“…Multiple causes must be considered in fetal neck masses investigation, such as cystic hygroma, teratoma, angioma, lymphangioma, and goiter, among others. Thus, imaging exams like US and, when not well clarified, fetal MRI assume a relevant role in clarifying the underlying cause [1, 6, 7]. After the fetal goiter diagnosis, initial assessment should include maternal medication or supplementation, iodine status, thyroid function, and autoimmune thyroid disorders (TSH, fT3, fT4, anti-TPO, anti-TG, and TSH receptor blocking antibodies) [1, 7].…”