Here's another story for you:

I recently had a client who had 10 cm fibroid in the lower segment which filled the pelvis in first trimester and resulted in a fundus at the level of the umbi at 12 weeks gestation. We (I did shared care with an Ob) thought she would have to have a c/s but because the lower segment grows during a pregnancy, the fibroid (like a low lying placenta placenta) moved up out of the pelvis by fullterm and she had a beautiful vaginal birth.

So wait and see ...