The goal of this pilot study is to characterize the presence and stability of the microbial community in the vagina and lower urinary tract in a cohort of 20 postmenopausal women undergoing transvaginal hysterectomy with pelvic reconstruction for pelvic organ prolapse. The investigators intend to collect longitudinal samples in the preoperative, intraoperative, and postoperative time period in order to understand the pervasiveness of the microbes in the vagina and lower urinary tract, and to identify, in a very preliminary way, particular microbes that may be associated with postoperative urinary tract infection.