The main feature of pregnancy care is the requirement for a systematic provision of evidence-based prenatal screening programs at specific times. The schedule of prenatal checkups should be decided according to the purpose of prenatal checkups. I. Frequency of antenatal checkups and gestational weeks Reasonable frequency of antenatal checkups and gestational weeks not only ensure the quality of pregnancy care, but also save health care resources. For uncomplicated pregnant women in developing countries, WHO (2006) suggests that at least 4 antenatal checkups are needed, and the gestational weeks are <16 weeks, 24-28 weeks, 30-32 weeks and 36-38 weeks. According to the current situation of pregnancy health care and the need for prenatal checkup programs in China, the recommended gestational weeks for prenatal checkups in this guideline are: 6-13 weeks +6, 14-19 weeks +6, 20-23 weeks +6, 24-28 weeks, 30-32 weeks, 33-36 weeks, and 37-41 weeks. For those with high risk factors, increase the number of times as appropriate. Second, the content of prenatal examination (a) the first prenatal examination (6 to 13 weeks + 6 weeks of pregnancy) 1, health education and guidance: (1) awareness and prevention of miscarriage. (2) Guidance on nutrition and lifestyle (hygiene, sex life, sports and exercise, traveling, work). (3) Continue folic acid supplementation 0.4 to 0.8 mg/d until the 3rd month of pregnancy, and continue to take multivitamins containing folic acid if available. (4) Avoid contact with toxic and harmful substances (such as radiation, high temperature, lead, mercury, benzene, arsenic, pesticides, etc.), and avoid close contact with pets. (5) Use drugs with caution and avoid drugs that may affect the normal development of the fetus. (6) If necessary, vaccinate against tetanus or influenza during pregnancy. (7) Change bad habits (e.g. smoking, alcoholism, drug abuse, etc.) and lifestyles; avoid high-intensity work, high-noise environments and domestic violence. (8) Maintaining mental health, relieving mental stress, and preventing the occurrence of psychological problems during pregnancy and after delivery. 2. Routine health care: (1) Establish a pregnancy health care manual. (2) Carefully inquire about menstruation, determine the week of pregnancy, and project the expected date of delivery. (3) Assess high-risk factors during pregnancy. Maternal history, especially adverse maternal history such as miscarriage, preterm labor, stillbirth, history of stillbirth, history of reproductive tract surgery, any malformation of the fetus or mental retardation of the young child, pre-pregnancy preparations, family history of the person and his/her spouse and history of hereditary diseases. Pay attention to the presence of pregnancy complications, such as chronic hypertension, heart disease, diabetes mellitus, liver and kidney diseases, systemic lupus erythematosus, blood diseases, neurological and psychiatric disorders, etc., and promptly ask for consultation with relevant disciplines, those who are not suitable to continue the pregnancy should be informed and terminate the pregnancy in a timely manner; for those who continue the pregnancy in high-risk pregnancies, assess whether to refer the patient for consultation. There is no vaginal bleeding in this pregnancy, and there are no factors that may cause malformation. (4) Physical examination. Including measurement of blood pressure, body mass, calculation of BMI; routine gynecological examination (if not done in the first 3 months of pregnancy); fetal heart rate measurement (using Doppler auscultation, around 12 weeks of pregnancy). 3. Required items: (1) blood test; (2) urine test; (3) blood type (ABO and Rh); (4) liver function; (5) kidney function; (6) fasting blood glucose; (7) HBsAg; (8) syphilis spirochetes; (9) HIV screening. (Note: Items that have been checked within 6 months before pregnancy can be checked without repeating). 4. Preparatory items: (1) Hepatitis C virus (HCV) screening. (2) Anti-D titer test (Rh negative). (3)75g OGTT (high risk pregnant women or those with symptoms). (4)Thalassemia screening (Guangdong, Guangxi, Hainan, Hunan, Hubei, Sichuan and Chongqing). (5) Thyroid function test. (6)Serum ferritin (for those with hemoglobin <105g/L) test. (7) Tuberculin (PPD) test (high-risk pregnant women). (8)Cervical cytology (those who have not been examined within 12 months before pregnancy). (9) Cervical secretion test for gonococcus and Chlamydia trachomatis (high-risk pregnant women or those with symptoms). (10) Testing for bacterial vaginosis (BV) (for those with a history of preterm labor). (11) Maternal serologic screening in early pregnancy for fetal chromosomal aneuploidy abnormalities [pregnancy-associated plasma protein A (PAPP-A) and free β-hCG, 10-13 weeks of gestation + 6. Precautions: fasting; ultrasonography to determine gestational week; and determination of body mass on the day of blood draw. In high-risk individuals, consider chorionic villus biopsy or combined mid-trimester serologic screening results before deciding on amniocentesis. (12) Ultrasonography. Ultrasonography is performed in early pregnancy: to determine intrauterine gestation and gestational week, fetal viability, number of fetuses or nature of twin chorionic villi, and uterine adnexa. Measurement of fetal posterior nuchal translucency (NT) by ultrasonography at 11-13 weeks +6 ultrasound; approved gestational weeks. NT measurement was performed according to the British Fetal Medicine Foundation standards]. (13)Chorionic villus biopsy (10 to 12 weeks of gestation, mainly for high-risk pregnant women). (14) Electrocardiogram. (II) 14～19 weeks of gestation +6 prenatal checkups 1. Health education and guidance: (1) Awareness and prevention of miscarriage. (2) Knowledge of pregnancy physiology. (3) Guidance on nutrition and lifestyle. (4) Significance of screening for fetal chromosomal aneuploidy abnormalities in the middle trimester. (5) Hemoglobin <105 g/L, serum ferritin <12 μg/L, supplementation of elemental iron 60-100 mg/d. (6) Beginning of calcium supplementation, 600 mg/d. 2. Routine health care: (1) Analyze the results of the first prenatal examination. (2) Ask about vaginal bleeding, diet and exercise. (3) Physical examination, including blood pressure and body mass, to assess whether the growth of pregnant women's body mass is reasonable; uterine fundal height and abdominal circumference, to assess whether the growth of fetus's body mass is reasonable; and determination of fetal heart rate. 3. Required items: None. 4. Preparatory items: (1) Maternal serologic screening in mid-trimester for fetal chromosomal aneuploidy anomalies (15-20 weeks of gestation, optimal gestational week for testing is 16-18 weeks). Precautions: Same as early pregnancy serologic screening. (2) Amniocentesis for fetal karyotyping (16 to 21 weeks of gestation; for pregnant women ≥35 years of age at the time of expected delivery or for high-risk groups).