Turner Syndrome

What is Turner syndrome?

Turner syndrome (TS) is a congenital condition (present from birth) that only affects females. It happens when one of two of the X chromosomes is missing, either partially or completely.

Turner syndrome leads to a variety of features and symptoms and affects each person differently. But short stature and reduced ovary functioning (primary ovarian insufficiency) are the two most common features.

How common is Turner syndrome?

Turner syndrome affects 1 in 2,000 to 1 in 2,500 female babies. It’s the most common sex chromosome-related condition that affects infant girls.

What causes Turner syndrome?

Humans typically have 23 pairs of chromosomes (46 total). Chromosomes divide into 22 numbered pairs (autosomes) and one pair of sex chromosomes. You receive one chromosome from each biological parent to make a pair.

The 23rd pair normally consists of one X and one Y chromosome for males and two X chromosomes for females. Turner syndrome happens when one of a baby’s two X chromosomes is missing or incomplete. Researchers don’t yet understand why this happens.

Types of Turner syndrome

There are different types of Turner syndrome (TS) based on how one of the X chromosomes is affected:

• Monosomy X: This type means each cell has only one X chromosome instead of two. About 45% of people with TS have monosomy X. The chromosomal abnormality happens randomly during the formation of reproductive cells (eggs or sperm) in the affected person’s biological parent. If one of these atypical reproductive cells contributes to the genetic makeup of a fetus during conception, the baby will have a single X chromosome in each cell at birth.
• Mosaic Turner syndrome: This type makes up about 30% of TS cases. Some of your child’s cells have a pair of X chromosomes, while other cells only have one. It happens randomly during cell division early in pregnancy.
• Inherited Turner syndrome: In rare cases, babies may have inherited TS, meaning their biological parent was born with it and passed it on. This type usually happens because of a missing part of the X chromosome.

What are the symptoms of Turner syndrome?

Turner syndrome presents in many ways. It can cause several different characteristics — or features — as well as certain health conditions, which can vary in severity. Depending on the type of TS, signs of the syndrome may be apparent:

• Before birth.
• Shortly after birth.
• In early childhood.
• In early adolescence.
• In adulthood.

As TS affects everyone differently, you should talk to your healthcare provider about what symptoms and features to expect or look out for based on your or your child’s unique genetic makeup.

Common features of Turner syndrome

The main feature of Turner syndrome is short stature. Almost all people with TS:

• Grow more slowly than their peers during childhood and adolescence. Short stature usually becomes apparent by age 5.
• Have delayed puberty and lack of growth spurts, resulting in an average adult height of 4 feet, 8 inches. (If your child receives a diagnosis early, growth hormone therapy can increase their height by up to 5 inches (average adult height 5’1”).

Another common feature is differences in sexual development. Most people with TS:

• Typically don’t go through puberty unless they get hormone therapy in late childhood and early adolescence.
• May not experience breast development without hormone therapy.
• May not have menstrual periods (amenorrhea).
• Have smaller-than-expected ovaries that may only function for a few years or not at all (primary ovarian insufficiency or POI).
• Have low levels of sex hormones (like estrogen).
• Have infertility.

Besides short stature, people with Turner syndrome often have certain physical traits, which may include:

• Ear differences, including low-set ears, elongated ears, cup-shaped ears and thick ear lobes.
• Low hairline at the back of your neck.
• Small and receding lower jaw, which can affect tooth development and placement.
• A short, wide neck or webbed neck (extra skin folds).
• Broad chest.
• Arms that point out slightly at your elbows (cubitus valgus).
• A missing knuckle in a particular digit (finger or toe), making that digit shorter than the rest.
• Flat feet (pes planus).
• Narrow fingernails and toenails.
• Multiple tiny colored spots (pigmented nevi) on your skin.

Health conditions associated with Turner syndrome

People with Turner syndrome are at an increased risk of also having certain health conditions. But not everyone with TS will develop them.

Cardiovascular conditions

People with Turner syndrome may have heart and blood vessel issues, some of which can be life-threatening. Up to 50% of people with TS are born with a congenital heart condition that affects the structure of their hearts. Cardiovascular problems can include:

• Bicuspid aortic valve.
• Coarctation of the aorta.
• Elongation of the aortic arch.
• High blood pressure (hypertension).

Bone conditions

Bone conditions are also common with TS and may include:

• Increased risk for osteoporosis and bone fractures (breaks), especially if you haven’t received estrogen therapy.
• Scoliosis. This affects about 10% of people with TS.

Autoimmune conditions

TS increases your risk of certain autoimmune conditions, including:

• Celiac disease.
• Hashimoto’s thyroid disease (a type of hypothyroidism).
• Inflammatory bowel disease (IBD).

Hearing and vision issues

Hearing and ear conditions that are common in people with TS include:

• Frequent middle ear infections (otitis media), which may progress to mastoiditis and/or cholesteatoma formation. These are common between the ages of 1 and 6.
• Sensorineural hearing loss. This develops in more than 50% of adults with TS.

The most common vision and eye conditions include:

• Refractive errors (nearsightedness and farsightedness).
• Crossed eyes (strabismus).
• Lazy eye (amblyopia).
• Drooping eyelids (ptosis).

Other, less common issues include red-green color blindness and blue sclera.

