Is it Healthy and Safe for Babies to Sleep Alone?­­­­­­­­­­­­­­

Every few months it seems there’s another headline proclaiming “Cry-It-Out Doesn’t Hurt Babies” or “The Dangers of Co-Sleeping.” Doctors warn parents that their child will “never” leave their bed once they let the child sleep there. One public health campaign even compared bed sharing with putting a baby to bed with a butcher knife. All of this can be very upsetting and confusing for parents.

Babies instinctually want to do the natural thing – sleep with someone – and protest when they are put down alone. But Western culture promotes the belief that infants and toddlers “should” sleep alone and frightens parents into thinking that they will harm their children (physically and psychologically) by sharing a bed with them.

Is there any evidence of this? In a word, no – as long as it is done safely and in a biologically normal way (see the Safe Sleep Seven). But really, is that even the right question?

Leading sleep researcher, Dr. James McKenna, explains that many infant sleep studies are backwards, looking at cultural beliefs instead of scientific paradigms. They start with the assumption that solitary infant sleep is normal (it’s not – see my last three posts). These studies usually ask “is co-sleeping/bedsharing safe?” or “does sleep training reduce infant waking and crying?” rather than “is it healthy and safe for babies to sleep alone?”

In fact, McKenna believes that not asking the correct question resulted in a vast cultural experiment that contributed to many babies dying of Sudden Infant Death Syndrome (SIDS). In years past, the untested cultural belief that babies should sleep alone led to doctors telling parents to put infants down on their tummies so they would stay asleep longer. This resulted in huge spikes in SIDS rates that have since fallen with “back to sleep” campaigns.

Artificial (formula) feeding, which made it easier for baby nurses and others to care for infants as night, has also emerged as a major SIDS risk factor. Even solitary sleeping is no longer recommended – a parent’s breathing and other factors help prevent SIDS by stimulating the immature infant respiratory system.

Biologically normal infant sleep components include breastfeeding, sleeping next to the mother and varied sleep positions including side and back. In traditional cultures, sharing sleep takes place on a firm surface, usually the floor (these cultures also have very low SIDS rates).

In Western societies, parents are told to keep infants in their rooms, but never in their beds. Yet, because babies are biologically programmed to seek human contact, warnings against bedsharing often lead to parents falling asleep with their infants on unsafe surfaces such as couches or recliners.

Infant sleeping on unsafe surfaces (which can also include hazards such as mattresses that don’t fit tightly in the frame) is often lumped together with other forms of co-sleeping and even bedsharing in many studies. Unsafe surfaces are also confused as a risk factor for SIDS, rather than for suffocation. But as McKenna and his colleague Lee Gettler note, “…(with) careful and complete examination of death scenes, the results revealed that 99% of bedsharing deaths could be explained by the presence of at least one and usually multiple independent risk factors…such as maternal smoking, prone infant sleep, use of alcohol and/or drugs by the bedsharing adults.”

The authors of Sweet Sleep researched this topic extensively and concluded that there is no greater risk of SIDS when infants under four months old bedshare safely (again, the Safe Sleep Seven) than when they sleep nearby in a crib. And why should there be? Sleep sharing is the biological norm for our species and evolution would have stopped it long ago if it wasn’t safe. Sweet Sleep also states that a baby over four months can safely bedshare with any responsible, sober, non-smoking adult.

In addition to sleeping alone, Western parents are told that infants should be trained to sleep through the night as early as possible. These methods all involve varying amounts of crying to sleep – something that is not biologically normal for our species.

The phenomenon of “extinction” sleep training (a holdover from the discredited psychological theory of behaviorism) is another vast social experiment currently being conducted without evidence that it is healthy and safe for babies. In fact, one study found a disturbing rise in the stress hormone cortisol in infants “crying it out” (chronically elevated cortisol can harm a baby’s developing brain). Even studies that claim the practice is harmless demonstrate no benefits for either parents or babies – and sleep training does shorten breastfeeding duration (again, a SIDS risk factor).

