My sister had 4 C sections. She had her 1st by C/S (a boy) then had a VBAC with my niece, the only girl. It was a horrible, horrible delivery that was worse than any of her C/S ever were. Her following 3 boys were all C/S. After baby#4, my oldest nephew decided that boys are born by C/S and girls are born "the other way."
Speaking from 8 years of OB nursing experience, if the uterine incision is a low, transverse incision, the risks are not as high as they are with a high and/or vertical incision.