Usually, the fetal heartbeat can be heard by Doppler examination around 6-8 weeks of pregnancy. The time of appearance of the fetal heart is related to the menstrual cycle of the pregnant woman and the early or late fertilization of the egg. For women with shorter menstrual cycles, the fetal heart appears earlier, for example, if the menstrual cycle is around 28 days, the fetal heart will appear around 45 days after menopause. For women with longer menstrual cycles, the fetal heart may appear later, for example, if the menstrual cycle is between 35-40 days, the fetal heart may appear around 55 days after menopause. In addition, if the fertilized egg is early and well developed, the fetal heartbeat will appear earlier, while if the fertilized egg is late, the fetal heartbeat will appear later. If the fetal heartbeat is detected by auscultation, it will not be heard until about 16 weeks of pregnancy. It is recommended that pregnant women should go to the hospital for gynecological ultrasound examination after 6-8 weeks of menopause to observe the fetal heartbeat.