Hypothyroidism - Wellness Practices of America

TSH is detectable at levels of 3 to 4 mU/L at gestational age 12 weeks and increases moderately over the last two trimesters to levels of 6 to 8 mU/L (8,9).The maturation of the negative feedback control of thyroid hormone synthesis is observed by approximately mid-gestation (Figure 1), with elevated serum TSH concentrations being observed in hypothyroid infants as early as 28 weeks (8). ................
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