What is the initial treatment for acute abnormal uterine bleeding (aUB)?

Initial Treatment for Acute Abnormal Uterine Bleeding

For acute abnormal uterine bleeding (aUB), the initial treatment depends on hemodynamic stability: hemodynamically unstable patients require emergency interventions including uterine tamponade, intravenous estrogen, dilation and curettage, or uterine artery embolization, while hemodynamically stable patients should receive high-dose oral estrogen, high-dose combined oral contraceptives (3 times daily), oral progestins, or intravenous tranexamic acid as first-line medical management. 1

Emergency Assessment and Stabilization

Immediate hemodynamic assessment is critical. Urgent evaluation is warranted for patients with bleeding that saturates a large pad or tampon hourly for at least 4 hours. 2 All reproductive-age women must have pregnancy testing (β-hCG) performed immediately, as pregnancy-related bleeding requires entirely different management. 2, 3

For Hemodynamically Unstable Patients

Emergency interventions include: 1

• Uterine tamponade (balloon catheter placement)
• Intravenous estrogen (high-dose conjugated estrogen 25 mg IV every 4-6 hours)
• Dilation and curettage (D&C) for patients with acute bleeding resulting in hypovolemia 4
• Uterine artery embolization (interventional radiology procedure)

Medical Management for Hemodynamically Stable Patients

Acute Phase Treatment Options

High-dose hormonal therapy is the cornerstone of acute management. 5, 1 The following regimens are equally effective:

• High-dose combined oral contraceptives: Administer 3 times daily until bleeding stops (typically 24-48 hours), then taper to once daily for 21 days 1
• Intravenous conjugated estrogen: 25 mg IV every 4-6 hours until bleeding stops 5
• Oral estrogen: High-dose oral estrogen is best for controlling acute bleeding episodes 4
• Multidose progestin-only regimen: Medroxyprogesterone acetate 20 mg three times daily 5
• Intravenous tranexamic acid: 10 mg/kg (maximum 600 mg) IV every 6-8 hours 1

Critical Contraindications

In patients with cardiovascular disease or post-SCAD (spontaneous coronary artery dissection), avoid NSAIDs and tranexamic acid due to MI and thrombosis risk. 2, 3 For these patients, progestin-only methods or the levonorgestrel-releasing IUD become preferred options. 3

For patients on antiplatelet therapy, reassess the indication for ongoing antiplatelet therapy and discontinue if appropriate before initiating treatment. 2 Progestin-eluting IUDs are preferred due to minimal systemic absorption. 3

Transition to Long-Term Management

Once acute bleeding is controlled, transition to maintenance therapy is essential to prevent recurrence. The most effective long-term medical treatment is the levonorgestrel-releasing intrauterine system (LNG-IUD), which reduces menstrual blood loss by 71-95% with efficacy comparable to endometrial ablation. 3, 1

Other long-term options include: 1

• Combined oral contraceptives (standard dosing)
• Oral progestins (medroxyprogesterone acetate 10 days per month)
• Oral tranexamic acid (1300 mg three times daily during menses)
• NSAIDs (if no cardiovascular contraindications)

Diagnostic Workup During Stabilization

While initiating treatment, obtain: 2, 3

• Pregnancy test (β-hCG)
• Complete blood count with platelets (assess anemia and coagulopathy)
• Thyroid-stimulating hormone and prolactin levels
• Combined transabdominal and transvaginal ultrasound with Doppler (first-line imaging to identify structural causes)

When to Escalate Care

Refer to gynecology if: 2

• Medical management fails
• Endometrial sampling shows hyperplasia or malignancy
• Postmenopausal bleeding with endometrial thickness ≥4 mm
• Hemodynamic instability persists despite initial interventions

Hysterectomy is the definitive treatment when medical management fails or is contraindicated, particularly for patients who have completed childbearing. 3, 1

Common Pitfalls

Do not delay treatment while awaiting complete diagnostic workup in acute bleeding scenarios—stabilization takes priority. 1 However, ensure pregnancy testing is performed before administering any hormonal therapy. 2

Avoid using endometrial biopsy alone to rule out focal lesions, as it has variable sensitivity; saline infusion sonohysterography has superior sensitivity (96-100%) and negative predictive value (94-100%) for detecting structural pathology. 2, 3