Important tests during pregnancy are blood HCG and ultrasound to determine early intrauterine pregnancy, initial screening for high-risk pregnancies and underlying diseases, NT, open neural tube malformations and chromosomal aneuploidies of the fetus, fetal ultrasound screening, screening for malformations and indicators of fetal growth and development, and prevention of various complications during pregnancy. Early pregnancy, middle pregnancy and late pregnancy have different focuses. 1. Early pregnancy: the main focus is to determine the basal blood pressure and basal body weight, improve ultrasound and HCG examination to determine early pregnancy, determine the basal blood pressure and basal body weight, but also involves high-risk pregnancies and the initial screening of underlying diseases, early pregnancy maternal serologic screening for fetal aneuploidy abnormalities, and fetal posterior nuchal translucency thickness (NT) screening. Estrogen and progesterone related to preeclampsia are also covered. 2 . Mid trimester: open neural tube malformations and chromosomal aneuploidy anomalies of the fetus, fetal ultrasound screening, screening for malformations and various indices of fetal growth and development including uterine height, abdominal circumference, body weight, and biparietal diameter of the fetus. It also involves the prevention of various complications during pregnancy, including screening for gestational hypertension and gestational diabetes. 3. Late pregnancy: indicators of fetal growth and development, including uterine height, abdominal circumference, weight, fetal biparietal diameter. It is also necessary to pay attention to pregnancy complications, late pregnancy also need to strengthen fetal monitoring, fetal heart monitoring timely detection and correction of intrauterine hypoxia. In addition to the above tests, thyroid function, insulin, adrenocorticotropic hormone, glucagon, etc., will be carried out at different stages of pregnancy to reflect the metabolic level and state of material metabolism of pregnant women. Pregnant women need to follow the doctor’s instructions for the relevant tests to maximize the health of the pregnant woman and her future baby.