Pipelle Versus Karman Endometrial Biopsy Under Standardized Paracervical Block (PB-EMB)

February 9, 2026 updated by: Havva Betül Bacak, Gaziosmanpasa Research and Education Hospital

Comparison of Pipelle and Karman Endometrial Biopsy Methods Under Standardized Paracervical Block: A Prospective Randomized Study

Endometrial biopsy is a commonly used outpatient procedure to evaluate abnormal uterine bleeding and postmenopausal bleeding. Different sampling methods are available, but their diagnostic adequacy and patient experience may vary.

This prospective randomized study compares two commonly used endometrial biopsy methods, Pipelle and Karman cannula, under standardized paracervical block anesthesia. All participants receive the same local anesthetic technique to minimize pain-related differences between methods.

The primary objective is to compare the rate of clinically adequate endometrial samples obtained with each method. Secondary outcomes include patient-reported pain, patient satisfaction, procedure duration, need for additional diagnostic procedures, and hospital-related costs.

Study findings are expected to support clinical decision-making regarding the most effective and practical endometrial biopsy method when adequate pain control is provided.

Study Overview

Status

Completed

Conditions

Intervention / Treatment

Detailed Description

Endometrial biopsy is an essential diagnostic procedure in the evaluation of abnormal uterine bleeding and postmenopausal bleeding. Office-based endometrial sampling techniques are widely used because these techniques are minimally invasive and cost-effective; however, diagnostic adequacy, patient tolerance, and resource utilization may differ between methods.

Pain during the procedure is a major factor affecting patient experience and may confound comparisons between sampling techniques. To address this limitation, participants receive a standardized paracervical block using the same anesthetic agent, dose, and technique, allowing the comparison to focus on the intrinsic performance of the biopsy methods rather than differences in analgesia.

This is a prospective, randomized, parallel-group study. Eligible participants undergoing endometrial biopsy are randomly assigned in a 1:1 ratio to either Pipelle endometrial biopsy or Karman cannula endometrial sampling. Randomization is stratified by menopausal status. Procedures are performed in an outpatient setting according to routine clinical practice.

Histopathological evaluation of endometrial samples is performed by pathologists blinded to the sampling method. Sample adequacy is assessed based on predefined criteria, with a focus on whether the specimen provides sufficient information for clinical decision-making.

In addition to diagnostic adequacy, patient-reported outcomes, including pain and satisfaction with the procedure, are assessed. Procedure duration, need for additional diagnostic interventions due to inadequate sampling, and hospital-related costs associated with each method are also evaluated.

Standardized analgesia and inclusion of clinical, patient-centered, and economic outcomes are intended to provide practical evidence to guide the selection of endometrial biopsy methods in routine gynecologic practice.

Study Type

Interventional

Enrollment (Actual)

480

Phase

  • Not Applicable

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Locations

  • Turkey (Türkiye)
      • Istanbul, Turkey (Türkiye)
        • University of Health Sciences, Gaziosmanpaşa Training and Research Hospital

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Ages Eligible for Study

  • Adult
  • Older Adult

Accepts Healthy Volunteers

No

Description

Inclusion Criteria:

  • Female participants aged 18 years or older
  • Abnormal uterine bleeding or postmenopausal bleeding requiring endometrial sampling
  • Ability to provide written informed consent
  • Eligible for office-based endometrial biopsy

Exclusion Criteria:

  • Pregnancy
  • Active pelvic infection
  • Known cervical or endometrial cancer
  • Severe cervical stenosis preventing endometrial sampling
  • Known bleeding disorders or use of anticoagulant therapy that contraindicates biopsy
  • Inability or unwillingness to provide informed consent

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

  • Primary Purpose: Diagnostic
  • Allocation: Randomized
  • Interventional Model: Parallel Assignment
  • Masking: Single

