The 20 week ultrasound, for many this is the much-anticipated “gender reveal” ultrasound. So exciting! But, what many women don’t know, is how important this anatomy ultrasound is in evaluating your baby’s overall health. If you only want to get one ultrasound your entire pregnancy, hands down, this is the one you need. Congenital Heart Defects are the most common birth defect and most common cause of infant mortality. CHD is not always detected on ultrasound but most of the more critical defects can be. So, as you get ready for this appointment, certainly be excited about the gender reveal, but also know the questions to ask about your baby’s heart.

Profile of a baby at the 20 week anatomy ultrasound.
Calvin, age 18 weeks, the day we found out the right side of his heart was severely underdeveloped.

Are Ultrasounds safe?

First, I want to debunk a myth really quick. Ultrasounds are 100% safe and will not harm you or your baby. Ultrasound technology uses sound waves (outside the range of human hearing) to create an image of your baby. Doctors have been using this technology for over 50 years. Over this time, numerous research studies have shown no negative effects of ultrasound during pregnancy. This anatomy ultrasound has the potential to detect any major health problems that might cause your baby to need immediate attention after birth. Don’t skip it!

Personally, I know Calvin would have had a much scarier birth if we did not know about his heart defect ahead of time. Because we knew, a NICU team and a cardiology team were on standby at the time of his birth. As soon as he was born they started an IV with medicine to help his heart right there at my bedside. Knowing what he needed ahead of time may very well have saved his life.

What to ask at your 20 week ultrasound

The anatomy ultrasound is a level 2 scan usually performed between 18-22 weeks gestation. At this age, all of the body’s structures are finally big enough to view. As a bonus, the baby still has plenty of room to move around for the whole body to be seen (if they cooperate). At 20 weeks the baby’s heart is about the size of your thumbnail. So tiny! Here are 4 questions you can ask about your baby’s heart to rule out some of the more critical forms of CHD.

4 important questions about your baby’s heart:

Are all 4 chambers visible and functioning?

Do the main vessels leading out of the heart cross each other as they exit?

Are the walls between the chambers of the heart intact without any holes?

Are all the valves of the heart visible and functioning?

An ultrasound image of the heart with all 4 chambers visible.
A heart ultrasound where all 4 ventricles are visible.

Here’s a graphic I made for Project Heart a couple years ago as a quick shareable guide. If the answer to all four of these questions is yes, then that rules out many of the more complex congenital heart defects. Not all CHDs can be seen on ultrasound, but knowing as much as possible at your 20 week scan will hopefully give you some good peace of mind. Now, go enjoy seeing your baby!

Pregnant woman laying with her feet propped up on a baby crib. Lists 4 questions to ask about the heart.
My sweet preggo SIL, Aly as our heart ultrasound poster model 🙂 Photo Cred: Nicole Keyes, CNK Photography.

Has your baby recently been diagnosed with CHD in utero? You may also enjoy reading Questions to ask your Child’s Heart Surgeon.