{"h1":"What is Rett Syndrome, and what does it look like in early childhood?","faq":[{"a":"It is seen overwhelmingly in girls, because it is usually linked to a change in the MECP2 gene on the X chromosome. It can occur in boys but is far rarer and often presents differently. A clinician and genetic testing confirm the picture.","q":"Does Rett Syndrome only affect girls?"},{"a":"A period of typical early development followed by loss of skills, especially purposeful hand use and language, is a recognised pattern. Many conditions can cause regression, so any loss of previously gained skills should be assessed promptly by a paediatrician or paediatric neurologist.","q":"My baby developed normally and then started losing skills — could it be Rett Syndrome?"},{"a":"Yes. While Rett Syndrome itself is genetic, occupational, physical and communication therapies help protect movement, support hand function, build alternative communication and improve everyday participation. Support is most effective when started early.","q":"Can therapy help a child with Rett Syndrome?"}],"lang":"en","slug":"what-is-rett-syndrome-and-what-does-it-look-like-in-early-childhood","title":"What is Rett Syndrome, and what does it look like in early childhood?","entity":{"key":"rett","kind":"condition","name":"Rett Syndrome","slug":"rett-syndrome"},"lenses":[{"kind":"stakeholder","label":"Parent","value":"parent"},{"kind":"domain","label":"Context","value":"context"},{"kind":"intent","label":"Definition","value":"definition"},{"kind":"lifecycle","label":"Act","value":"act"},{"kind":"route","label":"Screen","value":"screen"},{"kind":"empowerment","label":"Early Clarity","value":"early_clarity"}],"parent":{"key":"conditions","label":"Conditions"},"related":[{"lang":"en","slug":"how-does-rett-syndrome-affect-a-child-s-motor-development","title":"How Rett Syndrome Affects Motor Development"},{"lang":"en","slug":"how-common-is-rett-syndrome-in-children","title":"How Common Is Rett Syndrome in Children?"},{"lang":"en","slug":"how-is-rett-syndrome-diagnosed-in-a-child","title":"How is Rett Syndrome diagnosed in a child?"},{"lang":"en","slug":"what-is-rett-syndrome","title":"What is Rett Syndrome?"},{"lang":"en","slug":"what-are-the-early-signs-of-rett-syndrome","title":"Early Signs of Rett Syndrome"},{"lang":"en","slug":"what-are-the-early-signs-of-rett-syndrome-in-a-6-year-old","title":"Early Signs of Rett Syndrome in a 6-Year-Old"}],"summary":"Rett Syndrome (ICD-11 LD90.0) is a rare neurodevelopmental condition affecting mostly girls, usually caused by a MECP2 gene change. After typically normal early development, skills slow and are lost — especially purposeful hand use and spoken language, with characteristic repetitive hand movements. Diagnosis is clinical and genetic, formed only at a Pinnacle centre.","answer_md":"*When a baby girl develops beautifully for a few months and then her hands seem to lose their purpose, that change has a name — and an explanation.*\n\n## In short\nRett Syndrome is a rare neurodevelopmental condition, recognised under ICD-11 as **LD90.0**, that affects mostly girls and is usually caused by a change in the *MECP2* gene. Its hallmark is a period of early development that appears typical, followed by a slowing and then a loss of skills already gained — particularly purposeful use of the hands and spoken language. It is identified by clinicians, not by parents, and early recognition opens the door to supportive therapy and genetic confirmation.\n\n## What it can look like in early childhood\nMost babies with Rett Syndrome grow and develop as expected for the first 6–18 months. Then a recognisable pattern may emerge:\n\n- A **slowing of head growth** in the first two years\n- **Loss of purposeful hand skills** that were already there — reaching, grasping, holding\n- **Repetitive hand movements** such as wringing, washing, clapping or mouthing\n- **Loss of spoken words or babble** and reduced social engagement, which may later partly return\n- **Walking that becomes unsteady**, or difficulty starting to walk\n- Changes in breathing patterns when awake, and reduced eye-pointing or gaze communication\n\nBecause this involves a *loss* of previously gained skills, any regression at any age deserves prompt medical attention — not a wait-and-watch approach.