Thyroid cancer has had an increasing prevalence over recent years and poses an extraordinary challenge when diagnosed during pregnancy. Although in the majority of cases in pregnant patients there occurs a well differentiated papillary carcinoma which has an excellent prognosis and for which surgery can be delayed until the postpartum period, in rare cases of advanced or rapidly growing tumour, and in a case of medullary or anaplastic cancer, surgery should be undertaken during pregnancy. Here, we present the case of a 30 year-old woman with Hürthle cell neoplasm recognised on cytology during the second trimester. Because of the neck lymph nodes metastases diagnosed on ultrasonography and cytology, which also could be seen as calcified foci on a chest X-ray examination performed three years earlier, she underwent surgery before the 22(nd) week of gestation. The course of surgery was successful and uneventful and she delivered a healthy child on term. An approach to pregnant patients with differentiated thyroid carcinoma is discussed.