The use of closed claims data to identify risk exposures, highlight safety issues, and drive improvement changes have been applied in ambulatory care, surgery, emergency medicine, and obstetrics. This study uses a previously described database to compare liability profiles in obstetric anesthesia before and after 1990. Investigators found that while the proportion of maternal death and newborn death or brain damage claims decreased in recent years (though still a leading cause), maternal nerve injury and back pain increased in later claims. Delays in anesthesia care, substandard care, and poor communication between the obstetrician and anesthesiologist are identified as preventable causes of newborn injury.