
Caesarean babies have different gut bacteria, microbiome study finds - uxhacker
https://www.theguardian.com/society/2019/sep/18/caesarean-babies-have-different-gut-bacteria-microbiome-study-finds
======
giarc
This has been known for quite a while, basically passing through the non
sterile vaginal canal vs the sterile (or close to it) abdominal wall yields
differences. This has lead to some questionable practices such as "vaginal
seeding" whereby new moms will swab their vagina and then seed their babies
shortly after birth (usually through placing the gauze in babies mouth or
around their face). This comes up not infrequently at the hospital I work at.
I think much of it stems from Facebook rather than actual discussions with
their OB.

~~~
tssva
The article addresses this practice and states that the bacteria found in
babies born vaginally differs from the bacteria found in the vaginal canal
this further calling into question this practice. The bacteria instead seems
to come from the mother's gut.

~~~
DanBC
Specifically, it comes from faecal matter that she expels during the birth.

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certmd
My younger brothers are identical twins, one born vaginally and the other 20
min later via C-section. I've always said they'd be good data for these type
of studies.

Anecdotally, they don't really have big differences regarding allergies or
autoimmune disorders. Although growing up I always complained one stunk up the
bathroom worse than the other.

~~~
toolslive
Any idea how frequent this (the first naturally, the second via C-section) is
?

~~~
robbiep
Increasingly in developed countries twin births are caesars; the risk profile
of twin births often necessitates this for patient safety.

When a normal vaginal delivery is possible (ie first twin cephalic) generally
the second will follow. My partner (obgyn Resident ) says she has had 2 twin
births where the first was vaginal and the second Caesar, out of roughly a
couple hundred

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umeshunni
This has been hypothesised for a while and is listed in many pregnancy books.
There are also hypothesis linking the difference in gut flora to other long
term outcomes (obesity, autism etc) in adults.

Reference:

J. Neu and J. Rushing, “Cesarean Versus Vaginal Delivery: Long-Term Infant
Outcomes and the Hygiene Hypothesis,” Clinics in Perinatology 38, no. 2
(2011): 321–331.

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erikrothoff
My twin brother was born by caesarean. He gets asthma attacks from allergies
that I don’t have. I’ve wondered for a while what effect a faecal transplant
could have...

~~~
chapium
This is something that his doctor should be concerned with.

~~~
sxv
The idea that there is some doctor who will employ the latest and greatest of
medical research to take care of me is at odds, to say the least, with my
experience in the healthcare system.

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mhermher
I was under the impression that this has been pretty well established for a
while.

~~~
scaryclam
Came here to see if I was going crazy or if others had also heard of this
before.

Is this about new findings? Or just a regurgitated set of findings to get into
the press? The article isn't clear as far as I can see.

~~~
iamsmooney
Here is a link to the study the article references published today:
[https://www.nature.com/articles/s41586-019-1560-1](https://www.nature.com/articles/s41586-019-1560-1)

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primroot
> “In many cases, a caesarean is a life-saving procedure and can be the right
> choice for a woman and her baby,”

And in other cases it is a way to make life easier for medical staff?

Here in Panama, babies are disproportionately born through C-section in
privately run hospitals.

Update: While I can't cite any stats for Panama, there is an article [0] that
says

"The rates can be even higher in private clinics. For example, in Brazil,
80-90 percent of births in private clinics are now C-sections, compared with
about 30-40 percent of births in public hospitals."

[0]
[https://www.npr.org/sections/goatsandsoda/2018/10/12/6561984...](https://www.npr.org/sections/goatsandsoda/2018/10/12/656198429/rate-
of-c-sections-is-rising-at-an-alarming-rate)

~~~
s3graham
"To posh to push", was also a saying a generation ago.

~~~
clydethefrog
In Dutch the C-section is called the "King's cut".

~~~
afraca
Sorry for nitpicking: "emperor's cut"

~~~
Smithalicious
Named after emperor Caesar, just like the word "caesarian".

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AstralStorm
I wonder, does this relationship hold at 1 month old? 1 year?

Any decent longitudinal studies of C-section babies from elective sections
removing the health based ones?

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pinky1417
Having a c-section might not be the underlying cause of the problem. Doctors
carry out c-sections when a vaginal birth would create complications for the
mother or the child. I.E. the mother or child was already "sicker" prior to
the c-section.

