A primigravida at 37 weeks with decreased fetal movement has a prescription for routine fetal surveillance testing. Which test is most appropriate for initial fetal surveillance?

A primigravida at 37 weeks with decreased fetal movement has a prescription for routine fetal surveillance testing. Which test is most appropriate for initial fetal surveillance?

• A. Biophysical Profile
• B. Contraction Stress Test
• C. Nonstress Test (NST)
• D. Ultrasound

Answer: (C)

Evaluating a fetus with decreased movement at term starts with a test that watches how the fetal heart rate responds to the baby's own movements. This noninvasive test, called the nonstress test, quickly shows whether the heart rate increases with activity, which reflects good oxygenation and a responsive fetal nervous system. A reactive result—heart rate accelerations with movement within about 20 minutes—suggests the fetus is doing well, so no further testing is immediately required. If the nonstress test isn’t reactive, clinicians move to more detailed surveillance. A biophysical profile adds ultrasound assessments of movement, muscle tone, breathing, and amniotic fluid to provide a broader picture of fetal well-being. A contraction stress test evaluates how the heart rate responds to controlled contractions, but this is more invasive and typically reserved when the initial NST is nonreactive or when labor is imminent. Ultrasound alone doesn’t assess the real-time heart rate response to movement, so it isn’t the best starting point for initial fetal surveillance in this setting.

Evaluating a fetus with decreased movement at term starts with a test that watches how the fetal heart rate responds to the baby's own movements. This noninvasive test, called the nonstress test, quickly shows whether the heart rate increases with activity, which reflects good oxygenation and a responsive fetal nervous system. A reactive result—heart rate accelerations with movement within about 20 minutes—suggests the fetus is doing well, so no further testing is immediately required.

If the nonstress test isn’t reactive, clinicians move to more detailed surveillance. A biophysical profile adds ultrasound assessments of movement, muscle tone, breathing, and amniotic fluid to provide a broader picture of fetal well-being. A contraction stress test evaluates how the heart rate responds to controlled contractions, but this is more invasive and typically reserved when the initial NST is nonreactive or when labor is imminent.

Ultrasound alone doesn’t assess the real-time heart rate response to movement, so it isn’t the best starting point for initial fetal surveillance in this setting.