Fetal Doppler

Reviewed by Amita Shroff, MD on August 28, 2022

What Is a Fetal Doppler?

A fetal Doppler is a test that uses sound waves to check your baby’s heartbeat. It’s a type of ultrasound that uses a handheld device to detect changes in movement that are translated as sound.


How Early Will a Fetal Doppler Test Work?

Most women first hear their baby's heartbeat during a routine checkup that uses the fetal Doppler. Many ultrasound machines also allow the heartbeat to be heard even before it can be heard with a Doppler. Most women now get an ultrasound before 12 weeks.

A fetal Doppler test normally takes place during your second trimester (weeks 13 to 28 of pregnancy). Some manufacturers of at-home fetal Dopplers say you may be able to hear your baby’s heartbeat as early as 8-12 weeks of pregnancy. But professional sonographers say that they wouldn’t try to listen to a baby’s heartbeat before 13 weeks because your womb is in your pelvis during the first trimester and so the device won’t work correctly. Some at-home devices say not to use it before 16 weeks.

If you’re trying to hear your baby’s heartbeat at home, it may be best to first wait for your doctor to check it during one of your prenatal checkups. This is especially true if you’ve been pregnant for less than 12 weeks, to avoid undue concern. It’s a good idea to talk to your doctor first before buying an at home fetal Doppler. They can talk to you about the benefits and risks involved with using these devices.


How the Fetal Doppler Test Is Done

Clinical fetal Doppler test

If you go to your doctor’s office or clinic, you'll lie down and a technician will hold a small probe against your belly that makes sound waves. Technicians will ask you to stay still while this is going on. The sound waves will then be sent back to an amplifier where they can be heard. The procedure is safe and painless.