Fetal heart rate of 163 at 21 weeks of pregnancy is abnormal and belongs to the accelerated fetal heart rate, which needs to be monitored and observed dynamically. The earliest time to see fetal buds and primitive heart tube pulsation during pregnancy is about 6 weeks after menopause, and the fetal heart sound can be heard on the abdominal wall with Doppler fetal heart stethoscope at about 12 weeks of pregnancy, and the normal fetal heart rate is 110~160 beats/min, so the fetal heart rate is too fast when the fetal heart rate is 163 beats/min at 21 weeks of pregnancy. During pregnancy, you should follow the doctor’s instructions for regular checkups, blood pressure and fetal heart rate monitoring. After the 28th week of pregnancy, you should count the fetal movements under the guidance of the doctor to self-assess the intrauterine condition of the fetus, and also regularly monitor the fetal heart rate changes, generally at about 32 weeks of pregnancy, you can follow the doctor’s instructions for fetal heart rate monitoring, you can continuously observe the dynamic changes in the fetal heart rate to ensure the safety of mothers and babies during pregnancy.