Each week is important during a pregnancy, as the baby continues to grow and change day by day. But when it comes to 18 to 20 weeks, expecting mothers go in for an appointment they are most likely a little anxious about. It’s time for a full anatomy ultrasound scan.

It’s the chance for the physician to really be able to see how the baby is developing in the womb. We chatted with Dr. Brooke Chalk, at Novant Health Coastal OB/GYN &Midwifery - New Hanover to learn more about what you can expect.

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What is a full anatomy scan?

As babies grow and develop, around 18 to 20 weeks we can really see so many more of the solid organs, heart, limbs, hands and even within the brain. It’s a really important scan. There is no radiation from an ultrasound and it is safe in pregnancy.

Why is this so important?

If baby has a birth defect, we often will find it during this ultrasound. With the general anatomy scan, we really want to know that everything is normal. There are some birth defects that we’d want to know about right at delivery because maybe those need immediate management by the neonatal intensive care unit or by a pediatrician or a surgeon.


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What other potential problems can you spot in this scan?

Just because someone has an anatomy ultrasound that is completely normal, doesn't mean there is no birth defect. It just means that of the things that we can see, they look normal. We look at heart, lips, brain, spine, kidneys. We count the fingers and the toes, and actually the number of the bones in the fingers. Do the hands and the feet open and close? Are they at the right angles?

There are very subtle things that can be picked up on, but in addition to looking at the baby, we're also looking at the placenta, the amount of fluid around the baby. It takes about an hour for the ultrasonographer to complete this very detailed ultrasound.

If something abnormal is spotted in the scan, does that mean the baby will be born with that condition?

Some of that depends on what the abnormality is. An ultrasound image is created by the shadows we see as sound waves bounce back from the ultrasound probe to the tissue inside. The reason we can really see what's on the inside is because different tissues reflect these waves differently. The picture is of the shadows that are kind of glaring back.

So sometimes what we think we see on the ultrasound isn't always the case. For example, we see a little hole in the heart. What we don't know is, is that going to be a problem for the baby or not? Sometimes it is, and sometimes it isn't. Sometimes we see something that we're worried about, that turns out not to be a big deal.

Is there anything you can do if a condition is spotted?

There are a few conditions that can be managed, but most of the scans can just inform what the parents can expect about the baby or what kind of care the baby may need after delivery. The majority of the time everything looks normal. Most women get a good update.

Turning this into a more positive conversation, many Moms look forward to the full anatomy scan.

It's so exciting because people really get to see their baby! In earlier scans the baby is like a little gummy bear. It's still exciting when they’re tiny because you can see the little heartbeat. But this scan, it looks like a baby, and you can see it moving. You can really see the profile and the little arms and the hands and it really is neat. And for people who want to know the gender, a lot of times they get to find that out on this scan and that is exciting, too.

Is there anything else you would want expecting Moms at 18 to 20 weeks to know?

A lot of people around this time maybe start to feel a little bit better, as in they're not as fatigued or not as nauseated as they may have been in the beginning. Many pregnant people start to feel the baby move around this time as well, which is also fun.