Of course, sometimes babies cry no matter how responsive we are as parents, but holding and comforting babies seems to mitigate the negative effects of this stress. Studies that have looked at social sleeping with one or more parents have found multiple benefits, including increased breastfeeding (more antibodies and other benefits for baby), more rest for both infants and parents and a stronger emotional bond.

In biologically normal sleep, infant and mother often stir without fully waking – baby latches on and both fall back asleep. The parent’s body helps babies wake frequently during the night so they don’t sleep too deeply and stop breathing.

Photo by Sidharth Sircar from Pexels

Advocates of sleep training start with the Western cultural belief that solitary sleep is normal and babies should not disturb their parents at night. Infant night wakings are seen as problematic, rather than protective. Researchers test whether sleep training leads to less crying and fewer awakenings – NOT if this is good for babies.

Again we need to ask – is it healthy and safe for babies to sleep alone? Do parents have to teach their babies to fall asleep? Do parents get more rest if they wean from the breast and sleep train? Does it lead to happier, more independent children? Do sleep trained infants cry less? There is little evidence for any of this and some evidence of the opposite.

There is another way – a way that is normal for our species and has proven benefits, including more sleep for parents and babies. We don’t have to sleep on the ground in the woods, but we do need to avoid hazards associated with our comfortable Western lifestyles. We will look at this in the next What Babies Need.


Douglas PSHill PS. Behavioral sleep interventions in the first six months of life do not improve outcomes for mothers or infants: a systematic review. J Dev Behav Pediatr. 2013 Sept.

McKenna, Ball, and Gettler. Mother–Infant Cosleeping, Breastfeeding and Sudden

Infant Death Syndrome: What Biological Anthropology Has Discovered About Normal Infant Sleep and Pediatric Sleep Medicine. Yearbook of Physical Anthropology, 2007

Middlemiss W, Granger DA, Goldberg WA, Nathans L. Asynchrony of mother-infant hypothalamic-pituitary-adrenal axis activity following extinction of infant crying responses induced during the transition to sleep. Early Human Development. 2012

McKenna & Gettler. Co-Sleeping, Breastfeeding and Sudden Infant Death Syndrome. Encyclopedia on Early Childhood Development. 2010 (online)

Narvaez, D. The Ethics of Early Life Care: The Harms of Sleep Training, Clinical Lactation, 2013

Kendall-Tacket, K.A., Cong, Z., & Hale, T.W. Mother-infant sleep location and nighttime feeding behavior: U.S. data from the Survey of Mothers’ Sleep and Fatigue. Clinical Lactation. 2010

Bartick, M. and Smith, L.J. Speaking Out on Safe Sleep: Evidence-Based Infant Sleep Recommendations. Breastfeeding Medicine. 2014

Whittingham, K. and Douglas, P. Optimizing Parent–Infant Sleep From Birth To 6 Months: A New Paradigm. Infant Ment. Health J., 2014

Middlemiss & Kendall-Tackett, The Science of Mother-Infant Sleep. 2013

McKenna, J. (2007) Sleeping with Your Baby: A Parent’s Guide to Cosleeping.

Pitman, T., Smith, L., West, D., Wiessinger, D. (2014) Sweet Sleep: Nighttime and Naptime Strategies for the Breastfeeding Family. La Leche League International.

News report featuring Dr. McKenna:

Babies Share Sleep in Many Cultures

When my first child was two and a half, she crawled up onto the couch and fell asleep. I was shocked. Really? She can do that? She had never fallen asleep without nursing before.

Western culture tells parents to train children to sleep alone or they will “never” learn to fall asleep by themselves. Even those of us who keep our babies close at night sometimes wonder if they will ever stop needing us.

In many cultures, this isn’t even a question. Sleep is a social event where families sleep together in one room for many years, even in large homes. These societies assume that babies will grow into children, who will eventually fall asleep without nursing or rocking, as of course they do.

