My wife and I recently welcomed a wonderful baby girl into our family and as I was sitting
there in the delivery room, I had the idea of making a video about the placenta.
I mean, how often do you get the chance to make a video and teach people about the amazing
placenta?
So, after having a discussion with the delivery staff and reassuring them that I wasn't going
to be eating it considering it was covered in meconium or baby poop, they were happy
to let me have it and that way I can show and teach you today.
So, put your forks away and let's do this.
[Intro]
So, first off, I want to let you know that today's video is going to be slightly
different than videos you're used to seeing from us and that's for a couple of different
reasons.
The first is that the placenta doesn't come from any of the cadavers here in the lab,
instead, it comes from my wife and our newborn daughter.
So, she was born last week in the delivery room, I looked to the OB and asked her if
I could take the placenta here to the lab in order to make this very video.
So, that also means that it's unembalmed or unfixed.
So, there is going to be blood.
Now, I've done everything I possibly can to prepare this placenta to make it the least
bloody it possibly can be, the least graphic it possibly can be but if that's something
that you just don't want to see, I completely understand.
I'm not going to get mad at you.
This may not be the video for you.
So, with that said though, we're going to be focusing a lot just - really just on the
anatomy of the placenta and mainly the macroscopic or gross anatomy.
In future videos, we plan on doing a whole wide variety of content around embryology,
fetal development, the stages of labor, just what happens to mom during pregnancy.
There's so many cool things to talk about and there's a good chance that we may even
try to preserve this placenta so we can use it to make future videos.
So, with all that said, let's go ahead and take a look at the placenta.
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So, this right here is what's called the fetal surface of the placenta and we can also see
the umbilical cord.
Now, as I lift it up, you are going to see - let's see if I can actually get this into
a good view in the camera - that there are going to be a lot of blood vessels.
Now, so when I say the fetal side, that means this is the side the fetus was looking at,
interacting with and this is actually fetal tissue.
So, this is actually same tissue that came from my daughter during development but attached
to it is, like I mentioned, going to be the umbilical cord.
Now, the umbilical cord is actually a pretty simple structure.
They're going to be two arteries in one vein that are then going to be encased in what's
called Wharton's Jelly which is basically just a mucoid mucus type connective tissue,
has a lot of sugars inside of it but this is going to send blood vessels to and from
the fetus and you can see those blood vessels branching out on this fetal surface.
This is actually called the Chorionic plate although there is a membrane on top of this
which is called The Amnion.
So what would happen is there would actually - and I had to cut this away because it just
would have made the video undoable, but there was an amniotic sack.
So, we've all probably heard of the amniotic sac but the amnion is just a layer that would
be on top of this fetal surface and then what it would do is it would actually come into
the umbilical cord and then branch out.
So, you can kind of picture there would be like this sack that the fetus would be inside
of and then the umbilicus, the umbilical cord would connect to the umbilicus of the fetus.
So, I had to remove that amniotic sack but all of those blood vessels are going to and
from the fetus as well as mom.
So, as I flip this over, this is going to look a little graphic.
So, I'll see if I can do the best I can here.
This is the Maternal Surface of the placenta, except - you know, I almost hesitate same
Maternal Surface because there really isn't a surface to begin with.
You have to understand that the placenta is a combination of both the fetus and mom's
tissues.
So, every single month that a woman is ovulating, when she has her menstrual cycle, there's
an inner lining to the uterus called the endometrium and that is going to get thickened by a hormone
called Progesterone and then when it becomes thickened, it gets named the Decidua.
The Decidua is going to have a lot of sugars and lipids and fats inside of it and it's
actually going to have the embryo embed into it and then grow.
So, what happened was as the fetus grew and grew the placenta, right?
You had this matching.
So, you had the fetal surface growing on one side into that maternal surface, into the
decidua and so, when this was born, right?
Because the placenta is actually born, right?
This is that third stage of labor.
What will happen is once the fetus is born and the blood is going to stop being supplied,
right?
Going back to that - to the placenta.
What will happen is it'll start to detach a little bit and then the uterus is also contracting
and so, the the whole placenta is going to start breaking away and you're also going
to have you know, the delivery staff and that OB pulling on the actual cord as gently as
they can but from what I've seen it doesn't look to be very comfortable at all, and they
are going to then bring it out.
