I used to work at a urology office and we saw a lot of women with a condition called a prolapsed uterus. From my understanding, this can happen over time as a women gets older and has had multiple pregnancies and natural births.
One way a women experiencing a slight prolapsed uterus, or a woman who wants to keep her pelvic muscles strong is to do an exercise called kegals.
Her doctor, or even a physical therapist who specializes in women's health, can teach her how to do this.
It's a great first step that can hopefully keep her from having surgery or at least hold off the surgery for a while. My mom does them and has not needed the surgery. I am starting to do them as well, as a proactive step.