Anthropologists often observe contemporary foraging cultures (hunter-gatherers) to determine what is biologically normal for humans. Societies like the !Kung in Botswana (Africa), the Ache in Paraguay (South America), and the Agta in the Philippines (Asia) provide clues into the behavior of our ancient ancestors.

In these cultures, babies sleep next to their mothers at night and nap on someone – a grandparent’s lap, a father’s arms, a cloth tied around their mother’s back – during the day. As the child grows older and perhaps gains a sibling, they might move to sleeping closer to a grandparent or other relative. Only when they reach puberty is there any thought that the child might choose to sleep alone at times.

With these infants and toddlers, no one worries about bedtime rituals or if they are getting enough sleep. These children nurse and fall asleep when they are tired. They snooze in someone’s arms or are put down on a mat or hammock while the family finishes evening activities, then are carried to bed when mom is ready for sleep.

For contemporary foraging cultures, there are generally no separate rooms or heat other than a fire, which could account for these arrangements. But many other industrialized societies around the world have similar childcare practices.

In Korean (and likely other languages as well), there is no word for co-sleeping (sleeping in the same room) or bed-sharing (sharing a mat or bed). It’s assumed that everyone sleeps together on floor mats in the same room, although today mattresses are sometimes added on top of the mats.

Other Asian cultures use similar arrangements. Often the sleeping room serves several purposes – mats and bedding are simply folded up and put away during the day. Floor beds and mats have the added benefit of avoiding hazards such as babies falling out of bed or becoming trapped between a bed frame and mattress.

Interestingly, cultural practices have also contributed to differences in Eastern and Western bedroom furnishings. A preference for carpeted floors and wearing shoes in the house may have led to lifting mattresses off the dirty floor and on to a bed frame in Western houses.

Clean, heated floors, and even a heated sleeping platform called a kang in some parts of China, make floor sleeping comfortable in most Eastern homes. Western houses generally have cold floors, since the air is heated through fireplaces and furnaces.

Even some cultures that do use elevated beds often embrace social sleeping, such as parts of the Middle East and southern Europe. Family interconnectedness is highly valued in these societies. My son spent a semester studying in Barcelona, Spain and often posted videos of late night parades enjoyed by entire families, including young children and babies sleeping in carriers.

Interdependence (rather than independence) and kinship are common values in Eastern societies as well, which also contribute to sleep preferences. In traditional Japanese culture, co-sleeping on tatami mats is compared to a river. The parents are banks on either side, containing, protecting and guiding the water – their child – in the middle.

In fact, this belief in security and comfort for children at night is key for many co-sleeping cultures. Mayan parents in Latin America consider it abusive and unkind to put a baby to sleep in another room. Infants and young children generally fall asleep in someone’s arms and are carried to bed when the rest of the family is ready for sleep.

Parents in Kenya and other parts of Africa believe that it’s dangerous for babies to sleep alone in a separate room. Infants are cuddled, carried and breastfed frequently day and night. Anthropologists note that it’s rare to hear African babies cry, since they are comforted at the breast any time they stir.

It may be time for those of us who live in Western countries to question whether forcing early sleep independence in children really makes sense. If you have ever met an adult immigrant from Africa or Asia or Latin America, you have met someone who probably slept with their parents for years – and became confident and self-reliant enough to travel thousands of miles from home.

So, if shared sleep with babies and children is biologically normal for humans and common in other cultures, why are Western parents so scared to do it? Why do medical professionals and public health officials warn against it? What does the research literature really say? We will look at this in the next What Babies Need.

Ball, H., McKenna, J., Gettler, L. (2007) Yearbook of Physical Anthropology. “Mother–Infant Cosleeping, Breastfeeding and Sudden Infant Death Syndrome: What Biological Anthropology Has Discovered About Normal Infant Sleep and Pediatric Sleep Medicine.”

Biologically Normal Infant Sleep (closed Facebook group), personal communication, May 2018.

