Emergency Department

202 S. Park St.
Madison, WI 53715

19 min Average

Patient Information: Targeted (20 Week) Ultrasound

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What is ultrasound?

Ultrasound is a technique that uses sound waves to visualize organs within the human body. The technique is popular in pregnancy because it allows you and your doctor to gain heath information about your baby without any risk to you or your baby. 

Who performs ultrasounds?

Trained sonographers and/or a doctor perform ultrasounds. At Meriter, a perinatologist interprets the ultrasound images. 

What is targeted ultrasound? 

There are many uses for ultrasound during pregnancy, such as during early pregnancy to confirm a pregnancy, verifying the due date, or as a genetic screen (e.g. First Trimester Screen). A targeted ultrasound is done later in pregnancy, usually around 20th week of the pregnancy. It is used to check the growth and development of your baby, check for birth defects and screen for certain types of genetic conditions, such as Down syndrome. 

When is the targeted ultrasound preformed?

Targeted ultrasound is usually performed around the 20th week of the pregnancy. 

Who has a targeted ultrasound?

Targeted ultrasound is offered to women who may be at higher-than-average risk of having a baby with some type of concern, birth defect, or complication. A few of the many reasons that a woman may need a targeted ultrasound include:

  • Health problems in the mother (i.e. diabetes, high blood pressure)
  • A family history of a birth defect
  • An abnormal blood screen (i.e. quad screen)
  • Mothers over 35 years of age
  • Mothers exposed to chemicals or medications during pregnancy
  • As a second opinion to rule out or confirm a concern seen at a different clinic

What information can I learn about my baby form targeted ultrasound?

Targeted ultrasound checks the overall growth of a baby. It is also used as a screen for birth defects and genetic conditions. The sonographer will look at many details of the baby, including the face, brain, heart, stomach, spine, kidneys, bladder, bones, hands and feet. If you like, you may also be able to find out the sex of your baby.

What kind of birth defects can ultrasound detect?

Ultrasound can often detect birth defects such as cleft lip, open neural tube defects, major heart defects, hydrocephaly, etc. It may not detect certain types of birth defects, such as some types of heart defects, small clefts of the soft palate or changes to the way the brain functions. 

What kinds of genetic disorders does ultrasound screen?

Ultrasound is used as genetic screen for Down syndrome, trisomy 18 and trisomy 13. The doctor uses ultrasound to identify any birth defects or clues that are more commonly seen in babies with any of these genetic conditions. Ultrasound cannot diagnose these genetic conditions, but rather it helps to estimate the chance of having a baby with one of these conditions.

How accurate is targeted ultrasound?

Under ideal conditions, ultrasound can be very accurate. However, like most medical tests, its accuracy is not perfect and is dependent on some of the following factors:

  • The experience of the sonographer and/or the doctor
  • The quality of the ultrasound equipment
  • The amount of fluid around the baby
  • The age and size of your baby

Even the most experienced doctors using the best equipment can miss some birth defects. Therefore, although anormal ultrasound is reassuring, it is not considered a guarantee for a healthy baby. 

When will I find out the results of the targeted ultrasound? 

You will find out the results from the ultrasound on the same day. Occasionally, the doctor may consult with other specialists before giving you final results. 

What if the doctor finds a problem? 

The doctor and a genetic counselor will meet with you right away if a birth defect is identified or if there is any suspicion that your baby has a genetic condition. You will be told as much as possible about the concern or condition and what it could mean for your baby’s health. Testing options, such as amniocentesis, maternal serum screening or future ultrasounds may be presented to you. In some instances you may be faced with difficult decisions. Regardless, you will be well informed and have the full support and guidance of your health care providers. 

Can I decide not to have the targeted ultrasound? 

Yes. Your genetic counselor will thoroughly explain and discuss the risks and benefits of targeted ultrasound with you. You then can decide whether or not you would like to have this test. 


Please feel free to contact us if you have any questions or concerns (608) 417-6667. Also, please visit our website (unitypoint.org) for more information about other services provided at Meriter’s Center for Perinatal Care Clinic.