Pregnant, Labs Show Normal TSH And T3 But Increase In Total T4 And T3. Normal?

Posted on Fri, 24 May 2013

Medically reviewed by Ask A Doctor - 24x7 Medical Review Team

Fri, 24 May 2013 Answered on

Tue, 11 Jun 2013 Last reviewed on

Question : My tsh is normal, ft3 is normal, but my total t4 is 15 and total t3 is 2.69 ng/ml. I am also 20 weeks pregnant. Is this normal or considered hyperthyroidism? Please kindly advice..

Answered by Dr. Jorge Brenes-Salazar (1 hour later)

Dear patient,

Thanks for your health concerns. During pregnancy, the total amount of thyroid hormone is relatively increased as part of fetal requirements comes from the mother but free hormones tend to remain normal.

Most importantly, TSH is the main indicator of the thyroid axis; if it is normal, it indicates that levels of hormones are adequate to XXXXXXX normal metabolic needs. To be compatible with hyperthyroidism, TSH would have to be suppressed or undetectable, which is not your case.

Hope this helps, wish you the best health.

Dr Brenes Salazar MD
Cardiovascular Diseases
Mayo Clinic MN

Above answer was peer-reviewed by : Dr. Shanthi.E

Follow up: Dr. Jorge Brenes-Salazar (39 minutes later)

Thanks so much for ur prompt reply.

But even with my total t3 and total t4 is elevated?

Im just worried.. Please kindly advice..

Thank you

Answered by Dr. Jorge Brenes-Salazar (14 hours later)

Hi,

Thanks for writing back.

During pregnancy, the production of the protein that binds (carries) the thyroid hormone, thyroglobulin binding protein, is increased and therefore total T3 and T4 are increased but free levels of hormone are normal and a normal TSH reflects normal thyroid function. That total increase in hormones is normal pregnancy change.

Hope this is useful, wish you the best health,

Dr Brenes Salazar

Above answer was peer-reviewed by : Dr. Raju A.T