IUD is the most commonly used contraceptive measure for women of childbearing age, usually for more than 10 years. The reason for menstrual pain after IUD is that the IUD, as a foreign body, placed in the uterine cavity, will cause aseptic inflammation, and it will take a period of time to get used to it. If there is slight abdominal pain or lumbar pain during menstruation, it is a normal phenomenon; if the menstrual flow is more than normal or the pain worsens during menstruation, it is necessary to go to the hospital in time for consultation and treatment; if there is stomach pain after the IUD, or if there is a strange odor in the menstruation, it is necessary to pay attention to whether it is due to the infection caused by the IUD, so it is necessary to go to the hospital for examination and treatment. In fact, there are more harms caused by stomach pain after IUD, for example, it will affect study and work, and also cause gynecological diseases, so you should go to the hospital regularly for rechecking after IUD, so as to avoid any adverse reactions.