A lower expression of Drosha was observed in the eutopic endometrium of women with adenomyosis than in the eutopic endometrium of women without the disease (69.9±3.4% vs 85.2±2.9%, respectively) (P=0.016; 95%CI of the difference: 3.4 to 27.4%). The gene discussed is DROSHA; the disease is adenomyosis.