While it’s less common than in adults, hypothyroidism — an underactive thyroid — affects newborns, babies, children, and teenagers. If you have a personal or family history of thyroid or autoimmune disease, your children are at greater risk of developing a thyroid condition, most often hypothyroidism. Let’s explore the types of hypothyroidism that affect infants and children, the signs and symptoms, and effective treatment.
Congenital hypothyroidism refers to hypothyroidism present at birth. The condition affects an estimated 1 in around 2,000 newborns in the United States each year. Congenital hypothyroidism is more common in Hispanic and Asian — as compared to Caucasian — newborns and is 30 percent less common in African-American babies. It’s estimated that congenital hypothyroidism is 10 times more common in Down syndrome babies.
Congenital hypothyroidism is most often detected during routine, mandatory heel-prick blood screening, usually done in the first few days after a baby is born. In some cases, however, congenital hypothyroidism may not be picked up on a newborn heel stick, but a diagnosis is made when symptoms appear after a baby leaves the hospital.
There are many congenital hypothyroidism symptoms to watch for in your newborn or baby, including:
- Prolonged gestation — your baby was born significantly after his or her due date
- Poor feeding habits
- Puffy face
- Swollen tongue
- Hoarse cry
- Low muscle tone
- Cold extremities, low body temperature
- Delayed first bowel movement
- Persistent constipation
- Lack of energy, and reduced activity
- Excessive tiredness and sleeping
- Slow growth or lack of growth
- Noisy breathing
- Slower-than-normal heart rate
- Large fontanelle (soft spot) on the skull
- Protruding tongue
- Yellowing of the skin and the whites of the eyes
It is crucial to recognize possible symptoms and get congenital hypothyroidism detected and treated right away, to avoid impairments to your baby’s cognitive and physical development.
Cara’s son Ethan was diagnosed with congenital hypothyroidism while she was still in the hospital.
“I had to have a C-section because I was two weeks past my due date, and they induced me, but my labor got stalled. Ethan was born at almost 9 pounds! I was so worried about him because the first day, he was so quiet, slept constantly, and I could not get him to latch on to breastfeed. Something didn’t seem right. I admit I totally freaked out when the doctor told me that Ethan had a thyroid problem and they had found it on the tests. But since then, I read everything I could get my hands on, and got to talk with other moms with hypothyroid babies and learned everything I can. So far, though, it seems like Ethan is doing well. He’s 3, and he’s a normal, happy little boy, thankfully!”
Acquired hypothyroidism, affects 1 in 1,250 children, and the condition becomes even more common after puberty. It’s estimated that about 4.6 percent of the U.S. population age 12 and older has hypothyroidism.
Acquired hypothyroidism refers to children whose thyroid has become underactive due to causes that include autoimmune Hashimoto’s disease, drugs and medical treatment, and radiation exposure. Acquired hypothyroidism is more common in children with Down syndrome, children who have other autoimmune diseases, children who have a family history of thyroid or autoimmune disease, and children who have a history of radiation treatment for head/neck cancers.
Symptoms of acquired hypothyroidism in children and teenagers
The American Thyroid Association says that two specific symptoms should trigger a strong suspicion of hypothyroidism in children:
First, a slowing of the growth rate for a child’s height. This can also be reflected in shorter-than-average limbs
Second, delayed, later-onset puberty
Other symptoms of acquired hypothyroidism include:
- Enlarged thyroid/goiter
- Full or swollen appearance to neck
- Difficulty swallowing
- Delayed tooth development
- Feeling cold, increased sensitivity to cold
- Dry skin
- Dry, brittle hair
- Hair loss
- Irregular and/or heavy menstrual periods
- Precocious (or early) puberty, including testicular enlargement in boys, and early breast development and/or early menstruation in girls
- Weight gain, even with decreased appetite
- Slow heart rate
- Snoring, sleep apnea
- Milk production from the breasts, known as galactorrhea
- Puffiness and swelling of hands, feet, and face
- Dull facial expression
- Brain fog
- Difficulty concentrating
- Mood or behavior problems
- Difficulties with school performance
How is hypothyroidism diagnosed in infants, children, and teenagers?
Congenital hypothyroidism in newborns is usually diagnosed by the mandatory heel stick blood test that is performed on newborns within 72 hours of birth. Medical errors and oversights still happen, unfortunately, if you are a new parent, you should confirm that the heel stick tests were done on your new baby and review the results for any abnormalities.
In infants, children, and teenagers, hypothyroidism is diagnosed by blood tests for thyroid stimulating hormone (TSH), free thyroxine (Free T4), and free triiodothyronine (Free T3), and in some cases, thyroid peroxidase (TPO) antibodies are tested to diagnose autoimmune Hashimoto’s disease.
What are the reference ranges for infants and children?
The following chart shows reference ranges for TSH, Free T4, and free T3 for six age ranges from birth to 18 years of age.
25th to 75th percentile by age group (in U.S. measurements)
||1 day to 1 month
||1.75 – 5.0
||1.9 – 4.5
||1.75 – 3.5
||1.7 – 3.0
||1.5 – 2.8
||1.3 – 2.35
||1.05 – 1.9
||1.09 – 1.35
||1.1 – 1.4
||1.12 – 1.35
||1.03 – 1.3
||1.05 – 1.3
|Free T3 (female)
||3.5 – 4.75
||3.65 – 4.5
||3.6 – 4.3
||3.6 – 4.3
||3.5 – 4.1
||3.1 – 3.78
|Free T3 (male)
||3.7 – 4.5
||3.7 – 4.4
||3.7 – 4.4
||3.7 – 4.25
||3.7 - 4.2
||3.5 – 4.0
Source: Klaus Kapelari, pediatric reference intervals for thyroid hormone levels from birth to adulthood: a retrospective study
Keep in mind that, as with adult hypothyroidism, some experts feel that the range may be too broad and that it would be more appropriate to offer optimal treatment — treatment that safely resolves symptoms as much as possible, usually targeting narrower reference ranges. If your child’s treatment does not resolve his or her hypothyroidism symptoms, you may want to consult with an integrative or holistic physician to explore a broader range of treatment options.
