Effect of troglitazone on endocrine and ovulatory performance in women with insulin resistance-related polycystic ovary syndrome

Objective: To investigate the effect of troglitazone, a new antidiabetic agent that improves insulin resistance, on endocrine, metabolic, and ovulatory performance in women with insulin resistance-related polycystic ovary syndrome (PCOS). Design: Prospective clinical study. Setting: Infertility outpatient clinic, Niigata University Hospital, Niigata, Japan. Patient(s): Thirteen women with PCOS and insulin resistance. Intervention(s): Troglitazone (400 mg/d) was administered for 12 weeks. Main Outcome Measure(s): Insulin and other hormone (gonadotropins, androgens) levels; various parameters relating to glucose and lipid metabolism before, during, and after troglitazone administration; and ovulation rate. Result(s): The mean (+/-SD) fasting insulin concentration was significantly reduced, from 18.3 +/- 8.9 to 10.5 +/- 7.1 mu U/mL. The LH level was reduced from 9.7 +/- 3.4 to 4.8 +/- 3.9 mIU/mL and the testosterone level was reduced from 0.9 +/- 0.5 to 0.5 +/- 0.3 ng/mL in accordance. Atherosclerotic lipid levels also were normalized. Before troglitazone administration, the ovulation rate during clomiphene citrate therapy was 34.9% per cycle (15/43). This increased significantly to 72.7% (8/11) during troglitazone coadministration. Further, an ovulation rate of 42.3% (11/26) was achieved with troglitazone alone. Conclusion(s): In women with PCOS and insulin resistance, the reduction of hyperinsulinemia that is produced by troglitazone improves the hyperandrogenism that characterizes PCOS, restoring ovulation. (Fertil Steril(R) 1999,71:323-7. (C) 1999 by American Society for Reproductive Medicine.)