The most common procedure done on labor and delivery in the United States is electronic fetal monitoring, or EFM. This is when a monitor is applied on your abdomen in the form of a belt so that your baby’s heart rate can be heard and recorded. An internal monitor can also be used if necessary once your cervix is dilated and bag of water is broken. Internal monitors take the form of an electrode clip on your baby’s head.
The purpose of EFM is to let your doctor or midwife know how your baby is tolerating labor, with the overall goal being to decrease the number of babies who are born with complications such as seizures, brain damage, cerebral palsy, or a stillbirth. However, despite the fact that more than 85 percent of American babies are monitored this way, controversy still exists as to whether or not EFM is helpful or leads to unnecessary C-sections and operative deliveries.
Based on the rate of your baby’s heartbeat and patterns called accelerations or decelerations, your provider can make an educated guess about whether your baby is fine or if an urgent or emergent delivery might be needed. This is based on the idea that a baby’s heart rate will vary based on how much oxygen he or she is getting from the placenta. Too little oxygen could lead to a very abnormal heart rate pattern, for example.
EFM can be done continuously (when the baby is monitored throughout the entire labor) or intermittently (when the nurse will check the baby’s heart rate for a brief time at scheduled periods, such as every 15 or 30 minutes).
When a meta-analysis compared continuous versus intermittent monitoring, there was no difference in mortality or cerebral palsy between the two groups. This lack of change in cerebral palsy cases is likely because so few can actually be attributed to labor, with only about 4 percent of cases being the result of events in labor. On a good note, continuous EFM did decrease the risk of neonatal seizures. However, women who were continuously monitored were more likely to end up with a forceps or vacuum delivery or with a C-section.
So what do you need to know if your doctor or midwife wants you to be monitored in labor? Here are the high points:
- Given what we know, intermittent or continuous monitoring is considered acceptable in low-risk pregnancies.
- We don’t have good studies on how much monitoring is ideal when it comes to intermittent monitoring. One protocol discussed by the American Congress of Obstetricians and Gynecologists is to listen to the baby’s heart rate every 15 minutes in active labor and every 5 minutes once a woman is pushing.
- Continuous monitoring may increase your chance of an assisted delivery or a C-section, but it is recommended if your pregnancy is high-risk or your baby is preterm.
Reviewed by Dr. Jen Lincoln, April 2020
- Electronic fetal monitoring (EFM) is a way of monitoring your baby’s heartbeat in labor to assess how your baby is tolerating the labor process.
- EFM can be done internally or externally.
- The goal of EFM is to decrease the chance that your baby will be born with a complication such as seizures or cerebral palsy.
- Continuous fetal monitoring can lead to an increase in a forceps or vacuum delivery or a C-section.