Co-sleeping: Should I be worried?
Updated: Sep 14
Pediatricians and child psychologists get this question often: Should I let my child sleep with me? Parents often wonder if sleeping with their child may make things "worse" in the long run. Will it hurt the child's ability to self-soothe? Will they ever sleep on their own? Am I condemning them to a lifetime of being unable to be alone at night?
Well, in short, the science on co-sleeping in early childhood actually shows no meaningful correlations one way or the other. In other words, young children (under age 5) who sleep with their parents either regularly or on occasion do not have any higher likelihood of having behavioral, emotional, cognitive, or other problems when compared to kids who slept alone. At the same time, kids that co-slept also don't seem to be more likely to be "better off" than kids that didn't in any reliable category. These findings are especially true after you control for all the other things that explain correlations between early childhood co-sleeping and later behavioral or emotional difficulties. For example, young children with high anxiety are both more likely to co-sleep on occasion with parents and more likely to have high anxiety later in life. In this case, the common factor is the child's predisposition to anxiety, not the fact that they co-slept. Similarly, sleep problems are common in many childhood psychiatric disorders, and children with sleep problems early on may more frequently request co-sleeping. So, again, in this case, the common factor is a pre-existing psychiatric disorder causing sleep problems, rather than the other way around.
So, the first thing parents should know is that deciding to co-sleep with your child is not likely to cause them any issues later in life, and fear of causing problems should not be a reason to decide not to co-sleep. There may, however, be other valid reasons not to co-sleep, which we'll look at below. First, though, let's spend a little time looking at what safe co-sleeping is across early childhood.
Co-sleeping in infancy
Importantly, co-sleeping in infancy does not mean sharing a bed with your infant. While we've all done it as parents, and fallen asleep briefly beside our baby unintentionally (or perhaps, sometimes, intentionally), the safest way we can co-sleep with our babies is to sleep in the same room as them or have them sleep in a bassinet next to our own bed. Sharing a bed with infants, especially infants too young to reliably roll over, can be dangerous and contribute to risk of SIDS (Sudden Infant Death Syndrome), which is most frequently caused by suffocation due to improper sleeping position or improper sleep environment. Bed sharing is almost never the safest idea for infants, as, once asleep, we adults can roll onto our infants, or cover their face with our blankets, or even place a hand on their chest and restrict breathing. All of these things are unnecessary risks when we have the option of simply placing our children in a nearby bassinet when they sleep with us. Thus, if you're going to co-sleep in infancy - which is very common, and, in fact, perhaps among the best scenarios for optimizing your infant's mental health - do not share a bed. Instead, place the infant in the same room as you, in a different, baby-safe bed.
And remember, when your baby is sleeping, back is best (lay them on their back to sleep, swaddled or well clothed in pajamas). To keep them from getting too hot, keep the room cool (which I know is sometimes easier said than done. My daughter was born in Texas and spent infancy in a home without central heating and air). Keeping them cool reduces further risk of SIDS. Cool doesn't mean cold though. Don't put them right next to the forced cold air. But don't worry too much, babies are very good at letting you know when they're uncomfortable. =) Lastly, don't put anything in their crib that they can roll up against and that may cover their face if they do happen to roll up against it (such as blankets or pillows or stuffed animals)
Once your infant can reliably roll over on their own and successfully free themselves from anything that may cover their face, you can be a little more liberal about allowing them a nighttime "lovey" or stuffed animal. Ask your pediatrician about when your child is ready for this!
Co-sleeping after infancy
As children get older, you may begin to allow your child to sleep in your bed. Again, ask your pediatrician about when this may be allowed and the safest way to do it, as different children may have different risk factors that may need to be considered at different ages.
When is bed-sharing or co-sleeping a problem
A very common reason (in my experience, anyway) to stop co-sleeping is because parents often don't sleep well with a restless child next to them, and a tired parent is often a less effective parent in other realms. Personally, I get physically ill when I haven't slept well, which then gets in the way of work as well as other daily activities of life. So, many parents may decide to transition their child to their own room as a means to get better sleep themselves.
Another common reason to stop co-sleeping is because, well, parents often want to do, let's say "private" things in the bedroom after kids are asleep. Having a child in the same room (and especially the same bed) as you causes problems with that, some of which may land you in a whole heap of other types of troubles. Parents deserve privacy, and nighttime is, for most parents, the only reasonable time to actually get that privacy in their own home. So, it can be reasonable to kick your kid out to their own room just so you can get that much needed privacy.
Many parents transition away from co-sleeping early so that they can avoid a more difficult transition later. Though rare, some children become dependent on co-sleeping and find, even in late childhood (age 9-12) that they are unable to feel secure at night without having someone near to them. Fortunately, in such children, there are simple interventions that can get them, eventually, to sleep on their own, but bigger children are able to engage in bigger protestations of learning to sleep alone, which can make the transition louder, more disruptive, and more difficult. For this reason, and because U.S. cultural norms press parents to do so, many parents in the U.S. transition their children to their own room early, as early, in some, as 3-4 months.
