Endometrial Biopsy (Procedure)

The uterus (womb) is lined by a special type of tissue known as the endometrium. Endometrial biopsy, or endometrial sampling, is a technique of removing a piece of tissue from the inner lining of the uterus. The sample of tissue is analyzed under a microscope in the laboratory by a pathologist, a doctor with special training in diagnosis of diseases based upon tissue examination.

Usually, endometrial biopsy procedures painful, and women who are having the procedure should be notified. There are drugs to stop the pain caused by the biopsy. Endometriosis can have an impact psychologicaly on women with the condition due to severe pain. Moreover, the severe pain caused by endometriosis is compounded negatively by the inability to conceive.  

An endometrial biopsy is most often performed to help determine the cause of abnormal uterine bleeding. It can also be done to help evaluate the cause of infertility, test for uterine infections, and even monitor the response to certain medications.

Endometrial biopsy has many advantages over the more complicated procedure known as dilation and curettage (D&C), which is a more extensive removal of the uterine lining that requires dilation (stretching) of the cervical opening with special instruments. Unlike D&C, endometrial biopsy may be performed in the doctor's office and typically does not require anesthesia or hospitalization.

Endometrial biopsy cannot be performed during pregnancy, and sometimes may not be recommended when certain other conditions are present, including cancer of the cervix or abnormal narrowing (stenosis) of the cervical opening.

Endometrial biopsy is most often done in the physician's office, but it can be performed on women in the hospital. The patient lies on the examining table in a position similar to that used for obtaining Pap smears. The doctor uses a speculum to open the vaginal canal and visualize the cervix, the opening to the uterus. During endometrial biopsy the doctor inserts a thin plastic or metal tubular device through the cervix into the uterus to remove a tiny piece of the inner lining tissue.

Picture of the female reproductive system

Usually no anesthesia is required, but taking a nonsteroidal anti-inflammatory medication (NSAID) 30 to 60 minutes prior to the procedure can help reduce cramping and pain. In some cases, a small amount of lidocaine anesthetic is inserted into the uterine cavity to minimize discomfort.

There are very few risks with endometrial biopsy. The leading risk is pain or cramping, but this typically subsides rapidly following the procedure. Other less common risks are:

1. Feeling faint or light-headed
2. Infection
3. Bleeding
4. Rarely, perforation of the uterus