I Have About Stage 3 Uterine Prolapse And Have Gone

I have about stage 3 uterine prolapse and have gone through menopause, am 68 yrs old and still sexually active. Why would I elect to do a surgery reconstructive procedure rather than have a vaginal hystectomy?
I am tentatively scheduled for reconstruction next month but have been having a pain between my hipbone and the bottom of my rib cage on the left side at the end of the day, but not every day. Is this a normal progression of the prolapse ant the ligaments & muscles holding up the uterus are stretching. Am I on my feet too long during the day perhaps? I am fine the next day.