And so, this is the after birth.
And so, what's going to come - so what will happen is since it's breaking away, you're
essentially looking at a wound here, right?
This is a wound because this would have been merged with the decidua of or the endometrium
of the uterus but since it broke away, you're now seeing that maternal surface.
Now, I should also say the decidua continues to leave the uterus over the next days and
weeks ahead, right?
There's going to be a lot of bleeding as the uterus is continuing contracting, going down
and everything's getting smaller.
Now, what's really cool about these is what you're looking at.
You're looking to see like these mounds.
Let's see if I can actually do this.
I'm going to pull up my probe.
So if you look here, this is really difficult for me to do but there's almost like these
little mounds, almost like mountains and valleys.
You can definitely see it right around here.
Those mountain areas, those are called Cotyledons and then inside - then you're going to also
have this sulk eye kind of like dipping down but the Cotyledons are going to be where the
maternal blood is going to meet the fetal circulation, so as we turn it back over.
So, all these blood vessels are going on - throughout the surface of the placenta and then it's
going to start burrowing its way down.
So, what you have is mom's blood supply is going to be coming from the uterus and it's
going to go into this space called the Intervillous Space.
Here it's going to empty blood into pretty much just a pool but it's going to be separated
and completely separate I should mention from the fetus.
This is how you can actually have different blood supplies between our blood types between
mom and fetus say like A positive or A negative.
Now that creates a whole host of other issues that we can talk in future videos but just
to understand, maternal and fetal blood supply, they should never actually interact with each
other and if they do you have a very serious problem.
But what will happen is all of these blood vessels here will then branch out into little
trees and will come in close proximity with that pool of blood and so, this is where,
and this is the overall function of the placenta is that this is where nutrient, oxygen and
waste exchange can occur, right?
Because the fetus isn't going to be able to breathe inside of the womb like breathe oxygen
in the air, so what happens is oxygen will come in carbon dioxide will go out, right?
You're going to have nutrients like vitamins and some minerals and you're going to have
all sorts of like sugars and you know, lipids and proteins - everything that the baby is
going to need to grow is going to go in there and then you're also going to have waste exchange
that is also going to leave outside of here.
Really really cool.
All of that is going to be happening - I'm gonna turn this back around - in those cotyledons,
right?
Those which are just going to be - you can see here.
You can see a giant one right there.
Now, when I say the Maternal Surface, this is actually more properly called the Basal
Plate and then the other side, instead of saying Fetal Surface this should actually
more be called the Chorionic Plate but if you remember me saying, there was actually
a membrane on top of it and that membrane is called the amneon.
But another function of the placenta besides going to be facilitating nutrient exchange
and oxygen and carbon dioxide exchange is also an endocrine function.
You see, every single month what happens is progesterone levels will drop and the decidua
will then slough off and in fact that's essentially what decidua means is to slough off.
So, you obviously don't want that to happen when you have a growing fetus and a growing
baby so what will happen is you have something inside of the ovary called Corpus Luteum which
is going to help sustain that but what I want you to understand is that the placenta, another
one of its function is to produce hormones to basically just tell mom's body "We're pregnant,
we're still pregnant.
Don't slough off the desidua, let's keep all of this going".
But there's plenty of other hormones such as growth hormone that are going to be secreted
from the placenta.
So, I just want you to know that the placenta is an absolutely incredible organ and that's
because in my estimation, in my personal view, it is a part of the most amazing incredible
and beautiful process in all of biology and that is the growth of the human fetus.
That's again why I want to do multiple videos on you know, just embryological development,
fetal development, stages of labor - all of it because it's such an incredible process.
And for me as someone who never has to physically go through it but instead I get to observe
it, you know, I get to kind of have this very intellectual with it so I got to nerd out
with it.
I may not be able to empathize but I can definitely nerd out and just find it to be intellectually
fascinating but I really hope you enjoyed today's video on the placenta.
Again, this is so cool and hopefully the next time you see this, it will be preserved and
then we can have it - we can even have some more really fascinating and interesting discussions
but thanks for watching everybody and I will see you in the next video.