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

Loss of FHR variability can result from which of the following?

1. Maternal repositioning

2. Medications administration

3. Maternal hydration

4. Increased fetal movement

The correct answer is: Medications administration

Loss of fetal heart rate (FHR) variability is an important aspect to monitor during pregnancy and labor, as it can indicate the wellbeing of the fetus. Variability refers to the fluctuations in the FHR that are a normal response to several factors and reflect the autonomic regulation of the fetal heart. Medications can significantly affect FHR variability. For instance, certain medications such as analgesics, anesthetics, or drugs that act on the maternal or fetal nervous system may blunt the normal autonomic response, leading to a decrease in variability. These medications can alter fetal blood circulation and the fetal response to stress, thus affecting heart rate changes that typically occur during fetal movements or in response to contractions. In contrast, maternal repositioning and increased fetal movement generally enhance variability rather than diminish it. Changing maternal positions can improve blood flow to the fetus and may stimulate more variability as the fetus responds to the increased activity. Similarly, increased fetal movement is often associated with greater variability, as active fetuses typically show a range of heart rate changes. Maternal hydration plays a crucial role in ensuring adequate perfusion and can improve overall fetal condition, which may, in many circumstances, enhance FHR variability rather than diminish it. Understanding the potential impacts of medications on F