The phenomenon of stomach pain in the fourth and a half months of pregnancy is divided into physiological and pathological, if the stomach pain is not particularly serious, but will only show a slight drop or bloating pain phenomenon, belongs to the normal physiological performance. Because the fetus grows faster in the fourth and a half months of pregnancy, the uterus will increase in size and show a slight rupture of the uterine ligament or belly, which will cause stomach pain. Pathological stomach pain is due to inflammatory infection in the pelvic cavity or signs of miscarriage, which will result in more pronounced stomach pain, which can be accurately determined by doing ultrasound, combined with individual clinical manifestations. If it is difficult to identify, it is recommended to seek medical attention.