No link between acetaminophen use during pregnancy and adverse birth outcomes | Hacker News Reader

No link between acetaminophen use during pregnancy and adverse birth outcomes

sph.unc.edu

77 pointsgeox56 comments

This paper says there are no adverse effects to the mother, but it does not mention possible adverse effects to the child beyond "birth health" and does not address the recent controversy about a possible link to autism.

Why would it need to? There is no medical controversy.

There’s only a weak and now discounted statistical association that was seized upon by two disgraceful anti-science politicians to create a political controversy.

I can't figure it out. What is the actual reason they knowingly LIED about it?

Some personal grievance against Tylenol brand?

More graft from a competitor?

Appease their conspiracy loving dumbass base?

Destroy the scientific reputation of the US?

Trump is actually that fucking stupid?

All of the above?

The administration promised they'd find a cause by September 2025. I guess that was the best they had at that point?

https://www.cbsnews.com/news/rfk-jr-cause-of-autism-research...

They promised to find a reason. My best guess is that they picked a generic drug that is only a painkiller to blame in order to blunt any possible lawsuit. But it’s equally possible that RFK Hr, who is weird, fully evil and profoundly dangerous, actually believes it.

This is just how authoritarian governments operate. It’s not some Machiavellian set of dominos. It’s more of a test of loyalty to The Administration than anything else.

I don’t think they’re lying. They probably honestly think they are correct.

They actively reject the values of intellectualism, critical thinking, and expert consensus. They instead embrace empiricism, loyalty, and the great man theory.

It’s a recipe for severe Dunning-Kruger.

> empiricism, loyalty, and the great man theory.

One of those things is not like the others. Presumably you had another word in mind.

I did in fact mean empiricism... but it is empiricism while rejecting intellectualism. They believe their personal observation and judgement are superior.

I am not sure, but the claim was that there is some date based correlation when this drug started being used, and rise of some health issues kids...

It’s hard to ignore a link when the n is this large. A 15% greater chance of getting autism is very significant.

A 2024 study of nearly 2.5 million children initially found:

* Autism by age 10: 1.53% with prenatal exposure versus 1.33% without * ADHD: 2.87% versus 2.46%

https://jamanetwork.com/journals/jama/fullarticle/2817406

This is the study you are referring to. I will leave it to others to judge your comment.

> Acetaminophen use during pregnancy was not associated with children’s risk of autism, ADHD, or intellectual disability in sibling control analysis. This suggests that associations observed in other models may have been attributable to familial confounding.

To spell it out: the study’s point (sorry, “Conclusions and Relevance”) is to explain away the very data GP cites?

It's a shame this became a high-profile political issue, because there is a real unanswered medical question there, as even that study acknowledges ("associations observed in other models", including that study itself outside of the sibling control analysis).

Also: "However, a 2021 consensus statement by an international group of scientists and clinicians recommended that pregnant individuals “forego [acetaminophen] unless its use is medically indicated,” among other precautionary actions, due to potential risk of developmental disorders such as autism and attention-deficit/hyperactivity disorder (ADHD)."

http://dx.doi.org/10.1038/s41574-021-00553-7

>Why would it need to?

Because that is what everyone (I mean, not if you are pharma) is interested in...

Perhaps you believe there is no medical controversy, but there is a legal one:

https://reason.com/volokh/2026/07/20/the-second-circuits-pro...

It's very difficult and boring to follow a newborn until at least their 16th year of age, when mental development and IQ stabilise. It would be interesting if we new about the effects of eg. breast feeding, co-sleeping, parenting types and even mother's drugs like anti epileptics during pregnancy. There are some long term studies that follow newborns and they tell a lot, although they swim in a confounding ocean.

And yet I still see MAHA defenders even on HN.

Some of us appreciate the "Eat fucking food, and do some exercise" part of it. The rest of it is a big meh. Not like I was looking to Rachel Levine as a paradigm either.

"Eat healthy food and exercise" has been recommendation #1 for ages. The idea that RFK and his friends are somehow novel in this public communication is bizarre.

RFK walked the talk. The previous inhabitant was... and I'll try to be polite... easy to dismiss when they said it.

I don't know if advertising a diet of primarily beef and sauerkraut is walking the walk. His opinion of what "healthy food" is is based in vibes and conspiracy rather than scientific rigor.

> on how early a child is born or a child’s weight at birth

These are not particularly important. The concerns are autism and ADHD.

Also don’t equate that MAHA crap with disagreement on this topic. I’m as anti MAGA as it gets but this study doesn’t do anything to assuage people’s primary concerns about this.

Now do the study in mutated (MTHR, MTHFR, COMT, others, some combination of them) sample populations.

