Which of the following signs may indicate a need for immediate intervention during fetal heart monitoring?

Persistent late decelerations are a critical sign during fetal heart monitoring as they indicate a potential issue with the oxygen supply to the fetus, often associated with uteroplacental insufficiency. These decelerations occur after a contraction begins and can signify that the fetus is experiencing stress or compromised blood flow, which may warrant immediate clinical intervention to prevent complications such as fetal hypoxia. Recognizing this pattern is essential for timely decision-making in obstetric care.

In contrast, increased fetal movement is generally considered a positive sign, indicating fetal well-being. An elevated baseline heart rate can sometimes be a sign of fetal distress, but it is not an immediate indication for intervention without other concerning factors present. High maternal blood pressure, while significant, requires monitoring and management but does not directly relate to fetal distress in the same urgent way that persistent late decelerations do.