Background: Differentiated thyroid cancer occurs in about 1 in 1,000 of pregnant women. Some studies show that during pregnancy increase the risk of thyroid cancer. But those works are quite controversial about long-term follow-up. We have no any firm recommendations in determinations of therapeutic strategy. Methods: We analyzed long-term results of treatment of 33 patients with papillary cancer, revealed during pregnancy. Control group: 23 female patients of similar age, who were not pregnant. Mean age was 25 ± 2.7 years and 23.8 ± 6.6 years. Follow-up period was 21.7 ± 11.5 years and 26.3 ± 14.8 years. These parameters are statistically matched. Results: Mean tumor diameter was 2.3 ± 1.7 cm and 1.8 ± 1.1 cm, regional metastases were revealed in 26 (78 %) and 17 (74 %) of cases. Five (15 %) pregnant patients were operated on during the second trimester of pregnancy, 24 (73 %) up to 22.6 months after delivery, and 4 (12 %) women were operated after an abortion. Operation types: thyroidectomy—5 (15 %) and 5