The aim of the study is to assess the relationship between the concentration of bisphenol A in serum and selected parameters of thyroid function in women of reproductive age with thyroid dysfunction - Hashimoto's disease and Graves' disease.

Inclusion Criteria:

• Graves' disease or Hashimoto's disease (positive thyroid autoantibody)
• Control group: thyroid autoantibody negative, normal thyroid function
• Women aged 18 to 45 in both the control group and experimental group

Exclusion Criteria:

• Pregnancy and lactating women
• Previous or planned treatment with 131I or thyroidectomy
• The use of drugs affecting the thyroid function (lithium, amiodarone, interferon a, sodium nitroprusside, sunitinib, sorafenib, iodine contrast, antibiotics / antifungals / antivirals (for at least 4 weeks prior to recruitment to the study), which do not result from the treatment of thyroid disease (levothyroxine, thyreostatic drugs, glucocorticoids)
• Active malignancy
• Other autoimmune diseases
• Other endocrine diseases
• Patients with severe liver, kidney or heart failure

Women in the reproductive age from 18 to 45 years of age will be qualified to the study group. Women will be recruited from among patients admitted to the University Hospital in Krakow. After qualifying for the study, each patient will be collected demographic data, information about medical history and medications, as well as anthropometric data.During the medical visit, patients will be presented with all information about participation in the study and only those who give their informed consent in writing will be qualified for the study. Based on the clinical picture and the results of laboratory tests (the level of TSH, fT4 in the plasma and the presence of thyroid autoantibodies), the patients will be divided into 2 groups - 30 women with hyperthyroidism, 30 women with hypothyroidism. 20 healthy women without any thyroid dysfunction will be the control group. The groups will be matched according to age, body mass index and smoking.