Parents are commonly concerned when their baby does not sleep through the night, especially if the largest stretch of sleep is not when they sleep. The results of this study give us a guide of appropriate developmental expectations for infant sleep, and help determine the optimal timing for prevention and intervention of sleep problems. From a developmental perspective it reflects an understanding of infant’s physiological capabilities in self-soothing and sustained sleep, showing the large variability of this from one baby to another.
This NZ based study enrolled 75 parents of healthy, developing infants and parents completed sleep diaries for 6 days each month for 12 months. Parents recorded the time and at what state the infant was placed into the cot and then the duration of time until the infant fell asleep. Parents also recorded the time and duration of each night-awakening and the time that their baby woke in the morning. Accuracy of parent reports were assessed by using videosomnography (diagnosis by behavioural observation).
The sleep of each infant was classified based on the three criteria below:
1) 2400hrs to 0500hrs
2) 8 hours of uninterrupted sleep
3) 2200hrs to 0600hrs
The findings of the study showed that self-regulated sleep (without behavioural intervention) became apparent most rapidly in the first four months, with 50 percent of infants meeting criterion 3) at 5 months. From 4-9mths age infant sleep length tended to plateau and began to lengthen again between 10 and 12months. However at 12 months age, 32 percent of infants still did not meet criterion 3) - many babies do not sleep through the night by one year of age but are still perfectly healthy and this is not necessarily problematic.
The authors of the study recommend that criterion 3) should be used to define ‘sleeping through the night’ for babies from the age of 4 months. The reason for this is because it is harmonious with family sleep patterns, and falls within typical sleep times of the parents. Additionally, it is recommended that prevention of sleep challenges should begin before 3 months, emphasising the importance of working with infant sleep biology to determine healthy sleep habits in the long-term.
Many families aim to put their baby to sleep at 7pm but why do we place this expectation on our baby? A later bedtime may be better suited for baby’s actual sleep patterns and may also be beneficial in synchronising their sleep with their parents. It is actually possible to aid in the prevention of sleep challenges by achieving a synchronised sustained period of sleep during the night after completing day to day activities and self-care tasks. For example moving bed time routines out to a later hour can not only help with preventing sleep challenges but perhaps even more importantly, reset parents’ expectations of their baby’s developmental capabilities.
One of the main limitations of this study was that there was no data provided on the method of infant feeding (i.e. breastfeeding or formula feeding) as this does seem to impact sleep duration and quality of sleep. Many parents believe that supplementing their babies with formula feeds will encourage earlier sleeping through the night. A separate study has found that although breastfed babies do wake more frequently in the night, they often get better quality sleep as they settle back to sleep more easily.
Additional research is now needed to establish the factors that precede and predict infant sleep problems.
For full aticle please see:
Sleeping Through the Night: The Consolidation of Self-regulated Sleep Across the First Year of Life
If we were to look at cultures purely in terms of their infant care practices, norms and values, which culture would you choose to be born in to? Think carefully, as this choice can make a huge impact on how you develop as a healthy, happy baby. Because the thing is, it does not matter which culture or country an infant is born into, its biological needs are the same – but does the culture a baby is born into meet these needs? Or does it promote crying, fussing, feeding and sleeping issues?
The western culture’s predominant norms and practices around infant care often stray very far from what a baby biologically requires. In fact, when describing how both historically and cross-culturally unusual our parent-infant sleep practises are, researches have come up with this acronym to describe the worst offenders - W.E.I.R.D (western, educated, industrialised, rich and democratic), (Heinrich et al., 2010).
The western way of child rearing is one of the biggest mismatches between culture and what a baby biologically expects.
Human babies are mammal babies, more specifically secondary precocial. This is because typical brain growth cannot be completed before birth. Human babies have 25% adult brain growth at birth, compared with 50% of other primates. Humans produce mainly single infants that have well developed internal and sensory organs (can see, hear and call) but our babies have poorly coordinated neuromuscular control, so cannot follow or even cling to their caregiver. Our milk is low in fat and high in sugar, so our infants need to be fed frequently.
Every primate baby is designed to be physically attached to someone who will feed, protect and care for them. They have been adapted over millions of years to expect nothing else and humans produce unusually helpless primate babies!
When you take this into consideration and then think to some of the predominant advice around caring for a new born e.g. teach them to self-settle independently, space their feeds, do not let babies fall asleep at the breast, put babies to bed awake, carry out feed/play/sleep cycles, leave babies to cry or leave them to cry but give them verbal ‘reassurance’, do not let your baby form ‘bad habits’, don’t let your baby sleep on you, enforcing feeding and sleeping schedules or routines and never co-sleeping (for families that have no risk factors and are doing it completely safely), you can start to see what I am talking about.
The dominant western approach to infant care has evolved far faster than baby’s biological needs ever could and this is why there is such a mismatch.
So where does this ‘expert’ advice that pervades western culture come from? During the 1920’s, doctors John B Watson and Frederick Truby King advocated the ‘scientific’ approach to infant care. The focus of their approach valued independence, self-control and self-reliance. It is this focus which you can still see today in many approaches to infant care – particularly in the management of crying, fussing, feeding and sleeping challenges.
It is this approach which encourages independence, self-control and self-reliance that research clearly shows has no beneficial outcomes for infants. In fact, some variations of this approach can at times result in negative outcomes.
