Neonatal thyroid values are mainly the five thyroid function tests. Normal values vary clinically, so reference ranges need to be determined based on the test reagents. Specifics need to be determined by the clinician in conjunction with the baby’s clinical presentation.
They include triiodothyronine reference value of 1.5-2.7nmol/L, free thyronine reference value of 3.6-10.4ρmol/L, total thyroxine reference value of 45-224nmol/L, free thyroxine reference value of 11.2-27.3ρmol/L, and thyroid-stimulating hormone reference value of 0.2-7.1mlU/L.
However, clinically, the test results of different reagents have some differences, so all of the above are reference values, within which can be clearly considered normal, but outside of this range, need to be handled under the guidance of a doctor.
Generally, newborns will be screened for thyroid function within 72 hours of birth to prevent congenital hypothyroidism caused by insufficient synthesis of thyroid hormone. If the screening result is abnormal, a complete set of thyroid function can be reviewed to assist in the diagnosis and early intervention, followed by regular review and adjustment of the use of medication to avoid the occurrence of cretinism in young children.