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by McCoy K

Definition

Fetal heart rate (FHR) monitoring is listening to your unborn baby's heartbeat. There are 2 types:

  • External—A special device records the heartbeat through the belly.
  • Internal—A thin wire is threaded into the body and placed on the baby's head.

Reasons for Test

This can be done during pregnancy to see how well your unborn baby is doing. It is often done during labor to see how the unborn baby is handling the stress.

Possible Complications

There are no problems linked to external monitoring.

For internal monitoring, there is a higher risk of infection or bruising on the baby's head.

What to Expect

Prior to Test

Your doctor will tell you which type of monitoring will be used and how often. It can be done throughout labor or at certain times.

Your birth partner and care team will help you with a birth plan. You can think about what you like to happen and be ready to adjust if problems come up.

Description of the Test

External Fetal Monitoring

There are 2 ways to have external monitoring:

  • Two belts are placed around the belly. Gel is placed under the monitor. This records the unborn baby's heartbeat and tracks how well the uterus is contracting during labor. This type is used throughout labor.
  • The doctor uses a special scope to listen to the unborn baby's heart through the belly. This type is used at certain times.
External Fetal Monitoring
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Internal Fetal Monitoring:

This is only used during labor, after the water has broken and cervix has opened. A small wire is placed through the vagina and cervix. It is placed on the unborn baby's head. The wire picks up the unborn baby's heartbeat and sends it to a screen. It also tracks how well the uterus is contracting during labor. The internal type is not needed to have a truer reading. It may be used in certain situations.

After Test

The electrodes or belts will be removed.

How Long Will It Take?

It depends on if it is done throughout labor or at certain times.

Will It Hurt?

No

Results

The unborn baby's heart rate should be 110 to 160 beats a minute. An abnormal rate or pattern may show a problem with the unborn baby. The doctor may make changes based on the heart rate.

Call Your Doctor

This is only done during labor. There are no effects that your doctor will need to watch.

RESOURCES

Office on Women's Health  https://www.womenshealth.gov 

The American College of Obstetricians and Gynecologists  https://www.acog.org 

CANADIAN RESOURCES

The Society of Obstetricians and Gynaecologists of Canada  https://www.sogc.org 

Women's Health Matters—Women's College Hospital  http://www.womenshealthmatters.ca 

References

Fetal heart monitoring. Johns Hopkins Medicine website. Available at: https://www.hopkinsmedicine.org/healthlibrary/test%5Fprocedures/gynecology/external%5Fand%5Finternal%5Fheart%5Frate%5Fmonitoring%5Fof%5Fthe%5Ffetus%5F92,P07776. Accessed March 7, 2019.

Fetal heart rate monitoring during labor. The American College of Obstetricians and Gynecologists website. Available at: https://www.acog.org/~/media/For%20Patients/faq015.pdf?dmc=1&ts=20121220T0954532535. Updated February 2018. Accessed March 7, 2019.

Fetal monitoring during labor. EBSCO DynaMed Plus website. Available at:  https://www.dynamed.com/topics/dmp~AN~T115651/Fetal-monitoring-during-labor . Updated March 12, 2018. Accessed March 7, 2019.

Practice bulletin no. 145: antepartum fetal surveillance. Obstet Gynecol. 2014;124(1):182-192. Reaffirmed 2019.

Revision Information