The nature and classification of uterine fibroids (a) Nature: Uterine fibroids are not terrible, it is the most common benign tumor in female reproductive organs. According to the relevant literature, the incidence rate of women over 35 years old is about 40%. Its etiology is unknown, and it is generally believed that the occurrence of uterine fibroids is related to sex hormones. Uterine fibroids are formed by the proliferation of uterine smooth muscle cells and are pathologically characterized by substantial spherical nodules of varying sizes. The tumor is surrounded by a pseudo-envelope made of compressed muscle fibers, and there is loose connective tissue between the pseudo-envelope and the fibroid. (b) Classification According to the site of growth of fibroids, they can be divided into cervical fibroids and uterine body fibroids, with uterine body fibroids being the most common. According to the relationship between fibroids and uterine wall, they can be divided into 3 categories: 1. intermyometrial fibroids: located in the myometrium, surrounded by myometrium; most of the fibroids belong to this category, accounting for 60%-70%; 2. subplasma fibroids: protruding from the plasma surface of uterine body, the surface only covers the plasma membrane, accounting for 20%; 3. submucosal fibroids: fibroids growing into the uterine cavity, the surface covers the uterine mucosa, accounting for 10%-15 1. interstitial leiomyoma protruding into the plasma layer 2. interstitial leiomyoma 3. tipped submucosal leiomyoma 5. tipped subplasma leiomyoma 6. tipped submucosal leiomyoma protruding from the cervix into the vagina 7. submucosal leiomyoma 8. cervical leiomyoma 9. uterine leiomyoma protruding into the broad ligament