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Abnormal Uterine Bleeding

By Barb Dehn, RN, MS, NP, FAANP, NCMP

It’s estimated that 1.4 million US women will experience abnormal uterine bleeding (AUB) each year. This includes an estimated 50% of women in perimenopause, who have an increased incidence of polyps, fibroids and anovulation which leads to their AUB. (1, 2)  In addition, over half of women with heavy menstrual bleeding report that their periods interfere with their lives compared to women with lighter cycles. (2)

(Sources: 1. Davidson, BR, et al. Abnormal Uterine Bleeding during the reproductive years. J Midwifery Womens Health. 2012 May-June 57 (3);248-254. 2. Brito LGO, Panobianco MS, Sabino-de-Freitas MM, et al. Uterine leiomyoma: Understanding the impact of symptoms on women’s lives. Reprod Health. 2014:11:10. )


The American Congress of Obstetricians and Gynecologists (ACOG) defines Abnormal Uterine Bleeding this way.

ACOG Definition of Abnormal Uterine Bleeding (AUB)

Bleeding that requires more than 1 pad/hour for more than 1 day
Bleeding for more than 7 days at a time
Bleeding intervals that are less than 20 days apart
Bleeding in excess of 80 cc a month
– a super tampon or pad can hold approximately 10 cc of blood
Bleeding that causes anemia
Bleeding that leads to disruption in life style

Source: ACOG, Committee Opinion. April 2013 (reaffirmed 2015), number 557.

When women present for gynecologic care with a history of abnormal bleeding, providers can now use a new terminology, PALM – COEIN, which was agreed upon by the International Federation of Gynecology and Obstetrics (FIGO). PALM – COEIN uses an acronym to classify and separate the causes of AUB into structural and non-structural etiologies.

Structural causes include polyps, adenomyosis, leiomyoma (fibroids) and malignancy, while non-structural causes includes coagulopathy, ovulatory, endometrial, iatrogenic and non-classified. The PALM-COEIN terminology helps women’s health providers as they consider the differential diagnoses and treatment options based on the specific etiology.




PALM – Structural causes of AUB


P – Polyp

A – Adenomyosis

L – Leiomyoma (fibroids)

M – Malignancy/Hyperplasia


COEIN – Non-structural 


C – Coagulopathy

O – Ovulatory

E – Endometrial

I – Iatrogenic

N –Not Classified


Source: Established by FIGO – Fédération Internationale de Gynécologie et d’Obstétrique (the International Federation of Gynecology and Obstetrics)

When evaluating women with bleeding, one test that’s often overlooked especially in women over 40, is a quantitative pregnancy test, which is one of the most common causes of bleeding in women of reproductive age. Once it’s determined that the woman isn’t pregnant, it’s incumbent to begin to evaluate for structural etiologies utilizing ultrasound, hysteroscopy, Endosee® and other imaging. In addition, performing an endometrial biopsy for any woman with thickened endometrial lining can easily be completed during an office visit.

I hope this has helped with how you might evaluate and assess your patients with Abnormal Uterine Bleeding.



Barb Dehn, RN, MS, NP, FAANP, NCMP will speak at the Nashville CME Event, May 23-26.