking rates in these cultures are also low and “SIDS is either considered rare or is unheard of”. (2) It is well known that a combination of bed-sharing and smoking by one or both parents increases the infant’s risk of SIDS. (5)

How Many Parent’s Co-Sleep

Co-sleeping is not an unusual practice for families living in the USA and Australia. In the USA, 44% of infants between 2-9 months of age are co-sleeping in an adult bed at any given time (2). Consistent with rates in the USA, a recent Australian unpublished study of 1000 mothers of children aged up to two years of age showed that 41% of the mothers surveyed “allowed their baby to sleep in their bed with them”(7). Parents/caregivers sharing an adult bed with their infant is considered a risk factor for sudden infant death syndrome and in certain situations is not recommended by health and government authorities. (8) Most recent figures on sudden and unexplained death of an infant (SUDI) (including SIDS deaths) equated to 0.5 per 1000 births in Australia in 2010(34 of these deaths occurring in NSW).(10)

Where all known risk fa