Endometrial polyps are one of the most common etiologies of abnormal genital bleeding in both premenopausal and postmenopausal women [1-3]. They are hyperplastic overgrowths of endometrial glands and stroma that form a projection from the surface of the endometrium (lining of the uterus). They may also be asymptomatic. The great majority of endometrial polyps are benign, but malignancy occurs in some women .
The epidemiology, diagnosis, and management of endometrial polyps are reviewed here. General principles of the evaluation of uterine bleeding are discussed separately. (See "Approach to abnormal uterine bleeding in nonpregnant reproductive-age women" and "Postmenopausal uterine bleeding".)
Endometrial polyps are localized hyperplastic overgrowths of endometrial glands and stroma around a vascular core that form a sessile or pedunculated projection from the surface of the endometrium (picture 1) [3,4]. Smooth muscle is sometimes present.
Single or multiple polyps may occur and range in diameter from a few millimeters to several centimeters (picture 2) . Polyps can develop anywhere in the uterine cavity.
Several molecular mechanisms have been proposed to play a role in the development of endometrial polyps. These include monoclonal endometrial hyperplasia , overexpression of endometrial aromatase [7,8], and gene mutations [9,10]. Like uterine leiomyomas, polyps have characteristic cytogenetic rearrangements. Rearrangements in the high-mobility group (HMG) family of transcription factors appear to play a pathogenic role [9,11,12].