Dx: High TSH, Low Free T4
Subclinical: Slight ↑ TSH, Normal Free T4- Treat TSH >15 mU/L
- Don’t Treat <10 mU/L (10-15 mU/L equivocal)
- TSH maybe low or normal
- Non-Pregnant: 0.4 – 4.5 mU/L
- 1st Trimester: 0.1 – 2.5
- 2nd Trimester: 0.2 – 3.0
- 3rd Trimester: 0.3 – 3.0
- Free T4: Use specific lab kit values for pregnancy.
- Total T4: Multiply x 1.5
- Increase L-Thyroxine dose by 1/3 [to avoid miscarriage]