Medical Author: Melissa Conrad Stöppler, MD, Chief Medical Editor
Medically Reviewed on 3/11/2019
Doctor's Notes on Uterine Fibroids
Uterine fibroids are benign (non-cancerous) tumors of smooth muscle that originate in a woman’s uterus (womb). The medical terms for a fibroid is leiomyoma. The cause of fibroids is not well understood, but they are very common in women of childbearing age.
Fibroids range dramatically in size. They may be microscopic or may be eight or more inches across. Typically they are between the size of a marble and a baseball. Fibroids may occur in clusters. In most cases, fibroids do not have any associated symptoms. However, depending on their size, location within the uterus, and proximity to other pelvic organs, they may cause abnormal vaginal bleeding or heavy menstrual periods, abdominal or pelvic discomfort, frequent urination, or a feeling of pressure in the lower abdomen.Endometriosis : Test Your Medical IQ Quiz

Endometriosis occurs deep inside the uterus.
See AnswerREFERENCE:
Kasper, D.L., et al., eds. Harrison's Principles of Internal Medicine, 19th Ed. United States: McGraw-Hill Education, 2015.