From what your baby should wear, to what they should eat, to how you should talk to them, bathe them, or change them.

And one of the biggest things that everyone says to avoid is co-sleeping, or letting the baby sleep in the same bed as their parents.

But the science says that it may not be as outright hazardous as we thought.

And it may even have some benefits.

In 1994, the National Institutes of Health in the US launched the Back-to-Sleep campaign, which they now call Safe-to-Sleep.

The campaign originally recommended that babies should only be placed to sleep on their backs.

But as pediatricians did more research, the NIH started adding more recommendations to their list, including that no one should be co-sleeping with their babies ever.

Co-sleeping can have slightly different definitions based on who you're talking to, but for this video, we just mean any time you have a baby sharing the same sleeping surface as a non-baby person.

Some researchers do also differentiate co-sleeping and bed-sharing, since co-sleeping could include sleeping right next to each other, but on different things, like when a baby is right next to the big bed but in its own crib.

Whereas bed-sharing specifically means sleeping on the same surface.

While it is somewhat common in countries around the world, in the US, co-sleeping is, to put it mildly, strongly discouraged.

And the recommendations against co-sleeping aren't just from people who want their personal space.

They came from studies that linked the practice of co-sleeping with SIDS, or Sudden Infant Death Syndrome.

As the name suggests, SIDS is the blanket term used for babies under a year old dying suddenly.

It's a really sad fact of life that sometimes babies die with no clear explanation for what happened.

It's been hypothesized that some SIDS cases could have medical causes, like undiagnosed neurological conditions.

But the whole point is that we just don't always know why SIDS happens, which makes it unexpected and, of course, very sad and tragic.

In the past, suffocation-related deaths often got lumped in under that SIDS category, too.

And in some cases, a SIDS death can even be caused by a little of both.

For instance, some babies have trouble waking from deep sleep, or have cardiac issues, or have some neurological issue that makes it hard for them to detect when there's too much carbon dioxide in their blood.

So, if a baby that's already vulnerable to dangerously low oxygen levels then also gets wrapped up in their bedding, you get the idea.

Because of that, some researchers now use the term SUID instead of just SIDS.

SUID, or Sudden Unexpected Infant Deaths, is the umbrella term that covers SIDS, but also includes all of the infant deaths for which we know the cause, but are still unexpected.

So that includes the unexplained reasons, but also the ones due to stuff like suffocation, where we know what happened, it just wasn't anticipated at all.

And it's not a small number.

Stats from 2020 say that of the 3,400 SUID deaths in the US, about a quarter were from suffocation.

But some of the talk around the risks of co-sleeping still frames it as being about SIDS, not suffocation, which are two different things.

This is kind of a lot to unpack, so we're going to do our best to do that for you.

Anyway, back to the 90s.

Research started during that period found that a big risk factor for SIDS was the sleeping environment.

For example, babies who slept on their tummies, or on a soft surface, or shared a bed with their parents had an increased risk of death.

One study found that over an 8-year period, as many as 515 babies died from suffocation or strangulation after sleeping on adult beds, daybeds, or waterbeds.

Around 100 of those were directly caused by the person who was sleeping in the same bed, usually when they accidentally rolled onto or up against the baby.

Other risks are that they could get trapped in a gap between cushions, their face could get covered by a pillow or blanket, or they could roll over face down.

And unlike adults, babies literally can't get themselves out of those dangerous situations since they can't really, like, move a whole lot.

But there are a lot of other behaviors that we know are linked with increased risk of suffocation that still apply whether or not a baby is in the same bed as their parents.

Things like loose bedding, soft sleep surfaces, pillows, and basically anything that has the potential to get all wrapped up around a baby's face.

Which is why the other safe sleep recommendations say to keep sheets and pillows away from the baby and put them on a single, firm surface to mitigate those suffocation risks.

And the thing is, some of those early co-sleeping studies didn't take into account those other factors that lead to suffocation and weigh them all accordingly.

A 2001 study that looked at infant mortality figures from the 90s in Alaska found that of 40 co-sleeping-related deaths, only one happened without any other risk factors present, meaning only one death was actually SIDS.

To be clear, some co-sleeping safety risks include things involving the parents, too.

For instance, having parents who smoke, are intoxicated when going to bed, or who are getting less than four hours of continuous sleep a night.

They're all things that increase the riskiness of co-sleeping.

But other studies have found that co-sleeping is only linked with infant death if there are other risk factors present, too.

Which means that at least some of the fears around co-sleeping may be based on an incomplete picture of what causes the danger.

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On the flip side, some research suggests that there are potential benefits to co-sleeping, too.

First off, it's comfy.

For babies, it's thought that being close to their parents let them hear and feel that heartbeat, smell the oh-so-cuddly scent, and just generally know that their people are right nearby.

In fact, some researchers think that co-sleeping may be important on an evolutionary level, and that there are benefits to a baby's psychological and social development that come from sleeping in the same space as other people.

Around the world, there are plenty of cultures that associate sharing a bed with your baby and emotional well-being for everybody involved.

And the rate of SIDS in countries where co-sleeping is more common varies a lot.

SIDS rates are around 0.1 deaths per 1,000 babies in Japan and Sweden, 0.8 in New Zealand, and even as low as 0.04 in Italy.

Another big reason parents choose to co-sleep is to help with breastfeeding, with parents reporting that it is easier to feed when the baby is in the same bed.

And breastfeeding has a bunch of benefits, too, including reducing the overall risk of SIDS.

One review of 11 studies related to bed sharing and breastfeeding came up with a whole list of upsides.

For starters, there was some evidence that families who co-slept had longer durations of breastfeeding throughout the night than families who didn't, although this effect wasn't found in all cases.

They also found that, on average, moms who breastfed and co-slept got more sleep than bottle-feeding moms, which sounds ideal.

And studies done in the UK, where co-sleeping is more common, found that families who co-slept in the hospital were more likely to start and continue breastfeeding when they got home.

And finally, both parents and babies might wake up more easily when co-sleeping, which might be better than it sounds.

The idea here is that if anything goes wrong, both the parents and the baby are more likely to wake up and fix the problem before it's too late.

So where does this leave us?

Well, there's still a big stigma around co-sleeping.

Scientific American reported that some hospitals in the US will not discharge people after they give birth unless they sign forms promising not to bed share.

But some other international ministries of health and pediatric associations are starting to offer guidance on how to bed share safely, instead of just saying never do it and leaving it there.

Safer bed sharing guidance matters, since a lot of people end up bed sharing even when they didn't plan to, because that's what works for their baby.

So it can be better to tell people how to do it safely, rather than just saying do not ever do it.

The guidance includes not having pillows or blankets near the baby, moving the mattress to the floor to reduce fall risks, placing the baby on their back, and ensuring that the sleep environment is smoke-free.

Of course, where you sleep matters, too.

These guidelines apply to people sharing a firm mattress with their baby, not sleeping in an armchair or on a couch.

There are also a whole bunch of other guidelines and recommendations that we don't have time to get into, but you can easily google them on your own.

The big takeaway here is that there is no one perfect way for babies to sleep.

But there are safe and unsafe ways to do all of the sleep methods, whether that's a bassinet, a crib, or in the big bed.

We hope that this helps all you parents out there sleep a little easier at night, whether your baby is next to you in bed or not.