\n\n## The Pinnacle way\nDevelopmental measurement supports care planning; diagnosis requires an appropriately qualified healthcare professional., under qualified clinician care — genetic testing and paediatric neurology confirm Rett Syndrome itself. From there, your child's [strengths and support needs are mapped](/ask/what-is-the-abilityscore-and-how-is-it-calculated), and [occupational therapy](https://www.pinnacleblooms.org/best-occupational-therapy-center-india-proven-improvement-rate) helps protect and rebuild everyday hand and self-care skills. Learn more about [Rett Syndrome](/rett-syndrome) and how families are supported.\n\n## Trusted sources\nWHO ICD-11 classification of Rett Syndrome; American Academy of Pediatrics guidance on developmental regression; ICF framework for functioning and support.\n\n**Next step —** If your child has lost skills she once had, [speak with a Pinnacle clinician](https://www.pinnacleblooms.org/best-occupational-therapy-center-india-proven-improvement-rate) without delay.\n\nThis is general information, not a diagnosis — individual assessment and diagnosis require an appropriately qualified healthcare professional.","canonical":"https://pinnacleblooms.org/ask/what-is-rett-syndrome-and-what-does-it-look-like-in-early-childhood","editorial":{"reviewed_at":"2026-06-11T20:12:18.613642+00:00","reviewed_by":null,"developed_by":"SETU Consortium · Pinnacle Blooms Network"},"alternates":[{"href":"https://pinnacleblooms.org/ask/what-is-rett-syndrome-and-what-does-it-look-like-in-early-childhood","lang":"en","indexable":true}],"dimensions":[{"key":"conditions","label":"Conditions"}],"meta_title":"Rett Syndrome: Early Signs Explained","meta_robots":"index, follow, max-image-preview:large","everyday_tip":"Keep a simple month-by-month note or short videos of your child's milestones. A clear picture of what skills appeared — and any that faded — is one of the most helpful things you can bring to a clinician.","published_at":"2026-06-10T10:28:00.07239+00:00","reading_paths":[{"key":"understand","items":[{"lang":"en","slug":"what-is-rett-syndrome","title":"What is Rett Syndrome?","reason":"Linked from this answer"},{"lang":"en","slug":"how-does-rett-syndrome-affect-a-child-s-daily-life","title":"How Rett Syndrome Affects a Child's Daily Life","reason":"Same topic"},{"lang":"en","slug":"is-rett-syndrome-considered-a-disability","title":"Is Rett Syndrome considered a disability?","reason":"Same topic"},{"lang":"en","slug":"is-rett-syndrome-genetic-or-hereditary","title":"Is Rett Syndrome Genetic or Hereditary?","reason":"Same topic"},{"lang":"en","slug":"what-are-common-myths-about-rett-syndrome","title":"What are common myths about Rett Syndrome?","reason":"Same topic"},{"lang":"en","slug":"what-are-the-types-or-levels-of-rett-syndrome","title":"Types and Stages of Rett Syndrome","reason":"Same topic"},{"lang":"en","slug":"what-causes-rett-syndrome-in-children","title":"What causes Rett syndrome in children?","reason":"Same topic"},{"lang":"en","slug":"what-other-conditions-often-occur-alongside-rett-syndrome","title":"Conditions That Occur Alongside Rett Syndrome","reason":"Same topic"},{"lang":"en","slug":"what-does-current-research-show-about-early-intervention-outcomes-for-rett-syndrome-in-children-under-7","title":"Early Intervention Outcomes in Rett Syndrome (Under 7)","reason":"Same topic"},{"lang":"en","slug":"what-is-rett-syndrome-and-what-are-its-icd-11-features-in-early-childhood","title":"What is Rett Syndrome, and its ICD-11 features in early childhood?","reason":"Same topic"},{"lang":"en","slug":"what-is-the-icd-11-classification-for-rett-syndrome","title":"ICD-11 Classification of Rett Syndrome (LD90.0)","reason":"Same topic"},{"lang":"en","slug":"what-is-the-snomed-ct-concept-for-rett-syndrome","title":"What is the SNOMED CT concept for Rett Syndrome?","reason":"Same topic"}],"label":"Understand the subject","total":13},{"key":"signs","items":[{"lang":"en","slug":"what-are-the-early-signs-of-rett-syndrome","title":"Early Signs of Rett Syndrome","reason":"Linked from this answer"},{"lang":"en","slug":"what-are-the-early-signs-of-rett-syndrome-in-a-6-year-old","title":"Early Signs of Rett Syndrome in a 6-Year-Old","reason":"Linked from this