A 65-year-old postmenopausal female presents to the office with a 6-month history of irregular vaginal bleeding. Pap smear is normal, vaginal mucosa is minimally atrophic, and her uterus is of normal size, shape and consistency and nontender. No adnexal masses are palpated. There are mild tissue texture abnormalities at T10-L2, although no restriction in motion is noted. The most appropriate next step is to