Am Fam Physician. 2009;80(12):1398
See related article on intrapartum fetal monitoring.
What is electronic fetal monitoring (EFM)?
EFM is a way for your doctor to know how your baby is doing when you are in labor. During prenatal visits, patients usually decide if they want to use EFM. Even if you decide not to use it, your doctor may recommend that you change to a different type of monitoring if there are concerns during labor.
How does it work?
There are two devices—one that measures your contractions and one that measures your baby's heartbeat. They are usually placed on your stomach. If that doesn't work well, your doctor may need to use a device that goes inside your body. One can be placed on your baby's head to measure your baby's heartbeat. Another device fits between your baby and the wall of your uterus (womb). This can check how strong your contractions are if your labor is not moving along.
What do the lines on the EFM mean?
The top line shows the baby's heartbeat. Certain patterns can show how your baby is handling labor. The bottom line shows your contractions. Comparing your baby's heartbeat with your contractions shows how your baby is handling the labor.
Your doctor will watch to make sure your baby's heartbeat does not get too low during your contractions. If it does, your doctor may have you change positions and give you oxygen. If the problem continues, you may need to have an assisted or cesarean delivery.
Can EFM measurements be wrong?
EFM is not always accurate. It is just one tool that your doctor may use to help make decisions while you are in labor.
Where can I get more information?
Your doctor
American Academy of Family Physicians
Web site: https://familydoctor.org
The American College of Obstetricians and Gynecologists
Web site: http://www.acog.org/publications/patient_education/bp015.cfm
Childbirth.org
Web site: http://www.childbirth.org