How fast do tsh levels and t4 levels rise in the first trimester of pregnancy? my levels were checked at 4.5 weeks. tsh was .33. t4 was 1.5. i am now 6 weeks pregnant. i am on synthroid 112mcg due to a total thyroiectomy in 2008. they will be re-chec

Not : Not every pregnant woman needs an increase in thyroid hormone during pregnancy. In general, those without any thyroid left (that includes you) do need an increase and more of an increase than others. We usually would want to wait about 6 weeks before being sure you need to increase further after a previous increase since it takes that long to stabilize on a given dose. There is some controversy about just how important it is to keep the TSH perfect during pregnancy. Some recent data challenge the concern that a slightly increased TSH poses risk to the baby. Waiting 2 weeks to re-test is fine. Sounds like your doctor is watching you closely and that's good. Mom's can learn from what happened in previous pregnancies as to what to do with their thyroid dose the next time they get pregnant.

Need : Need not to worry. Your free T4 level is good (aim for high end of the normal reference) and checking it in 2 weeks to reasonable. Typically, the dose of synthroid (thyroxine) for women who are preganant is increased by 10-20% due to increased demand (fetus) so if your dose has not changed so far, your next appointment with repeat labs should be the perfect timing to discuss such approach. Good luck and congratulations. Cayce t. Jehaimi, M.D., faap pediatric endocrinology & diabetes the children's hospital of southwest florida fort myers, fl usa.