Classification is based upon the position of the fibriod within the uterus.
They result in uniform enlargement of the uterus but may also cause irregular distention. They cause indentation of the uterine cavity. The uterus may then contract causing the fibroid to be expelled from the uterine wall and becoming a fibroid polyp. These fibroids project from the peritoneal surface of the uterus. They range from small nodules on the surface to large masses weighing up to 20kg.