Background. Polycystic ovary syndrome (PCOS) has been accompanied by insulin resistance. The aim of this study was to compare the insulin action between thin and obese women with PCOS and to analyse its relationship to serum concentration of selected hormones. Methods and Results. Total number of 32 women with PCOS between them there were 22 thin and 10 obese subjects was examined in this study. Control group consisted of 21 nonobese healthy women. The insulin action was determined by euglycemic hyperinsulinemic clamp. Normal insulin action found in the group of thin women with PCOS was comparable with that in healthy controls whereas insulin resistance was observed in obese ones. An inverse relationship was found between insulin action and body mass index (r=0.62, p<0.01). By using HOMA index this relationship to BMI was on the borderline significance. No correlation was observed between insulin action and serum hormone concentrations (testosterone, androstendione, LH, FSH) but sex hormone binding globulin (SHBG) positively correlated with parameters of insulin action (r=0.50–0.54). Conclusions. The insulin action may be normal in thin women with PCOS whereas obesity and other not yet disclosed factors influence development of insulin resistance in women with polycystic ovary syndrome.

        Key words: polycystic ovary syndrome, insulin action, euglycemic clamp.