Safe co-sleeping: when your baby just won’t sleep alone

Co-sleeping: when your baby just won’t sleep alone

Woman lying on her bed, on her side. Her baby is lying next to her on the bed. Image shows safe co-sleeping positioning

How common is co-sleeping?

Co-sleeping, also known as bed-sharing, is where a parent and baby sleep in the same bed. Co-sleeping has been common practice among humans for millennia. In most of the non-Western world babies, toddlers and children sleep close to their parents. Even in the West, until very recent history (the last 150 years or so), most families slept together in close quarters. Co-sleeping is not something unique to humans either. Look at any mammals caring for their young, and you’ll see them snuggled up together for sleep. And yet, in the West today, co-sleeping is not really culturally acceptable. 

The message you often get is that you cannot co-sleep safely. As a result, co-sleeping It is something that is usually done clandestinely, something that we admit to shamefacedly, or deny altogether. Depending on who your health care professional is, they may issue an ultimatum to NEVER co-sleep. But is a blanket ban on co-sleeping the safest approach? 

What is my experience of co-sleeping? 

I was a midwife for 15 years. During that time I did a lot of home visits. My safe sleep speech always started something like this:

The safest place for your baby to sleep is in his/her own sleep space, in the same room as you for the first six months. Some families choose to co-sleep. If you decide to do this, then the safest way to do this is…”

Invariably, the new parents would shake their heads earnestly and say “Oh, no! We’d never co-sleep.” In fact, in the 15 years I was a midwife, I never had anyone admit that they were planning to co-sleep, or even they had done it accidentally

The problem with that whole scenario is that it’s just not what happens in reality. I know (as a parent) that the vast majority of my friends have co-slept with their babies at some point, whether intentionally or whether it happened accidentally because they just were so tired that they fell asleep with their babies in bed with them. 

I’ll admit that I co-slept with both of my children from birth for several years. I stopped co-sleeping with my daughter when she was four because I had a baby on the way. She’d still sneak into my room frequently at night and slept there for several years after that. The irony is that now (at the age of 10) she refuses to even share a hotel room with her family when on holiday!! 

It’s dangerous NOT to discuss co-sleeping

If we don’t have an honest and frank discussion about co-sleeping and how common-place it really is, then we can’t address the safety issues. There are cultures (like Japan) where co-sleeping is the cultural norm and the SIDS rate is very low. In order to make co-sleeping safe, we need to discuss it. If it’s not something you’ve considered or planned for, then you are less likely to co-sleep safely. 

Ultimately, an adult bed is designed for adults to sleep in, and in order to minimize the risk factors, we need to actually admit that co-sleeping is happening, all around the world, and also, much closer to home! We need to admit that co-sleeping often makes life, sleep and breastfeeding much easier, and that it’s going to happen, no matter what parents are told. Having a new baby is exhausting, and often co-sleeping happens out of desperation. When you haven’t planned to co-sleep, there is a higher risk of it not happening in a way that is safe. 

This blog will look at: 

  • the benefits of co-sleeping, 
  • potential risk factors,
  • how to co-sleep safely.
Woman is sleeping in bed with her baby.
Photo taken from the BASIS co-sleeping image archive. Click on the photo to see more examples of safe co-sleeping.

Benefits of co-sleeping

Improved sleep for babies

One of the primary benefits of co-sleeping is that babies usually sleep better when close to their parents. After all, this is one of the reasons why parents resort to co-sleeping in the first place! The proximity to their caregivers provides a sense of safety. Babies need contact with an adult to regulate their emotional state. When babies are in contact with an adult, their nervous system recognises that they are safe and secure. This in turn promotes a more relaxed state of sleep. Babies who co-sleep will often link their sleep cycles independently, or need less support to fall back to sleep when they do stir. 

Improved sleep for parents

Co-sleeping can also contribute to increased sleep for parents. When a baby is in close proximity, parents can quickly respond to their needs, such as feeding or soothing, without having to fully wake up or leave their bed. This proximity allows for easier nighttime caregiving, leading to better quality and quantity of sleep for parents. Of course, this isn’t the case for all parents and some parents really can’t sleep at all with their baby in bed with them. If this is you, then read my next blog on how to stop co-sleeping! 

