The causes of delayed menstruation with IUD include pregnancy with IUD, uterine cavity lesions, endocrine abnormalities, etc. 1.Pregnancy with IUD: If the IUD moves down or the size of the IUD is not suitable, the IUD cannot play the contraceptive effect normally and women may become pregnant, which may cause delayed menstruation; 2.Uterine cavity lesion: The IUD needs to enter the uterine cavity through the vagina for surgical operation, and the aseptic operation is not strict or friction occurs after the IUD is placed, which may stimulate inflammation of the endometrium and cause inflammation of the endometrium or cervical canal, resulting in local adhesions and retention of menstrual blood. 3.Endocrine abnormalities: Some women feel nervous or psychologically stressed about the operation of the uterine cavity, which can lead to endocrine changes and abnormal hormone secretion, resulting in delayed menstruation; 4.Other conditions: Some patients have dysfunctional uterine bleeding or adenomyosis, accompanied by bleeding and abdominal pain. In the case of this condition, the Manned Ring can be placed to reduce or postpone the menstrual flow in order to relieve the symptoms.