Umbilical cord blood flow refers to the blood flow in the umbilical cord of the fetus, which can reflect the blood supply and oxygenation of the fetus in the uterus, and help to assess the growth and development of the fetus in the uterus. The umbilical cord is the connection between the mother and the fetus, and is mainly composed of the umbilical vein and the umbilical artery. The blood flowing inside the vein is arterial blood, which is rich in oxygen and nutrients and can provide the material basis for fetal development. The venous blood flowing in the arteries carries the metabolites of the fetus so that they can be excreted through the veins of the mother. The blood supply to the fetus in the uterine cavity can be monitored during pregnancy by ultrasound detection of umbilical cord blood flow. There are standardized values for umbilical cord blood flow at each gestational week. If the test results are not within the standard range, abnormal fetal development should be considered and further testing is required. In case of abnormal umbilical cord blood flow, appropriate treatment should be carried out under the guidance of the doctor to improve the development of the fetus.