The Process Of Screening Newborns For Hypothyroidism

Infants with Congenital Hypothyroidism (CH) may look normal and not exhibit any detectable physical symptoms. CH is caused by low production of thyroid hormone, which forms an important component of the endocrine system. This network of glands coordinates most of the body's functions including brain functioning. When CH is not detected and treated early, it can lead to severe outcomes, such as mental retardation and learning disabilities. Due to this, neonatal screening is emphasized within two weeks after birth. How is this screening process carried out? Below is a simple outline of all the steps.

Newborn screening

Newborn screening describes the process through which infants are tested for certain serious conditions that are treatable. The doctor will collect a blood sample from your baby 24 hours after birth from a heel prick to avoid getting a false positive resulting from the TSH surge that occurs immediately after delivery. If the blood sample shows out of normal range results for CH, your doctor will contact you and arrange for additional testing. Do not panic upon receiving this news because positive results might occur when a blood sample is too small. However, make sure you take the baby for the followup appointment immediately because CH causes harmful effects soon after birth.

Blood test

Once you take the baby to the doctor, the first confirmatory test is the blood test. The doctor will collect a capillary sample from the baby and put it on one side of a special filter paper that is designed to screen newborns for CH. This paper has printed circles where the blood samples are placed and expected to fill and saturate the whole area.  Any paper with double spotting will give invalid results and cannot be used for screening. All valid specimens used contain a sufficient amount of blood and are dried at room temperature. If your child has a TSH concentration of more than 40 mU/Ls and a low T4 concentration, they are considered to have CH.


After getting positive results for hypothyroidism, your doctor will recommend a thyroid imaging test to ascertain the cause of this condition. In most cases, CH is caused by an abnormally small, or a misplaced or missing thyroid gland.  Most doctors use an ultrasound to locate and determine presence of thyroid tissue in babies.


Treatment of CH will commence immediately after the doctor ascertains its presence and cause. Your baby will be given L-thyroxine pills, which contain a synthetic thyroid hormone that will cater for the deficit that the body is unable to produce. This replacement therapy will continue throughout your child's lifetime. In addition, your child will have regular checkups to monitor thyroid levels, as well as their mental growth and development.