Uterine fibroids (also referred to as myomas, leiomyomas, leiomyomata, and fibromyomas) are non-cancerous (benign) tumors that grow within the muscle tissue of the uterus. Approximately 20-40% of women 35 years and older have fibroids. While many women with fibroids do not experience any symptoms, the location and size of fibroids can cause symptoms that can affect a woman's quality of life.