Since then,treatment of PCOS patients with the TZDs rosiglitazone or pioglitazone havebeen shown to not only improve insulin action in peripheral tissues, attenuatehyperinsulinemia, and lower circulating levels of lipids [92, 94], but also toimprove a range of reproductive outcomes particularly circulating sex hormonelevels, and ovulation rate [77, 88, 90, 95–97] (see recentreports summarised in Table 2). This evidence concerns the gene INS and polycystic ovary syndrome.