All these three conditions can exist with or without the presence of thyroid autoimmunity marked by autoantibodies such as those against thyroid peroxidases (TPOAb +) or thyroglobulin (TgAb +). There is no doubt that overt hypothyroidism should be promptly diagnosed and treated with levothyroxine in order to prevent severe maternal and fetal consequences such as fetal loss, premature birth, neurocognitive impairment of the child (1). The gene discussed is TPO; the disease is autoimmune thyroid disease.