Medically Reviewed By William C. Lloyd III, MD, FACS
— Written By Sarah Lewis, PharmD
Updated on May 1, 2020
What is fetal monitoring?
Fetal monitoring is the process of checking an unborn baby’s heart rate. Doctors usually perform fetal monitoring during labor and delivery, but may also need to do it during late pregnancy. There are two types of fetal monitoring:
- Auscultation involves periodically checking the baby’s heart rate. It uses a stethoscope or Doppler transducer to listen to the heart rate. The transducer is the same equipment doctor’s use to check your baby’s heart rate during prenatal visits.
- Electronic monitoring is continuous and can be external, internal or both. External monitoring records the heart rate using a fetal monitoring Doppler belt around the abdomen. Internal monitoring places an electrode on the part of the baby closest to the cervix. In most cases, this is the baby’s scalp.
The type of monitoring your doctor uses depends on several factors. This includes their practice policy, the hospital’s policy, your risk factors for problems, and the progress of your labor.
Why is fetal monitoring performed?
A baby’s heart rate can help doctors determine if pregnancy and labor are progressing normally. Changes in the baby’s heart rate can be a sign of a potential problem. The average heart rate for an unborn baby ranges from 110 to 160 beats per minute. This rate can normally vary by anywhere from 5 to 25 beats per minute. Changes outside this range may mean your baby is experiencing a problem, such as not getting enough oxygen.
Fetal monitoring during labor is especially helpful for high-risk pregnancies. It can help your doctor decide if there is a treatable problem or if a C-section delivery is necessary for safety.
Who performs fetal monitoring?
Members of your healthcare or labor team will perform fetal monitoring. In some cases, an obstetrician/gynecologist (Ob/Gyn) will perform it. Ob/Gyns specialize in the health of women, including pregnant women and their unborn babies. Ob nurses may also perform the procedure. Alternative providers, such as midwives, may use fetal monitoring as well.
How is fetal monitoring performed?
Fetal monitoring can take place in a doctor’s office before labor or in a hospital or alternative site during labor and delivery.
What to expect with auscultation
With auscultation, your provider will listen to your baby’s heart rate at set times during labor. They will do this by placing a stethoscope or Doppler transducer on your abdomen. Ultrasound gel can help the transducer make better contact with your skin.
What to expect with electronic monitoring
Electronic monitoring continuously checks your baby’s heart rate and sends it to a screen your provider can read. Your provider can also print the recording if necessary.
- With external monitoring, your provider will place two belts around your abdomen. One checks your baby’s heart rate with a Doppler transducer. The other monitors the length and frequency of your contractions.
- With internal monitoring, your provider will place an electrode on your baby. It goes on the part closest to your cervix, which is usually the baby’s scalp. Your provider may also place a uterine pressure catheter to monitor uterine contractions. Because this method invades the uterus, doctors can only use it after your amniotic sac ruptures—or your water breaks. Sometimes, the doctor needs to artificially rupture the sac to start internal monitoring. Your cervix also needs to be dilated several centimeters to allow internal monitoring.
You will need to stay in bed with both types of electronic fetal monitoring.
What are the risks and potential complications of fetal monitoring?
There are no physical fetal monitoring risks with auscultation or external fetal monitoring. Internal fetal monitoring carries a small risk of infection since it invades the uterus. The electrode can also leave a mark, bruise or cut on your baby, which usually heals quickly. HIV positive mothers should not have internal fetal monitoring, as there is a chance of infecting the baby.
Changes in a baby’s heart rate does not always mean there is a problem. However, using electronic fetal monitoring increases the chance of having a forceps-assisted, vacuum-assisted, or C-section delivery.
Certain factors can reduce the accuracy of fetal monitoring including:
- Maternal obesity
- Polyhydramnios, which is too much amniotic fluid
- Position of the baby or mother
How do I prepare for fetal monitoring?
For fetal monitoring during pregnancy, you may need to have a full bladder. Your provider will go over any preparation necessary for fetal monitoring during labor. In general, there is little to no preparation for auscultation and external monitoring.
For internal monitoring, your cervix must be dilated several centimeters and your membranes must be ruptured. If this hasn’t happened naturally and you need internal monitoring, your provider will explain the steps necessary to start the monitoring.
Questions to ask your doctor
It’s important to consider the need for fetal monitoring as part of your birth plan. Questions you may want to ask your doctor include:
- What is your policy for fetal monitoring?
- Under what circumstances will you use fetal monitoring?
- When do you use auscultation vs. external vs. internal fetal monitoring?
- Do I have risk factors that make fetal monitoring necessary? Which kind is best for me and my baby?
- What other testing might I need along with fetal monitoring?
- How do you decide whether my baby is having problems during labor and delivery?
- What would prompt you to move to forceps, vacuum-assisted, or C-section delivery?
What can I expect after fetal monitoring?
Knowing what to expect can ease your mind during labor and delivery. This includes knowing what to expect with fetal monitoring.
How long will it take to recover?
There is no specific care or recovery after fetal monitoring. Your diet and activity will depend on your delivery experience. If you had internal monitoring, your provider will check your baby for any wounds and clean them as necessary.
Will I feel pain?
You should not feel pain with fetal monitoring. However, you may feel some discomfort with external monitoring belts. The straps are adjustable, so tell your provider if you are uncomfortable.
With internal monitoring, you may feel discomfort during electrode placement. It requires a vaginal exam to check for cervical dilation. You may also feel discomfort if your doctor needs to rupture your amniotic sac. The discomfort comes from the instrument going through your cervix. It doesn’t hurt you or your baby when the sac breaks.
How might fetal monitoring affect my everyday life?
Fetal monitoring may have no effect on your life once labor and delivery is complete. However, you may end up needing a C-section delivery if your doctor identifies problems with your baby or your labor. This will involve a longer and different recovery than a vaginal delivery. Still, a C-section may be the safest option for both you and your baby.