Fig. 1From: Progression of bowel endometriosis during treatment with the oral contraceptive pillLeft, sagittal reconstruction of MDCT-e performed in 2005; a small endometriotic nodule (indicated by the red arrow) determines a retraction of the serosal surface of the sigmoid colon. Right, sagittal reconstruction of MR-e performed in 2009; the blue arrow indicates a large endometriotic nodule infiltrating the muscular layer of the sigmoid colonBack to article page