Why?

Because those mutations change detox efficiencies.

Not sure I understand the question!

clean chit!

is this just lying with statistics?

surely some abuse of the drug could lead to adverse reactions?

are they just arguing for specific doses to not have negative effects? (that would be true of a lot of things we consider harmful)

How could you think that anyone would argue that arbitrary doses of any medication are safe? Drinking too much water will kill you.

Just for the sake of honest balance, with minimal commentary and no opinions:

Acetaminophen and dementia correlation:

https://pmc.ncbi.nlm.nih.gov/articles/PMC2877629/

https://www.sciencedirect.com/science/article/abs/pii/S01638...

Note that it's also hard on the liver. A lot fatalities due to taking after hangovers, etc: https://www.medicalnewstoday.com/articles/322813 So if you insist, maybe take some NAC.

But apparently, Ibuprofen helps counter the dementia risk:

https://www.aan.com/PressRoom/home/PressRelease/624

I am not not asserting any clever marketing here. I am merely citing public information. Noting all the above, I am confident it's perfectly safe for children and fetuses, and if posing any risk at all, applies strictly to full grown adults. No doubts about child safety have been expressed here.

The first paper shows no evidence of any effect from Tylenol...? But yeah seems like lots of support for the ibuprofen protective effect, interestingly.

If you do start munching on advil; note there are rumors, by medical researchers, case reports, and more, that if you dig beneath the shiny surface to find, do show a lot of compelling data for GI damage, heart risk and other serious side-effects. And depending on how fair one wants to be with 'evidence' -- almost all wording describing NSAIDs as "protective", uses easy-to-miss but distinct qualifiers such as "potential" and other such vague 'maybe'-equivalents that alone have been used to suppress and dismiss many other...potential medicines. Sometimes, conclusive just means inspired. And sometimes ambiguity means certainty, depending on levels of inspiration involved.

Of course, one might pause for a moment to consider just how potential the alluded benefits really are with ibuprofen, and ask why doctors aren't recommending it for mental health, or as a general health product. But that might point to the peculiar fact that there is substantially more evidence suggesting risk over health benefits, and the benefits really depend on what one wants to see. There is a reason it's not marketed as a health product, but with the way it's framed, it should be, nu? I mean, potential benefits sells a lot of snake oil and lowfat yogurt. Why not advil and acetaminophen?

And by similar logic used to dismiss acetaminophen here as a health risk, eg because there's no link with autism/ADHD it's safe; why not apply the same logic to opiates? We could just say opiates do not directly cause, eg , parkinsons, or AIDS, therefore it's safe for babies. Myself, I never correlated acetaminophen with autism/ADHD, but I know it has more side-effects than listen on the bottle.

Yeah I work in clinical trials so I'm very comfortable with all the caveats the need to be applied to correlative studies like these.

Which also answers your other question of why doctors don't recommend it: we don't actually know that it does this.

As for the rest of the ramble, you (or I) definitely don't know hardly anything that hasn't been established in clinical trials. Certainly can't just vibes-based assess a label and its completeness. It's really, really hard to know things.

The precise wording as far as safety is: "we have no substantive or high-quality evidence that the drug is unsafe."

Because we couldn't possibly modify

"we have no substantive or high-quality evidence that the drug is unsafe." - (damn all the research showing it is)

--to

"we have no substantive or high-quality evidence that the drug is safe." - (damn all the research suggesting it isn't)

Well, that's as good a green light for an ad campaign as one could ask for. "we don't actually know that it does this." ain't never stopped a motivated pharmaceutical rep before. You have my official endorsement for feeding advil and acetaminophen to all. And protection from dementia is just what America needs. !Win / !Win

Maybe restless leg and depression too! And don't tell me fetuses don't get depressed there in that dark womb. We know damn well they get restless.

Drugs are approved for the specific uses based on extremely high-quality evidence. That evidence balances the benefits against the detectable downsides/costs/side-effects. Those downsides are also on the label.

That's almost entirely generated by the highest quality evidence generation system we could possibly have, which is RCTs. And no, pharma reps actually aren't allowed to encourage (or even talk about) off-label uses of drugs.

I get the sense that you don't know much about this space.

>highest quality evidence generation system we could possibly have, which is RCTs.

The "best we have" does not mean it is good enough for the task at hand. Just saying.

Basically what I am saying is that qualifying something by saying "best we have", does not justify its using on its own..

1. I didn't say "the best we have." I said the best we could possibly have. There is no form of evidence generation, real or hypothetical, greater than the randomized controlled trial.

