What does the "squiggly line" on a fetal heart monitor signify?

The "squiggly line" on a fetal heart monitor represents variability in the fetal heart rate. Variability indicates the fluctuations in the heart rate that can occur in response to different stimuli or conditions, which is a normal and healthy sign of fetal well-being. When there is a notable presence of variability, it suggests that the autonomic nervous system of the fetus is functioning well and that the fetus is responding appropriately to various environmental changes.

An absence of variability, or a very steady heart rate, might indicate potential issues with fetal oxygenation or distress, making the presence of variability an important aspect in assessing fetal health. This is why monitoring variability, often visualized as a squiggly line, is crucial for healthcare professionals during labor and delivery.