I'd love to see a randomized control trial for this. To do it ethically, the
trial could be designed like the CRASH trials. In those trials, doctors
received patients with head injury and administered a placebo or
corticosteroids. Since it was unclear whether corticosteroids helped or hurt,
it was ethical for doctors to randomize patients. For births, only situations
where it's 50/50 between a c-section and vaginal birth would qualify. Perhaps
it's too small a subset to be workable or perhaps it's never 50/50, but that
type of trial would provide much stronger evidence for this intriguing idea.

On a personal note, I was a c-section baby and seem OK!

~~~
fiatjaf
> the mother or child was already "sicker" prior to the c-section

That is your illusion.

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donclark
TL DR: C-section babies pick up more hospital bacteria than those born
vaginally, research shows. The findings could explain the higher prevalence of
asthma, allergies and other immune conditions in babies born by caesarean. By
six to nine months, the differences between the two groups had levelled out.
But scientists think that the initial exposure to bacteria at the moment of
birth could be a “thermostat” moment for the immune system, defining its
sensitivity and which strains of bacteria trigger a response.

~~~
DanBC
Please don't tldr if you're going to do it this poorly.

The new bit of this story is that the vaginal canal isn't adding anything to
the microflora of the baby, and that the source is in fact fecal matter from
the mother during birth.

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refurb
The biggest question that surround all this microbiome discussion is - does
the difference even matter?

Note that you can significantly alter your gut microbiome simply by changes to
your diet.

Right now the link between the microbiome and allergies is tenuous at best.

~~~
mcbuilder
My understanding is that yes environment makes a huge difference in your
biome, however there may be strains of bacteria, for example, that you would
only get from your mother. Maybe something she picked up playing in the dirt
in a different country, or maybe something from her mother.

Whether it makes a difference really depends on the individual. Personally I
think it's better to get the gut bacteria that you can from your mother near
the time of birth, but that's me.

~~~
refurb
If you were to test the microbiome of a family, you’d find they are very
similar. Humans living in close quarters exchange biomes readily (oral - fecal
transmission).

I’m certainly not arguing there is no impact of the microbiome on disease, but
right now the data is far to early to say anything conclusively.

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aszantu
I was depressed for half my life, I read on gut microbiome about 5 years
ago(swapping the gut microbiome of mices changes their character) but didn't
put it together until I switched my diet to meat only. Any kind of sugar seems
to trigger depression for me, that sadly means that I can't eat plants. And
current push for plant based diets worries me a lot. I was a C-Section baby.

~~~
jaynetics
Eating only meat is a serious health risk.

There are other sources of protein, and many vegetables that go very well with
a low carb diet.

~~~
rhinoceraptor
> Eating only meat is a serious health risk

[citation needed]

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mcantelon
Gut bacteria IIRC effect personality/mood as well as other things.

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trhway
the mother probably gets antibiotics before caesarean. Does that antibiotic
make it into the baby? That would mean that beside not getting the good
vaginal mix of bacteria (that mix among other benefits seems to be able to
control candida yeast growth which is a big deal on its own), the bacteria set
that the baby already possesses gets hit by the antibiotic, a double whammy of
sort.

~~~
robbiep
A Caesar mother does get a stat of antibiotics before opening. In crash
caesars this would barely have time to distribute; normal operating procedure
calls for the dose to occur 30 min to 1 hr before skin incision though.

You have a bit of a misunderstanding here - a baby does not have a microbiome
in the womb - it is a sterile environment

~~~
trhway
>You have a bit of a misunderstanding here - a baby does not have a microbiome
in the womb - it is a sterile environment

no.
[https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4350424/](https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4350424/)

"The first, and most important, contribution to the genesis of the microbiome
is vertical transmission of maternal microbiota. Colonization of mucosa in the
digestive, respiratory, urogenital tracts, as well as the skin begins at, or
perhaps even before, the time of birth when a newborn is exposed to a mother’s
microbiota. It was previously thought that the in utero environment was
largely sterile and that a fetus was not colonized with bacteria until the
time of birth. Recent studies suggest the presence of a microbiome within the
placenta as well as fetal meconium, suggesting that the colonization process
begins well before delivery. "

