Triple X syndrome, also known as Trisomy X, 47,XXX aneuploidy, and Triplo-X, XXX Syndrome is a chromosomal abnormality that affects approximately 1 in every 1,000 females. A healthy female has two X chromosomes, one from her father and one from her mother. A female with triple-X syndrome has three X chromosomes.

According to the NIH (National Institutes of Health), USA, 5 to 10 girls with triple X syndrome are born in the USA each day.

A female with triple-X syndrome does not inherit it from her parents. The syndrome generally results from a mistake in the formation of the father’s sperm cell or the mother’s egg. In some cases triple-X syndrome may be the result of something that went wrong in the development of the embryo.

A girl with triple X syndrome may either have no symptoms, just mild ones, or more severe ones with developmental delays. Developmental delays may include learning disabilities, delayed development of speech and language skills, as well as motor skills. There may be behavioral and emotional difficulties. Approximately 10% of affected females have seizures or kidney abnormalities. Among those who do have symptoms, they will vary widely from person-to-person.

Triple X syndrome treatment varies and depends on which symptoms are present, and how severe they are.

Unlike the majority of other chromosomal conditions, there is usually no clear visual difference between a female with triple X syndrome and other females. Some females with triple X syndrome may be taller than average. Most individuals with the syndrome have normal sexual development and can conceive children. Infertility is possible in some cases, but it is rare.

Most medical professionals do not regard the condition as a disability.

What are the signs and symptoms of triple X syndrome?
A symptom is something the patient senses and describes, while a sign is something other people, such as the doctor notice. For example, drowsiness may be a symptom while dilated pupils may be a sign.

In all female cells, only one X chromosome is active at any time. Consequently, triple X syndrome generally does not cause unusual physical features or medical problems. In other words, in the majority of cases there are no signs or symptoms. If symptoms do occur, they may include:

• Delayed language skill development
• Delayed motor skill development, resulting in poor coordination, awkwardness, and/or clumsiness.
• In very rare cases, infertility
• Some may have menstrual irregularities
• Some may experience an early onset of menstruation

If physical features are present they will be very mild:

• Tall stature
• Microcephaly (small head)
• Epicanthal folds – a vertical fold of skin that comes down across the inner angle of the eye.
• Increased width between the eyes