After the fertilized egg has been deposited in the uterine lining, the uterus will produce the phenomenon of rejection, so individual women will have the symptom of pain in the abdomen. If the pregnant woman not only has the symptom of hidden pain and discomfort in the abdomen, but also has vaginal bleeding, etc., it is considered to be a pre-eclampsia, which needs to be treated to prevent the occurrence of miscarriage. If there is pain in the lower abdomen at the beginning of pregnancy, you should pay attention to rest and reasonable diet. If there is not only pain in the lower abdomen but also vaginal bleeding after pregnancy, laboratory tests of human chorionic gonadotropin and progesterone are needed, combined with thyroid function tests to evaluate the development of the embryo. If there is hypothyroidism and luteal insufficiency, the symptoms of miscarriage can occur.