What does variability in fetal heart rate indicate?

Variability in fetal heart rate is an important indicator of fetal well-being. It reflects the fetus's ability to respond to changes in the environment and indicates an intact autonomic nervous system. Normal variability implies that the fetus is not experiencing distress and is generally in a healthy state. It is characterized by fluctuations in the fetal heart rate that are measured over time and is often classified as absent, minimal, moderate, or marked. Moderate variability, which is considered the most reassuring, typically suggests that the fetus is receiving adequate oxygen and is able to respond appropriately to stimuli.

In contrast, limited or absent variability can be associated with fetal compromise or other adverse conditions, while stable conditions or maternal hyperactivity may not directly correlate to the fetal heart rate variability observed. Thus, recognizing variability as a marker for normal fetal well-being is crucial in monitoring and assessing fetal health during pregnancy.