Effects of maternal exposure to 131-I used for treatment of Graves' disease during childbearing age on chromosomal aberration and intellectual development of offspring

Although radioiodine-131 (131I) has been widely used for the treatment of Graves' disease (GD), radiation is a potential risk factor for mutagenic abnormalities. This retrospective clinical study mainly aimed to investigate the influence of maternal exposure to 131I used for the treatment of GD prior to pregnancy on chromosomal aberration and intellectual development of offspring in China.

In total, 69 children whose mothers received 131I for the treatment of GD during childbearing age were included. Data on the obstetric history, medical records, and the birth characteristics of the children were obtained. The thyroid function, thyroid ultrasound, chromosomal structure, and somatic and intellectual development of the children were measured.

In all 66 women, the range of the administered 131I was within 228.2 ± 70.3 MBq. The height and weight of all children were within the normal ranges, and one child was confirmed as having subclinical hypothyroidism. Two children were diagnosed with benign thyroid nodules, one child was diagnosed with thyroid cysts, and one child was confirmed as having several anechoic areas in both lobes of the thyroid gland. Chromosomal aberration was observed in one child. None of the children showed any abnormalities in somatic and/or intellectual development.

This is the first study to confirm that 131I used for the treatment of GD prior to pregnancy does not significantly increase the risk of chromosomal aberration or impair the intellectual development of offspring.