Objective factors for high-risk pregnancies 1. Age of the pregnant mother Pregnant women older than 35 years old are called “advanced pregnant women” and are significantly more likely to have chromosomal birth defects, therefore, it is now recommended that pregnant women over 35 years old undergo prenatal genetic diagnosis during routine prenatal checkups. 2. Weight of pregnant mothers Women who weigh <45 kg during non-pregnancy have an increased risk of delivering small full-term babies. Low-weight women who do not gain enough weight during pregnancy (<7 kg) also increase this risk, with an incidence of 30%, while obese mothers, on the other hand, increase the risk of delivering a large baby or developing gestational diabetes and hypertension. If the mother has had more than one spontaneous miscarriage, premature birth or had a huge baby or stillbirth before this pregnancy, the probability of repeating the above situation in this pregnancy is significantly increased. If the mother or sister of the pregnant mother has had a serious abnormality during the pregnancy, the probability of her mother having an abnormality is also increased. If the woman's blood type is O and the husband's blood type is non-O; or if the woman's blood type is Rh-negative and the husband's blood type is Rh-positive, there will be a mother-infant blood group mismatch, resulting in neonatal hemolytic disease. 4. Pregnant mothers with pregnancy comorbidities Pregnant mothers with pregnancy comorbidities such as heart disease, diabetes, hypertension, kidney disease, hepatitis, hyperthyroidism, etc., active treatment of the original disease is the key and requires multidisciplinary cooperation. Pregnancy can only begin after the primary medical condition is controlled. Close follow-up and regular obstetric examinations are required during pregnancy, and if the condition worsens, it is inappropriate to continue the pregnancy and terminate it at the appropriate time. The doctor will weigh the mode of delivery according to the specific condition, and if these primary conditions are well controlled, vaginal delivery is usually possible. Complications of pregnancy that occur only during pregnancy Hypertensive disorders of pregnancy, intrahepatic cholestasis syndrome during pregnancy and gestational diabetes mellitus are diseases that are specific to pregnancy. Therefore, it can be said that pregnancy complications only occur during pregnancy. 1. Gestational hypertension Gestational hypertension in pregnant mothers is related to age, obesity, genetics, positive anti-cardiolipin antibodies, hypertension and chronic nephritis. Common symptoms are hypertension and proteinuria. Treatment is based on rest, hypotension, antispasmodic and sedation. If the disease continues to progress with active treatment, termination of pregnancy is the only effective treatment. If the disease can be effectively controlled, the mode of delivery should be weighed against the placental function of the pregnant mother. Suggestions: moderate exercise, adequate sleep, proper diet, calcium supplementation and aspirin supplementation before or after pregnancy can prevent this disease in pregnant women with a tendency to hypercoagulability. Intrahepatic cholestasis during pregnancy This disease is related to the high estrogen status of pregnant mothers and occurs mostly in late pregnancy, twin pregnancies, ovarian hyperstimulation and mothers who have used oral contraceptives in the past, with obvious geographical and seasonal differences. In China, it occurs mostly in the Yangtze River basin and is more common in winter. The common symptom is itching without skin damage. The toxicity of bile acids can cause postpartum hemorrhage and fetal distress in pregnant mothers. Suggestions: Pregnant mothers should strengthen fetal monitoring in late pregnancy and take advantage of the timing of termination of pregnancy, which can significantly reduce perinatal mortality. The mode of delivery needs to be decided after taking into account the status of the mother and child. The risk factors for gestational diabetes include obesity, advanced age, abnormal glucose tolerance, polycystic ovary syndrome, and family history of diabetes. A glucose tolerance test is performed in the middle of pregnancy to clarify the diagnosis. Recommendations: Pregnant mothers must pay attention to diet control, moderate exercise is the key to treatment, and if diet cannot be controlled, insulin therapy is required. In conclusion, high-risk pregnancy is closely related to the age, nutritional status, pre-pregnancy weight and the presence of underlying diseases of the pregnant mother. A reasonable diet, balanced nutrition, adequate vitamins and iron, calcium and various trace elements. High-risk pregnancy can be prevented by moderate exercise, adequate sleep, left-sided position, close monitoring of fetal movement and active treatment of primary diseases. High-risk pregnancy is not an absolute indication for cesarean delivery. As for the delivery method, we need to evaluate the condition of the pregnant woman, the condition of the fetus, the function of the placenta and the condition of the cervix.