<qa>  What is a benign tumor of the uterine muscle in pre-menopausUterine leiomyomata fibroids are a common benign tumor of the uterine muscle in pre-menopausal women that may cause bleeding, pelvic pain and pressure. Because fibroids grow in the presence of estrogen, medical therapies that decrease estrogen levels like Gonadotropin releasing hormone,GnRH analog cause fibroids to shrink and so may relieve symptoms. However, such medication can only be given short-term and has inconvenient side effects such as hot-flashes. Thus, many women with symptomatic fibroids choose to have them removed surgically, either individually or by removing the uterus via hysterectomy. 