The precursors of bad fetal heartbeat and buds may be reduced or disappeared early pregnancy reaction, the embryo stops developing, bad HCG doubling, and so on. 1. Early pregnancy reaction decreases or disappears. Fetal arrest may occur when the fetus has a bad heartbeat or bad buds, and the possible precursors are nausea, vomiting, loss of appetite, breast tenderness, etc. The early pregnancy reaction will be reduced or disappeared, and there may even be abdominal pain and vaginal bleeding. 2. The embryo stops developing. Fetal heart and fetal buds are not good as a precursor of fetal arrest, there will be no fetal heart and fetal buds can not be seen in ultrasound after 50 days of menopause, and the embryo does not develop normally. 3. HCG doubling is not good. The HCG in the body of a woman after pregnancy is doubled every other day, if the HCG in the body does not increase but decreases or grows slowly, the doubling is not good, it may be a sign that the embryo does not grow buds and the fetal heart. If you have a pregnancy with poor germination and fetal heartbeat, you need to check the cause with ultrasound and terminate the pregnancy if necessary.