And my point is that the "most important, contribution to the genesis of the
microbiome" probably gets hit with the antibiotics given for C-section.

~~~
robbiep
Thanks. This is new knowledge since I was at medical school.

The paper you link however is not at all convincing.

A better paper here:
[https://www.frontiersin.org/articles/10.3389/fmicb.2019.0112...](https://www.frontiersin.org/articles/10.3389/fmicb.2019.01124/full)

Does a better job of explaining things. Interestingly the species isolated are
highly homogenous -
[https://www.frontiersin.org/files/Articles/454989/fmicb-10-0...](https://www.frontiersin.org/files/Articles/454989/fmicb-10-01124-HTML/image_m/fmicb-10-01124-g001.jpg)

Most samples had only a single species isolated from meconium; Controlling for
sources of contamination it looks like out of the sample of 43 there were
several that would meet the classification of a sterile environment.

So, I was wrong; but so are you

~~~
trhway
I'm not insisting on specific source of bacteria. I mentioned it only as
illustrative detail/example, and it only distracted (who knew that here would
be a medical professional for whom getting such details right is naturally
important - the same way like it is very distracting for coders when movies
get computers related details wrong :) from the main point that baby coming
out of C-section may have antibiotics in him/her which would screw with
whatever gut microbiome "priming" scenario pre-/post- delivery he/she would be
going through.

~~~
robbiep
I take your point but it’s not binary - in the sense that I have strong doubts
that the MIC (Minimum inhibitory concentration) of antibiotics would touch
much of a colonisation in a neonate should it be present.

Having a single dose of abx in an adult doesn’t kill everything; the intent of
a pre-surgical dose of abx is because evidence shows it significantly reduces
post op infections; and the antibiotic used is active primarily against gram
positives (cephazolin 1-2g) whereas _Pelomonas puraquae_ is a gram negative
anerobic rod and more than likely not going to be touched, even if the MIC is
reached (and my experience of obstetric theatres is the antibiotic usually
(80% of the time) goes in only minutes before skin incision.

So; a couple of things:

\- presuming no contamination in the study, the primary coloniser of neonates
appears to be a gm -ve rod

\- antibiotics given for caesars are active against gm +ves /aerobes

So while there may be a mechanism, it’s not highly plausible in light of the
other known mechanisms affecting Caesar births vs natural (ie bacterial
microbiome pickup during traversal of the birth canal) about which there is
significant evidence regarding immune priming

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unixhero
This is old news.

~~~
uxhacker
I thought the same, but No, as the original hypothesis was the bacteria came
from the vaginia, but this study shows it comes from gut. It maybe because
during delivery women often have anal fissures.

~~~
DoingIsLearning
I am not an obstetrician but I am pretty sure that fecal transfer is far more
likely because of acccidental pooping while 'pushing' instead of anal
tearing/fissures.

~~~
unixhero
Oh God. How did I get here.

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Syzygies
Many of us Caesarian babies didn't get "vaginal seeding" at birth, but have
been trying to catch up ever since.

~~~
irrational
You joke, and are being downvoted, but I had never ever thought about
cunnilingus affecting ones gut biome. Is that ridiculous or even possible?

~~~
Syzygies
It certainly affects gut biome, personal observation and what I've read.
Michael Douglas also believes this caused his cancer.

It's a cliche that the kids from the rich side of town, who didn't put dirt in
their mouths growing up, are the ones who get mono in college. Farm kids are
healthiest; our immune systems need regular work they can manage.

~~~
amelius
> Farm kids are healthiest

Why can't we just buy some farm dirt in pill form?

~~~
refurb
Coronado Biosciences tried to treat Crohn's disease using hookworm eggs.
Basically give the patient a bunch of eggs, the hook worms hatch, cause an
immune response, then die (as they can’t live in humans).

Clinical trial showed no impact at all on the disease.

~~~
alanh
I think you mean to say they can't, but… they can
[https://www.cdc.gov/parasites/hookworm/gen_info/faqs.html](https://www.cdc.gov/parasites/hookworm/gen_info/faqs.html)

~~~
refurb
I did mean “can’t”.

Coronado used porcine (pig) hookworm eggs that’s can’t complete a reproductive
cycle in humans.

