The outside measurement of you hips has nothing to do with how big of a pelvic intlet you have (the space for the baby to come through. Some "large" hipped women have a small space and some "small" hipped women have quite a large space.
You just can't know until the baby comes. I've known many small women have very big headed babies. It would be exremely rare for the baby to really not fit. Although that excuse is given to mothers too often--as are many other excuses to get them to do interventions like inductions or C/S. Don't believe them. As long as you and the baby are testing fine--everything is okay.
I am a large hipped woman who "they" claim has too small of an inlet (CPD) to birth my large babies. I'm still attempting it for the third time (HBA2C)--because how do "they" know? I just don't buy it. I found a more patient care giver this time and it WILL work! (The first two times, supposedly conservative MDs, talked me into interventions that I regretted and ended up with C/S.)
Mom to 5 amazing kids! (DS10, DS8, DD5, DD3 and DS1)