AIM: The present paper investigates the relationship between polycystic ovary syndrome, hypothyroidism and insulin-resistance and how, by submitting patients to a specific therapy for any one of the three pathologies, we also obtain an improvement in the other associated pathologies. METHODS: We selected 45 patients aged between 16 and 25 with problems of polycystic ovary syndrome, hypothyroidism and insulin-resistance and divided them into 3 groups. The 15 Group A patients followed a dietetic therapy. The 15 patients of Group B received hormonal therapy. The 15 Group C patients received replacement therapy with laevo-thyroxine. All patients had their thyroid and ovary function checked every six months and a glycoinsulinaemic curve was plotted after glucose loading. RESULTS: A reduction in TSH levels and an increase in the values of circulating thyroid hormones was observed in all patients. The ovary situation underwent both a hormonal and symptomatological improvement with diminution in LH and testosterone levels and an increase in progesterone. The glucose-insulin picture of our patients progressively improved in all 3 groups studied. CONCLUSIONS: The data obtained in our study enable us to support the close connection between ovary function, thyroid function and insulin-resistance. In all patients, in fact, albeit at different times, an improvement was obtained in all 3 pathologies.