NCC Certified Electronic Fetal Monitoring (C-EFM) Practice Exam

What physiological response can trigger variable decelerations in the fetal heart rate?

1. Maternal hypertension

2. Abrupt rise in fetal blood pressure

3. Increased uterine contractions

4. Decreased maternal oxygen levels

The correct answer is: Abrupt rise in fetal blood pressure

Variable decelerations in the fetal heart rate are often associated with changes in the umbilical cord, which can lead to transient decreases in fetal heart rate due to cord compression. When there is an abrupt rise in fetal blood pressure, it can signal a physiological response that directly affects the heart rate in the fetus. This response may lead to variations in how the fetus is experiencing the labor process, including potential stresses such as decreased blood flow or oxygenation, contributing to those variable decelerations. The other options relate to different physiological processes. Maternal hypertension can affect placental perfusion but does not directly cause variable decelerations in the same way. Increased uterine contractions lead to decreased blood flow through uterine vessels, but this usually results in a pattern of deceleration known as early or late rather than variable. Decreased maternal oxygen levels can affect fetal oxygenation but are more likely to cause a bradycardic response rather than variable decelerations. Thus, the physiological response associated with an abrupt rise in fetal blood pressure is the most accurate connection to the scenario of variable decelerations.