Endometrial biopsy, or endometrial sampling, is a used to evaluated the inner lining of the uterus. The sample of tissue is analyzed under a microscope in the laboratory by a pathologist, a doctor special training in diagnosis of diseases based upon tissue examination.

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. A small amount of lidocaine anesthetic is inserted into the uterine cavity to minimize discomfort.