Table of ContentsView AllTable of ContentsSymptomsCausesDiagnosisTreatmentPrognosisCoping
Table of ContentsView All
View All
Table of Contents
Symptoms
Causes
Diagnosis
Treatment
Prognosis
Coping
Triple X syndrome (trisomy X or 47, XXX) is agenetic conditionthat occurs when a female is born with three X chromosomes in all or most of her cells rather than the usual two.Signs and symptoms of triple X syndrome vary widely. Some people may have no signs or symptoms, while others may experience developmental, psychological, and medical symptoms.
This article describes the symptoms associated with triple X syndrome, how it is diagnosed, and the support and treatment options for people with it.
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Triple X Syndrome Symptoms
Signs and symptoms of triple X syndrome vary widely—some people may have no symptoms or may only be mildly affected, while others may have more noticeable symptoms.
Though not everyone with triple X syndrome has apparent physical features associated with the condition, many have some or all of the following:
Many people with triple X syndrome experience a range of developmental, physical, and psychological symptoms, including:
Most people with triple X syndrome experience normal sexual development and fertility. Still, some have abnormal ovarian development (dysgenesis), menstrual irregularities, delayed or early onset puberty, orprimary ovarian failure.
What Causes Triple X Syndrome?
Triple X syndrome is a genetic disorder not usually inherited from a biological parent. It occurs as a random chromosomal error during the formation of reproductive cells (egg and sperm) in one of the parents or early in anembryo’s development.
Typically, people have 46 chromosomes in each of their body’s cells. Two of these chromosomes—X and Y—are sex chromosomes that determine whether a person is born male or female. Females are usually born with XX sex chromosomes, but females born with trisomy X will have an extra copy of the X chromosome in each of their cells.
While most people born with triple X have an extra copy of the X chromosome in all of their body’s cells, some only have an extra X in some of their cells. This is known as 46, XX/47, XXXmosaicism, associated with milder symptoms and fewer developmental and learning delays.
Triple X syndrome cannot be prevented and does not occur due to something a parent did or didn’t do before conception or during pregnancy. Some research suggests women of advanced maternal age (35 or older) are more likely to give birth to a child with triple X syndrome than younger people. However, other studies show that advanced maternal age does not significantly increase the risk.
How Is Triple X Syndrome Diagnosed?
Most babies born with triple X syndrome do not have any obvious physical signs or symptoms at birth. The condition is often undetected until early childhood, when parents express concern to a healthcare provider about their daughter’s developmental or language delays.
If a healthcare provider suspects triple X syndrome, they will take a blood sample and send it to the lab for an analysis of the chromosomes, which can detect extra X chromosomes in the cells.
In recent years, routine prenatal testing has increasingly detected triple X syndrome during pregnancy.Prenatal screening tests, such asnoninvasive prenatal testing (NIPT)orchorionic villus sampling(CVS), can check for genetic disorders like triple X syndrome in fetuses. If NIPT or CVS results indicate that the fetus may have triple X syndrome, anamniocentesis(a procedure to test amniotic fluid) can be performed to confirm the diagnosis.
Sometimes, a triple X syndrome diagnosis may be incidental and given whengenetic testingis performed for a different medical condition.Because it often causes mild symptoms (if any), experts believe that only 10% of people with triple X syndrome get diagnosed.
Treatment for Triple X Syndrome
There is no cure for triple X syndrome, but many treatments and interventions can help manage symptoms and improve quality of life. Treatment for triple X syndrome depends on individual symptoms and the age of diagnosis.
Triple X syndrome treatments can include:
Regular checkups with a healthcare provider are essential for infants and children with triple X syndrome. Along with parents, a healthcare provider can monitor a child’s development for developmental and neuropsychological delays or health problems that may occur.
What Is the Prognosis?
Most people with triple X syndrome lead full, healthy lives. They attend school, have careers, parent children, and live as long as their peers who do not have the disorder.Ongoing medical care and support from healthcare professionals ensure those with the condition get the appropriate care and support for any developmental, physical, or cognitive symptoms.
Coping With Triple X Syndrome
Getting regular checkups to identify and manage any health, behavioral, or developmental issues that may arise is an important part of living with triple X syndrome. If you have a child with triple X syndrome, early intervention services can help address any developmental delays or social and emotional challenges your child experiences.
Summary
Triple X syndrome is a genetic condition that occurs when females are born with three X chromosomes rather than two. While many people with the disorder have no symptoms, it can cause developmental, language, and social delays. Physical characteristics such as flat feet, low muscle tone, wide-spaced eyes, and tall stature are common.
Diagnosis can be made during pregnancy through routine prenatal screening tests or a blood test at any point in a female’s life. Treatment options vary depending on the symptoms but may include early intervention services (e.g., speech therapy, occupational therapy), education support, and counseling. With the proper support, most women and girls with triple X syndrome can live healthy, fulfilling lives.
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