What Is an Endometrial Biopsy?

An endometrial biopsy—also known as an endometrial tissue sampling—is a procedure where a special tool enters your cervix and uterus to take a tissue sample from the endometrium. The endometrium is the lining of the uterus.

A gynecologist (a medical doctor who specializes in conditions of the female reproductive system) can use an endometrial biopsy to determine the cause of abnormal vaginal bleeding, look for signs of uterine cancer, and check for fertility problems.

Purpose

The purpose of an endometrial biopsy is to determine the cause of symptoms that affect the endometrium. An endometrial biopsy is considered a safe and efficient way to evaluate the endometrium and diagnose uterine conditions. 

Your gynecologist may recommend an endometrial biopsy if you have developed: 

• Abnormal vaginal bleeding
• Vaginal bleeding after menopause
• Fertility concerns
• Abnormal thickening of the uterine lining (usually detected with an ultrasound)

Abnormal vaginal bleeding is a common symptom of endometrial cancer, a type of cancer that starts in the uterine lining. Bleeding could also be a sign of atypical hyperplasia, a precancerous condition that causes the endometrium to thicken. 

In people who have gone through menopause, an endometrial biopsy is considered 90% sensitive to endometrial cancer and 82% sensitive to atypical hyperplasia. Your gynecologist may recommend an endometrial biopsy if you experience abnormal uterine bleeding and have any risk factors for atypical hyperplasia including:

• Age over 45
• Diabetes mellitus
• High blood pressure
• Infertility
• Early menarche (start of menstrual period)
• Late menopause
• Obesity
• Family history of atypical hyperplasia 
• Polycystic ovary syndrome (PCOS)
• History of Tamoxifen use (medication used to treat breast cancer)
• Thyroid disease
• History of estrogen therapy
  

How Does It Work?

An endometrial biopsy is a procedure that examines the endometrium to determine the cause of abnormal vaginal bleeding or provide additional information during a fertility evaluation. During an endometrial biopsy, the gynecologist inserts a thin, flexible tube through the cervix and into the uterus.

During the test, it is possible to feel cramping and some discomfort. Once your provider obtains a tissue sample of your endometrium, a pathologist (or a doctor who specializes in studying body tissues, fluids, and organs) will examine the sample under a microscope in the lab. 

Before the Test

Your gynecologist will likely perform an endometrial biopsy in their outpatient clinic. When you arrive for your appointment, check in with the front desk. You will be given health screening questionnaires and a waiver to sign. If your provider sent any forms to you in the mail or through email, bring those with you to your biopsy.

Before your biopsy, you will change into a hospital gown. If there is any chance that you could be pregnant, your provider will administer a pregnancy test. An endometrial biopsy is not safe for pregnant people and can cause serious complications. 

Talk with your provider ahead of time about the pain management plan before your biopsy. Some healthcare providers recommend taking a non-steroidal anti-inflammatory drug (NSAID) like Advil (ibuprofen) about 30 to 60 minutes before the biopsy to help with the discomfort. 

During the Test

When you are ready for the biopsy, you will lie down on the exam table and place your feet in stirrups at the end of the table. This will feel very similar to how you prepare for a pelvic exam.

Your provider will gently insert a speculum (a metal instrument used to hold the vagina open) into your vagina and slowly open it. They will then use a special liquid to clean the cervix, which is the opening to the uterus. They may also administer a local numbing medication, such as a lidocaine injection, spray, or gel a few minutes before performing the biopsy.

Once your provider has opened the cervix, they will insert a thin, flexible tube through the vagina and the cervix, into the uterus. This tube is a catheter with a suction device attached to it. The catheter takes about one minute to obtain a sample of the endometrium using suction. 

After obtaining the tissue sample, your provider will remove the catheter. You may notice that the tube is filled with dark red tissue. This is the sample that will be sent to the lab for examination. Your provider will also remove the speculum and any other tools that were used.

It is normal to feel some discomfort during the biopsy. The tools used to hold the vagina open and obtain the tissue sample may feel cold. You may also experience cramping that mimics the feeling of menstrual cramps. The discomfort is usually mild but can be severe for some people. If you are in pain during or after the procedure, tell your provider and they can help administer treatment to reduce symptoms.

After the Test

After an endometrial biopsy, your gynecologist will stop any bleeding by applying pressure with a cotton swab. If needed, they may apply a silver nitrate solution to stop the bleeding. 