2. That doesn't necessarily make it always "sufficiently good evidence", but the beauty of statistics is we actually can know – quite precisely – whether a given evidence generation method gives us sufficient certainty. When an RCT is used as evidence for approval, it is not "well you did an RCT so I suppose it's fine." Approvals actually are not dependent whatsoever on the evidence generation method. The only thing that matters is whether you prove – to sufficient statistical certainty – the claims you are making. It's very hard to do this without RCTs (again being the greatest evidence generation form that could exist), which is why they tend to be the default. But you can run an RCT that fails to produce certainty, and your drug application will be denied. You can also get approval based on a non-RCT (but again it's hard to do because statistics).

We've had this discussion before and the crux of the issue is that you do not understand statistics while the people who design, run, and evaluate clinical trials do. I highly recommend taking a statistics course or four.

>There is no form of evidence generation, real or hypothetical, greater than the randomized controlled trial.

Wrong. You are lying by omission.

Randomization and controlling are essential. But the version of RCT that we currently employ have problems with control and evaluation. If you have a flaw in control or evaluation, then the whole thing becomes flawed.

So the idea of RCT is good, but we are limited by our ability to control and evaluate.So there can be a better version of RCTs that we currently employ, but with precise control and evaluation.

> but the beauty of statistics is we actually can know

The beauty of statistics is also that it is quite easy to hide falsehoods behind statistics.

There Are Three Kinds of Lies: Lies, Damned Lies, and Statistics

(I am not even going into the fraud problem, which is what we have discussed before, which turned out to be quite useless)

The liver toxicity is well known, and overdose is not uncommon.

A better policy fix would be to remove it from multi-drug products. Require it always be the only active ingredient.

> overdose is not uncommon

Anecdotally, I hear about it far more in Internet comments like the parent than elsewhere. How common is it?

Poison center stats, annual, acetaminophen...

https://jamanetwork.com/journals/jamanetworkopen/fullarticle...

Emergency department visits ~56,000

https://pubmed.ncbi.nlm.nih.gov/16294364/

Hospitalizations ~26,000

https://pubmed.ncbi.nlm.nih.gov/16294364/

Deaths ~500 deaths/year

https://pubmed.ncbi.nlm.nih.gov/16294364/

Also, direct from FDA, for those promoting its use with alcohol: "Be aware that severe liver damage may occur if you have three or more alcoholic drinks per day while using acetaminophen." One can infer that stressing the liver prior, then again with tylenol, might be unwise. But by all means, headaches suck. I understand.

Also:

https://www.niaaa.nih.gov/health-professionals-communities/c...

But do not worry. The FDA only specifies that to qualify as risk, requires 'daily' intake of 'three or more drinks'. That is 'daily'. Therefore, it is, if you manage to survive binge drinking several cases of beer and your drinking pattern is null for day1-6, but n amount on day7, perfectly safe to take acetaminophen at will. The documentation does not refute this, therefore it is safe. Only daily drinks, three or more. Binge ok. Only official documentation good true. Inference bad false.

I stand corrected by ctoa!

And to the noble clinical researcher in the house (estearum), I much respec your authorituh. No corruption or monetary influence has ever affected the medical or research field. This I do not dispute. As a chartered researcher, you are an impervious and pure and good person. And honest too. Pharmaceutical industry applies here as well; beyond reproach -- if you're in, you're pure. The notion that they have financial incentives is schizophrenic and despicably paranoid. Anyone who thinks otherwise can have a $200 epipen stuffed in their eye, for free.

I also humbly rescind all my own experience and research. A single I "don't know much" sense from an illustrious professional medical champion was the evidence I needed to retire. Farewell and I shall never think nor speak again. All that cherry pickin really wore me out ;(

And for all:

ScienceDirect S0163834323001317 - A 2023 piece ("Association of regular use of ibuprofen and paracetamol, genetic susceptibility, and new-onset dementia in the older population") that found regular paracetamol use, but not ibuprofen, associated with higher risk of new-onset all-cause dementia, AD, and vascular dementia, independent of genetic risk. But ignore that. Acetaminophen is uncontested by good people. This = bad people https://www.sciencedirect.com/science/article/abs/pii/S01638...

*Mess due to comment throttling.

Didn’t read your links but wonder how they deal with selection bias. People at increased risk for stroke or bleeding disorders, even if just self perceived risk, are told to favor acetaminophen because of the risk inherent in ibuprofen and naproxen sodium.

