How can I differentiate between menorrhagia due to uterine pathology and other causes?

To differentiate menorrhagia caused by uterine pathology from menorrhagia due to other causes, a thorough clinical assessment is essential.

• History: Take a detailed history focusing on the nature of bleeding, presence of related symptoms such as persistent intermenstrual bleeding, pelvic pain, or pressure symptoms, which may suggest uterine cavity abnormalities, fibroids, adenomyosis, or endometrial pathology. Also assess the impact on quality of life and any comorbidities or previous treatments ².
• Physical examination: Perform a pelvic examination if the history suggests related symptoms. Look for a palpable pelvic or abdominal mass, uterine enlargement or tenderness, or signs suggestive of fibroids or adenomyosis. If a pelvic mass is found that is not obviously due to fibroids, or if there are features suggestive of cancer, urgent referral is indicated ¹,².
• Laboratory tests: Conduct a full blood count to assess for anaemia. Consider coagulation studies if there is a personal or family history of bleeding disorders. Routine hormone or thyroid testing is not recommended unless clinically indicated ².
• Imaging and further investigations: Use pelvic ultrasound (preferably transvaginal) to identify fibroids, adenomyosis, or other uterine abnormalities. Transvaginal ultrasound is preferred for suspected adenomyosis, especially if there is significant dysmenorrhoea or a bulky, tender uterus ².
• Hysteroscopy: Offer outpatient hysteroscopy if history suggests submucosal fibroids, polyps, or endometrial pathology, especially with persistent intermenstrual bleeding or risk factors for endometrial pathology. Endometrial biopsy should be done during hysteroscopy if indicated, but blind biopsy is not recommended ².
• Referral: Refer urgently if cancer is suspected or if there is a pelvic mass with other cancer features. Consider specialist referral if menorrhagia is severe, unresponsive to treatment, or if fibroids ≥3 cm are present ¹,².

In summary, menorrhagia caused by uterine pathology is suggested by associated symptoms (pain, pressure, intermenstrual bleeding), physical findings (pelvic mass, uterine enlargement), and imaging or hysteroscopic findings of fibroids, adenomyosis, polyps, or endometrial abnormalities. Menorrhagia without these features is more likely due to other causes and may be managed initially with pharmacological treatment without extensive investigation ¹,².