SERPINE1 and adenomyosis: To investigate the expression and localization of PAI-1 in endometria with and without adenomyosis and to determine the relationship between PAI-1 immunoreactivity and the severity of dysmenorrhea and the extent of lesional fibrosis in adenomyosis, immunohistochemistry experiment, Masson’s trichrome staining, and correlation analysis between adenomyotic PAI-1 expression and the severity of dysmenorrhea and the extent of lesional fibrosis were performed.