The Pubmed articles are from 20 years ago. The 2023 JAMA article has some qualified information:

"In 2021, US poison centers received more than 80 000 cases involving an acetaminophen product.1 The National Electronic Injury Surveillance System estimated that 78 414 emergency department (ED) visits occurred annually in the US from January 1, 2006, through December 31, 2007, for overdoses of acetaminophen-containing products.2 In Canada, approximately 4500 hospitalizations occur each year because of acetaminophen overdose.3"

It doesn't tell us risk. Acetaminophen is very widely used, potentially the most widely used drug. I'm not sure what these numbers represent in terms of risk.

With cost of healthcare, inflation, unemployment, housing crises, wars and whatever else folks have to be thrilled about these days, I am willing to risk assuming alcohol consumption is not going to be on a permanent downward trend. And pain management is far more challenging now than it was 20 years ago, many having no other option beyond NSAIDs for serious problems. That's not hard data, but it is me being quite confident that whatever the numbers were then, won't remain all time highs if they ever were or aspired to be.

Also, I do not work too hard around here, especially with all the corporate aligned types that patrol the area. Folks can do their own research, while they can, before history is rewritten by LLMs and the new internet. Yeah, a lot of articles and papers are getting more difficult to find. And institutional capture is well underway with AI. Newer generations think because they can't find something, it never existed. This is HN, with a karma economy and high price on honesty. I am just leaving occasional marks in the gray zones.

What those numbers really don't get into:

~80% of acetaminophen poisoning cases severe enough to end in hospital are intentional suicide attempts.

Those patients also have better outcomes though: family members know what happened, they get them to a hospital, they can take N-acetylcysteine as a timely antidote.

In the unintentional poisoning group, ~90% is from multi-day accumulation, they don't realize they've been poisoning themselves. They have a much higher rate of acute liver failure and death.

https://doi.org/10.1186/cc1475 https://doi.org/10.1016/j.cld.2013.07.001 https://doi.org/10.1097/mcg.0b013e31818a3854

Regarding the unintentional overdoses:

"There are two distinct clinical syndromes described in literature. One is the 'garden variety', wherein the patients ingested large amounts of acetaminophen with a suicidal intent .... The other pattern is seen in chronic alcoholics who ingest smaller amounts of acetaminophen in an attempt to relieve pain ...."

"The causes of chronic pain in the accidental overdose group were toothache, chronic backache, or headache."

https://link.springer.com/article/10.1186/cc1475

Yes, and those alcoholics also exactly fit the multi-day accumulation pattern. These aren't people taking one day of Tylenol after a bender for a hangover. The pattern is people with an impaired ability to process acetaminophen (alcoholics) taking multiple days of doses they can't handle (their daily safe dose is about 1/2 of normal) for chronic pain (like chronic back pain).

"A lot fatalities due to taking after hangovers" no, that's not how acetaminophen fatalities happen. In fact, the article you cited specifically mentions "there is no scientific evidence that people with AUD (alcohol use disorder) who take the recommended dose of acetaminophen increase their risk of liver damage."

Fatalities happen basically from: product stacking combination medicines people don't realize contain acetaminophen and/or multi-day accumulation exceeding max daily limit over multiple days.

Chronic drinkers have impaired acetaminophen processing so they can't handle otherwise safe doses, but fatalities still typically occur in multi-day accumulation scenarios. Their safe daily max is ~half that of a non drinker.

The effects of one round of acute drinking don't impair the liver in the same way. People are not dropping dead because they took a normal dose of acetaminophen for a hangover. Not that I'm recommending you start doing it, but it is a myth.

> Fatalities happen basically from: product stacking combination medicines people don't realize contain acetaminophen and/or multi-day accumulation exceeding max daily limit over multiple days.

I find it obnoxious that NyQuil has taken over as the default brand people grab for cough syrup, for that reason. It has acetaminophen, while Robitussin or such have the other active ingredients without that risk.

The typical person doesn't read and understand active ingredients, and it's lucky if they even check dosage instructions.

I absolutely think we should ban acetaminophen in otc combo meds. There was a big drop in hospitalizations when they dropped the max allowed dose in prescription drugs like Vicodin, there's no reason these otc things like NyQuil need to exist at all.

I think it's supposed to be an anti-abuse thing for commonly abused drugs.

Maybe I'm crazy, but I don't think killing people is an improvement.

This article is about "how early a child is born or a child’s weight at birth". I don't know why we're talking about other possible negatives of Acetaminophen. Seems off-topic to me.

So a guy who beckons to "Keep HN weird." and has a history of non-strict adherence to subject titles with his/her own comments implies I must not challenge a title that claims "no adverse birth outcomes" from acetaminophen with closely related acetaminophen concerns and possible counter data? And that is some kind of special, golden? double standard?

But truly, if I am the only rascal here on HN, deviating slightly from the subject title, I will gather the tinder. Let's burn me with haste!

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