Fuentes, A., Gray, P., Narvaez, D., McKenna, J., Valentino, K. eds. (2014) Ancestral Landscapes in Human Evolution: Culture, Childrearing and Social Wellbeing.

Konner, M., Worthman, C. (1980) Nursing frequency, gonadal function, and birth spacing among !Kung hunter-gatherers.  Science. Feb 15;207(4432):788-91.

Liedloff, J. (1986) The Continuum Concept: In Search of Happiness Lost.

McKenna, J. (2007) Sleeping with Your Baby: A Parent’s Guide to Cosleeping.

McKenna, J., Smith, E., Trevathan, W. eds. (2008) Evolutionary Medicine and Health: New Perspectives.

Seockhoon Chung, Hoyoung An. Cultural Issues of Co-Sleeping in Korea. Sleep Med Res. 2014;5 (2): 37-42. Publication Date (Web): 2014 December 30 (Review Article). doi:

Shimizu, M., Park, H., & Greenfield, P. M. (2014). Infant sleeping arrangements and cultural values among contemporary Japanese mothers. Frontiers in Psychology, 5, 718.

Small, M. F. (1999). Our babies, ourselves: How biology and culture shape the way we parent.

Worthman, C. M., & Brown, R. A. (2007). Companionable sleep: Social regulation of sleep and co-sleeping in Egyptian families. Journal of Family Psychology : JFP : Journal of the Division of Family Psychology of the American Psychological Association (Division 43), 21(1), 124–135.

Guest Post: The gentle African way to your baby sleeping through the night

What Happened to Infant Sleep?

Photo via

In many societies around the world, babies sleep next to their mothers. There are no cribs, sleep coaches, sleep training books, baby monitors, swings or other devices to manage a baby’s sleep. They aren’t needed. So what happened to infant sleep in Western culture?

It’s complicated. Sleep in general has undergone a radical transformation over the last two hundred years or so, primarily in response to the availability of artificial light and industrialization. Instead of being guided by the rhythms of the sun and the seasons, many people now stay up late into the night either for entertainment or work.

In times past, sleep was often not the straight through the night phenomenon Western culture considers normal today. There was a “first” and a “second” sleep, broken by a period of quiet wakefulness when people might read or pray, tend the fire, make love, talk quietly or the like before going back to sleep. Daytime naps were common.

However, this sort of rhythm did not suit the demands of factory owners or slaveholders. Industry demanded a long, sometimes irregular work schedule and working slaves to exhaustion served the plantation system.

Emancipation and labor laws have resulted in vast improvements to people’s lives in Western society. Yet sleep is still expected to take place during a single period, usually at night, for those lucky enough to have access to safe, comfortable housing.

In addition, sleep was once a social event not just for families – even total strangers would share beds when they traveled. Less desirable were tenements and slave cabins, where many people crowded together at night made comfortable sleep difficult. Eventually, though, both central heating and a middle class with a higher standard of living made separate bedrooms possible for many.

Other factors also contributed to the rise of separate sleep. Doctors warned of health risks from breathing the air of others and Victorian religious leaders preached of moral dangers (even today, sex is still equated with “sleeping together”), insisting on the privacy and sanctity of the marital bed.

These and other “experts,” who were overwhelmingly white and male, began to assert authority over the traditional wisdom of women in raising children. Most valued independence and self-sufficiency, and warned of the dangers of spoiling children with too much affection. Authorities on childcare also favored formula feeding, a technological innovation that not only allowed parents to feed their infant “scientifically,” but also allowed someone other than the mother to care for a baby at night.

Sadly, one additional factor that may have contributed to the rise of solitary infant sleep were confessions from starving mothers of smothering their infants at night so they would have enough food for their other children. In sermons, horrified priests urged banning infants from the parents’ bed.

So, for a variety of reasons, much of modern Western society has come to believe that solitary infant sleep is normal and beneficial. Parents are told to use cry it out or other extinction sleep training methods to enforce this cultural construct.

