On the other hand, it seems that the dysregulation of local prolactin receptor signalling or higher levels of local prolactin could also impair reproduction, acting as a proinflammatory cytokine and angiogenic factor [19], thus contributing to the development of endometriosis or as an immunomodulating factor that participates in activating a local inflammatory environment favourable for the persistence of endometriosis. This evidence concerns the gene PRLR and endometriosis.