If you have seen the buds and heart of the fetus at 7 weeks of pregnancy and then lost them at 9 weeks of pregnancy, you should consider the case of fetal arrest, which may be affected by chromosomal abnormality of the embryo, endocrine disorders of the mother, and environmental factors. The fact that the buds and heart of the fetus have appeared in the 7th week of pregnancy indicates that the fetus is alive in the uterus, and the fact that the buds and heart of the fetus no longer appear in the 9th week of pregnancy indicates that the development of the embryo in the uterus has ceased, which is a kind of abnormal manifestation. Fetal arrest is more common in the early stages of pregnancy is the chromosomal abnormality of the embryo. It may also be caused by endocrine disorders of the mother, hormone level disorders in the body, not able to support the embryo pregnancy resulting in fetal arrest. Staying in a radioactive or polluted environment for a long period of time after pregnancy may also cause fetal arrest. In early pregnancy, there will be vaginal bleeding, lower abdominal pain, early pregnancy reaction gradually disappears to stop and other symptoms, to go to the hospital for another review, diagnosed with fetal arrest can not continue pregnancy. After pregnancy, regular pregnancy checkups, abnormalities should be dealt with in a timely manner.