INS and Insulin resistance: The primary objective of this randomized controlled trial is to evaluate the hypothesis that true acupuncture + metformin placebo (group 1) improves insulin sensitivity, as measured by changes in the homeostasis model assessment of insulin resistance (HOMA-IR), more effectively than sham acupuncture + metformin (group 2) and sham acupuncture + metformin placebo (group 3) in women with PCOS and IR.