What is Congenital Hypothyroidism?

Congenital hypothyroidism

Congenital hypothyroidism is a condition that can affect newborn babies. The word congenital means present at or before birth, while hypothyroidism refers to insufficient levels of thyroid hormone. While congenital hypothyroidism is a serious condition, it can generally be detected and treated early enough to prevent complications, thanks to routine screenings after birth in many parts of the world.^[1][2][3]

The thyroid is a small, butterfly-shaped gland found in the lower part of the neck, just below the voice box. Hormones released by the thyroid control the body’s growth and metabolism. They affect key physical processes like heart rate, digestion, weight, and temperature.^[4] Adequate levels of thyroid hormone are essential for the healthy physical and mental development of a baby.^[2]

Congenital hypothyroidism affects approximately one in every 2000 to 4000 newborns^[5] and has been found to be more common in female babies.^[1] The condition occurs when the baby’s thyroid gland does not develop or function properly. In the majority of cases, the gland itself is absent, smaller than normal, or located in the wrong place. However, congenital hypothyroidism may also result when the gland is normal, but there are problems with the production of thyroid hormone.^[6]

In the USA, UK, and many other parts of the world, all newborn babies are screened for congenital hypothyroidism within a few days of birth. A simple heel-prick blood test is typically used, and if the results suggest the presence of congenital hypothyroidism, further tests will be done to confirm the diagnosis. Where necessary, treatment with synthetic thyroid hormone will be started without delay.^[1][2][6][7]

If left untreated, congenital hypothyroidism can lead to severe, irreversible mental impairment and poor growth. However, with prompt, proper treatment and monitoring, the prognosis is excellent, and infants with congenital hypothyroidism will usually grow up to lead normal, healthy lives.^[1][2][6][8]

Congenital hypothyroidism symptoms

Most newborn babies with congenital hypothyroidism show no obvious signs of the condition.^[5] This may be because they receive some of their mother’s thyroid hormones before being delivered. They may also be able to produce a small amount of their own.^[1][8]

However, some babies affected by congenital hypothyroidism may be less active, sleep a lot and be difficult to feed.^[6][9] If congenital hypothyroidism is severe, the following signs and symptoms may also be present:^[1][2][5][9]

• Weak cry
• Poor feeding
• Constipation
• Dry skin
• Poor muscle tone (floppiness)
• Cold hands and feet – they may also be mottled
• Prolonged jaundice, which is when the skin has a yellow color
• Puffy face
• Large tongue
• Swollen stomach
• Umbilical hernia
• Large fontanels, which are the soft spots on a baby’s head

It is important that a newborn baby be screened for congenital hypothyroidism as early as possible in order to prevent complications.

In many countries, babies are screened sufficiently soon after birth that they will generally not have symptoms of congenital hypothyroidism. However, in rare cases, a baby with the condition may have symptoms immediately after birth.^[5]

In parts of the world where screening is not performed, a baby may not show symptoms of congenital hypothyroidism initially, but they will typically develop symptoms in the first few months after birth.^[5] If you are concerned about any symptoms, contact your doctor Find My doctor location.

Congenital hypothyroidism causes

The most common cause of congenital hypothyroidism is the baby’s thyroid gland not developing properly. The gland may be absent, smaller than normal, or positioned in the wrong part of the neck. It is not known why this happens, but the malformation is not usually inherited – meaning that any siblings are unlikely to be born with the same thyroid condition.^[2][3]

Other less common causes of congenital hypothyroidism include:^[1][2][3]

• Problems metabolizing thyroid hormone; this may be inherited
• Problems with the hypothalamus or pituitary gland, two very important, connected parts of the brain that regulate a large number of bodily processes
• Iodine deficiency in the parent during pregnancy, though this is uncommon in developed countries
• High levels of thyroid antibodies^[10] in the parent during pregnancy
• Antithyroid medication taken during pregnancy, in a small number of cases

Excessive iodine intake, congenital liver hemangiomas (non-cancerous growths of blood vessels), and certain gene mutations may also be factors in the development of congenital hypothyroidism.^[11]

Diagnosis of congenital hypothyroidism

In many countries, all newborn babies are screened for congenital hypothyroidism shortly after birth. This is done in the hospital using a pinprick test that draws a small amount of blood, usually from the baby’s heel, to check their thyroid hormone levels. The baby will typically be checked for other conditions such as cystic fibrosis and sickle cell disease at the same time.^[1]

