A cyst inside the uterus is not serious. It usually refers to a cervical cyst, which is a manifestation of chronic cervicitis. In the process of cervical erosion, the cervical glands, ducts or the mouth of the ducts are covered by squamous epithelium; or due to the proliferation of connective tissue around the mouth of the ducts, the ducts are narrowed or blocked and the glandular secretions cannot be discharged and are retained, forming retention cysts of varying sizes. The small ones are like rice grains and the large ones are like soybeans, greenish-white and contain colorless mucus. If the cyst is infected, it can appear as a small white or yellowish cyst. Cervical cysts, in general, still have a very low rate of malignant change. Small cervical cysts do not require special treatment; if the size of the cyst is large, it can be removed by minor surgery.