The reasons for the non-development of pregnancy are manifold: 1. Fetal factors. There are chromosomal abnormalities in the fetus, or abnormal development of organs, leading to the cessation of embryonic development. There is a certain correlation with genetic factors, and factors such as infectious drugs can also lead to it.2. Placental abnormalities. In early pregnancy, the trophoblast is underdeveloped or the placental villi are degenerated, which reduces the function of the placenta and impairs the blood circulation, resulting in the embryo’s failure to develop.3. Maternal factors. A variety of factors lead to the pregnant woman’s internal environment is in an abnormal state, affecting the development of the fetus. For example, pregnant women suffer from serious systemic diseases, such as hypertension, chronic liver and kidney disease, chronic wasting disease, severe infection, severe anemia and heart failure, thrombotic diseases. Maternal endocrine function abnormalities, such as luteal insufficiency, polycystic ovary syndrome, hyperprolactinemia, hyperthyroidism or hypothyroidism, severe diabetes mellitus is not controlled. 4, the father factor. Chromosomal abnormalities in the male can cause the embryo not to develop normally, as well as sperm abnormalities, excessive smoking, alcoholism, etc. 5, environmental factors. Excessive exposure to chemical substances, such as arsenic, lead, formaldehyde, mercury, etc.; exposure to radiation, high temperature, high noise environment and so on.