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Estrogen and the Thyroid?

By , About.com Guide

Updated June 19, 2006

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Question: Estrogen and the Thyroid?
Answer: What about thyroid hormone and estrogen? (i.e., hormone replacement therapy, birth control pills)?

Women taking estrogen (either as hormone replacement -- i.e., Premarin -- or in birth control pills) may need to take more thyroid replacement hormone. Estrogen increases the body's production of a blood protein that binds thyroid hormone to it, making it inactive. For women without thyroids in particular, this can cause a need to increase the dosage level slightly, as there is no thyroid to compensate. After beginning any estrogen therapy, a woman should always have TSH tested to see if the estrogen is having an impact on overall TSH and thyroid function and might require a dosage adjustment.

For more information, see http://thyroid.about.com/cs/drugdatabase/f/estrogen.htm.

FOR MORE INFORMATION ON THYROID DRUGS

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