Health Dictionary
Reliable, easy-to-read patient information on common medical conditions — written in plain language, free of jargon, and grounded in current evidence. Browse the most frequent diagnoses, understand what they mean for everyday life, and learn which steps and questions help you have a focused conversation with your doctor.
NST
Introduction
Overview
Overview
The nonstress test or NST is a Doppler time series recording of the heart beat of a fetus in utero simultaneous with the abdominal and/or uterine contractions of the pregnant woman.
Interpretation
Interpretation
- The NST is part of the biophysical profile, a formal prenatal test for fetal well being.
- The NST is considered reactive (a good sign) if the fetal heart rate has two accelerations in 20 minutes that (1) are at least 15 beats per minute above the baseline heart rate and (2) last for at least 15 seconds.
- A sleeping fetus, which appears nonreactive, can be awakened. This is often done by giving the woman a drink that is cold and/or sugary.
Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]