Life in the first 6 months of being a parent! Feeding methods and parental factors.

In this series of mini blogs we look at life in the first 6 months of your baby’s life. Week 2 discusses how feeding methods and parental factors affect baby sleep.

Does feeding method make a difference to baby sleep?

There is evidence to show that exclusively breastfeeding mothers get the most sleep in these early months and that mixed feeding mothers get the least! This is not meant to discourage a mother from mixed feeding her baby, as any amount of breastmilk is highly beneficial. It is merely meant to demonstrate what effect parental behaviour can have on baby sleep. Let me elaborate!

Breastfeeding – not compatible with sleep?

Breastfeeding mothers who co-sleep with their babies – whether this is in the family bed or in an adjacent baby sleep space get the most sleep of all mothers despite their babies waking more frequently. This is because the baby is in close proximity and because breastfeeding induces melatonin in the mother and passes to the baby. Therefore, despite more waking, mum and baby settle quickly back to sleep, and often mum is unaware of how many times her baby may have fed in the night.  Why is baby waking more frequently? Most likely due to the need for a breastfeed to induce sleep – i.e. baby associates breastfeeding with how they get to sleep so every time they stir and move through a sleep cycle, they need a quick feed to resettle them. This is only a problem if mum deems it so and has been the biological norm throughout human history.

So, what is a bottle-feeding mum doing differently?

Firstly, bottle feeding babies are not as safe in the parental bed as a breastfeeding baby – this is due to baby being in a deeper sleep and baby not associating the breast with night-time comfort. This means baby is more likely to be closer to mum’s face rather and therefore nearer pillows. Breastfeeding mums also assume a curved side lying sleep position automatically, which bottle-feeding mummies do not seem to do.

Secondly, getting up to prepare a bottle (regardless of prep method or whether it is expressed breast milk) is generally much more disruptive to maternal (or paternal!) sleep than offering a quick breastfeed. Therefore, bottle feeding mums will often offer an alternative source of comfort and settling. This reduces baby’s dependence on one method of settling only, in addition it takes time to get up and prepare a bottle thus baby is naturally having to wait before comfort and/or milk arrives.

Whether this is beneficial or not depends on your point of view – sometimes baby will be very cross about the wait and therefore take into more air, feed more vigorously and take longer to settle after a feed – obviously not ideal at 3am! Sometimes however, baby will stir, shuffle about, whinge a little and then drift off back to sleep. If mummy has to get up to make a feed, she is likely to wait to see if baby is really going to shout for this feed before leaving the warmth of her bed – therefore she gives her baby a chance to resettle themselves, and they start to learn this skill.

Breastfeeding mummies know that if they offer the breast quickly at first sign of baby stirring then baby will drift off to sleep after that feed without a fuss. There really is no right or wrong between these 2 scenarios.

So how does the poor mixed feeding mummy end up with less sleep?

Interesting Kendall-Tackett et al (2011) report no statistical difference in maternal physical health and self-reported energy levels between mixed and fully formula feeding mums. Although these mums did report increased tiredness over formula feeding mums. In a large Chinese study, however, it appeared that partially breastfed infants woke more frequently than exclusive breastfed babies and formula fed infants (Huang et al, 2016). Increased night waking among partially breast-fed infants in the above study may be explained by more frequent infant feeding among partially breast-fed infants compared to exclusively formula-fed infants. It may be that the exclusively breastfeeding mums did not realise how often their babies were feeding?

So, what about regressions and leaps?

Are these a ‘thing’? We have seen in part 1 that a baby’s sleep changes dramatically at around 4-5 months – is this really a regression or a huge development?

Leaps is a term coined by Frans Plooij and his wife in their popular ‘Wonder weeks’ book and app – they describe weeks during a baby’s first 20 months which are particularly disruptive to sleep. The research behind this book has not been able to be replicated and it was based on a very small sample size. Regardless of the debate of the validity of the research, there is no doubt that as a baby makes physical and cognitive developments, their new perspective of their world will understandably lead to disruptions in sleep.

What parental factors do we need to think about?

Family dynamics – some of the factors which influence how a family feels about their sleep situation are listed below. Often a parent feels that improving a child’s sleep will improve their sleep and therefore their daytime functioning. While this is true in some cases, often there are lots of variables in each family’s situation.

