How to Read a Fetal Monitor During Labor

Fetal monitoring, in one form or another, has been around for a long time—over 350 years, in fact. Prior to the 1970s, a health care provider (usually a doctor, nurse, or midwife) would use a stethoscope designed for pregnancy (fetoscope) to listen to the heart sounds (auscultation) of a fetus.

The technology for electronic fetal monitoring arrived in the 1960s and 1970s but had to undergo (and pass) reliability testing before hospitals and clinics started to use it. Electronic fetal monitors provided a graph (on a paper printout at first, and later, on a computer screen) that showed how a fetus's heart rate responded to contractions.

An advantage of electronic monitoring over the fetoscope method was that it could be done without requiring the provider to be at the patient's bedside.

Fetal monitoring is one way your provider can monitor how well your baby is coping with labor.

Here's a quick overview of how electronic fetal monitoring is used as well as how to interpret what you see (and hear) on the monitor.

1

Understand Your Labor

Pregnant woman having fetal monitoring
Johner Images / Getty Images

Fetal monitoring can be performed in several ways, depending on the needs of the patient and the capabilities of the facility. Physically, fetal monitoring can be done externally or internally. The timing of the monitoring can be continuous or intermittent.

The American College of Obstetricians and Gynecologists (ACOG) states that intermittent fetal monitoring with an electronic fetal monitor, handheld doppler, or stethoscope can be used to monitor low-risk women during labor.

2

What Electronic Fetal Monitoring Measures

Contractions and Fetal Heart Rate

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Electronic fetal monitoring produces a display on a computer monitor or paper graph that records the fetal heart rate and contractions. In the image above, you can see the fetal heart rate marked with the blue indicator. Contractions are in red.

When you're looking at the screen, the fetal heart rate is usually on the top and the contractions at the bottom. When the machine prints out graph paper, you'll see the fetal heart rate to the left and the contractions to the right.

Sometimes it's easier to read printouts by looking at them sideways.

The monitoring strip in the labor room will also be visible from a bank of monitors at the nurses' desk, which lets staff watch the monitors without having to come to a patient's room.

3

The Y Axis of Fetal Monitoring

Fetal monitoring basics

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On the left-hand side of the image above, you'll see a y-axis in each of the graphs. The blue indicator shows the marking of the fetal heart rate. These are beats per minute (bpm), which are measured in increments of ten with markings every 30 beats.

On the bottom and to the left is the y-axis (red indicator) with millimeters of mercury (mmHg), which measures the strength of a contraction. The higher number, the stronger the contraction.

Unless you are using an internal uterine pressure catheter (IUPC), this measure simply provides a graphical representation of each contraction.​

4

The X Axis of Fetal Monitoring

Measurements on Fetal Monitoring

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The horizontal line, or x-axis, is measured in minutes. Between the blue and red indicators is a single minute. Within each minute are lighter lines, each of which measures a ten-second increment. There are six sections for every minute.

Combining both the top and bottom (x and y-axes), the graphs line up with the heart rate directly above a contraction that is happening at the same time.

Once you are settled in your labor room, ask your nurse, midwife, or doctor for a quick tour of the fetal monitoring strip or monitor.

5

What Type of Monitoring Is Best for You?

Pregnancy ultrasound
MICHAEL DONNE/SCIENCE PHOTO LIBRARY / Getty Images

No single type of fetal monitoring will be right for everyone. The amount of time between checking on the baby and labor will differ from person to person—and even labor to labor in the same person. If your labor is considered high-risk, you will likely need to have continuous fetal monitoring.

You might need continuous fetal monitoring if you:

  • Are experiencing fetal distress in your current labor
  • Are having an epidural
  • Are having an induction of labor
  • Have certain medical conditions
  • Have had a previous cesarean birth
  • Have had multiple babies

A Word From Verywell

When you're in labor, fetal monitoring helps your healthcare team monitor how your baby is coping. There are different types of fetal monitoring, and the kind you will need will depend on your situation, as well as your provider's preference.

Start having a conversation with your provider about fetal monitoring at your prenatal visits. Ask them how they use fetal monitoring during labor, including when they would recommend continuous or internal fetal monitoring.

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