There is a folk saying that a fetus with a heart rate below 140 beats per minute is a boy, while a fetus with a heart rate above 140 beats per minute is a girl. Generally speaking, a girl’s heart rate is higher than a boy’s, and it has nothing to do with the sex of the fetus. A girl’s heart rate is higher than a boy’s, but this is only true at birth; there is no difference between the heart rate of a boy and a girl. The normal fetal heart rate is between 120 beats/min to 160 beats/min, listening to the fetal heart requires the use of special equipment, about 12 weeks of pregnancy can be heard with a Doppler stethoscope in a very quiet situation, while if you use the obstetric stethoscope until 18 weeks of pregnancy to hear the fetal heart, even in late pregnancy, using an ordinary stethoscope to listen to the fetal heart is not an easy task. The speed of heart rate varies only with gestational age. At about 5 weeks of gestation, the fetal heart rate is close to the mother’s heart rate, i.e. 80-85 beats per minute. The heart rate then gradually increases to 170-200 beats per minute by the 9th week of gestation. Then it gradually slows down to 120-160 beats/minute in the middle of pregnancy. The fetal heart rate is not a reliable indicator of male and female, instead, mothers should pay attention to whether the fetal heart is normal or not, and if the fetal heart is abnormal, they should seek medical attention as soon as possible. After a fetal movement, the fetal heart rate can briefly accelerate to higher than 160 beats per minute, but immediately return to normal, which is a good sign of fetal health. If the fetal heart rate is more than 160 beats per minute or less than 120 beats per minute, or irregular heartbeat, fast and slow, jumping and stopping, etc., it is abnormal. If you find that the fetal heart rate is always lower than 120 beats per minute or higher than 160 beats per minute within 10 minutes, or if the fetal heartbeat becomes slower, less responsive and less active after the fetal heartbeat is accelerated, please consult a doctor immediately for examination.