Abnormal Uterine Bleeding

Basics

Description

  • Formerly termed “dysfunctional uterine bleeding”
  • Abnormal uterine bleeding (AUB) is an alteration in regularity, frequency, duration, or volume of normal menses, or intermenstrual bleeding:
    • Blood loss during normal menses is 5–80 mL
    • Normal interval between menses 24–38 d
    • Normal menses last 2–7 d
  • Most common at menarche and perimenopause
  • Can be divided into acute vs chronic
    • Acute AUB: An episode of excessive bleeding that requires immediate intervention to prevent further blood loss
    • Chronic AUB: AUB present for most of the previous 6 mo

Etiology

  • Related to uterine structural abnormalities (PALM):
    • Polyp
    • Adenomyosis
    • Leiomyoma
    • Malignancy and hyperplasia
  • Unrelated to uterine structural abnormalities (COEIN):
    • Coagulopathy:
      • Bleeding disorder should be suspected if heavy bleeding since menarche, family history, other bleeding, or bruising
    • Ovulatory dysfunction:
      • Polycystic ovarian syndrome (PCOS)
      • Very–low-calorie diets, rapid weight change, intense exercise, anorexia nervosa
      • Psychological stress
      • Obesity
      • Hyperprolactinemia
      • Drugs
      • Hypothyroidism
      • Primary hypothalamic dysfunction
      • Liver and kidney disease
    • Endometrial:
      • Infectious or inflammatory (endometritis, pelvic inflammatory disease [PID])
      • Local endometrial stasis disorders
    • Iatrogenic:
      • Contraception (oral and IUD)
      • Hormone therapy
      • Anticoagulants
    • Not otherwise classified:
      • Cesarean scar defect
      • AVM

Pediatric Considerations

Anovulatory bleeding common in adolescence owing to immaturity of the hypothalamic–pituitary–ovarian axis

Diagnosis

Signs And Symptoms

History

  • AUB is typically painless
  • Gynecologic and obstetric history
  • Bleeding pattern and current episode
  • Medical history guided by PALM-COEIN system

Physical Exam

  • Pallor, tachycardia, hypotension, orthostasis in severe cases
  • Pelvic exam to focus on site of bleeding, uterus size and contour, adnexal mass, or tenderness
  • Evaluate for trauma, foreign bodies
  • Typically mild-to-moderate bleeding on pelvic exam
  • Signs of endocrine disorder:
    • Acne, hirsutism, and obesity suggest PCOS
  • Abdominal exam to palpate for masses
ALERT

Hemodynamic instability secondary to AUB is rare; if such instability is present, consider ectopic pregnancy or other causes of heavy menstrual bleeding

Essential Workup

Urine pregnancy test (UPT)

Diagnostic Tests And Interpretation

Lab

  • Pregnancy test, CBC, PT/PTT, type/screen
  • May send iron studies, TSH, LH, FSH, prolactin, cervical cultures, coagulopathy studies for routine follow-up by primary medical doctor (PMD)/gynecology

Imaging

Pelvic ultrasound may show uterine, tubal, or ovarian abnormality; may be needed to rule out other organic or iatrogenic causes in differential diagnoses

Diagnostic Procedures/Surgery

  • Dilation and curettage (D&C) may be required for heavy bleeding unresponsive to other interventions
  • Refer for endometrial biopsy if >45 yr of age or risk factors

Differential Diagnosis

Organic/Iatrogenic

  • Pregnancy complications:
    • Threatened, incomplete, or spontaneous abortion
    • Ectopic pregnancy
    • Molar pregnancy
  • Infectious:
    • Vaginitis
    • Cervicitis
    • PID
  • Coagulopathies:
    • von Willebrand disease
    • Idiopathic thrombocytopenic purpura
    • Inherited platelet defects
  • Medications:
    • Aspirin
    • Antipsychotics
    • Corticosteroids
    • Hormone replacement
    • Oral contraceptives
    • Selective serotonin reuptake inhibitors
    • Tricyclic antidepressants
    • Warfarin
  • Systemic illness:
    • Adrenal, hepatic, renal, or thyroid dysfunction, diabetes mellitus, other endocrinopathies
  • Anatomic lesions:
    • Endometriosis
    • Endometrial hyperplasia
    • Fibroids
    • Polyps
    • Neoplasm
  • Intrauterine devices
  • Trauma
  • Cancer

