What are the guidelines for managing abnormal uterine bleeding (AUB) in adolescents?

Management of Abnormal Uterine Bleeding in Adolescents

The first-line approach to abnormal uterine bleeding (AUB) in adolescents is medical management with hormonal therapy, reserving surgery only for those who fail medical treatment or are hemodynamically unstable. 1

Initial Assessment and Stabilization

Hemodynamic Evaluation

• Assess hemodynamic stability immediately by measuring orthostatic blood pressure and pulse, with urgent evaluation warranted if bleeding saturates a large pad or tampon hourly for ≥4 hours 2, 1
• Check for signs of anemia including pallor, tachycardia, and fatigue 1

Mandatory Exclusions

• Test for pregnancy (β-hCG) in all reproductive-age adolescents regardless of sexual history, as pregnancy complications are critical differential diagnoses 2, 3
• Rule out trauma and sexually transmitted infections through history and examination, even if the patient denies sexual activity 3
• Screen for bleeding disorders, as AUB may be the first presentation of an underlying coagulopathy, particularly when heavy menstrual bleeding occurs at menarche or includes warning signs like bleeding lasting >7 days or blood loss >80 mL per cycle 4, 1, 3

Laboratory Workup

• Complete blood count to assess for anemia from blood loss 1
• Serum ferritin to evaluate iron stores 1
• Thyroid-stimulating hormone and prolactin levels to exclude endocrine causes 2, 5
• If bleeding disorder suspected, coordinate with hematology for coagulation studies including von Willebrand factor, factor VIII, and platelet function testing 1

Understanding the Etiology

Most Common Cause in Adolescents

Anovulation due to hypothalamic-pituitary-ovarian axis immaturity is the most common cause of AUB in adolescents, particularly in the first 2-3 years post-menarche 6, 3. This represents dysfunctional uterine bleeding (DUB) after excluding other pathologic causes 6.

PALM-COEIN Classification

Use the FIGO classification system to systematically evaluate causes 5, 7:

• Structural (PALM): Polyps, Adenomyosis, Leiomyoma, Malignancy/hyperplasia 7
• Non-structural (COEIN): Coagulopathy, Ovulatory dysfunction, Endometrial disorders, Iatrogenic, Not yet classified 7

Imaging Approach

First-Line Imaging

• Combined transabdominal and transvaginal ultrasound with Doppler is the initial imaging study of choice to identify structural causes such as polyps, adenomyosis, leiomyomas, and endometrial pathology 2, 5
• Transvaginal approach provides superior spatial and contrast resolution, while transabdominal imaging is helpful for significantly enlarged uteri 8

Advanced Imaging

• Consider saline infusion sonohysterography when structural abnormalities need further characterization, as it has 96-100% sensitivity for uterine pathology 2, 5
• MRI pelvis should be used when ultrasound incompletely visualizes the uterus or findings are indeterminate 2, 5

Medical Management Algorithm

Acute Heavy Bleeding (Hemodynamically Stable)

For acute bleeding, use high-dose combined oral contraceptives (COCs) as first-line therapy 3, 9:

• Monophasic COC containing 30-35 mcg ethinyl estradiol: 1 pill three times daily until bleeding stops (usually 24-48 hours), then taper to once daily 9
• Continue for at least 3 months to allow cycle regulation 9

Alternative acute management options 1, 9:

• Tranexamic acid 1300 mg orally three times daily or intravenous form for rapid hemostasis 1
• Aminocaproic acid (oral or intravenous) as an antifibrinolytic agent 1

Acute Heavy Bleeding (Hemodynamically Unstable)

For hemodynamically unstable patients 1, 9:

• Intravenous conjugated estrogen 25 mg every 4-6 hours (maximum 4 doses) until bleeding slows 9
• Simultaneously begin high-dose oral COCs as above 9
• Consider blood transfusion if hemoglobin <7 g/dL or symptomatic anemia 1
• Reserve surgical interventions (dilation and curettage, examination under anesthesia) only for patients who fail medical therapy or remain clinically unstable despite initial measures 1

Maintenance Therapy After Acute Episode

Once acute bleeding is controlled, transition to maintenance hormonal therapy 1:

First-line options 6, 1, 9:

• Combined oral contraceptives (standard dosing: 1 pill daily) - most commonly used 6, 9
• Levonorgestrel-releasing intrauterine device - considered first-line for heavy menstrual bleeding, especially when contraception is also needed 9
• Oral progestins (medroxyprogesterone acetate 10 mg daily for 10-14 days per month) 6, 1
• Injectable progestins (depot medroxyprogesterone acetate) 1

Non-hormonal options 6:

• NSAIDs (ibuprofen, naproxen) - reduce bleeding by 20-50% in ovulatory menorrhagia 5, 6
• Tranexamic acid - effective non-hormonal alternative 6

Treatment Selection Based on Severity

For mild AUB: Observation may be sufficient, with reassurance and menstrual calendar tracking 3

For moderate AUB: Standard-dose COCs or cyclic progestins 6, 3

For severe/life-threatening AUB: High-dose COCs, intravenous estrogen, and/or interventional procedures as outlined above 3

Special Considerations for Adolescents

Bleeding Disorders

• Up to 20% of adolescents with heavy menstrual bleeding at menarche have an underlying bleeding disorder, most commonly von Willebrand disease 1
• Work in coordination with hematology for evaluation and management 1
• Counsel patients with bleeding disorders about safe medication use (avoid NSAIDs and antiplatelet agents) and future surgical considerations 1

Fertility Preservation

• Maintenance of fertility is of critical importance in adolescents, making invasive measures a last resort 4
• Avoid endometrial ablation and hysterectomy except in extreme circumstances 4

Quality of Life Impact

• AUB significantly affects adolescents' physical, social, emotional, and material quality of life 1, 9
• Address school absences, activity limitations, and psychosocial concerns 9

When to Refer to Gynecology

Refer to gynecology when 5:

• Medical management fails after 3-6 months of appropriate therapy 5
• Structural abnormalities requiring surgical intervention are identified 5
• Endometrial sampling shows hyperplasia or malignancy (rare in adolescents) 5
• Patient remains hemodynamically unstable despite medical management 1

Common Pitfalls to Avoid

• Never assume sexual inactivity - always test for pregnancy and STIs regardless of history 3
• Do not overlook bleeding disorders - screen carefully, especially when bleeding occurs at menarche or is severe 1, 3
• Avoid NSAIDs in patients with cardiovascular disease due to MI risk, and avoid tranexamic acid due to thrombosis risk 2
• Do not use unopposed estrogen long-term - always transition to combined hormonal therapy or add progestin 9
• Recognize that abnormal bleeding with progestin-only contraceptives (like implants) is common and may require additional management, though it can also indicate STI 8