answer"},{"lang":"en","slug":"can-rett-syndrome-be-cured","title":"Can Rett Syndrome Be Cured?","reason":"Same topic"},{"lang":"en","slug":"can-rett-syndrome-be-prevented","title":"Can Rett Syndrome Be Prevented?","reason":"Same topic"},{"lang":"en","slug":"do-boys-show-rett-syndrome-differently","title":"Rett Syndrome in Boys","reason":"Same topic"},{"lang":"en","slug":"do-girls-show-rett-syndrome-differently","title":"Do girls show Rett Syndrome differently?","reason":"Same topic"},{"lang":"en","slug":"should-i-be-worried-my-child-might-have-rett-syndrome","title":"Should I be worried my child might have Rett Syndrome?","reason":"Same topic"},{"lang":"en","slug":"what-are-the-early-signs-of-rett-syndrome-in-a-1-year-old-boy","title":"Early signs of Rett syndrome in a 1-year-old boy","reason":"Same topic"},{"lang":"en","slug":"what-are-the-early-signs-of-rett-syndrome-in-a-1-year-old-girl","title":"Early Signs of Rett Syndrome in a 1-Year-Old Girl","reason":"Same topic"},{"lang":"en","slug":"what-are-the-early-signs-of-rett-syndrome-in-a-12-to-18-month-old","title":"Early Signs of Rett Syndrome at 12–18 Months","reason":"Same topic"},{"lang":"en","slug":"what-are-the-early-signs-of-rett-syndrome-in-a-18-to-24-month-old","title":"Early Signs of Rett Syndrome in an 18-to-24-Month-Old","reason":"Same topic"},{"lang":"en","slug":"what-are-the-early-signs-of-rett-syndrome-in-a-2-year-old","title":"Early Signs of Rett Syndrome in a 2-Year-Old","reason":"Same topic"}],"label":"Recognise signs & concerns","total":47},{"key":"causes","items":[{"lang":"en","slug":"how-does-rett-syndrome-affect-a-child-s-motor-development","title":"How Rett Syndrome Affects Motor Development","reason":"Linked from this answer"},{"lang":"en","slug":"are-boys-more-likely-to-have-rett-syndrome","title":"Are boys more likely to have Rett Syndrome?","reason":"Same topic"},{"lang":"en","slug":"are-girls-more-likely-to-have-rett-syndrome","title":"Are girls more likely to have Rett Syndrome?","reason":"Same topic"},{"lang":"en","slug":"what-causes-rett-syndrome-in-young-children","title":"What Causes Rett Syndrome in Young Children?","reason":"Same topic"},{"lang":"en","slug":"how-does-early-intervention-for-rett-syndrome-advance-un-child-rights-uncrpd-and-the-sdgs","title":"Early Intervention for Rett Syndrome, UNCRPD & the SDGs","reason":"Same topic"},{"lang":"en","slug":"what-are-the-known-contributing-factors-for-rett-syndrome-in-early-childhood","title":"Known contributing factors for Rett Syndrome","reason":"Same topic"},{"lang":"en","slug":"what-is-the-cost-effectiveness-of-early-therapy-for-rett-syndrome-in-young-children","title":"Cost-effectiveness of early therapy for Rett Syndrome in young children","reason":"Same topic"},{"lang":"en","slug":"what-is-the-prevalence-and-public-health-burden-of-rett-syndrome-among-young-children-in-india","title":"Prevalence and Public-Health Burden of Rett Syndrome in India","reason":"Same topic"}],"label":"Explore causes & influences","total":8},{"key":"assess","items":[{"lang":"en","slug":"how-does-abilityscore-track-progress-in-a-child-with-rett-syndrome","title":"How AbilityScore Tracks Progress in a Child with Rett Syndrome","reason":"Same topic"},{"lang":"en","slug":"how-is-rett-syndrome-assessed-in-a-young-child","title":"How Rett Syndrome Is Assessed in a Young Child","reason":"Same topic"},{"lang":"en","slug":"how-is-rett-syndrome-assessed-in-children-under-7","title":"How Rett Syndrome Is Assessed in Children Under 7","reason":"Same topic"},{"lang":"en","slug":"what-does-an-abilityscore-of-0-100-mean-for-a-child-with-rett-syndrome","title":"What an AbilityScore® of 0–100 means for a child with Rett Syndrome","reason":"Same topic"},{"lang":"en","slug":"what-does-an-abilityscore-of-100-200-mean-for-a-child-with-rett-syndrome","title":"What does an AbilityScore of 100–200 mean for a child with Rett Syndrome?","reason":"Same topic"},{"lang":"en","slug":"what-does-an-abilityscore-of-200-300-mean-for-a-child-with-rett-syndrome","title":"What does an AbilityScore of 200–300 mean for a child with Rett Syndrome?","reason":"Same topic"},{"lang":"en","slug":"what-does-an-abilityscore-of-300-400-mean-for-a-child-with-rett-syndrome","title":"AbilityScore 300–400 in Rett Syndrome","reason":"Same