Mother Holding Sleeping Baby

Sleep Associations

Sleep Associations

If your baby is lacking sleep, one of the most helpful things you can do is to identify his sleep associations and learn what impact these have on his ability to sleep. Read on to discover what sleep associations are and their effect.

Baby sleep associations

Some of the many conditions, activities and props that babies learn to associate with sleeping include:

  • Crib or bassinet (but only if baby falls asleep while in his crib or bassinet).
  • Physical contact with a parent or caregiver; e.g. cuddled in a parent’s arms (upright or vertical), laying on a parent’s chest or next to a parent while bed sharing.
  • Carried in a parent’s arms or a sling.
  • Feeding to sleep - breast or bottle.
  • Being patted, stroked, jiggled or bounced.
  • Rocked in a baby rocker, swing, hammock or stroller.
  • Movement whilst driven in a car.
  • Swaddled, or dressed in a baby sleep sack.
  • Music, radio, white noise, womb-like sounds, or shushing.
  • Sucking on a pacifier.
  • Clutching a security blanket or soft toy.

If you can identify your baby’s preferred way to fall sleep, it’s likely that these involve his sleep associations. 

Why babies behave differently 

Individual babies differ in their response to sleep associations depending on each baby’s level of awareness and sensitivity to change. 


The impact of sleep associations becomes increasingly more evident as a baby matures and thus becomes progressively more aware of his surroundings. 

The younger your baby, the less aware he is of the absence of his sleep associations during sleep. In the early weeks, you might find that you can help him fall asleep, move him or remove your help (thus removing his sleep associations) and he continues sleeping for long enough to get the amount of sleep he needs. However, this may or may not remain the case as he matures. The situation could change at any point in time because of advancements in brain development, which enhance his level of awareness and ability to perceive change.

Babies go through an intellectual growth spurt around the age of 4 months. As a consequence, their ability to sense change in their surroundings while awake and during light sleep expands. Baby suddenly becomes more distractible during daytime feeds and more wakeful at the night. What is often called ‘4-month sleep regression’ is increased wakefulness due to a baby’s enhanced ability to sense changes in his sleeping environment and sleep associations during light sleep.


Two babies of the same age, for example twins, could be settled to sleep in exactly the same way and yet each baby’s ability to fall asleep and remain asleep may be different, simply because of each baby’s temperament. Some babies are more sensitive to their surroundings and inconsistencies in the care they receive compared to others. An example of inconsistency is teaching your baby to rely on certain sleep associations and unknowingly withholding these at the time he’s ready to sleep, or removing his sleep associations after he has fallen asleep. As parents, we all provide inconsistencies in care at times, usually without realizing it. 

Approximately 45 percent of babies have an easy-going temperament. They tend to sleep well, regardless of what parents do or don’t do when settling them to sleep. At around 4 months of age, like all babies, they become increasingly more aware of changes to their sleeping conditions, but are not necessarily troubled by this, especially if the change is small. They might experience minor sleeping problems, but generally not to the extent that worries their parents. Easy-going babies don’t tend to complain, at least not much, when they don’t get enough sleep. 

The remaining 55 percent of babies are more sensitive to change. Some more so than others. The more sensitive a baby is to change, the more likely it is he will experience sleeping problems related to sleep associations. Sensitive babies as young as 4-5 days of age can be negatively affected by the absence of learned sleep associations at the time they’re ready to sleep, and the loss of, or change to, their sleep associations during sleep. Sensitive babies are more likely to be affected by sleep problems and more inclined to fuss, whine, cry or scream - depending on their level of tiredness - compared to babies with easy-going temperaments. (See Temperament for more). 

Type of sleep associations

How aware a baby is of changes in sleeping conditions also varies depending on the type of sleep associations he learns to rely on. Some babies are exposed to greater change during sleep compared to others. Max and Amelia provide examples. 

Max is 3 months old. He is placed into his crib tired but awake and patted to sleep. He naps well during the day and wakes only once during the night to feed. The only change in Max’s sleep associations is that his mother stops patting him once he is asleep. While Max fusses if he’s not patted to sleep, he doesn’t appear to be troubled by the loss of this sleep association during sleep. Perhaps Max has an easy-going temperament. Or perhaps he’s not acutely aware of the changing conditions at his current stage of development. As Max matures it’s possible that he could start to wake during his sleep and fuss or cry to be patted back to sleep.

Amelia is also 3 months old. She’s settled to sleep whilst being cuddled in an upright position in her mother’s arms as her mother sits and bounces on a yoga ball. Amelia also sucks on a pacifier as she falls asleep. Once asleep, she’s placed into her crib. She doesn’t notice the change in conditions when she’s deeply asleep. However, when she next enters into light sleep she senses that she’s no longer in her mother’s arms and no longer being bounced. She’s flat on her back and her pacifier has fallen out.  So she wakes and cries even before opening her eyes, upset by the loss of her sleep associations.  Amelia is not necessarily more sensitive than Max, but the changes to her sleeping conditions are more significant compared to what Max experiences. 

