Congenital hypothyroidism (CHT) is a condition resulting from an absent or under-active thyroid gland or one that cannot make thyroid hormone because of a ‘production line’ problem. The term 'congenital' means that the condition is present at birth. Untreated, it can result in developmental problems and a decrease in intelligence quotient (IQ).

Content overview

Causes

Symptoms

Diagnosis

Treatment

Are there any side effects?

Follow-up

Long-term outlook

Further information

 

Causes

Sometimes the thyroid gland:

• Does not develop in the unborn baby
  
  
• Is in the wrong position and does not work well
  
  
• Is in the right position but does not produce thyroxine normally (a ‘production line’ problem)

Symptoms

Sometimes there may be no obvious symptoms which is why testing at birth is so important. But some babies with CHT may have the following symptoms

• Sleepy and difficult to feed
  
  
• Constipation
  
  
• Cold hands and feet
  
  
• Low muscle tone (floppiness)
  
  
• Poor growth
  
  
• Prolonged jaundice 

Diagnosis

• All babies born in the UK are screened for CHT using a newborn blood spot test usually performed by midwives about four to five days after birth (also known as the heel prick test or Guthrie test)

Treatment

• Levothyroxine in tablet or liquid form
  
  
• The dose will be adjusted as the child grows
  
  
• It is important to take the tablets regularly and on the same schedule
  
  
• Your baby should be managed by a paediatric endocrinologist or a paediatrician with a special interest in endocrinology

 

Are there any side effects?

• Too much levothyroxine may cause irritability, mild diarrhoea, or poor weight gain.
  
  
• Too little levothyroxine over a significant period of time may cause lack of energy, constipation, cold extremities, unexpected weight gain or slow growth

 

Follow-up

Blood tests are carried out:

• Every few weeks during the first few months of life
  
  
• Every three to six months during infancy and childhood

 

Long term outlook

• Levothyroxine will usually be needed for life
  
  
• The vast majority of babies diagnosed with CHT and treated from birth will grow up normally

Further information

Read our guide to congenital hypothyroidism 

Read about thyroid disorders in children

Read about thyroid disorders in teenagers

Find information about treatments for hypothyroidism

Useful resources (films, patient stories, articles, events, phone support etc.)

Please help us help others

With your support we can help people to live better with thyroid disease. Your donations also fund vital research to improve treatments.

Please consider making a donation or becoming a member

Donate to BTF

Become a BTF member