In pregnancy and during labor, your doctor will want to check the health of your unborn baby (fetus). This is done by check the baby’s heart rate and other functions. Monitoring can be done on the outside of your belly (external monitoring). Or it may be done directly on the baby while inside the womb (internal monitoring). Fetal monitoring is a very common procedure.
External monitoring may done with a special tool called a fetoscope. It’s a stethoscope that has a different shape. It may also be done using Doppler. This is an electronic tool that uses sound waves and a computer. Internal monitoring is done by putting a small sticky pad (electrode) on the baby’s head. This is done while it’s still in the mother’s womb.
Fetal heart rate monitoring is used to check the rate and rhythm of the heartbeats. It looks for any increases or decreases in the baby’s heartbeat. It also checks how much the baby’s heart rate changes. The average fetal heart rate is between 110 and 160 beats per minute. The fetal heart rate may change as the baby responds to conditions in the uterus. An abnormal fetal heart rate or pattern may mean that the baby is not getting enough oxygen or there are other problems. An abnormal pattern also may mean that an emergency cesarean (c-section) delivery is needed.
Using a handheld Doppler device to listen to the fetal heartbeat is the most basic type of fetal monitoring. This is often done during prenatal visits to count the fetal heart rate.
Fetal monitoring may also help show problems in the baby during late pregnancy and labor. It can show if other testing or a c-section may be needed.
There are no known physical risks for external monitoring with a fetoscope or Doppler. There may be a slight risk of infection with internal monitoring. The scalp electrode may also cause a mark or small cut on the baby's head, but this often heals quickly.
An abnormal fetal heart rate pattern doesn’t always mean the baby is in danger. But electronic fetal monitoring is linked with a greater chance for vacuum and forceps use, and for c-section delivery. Talk with your healthcare provider about these risks.
Preparing for fetal monitoring depends on if it is external or internal and if it is being done late in pregnancy or during labor.
For external fetal monitoring during pregnancy with a Doppler, you may need to have a full bladder. There is no restriction of food or drink. You’ll be given a consent form to sign. Make sure to ask questions if needed.
For fetal monitoring during labor, your healthcare provider will tell you if any preparation is needed.
The details may vary, but typical electronic fetal monitoring may go like this:
In some cases, you may need internal fetal monitoring for a more accurate reading of the fetal heart rate. This can only be done if your bag of waters (amniotic sac) is broken and your cervix is partially open (dilated). The provider puts a small, sticky pad called a fetal scalp electrode through the open cervix. It’s attached to the baby’s scalp. The electrode is attached to a wire. The wire sends information about the baby’s heartbeat to a computer.
After external fetal monitoring, the provider removes the straps and wipes the gel off your belly. After internal fetal heart rate monitoring, the provider checks your baby’s scalp and cleans it where the electrode was stuck.
Before you agree to the test or the procedure make sure you know: