GAD2 and polycystic ovary syndrome: One study addressing this issue evaluated the prevalence of anti-glutamic acid decarboxylase 65 (anti-GAD65) and anti-insulinoma-associated antigen-2 (anti-IA2) autoantibodies in pregnant women with gestational diabetes mellitus (GDM), normal pregnancy, and PCOS to assess whether GDM in PCOS is partially induced by autoantibodies.