Hospitals that do not have 24 hour on-site anesthesia staff sometimes choose to ban VBAC, despite the fact that immediately available surgical teams present throughout a VBAC labor have not been shown to improve outcomes in the event of uterine rupture. In fact, there are other emergencies that can occur during any labor that are just as dangerous, and more common than uterine rupture. "Current risk management policies across the United States restricting [VBAC] after previous cesarean section appear to be based on malpractice concerns rather than on available statistical and scientific evidence."