In one study conducted at Virginia Commonwealth University, 24 obese PCOS women were given
metformin or placebo. The 11 women who received the
metformin experienced a reduction in insulin levels, which slowed the activity of an enzyme in the ovaries that stimulates excess production of testosterone. As a result, testosterone levels also dropped.(3)
Glucophage appears to do the same for non-obese PCOS women, according to a study from the University of Medical Sciences in Poznan, Poland.