After more than a year of menopause, menstruation may be a normal phenomenon, or it may be caused by pathologic factors such as endometrial lesions, vaginitis, birth control ring damage, uterine fibroids and other causes of abnormal vaginal bleeding. 1. Normal phenomenon: If a woman of childbearing age stops menstruating for more than a year and then menstruates again, it may be the result of taking medication to regulate menstruation. If the ovaries of menopausal women still have a small amount of hormone secretion, menstruation may also occur more than a year after menopause, which is usually a normal phenomenon. 2. Pathological factors (1) Endometrial lesions: such as endometrial inflammation, polyps and endometrial cancer, etc. can cause abnormal vaginal bleeding after menopause, which will make the patient realize that menstruation will come back after more than one year. (2) Vaginitis: After menopause, the vaginal mucosa and endometrium show progressive atrophy, causing senile vaginitis, which leads to abnormal vaginal bleeding, which is mistaken as menstruation, thus giving the false impression of menstruation after menopause. (3) Injury of birth control ring: If you wear a birth control ring and have not taken it out after menopause, with the atrophy of the uterus, the ring can affect the uterine cavity and cause intrauterine bleeding, which may cause the illusion of menstruation after menopause for more than a year. (4) Uterine fibroids: also known as fibroids, with uterine bleeding, miscarriage, infertility and other main symptoms, may be manifested as the illusion of menstruation after more than a year of menopause, but in fact, abnormal vaginal bleeding. If menstruation comes back after a year or so, it is recommended to go to the hospital in time to find out whether the so-called menstruation is abnormal vaginal bleeding, and then treat it actively after a clear diagnosis so as to avoid delaying the condition.