Photo by Min An from Pexels

Yet other cultures consider putting a baby in a separate room – or even in a separate bed – not only strange, but akin to child abuse. Contrary to warnings from Western sleep “experts,” these cultures generally produce independent, well-adjusted children and young adults. We will explore the family sleep habits of some of these cultures in the next What Babies Need.



Ball, H., McKenna, J., Gettler, L. (2007) Yearbook of Physical Anthropology. “Mother–Infant Cosleeping, Breastfeeding and Sudden Infant Death Syndrome: What Biological Anthropology Has Discovered About Normal Infant Sleep and Pediatric Sleep Medicine.”


Ekirch, A. Roger. (2005) At Day’s Close: Night in Times Past.


McKenna, J. (2007) Sleeping with Your Baby: A Parent’s Guide to Cosleeping.


McKenna, J., Smith, E., Trevathan, W. eds. (2008) Evolutionary Medicine and Health: New Perspectives.


Pitman, T., Smith, L., West, D., Wiessinger, D. (2014) Sweet Sleep: Nighttime and Naptime Strategies for the Breastfeeding Family. La Leche League International.


Reiss, Benjamin. (2017) Wild Nights: How Taming Sleep Created Our Restless World.

Babies Need to Sleep with Someone

“It is a primitive need of the child to have close and warm contact with another person’s body while falling asleep…. The infant’s biological need for the caretaking adult’s constant presence is disregarded in our Western culture, and children are exposed to long hours of solitude owing to the misconception that it is healthy for the young to sleep … alone.”
-Anna Freud, daughter of Sigmund Freud

Photo via

Where should babies sleep? In Western cultures, like those in the US and Europe, the answer is usually in a crib, by itself, often in another room. But why? Two adults in a romantic relationship often share a bed – how does it make sense that a tiny, vulnerable person has to sleep alone?

In other parts of the world, this is not even a question – babies sleep with someone. Even in Western cultures the idea of solitary infant sleep has only become expected during the last hundred years or so.

Photo via Good Free Photos

To understand biologically normal sleep for human babies, we need to first look at our cousins in the animal kingdom. Some mammals give birth to atricial infants after a short gestation – deaf, hairless and sightless, they develop rapidly in nests or a pouch. Others are precocial, well developed and able to stand or hold on to their mothers almost immediately after birth.

Like many primates, humans are mostly precocial, but also have atricial traits like not being able to walk or cling, mainly due to being born with only 25% of their brain capacity (for more information, see Babies Need to Be Held, 10-14-17). Primate infants even rely on contact with their caregivers to regulate their heart rate, temperature and breathing.

All land mammal mothers sleep close to their babies, although some, like deer and rabbits, have high fat milk that allows them to hide their babies for long periods while they forage for food. The young of these “feed and leave” species don’t cry or defecate in mother’s absence so as not to draw the attention of predators.

Photo via Good Free Photos

However, contact/carry species like marsupials and primates (including humans) do eliminate spontaneously and cry when separated from their mothers. This, along with low fat milk that necessitates frequent feeding, means that these babies need to be kept close at all times, including at night. A human baby who wakes up and cries to protest being alone does so for a very good reason – survival!

In addition to physical regulation, primate infants also need contact for psychological wellbeing. This was first demonstrated by Harry Harlow with his famous experiment in which rhesus monkey babies separated from their mothers clung to a cloth covered “surrogate mother” rather than a wire one that dispensed food. More recent research points to a spike in cortisol in babies left to cry without being comforted, which could effect an infant’s developing brain.

From studying primates and the few remaining hunter-gatherer cultures, anthropologists have concluded that it is biologically normal for a human baby to sleep next to another person, usually it’s mother. So how did solitary infant sleep come to be considered normal and desirable in Western societies? We will explore that in the next What Babies Need.

Liedloff, J. (1986) The Continuum Concept: In Search of Happiness Lost.

