The best time to do fetal heart monitoring depends on the condition of the pregnant woman and the fetus, mostly between meals is better, but special conditions should be decided according to the specific condition. Generally speaking, when doing fetal heart monitoring during maternity checkup, you should choose to do it between two meals, in good health, avoiding fatigue or hunger, and try to do it during the time when the fetus is relatively more active. If the fetus is in a quiet time of the day, the variability of the fetal heartbeat may not be ideal, resulting in false positive results of fetal heartbeat abnormalities. In case of emergency or abnormal conditions, such as decreased fetal movement or pregnancy complications, such as pre-eclampsia, fetal heart monitoring should be done at any time according to the condition, and the time cannot be freely chosen.