The fetal heartbeat can be heard through the fetal heart monitor after the 13th week of pregnancy, and the fetal heartbeat can be heard through the stethoscope in the 18th to 20th week of pregnancy. Generally, the original fetal heartbeat can be seen through ultrasound examination on the 50th to 60th day of pregnancy, and the fetal heartbeat cannot be heard through the fetal heart monitor at this time for the time being. After 12 weeks of pregnancy, the development of the fetus in the uterus is more stable, after 12 weeks of pregnancy, you can do the first pregnancy checkups, generally in the 13th week of pregnancy through the fetal heart monitor can hear the fetal heart. Stethoscope to listen to the fetal heart time is relatively late, generally in 18 ~ 20 weeks of pregnancy can be judged, the normal fetal heart rate of 110 ~ 160 beats / min, occasionally continued for a short period of time is normal, high or low, more than 10 minutes the fetal heart rate is lower than 110 beats / min or higher than 160 / min is considered to be anomalous. Through the fetal heart rate can also be a general understanding of the fetal development in the uterus whether there are abnormalities, there are abnormalities in time for further treatment.