Treatment for hypothyroidism in infants, children, and teenagers
The conventional treatment for congenital or acquired hypothyroidism in newborns, babies, children, and teenagers is levothyroxine, the synthetic form of thyroxine, the T4 hormone (i.e., Synthroid, Levoxyl, or Tirosint.)
In the past, for hypothyroid newborns and babies, parents were advised to crush the prescribed levothyroxine tablet and mix with formula or breast milk, and administer with a syringe, or have an infant suck it off a parent’s finger. Another option is now available, as Andrea explains:
“Our pediatric endocrinologist is really on top of things, and when my daughter Ava was diagnosed with congenital hypothyroidism, she told me about this liquid levothyroxine drug that had just been approved. I put it in a little syringe, and squirt it in. It’s very easy. Ava is doing great and hitting all her growth targets and developmental milestones at 8 months!”
Andrea is referring to a form of levothyroxine known as Tirosint SOL (levothyroxine oral solution), which was approved by the Food and Drug Administration (FDA) in December of 2016.
If you are the parent of a baby or child with hypothyroidism who is taking a tablet form of levothyroxine, you may want to discuss Tirosint SOL as an option. Liquid medication may be easier to administer — and gets around issues with children who can’t or won’t swallow pills or capsules. There is also evidence that Tirosint-SOL liquid levothyroxine is better able to regulate thyroid levels compared to Tirosint’s levothyroxine liquid gel-caps or regular levothyroxine tablets. According to the manufacturer, IBSA, your baby or child also does not have to wait an hour after taking Tirosint-SOL before eating, a precaution they need to follow with tablet forms of levothyroxine.
For formula-fed infants: There is an important caution regarding the use of levothyroxine — whether tablet or liquid form — in formula-fed infants. According to the FDA, a soy-based formula can impair absorption of levothyroxine and is not recommended in hypothyroid infants.
Advocating for your child
In the article "You Are Your Child’s Best Advocate!" at her ThyroidMom website for parents of children with hypothyroidism, advocate Blythe Clifford shares advice her sister gave her that every parent of a hypothyroid child should take to heart: “Never be afraid to flex that mom muscle!”
There will no-doubt be situations where you must flex that muscle and advocate for your child, by seeking out second or even third opinions from different types of doctors to get a diagnosis or effective treatment.
When Lorena’s oldest daughter was 6 years old, she was diagnosed with a goiter, and a scan found two cysts on her thyroid.
“For two years, I took her to a pediatric endocrinologist who barely examined her, reviewed blood test results, ordered thyroid scans and ultrasounds, and then proceeded to do absolutely nothing to help my daughter get well. She never asked her a single question about how she was feeling — which, by the way, was awful. She dismissed her obvious hypothyroid moon face. By the time she was in second grade, her face was so bloated she looked like a different child. Two years later, the doctor casually mentioned my daughter would probably develop Hashimoto’s thyroiditis, but it was OK. She could take Synthroid and be fine. I asked her if she ever diagnosed hypothyroidism based on symptoms, or only with blood tests. She said she felt confident making a diagnosis based on “blood tests alone.” This was when it dawned on me that this doctor was making me pay to have her watch my child become sicker and do nothing about it … until she developed an autoimmune disease. That was the last time I took her to an endocrinologist. I made an appointment with a holistic doctor who agreed with me that she was hypothyroid. He prescribed natural desiccated thyroid. Within two weeks, you could already see the change in her. I firmly believe that natural thyroid saved my daughter’s life. She is now 19 years old and is still doing well on natural thyroid.
If key hypothyroidism symptoms don’t completely resolve with levothyroxine treatment, pediatric endocrinologist Andrew Bauer, M.D., the medical director of the Pediatric Thyroid Center at Children's Hospital of Philadelphia, has an option:
“It’s worth asking the doctor whether adding a second thyroid hormone, called T3, would be beneficial. We are beginning to see benefits for some adults and children using combined T3 and T4 treatment, although, this approach remains controversial and additional research into this approach is needed.”
Maria Teresa, who was hypothyroid with Hashimoto’s thyroiditis herself, saw the symptoms of hypothyroidism showing up in her teenage daughter Gabriela. Her daughter was finally diagnosed with hypothyroidism and treated with levothyroxine. But when Gabriela continued to struggle in school, gain weight, and feel exhausted on the levothyroxine, Maria Teresa turned to her own integrative doctor, who added the T3 drug Cytomel. Says Maria Teresa:
“I still had symptoms when I was on just levothyroxine. Only when I added the T3 did I start feeling better. It made sense that it could be the same for my daughters. Gabriela’s pediatrician, however, would not even consider it. So, I had her see my more holistic M.D. After she started the natural thyroid, the change was immediate — within days, she had more energy and was so much happier!”
Support for parents
If your child is hypothyroid, don’t go it alone. An excellent source of support for parents is the Magic Foundation — a non-profit organization that provides support to families of children afflicted with a wide variety of chronic and/or critical disorders, syndromes, and diseases that affect a child's growth, including congenital and acquired hypothyroidism. You can learn more about the Magic Foundation’s activities online at their website, www.MagicFoundation.org.
The Magic Foundation also administers two closed parent groups that you can join for support and information. These groups include:
See more helpful articles:
Thyroid Problems in Your Newborn
The Causes of Hypothyroidism
How is Hypothyroidism Treated?