Knowing the multiple mechanisms through which the NK cell may be involved in the development of adenomyosis /endometriosis (e.g., cell recognition process, integrin production, and angiogenic abilities), we can speculate that the hysteroscopic modifications identified in the KIR AA patients may be regarded as stages that precede the development of these pathological conditions [16,20,21]. The gene discussed is KIR3DL1; the disease is endometriosis.