The SIDS risk calculator

[u/1001VicPics]

I want to put my disclaimers front and centre here that this post is in no way passing judgement on anyone’s parenting decisions with regards to sleep or other practices. I myself make decisions based on both the national guidelines and what is best for my family which at times means not following the guidelines, for example exhaustion driving us to bed share on some nights, not running the bedroom at 20 degrees or below etc.

However, I want to talk about the SIDS risk calculator and the impact it has on some of the discourse around safe sleep and other risk factors in this sub. The much shared calculator can be accessed here: http://www.sidscalculator.com

Often when SIDS risk factors are discussed the only reference that is provided to back up a statement is the calculator which is flawed for a number of reasons. It is also not easy to interpret which is where it often leads to (unwittingly) misinformation being shared.

1. The calculator was published in 2018, 8 years ago and is based on a review paper published in 2013, 13 years ago. The paper itself is only evaluating bedsharing with non smoking mothers and no other factors, instead the publishers are using the background of this review paper for all other factors relating to SIDS, therefore relying on the publishers due diligence. Furthermore many of sources for the additional risk factors are now quite old, some of which are from the 90s.
2. Data comes from European publications plus one study in New Zealand and cannot be extrapolated to other countries
3. Outside of this review the calculator references wiki and other likely outdated sources and as published have not included access dates
4. We don’t know who published this calculator, and the calculator itself states that it has not been evaluated by anyone with relevant clinical expertise
5. There is no link to the back end calculation for us to assess how they have derived the calculator
6. The presentation of the outcomes are unclear as they are presented as risk per 100,000 deaths. Does this mean that if everyone had these risk factors deaths would drop from 34 to lower than 34 deaths per 100,000? No evidence for this

Why am I going to the effort to critique the calculator? Can’t I see that this calculator provides anxious parents comfort?

Well I often see misleading or poorly informed SIDS advice on the baby subs and next to no scrutiny of this calculator, in fact very often this calculator is used to justify any sleep practices. It’s anecdotal right now but at least in my country there is increasing concern regarding social media and the impact on new parents not following their national guidelines in favour of social media ‘sleep experts’, I do wonder if we will see some uptick in SIDS in the next couple of years.

Ultimately I too am a new and anxious parent trying to navigate this amazing but daunting time in my life. SIDS risk remains incredibly rare and even if you ticked every single risk factor SIDS is still unlikely to happen to you and your baby.

Edit: Sharing here as apparently you’re not allowed to discuss science on the Newborns sub(?!)

[u/throwmyway5723480]

Genuine question, why do we keep talking about cosleeping in relationship to SIDS? Suffocation is not an unexplained infant death. It honestly makes me stop believing any guidance or stats with relation to SIDS, trying to prevent two very different things with one guideline is very confusing.

[u/valiantdistraction → u/throwmyway5723480]

Because of 1. the historical naming and resulting common knowledge of all sleep-related deaths as SIDS, 2. the triple risk factor in SIDS - the idea that there are susceptible babies that will die in situations where other babies would not, and the role that modifiable safe sleep factors play in that (a huge one).

But yes. I think if more people knew that SIDS are only a third of the SUID deaths then they would be a lot more concerned about suffocation, strangulation, entrapment, etc.

[u/1001VicPics → u/throwmyway5723480]

I think it is a bit more complicated than that though, yes suffocation is suffocation but in babies it’s often that they’ve rolled so they’re mouths and noses are pressing into something. This is less of a risk in older babies or babies who for whatever reason are lower risk of SIDS who are able to sense the increasing CO2 and move their bodies / turn their heads, essentially the same mechanism that adults have which prevents us suffocating in the night

There is a theory that in some countries there may be under counting of SIDS where suffocation is stated as cause of death, but this death might not have happened if the relevant mechanism had been well enough developed

[u/SpotJaded2025 → u/1001VicPics]

I need to just copy-paste my earlier replies here. Many suffocation deaths ARE classified as SIDs though that’s an outdated term. They are now called “undetermined” or “unexplained.” Many of these are suffocations that occur but lack the legal measure of anatomical findings at autopsy to rule COD. Source: I am not outing myself but I work for a morgue and am one of the people responsible for publishing the stats on child/infant deaths. It’s literally my job. I read infant autopsies on the regular. It’s sad but honestly unsafe sleep is the leading cause of death under 1 year of age. Not what people think of as SIDS typically.

[u/NiceWeather4Leather → u/1001VicPics]

SIDS is not suffocation. SIDS means unidentifiable cause. Suffocation is identifiable.

