The main side effect of the Mannorrhea ring is a change in bleeding pattern, which manifests itself as spotting, causing a decrease in menstrual flow or even amenorrhea. The Mannorrhea ring is an intrauterine device with levonorgestrel, which can slowly release progesterone in the uterine cavity for 3-5 years and is placed for five years, and a tail filament. In clinical practice, the IUD is mainly used to treat excessive menstruation due to adenomyosis, dysmenorrhea, or other functional pathologies that cause heavy menstruation. After use, the menstrual flow may decrease or even become amenorrheic, but will return to normal after the IUD is removed. The main effect of the IUD is to change the endometrium of the uterus, which is not conducive to the fertilization of the egg, and to thicken the cervical mucus, which is not conducive to sperm penetration.