There are two types of cases in which the IUD falls off: 1) the position of the IUD has shifted downward; 2) it comes out of the vagina. If the ring comes out of the vagina, there will be no symptoms, and the ring will be gone unconsciously. If the ring moves down, there will be lower abdominal distension, lumbar pain, a small amount of vaginal bleeding, or blood in the leukorrhea. During menstruation, there will be symptoms such as increased bleeding and long menstrual period, and anemia and infections will easily occur. The main reason for the detachment of the birth control ring may be due to the looseness of the cervical opening, the ring does not match with the uterine cavity, the uterus rejects the foreign body or the menstrual flow of blood and the ring are discharged out of the body together. If the IUD falls off, it loses its contraceptive effect. Women who are worried about the IUD falling off should have regular ultrasound checkups, and if there are any changes in the IUD, they should remedy the situation in time.