Easier resettling

Babies who co-sleep tend to settle back to sleep more easily. Instead of waking up fully and becoming distressed when they need attention, they can be easily comforted by a gentle pat, a soothing word, or breastfeeding. This can help both parents and babies return to sleep more quickly, reducing sleep disruption for the entire family.

Prolonged duration of breastfeeding

Co-sleeping facilitates breastfeeding by making nighttime feeds more accessible and convenient. Mothers who co-sleep can breastfeed their infants while lying on their side, which allows for a more relaxed and comfortable feeding experience. 

Dr James McKenna (2020) coined the phrase “breastsleeping”. This is where mum and baby synchronise their sleep patterns. Mum is aware that baby is stirring, she latches the baby on without fully waking, they both doze throughout the feed, and then they both fall back to sleep quickly and easily. 

This increased accessibility and ease of breastfeeding often lead to a longer duration of breastfeeding (Ball, 2007), which offers numerous health benefits to both babies and mothers. Since breastfeeding is protective against SIDS, it could be argued that co-sleeping can actually increase safety for breastfeeding families! 

Emotional health

In the West, we value independence in our children. However, there is some evidence that co-sleeping (while perhaps delaying “independence” in the short term) actually leads to children being more confident in social settings and more able to problem-solve in the long term. (Keller and Goldberg, 2004) I think this makes sense from a neuroscience perspective. We know that babies that have their needs met promptly, have better emotional health. Babies spend a considerable amount of time sleeping. If this sleep happens in contact with an adult, where their needs are met promptly, and they feel more secure when they sleep, it makes sense that their brains would develop more healthy pathways as a result. 

Man and woman asleep in bed. A baby is lying next to the woman.
Image taken from the BASIS co-sleeping image archive. Click on the photo to see more images of safe co-sleeping.

When should you NOT co-sleep?

We generally recommend that you don’t co-sleep if you can’t maintain a safe co-sleeping environment (see below). In addition, you should NOT co-sleep with your baby if: 

Your baby is premature, is a low birthweight (under 2.5 kg) or is unwell

Prematurity and low birthweight increase the risk of SIDS, when in an adult bed. There does seem to be an increased risk of SIDS when babies that normally don’t co-sleep are brought into a parent’s bed when they are unwell. Of course, it’s hard to say whether the risk of SIDS is higher because the baby is unwell to begin with, or whether the co-sleeping increases the risk. 

You smoke (or anyone else in bed with the baby smokes)

Smoking poses serious health risks for infants. It is crucial that both parents refrain from smoking, ideally as soon as they become pregnant, but especially when practicing co-sleeping. Smoke exposure significantly increases the risk of SIDS.

You have taken alcohol or sedating medication

If you have taken any substance that may inhibit your alertness, then it’s important that you don’t co-sleep. 

What about breastfeeding? Can you co-sleep if you aren’t breastfeeding? 

The Lullaby Trust does not state that you should be breastfeeding if you want to co-sleep. BASIS suggests that breastfeeding leads to safer co-sleeping practices. This may be because breastfeeding mothers instinctively place their baby at breast height rather than at face level. There may also be a degree of synchronicity and awareness that arises from breastfeeding and co-sleeping – “breastsleeping” that I mentioned earlier). The theory being that breastfeeding mothers are more aware of their babies in bed. 

I’m not convinced to be honest and I don’t think breastfeeding is a deal breaker for safe co-sleeping. While anecdotal, my first baby was bottlefed and I always faced her in bed. With my second, who was breastfed, I actually woke up frequently with my back turned to him!! I think it is possible to teach safe positioning to all mothers, irrespective of whether they are breastfeeding or not. I think it is possible for bottlefeeding mums to be aware of their baby in bed with them, much like breastfeeding mums. 

NEVER, ever sleep on a sofa with your baby

Unfortunately, often parents get up out of bed because they are scared of co-sleeping, and then fall asleep with their baby on a sofa or a chair. This increases the risk of SIDS exponentially and is so much more dangerous than bed-sharing. Ironically, some of the messaging we give parents about co-sleeping can actually increase the risk unintentionally. 