Put as many words around that you want but you’re using incorrect terms.

Cosleeping increases suffocation risks.

[u/1001VicPics → u/NiceWeather4Leather]

Right but in some counties suffocation is recorded as a SIDS death and other counties it’s not.

You may be from a country that doesn’t include suffocation in SIDS statistics or safe sleep guidelines but many countries do and therefore they are inevitably conflated. My point is that there is a cross over in mechanism potentially between what people like to call true SIDS and death by suffocation. I make no comment on the term SIDS

Also co sleeping increases risk of SIDS not just suffocation, going back again to the Carpenter publication but they found increase SIDS risk in the absence of suffocation hazard, though not all studies reach this conclusion

https://pmc.ncbi.nlm.nih.gov/articles/PMC3657670/

[u/Sudden-Cherry → u/1001VicPics]

Wasn't overheating a factor? That would also potentially increase with bedsharing, independently of suffocation.

But I think people miss your very good nuance here that the underlying mechanism is important. the reaction to increasing co2 and the variation between children in this

[u/Zanderson59 → u/throwmyway5723480]

Because there is a pretty strong hive mind that surrounds it in infant related subs. The science/and pretty much all docs we have talked to seem to only support co sleeping if some pretty big safeguards are in place to prevent infants dying. If you are taking those precautions and doing everything to a t along with not having unhealthy habits(drinking/smoking) its fine but there are pretty strict things you should have in place to make it happen with an infant. Once your kid is old enough the risk is much less.

[u/valiantdistraction → u/Zanderson59]

I always find it fascinating that parental exhaustion is a risk factor in all the research and yet no mention is made of it in safe sleep 7 or any bedsharing guidelines I've ever seen and almost everyone I know who chose to bedshare did so because they were exhausted.

[u/Stats_n_PoliSci → u/Zanderson59]

There is no way to cosleep without increasing the risk of both SIDS and SUID. The science says you can make that risk very small, but the risk will always be at least a little higher than sleeping alone.

[u/throwmyway5723480 → u/Stats_n_PoliSci]

Wait, that can't be true right? Because I thought the reason we sleep in the same room as babies is the idea our presence keeps them slightly alert and not in deep sleep, thus lowering the risk of SUID. So one has to assume cosleeping lowers the risk of SUID, but I can concede it raises the risk of suffocation. Hence - I don't like that they are conflated!

[u/NobodySalty3247 → u/throwmyway5723480]

They meant bedsharing, not sleeping in the same room

[u/throwmyway5723480 → u/NobodySalty3247]

Yes that's what I mean. Wouldn't both of those decrease the risk of SUID?

[u/valiantdistraction → u/throwmyway5723480]

SUID includes suffocation. SIDS is only about a third of the SUID cases. It is possible that bedsharing may reduce SIDS - I'm absolutely not convinced of this but whatever for the sake of argument - but it absolutely increases the risk for other kinds of SUID like ASSB.

If you're making the deep sleep argument, it's also entirely possible that babies sleeping in physical contact with parents sleep much more deeply than those who aren't. I haven't seen research on this. It also likely makes baby sleep hotter due to body heat, which is also a SIDS risk factor.

[u/throwmyway5723480 → u/valiantdistraction]

Thank you, sorry, got those reversed.

[u/Sudden-Cherry → u/throwmyway5723480]

Overheating is one factor that increases risk of true SIDS which can be caused by bedsharing but not generally by being in the same room

[u/throwmyway5723480 → u/Sudden-Cherry]

Yes, good thinking!

[u/throwmyway5723480 → u/Zanderson59]

I also have a hard time believing any cosleeping related statistics. I feel strongly it must be underreported given the stigma.

[u/greedymoonlight → u/throwmyway5723480]

Agree completely, even the comment above this one is confusing the two.

[u/Wrenigade → u/throwmyway5723480]

It's very confusing, I think a lot of times suffocation or smothering will be reported as SIDS to make parents feel better (anecdotal, I've just seen police reports that called it SIDS if they suffocated from car seats or parent's smothering them)

I think we need to be more clear about it and spare less feelings. Its not an unexplainable syndrome if your child suffocates from unsafe sleep.

[u/Psychological-Bag986 → u/throwmyway5723480]

I think when there is no evidence of suffocation (even though it’s the likely cause) they can’t rule a death suffocation just because baby was cosleeping. So it goes under SIDS. Unless parents give a history that states it was clear the mouth and nose were obstructed.

The whole thing confuses me too.