At the ACOG meeting last May, Dr. Robert Wachter talked about a case in a teaching hospital in which two women with similar names -- Jane Morrison and Joan Morris are the pseudonyms assigned to them -- were confused with one another, resulting in one of them receiving an invasive procedure intended for the other one. This case did not involve a birth story, but every medical specialty can take lessons away from it.

This case, which Dr. Wachter and colleagues published as "The Wrong Patient," in June, 2002, in the Annals of Internal Medicine, demonstrates how easily a series of oversights can cascade into a shocking medical error. (It could have been worse. The procedure was a cardiac electrophysiology study, not, say, a leg amputation.)

In fact, the team that analyzed the mishap identified 17 junctures at which the process could have been stopped but instead moved forward. No single mistake would have been enough to keep this juggernaut moving. Human error fed into institutional weaknesses, including "frighteningly poor communication," a lack of standardized protocols and a culture that had become sufficiently dysfunctional that more than one person thought, incredibly, Gee, this doesn't seem right, but I'm going to do it anyway.

"Human performance can beimproved but not perfected," the team concluded. Protocols must be in place to head off the inevitable errors before they converge into tragedy.