
Blood Transfusion from Ever-Pregnant Females Associated with Mortality in Males - dtparr
https://jamanetwork.com/journals/jama/article-abstract/2657377
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nkrumm
This is an interesting study, and I highly encourage everyone to also read the
accompanying editorial, which raises some important methodological
shortcomings. See here:
[https://jamanetwork.com/journals/jama/fullarticle/2657356](https://jamanetwork.com/journals/jama/fullarticle/2657356)

The reason this study was done because there has been a very well replicated
association between the plasma (not red cells) donated from previously
pregnant women and the risk of TRALI, a very rare but deadly transfusion
reaction. After this association was made clear, blood banks no longer collect
plasma from previously pregnant ("ever pregnant") women, and the overall rate
of TRALI has dramatically dropped (from about 35 fatalities in the US per year
to ~15).

Source: MD/lab medicine resident

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wnissen
Do you have any insight into why, when they were looking at men vs. two types
of women, 88% of the blood donors were men? Seems like you would want at least
50% women.

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salad77
I don't think an ethics committee would approve of exposing a study group to a
known or suspected higher risk of death without significant safeguards.

Using a small sample exposed to the suspected risk and the vast majority not
exposed sounds like responsible ethics.

It is not stated, but there should also have been additional safeguards and
monitoring. It is normal for studies to be terminated early if they are found
to expose participants to either too much danger or if the study group is
found to be significantly advantaged (in which case, for example, the whole
group is given the beneficial treatment instead of just the small study
group).

50% may sound 'fair' or 'equal', but this is about researching ways of saving
life, some social notion of fairness or gender equality is not relevant and,
if this study is correct, could have caused excessive death. Is it worth
people being killed to get the gender balance into the shape you prefer?

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ThatGeoGuy
> Is it worth people being killed to get the gender balance into the shape you
> prefer?

This is obviously a tough question to answer, and maybe the answer here is no.
Further, I wouldn't say "worth people being killed" as much as I'd say it's
"worth risking people dying". Obviously this is context sensitive and is
different for each treatment and study.

Despite this, as the devils advocate, you could say that given that men and
women can respond to different treatments in a range of ways, the ideal
distribution would be diverse enough to accommodate for those differences,
which would provide a better statistical subset and by extension producing
"better" data. Same caveats apply, where you mentioned "too much danger" and
if the study is "significantly advantaged". In short, it could be less about
fairness (equity) or equality and more about collecting a broader or more
diverse range of data.

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downrightmike
Correct answer is always no. No one should be knowingly killed or endangered
to suit a biased view.

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Mz
As a guess, a follow up study should maybe consider that chimerism is a
factor. IIRC, a woman remains a chimera for about 27 (or 27.5?) years after
giving birth (ie her blood contains DNA from the child she carried). So, you
could look at data for female blood donors whose last pregnancy was more than
27 years ago and those whose last pregnancy was less than 27 years ago.

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rabboRubble
I wonder if that data is even captured in the donation process?

Aren’t donations pooled? Can’t imagine this would leave very many pools
without a single ever-pregnant donor.

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dogma1138
As far as I know only Plasma doses are pooled because of the washing process.

Pooling is also done for blood testing they’ll pool samples from a batch
together and if the pooled sample comes back positive they’ll discard the
entire batch of part of it if subpooling was used.

Red blood cells doses come from a single donor.

I’m not sure about platelets.

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autokad
Not completely surprised.

not exactly the same, but in rats young blood makes older rats more healthy
and the younger ones less so due to stem cells:
[https://www.nytimes.com/2014/05/05/science/young-blood-
may-h...](https://www.nytimes.com/2014/05/05/science/young-blood-may-hold-key-
to-reversing-aging.html)

(making the assumption more pregnancies = higher age)

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Kevguy
If it was related to higher age, wouldn't blood donations from older males
also be problematic?

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autokad
yeah, but as far as I saw they didn't distinguish age at all. they did men,
ever pregnant women, and non ever pregnant women.

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emh68
Has anyone ever studied this stuff before? You think they'd have noticed that
if true...

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crb002
Should be able to detect some rogue protien.

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upper98
[https://en.wikipedia.org/wiki/Data_dredging](https://en.wikipedia.org/wiki/Data_dredging)

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okket
To be fair, the authors are open about the shortcomings:

> further research is needed to replicate these findings, determine their
> significance, and define the underlying mechanism.

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rcthompson
I don't know that the level of significance reported in the paper even
justifies further research.

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dragonwriter
> To be fair, this is more or less "boiler-plate text" added at the end of
> every research paper

There is usually something discussing future research needs, but it's not
always oriented toward “replicate and determine significance”.

Though something very much like the note on my this paper is common, for good
reason, on papers reporting a novel, borderline significant association with
no clear mechanism.

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sxates
So there really is something about the blood of virgins?

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BDGC
I hate to break it to you, but never pregnant != virgin

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Zarathust
Never pregnant is a superset of virgin. According to most

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rabboRubble
Welllll....take a gold star lesbian. She is technically a virgin if you
measure virginity by penis-in-vagina sex. She still can become pregnant
through artificial insemination. Plus the Virgin Mary!

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Mz
Don't forget Schmi Skywalker. ;-)

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jwilk
Please use the original title.

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dtparr
I tried to, but the original title "Association of Blood Transfusion From
Female Donors With and Without a History of Pregnancy With Mortality Among
Male and Female Transfusion Recipients" was approximately double the maximum
length allowed by HN. I actually spent about 10 minutes trying to figure out
the smallest change that was still grammatically correct and fit the 80 char
limit while being as accurate as possible.

That being said, if you have an improved version that fits, I'd be happy to
support that.

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dang
Likewise. That was a particularly hard title to crack.

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jwilk
<title> says: "Association of Female-Donor Blood Transfusion and Recpient
Mortality"

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dang
Probably better. I almost used it but thought people would complain about it
burying the lede.

