Most women will not be affected by menstruation after the IUD, while some women will have their menstruation affected to different degrees. Some women will experience increased menstruation after the IUD because the IUD is a foreign body, which will stimulate the endometrium after placing it in the uterus, causing the endometrium to shed irregularly, thus increasing menstrual flow; 2. Some women will experience continuous menstrual flow and prolonged menstrual period after the IUD, as the endometrium will shed continuously under the prolonged stimulation of the IUD, resulting in continuous menstrual flow; 3. Clinically, some women will experience low menstrual flow, which may be due to the severe damage to the endometrium after the IUD. Some women may have low menstrual flow after IUD, which may be due to the serious damage to the uterine lining after the IUD is inserted. If a woman has excessive or scanty menstrual flow after IUD application, it may be caused by discomfort with the IUD, and the IUD can be removed if necessary.