Fibroid is a benign tumour of fibrous and muscular tissue, one or more of which may be found in the muscular walls of the uterus (womb). Fibroids often cause pain, excessive menstrual bleeding and they may become quite large. They do cause infertility. Fibroids can be removed surgically, but in some cases, the whole of the uterus is removed (called hysterectomy or uterectomy).