The principal objective of this study therefore was to use GCs from small antral follicles to investigate (i) the expression profile of receptors for the key regulatory hormones implicated in follicle arrest in PCOS, focusing on LHCGR and FSHR; (ii) the differences between PCO and control GCs in gonadotropin-responsive steroidogenesis in vitro; and (iii) the differential expression of TGF-β growth factors (particularly AMH) in hSAFs. The gene discussed is AMH; the disease is polycystic ovary syndrome.