Rett Syndrome in Girls: Insight into the Four Main Stages

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What is Rett Syndrome?

Rett syndrome (also called Rett’s disorder) is a neurodevelopmental disorder that strikes females between the ages of 6 - 18 months. After developing normally for the first several months, children begin to show delays and regression in their gross motor skills. Affected children may become unable to walk, talk or care for themselves independently.

Named after Austrian pediatrician, Andreas Rett, the syndrome was first studied in 1954. In 1999, researchers narrowed the cause of Rett’s down to a random spontaneous mutation of a specific gene on the X chromosome.

Who is Affected?

Unlike other autism spectrum disorders, which have high male to female ratios, Rett syndrome almost exclusively affects girls. 1 in 10,000 to 15,000 girls are affected, regardless of racial or ethnic background. Although similar gene mutations can occur in boys, these babies typically do not survive after birth. Because of the spontaneous nature of the gene mutation, it is very rare for families to have more than one child with Rett’s.

How is Rett’s Syndrome Diagnosed?

A diagnosis of Rett syndrome in girls, is usually made after parents notice that their child is not reaching developmental milestones on time, or has lost previously acquired skills. Family physicians refer to specialists for further physical and neurological evaluations and observations. When Rett syndrome is suspected, genetic testing might be used to confirm a diagnosis.

Progression and severity of Rett syndrome in girls, varies from child to child, though similar characteristics tend to be present. At some point between the ages of 6-18 months, development begins to slow and a child may begin to lose previously developed skills, such as speech and purposeful use of her hands. This regression can be sudden, so when symptoms begin to appear, children may become easily upset and even inconsolable, possibly due to the frustration at being unable to communicate or do the things they used to be able to do.

It is not uncommon for girls to be misdiagnosed with classic autism, as symptoms and behaviors may seem similar early on. One of the biggest differences though, is that children with autism may show preference of objects over people while children with Rett’s seem to prefer people and can be quite affectionate.

What Are the Most Common Symptoms?

A diagnosis of Rett syndrome in girls, can be devastating for a family as children are likely to need continual care and support for the rest of their lives. Four main stages are described, though individuals may show a great deal of variance at each stage.

Early Onset Stage (6-18 Months) – As development begins to slow, infants may fail to acquire expected skills, such as sitting and crawling. Parents might notice less eye contact with family members and reduced interest in toys. Doctors might see reduced growth at check-ups, particularly in head circumference.

Rapid Destructive Stage (Ages 1-4) – Over a period of weeks or months, infants or toddlers may begin to have difficulty crawling or walking, regress in speech and language and start losing the use of their hands. At the same time, they may begin to engage in the wringing or washing hand movements that are characteristic of Rett syndrome.

Plateau or Pseudo-Stationary Stage (Ages 2-10) – In this stage, which can last for years, motor skills continue to decline and seizures may occur frequently. On a positive note, many girls in this stage, will show improved behavior and more interest in people and their environment. Some girls will not progress beyond this stage.

Late Motor Deterioration (Age 10 and beyond) – Here, young women with Rett syndrome might experience further reduced mobility, curvature of spine (scoliosis), muscle weakness, rigidity, and spasticity. Some women in this phase, may see a reduction in compulsive hand movements and increased control of eye gaze.

What Does the Future Hold?

Despite the debilitation caused by Rett syndrome in girls, families report the sweet, good-natured personalities of their children, often noting their ability to communicate love through their eyes.

Many children with Rett syndrome benefit from educational programs and therapies which can increase independence and help individuals learn new skills. Most girls with Rett syndrome will live at least to middle age. Researchers are investigating longer term effects and life expectancy of the disorder and will be able to provide more information in this area in the future.


International Rett Syndrome Foundation: About Rett Syndrome,

National Institute of Neurological Disorders and Stroke: Rett Syndrome Fact Sheet,