Leptin, polycystic ovaries and polycystic ovary syndrome.

As soon as leptin was discovered four years ago, its potential as a player in the polycystic ovary syndrome (PCOS) was explored in a primitive way, though little light was shed on the enigma that is PCOS. As a second wave of leptin research is now available, we review how the expanded role of the cytokine in reproduction might yet impact upon our understanding of PCOS.