How far along is she? If she's in the 3rd trimester and still has a complete previa, I think her odds of it resolving are unfortunately very low and a c/s will be required. Mine was found at 21.5 weeks. I'll be having an u/s at 30 weeks to see if it's moved, and again at 34 if it hasn't completely resolved by the first u/s. It's possible for the placenta to move during the 3rd trimester, but very unlikely.