Is it necessary for TSH levels to be below 2.5 mIU/L when preparing for pregnancy?
My partner and I are currently trying to conceive, and I learned that there are reference values for thyroid-stimulating hormone (TSH). During my recent physical examination, this indicator was slightly elevated, which has made me quite anxious. I would like to ask, is it necessary for this value to be strictly below 2.5 mIU/L?
Doctor's answer (1)
For most individuals planning pregnancy, if thyroid antibody levels are normal, TSH levels are generally recommended to be below 3.0 mIU/L during pregnancy planning or the first trimester. However, if thyroid antibody levels are elevated, whether TPO antibodies or TgA antibodies are increased, to promote fetal neural tube development and achieve the goal of improved birth outcomes, TSH should be controlled below 2.5 mIU/L.
Thyroid-stimulating hormone (TSH) levels should be maintained within a more optimal range to reduce the risk of pregnancy complications, such as miscarriage, preterm birth, and low birth weight. Individual differences should be considered—for example, patients with a history of autoimmune thyroid disease may require stricter target values.
Therefore, it is recommended that women planning pregnancy undergo a comprehensive thyroid function evaluation, including tests for TSH, free T4, and anti-thyroid antibodies, and adjust treatment plans based on the results. In addition, regular monitoring and timely adjustment of treatment strategies help maintain stable thyroid function and ensure maternal and fetal safety.