McKenna, J. (2007) Sleeping with Your Baby: A Parent’s Guide to Cosleeping.

Pitman, T., Smith, L., West, D., Wiessinger, D. (2014) Sweet Sleep: Nighttime and Naptime Strategies for the Breastfeeding Family. La Leche League International.

Small, M. F. (1999). Our babies, ourselves: How biology and culture shape the way we parent.


Ball, H., McKenna, J., Gettler, L. (2007) Yearbook of Physical Anthropology. “Mother–Infant Cosleeping, Breastfeeding and Sudden Infant Death Syndrome: What Biological Anthropology Has Discovered About Normal Infant Sleep and Pediatric Sleep Medicine.”

Freud, A. (1965). Normality and Pathology in Childhood.

Fuentes, A., Gray, P., Narvaez, D., McKenna, J., Valentino, K. eds. (2014) Ancestral Landscapes in Human Evolution: Culture, Childrearing and Social Wellbeing.

Gettler, L, McKenna, J. (2007) Textbook of Human Lactation. “Mother-Infant Cosleeping with Breastfeeding in the Western Industrialized Context: A Bio-Cultural Perspective.”

Kendall-Tackett, K., Middlemiss, W. (2014) The Science of Mother-Infant Sleep: Current Findings on Bedsharing, Breastfeeding, Sleep Training, and Normal Infant Sleep.

McKenna, J., Smith, E., Trevathan, W. eds. (2008) Evolutionary Medicine and Health: New Perspectives.

Tomori, C. (2017) Nighttime Breastfeeding: An American Cultural Dilemma.

Bed-Sharing and Co-Sleeping: Research Overview

Bodies, Not Buckets

My first child taught me what babies need. She was content only when I carried her. She nursed frequently, sometimes every twenty minutes – a great way to ensure she would be held.

While some infants are content to lie quietly, cooing at a dangling mobile, she would have none of it. As a new mother, I worried – was this normal? Would she be too dependent? Would this go on forever?

Yes, no and no. Today, she is an independent young woman in her twenties, living in a big city and working at a great job. Many friends who parented the same way tell similar stories.

Biologically, human infants are born expecting and needing to be held. A parent’s body regulates the newborn’s temperature and hormones, provides tactile and vestibular stimulation, and keeps baby safe.

Of course, this can sometimes be physically demanding for the baby holder. In times past, and in some societies today, there were always arms ready to receive an infant if the primary parent needed a break.

But in modern Western culture, with single family homes, short maternity leaves, disapproving relatives and pop up ads plugging the latest innovation in carseats, bouncy seats and other baby buckets, how can we give our babies what they need? Here are some ideas:

Prepare a nest

Instead of focusing on cute linens and decorations for a nursery, think about how to make a comfortable place to hold your baby. Maybe a bolster or other firm cushion to lean back on in your bed and a pillow for under your knees? Do you have a good water bottle, a stash of healthy snacks, a place for your books, computer, tablet or phone?

If you have older children, assemble books and puzzles so you can cuddle and play while holding the baby. Be sure your nest is safe if you fall asleep – KellyMom has a good checklist. Often a mattress or firm pad on the floor is the safest and makes it easy for siblings to join you (and if you childproof the room, it will be a great place to relax when your baby begins to crawl and explore).

Adopt the lying-in tradition

Many cultures observe a “lying-in” period of about 40 days where the birthing parent relaxes and holds the baby. One Latin American tradition is called la cuarentena, (the quarantine). In Asia, it’s called “doing the month.”

Traditionally, relatives care for the new mother, feeding her certain foods such as chicken soup with ginger or hot chocolate. Often, warmth is emphasized by bundling up both baby and mom, and avoiding cold foods.

While you might not want to keep your head covered or drink gallons of soup, try to rest with baby as much as you can and accept all offers of help. If anyone asks what they can do, have a list handy: drop off a meal, refill your water bottle, put in a load of laundry. Even if you haven’t given birth, this time to cuddle and bond is priceless.

