External Electronic Fetal Monitoring

What is external electronic fetal monitoring?

Electronic fetal monitoring measures the baby's heart rate and the mother's contractions during labor. This may be done outside or inside the mother's body.

• An external monitor uses instruments placed on the mother's belly.
• An internal monitor uses instruments on the baby's scalp inside the mother's uterus.

The results of the monitoring can be seen as graphs on a screen. This information about the baby's heart rate and how it changes with contractions helps your healthcare provider know how the baby is doing during labor. It also shows how strong and frequent your contractions are.

When is it used?

Fetal monitoring is usually done the entire time you are in labor, but especially if your pregnancy is high risk. For example, continuous monitoring is needed in cases of:

• preterm labor
• a very small baby
• births of more than 1 baby, such as twins
• bleeding during labor
• medical problems with the mother, such as diabetes and preeclampsia
• changes in the baby's heart rate found with the stethoscope

In low-risk pregnancies, monitors may only be used for about 20 minutes at the start of labor, or for a few minutes each hour.

What happens during the procedure?

The instruments for external monitoring are held in place by 2 belts around the mother's abdomen. On one belt is a pressure gauge. The gauge records the pressure of contractions. Attached to the other belt is a small ultrasound instrument, which records the baby's heart rate. Monitoring is safe and fairly comfortable. You can change positions while the devices are in place, but movement sometimes disrupts the test recording.

When the baby's heart rate is normal, the monitor may be disconnected at times. You can then move more freely. In most cases the monitor is attached for a few minutes each hour. When the monitor is not being used, your provider may check the baby's heart rate with a stethoscope or fetoscope.

If the external monitor shows that the baby's heart rate is abnormal or your contractions are too frequent, an internal monitor may be used for more accurate information.

A heart rate that is too slow or does not change as it should with contractions may mean that the baby is not getting enough oxygen. Your provider may decide that the baby may not do well in a vaginal delivery. You may need to have a cesarean section (C-section).

What are the benefits of this procedure?

Fetal monitoring allows your healthcare provider to check the baby's response to labor. If the baby is not doing well, steps may be taken to help the baby. If the monitoring shows a normal pattern, it is reassuring to the mother and her provider.

What are the risks associated with this procedure?

External electronic monitoring has no known serious risks when it is used properly. However, sometimes the information from an external monitor is not completely accurate. The monitoring should be done by someone who is trained in interpreting it and who is able to carefully weigh other signs of the baby's health.