A 2017 study looked at some of these trends and actually found that infants who transitioned to their own room at 4 months (compared to a later transition, say at 9 or 12 months) slept a little better later on (e.g. at 9 or 12 months), even though these differences washed out by toddlerhood. Though the exact timing of the transition during infancy does not appear to be terribly important in the long term, most parents end up transitioning children to their own room by 12 months of age. And this means that most children in the U.S. will be accustomed to sleeping in their own room well before preschool. As a result, many children who co-sleep with their parents past preschool may experience mild symptoms of shame or guilt about the practice, especially as they grow into later elementary school years, where they begin comparing themselves to peers at greater rates. Once such children develop this capacity for social comparison, they may experience ambivalent feelings about wanting to sleep on their own versus being anxious about transitioning away from something they're used to (co-sleeping). Most children, still, are able to navigate the transition well on their own. Others benefit from professional help. In either case, there will come a time when children, invariably, will eventually need to transition to sleeping in their own bed. The next section, then, is dedicated to offering guidance on this transition.
How to transition from co-sleeping to sleeping alone
Once you or your child makes a decision to sleep alone, you now must decide how to go about it. In infancy, early on, the process usually happens rather unceremoniously, though, for many, not without difficulty. In later childhood, it helps to make the transition into a celebration, hosting a "party" of sorts to celebrate the move - like a birthday party. In children who resist the "natural" version of this process, more clinical intervention may be needed. We'll look at each independently below.
Transitioning for infants
For infants under 1 year, throwing a "party" to celebrate the transition to sleeping alone probably won't be very meaningful for your child (though it could be fun for you!). Honestly, most parents just decide to make the transition one night and just do it. That's not as easy as it sounds though. You can expect during the initial transition a mild to moderate increase in distress for your infant, and perhaps some difficulty falling and staying asleep. First-time parents are often amazed at how much their little babies notice, and they will certainly notice that you're suddenly further away at night, and, for some babies, this can be stressful. But don't let that deter you from going through with the transition. Some stress is actually good for babies brains and helps them build confidence early on that stress can be managed, with the right supports. So, there are a few things you can do to support your baby's stress during this transition.
First, don't practice the "cry it out" method. Often referred to as "The Ferber Method," after the pediatric doctor that first described it in a now-famous book, the "cry it out" method is often discouraged because many parents can inadvertently take it to an extreme and leave their baby to cry for extended periods (even at young ages) without responding to them. I will admit, I have never actually read "The Ferber Method" book, and thus cannot comment on the actual method or how it is intended to work. It's possible that the actual method itself is not as extreme as it seems on the surface. I genuinely don't know. The problem, though, is that many parents also have not actually read the book. Instead, they hear about the "cry it out" method and decide to try it out as it sounds, by not responding to their child's cries at night at all. Most parents are doing this with good intentions. They are following a doctor's advice and trying to do what they think is best for their baby. But, in reality, babies are evolutionarily designed to be soothed when they cry. Think about our ancestors who were raised "in the wild," without the secure amenities of the modern world. A crying baby in the jungle often made an easy target for predators at night, or, during the day, could attract other unwanted attention or scare off prey that would be vital to the survival of a tribe. Our species spent hundreds of thousands of years, then, building brains that were optimized when crying prompted parents to soothe children. In other words, biologically, our brains are pre-wired to be soothed when distressed.
When babies cry for extended periods without being soothed, they will eventually stop crying, yes, but this also, when taken to the extreme, leads to serious neglect and extremely difficult-to-treat long-term psychiatric complications called "attachment disorders" (the real attachment disorders, I mean, not the stuff you hear about from non-specialists who claim that every behaviorally and emotionally disruptive child has an attachment disorder - but that is, perhaps, another topic for another blog). Such genuine attachment disorders are rare - it's actually hard to neglect a baby enough to cause these disorders. But still, the point is that the goal of sleep training is to optimize a baby's sense of security so that they can experience soothing without always relying on a parent or other adult to "bail them out." At the same time, a secure baby understands that parents will come help if things get bad enough. So, balance is the key.
Thus, this means you do not have to jump at every sound a baby makes, but you should be ready to help them soothe when they really need. Our brains also need to learn some self-regulatory capacities, and infancy is the best time to do this, while the brain is still growing and pruning neurons to shape later functioning. So, I typically recommend some variation of the following steps in transitioning your baby to sleep alone.
1) Start by putting your baby down in their bed when they're drowsy, but BEFORE THEY FALL ASLEEP, so they can get the experience of laying down while awake. Your baby will cry at first. They won't like you putting them down, but give it a few minutes and stay with them, perhaps offering them your hand if they cry.
2) Maintain physical contact until they start to wind down and get drowsy again. Once they are calm and seem almost asleep, try to get up and walk out. If they don't complain, great. Give yourself a silent little fist pump when you leave the room! You earned it.
3) If they do complain when you walk out, give it another few minutes to see if they stop. If they haven't stopped within a few minutes (3-5 minutes), go back and start over at step 2. If, with step 2, they still haven't calmed after, say, another 5-10 minutes (depends on the intensity of their cry - if it's intense, a shorter wait makes more sense), pick them up and start over with step 1, rocking them until they're calm and ready to lay down. Then, progress again through steps 2 and 3.
That's basically it, just repeating those steps over and over again until it clicks and they sleep through the night. Most times, you'll have to repeat this again when they wake in the middle of the night. Some babies will get it faster than others. Some babies (and lucky parents) get it in days, others may take many months. For those that take longer, just be patient and stick with it. Building healthy brains takes time, and don't get discouraged that you're doing something wrong. Some babies just resist this more than others.
When babies resist
The most common resistance to this process takes place anywhere between 4 and 8 months, when babies start to experience normal separation anxiety. The easiest answer to this is one I used with my own daughter. I simply gave her the t-shirt I wore that day and placed it like a sheet underneath her to sleep on. My scent on the shirt was enough to reassure her I was near. My wife did the same sometimes. For older children, separation anxiety can also be managed with other "replacement objects" - that is, things that remind them of parents when parents aren't around, including stuffed animals, pictures, or other rituals. I really like the book The Kissing Hand, by Audrey Penn, which is a great bedtime story to read with kids that helps cope with normal separation anxiety.
Another common time of increased nocturnal distress happens when babies start teething. Those sharp little teeth erupting through gums can be pretty uncomfortable, and can cause babies to need more soothing than usual. Thus, if you go through an extended period of hardship with sleeping alone at night (>5 in a week), check those little gums for signs of teething. Or look for other signs of teething, like increased drooling, chewing on/mouthing objects, etc. If teething is the culprit, well, you may just be in for some hard nights until the process is done. You can try other techniques to soothe teething too. Ask your pediatrician about those.
A third reason for resistance to sleep training is inconsistency in the method above. It may be that not all caregivers are following the plan each time. In order for it to work, you should aim for at least 85% consistency. That 15% inconsistency allows for about 4-5 days each month (or once a week) for you to have "an off night," where you're just so desperate for peace and/or sleep yourself that you maybe just rock your baby all the way to sleep instead of putting them down while drowsy. Don't feel bad if that happens. That's called parenting, and it's happened to all of us for millennia. But if you're doing well with the program, but your partner isn't, then that can actually cause more resistance across the board. If you and your partner are having trouble getting on the same page, consider a sit down with a mediator to try to work out a proper balance and work through any resistance from either side on adhering to the sleep training protocol.
Transitioning older children
The process for transitioning older children to is very similar to that used in infancy, though the details look a little different. For example, in most older children, parents are rarely rocking them until drowsy and then putting them in bed. Similarly, older children, especially if they are old enough to speak fluently, are able protest sleeping alone in ever-increasingly interesting (and sometimes loud) ways. Trust me, there's quite an amazing difference between the cries of a 4-6 month-old compared to those of a 2-3 year old. And when kids are older, 4+, they can do more than just cry - they can negotiate and plead and do all kinds of other things that will pull at your parent heartstrings to make you give in and let them sleep with you. Still, like with infants, if you come prepared with a plan, your child can make the transition eventually.
My first recommendation for transitioning older children to their own room is to make it into a fun celebration. Do everything you can to boost the excitement about the move. If you can afford it, buy a new bed and/or let the child decorate the room in a way that comforts them. Add a new pair of sheets or blankets, chosen by your child. Don't be afraid, if necessary, to plaster your child's walls with pictures of whatever images they can conjure that help them feel safe and/or happy at night. These can include photos of you (parents) and/or siblings, drawings of heroes or other favorite characters, or really anything else they choose. It may look a little ridiculous, even, but poor aesthetics is a small price to pay when it comes to the pride you and your child will feel at a successful night's sleep. Allow your child also to choose a buddy (old or new) - a toy or stuffed animal they can use to snuggle with at night. Interestingly, snuggling is a biological need that often outweighs other needs, like food and water (to learn more, check out Harry Harlow's early experiments on this with monkeys), and a "replacement" snuggle (something soft) can often work wonders in releasing calming, relaxing hormones in your child's brain to help stimulate peaceful sleep.
Once the room is prepared, plan a party or some other big spectacle to celebrate the event. Think what you would do for a birthday party, and do something similar. Your child will enjoy the excitement of it all, which will help quell some of the anxiety they may have about sleeping alone. This party should happen the same day as you plan for your child to sleep alone, and should not be contingent on whether or not they do sleep alone. In other words, the party should happen regardless of whether or not they actually sleep alone later.
Plan some rewards for after your child succeeds. These can be small rewards, nothing crazy - just something to let them know you're proud of them and to congratulate them for a good job. Make this an easy-to-obtain reward at first. In other words, if the child usually has never slept at all in a bed alone, reward them if they stay for an hour or two. Don't be hard on them if they don't make it the whole night, but focus on rewarding the successes. If the child is used to staying half the night, reward them for staying 5+ hours. You can individualize it as needed. The point is that the child feels rewarded for their work and that, if they don't make it, they don't feel punished for not making it, which only increases anxiety. Just calmly tell them, "that's okay, we'll try again tonight," and keep at it. Eventually, in most kids, they'll eventually settle in and get through it.