Pelvic mass without blood flow signal may be uterine fibroids, pelvic inflammatory mass and other reasons, need to be analyzed specifically. 1. Uterine fibroids: uterine fibroids occur in the myometrium, can involve the plasma membrane of the uterus and the endometrium, if the uterine fibroids are necrotic, there is no blood signal, which belongs to a kind of benign lesion. 2. Pelvic inflammatory mass: if there is pelvic inflammatory disease, when the inflammation is more serious, it may cause the pelvic peritoneum to be wrapped around the inflammation, causing wrapped effusion, and at this time there is no blood flow signal. If there is a pelvic mass without blood flow signal, you need to go to the hospital in time, under the guidance of the doctor for standardized treatment to promote discomfort relief.