Uterine fibroids are broadly classified into 3 types according to their growth sites: submucosal fibroids, interstitial fibroids and subplasma fibroids. The fibroids that affect the morphology of the uterine cavity are mainly submucosal fibroids and intramural convex fibroids. The clinical symptoms of fibroids depend on the location, size, growth rate, and the presence of complications of fibroids. The main clinical manifestations are (1) Menstrual changes: It is the most common symptom of fibroids. It is mainly seen in larger interstitial myoma and submucosal myoma, while subplasmalemma myoma rarely causes menstrual changes. The symptoms are increased menstrual flow and prolonged menstrual period. The causes are: (1) the increase of the endometrial area; (2) interstitial myoma affecting the contraction of the smooth muscle of the uterus; (3) endometrial microvascular changes; (4) combined with endometrial polyps and endometrial hyperplasia, etc. (2) Lower abdominal mass and compression symptoms: When the uterus is enlarged beyond 12 weeks of gestation, or when the subplasma myoma is located at the base of the uterus, a hard mass can be palpated in the middle of the lower abdomen, more easily when the bladder is full. As the fibroid increases in size, it may compress the adjacent organs and cause symptoms. For example, anterior wall leiomyosarcoma compressing bladder may cause frequent and urgent urination; cervical leiomyosarcoma compressing bladder triangle may cause dyspareunia and even urinary retention; posterior wall leiomyosarcoma compressing rectum may cause dyspareunia and discomfort after defecation; broad ligament leiomyosarcoma compressing ureter may even cause hydronephrosis; (3) increased leucorrhea: leiomyosarcoma increases the area of endometrium of uterine cavity, increases glandular secretion and pelvic congestion, resulting in increased leucorrhea. Submucosal leiomyoma combined with infection may lead to purulent leucorrhea; (4) pain: leiomyoma usually does not cause pain. (4) Pain: fibroids usually do not cause pain, but when they increase in size and compress pelvic organs, blood vessels and nerves, they may cause lower abdominal distension or vague pain; torsion of leiomyosarcoma or redness of leiomyosarcoma may cause acute abdominal pain; submucosal fibroids may stimulate uterine contraction and cause spasmodic pain. (5) Infertility and miscarriage: fibroids can cause infertility and increase the incidence of miscarriage and preterm delivery. The effect on conception and pregnancy outcome may be related to the location and size of the fibroid. Large interstitial fibroids located in the horn of the uterus may affect the patency of the fallopian tubes, and submucosal fibroids may affect the fertilization of the egg; (6) Anemia: Prolonged excessive menstruation or irregular vaginal bleeding may cause secondary anemia. More severe anemia is seen in patients with submucosal fibroids. Submucosal fibroids may protrude wholly or partially into the uterine cavity. The sonogram shows a round mass with a perithelium that is partially covered by the endometrium on the surface of the uterine cavity. The endometrium is mostly interrupted at the base of the fibroid, while the perithelium on the surface continues with the endometrium and the tip or base is mostly wide. Larger submucosal fibroids may form a tipped submucosal fibroid and may reach down into the cervical canal or even outside the cervical canal, forming a tipped submucosal fibroid that prolapses into the vagina, with only a band of hypoechogenicity detectable in the uterine cavity on 2D ultrasound images. For this type of fibroid, color Doppler can help improve the diagnosis. In type I, the myoma is partially protruding into the uterine cavity from the intermyometrial wall, the uterine body is normal or slightly larger, the endometrial baseline is elevated and distorted, and the endometrial layer is compressed. The CDFI shows circumferential blood flow, stellate blood flow or blood flow from the base of the tumor in the myometrium; type III is a type with ectopic prolapse, where the echogenicity of the uterine wall is still homogeneous and a hypoechoic band is visible in the uterine cavity, starting from the uterine cavity and extending into the cervix or even the vagina, and the cervical canal may be dilated, and the prolapse is a substantial hypoechoic or moderate hypoechoic mass. CDFI shows a strip of arteriovenous blood flow in the uterine cavity, which extends to the cervical or vaginal tumor.