How should I evaluate and manage a 12‑year‑old girl with heavy menstrual bleeding (menorrhagia)?

Management of Heavy Menstrual Bleeding in a 12-Year-Old

Begin immediate evaluation for bleeding disorders—specifically von Willebrand disease and platelet function defects—while simultaneously initiating medical management, as up to 20% of adolescents with heavy menstrual bleeding have an underlying coagulopathy that standard coagulation tests will miss. 1, 2, 3

Immediate Diagnostic Evaluation

Critical Laboratory Testing

Order specialized bleeding disorder testing immediately, not just routine coagulation studies:

• Complete blood count with peripheral smear to assess for anemia and thrombocytopenia 2, 4
• Serum ferritin to evaluate iron stores 4
• VWD-specific panel: VWF antigen (VWF:Ag), VWF ristocetin cofactor activity (VWF:RCo), and Factor VIII coagulant activity (FVIII:C) 1
• Platelet function studies if VWD testing is normal but clinical suspicion remains 1

Do not rely on PT/aPTT alone—these standard tests do not detect VWD, Factor XIII deficiency, or platelet function disorders, which are the most likely diagnoses in adolescent menorrhagia. 1 This is the most common diagnostic error in this population. 1

Clinical Assessment Tools

• Pictorial Bleeding Assessment Chart (PBAC) score to objectively quantify menstrual blood loss; a score >100 increases diagnostic sensitivity to 95% 1, 2
• Document associated bleeding symptoms: easy bruising, epistaxis, gingival bleeding, and family history of bleeding disorders 2, 5

Why This Matters

Von Willebrand disease is the most common inherited bleeding disorder (prevalence approximately 1 in 1000), and its incidence in adolescents with heavy menstrual bleeding ranges from 13-20%. 1, 3, 5 Normal platelet count does not rule out qualitative platelet defects. 1

First-Line Medical Management

For Acute Bleeding Control

Tranexamic acid is the preferred first-line non-hormonal agent, reducing menstrual blood loss by up to 50%. 1, 2

• Dosing: 1300 mg orally three times daily during menstruation (typically 5 days) 2
• Particularly useful as it works regardless of underlying etiology 2

Alternative First-Line Options

NSAIDs (mefenamic acid or naproxen) during menstruation only (5-7 days of treatment) 2

• Reduce prostaglandin-mediated bleeding
• Use with caution if bleeding disorder suspected

Hormonal Therapy Considerations

Reserve combined oral contraceptive pills for cases where first-line medical management fails or when maintenance therapy is needed after acute control. 2

• For acute severe bleeding: high-dose estrogen therapy may be necessary 2, 6
• For maintenance: combined oral contraceptives provide excellent cycle control 2

The 52-mg levonorgestrel intrauterine device has superior efficacy for heavy menstrual bleeding and is safe in adolescents with bleeding disorders. 1, 3, 7

Hematology Referral—When and Why

Refer immediately to hematology if:

• Hemoglobin <10 g/dL or signs of hemodynamic instability 4
• Platelet count <150,000/μL (thrombocytopenia found in 13% of cases) 5
• Positive family history of bleeding disorders 5
• No response to initial medical therapy within 48 hours 6
• Any abnormality on specialized VWD or platelet function testing 1

Hematology consultation is mandatory for interpretation of specialized testing, coordination of desmopressin (DDAVP) trial, or factor replacement therapy if VWD is confirmed. 1

Assessment of Severity

Hemodynamic Evaluation

Check orthostatic blood pressure and pulse measurements to assess hemodynamic stability. 4

Anemia Thresholds

• Hemoglobin <12.0 g/dL: Anemia present (occurs in 50% of cases) 5
• Hemoglobin <5.0 g/dL: Potentially life-threatening anemia requiring transfusion (occurs in 10% of cases) 5

Common Pitfalls to Avoid

1. Do not assume normal PT/aPTT rules out bleeding disorders—this is the single most common diagnostic error 1

2. Do not delay hematology referral while waiting for specialized test results if bleeding is severe 1

3. Do not dismiss heavy bleeding at menarche as "normal anovulation" without excluding bleeding disorders first—while anovulatory cycles from immature hypothalamic-pituitary-ovarian axis are common, bleeding disorders frequently present at menarche 2, 7, 5

4. Do not use prolonged high-dose hormonal therapy without first ruling out coagulopathy—if no response to hormonal therapy within 48 hours, reevaluate for bleeding disorder 6

Context: Anovulation vs. Bleeding Disorder

While anovulatory cycles are the most common cause of heavy menstrual bleeding in adolescents due to immature hypothalamic-pituitary-ovarian axis 2, 7, the critical distinction is that bleeding disorders present at menarche with heavy bleeding from the first period. 7, 5 The 20% prevalence of bleeding disorders in this population mandates systematic evaluation rather than assumption of benign anovulation. 1, 3