Hormone Related

See ovulatory dysfunction etiologies

Treatment

Prehospital

IV crystalloid boluses as needed for hypotension, tachycardia secondary-to-heavy bleeding

Initial Stabilization/Therapy

ABCs:

  • Packed RBCs for significant bleeding unresponsive to crystalloids

Ed Treatment/Procedures

  • Observation usually adequate if bleeding is mild
  • IV crystalloids, packed RBCs for continued bleeding, or hemodynamic instability
  • Gynecology consultation if bleeding is severe and unresponsive to crystalloids, medications:
    • D&C may be necessary for hemodynamic instability
    • Endometrial ablation or hysterectomy for continued heavy bleeding unresponsive to other measures

Medication

  • For acute AUB, hormonal management is first line
  • Conjugated estrogen (Premarin) for heavy bleeding, hemodynamic instability:
    • 2.5 mg PO q6h
    • 25 mg IV, repeat in 3 hr, if needed
    • Medroxyprogesterone acetate 5–10 mg/d PO is added when bleeding subsides
  • Combined oral contraceptive pills:
    • Ethinyl estradiol 35 mcg and norethindrone 1 mg PO QID for 1 wk
  • Progestin-only pills:
    • Norethindrone acetate 5–15 mg PO daily
    • Medroxyprogesterone acetate 5–30 mg PO daily
  • Levonorgestrel-releasing IUD, depot medroxyprogesterone acetate, transdermal, or long-acting estrogens are other options
  • Nonhormonal therapies:
    • Tranexamic acid (TXA): 1,300 mg PO or 10 mg/kg IV q8h × 5 d (max 60 mg/dose):
      • May be used in conjunction with OCPs
      • Use limited by GI effects, allergy, history of thrombosis
    • Ibuprofen 400–800 mg PO q8h (reduces prostaglandin synthesis)
  • Hormonal management is considered first-line medical therapy in AUB in the absence of known or suspected bleeding diathesis
  • Medications may be deferred in mild cases with referral to gynecology

Follow-Up

Disposition

Admission Criteria

  • Symptomatic anemia due to blood loss
  • Persistent bleeding
  • Hemodynamic instability requiring aggressive resuscitation and/or operative intervention

Discharge Criteria

Most patients may be discharged with gynecology referral once bleeding is controlled and patient is hemodynamically stable

Issues For Referral

  • Endometrial biopsy if >45 yr old or risk factors
  • Follow-up with either gynecologist or primary care physician is necessary for patients with AUB
  • Must evaluate for ongoing blood loss or potential malignancy as cause

Pearls And Pitfalls

  • The etiologies of AUB are classified in the PALM-COEIN system
  • Medical management should be the first-line treatment for most patients with AUB
  • Only 2% of endometrial carcinoma occurs before age 40 yr
  • Must rule out pregnancy complications
  • If hemodynamic instability, diagnosis of AUB is unlikely

Additional Readings

  1. ACOG committee opinion no. 557: Management of acute abnormal uterine bleeding in nonpregnant reproductive-aged women. Obstet Gynecol. 2013;121(4):891–896. Reaffirmed 2024.  [PMID:23635706]
  2. Bradley LD, Gueye NA. The medical management of abnormal uterine bleeding in reproductive-aged women. Am J Obstet Gynecol. 2016;214:31–44.  [PMID:26254516]
  3. Brioso XB, Bolt M, Sammel MD, McKenney K. Abnormal uterine bleeding in anticoagulated patients by drug class: outcomes and management. Am J Obstet Gynecol. 2023;229(3):318.e1–318.e14.  [PMID:37201695]
  4. Elmaoğulları S, Aycan Z. Abnormal uterine bleeding in adolescents. J Clin Res Pediatr Endocrinol. 2018;10(3):191–197.  [PMID:29537383]
  5. Munro MG, Critchley HOD, Fraser IS; FIGO Menstrual Disorders Committee. The two FIGO systems for normal and abnormal uterine bleeding symptoms and classification of causes of abnormal uterine bleeding in the reproductive years: 2018 revisions [published correction appears in Int J Gynaecol Obstet. 2019;144(2):237.]. Int J Gynaecol Obstet. 2018;143(3):393–408.  [PMID:30198563]

Authors

Stephanie A. Crapo