Other associated conditions

People with Turner syndrome may also have:

• Kidney conditions: Structural problems in the kidney-urinary system happen in about 30% to 40% of people with TS. This may include horseshoe kidneys or the absence (agenesis) of a kidney. Problems with urine (pee) flow can lead to urinary tract infections (UTIs).
• Metabolic syndrome: People with TS are at an increased risk for metabolic syndrome — a group of conditions that increase your risk of developing cardiovascular disease, Type 2 diabetes and stroke.
• Lymphedema: This condition can cause swollen, puffy hands and feet.
• Learning disabilities: People with Turner syndrome often have typical intelligence levels but a higher risk of developing learning disabilities. This usually involves issues with visual-motor and visual-spatial skills. It can be difficult to see how objects relate to each other in space. For example, driving may be difficult.
• Mental health challenges: Living with Turner syndrome may lead to issues with self-esteem and/or chronic stress, which can cause anxiety and/or depression.

How is Turner syndrome diagnosed?

Healthcare providers may diagnose Turner syndrome at any stage of a child’s development after birth. Sometimes, they can detect the condition before birth with the following tests:

• Noninvasive prenatal testing (NIPT): This is a screening blood test for the pregnant woman. It checks for signs that show an increased chance of a chromosomal issue with the fetus.
• Ultrasound during pregnancy: An ultrasound may show that the fetus has some physical features of TS, like heart problems or fluid around the neck. They’ll likely request amniocentesis or chorionic villus sampling to help confirm the diagnosis.
• Amniocentesis and chorionic villus sampling: These tests check the amniotic fluid or tissue from the placenta. Providers perform a genetic test with karyotype analysis on the fluid or tissue, which can confirm if the fetus has Turner syndrome.

Other times, children receive a diagnosis soon after birth or during early childhood because of their symptoms. But some people aren’t diagnosed with Turner syndrome until they reach adulthood. These people may go through puberty and get their periods. But they often have primary ovarian insufficiency (early menopause).

After birth, a genetic test with karyotype analysis is the test that confirms a Turner syndrome diagnosis. This test requires a blood draw.

What is the treatment for Turner syndrome?

There’s no cure for Turner syndrome. But certain medications and therapies can help manage its symptoms.

Besides care for related medical problems (like heart conditions), Turner syndrome treatment often focuses on hormones. Treatments may include:

• Human growth hormone therapy: Injections of human growth hormone help with vertical growth. If treatment starts early enough, these shots can increase your child’s final height by several inches.
• Estrogen therapy: Often, people with TS have low levels of estrogen, a sex hormone, which impacts their sexual development. Estrogen can help with breast development and menstruation. Estrogen replacement improves brain development, heart function, liver function and bone health, too.
• Cyclic progestins: These medications induce regular menstrual periods. Healthcare providers typically start them around the age of 11 or 12.

Who should be on my child’s care team for Turner syndrome?

Treatment for Turner syndrome depends on each child’s specific symptoms and development. A coordinated care team can provide the most comprehensive, effective care. The team will look at the whole picture and tailor a plan that works for your child.

Usually, children with Turner syndrome primarily see their pediatricians. They also receive evaluation and monitoring from pediatric endocrinologists. These hormone specialists can provide recommendations on how to treat hormone deficiencies.

Other pediatric specialists may include:

• Cardiologists.
• Ophthalmologists.
• Otolaryngologists (ENTs).
• Nephrologists.
• Psychologists.

Parents can help the care team by keeping growth charts and tracking other symptoms. It’s also a good idea for families to get genetic counseling.

Can Turner syndrome be prevented?

There’s nothing you can do to prevent Turner syndrome. It happens randomly at conception. Biological parents can’t do anything to stop it from happening and it’s not their fault.

What can I expect if my child has Turner syndrome?

It’s important to remember that no two people with Turner syndrome are affected in the same way. It’s impossible to predict how it’ll affect your child. The best way you can prepare is to talk to healthcare providers who specialize in Turner syndrome.

What is the life expectancy of someone with Turner syndrome?

The life expectancy for people with Turner syndrome might be slightly shorter. But by testing for and treating the health conditions that can come with TS, people with TS can expect to have a typical lifespan.

How can I take care of my child with Turner syndrome?

Early diagnosis is key. Pay attention to your child’s growth and milestones. Perhaps you noticed your child doesn’t seem to be growing as you expect, or you see unusual physical symptoms. Talk to their pediatrician about any concerns.

Certain treatments, such as hormone therapy, are most effective if you start them early. It’s also important to stay on top of other medical concerns, such as heart problems. Your child will likely need regular monitoring and checkups to keep tabs on their health and any concerns.

Providers also recommend that children with Turner syndrome:

• Get screened for learning disabilities: This should happen as early as 1 or 2 years of age. Working with your child’s teachers can help address issues before learning disabilities get more serious.
• Work with a mental health professional: A therapist, like a child psychologist, can help with social issues and low self-esteem, anxiety and depression. Cognitive-behavioral therapy (CBT), a type of psychotherapy (talk therapy), can help your child navigate and cope with these challenges.

What questions should I ask my doctor?

If your child has Turner syndrome, ask your provider:

• What are the treatment options?
• What are the risks and benefits of growth hormone injections and other hormone treatments?
• When should hormone treatments begin?
• What other medical conditions is my child at risk for?
• What specialists should be on their care team?
• What type of learning disabilities may occur?
• What kind of resources are available to help me care for my child’s specific needs?