The Mannuelle, also known as the Mannuelle Ring, is a levonorgestrel intrauterine extended-release system that must be removed after 5 years, having reached its expiration date, and continued use will affect the effectiveness of contraception. Levonorgestrel intrauterine extended-release system, which contains levonorgestrel will be released slowly, can prevent sperm through the cervical canal into the uterine cavity, and oocytes combined, so that the fertilized egg can not be able to bed and achieve the effect of contraception. The levonorgestrel intrauterine system needs to be taken out after 5 years. After 5 years of placement, levonorgestrel has been completely released, and even if it is not taken out, there is no drug to continue to act on the lining of the uterus, and the contraceptive effect cannot be achieved. The levonorgestrel intrauterine extended-release system has a tail filament, which stays outside the cervix after the IUD is placed, so if you need to continue contraception after removing the IUD, you can place it again.