Half of the samples were obtained during the proliferative phase of the menstrual cycle in the present study, and the expression of the four genes analyzed (PAQR7, PAQR8, PAQR5, and PAQR6) was decreased in the eutopic endometrium of patients with endometriosis compared to the endometrium of control women. This evidence concerns the gene PAQR5 and endometriosis.