Stable iodine intake is an essential preventive strategy against thyroid cancer following a nuclear disaster. However, the rate of stable iodine intake during pregnancy and thyroid outcomes among their children have remaifned unclear.

This observational study used data from a thyroid screening program at Research Institute of Radiation Safety for Disaster Recovery Support in Fukushima, Japan. The participants were children from Miharu Town, which implemented stable iodine intake during the Fukushima Nuclear Disaster, born between March 15, 2011 and March 31, 2012. Thyroid ultrasound results were stratified according to stable iodine intake.

This study included 86 children born after the disaster. A total of 34.9% (30 of 86) of their mothers reported taking stable iodine during pregnancy. As for thyroid screening outcomes, none of the children required detailed thyroid examination.

The intake rate of stable iodine during pregnancy was about 1/3 within the traceable municipality after the Fukushima Nuclear Disaster, which was lower than the previously reported number of 63.5% among children. Awareness-raising and effective communication toward pregnant women would be important for nuclear disaster preparedness. There were no participants who required further thyroid examination in this study.