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In this Article

• Introduction to prenatal ultrasound
• Is prenatal ultrasound safe?
• When is an ultrasound performed during pregnancy?
• What Is a 3-D and 4-D ultrasound?
• How should I prepare for a prenatal ultrasound?
• What happens during an ultrasound?
• What happens after a prenatal ultrasound?
• Will insurance pay for the ultrasound?
• Find a local Obstetrician-Gynecologist in your town
• Prenatal Ultrasound Index

Is Prenatal Ultrasound Safe?

Studies have shown ultrasound is not hazardous. There are no harmful side effects to you or your baby. In addition, ultrasound does not use radiation, as X-ray tests do.

When Is an Ultrasound Performed During Pregnancy?

An ultrasound is generally performed for all pregnant women around 20 weeks gestation. During this ultrasound, the doctor will confirm that the placenta is healthy and attached normally and that your baby is growing properly in the uterus. The baby's heartbeat and movement of its body, arms and legs can also be seen on the ultrasound.

If you wish to know the gender of your baby, it can usually be determined by 20 weeks. Be sure to tell the health care provider performing the ultrasound whether or not you want to know the gender of your baby. Please note that ultrasound is not a foolproof method to determine your baby's gender; there is a chance that the ultrasound images can be misinterpreted.

An ultrasound may be performed earlier in your pregnancy to determine:

• Presence of more than one fetus.
• Your due date or gestational age (the age of the fetus).

Later in pregnancy, ultrasound may be used to determine the:

• Health of the baby
• Placenta location
• Amount of amniotic fluid around the baby
• Position of the baby
• Baby's expected weight

What Is a 3-D and 4-D Ultrasound?

Newer ultrasounds are now available that show a three-dimensional view of the fetus. This is similar in clarity to a photograph and can be useful in detecting birth defects when performed in a medical center. Some facilities are providing this scan at the parents' request without a specific medical indication. A moving picture interpretation is referred to as a 4-D ultrasound. According to the March of Dimes, the FDA, as well as many other experts, the use of these non-medical ultrasounds is discouraged since untrained personnel may provide inaccurate or harmful information.

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