There are many reasons why the fetal heart rate does not pass the test, it may be due to the fetus itself or the pregnant woman’s body. 1. Fetal reasons: if the fetus is sleeping, the fetal heart rate may be low, the pregnant woman can try to appropriate activities or play soft music to wake up the fetus, the pregnant woman can be rechecked again after 30 minutes. If the umbilical cord around the neck of the fetus will also make the fetal heart rate monitoring failed. 2. The cause of pregnant women: If the pregnant woman herself has a cold and fever, taking drugs, hypoxia, pregnancy complications, etc. can also lead to rapid heart rate of the fetus, fetal heart rate monitoring failed. If the fetal heart rate monitor fails several times, you should see a doctor in time to see if the fetus is in distress, placenta previa, etc. It is recommended to actively seek medical advice. It is recommended to actively seek medical advice and follow the doctor’s instructions for examination and treatment.