Heparin injections in late pregnancy will not reach the baby as long as they are given correctly. Heparin is usually injected into the subcutaneous tissue as long as it is injected correctly, it is usually not injected into the abdominal cavity or into the uterus. Therefore, it will not hit the baby. The occurrence of certain diseases during pregnancy is related to thrombosis of veins and micro-veins, poor microcirculation, etc. Appropriate use of heparin can improve microcirculation, which can be used to treat the disease or control the symptoms. Heparin has an anticoagulant effect, and should not be used in the case of bleeding in late pregnancy, which may lead to an increase in the amount of bleeding, causing anemia, and even the possibility of preterm delivery. Therefore, the use of heparin in late pregnancy needs to be strictly controlled under the guidance of the doctor’s indications, and should not be used indiscriminately. And the injection should also be standardized by nurses so that the fetus will not be injured.