Crib or Parents' Bed: The Baby's Perspective on Sleep

In hundreds of societies around the world (and for nearly all of human history), babies sleep with their parents--to do anything else is unthinkable for these families.  Sudden Infant Death Syndrome (or SIDS--where a baby dies in her sleep with no obvious cause; this is also called "crib death") rates are far lower in these societies than they are here in America, and there is evidence that safely sleeping with your baby can actually provide protection from SIDS (and have many other potential benefits for babies and parents).  But here in America, many in the medical community continue to recommend that babies be put to sleep in cribs.  Millions of American parents have agonized while listening to their baby screaming in her crib, hoping desperately that she'll fall asleep.  New parents are routinely told that, if they let their babies sleep in their bed, they will "never get the baby out again." 

We could obviously debate which works better for individual parents.  Some parents can't imagine sleeping with their baby (probably because cribs are so common here), but others rave about how much more sleep they get by having their baby close by for easy nursing and diaper changes, often without the parent having to wake up fully.  But which option best suits what babies expect from their world?

Since babies can't talk, a lot of parenting of babies is based on instinct.  When a baby smiles, it's automatic for parents to want to smile back.  When a baby cries, a mother's hormones kick into gear, often causing tremendous emotional anguish if she is unable to soothe her child.  Many nursing mothers have noticed that when their baby cries, they can feel their milk let down in anticipation of breastfeeding.  Over the course of human history, our minds and bodies have become programmed to respond so that we know how to give our babies the care they need to thrive.  To a large degree, much of how we respond today is the same as it was when humans were still living in caves or outdoors all the time.  And how babies now perceive their world is very similar to babies of that time--which holds the key to how to raise a happy, healthy baby.

In terms of biological drives, a human baby is very similar to other primate babies.  Most primates keep their babies close to them virtually nonstop until the baby is able to be somewhat self-sufficient.  In the "wild," if a baby animal is left alone for more than a few seconds, there is a substantial risk that the baby will be found and harmed by a predator.  So these animal babies--and human babies--call out or cry when they are on their own to essentially alert their parent to where they are and encourage the parent to pick them up. 

Other primate babies are born able to cling to their mothers, so they are already somewhat self-sufficient at birth.  Due to human anatomy, though, our babies are born far more helpless for far longer, so their need for constant protection is even greater than other primates.  From a human baby's perspective, being alone in a crib is no different from being left alone on the ground, which means immediate physical danger.  So the baby cries to call her parents to her, to ensure that they protect her.  If the parents return, all is well--the baby feels secure and can return to her primary job of growing and learning about her world.  If they don't, the baby generally continues to cry, louder and with more insistence, with a desperation that has evolved over thousands of years of life in a dangerous world. 

Many mothers who have dutifully followed their doctor's advice have discovered that it is almost physically painful to leave their baby to cry in a crib.  A close friend of mine, when she had her first child, was planning to allow her daughter to "cry it out" in her crib.  I was trying not to overwhelm her with advice, so I didn't say much except to let her know that I sleep with my babies.  When I talked to her a few weeks later, she said that they had allowed their baby to cry herself to sleep once, and my friend told me, "I am never doing that ever again."  The agony of listening to her child's screams had convinced her that this parenting style was not for her.  Just as babies cry to let us know they need something, parents' bodies (especially for mothers) often tell us how to respond. 

But, some doctors say, babies in cribs eventually stop crying and fall asleep, so it can't be that traumatic for them.  The problem with this theory is that while a baby will eventually give up trying to call her parents to her, the reason she stops crying is not because she suddenly understands that her parents are just in the other room and there aren't any predators around.  Instead, she has come to the conclusion that she has been abandoned, and so there is no point in calling them anymore (or else she has just screamed in distress for so long that she falls asleep from sheer exhaustion).  Studies (incredibly sad ones) of babies whose cries were repeatedly ignored by their parents show children who have become withdrawn and detached--who respond coldly to their parents or don't respond at all.  This sort of extreme detachment can cause lifelong psychological problems. 

This biological basis for sleeping with babies, along with lots of other fascinating things about baby/parent sleep patterns, is discussed by many researchers, including a compelling analysis in the book Our Babies, Ourselves.  Babies (and older children) are very resilient, so one or two incidents where you can't immediately calm your baby are not likely to turn him into a detached, emotionally unavailable adult.  But responding (or not) to your baby's needs does affect her emotional development, her trust of her parents, and her day-to-day contentment. 

As for the concern about getting the baby "out of your bed," millions of parents around the world cosleep with their children until they are three or four years old and even older.  But if this doesn't work for your family, try looking at the situation this way:  If you plan to make your child sleep alone before they choose to on their own, the process is inevitably going to involve tears and emotional distress.  The question is whether you want your child to experience this distress in infancy, while they are still developing their sense of basic security and trust in the world and in you.

Comments

[Harold K.]

Fascinating! I really like the evolutionary biological approach. And, I totally agree with your analysis of the harm done by letting kids "cry themselves to sleep." If and when I ever have kids, I'll certainly have them sleep with me for as long as they like, and pick them up and hold them whenever they cry.

[Nursing Tank]

You have always impressed and this is no different!