What are the steps for performing an endometrial biopsy?

Endometrial Biopsy: Step-by-Step Procedure

Endometrial biopsy is performed by inserting a narrow suction catheter through the cervix into the uterine cavity, creating negative pressure by withdrawing the piston, and sampling tissue by rotating and moving the catheter in and out of the cavity. 1, 2

Pre-Procedure Preparation

Patient Positioning and Pain Management

• Administer oral NSAIDs (e.g., ibuprofen 600-800 mg) 30-60 minutes before the procedure to reduce cramping 1, 3
• Apply topical lidocaine gel to the cervix before starting to decrease procedural pain 1, 3
• Position the patient in dorsal lithotomy position 2

Equipment Setup

• Use a narrow polyethylene endometrial suction catheter (Pipelle or Vabra device preferred, with sensitivity of 99.6% and 97.1% respectively for detecting endometrial carcinoma) 4
• Have a speculum, tenaculum (only if needed), and antiseptic solution available 1, 2

Procedural Steps

Cervical Access

• Insert a speculum to visualize the cervix 2
• Apply a tenaculum ONLY if absolutely required by cervical mobility or severe uterocervical angulation—routine use increases pain and procedure time without benefit 1
• Cleanse the cervix with antiseptic solution 2

Catheter Insertion and Sampling

• Insert the endometrial biopsy catheter through the cervical os into the uterine cavity 1, 2
• Advance the catheter to the fundus (you may feel resistance at the fundal wall) 2
• Withdraw the catheter piston fully to create suction and negative pressure 1, 2
• Simultaneously rotate (twirl) the catheter while moving it in and out of the uterine cavity—this rolling motion enhances tissue uptake 1, 2
• Continue sampling from multiple areas of the endometrial cavity 2
• Remove the catheter and expel the tissue sample into formalin for pathologic examination 2

Post-Procedure Management

Immediate Aftercare

• Expect cramping as the most common adverse effect—reassure patients this is normal 1, 2
• Provide written aftercare instructions before the procedure 3
• Discuss in advance how the patient prefers to receive results 3

Critical Pitfalls to Avoid

When to Escalate Care

• Never accept a negative or inadequate office endometrial biopsy as definitive in symptomatic patients, especially postmenopausal women—the false-negative rate is approximately 10% 4, 5, 1
• Refer for hysteroscopy with directed biopsy under anesthesia if: the procedure fails, insufficient sample is obtained, or symptoms persist despite normal biopsy results 4, 5, 1
• Postmenopausal women with persistent bleeding require further evaluation even with normal biopsy because blind sampling may miss focal lesions like polyps 1, 3

Contraindications

• Pregnancy is the only absolute contraindication 1
• Avoid during acute pelvic inflammatory disease or acute cervical/vaginal infections 2

Technical Considerations

• Inadequate samples occur more commonly in postmenopausal women due to endometrial atrophy 6
• The procedure can be performed without assistance and is relatively easy to learn 2
• Serious complications are rare, though prophylactic antibiotics may be considered in select high-risk patients 2