Newborn grandson diagnosed with hypothyroidism.

Encourage your friend, it is good this was found early, with proper treatment there should be no adverse effects. Some infants will outgrow this in a few months, but still need to be treated, don't let your friend wait to have her baby treated, the first month is critical.

Hypothyroidism in infants and children, while relatively rare -- approximately 1 in 4,000 infants have the condition-- poses a serious threat to a child's physical and mental development if left untreated.

Hypothyroidism can affect both newborns and older children, and occurs for a variety of reasons, but the treatment is always the same.

There are different types of hypothyroidism in infants/children, methods for detection and treatment, and why it is crucial that your newborn be tested within the first few days of birth. In some extremely rare instances, hospital tests can be faulty. Some symptoms to watch for if you suspect a faulty test:

Puffy face, swollen tongue
Hoarse cry
Cold extremities, mottled skin
Low muscle tone (floppy, no strength)
Poor feeding
Thick coarse hair that goes low on the forehead
Large fontanel (soft spot)
Prolonged jaundice
Herniated bellybutton
Lethargic (lack of energy, sleeps most of the time, appears tired even when awake)
Persistent constipation, bloated or full to the touch
Little to no growth

Early diagnosis is very important. Most of the effects of hypothyroidism are easily reversible.

Replacement therapy with thyroxine is the standard treatment of hypothyroidism. Once medication starts, thyroid blood tests are regularly done to make sure levels are within a normal range.

Very early diagnosis generally results in a good outcome. Newborns diagnosed and treated in the first month or so generally develop normal intelligence.

Untreated, mild hypothyroidism can lead to severe mental retardation and growth retardation. Critical development of the nervous system takes place in the first few months after birth. Thyroid hormone deficiency may cause irreversible damage.