ABSTRACT
The etiology and pathogenesis have not been fully elucidated. Many theories have been proposed, but no single theory sufficiently accounts for all aspects of this enigmatic disease, which makes it likely that several mechanisms are involved.2 An alternative explanation is that endometriosis is a heterogeneous rather than a single disease: in other words, peritoneal, deeply infiltrating, ovarian, and extrapelvic endometriosis are manifestations of different disease processes, each with their own etiology.3