Arms and Interventions

Participant Group / Arm
Intervention / Treatment
Experimental: Pipelle Endometrial Biopsy
Participants assigned to this arm undergo office-based endometrial biopsy using a Pipelle device. All procedures are performed under standardized paracervical block anesthesia with the same anesthetic agent, dose, and technique as the other study arm.
Device: Pipelle Endometrial Biopsy
Endometrial sampling performed using a Pipelle device in an outpatient setting. The procedure is conducted under standardized paracervical block anesthesia using the same anesthetic agent, dose, and technique for all participants.
Other Names:
  • Pipelle de Cornier
Experimental: Karman Endometrial Biopsy
Participants assigned to this arm undergo office-based endometrial sampling using a Karman cannula. All procedures are performed under standardized paracervical block anesthesia with the same anesthetic agent, dose, and technique as the other study arm.
Device: Karman Cannula Endometrial Biopsy
Endometrial sampling performed using a Karman cannula in an outpatient setting. The procedure is conducted under standardized paracervical block anesthesia using the same anesthetic agent, dose, and technique for all participants.
Other Names:
  • Karman Cannula
  • Manual Vacuum Aspiration Cannula

What is the study measuring?

Primary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Clinically Adequate Endometrial Sample Rate
Time Frame: At the index procedure (same day)
Proportion of endometrial biopsy samples considered clinically adequate for diagnosis based on blinded histopathological assessment.
At the index procedure (same day)

Secondary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Procedure-Related Pain Score
Time Frame: Periprocedural
Eligible participants undergo outpatient endometrial sampling under a standardized analgesia protocol: 3 mL of 2% prilocaine is injected for a paracervical block at the 1 and 11 o'clock positions before tenaculum application, followed by a 2-minute waiting period; a tenaculum is then applied and endometrial sampling is performed using either a Pipelle device or a 5-mm Karman cannula according to random assignment. Sampling is recorded as the number of predefined sampling cycles (maximum 3), and cervical stenosis, need for dilation, procedure duration, additional analgesia (e.g., NSAIDs), and complications are documented. Specimens are placed immediately in formalin in identical containers labeled with study ID only, sent daily in mixed order, and evaluated by pathologists blinded to sampling method for adequacy and diagnosis (including reason for inadequacy). Pain is assessed using the Visual Analog Scale for Pain (0-10; higher scores indicate worse pain) during the procedure and at 3
Periprocedural
Patient Satisfaction With the Procedure
Time Frame: Same day after the procedure
Patient-reported satisfaction with the endometrial biopsy procedure assessed using a Likert-type questionnaire, including willingness to undergo the same procedure again if needed.
Same day after the procedure
Procedure Duration
Time Frame: During the procedure
Time required to complete the endometrial biopsy procedure, measured from speculum insertion to completion of tissue sampling.
During the procedure
Need for Additional Diagnostic Procedures
Time Frame: Within 2 weeks after the procedure
Proportion of participants requiring additional diagnostic procedures due to an inadequate endometrial biopsy sample.
Within 2 weeks after the procedure
Hospital-Related Cost per Participant
Time Frame: Within 2 weeks after the procedure
Total hospital-related cost per participant, including procedural costs and costs related to additional diagnostic interventions when required.
Within 2 weeks after the procedure

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Sponsor

Gaziosmanpasa Research and Education Hospital

Investigators

  • Study Director: Fatma Ketenci Gencer, Assoc. Prof., University of Health Sciences, Gaziosmanpaşa Training and Research Hospital

Publications and helpful links

The person responsible for entering information about the study voluntarily provides these publications. These may be about anything related to the study.

General Publications

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start (Actual)

January 3, 2026

Primary Completion (Actual)

January 31, 2026

Study Completion (Actual)

February 9, 2026

Study Registration Dates

First Submitted

January 3, 2026

First Submitted That Met QC Criteria

January 16, 2026

First Posted (Actual)

January 26, 2026

Study Record Updates

Last Update Posted (Actual)

February 10, 2026

Last Update Submitted That Met QC Criteria

February 9, 2026

Last Verified

January 1, 2026

More Information

Terms related to this study

Keywords

Additional Relevant MeSH Terms

Other Study ID Numbers

  • EK-193-2025-EMB

Plan for Individual participant data (IPD)

Plan to Share Individual Participant Data (IPD)?

NO

IPD Plan Description

Individual participant data will not be shared due to local ethical regulations and the need to protect participant privacy. The dataset contains sensitive clinical information, and no consent for public data sharing was obtained from participants.

Drug and device information, study documents

Studies a U.S. FDA-regulated drug product

No

Studies a U.S. FDA-regulated device product

No

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

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