OBJECTIVE To investigate the relationship between the ovarian stromal area and clinical hormonal characteristics in women with polycystic ovary syndrome (PCOS). METHODS Twenty-eight women with PCOS (group 1) and 26 healthy women (group 2) participated in this study. For measuring the ovarian stromal area, transvaginal ultrasonography was performed on all women during the early follicular phase of the menstrual cycle. Venous blood was sampled from the women to determine serum follicle stimulating hormone, luteinizing hormone (LH), estradiol, androstenedione, free testosterone (FT), total testosterone (TT), 17 alpha-hydroxyprogesterone, dehydroepiandrosterone sulfate, and fasting insulin and glucose levels. Two-tailed t and Pearson correlation tests were used for statistical analysis. RESULTS Women with PCOS were heavier, and their serum FT, TT and LH levels were significantly higher than in the normals (P < .001, P < .012 and P < .001, respectively). The ovarian stromal area measured by transvaginal ultrasonography was also significantly larger than in the normals (P < .001). Only basal serum insulin levels seemed to correlate positively with the ovarian stromal area in women with PCOS (r = .43 P = .09). CONCLUSIONS Although transvaginal ultrasonography has played an important role in the evaluation of women with PCOS, we could not demonstrate a relationship between the ovarian stromal area and hormonal characteristics of PCOS. Therefore, transvaginal ultrasonography and hormonal parameters must be used as complementary diagnostic methods in women with PCOS.