In the early days, stay in your pajamas or keep a robe handy to signal to guests that you are resting, not entertaining. Leave a cooler on your front porch with a note encouraging visitors to drop off food if you don’t answer the door.

Some parents hire a postpartum doula for part of this period if relatives or friends aren’t readily available. If you go this route, be sure to avoid baby nurses, who care for the baby, not the parent.

If your partner fills this role, but has to return to work after a week or so, ask them to help you prep for the day. Simple things like preparing nutritious snacks and assembling a stack of diapering supplies can keep you comfortable with baby in your nest.

Wear your baby

When you need to get things done or get out of the house, do what parents have been doing for thousands of years – wear your baby. There are many wonderful babywearing options available today, from wraps to slings to structured carriers.

Babywearing International (BWI) has great information on choosing a carrier and there may be a chapter near you where you can meet other parents and try out carriers. Here is their excellent graphic on safe babywearing.

To save money, you can check online for ways to make one yourself or look for used carriers at consignment sales or swap meets (be sure to check for any manufacturer recalls). A simple piece of fabric tied different ways was the first baby carrier and continues to be used around the world.

If you are separated from your baby for long periods due to outside employment or school, try to reconnect by cuddling and wearing your infant when you reunite. As your child gets older, back carriers can be great for making dinner while keeping baby close.

Make baby holding a job

If you have a partner, discuss the importance of baby holding with them. Agree to take turns holding the baby (after a feed, of course) when the other needs a break or to make a quick dinner. Infants normally bond to one parent, particularly if that parent is breastfeeding, so the partner can either take over the task or try putting baby in a carrier and going for a walk.

If you are a single parent, think about friends who might be willing to come over and hold your baby for an hour or so every day or two. If needed, try to find a daycare situation with a caregiver who believes in baby holding and carrying.

Use baby buckets judiciously

In our culture, we all need to use baby buckets occasionally. Driving to the store or work or support group, baby has to be in a car seat. A bouncy seat comes in handy when a parent needs to scoop the cat box or grab a quick shower. Strollers can be wonderful for fresh air and exercise when baby is older and heavier.

Buckets have a purpose, but leaving an infant in one for extended periods of time deprives baby of biologically normal stimulation. If used for naps, any baby holder (a blanket on the floor works too) should be kept in the same room as an adult, according to the American Academy of Pediatrics. Infants tolerate everyday light and noise quite well while sleeping. This sensory input, combined with an adult’s presence, can even reduce the risk of SIDS.


After my first child taught me what babies need, I kept on holding and carrying my other babies. It was overwhelming at times, but I was lucky to have a supportive partner and a mother who lived nearby.

I also found a tribe of like-minded parents who reassured me that this intense time of meeting my babies’ needs wouldn’t spoil them or last forever. And they were right. Babies need human bodies, not buckets.

Babies Need to Be Held

Car seats. Cribs. Bassinets. Strollers/prams. Bouncy seats. In Western culture, “baby buckets” are often considered places where infants should spend their time between feeds and diaper changes. Yet is this normal, biologically speaking?

In modern society, car seats are, of course, essential to newborn safety while driving. Strollers can come in handy when children grow heavier and are happy being pushed on walks. A “bucket” can also be useful when a baby needs to be put down from time to time, although a blanket on the floor can do the trick too.

But too much time in a baby bucket can lead to plagiocephaly (flattening of a newborn’s soft head). Tummy time can help alleviate this problem – but so can holding and carrying, which are what babies need.

When it comes to newborn care, there are four different types of mammals: cache, follow, nest and carry. Cache species like bats and rabbits hide their young and leave them for long periods of time. Milk high in fat and protein allows these animals to return to feed their babies infrequently, sometimes only every 12 hours or so.

As you might expect, follow animals like horses and cows are born mature enough to stand up and walk shortly after birth, following their mothers and nursing about every two hours on milk that is lower in fat and protein. Nest species like dogs and cats have milk that’s in between.

