 We also assumed a 10 drop-out rate, and thus aimed at including 50 women. As drop-out rate quickly rose higher than expected, we decided to include 60 women. In the intention-to-treat analysis, the values of each participant after 6 months of metformin or placebo were compared with the baseline values. Linear regression analysis with the changes in testosterone and homeostasis model assessment HOMA index as dependent variables was performed to examine potential relations between the changes. The per protocol analysis included data from participants completing both study periods, i.e. the difference between the values of each participant after placebo and metformin, respectively, was calculated, and a significance test performed on the differences. 