Approach to Abnormal Uterine Bleeding (AUB) in the Reproductive Age Group

Definition and Normal Parameters

• Frequency: every 24-38 days
• Duration: 4-8 days of flow
• Volume: not interfering with quality of life

The Normal Menstrual Cycle (Context)

FIGO PALM-COEIN Classification (2011)

PALM - Structural Causes

COEIN - Non-structural Causes

Causes Specific to the Reproductive Age Group

1. Complications of pregnancy - threatened/incomplete/missed abortion, ectopic pregnancy, gestational trophoblastic disease (ALWAYS exclude first)
2. Functional/anovulatory - PCOS (most common cause), hypothalamic dysfunction, hyperprolactinemia, thyroid disease
3. Structural lesions - polyps, leiomyomas (especially submucosal), adenomyosis
4. Coagulation disorders - Von Willebrand disease, ITP
5. Endocrine disorders - diabetes mellitus, hypothyroidism/hyperthyroidism, Cushing syndrome, Addison disease
6. Medications - OCP use, anticoagulants, antipsychotics
7. Iatrogenic/Trauma - post-cesarean scar defect (niche), foreign body, coital trauma
8. Malignancy - endometrial hyperplasia/carcinoma (less common in this age group but must be excluded in high-risk patients)

Clinical Evaluation

Step 1: History

• Characterize the bleeding: frequency, duration, volume (number of pads/tampons, presence of clots, flooding)
• Menstrual calendar - prospective charting may be required
• Relationship of bleeding to the cycle (intermenstrual, postcoital, or heavy regular menses)
• Obstetric history - last menstrual period, sexual activity, contraception
• Symptoms of pregnancy - any possibility must be excluded immediately
• Symptoms of anovulation - irregular cycles, no predictable PMS symptoms
• Symptoms of systemic disease - fatigue, weight change, heat/cold intolerance, galactorrhea
• Bleeding tendency - bruising, epistaxis, family history of bleeding disorder
• Medications - especially anticoagulants, hormonal therapy, antipsychotics
• Risk factors for endometrial cancer - obesity, PCOS, nulliparity, diabetes, family history (Lynch syndrome)

Step 2: Physical Examination

• General: signs of anemia (pallor, tachycardia), signs of hypovolemia in acute bleeding
• Signs of PCOS: obesity, acne, hirsutism, acanthosis nigricans
• Thyroid: nodules, enlargement
• Skin: petechiae, ecchymosis (coagulopathy)
• Abdomen: uterine or adnexal mass
• Pelvic exam: vaginal/cervical lesions, discharge, uterine size and tenderness, bimanual - fibroid uterus palpable
• Speculum: source of bleeding (cervical vs. uterine), cervical lesion requiring biopsy

Investigations

Essential (All Cases)

Imaging

• Pelvic ultrasound (TVUS): First-line imaging. Evaluates endometrial thickness, polyps, fibroids (with FIGO subclassification), adenomyosis, ovarian pathology
• Saline infusion sonohysterography (SIS): Better visualization of intracavitary lesions (polyps, submucosal fibroids)
• MRI: For adenomyosis, complex leiomyoma mapping, or pre-operative planning

Endometrial Sampling - When Indicated

• Age ≥45 years with AUB (including intermenstrual bleeding)
• Age <45 years with risk factors:
  • Unopposed estrogen exposure (obesity, PCOS)
  • Persistent AUB or AUB refractory to medical management
  • Elevated familial cancer risk (Lynch syndrome)
  • Prolonged anovulatory bleeding

Management

Step 1: Resuscitate if Hemodynamically Unstable

Step 2: Medical Management (First-Line)

For Acute Heavy Anovulatory Bleeding (Hemodynamically Stable)

• Combined OCP: One pill every 6 hours for 5-7 days (off-label). Bleeding should cease within 24 hours. Warn the patient to expect heavy withdrawal bleed 2-4 days after stopping.
• Conjugated estrogens IV: 25 mg every 4 hours for up to 3 doses until bleeding ceases, then simultaneously start progestin (medroxyprogesterone acetate 5-10 mg/day for 10 days). Follow with cyclic OCP for at least 3 cycles.
• Progestin alone: Medroxyprogesterone acetate 5-10 mg/day, or norethindrone 5 mg/day, for 10 days - for mild-moderate anovulatory bleeding or where estrogen is contraindicated.

For Chronic/Ongoing Heavy Menstrual Bleeding

Step 3: Cause-Specific Treatment

Step 4: Surgical Management (Second-Line or Refractory Cases)

• Endometrial ablation: Effective in up to 70-80% of cases; not appropriate for women desiring future fertility. Note: 29% undergo eventual hysterectomy by 5 years.
• Uterine artery embolization (UAE): For fibroid-related AUB in women wishing to avoid surgery; 31% ultimately undergo hysterectomy.
• Hysterectomy: Definitive treatment; reserved for patients who fail or cannot tolerate medical therapy, have completed family, or have malignancy. Endometrial sampling should always precede hysterectomy.

Special Considerations in the Reproductive Age Group

1. Always exclude pregnancy first - ectopic pregnancy is a life-threatening emergency that mimics AUB.
2. Coagulopathy screening is indicated when: heavy bleeding since menarche, family history of bleeding disorder, signs of systemic bleeding, or on medications associated with AUB. Up to 20% of women with heavy periods have an undiagnosed coagulopathy.
3. Fertility preservation guides choice of treatment - medical management and uterine-preserving procedures are preferred over hysterectomy in women who desire future pregnancy.
4. PCOS is the most common cause of anovulatory AUB in this age group. Unopposed estrogen in PCOS leads to endometrial proliferation and irregular shedding, and increases long-term risk of endometrial hyperplasia/cancer.
5. Endometrial sampling before any surgical treatment is non-negotiable - D&C alone does not adequately treat AUB and is not required before hysterectomy, but a sample must be obtained.

Summary Algorithm

AUB in Reproductive Age
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Exclude PREGNANCY (beta-hCG) ← ALWAYS first
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Hemodynamic assessment
    Unstable → Resuscitate → IV estrogens / urgent D&C
    Stable ↓
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History + Examination + Labs (CBC, TSH, Prolactin, Coags, VWF)
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Pelvic Ultrasound (TVUS)
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   Structural (PALM)?           Nonstructural (COEIN)?
   Polyp → Hysteroscopy         Anovulatory (PCOS, thyroid) → Medical Rx
   Fibroid → Myomectomy/UAE     Coagulopathy → Haematology referral
   Adenomyosis → LNG-IUS/Hyst  Iatrogenic → Modify medication
   Hyperplasia/Ca → Biopsy      Endometrial cause → Tranexamic acid / NSAIDs
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Endometrial biopsy if age ≥45 or risk factors
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Medical treatment FIRST (OCP / Progestins / LNG-IUS / Tranexamic acid)
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Failure → Surgical (Ablation / Myomectomy / UAE / Hysterectomy)