If your baby tests positive for hypothyroidism, their condition should be managed by a paediatric endocrinologist or a paediatrician with a special interest in endocrinology. They will immediately treat your baby with levothyroxine, which is synthetic thyroid hormone. This is a replacement for the thyroxine that their body isn’t able to produce naturally. The dose is carefully calculated based on the weight of your baby and will be adjusted regularly as your baby grows. Your baby will be given blood tests every two to three months during the first year of their life and then every four to six months during infancy and childhood, usually until they are 18. These tests will check your child’s levels of thyroid hormone and TSH. The amount of levothyroxine that your child needs to take will be adjusted depending on the results of these tests.

When your child reaches adulthood and their treatment is stable, they will normally have a blood test once a year and be placed under the care of a GP.

Most children diagnosed at birth will need to take levothyroxine for life. They will be tested regularly as the amount they will need to take will change as they grow. It is important to monitor your child’s medication as you will need to make sure that they take it regularly.