What is the initial workup for postmenopausal (post-menstrual) bleeding?

Initial Workup for Postmenopausal Bleeding

All women with postmenopausal bleeding should be referred urgently for evaluation, as endometrial cancer is present in approximately 10% of these cases. 1

Diagnostic Algorithm

Step 1: Initial Assessment

• Detailed history focusing on:

  • Duration and amount of bleeding
  • Risk factors for endometrial cancer: obesity, diabetes, hypertension, unopposed estrogen exposure, Lynch syndrome 2
  • Medication history: HRT, tamoxifen, anticoagulants 1

• Physical examination:

  • Abdominal examination for masses
  • Pelvic examination to assess:
    • External genitalia
    • Vaginal atrophy
    • Cervical lesions or polyps
    • Bimanual examination for uterine/adnexal masses 1, 3

Step 2: First-Line Imaging

• Transvaginal ultrasound (TVUS) is the recommended first-line test 2
  • Measure endometrial thickness
  • Assess for structural abnormalities of uterus, endometrium, and ovaries
  • Key threshold: Endometrial thickness ≤4 mm has a negative predictive value for endometrial cancer of nearly 100% 2, 3

Step 3: Tissue Sampling

• Endometrial biopsy is indicated when:

  • Endometrial thickness ≥5 mm on TVUS
  • Persistent or recurrent bleeding regardless of endometrial thickness
  • Inadequate visualization of endometrium on TVUS 2

• Office endometrial sampling devices:

  • Pipelle (sensitivity 99.6% for endometrial carcinoma)
  • Vabra (sensitivity 97.1% for endometrial carcinoma) 2

Step 4: Additional Evaluation

• If office endometrial biopsy is inadequate or non-diagnostic:

  • Proceed to fractional dilation and curettage (D&C) under anesthesia 4
  • Office endometrial biopsies have a false-negative rate of approximately 10% 4

• Hysteroscopy should be considered when:

  • Persistent or recurrent undiagnosed bleeding
  • Focal lesions are suspected
  • Provides direct visualization and targeted biopsy 4, 2

• Saline infusion sonohysterography may be helpful when:

  • TVUS suggests focal pathology (polyps)
  • Can guide decision-making for more invasive procedures 2, 3

Special Considerations

Advanced Imaging

• Additional imaging (CT, MRI, PET/CT) should be considered only when:
  • Extrauterine disease is suspected
  • Clinical symptoms, physical findings, or abnormal laboratory findings suggest metastatic disease 4

Laboratory Testing

• Serum CA-125 may be helpful for monitoring clinical response in patients with extrauterine disease, but is not recommended as part of initial evaluation 4

Genetic Considerations

• Consider screening for Lynch syndrome in patients with risk factors or family history
• Universal testing of endometrial tumors for defects in DNA mismatch repair is recommended when cancer is diagnosed 4

Common Pitfalls

1. Failure to refer urgently - All postmenopausal bleeding should be considered suspicious for malignancy until proven otherwise 1

2. Relying solely on negative endometrial biopsy - False-negative rates of approximately 10% necessitate further evaluation in symptomatic patients 4

3. Ignoring bleeding in women on hormone therapy - Postmenopausal bleeding in women on estrogen therapy still requires full evaluation 5

4. Missing non-gynecologic causes - Remember to consider urinary and gastrointestinal sources of bleeding 6

5. Inadequate follow-up - Even with normal initial evaluation, recurrent bleeding warrants repeat assessment 3