If you’ve ever had a parent-to-be show you an ultrasound picture of the baby, you know determining what you’re looking at, let alone detecting a family resemblance, isn’t always easy! But ultrasound pictures can be amazingly clear and useful — if you know what you’re looking for.
Following are some of the items that doctors and sonographers try to pick out on ultrasound to find out whether the baby is growing and developing well.
Measurement of crown-rump length
The crown-rump length (CRL) is the distance from the top of the fetus’s head (crown) to the buttocks (rump) during the first trimester. It’s the most precise sonographic measurement your practitioner can use to estimate gestational age. The other things that you can see in this image are a measurement of the nuchal translucency (NT) and the nasal bone (NB).
The face
Many people think the view of the fetus, taken during the second trimester, is sort of ghoulish. Some say that the baby looks like ET. But keep in mind that it’s not a traditional photograph of the baby’s face. The ultrasound beam passes through the fetus wherever it’s directed and renders a picture of a “section” of the inside of the baby, not the surface.
The spine
The spine is one area that even most novices at ultrasound can easily find. Take a look at it here. In the second trimester, imaging the entire spine is important in order to rule out neural tube defects.
The heart
The image is the classic four-chamber view of the fetal heart that your practitioner looks for on ultrasound in the second trimester. You can clearly see two atria and two ventricles. A normal four-chamber view rules out the most major heart abnormalities. During an actual ultrasound, you can see the heart beating and the valves moving.
The hands
In the second trimester, counting fetal fingers and toes is a challenge because the fetus moves constantly. But this image captures them all.
The foot
Although you can’t predict shoe size yet, you can see five toes on the foot here, caught on ultrasound in the second trimester.
The fetal profile
Here, you can see a fetus in the second trimester lying on her back. You can clearly see her forehead, nose, lips, and chin.
Three-dimensional image
In contrast to the other images that are two-dimensional, this image is a different type of ultrasound that renders a picture of what the baby actually looks like. This image shows the baby’s face with the arm in front of part of the mouth.
3-D ultrasound is one of the newest technologies available and provides amazing pictures, but hasn’t replaced traditional two-dimensional scanning yet. 3-D images have limited use for routine evaluation of the baby at present.
It’s a boy!
As you can see, getting a very clear view of the developing penis is often possible.
It’s a girl!
The figure shows an easily recognizable image of the labia.