The symptoms of Rett Syndrome

The symptoms of Rett Syndrome can appear quickly or take months to develop. It is not always obvious to begin with. A child with Rett Syndrome may not have every symptom listed below, and their symptoms can change as they get older.

Early signs

In the first six months, a child with Rett Syndrome will usually develop and grow normally although later, subtle signs of Rett Syndrome may be recognized in hindsight. Early signs usually appear within the first 6-18 months, including:

  • Low muscle tone (hypotonia)
  • Difficulty feeding
  • Unusual, repetitive hand movements or jerky limb movements
  • Delay with development of speech
  • Mobility problems, such as problems sitting, crawling and walking
  • Lack of interest in toys

Signs of regression

Between the ages of one and four, a child with Rett Syndrome will lose some of their abilities. The child will gradually or suddenly start to develop severe problems with communication and language, memory, hand use, mobility, coordination and other brain functions. Symptoms include:

  • Loss of purposeful hand use
  • Repetitive hand movements, including wringing, washing, clapping or tapping
  • Periods of distress, irritability, agitation, screaming for no obvious reason
  • Loss of interest in people and avoiding eye contact
  • Unsteady or awkward walking pattern
  • Difficulty sleeping
  • Difficulty chewing and swallowing typical size/texture food for their age
  • Constipation, causing stomach aches and distress
  • Slowing of head growth compared to typical peers

Later signs

Later on, a child may experience periods of rapid breathing (hyperventilation) or slow breathing, including breath-holding. They may also swallow air which can lead to abdominal bloating.

Rett Syndrome in boys

Although rare, boys can also have Rett Syndrome. There are several specific genetic scenarios that can happen which you can read more about on the Rett Syndrome Research Trust website. The good news is that almost all the research we support is applicable to boys as well as girls.


More information about Rett Syndrome in boys

Diagnosis questions

A Rett Syndrome diagnosis is devastating but you are not alone. Fellow parents have identified some key questions they had before, during, and after their child’s diagnosis.


Download diagnosis questions PDF (4 pages)

Living with Rett Syndrome

Practical information and resources to help keep children and adults with Rett Syndrome healthy until treatments and a cure become available.