LEP and endometriosis: A positive and significant correlation was observed between leptin and OB-RL transcripts in the ectopic endometrium of patients with endometriosis (R = 0.57,  P < 0.01) and in the eutopic endometrium of both endometriosis and control participants (endometriosis: R = 0.52,  P < 0.01; nonendometriosis controls: R = 0.57,  P < 0.02).