Vaginal delivery after cesarean section in women with unknown types of uterine scar.

Documentation of a prior cesarean and the type of uterine scar has been used as one criterion for permitting patients a trial of labor. In a highly mobile patient population such as ours, these medical facts are often difficult or impossible to obtain. As a result, we retrospectively examined the performance of patients with unknown types of cesarean scar and found no difference between them and a similar population with documented low cervical scars. Although obtaining an old record is useful, its absence probably should not interdict a trial of labor in a patient who desires to attempt vaginal delivery.