What is miscarriage and what are the causes of miscarriage?

The causes of miscarriage are complex and there are many of them. The more common causes of early miscarriage are chromosomal abnormalities, endocrine abnormalities, and uterine hypoplasia or malformations. So what are the common causes of miscarriage?

1. Chromosomal abnormalities Chromosomal abnormalities include abnormal chromosome number, such as monosomy, trisomy, and polyploidy; structural abnormalities, such as breakage, deletion, and translocation can all lead to miscarriage. Some people have conducted chromosomal research on spontaneous abortion and therapeutic abortion and found that karyotype abnormalities account for 60% of spontaneous abortions. Karyotype abnormalities are often accompanied by structural abnormalities such as in the fetus or placenta. However, the fetuses aborted by those with normal karyotype are mostly normal.

2. Endocrine disorders, excess estrogen and insufficient progesterone are also causes of early miscarriage. Because the placenta is formed and replaces the function of the corpus luteum of pregnancy during the 12th to 14th week of pregnancy, endocrine disorders are prone to occur, especially corpus luteum insufficiency. In addition, the lack of thyroid hormone hinders the cellular oxidation process, and hyperthyroidism and diabetes are prone to miscarriage.

3. Placental abnormalities and placental endocrine insufficiency. Decidualitis during early pregnancy can cause bleeding or hyperplasia of the basal decidua, dissolution of the chorionic epithelial cells and decidual cells, and blockage of blood vessels in the villi, affecting the absorption and transportation of nutrients, resulting in the separation of the fertilized egg from the attachment site, bleeding and miscarriage. In addition, huge infarction in the placenta can reduce the function of the placenta and affect the survival of the fetus; and placenta previa and placental villus edema and degeneration leading to miscarriage are not uncommon. After pregnancy, the levels of β-hCG, hPL, P, E2, and estrone in the mother's blood decrease during early pregnancy, resulting in 50% miscarriage.

4. Blood type incompatibility: Due to previous pregnancy or blood transfusion, the Rh factor and incompatible ABO blood type factor produce antibodies in the mother. During this pregnancy, the antibodies enter the fetus through the placenta and agglutinate with red blood cells to produce hemolysis, resulting in miscarriage.

5. Psychoneural factors such as fright, severe mental stimulation, etc. can also cause miscarriage. In recent years, research has shown that noise and vibration have a certain impact on human reproduction.