Third, an endometrial biopsy will be performed by one of the doctors running the study. This will require you to have a full pelvic exam (much like when you have a pap smear), which will include looking at the cervix (mouth of the womb) and putting a small pipelle (straw) into the womb to collect a tissue sample. This procedure is routinely done in the office. You will not be required to take medications prior to the procedure and you will not receive a prescription for pain medication once the procedure is complete.