How should treatment for hypothyroidism change while pregnant?

Mary Chappell
OBGYN (Obstetrics & Gynecology)
Thyroid medication needs can increase during pregnancy as weight and plasma volume increase.  I check my patient's thyroid levels pre pregnancy if possible to be in good control at conception.  I then check a free T4 every trimester and adjust meds accordingly.  TSH levels are not accurate in pregnancy due to cross reactivity with the pregnancy hormone HCG.  You must check free T4.  Under controlled thyroid can cause mental development delays in children so it is VERY important to stay on your thyroid meds and adjust them as needed!
Dr. Mehmet Oz, MD
Cardiology (Cardiovascular Disease)
In pregnancy, women who start out with hypothyroidism typically need to increase their thyroid hormone dosages by 50 percent because the increased estrogen produces an increased level of a protein that binds thyroid hormone - meaning even less thyroid hormone will be available for the mother.
YOU: Having a Baby: The Owner's Manual to a Happy and Healthy Pregnancy

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YOU: Having a Baby: The Owner's Manual to a Happy and Healthy Pregnancy

Can I get a cavity filled while pregnant? Will avoiding spicy foods make my kid a picky eater? Can I really increase my baby's IQ while she's in utero? Whether you're pregnant for the first time,...

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Important: This content reflects information from various individuals and organizations and may offer alternative or opposing points of view. It should not be used for medical advice, diagnosis or treatment. As always, you should consult with your healthcare provider about your specific health needs.