Your practitioner may suggest an endometrial biopsy if you are having irregular bleeding. This is done for diagnosis and may let us know if you have a polyp, precancerous uterine cells or even cancer. Your practitioner will introduce an appropriately sized speculum and may numb your uterus with lidocaine. If your cervix is not open, we may need to stabilize your cervix with an instrument called a tenaculum. A long, thin tube will then be introduced through your cervix and into your uterus. You may feel strong menstrual cramps, which usually resolve within a few minutes. You may resume normal activities after an endometrial biopsy.