What is hypothyroidism?

Hypothyroidism is a condition in which the thyroid gland is underactive and produces an insufficient amount of thyroid hormone. Hypothyroidism is the most common thyroid disorder affecting children, and its most common cause is known as Hashimoto’s thyroiditis, which is an autoimmune disorder.

Children with hypothyroidism display different symptoms from adults with the disorder. A mother’s hypothyroidism or the treatment of her hypothyroidism while pregnant can sometimes cause her baby to develop this condition. Hypothyroidism in the newborn, when left untreated, can lead to intellectual disability and profound developmental delays. It is also associated with an increased risk for abnormalities of the cardiovascular, urogenital and skeletal systems.

What are the symptoms of hypothyroidism?

Because hypothyroidism in newborns is so dangerous, all newborn infants should be screened for low thyroid function. If hypothyroidism at birth is left untreated, it can result in a wide array of symptoms, including jaundice, a hoarse cry, poor appetite, umbilical hernia, constipation and slow bone growth. In older children, hypothyroidism can result in slow growth, delayed tooth development and fatigue. In adolescents, symptoms include fatigue, feeling cold, constipation, delayed puberty, hoarse voice, slow speech, droopy eyelids, moderate weight gain and more.

How is hypothyroidism diagnosed?

Most cases of newborn hypothyroidism are detected during routine newborn screening. In older children, blood samples may reveal abnormal hormone levels that suggest thyroid problems. Specialists may also perform a scan of the thyroid gland to ensure it is healthy.

How is hypothyroidism treated?

Each patient is different, and the most effective treatment plan involves coordination between the child’s health care team, the child and the child’s family.

Treatment may include taking medications with thyroid hormones to replace the deficient hormones. Some children will require hormone replacement therapy for the rest of their lives while others may outgrow the disorder. Regular monitoring of the child's thyroid hormone levels during the course of treatment can help your child's doctor manage your child's condition more accurately.