How babies learn sleep associations

Learning by association is the most basic form of learning. It only requires repetition for us to form a connection between two things. Babies learn sleep associations within days or weeks following birth. 

Whether you realize it or not, you have been teaching your baby how to sleep from the time of his birth. The actions you take or don’t take at the time he falls asleep will either encourage or discourage him from associating certain conditions with sleeping.

When a baby is repeatedly settled to sleep in the same way, he learns to link these conditions with sleeping. This then becomes his preferred way to sleep. Or in the case of a sensitive baby, it can become the only way he wants to sleep.

Your baby will make this connection whether you’re aware or not. If you’re not conscious of what you’re teaching him (by the way you settle him to sleep) then the sleep associations that he learns to rely on won’t necessarily be ones you want him to learn.

How sleep associations affect a baby's sleep 

Sleep associations can have a profound effect on a baby’s ability to sleep. Infinitely more than most parents and health professionals are aware. The presence or absence of a baby’s sleep associations can influence how easily he falls asleep and whether he remains asleep long enough to have his sleep needs met or wakes too soon.

Falling asleep

Unlike you, your baby cannot take himself off to bed and set up his environment and sleep associations when he’s tired. He relies you or another caregiver to provide these.

Once your baby has learned to associate certain conditions with sleeping, when tired he will fuss and cry for these to be provided. If his sleep associations are made available to him at this time, he will drop off to sleep relatively quickly. However, if his sleep associations are withheld - perhaps because you have overlooked his signs of tiredness or misinterpreted these as hunger, boredom or pain, or because you were unaware that he has learned to rely on certain sleep associations to fall asleep, he may remain awake despite his readiness to sleep. The longer he’s denied his sleep associations, the more tired he becomes, the more he fusses and the greater the risk he will reach the point of distress due to overtiredness.

Remaining asleep

The presence of a baby’s familiar sleep associations doesn’t just help him to fall asleep, they also support him to remain asleep for as long as he needs to wake refreshed. He might wake sooner if he has a physical need that requires attention, but the risk of waking too soon is significantly reduced. 

If your baby’s sleep associations are absent or change in some way after he falls asleep, he’s at increased risk of waking prematurely from his sleep. But only if he notices the change. He’s probably not going to notice the loss of his sleep associations while he’s in a deep sleep stage of a sleep cycle, but when he next enters into light sleep he might notice. He’s likely to wake if he senses a change to his sleep associations. If he has not had enough sleep, he will either wake cranky or quickly become that way owing to tiredness. 

How this changes according to level of fatigue

Once a baby has learned to rely on particular sleep associations, he may resist falling asleep and wake too soon without them. When sleep is delayed or broken owing to the absence of his sleep associations, this can cause a sleep debt. If this occurs a number of times throughout the day, his sleep debt will accumulate. By the evening he could reach the point of overtiredness. Once overtired, his little body will start to release stress hormones that make it difficult for him to fall asleep, even if his sleep associations are present at that time. After what could be many hours of fussing and crying due to the stress associated with overtiredness, eventually he falls asleep as physical exhaustion overpowers him. Once asleep, a newborn baby might remain asleep for an extended period of time, too exhausted to notice or care if his sleep associations are present or not. Whereas a baby over the age of 4 months might wake multiple times during the night if his sleep associations are missing. 

Baby care problems related to sleep associations

Despite having worked for many years in pediatrics and midwifery, I didn’t know about the effects of sleep associations on a baby’s ability to sleep when my children were babies. Now, as a child health nurse specializing in assisting parents to resolve well baby care problems, I find that most parents and health professionals are unaware. The fact is, we don’t know what we don’t know.

As a result, as parents, we accidentally teach baby to rely on certain sleep associations…. and then unknowingly withhold his sleep associations at times he needs to be sleeping…. and then mistakenly blame hunger or pain as the reason for his excessive awakenings, his frustration when he discovers his sleep associations are missing, and his distress if he becomes sleep deprived as a result. But this is not where the story ends.

What begins as a sleeping problem can become progressively more complex depending on the actions we take. Mistaken assumptions about the cause of baby’s crying, wakeful behavior can trigger a chain of events that leads to bigger problems for baby and even more stress for parents.

