What are the diagnostic steps and treatment options for abnormal heavy menstrual bleeding?

Differential Diagnosis for Abnormal Heavy Menstrual Bleeding

The differential diagnosis for abnormal heavy menstrual bleeding is systematically organized using the PALM-COEIN classification system, which divides causes into structural (PALM) and non-structural (COEIN) etiologies. 1

Structural Causes (PALM)

Structural abnormalities can be diagnosed with imaging and include:

• Polyp - Endometrial polyps are common structural sources of abnormal uterine bleeding, particularly in women over 40 years of age 2
• Adenomyosis - A frequent cause in premenopausal women that can be visualized on imaging 2
• Leiomyoma - Uterine fibroids are the most common structural cause in women under 40 years of age presenting with heavy menstrual bleeding 2
• Malignancy and hyperplasia - Endometrial cancer is the most serious etiology and the main focus in postmenopausal women with bleeding; endometrial hyperplasia is also included in this category 2

Non-Structural Causes (COEIN)

Non-structural causes cannot be assessed with imaging but are critical to identify:

• Coagulopathy - Bleeding disorders affect approximately 90% of women with underlying coagulation defects; von Willebrand disease is the most common inherited bleeding disorder causing heavy menstrual bleeding 3, 4
• Ovulatory dysfunction - Chronic anovulation leads to irregular bleeding and prolonged unopposed estrogen stimulation; causes include polycystic ovary syndrome, uncontrolled diabetes mellitus, thyroid dysfunction, hyperprolactinemia, and use of antipsychotics or antiepileptics 4
• Endometrial - Primary endometrial disorders such as molecular deficiencies in the regulation of endometrial hemostasis 2
• Iatrogenic - Includes bleeding from exogenous gonadal steroids, intrauterine devices, and anticoagulation therapy (approximately 70% of women on anticoagulation experience heavy menstrual bleeding) 2, 3
• Not yet classified - Other causes not fitting into the above categories 2

Clinical Predictors of Heavy Menstrual Bleeding

Heavy menstrual bleeding can be predicted based on specific clinical features:

• Clots ≥1 inch in diameter 3
• Low ferritin levels indicating iron deficiency 3
• "Flooding" defined as changing a pad or tampon more frequently than hourly 3
• Bleeding that saturates a large pad or tampon hourly for at least 4 hours requires urgent evaluation 5, 1

Red Flags Requiring Specific Evaluation

Certain presentations mandate additional workup:

• Heavy menstrual bleeding with flooding and/or prolonged menses accompanied by personal or family history of bleeding strongly suggests a bleeding disorder and requires hematology referral 3
• Women 35 years or older with recurrent anovulation require endometrial biopsy 4
• Women younger than 35 years with risk factors for endometrial cancer (obesity, diabetes, chronic anovulation) require endometrial biopsy 4
• Excessive bleeding unresponsive to medical therapy warrants endometrial sampling 4