Baby Ultrasounds: Different Types & What They Tell You
One of the most exciting times in your pregnancy is when you get to see your baby in an ultrasound image. Most women are familiar with standard baby ultrasounds, but did you know there are other types too?
What can each type of ultrasound tell you? Why would your doctor order an ultrasound? Are ultrasounds safe for you and your baby?
We'll answer each of these questions as well as look at how we use ultrasounds in prenatal screening tests here at NTD Eurofins.
Types of Baby Ultrasounds
You're no doubt familiar with the standard ultrasound—a prenatal test in which a technician moves a wand-like instrument called a transducer over your abdomen so you can see grainy, 2D images of your developing baby. (These images are called sonograms.) But did you know there are other kinds of ultrasounds too?
According to the American Pregnancy Association, there are seven different types.
Transvaginal Scans
During a transvaginal scan, a doctor places a specially designed transducer inside the vagina to generate images of your baby. A transducer is a probe that uses sound waves to produce an image. Your doctor will typically order a transvaginal scan during the early stages of pregnancy when your baby isn't big enough to get a good reading from your abdomen.
Standard Baby Ultrasounds
Standard ultrasounds are the traditional ultrasounds you're familiar with. They use a transducer over your abdomen to give 2D images of your baby.
Advanced Baby Ultrasounds
Advanced ultrasounds are just like standard ultrasounds, but they use more advanced equipment to get a clearer picture. Your doctor will typically order this type of ultrasound when looking for a suspected problem.
Doppler Ultrasounds
Doppler ultrasounds look at your baby's blood flow. Sound waves show how blood moves in your baby's heart, through the umbilical cord, and between your baby and the placenta.
3D Baby Ultrasounds
3D ultrasounds use sophisticated transducers and software to generate lifelike 3D images of your developing baby.
4D Baby Ultrasounds
4D ultrasounds are essentially the same thing as 3D, except they let the ultrasound technician show your baby moving in real time. They are also called dynamic 3D ultrasounds.
Fetal Echocardiography
Fetal echocardiography is a special test similar to an ultrasound. Sound waves are used to check on your baby's heart to be sure it's developing and working properly. Your doctor will most likely order a fetal echocardiogram if a congenital heart defect is suspected.
Purpose of Ultrasounds
Ultrasounds let you see your baby before she is born, but what else can they show? What are doctors looking for when they order an ultrasound?
According to the American College of Obstetricians and Gynecologists, your OB uses ultrasounds to check on your baby's development and look for congenital disorders. An ultrasound can also tell you how far along you are in your pregnancy.
Sometimes, baby ultrasounds are combined with other tests such as chorionic villus sampling (CVS) and amniocentesis. For CVS, your doctor will test a small part of your placenta. Amniocentesis tests a sample of your amniotic fluid. Both tests look for genetic conditions such as Down syndrome.
At NTD Eurofins, we use ultrasounds along with prenatal screening tests to determine your risk for having a baby with a genetic condition. Ultrasounds confirm how far along you are, measure the nuchal translucency (NT), and assess the fetal nasal bone.
An NT test uses an ultrasound to look for fluid collection behind a baby's neck during the first trimester. This is an early indication of Down syndrome. According to an article in Ultrasound in Obstetrics & Gynecology, the absence of a fetal nasal bone may also indicate Down syndrome.
With NTD Eurofins, you have the option of adding the Fetal Nasal Bone Assessment to your First Trimester Screen. Including the Fetal Nasal Bone Assessment helps doctors raise the detection rate for Down syndrome. The false-positive rate is also lowered.
Risks and Side Effects of Ultrasounds
Ultrasounds are noninvasive procedures, but do they pose any risk to you or your baby? According to the U.S. Food & Drug Administration (FDA), ultrasounds have been used during pregnancy for many years and are considered safe.
However, the FDA discourages women from getting baby ultrasounds that aren't medically necessary. These include the 3D and 4D ultrasounds that some companies offer so parents can have keepsake sonogram images of their baby.
If you're already having an ultrasound done for medical purposes — like during your 20-week prenatal checkup — switching to a 3D or 4D ultrasound for better-quality pictures is okay. It doesn't require any additional exposure.
Throughout their pregnancy, most women will require only two or three of these ultrasounds. Usually, you'll have a transvaginal ultrasound to confirm your pregnancy early on. Later, you'll have a standard or advanced ultrasound to check on your baby's development.
Ultrasounds let you see your growing baby and are also helpful diagnostic tools. At NTD Eurofins, we offer many prenatal screening tests that use baby ultrasounds to give a more accurate risk assessment for genetic conditions. Visit our website to learn more.
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References
- American College of Obstetricians and Gynecologists. (2017). Ultrasound Exams. American College of Obstetricians and Gynecologists. https://www.acog.org/patient-resources/faqs/special-procedures/ultrasound-exams
- American Pregnancy Association. (n.d.). Ultrasound: Sonogram. American Pregnancy Association. https://americanpregnancy.org/prenatal-testing/ultrasound/
- Fetal Medicine Foundation. (n.d.). Nuchal Translucency Scan. Fetal Medicine Foundation. https://fetalmedicine.org/fmf-certification/certificates-of-competence/nuchal-translucency-scan
- Mayo Clinic Staff. (2019). Chorionic Villus Sampling. Mayo Clinic. https://www.mayoclinic.org/tests-procedures/chorionic-villus-sampling/about/pac-20393533
- Orlandi, F., et al. (2003). Measurement of Nasal Bone Length at 11-14 Weeks of Pregnancy and Its Potential Role in Down Syndrome Risk Assessment. Ultrasound in Obstetrics & Gynecology, 22(1). https://www.ncbi.nlm.nih.gov/pubmed/12858300
- U.S. Food & Drug Administration. (2019). Ultrasound Imaging. U.S. Food & Drug Administration. https://www.fda.gov/radiation-emitting-products/medical-imaging/ultrasound-imaging#benefitsrisks
The information provided represents the general opinions of NTD Eurofins and is not intended to be used as specific advice for any one individual. Individuals should always consult with a physician to obtain specific advice and to receive answers to any and all questions or concerns related to health, wellness, pregnancy, and birth.