I-131 myth bursting: association of pregnancy/infertility related adverse effects of radioactive iodine I-131 administration

Abstract

Background: There is very little knowledge on the risks of genetically transmissible diseases after the exposure to radiation. This study aimed to investigate the influence of radioiodine [radioactive iodine therapy (RAI)] on the outcome of pregnancies and the health status of children born to mothers who had received therapeutic doses of I-131 for differentiated thyroid carcinoma or for hyperthyroidism. Methods: Gestational histories of 300 women who were treated with radioactive iodine either for the treatment of hyperthyroidism or for the treatment of thyroid cancer from 2012 to 2017 were retrospectively analyzed. Two Groups were made on the basis of administered doses of radioactive iodine. The first group was further divided into two sub groups. Sub group A consisted of the patients who were treated with radioactive iodine for hyperthyroidism with less than 30 mCi. Sub group B had patients of differentiated thyroid cancer that had been treated with doses above 100 mCi of I-131. Group 2 had patients with primary hypothyroidism and was on thyroxine replacement therapy. Control group consists of healthy young women with no comorbid delivered babies in this time interval. Results: The outcome of the 200 patients were as follows: 97 live births in the group A and 10 miscarriages, while in high dose group, 85 live births and 8 miscarriages were recorded versus 44 live births and 6 miscarriages in the group who were primary hypothyroid. In the control group, there were 50 patients who had 3 miscarriage and 47 healthy babies. Conclusion: Therefore, the present study concluded that radioactive iodine administration does not increased a women risk of infertility or early pregnancy failure.