Definition

The thyroid gland, located in the lower neck, produces hormones essential for energy metabolism, temperature regulation, and organ function. Thyroid hormones impact nearly every organ in the body, including the heart. If the body lacks sufficient thyroid hormone, certain functions may slow down. Conversely, excessive thyroid hormone can cause body processes to accelerate.

The pituitary gland in the brain controls the thyroid by producing Thyroid Stimulating Hormone (TSH). TSH signals the thyroid gland to regulate hormone production. Abnormally high or low TSH levels may indicate thyroid issues.

For newborns, a TSH test is conducted between 48–72 hours after birth as part of a routine screening for congenital hypothyroidism.

Indications

The neonatal TSH test is performed 48–72 hours after birth alongside other initial blood tests. This screening aims to diagnose congenital hypothyroidism early, preventing potential neurodevelopmental disabilities and optimizing the baby’s growth and development.

It is a standard procedure included in newborn screenings to identify and treat hypothyroidism at birth.

Contraindications

There are no specific contraindications for neonatal TSH screening, as it is a routine part of newborn care.

Preparation Prior to Test

No special preparation is required before a neonatal TSH examination. The test is typically conducted 48–72 hours after birth as part of routine newborn screening.

Test Procedure

The neonatal TSH test involves collecting a blood sample from the baby's heel. The laboratory technician cleans the skin with an antiseptic or alcohol swab, then pricks the heel with a sterile needle to collect blood into a vial or tube. The sample is then processed and analyzed using specialized equipment in the laboratory. Results may take a few days to become available.

Normal and Abnormal Values

Normal TSH levels depend on the baby’s age at the time of testing:

• At birth (Cord blood): 2.2 to 10.7 mU/L
• Age 1 to 4 days: 2.7 to 26.5 mU/L
• Age 4 to 30 days: 1.2 to 13.1 mU/L
• Age 1 to 12 months: 0.6 to 7.3 mU/L
• Age 1 to 5 years: 0.7 to 6.6 mU/L

Abnormal values are those below or above the normal range. Test result ranges may differ slightly depending on the laboratory and methods used.

Results and Recommendations (Follow-up Tests)

Elevated TSH levels may indicate congenital hypothyroidism. Babies with positive results require additional testing to confirm the diagnosis. If congenital hypothyroidism is confirmed, a referral to an endocrinologist is made for further treatment.

This condition, though rare, can be life-threatening if untreated. Affected infants often require extended hospital observation and specialized therapy.

Consult the Right Doctor

If neonatal TSH results are abnormal, consulting a pediatrician or endocrinologist is essential to obtain an accurate diagnosis and begin appropriate therapy.

Looking for more information about laboratory, radiology, and other examination results? Click here!