Image taken from the BASIS co-sleeping image archive. Click on the photo to see more examples of safe co-sleeping.

Conditions for safe co-sleeping

In the UK, we use the Lullaby Trust guidance for safe sleep. I’ve looked at these recommendations below, and discussed the special considerations for co-sleeping. Where relevant, I’ve also used guidance from BASIS, which is also a great resource on safe sleep, including safe co-sleeping. These guidelines include: 

Baby sleeps on their back

Always place your baby to sleep on their back. This position significantly reduces the risk of sudden infant death syndrome (SIDS). If your baby feeds on their side in bed, then it’s important that they are rolled back onto their back once they are finished feeding. 

Firm mattress

Ensure that the mattress is firm and adequately fitted to the bed frame. A sagging or overly soft mattress increases the risk of accidental suffocation or entrapment. Avoid waterbeds, sofas, or excessively cushioned surfaces. Mattress toppers or memory foam should also be avoided. Think about gaps around the edge if your bed is pushed up against a wall, in case a baby could roll into that gap. For babies that are mobile and active in bed, it may be safer to move the mattress onto the floor and use it as a “floor bed”, to reduce the risk of your baby/toddler rolling off the bed! 

No pillows or bedding close to the baby

Keep the sleeping surface clear of pillows, duvets, heavy blankets, or stuffed animals that can obstruct the baby’s breathing or cause overheating. Instead, dress the baby in appropriate clothing and use lightweight blankets if necessary. Babies that co-sleep should sleep at breast height, rather than up on a pillow facing their mother. You can use baby sleeping bags rather than blankets to keep your baby warm. If you are cold, then you could try layering a couple of long sleeved tops, or wearing a cardigan to bed. Fleecy pajamas can work too! 

No pets or older siblings in bed with the baby

It’s important that there is a responsible adult sleeping with the baby. Some parents will co-sleep with a baby and toddler. Sometimes this is unavoidable, and in this scenario, the parent should sleep between the baby and toddler. 

Baby should never sleep alone in an adult bed 

This is fairly self-explanatory. Remember that adult beds are designed for adults, and it’s your responsibility to make sure that your baby is safe and supervised. In any case, for the first six months all sleep should be supervised and in the same room as you anyway. 

Ensure the room is at a comfortable temperature, between 16-20°C

This may not be possible in the UK, especially in Summer, as we tend not to use air conditioning. If you cannot maintain the room temperature between 16-20°C, then it may be appropriate for your baby to sleep wearing only a nappy in bed!  

So, should you co-sleep?

It’s probably fair to say, that based on mammalian behaviour, and cultural practices around the world and through history, co-sleeping is the norm for us as a species and separate sleep is the unusual practice. 

I believe that co-sleeping can be safe. I think that the research does suggest that provided there are no risk factors, co-sleeping is as safe as a baby sleeping in a crib on their own. However, I cannot recommend a blanket approach to co-sleeping. Some families can co-sleep safely. Others cannot. It is up to each individual family to assess the risks for them. You may want to use this risk assessment tool from BASIS to help you make up your mind. 

What if co-sleeping really doesn't work for you?

Co-sleeping works for a lot of families, whether through choice, or desperation. I do work with a lot of families for whom co-sleeping is no longer sustainable. This may be either because parents are struggling with a physical issue which makes co-sleeping painful, or perhaps because they actually get less sleep with their baby in bed with them. It may also be that they can’t adhere to all the safe sleep guidance.

If this is you, make sure you read my next blog which is all about moving away from co-sleeping. Alternatively, I carry out a lot of sleep consultations where parents need to move away from co-sleeping, so I can also give you personalised advice and support. You can find out more here, or book a free introductory call with me here


Ball, H (2007), Research Overview: Bed-sharing and Co-sleeping, accessed 14/07/2023 

Keller, M, Goldberg, W (2004) Co-sleeping: help or hindrance for young children’s independence?,, accessed 11/07/2023

McKenna, J (2020) Safe Infant Sleep, Platypus Media, Washington DC

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