Is it okay to undergo an endometrial biopsy while menstruating (on period)?

Endometrial Biopsy During Menstruation

Endometrial biopsy should generally not be performed during menstruation as it can interfere with accurate diagnosis and tissue sampling. 1, 2

Rationale for Avoiding Biopsy During Menstruation

• Menstrual bleeding can:
  • Contaminate tissue samples with blood and menstrual debris
  • Make it difficult to obtain adequate tissue for evaluation
  • Potentially lead to false-negative results or insufficient samples
  • Complicate pathological interpretation of the endometrial tissue

Optimal Timing for Endometrial Biopsy

For diagnostic accuracy, endometrial biopsy should be performed:

• In premenopausal women:

  • Ideally during the early secretory phase (days 7-10 after ovulation) 3
  • After menstrual bleeding has stopped completely
  • Before day 12 of the cycle if evaluating for luteal phase defects 3

• In postmenopausal women:

  • Timing is less critical since there is no cyclical bleeding
  • Should be performed promptly when abnormal bleeding occurs 1, 4

Procedural Considerations

• If an endometrial biopsy must be performed urgently and the patient is menstruating:

  • Consider postponing for a few days until bleeding subsides
  • If postponement is not possible, be aware that:
    • Sample quality may be compromised
    • False-negative results are more likely
    • Additional follow-up testing may be necessary 4

• Office endometrial biopsies have a false-negative rate of approximately 10% 1, 4

  • A negative endometrial biopsy in a symptomatic patient should be followed by a fractional D&C under anesthesia 1

Diagnostic Alternatives

If immediate evaluation is necessary during menstruation:

• Consider transvaginal ultrasound to assess endometrial thickness and identify gross abnormalities 5
• Hysteroscopy may provide better visualization and targeted biopsies compared to blind sampling techniques 2
  • Hysteroscopy has higher diagnostic accuracy and cost-effectiveness for suspected endometrial malignancy 2

Post-Procedure Considerations

• Normal post-procedure spotting may be difficult to distinguish from menstrual bleeding
• NSAIDs are recommended for post-procedure cramping 5, 6
• Pelvic rest is advised until bleeding resolves 5

Special Considerations

• Pregnancy is the only absolute contraindication to endometrial biopsy 6
• For patients with persistent or recurrent symptoms, further evaluation is warranted even with normal biopsy results 6
• Hysteroscopy with targeted biopsy should be considered if blind sampling is insufficient or inconclusive 2

In summary, while not absolutely contraindicated, performing an endometrial biopsy during menstruation is not ideal and should be avoided when possible to ensure optimal diagnostic accuracy and tissue sampling.