In most of these studies, although not all, higher levels of anti-TPO and/or anti-Tg antibodies were observed, exceeding the upper limit of the normal range in an average of 22.3% of patients with PCOS (ranging from 4.8% to 37.9%, depending on the study), compared with an average of 8.5% in healthy women (range 3.3% to 15.3%). Here, TG is linked to polycystic ovary syndrome.