Monitoring your baby’s heart rate is a routine part of labor and delivery. During labor, you may hear nurses, midwives, or doctors mention terms like “early decelerations,” “variable decelerations,” or “late decelerations.” Hearing unfamiliar medical language during labor can feel overwhelming, especially if you are unsure what those terms mean.

The good news is that not all fetal heart rate decelerations are dangerous. In fact, early fetal heart rate decelerations are usually considered a reassuring sign that labor is progressing normally.

Here’s what early fetal heart rate decelerations mean, why they happen, and what providers are looking for when monitoring fetal heart rate patterns during labor.

What is Early Fetal Heart Rate Deceleration?

An early fetal heart rate deceleration is a decrease and return of your baby’s heart rate associated with a contraction. When you’re in labor, your medical team will monitor the fetal heart rate to ensure their well-being. Fetal heart rates are classified as Category 1 (reassuring), Category 2, and Category 3 (concerning) to help doctors determine necessary interventions.¹

These categories help providers quickly understand how well a baby is tolerating labor and whether closer monitoring may be needed.

Related: Medical Interventions You Might Need During Pushing

Why Will We Monitor My Baby’s Heart Rate?

Monitoring your baby’s heart rate during labor indicates how your baby is tolerating labor. The goal is to identify whether your baby must be delivered soon or immediately due to hypoxia or low oxygen levels.²

A scientist introduced electronic fetal heart rate monitoring before the 1960s, with the first clinical use in the late 1960s. While there doesn’t seem to be any benefit to your baby from fetal heart rate monitoring, it has become the standard of care in the United States. And it is a means to determine whether your baby is getting enough oxygen.

Monitoring also helps providers recognize when a baby may need closer observation or additional support during labor.

Continuous fetal heart rate monitoring during labor has increased C-sections, instrumental vaginal births, and maternal infection. Still, it has not reduced the risk of fetal cerebral palsy or death.^3,4,5

How Will Doctors Monitor My Baby’s Heart Rate?

Providers can monitor your baby’s heart rate in a few different ways during labor.

External Electronic Fetal Heart Rate Monitoring

External electronic fetal heart rate monitoring is the most common form of fetal heart rate monitoring. It involves using a small ultrasound monitor that your nurse straps to your abdomen. The fetal heart rate prints onto a strip of paper, and a second monitor measures your contractions and prints them on the same document.⁷

Related: What Do Contractions Feel Like? What You Need To Know About Labor Pains

Internal Electronic Fetal Heart Rate Monitoring

An internal electronic monitor, or scalp electrode, is sometimes used to obtain a more accurate, continuous reading of your baby’s heart rate. Your doctor or midwife places the monitor under the skin of your baby’s head during a cervical exam. This device also prints the results onto a strip of paper.⁷

Related: Cervical Check: What Dilation, Effacement, and Station Mean

Intermittent Auscultation (Listening Periodically)

This is a way to listen to and count your baby’s heart rate for short periods. It depends on the hospital or birth center protocols where you deliver and how often and for how long your baby’s heart rate will be listened to. If you have pain medication during labor, this is usually not an option. A nurse or midwife uses a handheld device to listen to your baby’s heartbeat.^6,7

Types of Decelerations

Three primary decelerations, or “drops” or “dips,” can happen with a baby’s heart rate. Let’s briefly look at each one, as you may hear these terms when you are in labor. Understanding the differences between these decelerations can make all of the labor terminology feel a little easier to follow.

Variable Fetal Heart Rate Decelerations

Variable decelerations are sharp decreases in the fetal heart lasting between 15 seconds and less than two minutes. These decelerations are usually caused by squeezing your baby’s umbilical cord. Your provider’s actions depend on where you are in labor and how severe the decelerations are. However, they are common, and variable decelerations do not always indicate a problem.⁸

Late Fetal Heart Rate Decelerations

Late deceleration is a slow decrease in the fetal heart rate that starts after the beginning of a contraction. This type of deceleration can sometimes happen when a baby is not getting enough oxygen during labor and is considered the most concerning type of fetal heart rate deceleration.⁸

Early Fetal Heart Rate Decelerations

Early fetal heart rate decelerations are also slow decreases in the fetal heart rate, but they mirror the contraction. The lowest part of the heartbeat is at the peak of the contraction. Early deceleration occurs when the baby’s head is squeezed or compressed during contractions. There is no effect on your baby’s oxygenation.⁸

Why Early Decelerations Are Usually Reassuring

Early fetal heart rate decelerations happen when your baby’s head is squeezed during contractions. The vagus nerve is stimulated when the head is squeezed, and the heart rate drops.

As labor progresses, your baby’s head will move lower in your pelvis, and contractions will become stronger. And these two things often lead to early decelerations. Early fetal heart rate decelerations usually indicate that your labor is progressing and that it will soon be time to push. This is often a reassuring sign that labor is progressing normally.¹

Related: How to Push During Childbirth: Positions and Tips That Help

Keeping you and your baby safe during labor is always a priority. One way to do that is to monitor your baby’s heart rate. Intermittent auscultation may be a good option if you are low risk and your baby is doing well. Fetal heart rate deceleration often occurs during labor, and variable and late decelerations can be concerning. However, early fetal heart rate decelerations usually indicate that labor is progressing. Remember to ask your nurse or provider if you have questions about fetal heart rate patterns during labor.

Labor can feel overwhelming at times, but understanding what providers are monitoring can help you feel more informed and reassured during the process.