What Is An Anatomy Ultrasound?

When you reach the 20-week mark in your pregnancy, you’ll likely undergo an anatomy ultrasound. This important exam checks for fetal anomalies, assesses your baby’s size and weight, and tracks growth to ensure everything is on the right path.

By now, your baby might weigh around 11 ounces and measure approximately 10 inches in length when fully extended. Remarkably, your little one already has fingerprints, small arms and legs, and often well-formed genitalia. You might notice yourself starting to "show" more prominently. From this point until your due date, the rate of growth will pick up significantly.

What Will The Technician Be Looking For?
 

The technician or doctor will be assessing whether your baby is developing at the expected rate. By this time, the skeleton should be starting to harden, and the baby’s sex might be visible—though sometimes, the baby may be positioned in such a way that the gender isn’t easily seen.

What Will Happen During the Ultrasound?

Once you’re called into the ultrasound room, you’ll lie down on an examination table. A full bladder may cause some discomfort, but rest assured, the ultrasound itself is painless and can be quite enjoyable. The technician or doctor will apply a warm gel to your abdomen and use a small paddle to conduct the scan. During this process, they’ll check various parts of your baby, including:

• Face
• Brain (ventricles, choroid plexus, mid-brain, posterior fossa, cerebellum, cisterna magna, with measurements of anterior and posterior horns of lateral ventricles)
• Skull (shape, integrity, BPD and HC measurements)
• Neck (nuchal fold thickness)
• Spine
• Heart (rate, rhythm, 4-chamber views, outflow tract)
• Thorax (shape, lungs, diaphragm)
• Abdomen (stomach, kidneys, liver, bladder, wall, umbilicus, cord, abdominal circumference AC)
• Limbs (femur, tibia, fibula, humerus, radius, ulna, hands, feet femur length FL)
• Genitals (gender, abnormalities)
• Cervix (length and opening)
• Amniotic fluid
• Placenta position and any anomalies
• Mother’s adnexae to check for abnormalities of the ovaries and fallopian tubes.

The measurements taken during this ultrasound help calculate the gestational age of your baby based on an average size for this stage of pregnancy. Keep in mind, these calculations have a margin of error of about 2-3 weeks. Early ultrasounds tend to be more accurate in dating the pregnancy. If any concerns come up, further testing might be recommended.

Pictures and Fun!

You might also get a keepsake from this special moment: many technicians will print images of your baby’s face, and occasionally the sex organs, for you to treasure. The quality of these pictures can vary depending on whether the scan is 2D, 3D, or even 4D. Advanced technology can create a 3D image that adds an extra layer of detail.

Some machines may be equipped to record videos. If you’re interested in having a video recording of the ultrasound, be sure to ask your technician beforehand if this is an option.

The anatomy ultrasound around the 20th week can be both a joyous and a slightly nerve-wracking experience. Some parents are eager to find out their baby’s gender, while others are simply thrilled to see their little one’s face. It’s all part of the incredible journey you’re on, and this moment adds a new layer of connection to the life growing inside you.