Some patients with fibroids find out that their ultrasound examination sheet says “fibroid degeneration” and ask their doctor in horror, “What is fibroid degeneration? Is it malignant?” The doctor said, “What is fibroid degeneration? It is important to know that most fibroids are benign and only a very small number of them are malignant. There are various types of fibroid degeneration, including benign changes such as glassy, cystic, fatty, calcified, and red. These changes are degenerative changes (commonly known as aging) of fibroids, and occur mostly when the growth of fibroids is accelerated and the blood supply is insufficient, such as during pregnancy and late menopause, without aggravating the patient’s condition. The first to occur is vitreous degeneration, when the ultrasound reveals that the texture of the fibroid becomes soft and transparent; after that, cystic degeneration may occur, when the glassy fibroid liquefies and forms a cystic cavity, soft as a deflated ball of skin; fatty degeneration occurs after the necrosis or vitreous degeneration of the fibroid, often as a pre-calcification; calcification occurs when the blood circulation of the fibroid is affected and calcified deposits appear, forming a very hard It has no possibility of malignant change. It is worth noting that the majority of red lesions occur during pregnancy. After pregnancy, as the uterus and fetus gradually increase in size, the blood supply to the uterus becomes more and more abundant, so that the fibroids are well nourished and their size increases, and the fibroids become necrotic and bleed due to acute ischemia, resulting in red lesions. Although benign, red lesions are often associated with severe abdominal pain and may induce miscarriage or preterm labor. This kind of degeneration is not common, but women who are pregnant with tumors are reminded to pay attention in the middle of pregnancy, and if they have abdominal pain, they should consider if the tumor is degenerative and give prompt treatment. The chance of fibroids becoming cancerous is less than 0.5%, but for sudden growth of fibroids in a short period of time, accompanied by vaginal bleeding or growth of fibroids instead of shrinking after menopause, it is necessary to be alert.