Factors such as; parenting without support, the influence of surrounding community or culture and whether grandparents/partner and/or friends are supportive, can have a huge influence on how a parent feels about sleep.

Herman et al (2012) found less parenting stress was related to more positive parenting perceptions. As parental stress will affect child behaviour and stress levels (Barsade, 2002) supporting a parent with a holistic approach may improve family sleep by itself.

Emotional health of the parents is not the only factor in influencing family sleep, physical health made worse by lack of sleep is often an issue (Walker, 2017). This also makes it very hard for the parent to have the resilience or ability to make changes. Financial and work situation is often a motivator for parents to make changes as they are concerned about how they will manage work on a lack of sleep. This might result in a situation where the child’s sleep is developmentally normal, but the parent cannot manage their daily tasks on top of poor sleep (Meltzer and Mindell, 2007).

Sometimes the family’s antenatal experience has led to unresolved issues, such as a child not being planned, or health issues of the unborn baby, mother or any other siblings. There is evidence that in-utero environment for babies of mothers with anxiety or depression affects that child’s sleep once born (O’Connor et al, 2007).

Parental biological chronotype –morningness or eveningness (known as chronotype) is determined mainly by genetics and refers to whether a person is naturally more alert in the early morning or evening. 40% of the population are morning types, 30% are evening types and the rest are in between (Walker, 2017). There is some evidence to suggest that morning types report more positivity than evening types (Biss and Hasher, 2015). It may be fair to say though that if a morning-type adult has a child who takes a long time to settle for bed, they will struggle with this. Likewise, an evening-type adult may find early rising in their child particularly hard to deal with. Thus, it is prudent to discuss these aspects with parents and factor them into any suggestions made to improve sleep.

Personality – La Vigouroux et al (2017) looked at the personality types of parents who experience burnout. They found that parents who have difficulty maintaining affectionate relationships with their children, those that struggled to respond to their children’s needs and those who found implementing boundaries hard – were at the most risk of parental burnout. In addition to the above, considering whether parent and child are more extroverts or introverts will also help resolve sleep problems. An introverted parent may find a high-need wired lively child exhausting. Conversely an introverted baby or child may find some parental social occasions or being passed around much more stressful. Both situations will impact upon sleep or perception of sleep problems. Siblings may also factor into this – for example if the new baby or younger child is a different personality type to older sibling(s) the parent may need to use different techniques with each child.

Blog will continue in part 3 where we look at day-time rhythms, naps and family diet.

Rachel Greaves is a midwife, public health nurse and accredited sleep coach. She volunteers at local breastfeeding support groups and works privately at Goodnight Solutions 


Huang, X, Wang. H, Chang. J, Wang. L, Liu. X, Jiang. J, and  An. L (2016) Feeding methods, sleep arrangement, and infant sleep patterns: a Chinese population-based study. World Journal of Paediatrics. 12(1) pp 66-75 Accessed at:

Kendall-Tackett. K, Cong. Z and Hale. T (2011) The Effect of Feeding Method on Sleep Duration, Maternal Well-being, and Postpartum Depression. Clinical Lactation. 2(2) pp22-26

Herman. M, Mowder. B, Yasik. A and Shamah R.  (2012) Parenting Beliefs, Parental Stress, and Social Support Relationships. Journal of Child and Family Studies.21(2) pp190-198

Walker. M (2017) Why we sleep. Chapter 2 Caffeine, jet lag and melatonin. pp13-37 Allen Lane. London.

O’Connor. T Caprariello. P, Robertson Blackmore. E, Gregory. A, Glover. V and Fleming. P and the ALSPAC Study Team. (2007) Prenatal Mood Disturbance Predicts Sleep Problems in Infancy and Toddlerhood  Early Human Development 83(7) Accessed at:

Biss, K and Hasher, L. (2012). Happy as a lark: Morning-type younger and older adults are higher in positive affect. Emotion, 12(3), pp437-441. Accessed at:

Le Vigouroux. S, Scorla. C, Raes. M, Mikolajczak. M and Roskam. I (2017) The big five personality traits and parental burnout: Protective and risk factors. Personality and Individual Differences 119, pp216-219 Accessed at: