What is the initial workup for a patient presenting with postmenopausal bleeding?

Initial Workup for Postmenopausal Bleeding

Transvaginal ultrasound (TVUS) should be the first-line imaging test for all women presenting with postmenopausal bleeding to measure endometrial thickness and identify structural abnormalities of the uterus, endometrium, and ovaries. 1

Diagnostic Algorithm

Step 1: Initial Assessment

• Postmenopausal bleeding occurs in approximately 10% of women over age 55 and requires urgent referral due to 10% risk of endometrial cancer 2
• Obtain detailed history including:
  • Duration and amount of bleeding
  • Associated symptoms (pain, discharge)
  • Risk factors for endometrial cancer (obesity, diabetes, hypertension, tamoxifen use) 3
  • Medication history (HRT, tamoxifen, anticoagulants) 2

Step 2: First-Line Investigation - Transvaginal Ultrasound

• TVUS is the preferred initial diagnostic test as it is less invasive, generally painless, and has no complications 3
• TVUS helps differentiate between structural causes (polyps, adenomyosis, leiomyoma, malignancy, hyperplasia) and non-structural causes of bleeding 3
• An endometrial thickness of ≤4 mm on TVUS has a negative predictive value for cancer of nearly 100% 1

Step 3: Endometrial Sampling

• If endometrial thickness is ≥5 mm on TVUS, endometrial tissue sampling is indicated 1
• Office endometrial biopsy is the standard method for obtaining tissue for histological assessment 1
• Endometrial biopsy using devices such as Pipelle has extremely high sensitivity (99.6%) for detecting endometrial carcinoma 3

Step 4: Follow-up Evaluation

• If office endometrial biopsy is negative but bleeding persists, or if the biopsy is non-diagnostic, a fractional dilation and curettage (D&C) under anesthesia should be performed 1
• Hysteroscopy should be considered for evaluating the endometrium for lesions such as polyps if the patient has persistent or recurrent undiagnosed bleeding 1

Common Causes of Postmenopausal Bleeding

• Atrophic endometritis and vaginitis (21.2%) 4
• Endometrial hyperplasia (10.4%) 5
• Endometrial carcinoma (10.4%) 5
• Endometrial polyps (9.2%) 5
• Other causes: cervical carcinoma, hormone-producing ovarian tumors, haematuria and rectal bleeding 2

Important Clinical Considerations

Risk Factors Requiring Special Attention

• Age >60 years significantly increases risk of endometrial cancer 5
• Endometrial volume ≥3 mL on TVUS is associated with higher prevalence of endometrial hyperplasia and cancer 5
• Women with Lynch syndrome have 30-60% lifetime risk of endometrial cancer and require specialized surveillance 3

Clinical Pitfalls to Avoid

• Relying solely on Pap smear for evaluation of postmenopausal bleeding may miss endometrial pathology, as Pap smear is designed to screen for cervical cancer, not endometrial cancer 1
• Using endometrial thickness cutoffs higher than 4 mm may miss cases of endometrial cancer 1
• Failing to pursue further evaluation when initial tests are negative but bleeding persists 1
• Overlooking rare causes of postmenopausal bleeding such as hematologic malignancies 6 or trauma-related causes 7

Special Imaging Considerations

• If TVUS cannot adequately evaluate the endometrium due to patient factors or pathology, MRI can be considered 1
• Saline infusion sonography can be used to distinguish between focal and diffuse pathology 1