Plan to remain lying down for a few minutes after the test. Sitting up too quickly could lead to you feeling lightheaded or fainting. Once you feel ready to sit up, you will be able to get dressed and drive yourself home.

After an endometrial biopsy, it is common to experience cramping and spotting for a few days. Call your healthcare provider if you experience any of the following symptoms because they could be a sign of a serious complication:

• Fever
• Persistent cramping that does not improve after a day or two
• Vaginal bleeding that is heavier than a menstrual period 

Risks and Precautions

Every medical test comes with certain risks, and an endometrial biopsy is not safe for everyone. This type of biopsy is not safe for pregnant people. Tell your healthcare provider if there is any chance you could be pregnant. 

An endometrial biopsy might also not be safe for people with the following conditions:

• Coagulopathy: Problem with blood clotting
• Vaginal or cervical infection: If you have an infection in your vagina or cervix, an endometrial biopsy could cause the infection to spread to your uterus

An endometrial biopsy is usually safe but may cause the following complications:

• Heavy bleeding
• Pelvic cramping or pain
• Infection
• Perforation (a hole or tear in the uterine wall)

How to Prepare for an Endometrial Biopsy

It is normal to feel nervous or unsure before an endometrial biopsy. Fortunately, there are steps that you can take to feel more prepared. Consider the following details when preparing for an endometrial biopsy:

• Location: In most cases, gynecologists perform endometrial biopsies in their outpatient office or clinic.
• Attire: When you arrive for your biopsy appointment, you will be given a hospital gown to change into. Plan to bring loose, comfortable clothing to put on after the procedure. You may also want to bring a sanitary pad because you could experience bleeding. 
• Food and drink: Unless you are receiving anesthesia for your procedure, plan to eat and drink normally before the biopsy appointment.  
• Medications: Talk with your healthcare provider about your current medications before your biopsy. They may recommend stopping medications that thin the blood, such as Coumadin (warfarin), because blood thinners could increase the risk of bleeding. 
• Pregnancy: If there is a chance that you could be pregnant, consider taking a pregnancy test before your endometrial biopsy or tell your healthcare team if you think you may be pregnant so they can perform a test in the clinic. This biopsy is not safe for pregnant people. 
• Vaginal health: Do not place any medications or creams on or in your vagina for two days before your biopsy. Avoid sex and douching as well.
• Items to bring: Plan to bring your insurance card and government-issued identification card to your biopsy appointment. 
• Emotional support: If you would like to bring a friend or family member to your appointment, ask your healthcare team where they can wait during the procedure. If you received anesthesia, you will need someone to drive you home. 
• Cost and insurance: An endometrial biopsy is a safe, effective, cost-efficient test and is usually covered by insurance. Consider calling your insurance company before your appointment to ask for a copay estimate. The current reasonable fair price for an endometrial biopsy is $750.  

Results 

Once the pathologist examines your tissue sample, they will write a report and send it to your gynecologist. Your healthcare provider will then contact you via phone, email, electronic medical record, or health app to tell you more about your results.

Interpreting Your Results

When your healthcare provider contacts you, they will explain your results and answer any questions you have. Your test results will likely fall into one of these categories:

• Normal result: A normal result means that the pathologist did not see any signs of cancer or disease. No further testing is needed.  
• Abnormal result: An abnormal result means that the pathologist detected a health problem or disease. This could include uterine cancer, uterine fibroids, uterine polyps, or an infection. If you receive an abnormal test result, your gynecologist will discuss the next steps and treatment options with you. 
• Inconclusive result: An inconclusive result means that your pathologist did not detect any signs of disease but cannot rule them out either. It is not uncommon for the pathologist to determine that the sample was insufficient. Up to 31% of people who had an endometrial biopsy need to repeat the test because their provider did not obtain a large enough sample to test.

A Quick Review 

An endometrial biopsy is a medical procedure that a gynecologist will perform to determine the cause of abnormal vaginal bleeding and fertility challenges. This test can also check for signs of uterine or endometrial cancers.

During an endometrial biopsy, your provider will insert a thin, flexible catheter through the vagina and cervix and into the uterus. The catheter uses suction to obtain a tissue sample from the endometrium, the lining of the uterus. The tissue sample will be sent to a pathologist for proper testing.

Keep in mind: it's normal to experience cramping or discomfort during an endometrial biopsy. If you experience pain during the procedure, tell your provider. In most cases, your provider will numb the cervix with a local anesthetic before performing the biopsy or administer pain medication after to reduce discomfort.