If the baby’s thyroid hormone levels are not within the acceptable range, a doctor will order further blood tests to confirm the diagnosis of congenital hypothyroidism. They may also request a thyroid ultrasound scan to be performed in order to assess the physical status of the thyroid gland. Treatment will be started immediately.^[1][2]

Congenital hypothyroidism treatment

Treatment for congenital hypothyroidism typically involves medication, monitoring, and assessment of the baby’s development.^[3]

Medication

The standard treatment for congenital hypothyroidism is the prescription of synthetic thyroid hormone in the form of levothyroxine (L-T4). In many cases, it will be necessary to take levothyroxine for life, even into older adulthood.^[2][9]

Levothyroxine comes in tablets, which should be crushed and given to the baby in a small amount of water or milk every day. A doctor will advise on the dose needed, as well as what foods to avoid giving the baby before and after taking the medication. It is important not to mix the tablets with soy formula or any preparation containing concentrated iron or calcium. When the child is older, they can swallow the tablets on their own with a cup of water. The dose will need to be adjusted as the child grows up.^[5][9]

Prompt, proper treatment with levothyroxine can generally prevent complications from congenital hypothyroidism. The medication is generally considered safe and has no side effects at the correct dose. If the dose is too low, symptoms of hypothyroidism may develop, while too high a dose can lead to symptoms of hyperthyroidism.^[3]

Monitoring

In many cases, a doctor will recommend working with a pediatric endocrinologist, a specialist in childhood conditions related to hormones, to help manage the baby’s congenital hypothyroidism as they grow up.^[2][3][9]

The baby will need to have regular medical check-ups to make sure that their thyroid hormone levels are adequate for healthy growth and development. Regular blood tests will also be required. Until the baby is one year old, tests will usually be necessary every one to three months or more frequently. Thereafter, it may be possible to reduce the frequency of blood tests. A doctor will adjust the dose of levothyroxine as needed.^[3][9]

Developmental assessment

A doctor will also monitor the height, weight, and overall growth and development of the child.^[3] They will periodically assess the child’s language and communication skills, motor ability, and behavior.^[1] If it seems necessary, a doctor may recommend having the child’s development formally evaluated. Should there be any delays in speech or learning, an early intervention program can often be arranged to assist the child.^[3]

Prevention of congenital hypothyroidism

It is generally not possible to prevent congenital hypothyroidism.^[9] However, pregnant people with a history of thyroid conditions, as well as those taking any medications or supplements, are advised to consult with medical practitioners before, during, and after pregnancy in the interests of optimal health management.

Read about Thyroiditis »

Congenital hypothyroidism FAQs

Other names for congenital hypothyroidism

Congenital hypothyroidism is sometimes also known as:

• CH or CHT
• Underactive thyroid since birth
• Nongoitrous congenital hypothyroidism
• Thyroid hormone deficiency present at birth
• Inborn hypothyroidism
• Cretinism (outdated, pejorative)
• Congenital myxedema

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1. Patient. “Childhood and Congenital Hypothyroidism.” April 17, 2014. Accessed December 11, 2017. ↩ ↩ ↩ ↩ ↩ ↩ ↩ ↩ ↩ ↩ ↩

2. Pediatric Endocrine Society. “Congenital Hypothyroidism: A Guide for Families.” 2014. Accessed December 11, 2017. ↩ ↩ ↩ ↩ ↩ ↩ ↩ ↩ ↩ ↩ ↩

3. Screening, Technology and Research in Genetics. “Congenital Hypothyroidism.” December 12, 2012. Accessed December 11, 2017. ↩ ↩ ↩ ↩ ↩ ↩ ↩ ↩ ↩ ↩ ↩ ↩

4. NHS Choices. “Thyroiditis.” September 19, 2017. Accessed December 11, 2017. ↩

5. UpToDate. “Clinical features and detection of congenital hypothyroidism.” November 14, 2017. Accessed December 11, 2017. ↩ ↩ ↩ ↩ ↩ ↩ ↩

6. U.S. National Library of Medicine. “congenital hypothyroidism.” December 6, 2017. Accessed December 11, 2017. ↩ ↩ ↩ ↩

7. Arquivos Brasileiros de Endocrinologia & Metabologia. “Congenital hypothyroidism: recommendations of the Thyroid Department of the Brazilian Society of Endocrinology and Metabolism.” April, 2013. Accessed December 11, 2017. ↩

