Embryologic theory of histogenesis of endometriosis in peritoneal pockets.

A novel presentation of endometriosis is described in which the lesion is identified within the brim or floor of peritoneal pockets located within a crescentic band in the posterior pelvis. The predictability of these peritoneal pockets and their strong association with other anomalies of the Mullerian and urinary tracts raises the possibility of a congenital origin.