conditions people with a uterus can experience. And by talking about uterine fibroids celebrities are helping to raise awareness. Also called leiomyomas or myomas, uterine fibroids are non-cancerous tumors that grow outside the uterus, in the uterine cavity, or within the walls of the uterus. The majority of women deal with them at some point: of people with a uterus develop fibroids by age 50, according to the Mayo Clinic.