Hello, Thanks for the query. There is no mention of which disease related to thyroid you have and what was the reason for checking IgM antibodies. If one has any of the autoimmune thyroid disease there may be an increase in in the immunoglobulins. But increased levels of Igs does not have much of a significance. In conditions like Grave s disease, acute thyroiditis and Hashimoto s thyroiditis there may be an increase in the Igs. Please let me why are looking at this parameter? As in the treatment or control of thyroid conditions there is no role for Igs. There are specific treatments needed for each of the thyroid conditions. Are you on any specific treatment of any of the above mentioned thyroid related conditions? If you have consult a doctor then endocrinologist is the one. Thanks.