Fetal Ultrasound

Test Overview

Fetal ultrasound is a test done during pregnancy that uses reflected sound waves. It produces a picture, Opens dialog of the baby (fetus), the organ that supports the fetus (placenta, Opens dialog), and the liquid that surrounds the fetus (amniotic fluid, Opens dialog). The picture is displayed on a TV screen. It may be in black and white or in color. The pictures are also called a sonogram, an echogram, or a scan. They may be saved as part of your baby's record.

Fetal ultrasound can be done two ways. In a transabdominal ultrasound, a small handheld device called a transducer, Opens dialog is moved over your belly. In a transvaginal ultrasound, a transducer is put into your vagina.

Fetal ultrasound is the safest way to check for problems and get details about your fetus. It can find things such as the size and position of the fetus. It does not use X-rays, Opens dialog or other types of radiation that may harm your fetus. It can be done as early as the 5th week of pregnancy. Sometimes the sex of your fetus can be seen by about the 18th week of pregnancy.

Ultrasound is one of the screening tests that may be done in the first trimester to look for birth defects, such as Down syndrome, Opens dialog. The first-trimester screening test uses ultrasound to measure the thickness of the skin at the back of the baby's neck. This screening also includes blood tests that measure the levels of two substances that may be related to birth defects.

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Current as of: April 30, 2024

Author: Ignite Healthwise, LLC Staff

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