8. Orphanet. “Congenital hypothyroidism.” August, 2010. Accessed December 11, 2017. ↩ ↩ ↩

9. British Thyroid Foundation. “Congenital Hypothyroidism.” 2015. Accessed December 15, 2017. ↩ ↩ ↩ ↩ ↩ ↩ ↩ ↩ ↩ ↩

10. Antibodies are immune system proteins which usually attack bacteria and viruses, but can mistakenly attack the thyroid gland or other parts of the body. ↩ ↩

11. Orphanet Journal of Rare Diseases. “Congenital hypothyroidism.” June, 2010. Accessed December 19, 2017. ↩

12. Victorian Agency for Health Information. “Hypothyroidism in neonates.” November 21, 2018. Accessed March 4, 2019. ↩

13. Journal of Clinical Endocrinology and Metabolism. “Transient congenital hypothyroidism and hyperthyrotropinemia: normal thyroid function and physical development at the ages of 6-14 years.” April, 1996. Accessed March 4, 2019. ↩

**Q: What is Congenital Hypothyroidism?**



**A:** Congenital ‍hypothyroidism‍ (CH) ‌is a ⁢rare medical condition in which‍ an infant ⁣is born ‍with an underactive thyroid. The thyroid is a small, endocrine coin-sized organ in ‍the neck that produces two ‌hormones: T3⁤ (triiodothyronine) ‌and T4 ⁤(thyroxine).⁤ These hormones are essential for the growth and development of the brain and nervous‍ system, ⁤especially during the first year of⁤ life.



**Q: What causes ⁣CH?**



**A:**​ Most‌ cases of CH ‍are caused by a thyroid development problem that occurs during pregnancy. In‍ about half‍ of these⁢ cases (found among White and Hispanic ​populations), the thyroid is not formed⁤ or is⁤ in an unusual location (called thyroid ectopy),⁢ fails‌ to secrete hormones (aplasia), or ⁤is damaged by​ a problem ⁢with the immune system⁤ (lymphocytic thyroiditis). The ⁣other half of the time, the cause​ of CH is unknown (sporadically ​cases) but could be from⁣ premature birth. Occasionally, CH can be caused by taking certain types of medication during ‍pregnancy, iodine, and ‌other environmental factors‍ (mostly seen in Asian countries).



**Q: What are ⁢the symptoms ⁢of⁤ CH?**



**A:**⁤ The symptoms of CH can vary depending on the age of the infant and the ⁤amount ​of thyroid‌ hormones that are present. Signs that‍ you might notice in general are:

– In newborns: yellow or yellowish skin (physiological jaundice), poor muscle tone, a hoarse cry, or difficulty ⁢breathing, and slow reflexes may ⁣also be present.

– In ⁤older children: growth failure, delayed motor development, and delayed mental development.



**Q: How is CH ​treated?**



**A:** Treatment for CH involves taking thyroid hormones replacement. Treatment includes taking oral tablet medicine called levothyroxine. This medicine is​ a⁢ synthetic form​ of the ​thyroid hormones that the body is not able to ⁣produce on its own.​ It ⁣is essential to start treatment ​as soon as possible to‍ ensure proper growth ​and development.



**Q: What is the prognosis for CH?**



**A:** With ⁢early diagnosis and treatment, the prognosis for individuals‍ with CH‍ is generally excellent. If the condition ⁣is detected and treated ‍early, most ​children with CH can live ⁤healthy and normal lives. However, if the condition is not detected and treated early, it can‌ lead to a range of serious lifelong problems.⁣ This means that it is ‌important for you and​ your doctor to discuss early ⁢detection of CH to ensure your health.



**Q: Who is recommended ⁢for CH‍ newborn screening?**



**A:** ‌CH screening is generally ‌recommended ‌for all⁤ newborns in the United States regardless⁢ of their birthplace. This ⁤is done ​to ensure that any potential cases of‌ CH can be​ detected and treated early on.



**Q: What⁢ is the treatment goal for CH?**



**A:** The ‌treatment ⁤goal for CH is to maintain normal levels of⁢ thyroid hormones in the body. This is done by taking ​thyroid⁢ hormones replacement medication.



**Q: What is‍ the‍ most common cause‌ of⁣ CH?**



**A:** The‌ most common cause of CH ⁤is a problem with the ⁢formation or development of⁣ the thyroid.