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Course: Health and medicine > Unit 12
Lesson 4: Pregnancy complicationsUterine inversion
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Want to join the conversation?
- how long is the umbilical cord?(1 vote)
- about 50cm
The umbilical cord connects a baby in the womb to its mother. It runs from an opening in your baby's stomach to the placenta in the womb. The average cord is about 50cm (20 inches) long.(6 votes)
- What is the placenta made of?(2 votes)
- Here's what I got from google:
The placenta begins to develop upon implantation of the blastocyst into the maternal endometrium. The outer layer of the blastocyst becomes the trophoblast, which forms the outer layer of the placenta. This outer layer is divided into two further layers: the underlying cytotrophoblast layer and the overlying syncytiotrophoblast layer. The syncytiotrophoblast is a multinucleated continuous cell layer that covers the surface of the placenta. It forms as a result of differentiation and fusion of the underlying cytotrophoblast cells, a process that continues throughout placental development. The syncytiotrophoblast (otherwise known as syncytium), thereby contributes to the barrier function of the placenta.
Hope that helps!(1 vote)
Video transcript
- It's funny. I remember in the very first delivery I ever attended, right
after the baby was delivered and the umbilical cord was cut, I started to unscrub and remove my gloves. And then I heard someone yell
out, "Hey, where you going? "We still have to deliver the placenta." So they were right. The
delivery of the baby is followed by the delivery of the placenta, which usually occurs
within five to 15 minutes. But it shouldn't take
longer than 30 minutes. After 30 minutes, you start to think that something might be wrong. And, as you're standing
there, with your hand gently, very gently, holding on
to the umbilical cord, there are four key signs
that you look out for that signal that the
placenta is separating from the wall of the uterus. So let's talk about what
those four signs are. The first is that the
umbilical cord lengthens. And that makes sense. The umbilical cord is
attached to the placenta. And if the placenta is
detaching from the uterus, more of the umbilical cord
should appear in front of you. So that's the first sign,
that the umbilical cord, the umbilical cord,
umbilical cord lengthens. The umbilical cord lengthens. The second sign is a gush of blood. The second sign that the
placenta is separating from the wall of the
uterus is a gush of blood. Which, if you can visualize it, the placenta is shearing away from the underlying endometrium. And that shear rips apart blood vessels, causing the bleeding to occur. And all of this is
happening spontaneously. How? Well, after the baby is delivered, the uterus shrinks in size, because the uterus is muscle, after all. So it has the ability to stretch
and shrink really rapidly. But the placenta isn't a muscle. It doesn't change shape as ready. So as the uterus shrinks
and kind of retracts away, the blood vessels in the placenta tear. So that accounts for the bleeding. Now, to understand the
third and the fourth signs of placental separation,
you have to understand what I think is the
absolute most amazing thing about the uterus and the placenta, and that is the structure with which the muscle fibers of
the uterus are arranged. So, the muscle fibers of
the uterus are arranged in a kind of criss-cross fashion around the blood vessels. So, here you have the
muscle fibers of the uterus, and they're arranged kind
of in a criss-cross fashion, kind of like, kind of like a lattice around the blood vessels. So when the uterus contracts, it squeezes on these blood
vessels, which have now been sheared and ruptured,
to stop the bleeding. Without this feature,
the mom would probably die of a hemorrhage from the
separation of the placenta. But the uterus contracting down on these blood vessels stops the bleeding. And the third and fourth signs are related to that contraction of the uterus. So you feel, the third
sign is that you feel, the uterus feels firm and globular. So you can actually feel
that it's firming up and that it's more globular,
globular in shape, right? And you also, the fourth sign is that you're able to feel
the uterus rising up to the anterior abdominal wall. So you actually feel
the uterus contracting and sort of pushing up, or rising up, to the anterior abdominal wall. So why am I going into so
much detail about these signs? Well, it's because we look
for them, we wait for them. Because when they all occur, we know that the placenta is coming and we can sort of help the process out. But sometimes a practitioner
can put too much pressure on the umbilical cord too early, that is, when the placenta is still
firmly attached to the uterus. And that can lead to
inversion of the uterus, or the uterus sort of turning inside out and coming out through the vagina. And that kind of looks like this. The uterus is kind of turned inside out because you pulled on the
umbilical cord too hardly. And the best way to
prevent this from happening is to wait til all four
signs, not two, not three, but all four signs of
placental separation occur before you put any traction
on the umbilical cord. But if the uterine inversion does occur, the very first step is to
try to reposition the uterus back into its normal position. And that can be pretty challenging because the uterus is in a
contracted position, right? It's contracted, and that
makes it harder to manipulate. So that's why I will often start off by using uterine relaxing agents, so, uterine relaxation
agents to first, sort of, relax the uterus, make
it softer, more pliable. And then, after the uterus is relaxed, the practitioner will
then place the uterus back into its normal position. And after the uterus is placed back into its normal position,
we'll usually follow this with a uterine contracting agent, or what's called a
uterotonic agent, right? So "utero" meaning "uterus," "tonic" meaning "tone,"
"contraction," right? So uterotonic agent. And the uterotonic agent
helps to limit the bleeding, because, again, when the
uterus contracts down, it squeezes off those blood vessels that are running through it. And it also helps, the
uterotonic agent also helps to prevent reinversion of the uterus. So that's why we use it. Now, another thing, this also very important to keep in mind, is that uterine inversion
can be accompanied by a lot of bleeding. So volume replacement, sort
of blood volume replacement, is a very central part of treatment. So before we finish off this topic, I wanna mention a couple of things that put a woman at risk
for uterine inversion. I already mentioned that
putting too much traction on the umbilical cord is
one huge, major risk factor. Another thing that makes uterine inversion a lot more likely is having a placenta that's too firmly attached to the uterus. And you can imagine, the
placenta's too firmly attached to the uterus,
and that makes you, that would probably make a person pull on the umbilical
cord too hardly, right? And that condition, where the placenta is attached too firmly to the uterus, is called placenta, it's called placenta, placenta accrea, right? Or very firmly adherent placenta. And you can also probably
imagine that having a floppy uterus makes it easier to invert. So use of uterine relaxing agents can also increase the risk of inversion. Okay. So that's uterine
inversion in a nutshell, a condition that teaches us to be, or reminds us to be, patient
and to remember that, even though the umbilical
cord may look like a rope, we're not playing tug-of-war
with the placenta.