1, high blood pressure: the standard of high blood pressure is 140/90mmHg or more, pregnant women in the 28 weeks of pregnancy before the occurrence of high blood pressure may be its own pre-existing diseases, such as blood pressure is not measured in the past is not easy to differentiate from gestational hypertension syndrome (another proteinuria > 3g / L, and edema), but can also be both. Placental and uterine blood flow is reduced in hypertensive syndrome, fetal intrauterine hypoxia, growth retardation, and even stillbirth, need treatment. 2, diabetes: diabetic pregnant women, such as pre-pregnancy symptoms are mild, post-pregnancy symptoms can be relieved, and only need to regulate the diet, such as the symptoms of the more serious, still need to be treated with insulin, and there are pregnant women who are only in the gestation period of diabetes. Before pregnancy has suffered from more severe diabetes and diabetes in pregnancy on the fetus is not the same, pre-pregnancy diabetes is not controlled, after pregnancy is still dependent on insulin treatment of the fetus higher incidence of miscarriage, or may be congenital anomalies (eg, neural tube defects, congenital heart disease), live births of newborns may be stunted growth, but may also be a huge child. Fetuses with diabetes mellitus during pregnancy tend to be macrosomic, but are prone to hypoglycemia (or hyperglycemia), hypercalcemia, and/or hyperbilirubinemia. 3, autoimmune disease: autoimmune epidemic mainly affect connective tissue and arthritis. (1) Erythematous lupus erythematosus: often recurrent with intervals of quiescence. The fetus of the pregnant mother during the flare-up period is prone to miscarriage, premature labor and stillbirth or fetal growth retardation. Newborns delivered during intermittent periods have a higher survival rate. Pregnancy has little effect on autoimmune diseases. The effect of the disease on the fetus may be in the heart, where complete conduction block occurs, and pericardial effusion and edema rarely occur. (2) Rheumatoid arthritis: It has little effect on the fetus and does not increase perinatal mortality or morbidity. (4) Thyroid disease: untreated or uncontrolled hyperthyroidism in pregnant women is prone to the occurrence of preeclampsia and heart failure, fetal morbidity and mortality is also higher, but the newborn itself does not necessarily occur hyperthyroidism. If the mother is treated with iodine for a prolonged period of time, the fetus may develop hypothyroidism or goiter after 10 to 12 weeks of gestational age.