In a 39-year-old woman with heavy menstrual bleeding, pelvic pressure, lower-extremity heaviness and edema, and a uterine fibroid on ultrasound, which location is most likely?

Most Likely Fibroid Location: Submucosal

In a 39-year-old woman presenting with heavy menorrhagia, pelvic pressure, and lower extremity symptoms, the fibroid is most likely submucosal (Answer D), as submucosal fibroids are specifically and strongly associated with menorrhagia due to their projection into the uterine cavity and direct effect on the endometrial surface. 1

Clinical Reasoning

Why Submucosal Fibroids Are Most Likely

• Submucosal fibroids have the strongest association with heavy menstrual bleeding among all fibroid locations, causing menorrhagia through multiple mechanisms including enlargement of the uterine cavity, impairment of endometrial blood supply, and endometrial atrophy and ulceration. 1

• Transvaginal ultrasound detects submucosal fibroids with 90% sensitivity and 98% specificity, making this diagnosis highly reliable when ultrasound confirms a fibroid in a patient with menorrhagia. 2, 1

• The combination of heavy menstrual bleeding with bulk symptoms (pelvic pressure and lower extremity edema) is most characteristic of a large submucosal fibroid that both distorts the endometrial cavity and exerts mass effect on surrounding structures. 1

Why Other Locations Are Less Likely

• Intramural fibroids (Option C) cause menorrhagia less frequently than submucosal fibroids, and while they can affect fertility and cause some bleeding when they abut the endometrium, the bleeding is typically less severe than with true submucosal lesions. 2, 1

• Subserosal fibroids (Option B) typically do not cause menorrhagia at all—they are primarily associated with bulk symptoms such as pelvic pressure but have minimal effect on menstrual bleeding patterns. 2, 1

• Cervical fibroids (Option A) are rare, accounting for less than 5% of all uterine fibroids, and more commonly present with dyspareunia, urinary obstruction, or vaginal discharge rather than heavy menstrual bleeding as the primary symptom. 2

Diagnostic Confirmation

• Combined transabdominal and transvaginal ultrasound achieves 90-99% sensitivity for detecting uterine fibroids overall, with transvaginal approach providing superior visualization of submucosal location and cavity distortion. 2, 1

• The ultrasound should explicitly assess whether the fibroid distorts the endometrial cavity—confirmation of cavity distortion indicates submucosal location and directs treatment toward hysteroscopic resection as the preferred approach. 2

Treatment Implications

• Hysteroscopic myomectomy is the preferred intervention for submucosal fibroids in patients wishing to preserve the uterus, as these lesions can be resected via a transcervical, transvaginal route. 1

• Submucosal fibroids have the greatest negative impact on fertility (pregnancy rates only 10%, implantation rates 4.3%) and are associated with increased risks of miscarriage, preterm delivery, and postpartum hemorrhage, making treatment particularly important in reproductive-age women. 2

Common Pitfall to Avoid

Do not assume that all fibroids causing menorrhagia are submucosal—intramural fibroids that contact or distort the endometrium can also cause bleeding, but the severity is typically less pronounced. 2 The key distinguishing feature is that submucosal fibroids project into and distort the uterine cavity, which should be confirmed on imaging before planning hysteroscopic intervention. 2, 1