Final answer:
A reactive result to a non-stress test occurs when the fetal heart rate increases above the baseline by 15 beats per minute.
Step-by-step explanation:
A reactive result to a non-stress test occurs when the fetal heart rate increases above the baseline by 15 beats per minute.
The non-stress test is a prenatal test that measures the heart rate of a fetus. During the test, the baseline heart rate of the fetus is recorded. If there is an increase of at least 15 beats per minute from the baseline, it is considered a reactive result, indicating a healthy response from the fetus.