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This is an MRI of the abdomen in a patient

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with a normal third trimester pregnancy.

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This is an axial, T2-weighted image

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of the abdomen, and we don't have to

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scroll very far down before the gravid

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uterus starts to come into view.

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We can really see the progression and the

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change that's happened both within the

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fetus and the uterus between the first

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and second trimesters up to this point.

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What I'd like to point out is that anteriorly

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here is again that T2 heterogeneous layer of

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myometrium that's wrapping all the way around.

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We get a beautiful look at the third trimester

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placenta, which should be homogeneous in its

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signal intensity and uniform in its thickness.

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As we can see on the sagittal, this is

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an anteriorly located placenta, and we

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have a qualitatively normal amniotic

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fluid volume with a fetus that's

0:53

in cephalic presentation, head down.

0:56

You'll notice that the center

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of these images is a bit dark.

0:59

That artifact on MRI is called

1:01

dielectric effect and can happen when the

1:04

patient's abdomen is large, which often

1:06

happens in the context of pregnancy.

1:09

So this is a normal third trimester pregnancy.

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And what I just want to point out here

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is, again, the dramatic increase in the

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size of the uterus, the displacement

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of the bowel and abdominal viscera. And

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at this point in pregnancy, it can be

1:25

really challenging to find the ovaries.

1:27

We don't see them on this set

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of images for this patient.