Stages of Rett syndrome

Rett syndrome is a neurological disorder that affects brain development,   leading to severe mental and physical problems.

The disease, which affects girls almost exclusively, progresses in four stages:

Stage 1 (early onset phase)

During this phase, children’s growth begins to lag behind others. This usually starts between ages 6 to 18 months when the first symptoms are recognized. This phase can last for up to one year. In some instances, the symptoms may be very subtle at first and may go unnoticed. The main symptoms of stage 1 are :

  • Issues with sitting, crawling, and walking
  • Lack of interest in toys
  • Abnormal hand movements
  • Problems in speech development
  • Low muscle tone, or hypotonia

Stage 2 (rapid destructive phase)

This usually is observed between ages 1 and 4. The duration of this phase can be anywhere between two months and two years. The main signs of stage 2 are:

  • Loss of previously acquired motor, communication, and social skills
  • Loss of the ability to use hands purposefully. Instead, patients show abnormal hand movements such as clasping or squeezing, clapping or tapping, and hand-washing movements
  • Speech defects
  • Irritability characterized by children screaming or crying without reason
  • Mobility and coordination problems including unsteady gait
  • Reduced head circumference (acquired microcephaly)
  • Emergence of breathing issues such as rapid breathing and breath holding

Stage 3 (plateau phase)

This phase usually begins between ages, 2 and 10 and can last for many years. During this phase, there may be improvements in hand usage, alertness, communication skills, walking ability, and irritability (less crying). The main symptoms of stage 3 are:

  • Seizures
  • Worsening of breathing problems
  • Development of cardiac arrhythmias (abnormal heart rhythm) in some children
  • Teeth grinding
  • Difficulty to gain and maintain weight

Stage 4 (late motor deterioration phase)

This usually begins at about age 10 and can last for years or decades. During this stage, breathing problems, seizures, and abnormal hand movements may become less common. Also, communication skills and understanding may remain stable or improve slightly. The main symptoms during this phase are:

  • Reduced mobility, muscle weakness and stiffness, and stiffness in joints
  • Scoliosis (abnormal curvature of the spine)
  • Loss of walking ability


Rett Syndrome News Today is strictly a news and information website about the disease. It does not provide medical advice, diagnosis or treatment. This content is not intended to be a substitute for professional medical advice, diagnosis, or treatment. Always seek the advice of your physician or another qualified health provider with any questions you may have regarding a medical condition. Never disregard professional medical advice or delay in seeking it because of something you have read on this website.