Spontaneous miscarriage, especially in early pregnancy, is a great concern and worry for many pregnant mothers, and some of them are so worried about it that it even affects their normal life. An understanding of spontaneous abortion can help people get out of the misconceptions about miscarriage, regain confidence and regain courage to live. Spontaneous abortion occurs in up to 15% of identifiable pregnancies, and even more pregnancies end before they are detected. So it is not as easy as one might think for each fertilized egg to develop into a normal fetus. Therefore, spontaneous abortions are not uncommon, and chromosomal abnormalities can be found in at least 50% of them, while the rest are due to external and internal factors causing embryonic abnormalities or poor environment resulting in non-viability of the embryo. If a spontaneous miscarriage occurs, there is no need to worry too much as the chance of a successful next pregnancy is not lower than others. Gao Jinsong, Department of Obstetrics and Gynecology, Peking Union Medical College Hospital If 2 or more spontaneous miscarriages have occurred, some non-accidental causes need to be investigated, including: diabetes, thyroid disease, autoimmune disease, and chromosomal balance translocation of parents. In the case of unexplained miscarriage occurring in mid-trimester, the presence of uterine anomalies and relaxation of the endocervix need to be understood. If the cause is found and treated for the cause, the chances of a successful pregnancy next time will be greatly improved.