Carry species, of course, carry their babies constantly. The young of these animals, such as apes and marsupials (kangaroos and the like), are frequently quite immature – they need complete protection and almost constant feeding with low fat/protein milk.

Humans are a carry species. Even though we have the largest brains of any primate, our babies are the least neurologically mature and rely on a caregiver for the longest period of time. While most primates are born with a brain between 40-70% the size of an adult’s brain, human babies’ brains are only 25%.

Many anthropologists believe that human newborns began arriving “early” when we began walking upright on two legs. We have huge brains relative to our bodies, and babies need to be born when their heads are small in order to fit through our narrow pelvises. Other scientists theorize that the calories required to grow a human brain in utero are only sustainable for nine months or that complex human brain development needs the stimulation of the outside world.

In any case, it is generally accepted that full-term human babies are born at least three months too early. Many people have heard of the “fourth trimester” – those months following the birth of a full term human infant when they are more like fetuses than babies.

Parents who have experienced this know the blossoming that happens between two and four months of age – the child emerges from a flexed, bean-like position and starts to move more purposefully. A personality, with smiles and sounds, begins to appear.

Particularly during the first few months of life, babies need to be held and fed. A lot. Almost constantly. Marsupials have a pouch for this purpose, but primates instead make a nest with their arms and chest or the infant clings to the parent.

Holding a newborn ensures easy access to food at the breast and also regulates their heart rate, temperature and hormone levels, particularly when skin to skin. The ability of the parent’s chest to stabilize premature infants was first discovered in South America (“kangaroo care”), but physician Nils Bergman writes how a parent is meant to be a full-term newborn’s “habitat” as well.

When carried, infants experience just the right type of vestibular stimulation and other sensory input for optimal brain development, something that just can’t be matched by even the most sophisticated book or toy.

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Another reason babies need to be held is that newborns don’t experience themselves as being separate from the parent. As child development expert Donald Winnicott once said, “There is no such thing as a baby…(there is only) a baby and someone.” The process of separating and becoming an individual involves exploring the world gradually and coming back to the parent to “touch base” many, many times over several years.

Anthropologist Ashley Montagu first coined the word “exerogestation” to refer to the maturation of animals after birth. He believed that for humans, this takes approximately nine months – essentially, babies need to finish gestating in their parent’s arms until they begin to crawl away.

Cultures closest to our hunter-gatherer origins tend to carry their infants almost constantly. Jean Liedoff spent several years living with the Yequana people in South America. Her book, The Continuum Concept, discusses how human babies evolved over millions of years to expect a certain experience for optimal development, which includes near constant carrying by parents, siblings and other relatives.

Dr. Meredith Small’s book, Our Babies, Ourselves, explores the influence of culture on parenting through the lens of several different societies, including the Kung San of South Africa, another hunter-gatherer culture where babies are held continuously.

Photo via Good Free Photos

While our culture still often cautions that we will “spoil” our babies by picking them up and holding them too much, many parents have found that the opposite to be true. Babies nurtured in a biologically normal way put their energy into growing and developing rather than protecting themselves from stress.

They also feel secure enough to grow into independence when ready. Many of us who carried our babies now enjoy secure, loving, independent adult children.

So if holding and carrying are what babies need biologically, how is that possible in our fast paced, materialistic modern world where parents are often forced to separate from their babies for long periods? We will explore this in the next What Babies Need.


Bergman, Nils. “Kangaroo Mother Care.” Accessed October 10, 2017.

Liedoff, Jean. The Continuum Concept. Cambridge, Massachusetts: Perseus, 1985.

Montagu, Ashley. Growing Young. Granby, Massachusetts: Bergin & Garvey, 1989.

Small, Meredith. Our Babies, Ourselves. New York: Random House, 1999.

Trevathan, Wanda. Human Birth: An Evolutionary Perspective. New York: Routledge, 2017.