Early pregnancy blood values, which refer to HCG, may be caused by ectopic pregnancy, biochemical pregnancy, or embryonic development arrest. 1. Ectopic pregnancy: the embryo is deposited outside the uterine cavity, most often in the fallopian tube, because this is not conducive to the development of the embryo, so the HCG secretion is low, and there may be a drop instead of rise in blood values. 2. Biochemical pregnancy: Biochemical pregnancy is a phenomenon in which the embryo is expelled from the body after the sperm-egg union does not implant in the uterus, which is also known as hidden abortion, and in the case of biochemical pregnancy, the blood value will have a downward trend, which leads to the blood value of the early pregnancy to fall instead of rise. 3. Cessation of embryonic development: If the blood value does not increase but decreases in early pregnancy after observation and continuous testing, then the embryonic development may have ceased, and there may also be symptoms of abdominal pain. In the early stages of pregnancy, it is recommended that pregnant women should listen to the doctor’s instructions to conduct regular checkups, so as to observe the specific conditions of the fetus.