['To measure and compare concentrations of total and free glucocorticoids with oocyte fertilizing capacity in the follicular fluid (FF) of women with minimal-mild endometriosis and tubal damage.', 'Follicular fluid was collected from individual periovulatory follicles during oocyte retrieval for in vitro fertilization (IVF) in natural cycles. Total and free levels of cortisol and cortisone were measured using specific radioimmunoassays after chloroform extraction.', 'Cortisol concentrations in women with minimal-mild endometriosis were significantly lower compared with controls (women with tubal infective damage) (258 versus 328 nmol/L, P < 0.02). There was no correlation between total or free concentrations of cortisol or cortisone and the fertilization capacity of the oocyte.'] Are total cortisol levels reduced in the periovulatory follicle of infertile women with minimal-mild endometriosis?