So, what can you do to ensure that you are doing your best to meet your baby’s biological needs, to provide them with a loving environment that helps to achieve optimum development, bonding and attachment? Quite simply – physical contact and emotionally connecting with your baby – day and night. 24/7.
Physical contact does so many amazing things for parents and their babies. It reduces maternal anxiety and promotes involvement in their infant’s care, is great for breast feeding initiation and long-term breast feeding success, reduces stress, promotes oxytocin, beta endorphins, prolactin and sleep, conserves heat and energy, can reduce pain levels, premature babies experience less agitation and have more stable vital signs.
You only need to google ‘The still face experiment’ to see the stress inducing effect that a non-responsive caregiver has on a baby – even when in very close proximity.
Rest assured, there are no rules required to meet the biological needs for babies. As mothers, we can just remind ourselves that our babies can communicate to us what they need and through our own biological changes during pregnancy and childbirth, our brains are now primed to learn how to understand our baby’s ways of communicating - to build good two-way communication and trust.
Instead of a culture based on maintaining control and pushing independence, a culture of respect and kindness towards our babies and focusing on meeting their biological will ensure that over time the gap between what dominant western approaches to infant care advocate and what babies genuinely need will continue to narrow.
Prof. Helen Ball, Possums Conference, Brisbane 2017.
Pennie Brownlee. The only person who can do a Pikler is dead: Or why isn’t it a good idea to say ‘We do Pikler at our centre’. February 2015.
Heinrich, J., Heine, S., & Norenzayan, A. (2010). The weirdest people in the world? Behavioural and Brain Sciences, 33, 61-135.
Have you ever wondered why no matter how many babies you have you never quite feel complete and ponder over the possibility of another? This is an addiction to the feel good hormone, Oxytocin. This powerful hormone has the important job of reproductive success and species survival: nature’s way of patting you on the back and telling you “Good job. Have more babies.”
Making babies, having babies and feeding babies. Oxytocin is produced during sexual activity and orgasms, its analgesic properties are helpful in labour and birth, and its release is triggered in both mother and baby when a baby suckles at the breast.
Alternatively most of us know what it feels like to experience the ‘fight of flight response’ and it’s not what you would describe as desirable – a pounding, racing heartbeat, cool sweaty skin and hyperarousal. These symptoms present through a stress response which is activated by the sympathetic nervous system with intertwined hormones adrenaline noradrenaline, such as cortisol. These responses are very much tied in with labour which can be painful and stressful. Stress hormones during childbirth can either slow down or accelerate labour depending on the stage. Historically this response was important for survival: if you were giving birth in the wild and there was a threat to your survival (such as a sabre-toothed tiger suddenly appearing!), you would have an out pouring of stress hormones and blood would be shifted away from your placenta to your vital organs. As a result labour would stop so you could run away to safety where labour could resume. However, if you were in the final stages of labour when the tiger appeared, you could not run so it makes biological sense that these hormones at this latter stage would assist with giving birth quickly, so you could scoop up your baby and run to safety.
Oxytocin in this sense is just the opposite: activating the parasympathetic nervous system encouraging relaxation and growth, a feeling of calmness safety and security which promotes bonding and attachment. After having a baby you quickly forget about the associated pain and stress and immediately begin to bond with your baby; oxytocin’s side effects present as that lovely hot flush that new mothers get and baby is wide-eyed ready to bond. Activation of the reward, pleasure and motivation centres is happening during this time. No other mammals attend antenatal classes to be told how to care for their baby so there needs to be a hormonal system in place to kick in straight after births so that mother finds contact with her baby very rewarding. Mother Nature rewards us for the dedication to caring for your baby for maximal chance of mother and baby survival and species survival. It’s not hard to see why this hormonal system has been selected for during mammalian evolution.
Breastfeeding on demand is how you can keep your baby’s sympathetic nervous system dialled down and prevent activation of the fight or flight response. This is especially important during the first 4-6 months of a baby’s life during the phase of high neurological sensitivity. Oxytocin is working its magic - mother feels an overwhelming need to protect, provide and nurture her baby making her feel good and this motivates her to keep doing what she is doing. Baby feels safe and secure and remains calm when it has all its needs have been need met, including feeling satiated with a tummy full of creamy milk and sensory nourishment through physical contact. Babies that receive plenty of physical contact with their caregiver cry less and breastfeed for a longer duration.
Many parents have a specific time frame that they think their baby should be sleeping through the night by and can find it disheartening when they continue to wake during this period. Despite eating solids well and having plenty of protein they still wake up.
But they can’t be hungry so why?
It's important to understand that babies (not just new-borns) feed for reasons other than just to satisfy their hunger and met their growth demands. Often night wakings will be for the physical contact, feelings of security, pain reduction and the calming effects of oxytocin. When we as parents have set times in our mind that baby should be sleeping and not feeding, and we stop responding to our baby’s cues, and they can become stressed. This can lead to negative effects on development as well as prolonged and unpleasant night waking, which is what we want to avoid. This can be managed by being responsive to your baby’s needs. It may not be a consistent pattern but it won’t last forever either. We have all had days and nights that have been tough and it’s amazing to think that over time our minds seem to be very clever at washing away those unhelpful feelings associated with those distant memories.
Just one more baby… it can’t be that hard right?
-Adapted from a talk given by Dr. Sarah Buckley at the Possums conference, Brisbane 2017.
Amy and Elspeth