New onset of Graves' disease after controlled ovarian stimulation: A case report and brief literature review

De novo onset of Graves' disease (GD) after controlled ovarian stimulation (OS) is exceptional. Only one case of progression to GD after OS in a patient with pre-existing subclinical hyperthyroidism has been reported. We describe the case of a patient with neither previous thyroid disorders nor autoimmunity who developed GD after OS for primary infertility. A 40-year-old woman with primary infertility underwent four cycles of OS. Her thyroid function performed before the last cycle was unremarkable (thyroid stimulating hormone [TSH] 1.9 mU/L, fT4 1.3 ng/dL, fT3 2.4 pg/mL), and thyroid autoimmunity was negative (anti-thyroperoxidase antibodies and anti-thyroglobuline antibodies). Six weeks after the last cycle she developed overt thyrotoxicosis (TSH < 0.005 mU/L, fT4 4.79 ng/dL, fT3 15.6 pg/mL) with anti-thyrotropin receptor antibodies (TRAb) positivity (9.2 IU/L). She was diagnosed with GD and anti-thyroid therapy was instituted. After 1 year of treatment, thyroid function was still suboptimal (TSH 0.2 mU/L, fT4 1.04 ng/dL, fT3 2.2 pg/mL), and TRAb titer still elevated (8.75 IU/L). Despite her desire to achieve pregnancy, a further cycle of OS was postponed until complete remission of thyroid dysfunction and withdrawal of anti-thyroid therapy. Although TSH assay after OS is not recommended in euthyroid women without autoimmunity, in the presence of hyperthyroid symptoms throughout OS it is advisable to evaluate thyroid function and TRAb. It is advisable to carefully evaluate the course of GD before proceeding with further courses of OS that could lead to its exacerbation or recurrence. In cases where a strong desire for pregnancy persists, thyroidectomy may be proposed.