topic"},{"lang":"en","slug":"what-does-an-abilityscore-of-400-500-mean-for-a-child-with-rett-syndrome","title":"What an AbilityScore of 400–500 Means in Rett Syndrome","reason":"Same topic"},{"lang":"en","slug":"what-does-an-abilityscore-of-500-600-mean-for-a-child-with-rett-syndrome","title":"What does an AbilityScore of 500–600 mean for a child with Rett Syndrome?","reason":"Same topic"},{"lang":"en","slug":"what-does-an-abilityscore-of-600-700-mean-for-a-child-with-rett-syndrome","title":"What does an AbilityScore of 600–700 mean for a child with Rett Syndrome?","reason":"Same topic"},{"lang":"en","slug":"what-does-an-abilityscore-of-700-800-mean-for-a-child-with-rett-syndrome","title":"What an AbilityScore of 700–800 Means for a Child with Rett Syndrome","reason":"Same topic"},{"lang":"en","slug":"what-does-an-abilityscore-of-800-900-mean-for-a-child-with-rett-syndrome","title":"What an AbilityScore of 800–900 Means for a Child with Rett Syndrome","reason":"Same topic"}],"label":"Understand assessment","total":16},{"key":"therapy","items":[{"lang":"en","slug":"how-is-rett-syndrome-diagnosed-in-a-child","title":"How is Rett Syndrome diagnosed in a child?","reason":"Linked from this answer"},{"lang":"en","slug":"how-common-is-rett-syndrome-in-children","title":"How Common Is Rett Syndrome in Children?","reason":"Linked from this answer"},{"lang":"en","slug":"can-a-child-with-rett-syndrome-attend-a-mainstream-school","title":"Can a Child with Rett Syndrome Attend a Mainstream School?","reason":"Same topic"},{"lang":"en","slug":"can-a-child-with-rett-syndrome-attend-a-regular-school","title":"Can a Child with Rett Syndrome Attend a Regular School?","reason":"Same topic"},{"lang":"en","slug":"can-a-child-with-rett-syndrome-grow-up-to-live-independently","title":"Can a Child with Rett Syndrome Live Independently?","reason":"Same topic"},{"lang":"en","slug":"how-is-rett-syndrome-supported-through-therapy","title":"How is Rett Syndrome supported through therapy?","reason":"Same topic"},{"lang":"en","slug":"my-child-with-rett-syndrome-has-an-abilityscore-of-0-100-what-should-we-do-next","title":"Rett Syndrome AbilityScore®: What to Do Next","reason":"Same topic"},{"lang":"en","slug":"my-child-with-rett-syndrome-has-an-abilityscore-of-100-200-what-should-we-do-next","title":"Rett Syndrome with an AbilityScore of 100–200: your next step","reason":"Same topic"},{"lang":"en","slug":"my-child-with-rett-syndrome-has-an-abilityscore-of-200-300-what-should-we-do-next","title":"Rett Syndrome: AbilityScore 200–300 — what to do next","reason":"Same topic"},{"lang":"en","slug":"my-child-with-rett-syndrome-has-an-abilityscore-of-300-400-what-should-we-do-next","title":"Rett Syndrome: AbilityScore 300–400 — what to do next","reason":"Same topic"},{"lang":"en","slug":"my-child-with-rett-syndrome-has-an-abilityscore-of-400-500-what-should-we-do-next","title":"Rett Syndrome with an AbilityScore of 400–500: what to do next","reason":"Same topic"},{"lang":"en","slug":"my-child-with-rett-syndrome-has-an-abilityscore-of-500-600-what-should-we-do-next","title":"Rett Syndrome and an AbilityScore of 500–600: What To Do Next","reason":"Same topic"}],"label":"Explore therapy & support","total":68},{"key":"home","items":[{"lang":"en","slug":"how-can-i-support-my-child-with-rett-syndrome-at-home","title":"How can I support my child with Rett Syndrome at home?","reason":"Same topic"}],"label":"At home & in everyday life","total":1}],"what_to_watch":"Watch for loss of skills your child once had — especially purposeful hand use, babble or words — together with repetitive hand wringing or washing movements and slowing head growth. Any regression deserves prompt medical attention.","authority_links":[{"url":"https://icd.who.int/","code":"LD90.0","label":"WHO ICD-11: Rett Syndrome (LD90.0)"},{"url":"https://www.healthychildren.org/","label":"AAP HealthyChildren: developmental concerns and regression"},{"url":"https://www.who.int/","label":"WHO ICF framework for functioning and support"}],"last_reviewed_at":"2026-06-10T10:28:00.07239+00:00","meta_description":"Rett Syndrome is a rare neurodevelopmental condition affecting mostly girls. Learn what it is and how it can appear in early childhood — warmly explained.","related_materials":[],"related_techniques":[]}