Thyroid testing

Clinically significant thyroid dysfunction affects cycles, fertility and miscarriage risk, which is why TSH is in Filia’s catalog with free T4 reflexed when TSH falls outside the laboratory range.

The commonly quoted “TSH under 2.5 to conceive” target is more contested than it sounds. ASRM’s 2024 guideline found insufficient evidence that treating a TSH between 2.5 and the upper limit of normal improves fertility outcomes in women without thyroid disease. Filia therefore routes an abnormal TSH to clinician review and reflex testing rather than applying a universal optimal threshold. TPO antibodies can indicate autoimmune (Hashimoto’s) activity when TSH looks normal, but a positive result on its own does not mean treatment is warranted.