Hunger is the first thing suspected for a baby’s wakefulness. And so we try to get baby to eat more. We offer baby both breasts at each feed; give him formula in addition to breastfeeds; increase the amount of formula in his bottles or try to make him drink more; we add cereal to his bottles; or start giving him solid foods sooner than recommended. All in a bid to get him to sleep more. If baby is younger than 3 months, these actions could cause him to overfeed owing to the presence of his sucking reflex. If more food fails to resolve his sleeping problems (which it will if the reason is missing sleep associations and not hunger). Or our actions makes the situation worse by causing baby to suffer gastro-intestinal discomfort related to overfeeding (see Lactose Overload for symptoms) we’re going to worry that pain is the cause of his wakefulness and distress.

Being responsible parents, we take our distressed, wakeful little baby to be seen by doctor. The doctor examines baby but can’t see anything abnormal, and so bases his/her assessment on our description of baby’s troubled behavior and any gastro-intestinal symptoms we describe. Doctors are trained to diagnose medical conditions. They are generally not trained to provide parenting education and are in general unaware of the impact that sleep associations on a baby’s ability to sleep, or that parents commonly mistake their baby’s wakefulness as hunger and therefore risk overfeeding their newborn babies. And so the doctor asks no questions about baby’s feeding or sleeping habits or our infant feeding or settling practices.  Consequently, baby is diagnosed with a physical problem such as teething, colic, reflux, or milk allergy or intolerance.

Baby is prescribed medications and/ or we’re advised to change his diet (or his mother diet if baby is breastfed) in the hope of relieving suspected pain. Some treatments may inadvertently minimize gastro-intestinal symptoms linked to overfeeding, as so appear to improve the situation. But they will fail to address sleepless, wakeful behavior related to the absence of baby’s sleep associations, and so baby continues to be upset due to unmet sleep needs. 

Alternatively, if the doctor is aware of sleep association problems, time restraints means he/she is limited to providing simplistic advice to leave baby to cry it out.  Something most of us object to doing, especially if we’ve become convinced that baby is suffering from pain. So we go to see another doctor, and another, with hope that one will provide a solution that relieves baby’s distress. It may not be until months later that we start to question what these health professionals are missing.

This does not imply that all infant sleep problems are due to sleep association issues or that babies don’t wake prematurely from sleep because of hunger or pain due to physical problems such as those listed. Babies can, and do, wake for these reasons. I simply suggest that failure to provide a baby’s sleep associations at the time he needs to sleep and for as long as he needs to sleep are THE MOST common reasons for brief or non-existent naps during the day and frequent and excessive awakenings at night, and distress displayed by healthy, thriving babies. And that overfeeding can add an additional layer of distress to an already sleep-deprived little baby.

Problems are not limited to one per baby. Problems can co-exist. When a baby is genuinely troubled by a medical condition this doesn’t mean he gets a free pass when it comes to sleeping problems related to sleep associations or any other sleeping or feeding problem commonly experienced by non-affected babies.

Months of distress suffered by babies and parents could potentially be avoided if parents were made aware of the effects of sleep associations before their baby was born. They would then be in a position to make an informed decision about which sleep associations they wanted to encourage their baby to learn. Seldom are parents told. In most cases they have to discover this for themselves…. or not. If not, they may have no option other than to survive years of baby and toddler behavioral problems related to poor sleep. It is for this reason that I have written this article on sleep associations and a book on infant.

Your choice

It is never too late, nor too early, to resolve a problem that is causing a baby distress. Now that you know just how influential sleep associations are, you might have a decision to make. 

Option 1: You could do nothing different in regards to the way you manage your baby’s sleep and live with the consequences. If there is no problem, then there is no need for you to do anything different. Or you might choose this option if your baby’s sleeping problem is causing only minor inconvenience. 

Option 2: You could identify your baby’s sleep associations, provide all of these at the time he’s ready to sleep and choose to either maintain his sleep associations throughout the entire time he needs to sleep or identify when he wakes too soon and help him to return to sleep by returning sleep associations. Depending on your baby’s sleep associations, his sensitivity to changing conditions, and your responsibilities, this may or may not be achievable over the long term. 

Option 3: You could change your baby’s sleep associations to ones that can be maintained throughout his entire sleep. There are numerous ways to achieve this. But be aware that, change for change sake is not necessarily going to be helpful. You need to have a clear understanding about how your actions will influence your baby’s sleep…. for better or worse. 

Written by Rowena Bennett.

© Copyright 2020. All rights reserved. Permission from author must be obtained to copy or reproduce any part of this article.

Your Sleepless Baby book

My infant sleep book called ‘Your Sleepless Baby: The Rescue Guide' provides a comprehensive guide on the many reasons and solutions for infant sleep problems. Included is detailed information on sleeping problems related to sleep associations. Also included is information on how to identify and resolve other reasons for sleep disturbance. There is a range for infant settling options to suit babies of differing ages and temperament types, and to match various parenting styles.