# Early Signs of Rett Syndrome in a 9-to-12-Month-Old

Canonical: https://pinnacleblooms.org/ask/what-are-the-early-signs-of-rett-syndrome-in-a-9-to-12-month-old
Publisher: Pinnacle Blooms Network / Bharath Healthcare Laboratories Private Limited

In a 9-to-12-month-old, early signs of Rett Syndrome are often subtle: a slowing or plateau in development, less use of the hands for reaching and grasping, low muscle tone, and slower head growth. The key signal is loss or stalling of previously gained skills, which always warrants a prompt paediatric check. Rett Syndrome is rare and confirmed by clinical assessment and genetic testing, not at home.

*Your baby met her early milestones beautifully — so what does it mean if, somewhere around the first birthday, the pace seems to gently shift?*

## In short
Rett Syndrome is rare, and in the 9-to-12-month window the signs are often subtle. Many babies develop typically at first, then show a slowing or plateau in their progress — a quieter use of the hands, less reaching and grasping, lower muscle tone (a 'floppy' feel), and slower head growth. These are gentle signals to *observe and discuss with a doctor*, never to diagnose at home, because Rett Syndrome is confirmed through clinical assessment and genetic testing. If you notice a loss of skills your baby once had, that always deserves a prompt paediatric check.

## Early signs to watch (9–12 months)
**Movement and hands**
- Hands used less for reaching, grasping or exploring toys than before
- Early hints of repetitive hand movements (wringing, mouthing or hand-to-hand actions)
- A 'floppy' or low-tone feel; less push against gravity in sitting or rolling

**Growth and head**
- Head circumference growth slowing across health-check visits (deceleration), even though birth head size was normal

**Development and engagement**
- A plateau — skills that were emerging stop progressing as expected
- Reduced babbling, eye engagement or social back-and-forth at times
- Less interest in crawling or weight-bearing on the legs

What matters most is **loss or stalling of skills your baby previously had** — regression is the signal that always warrants a prompt medical review, rather than waiting.

## When to seek a check
Rett Syndrome is uncommon and usually becomes clearer between 12 and 24 months, so at 9–12 months these are early observations, not conclusions. Because it can involve loss of acquired skills and is confirmed by genetic testing (most often an MECP2 gene change), this is a **see-your-paediatrician** situation, not a therapy-first one. Bring your child for a developmental and paediatric review if you notice any loss of hand use, slowing head growth, or skills that have stopped progressing. Early medical clarity opens the door to the right support and to families who understand the journey.

## The Pinnacle way
At [Pinnacle Blooms Network](/), we begin with what your child *can* do and what helps her thrive — working alongside your medical team, never instead of them. Strengths-first [occupational therapy](https://www.pinnacleblooms.org/best-occupational-therapy-center-india-proven-improvement-rate) supports hand use, posture and everyday play, with parents coached as everyday partners. A clinical [AbilityScore®](/ask/what-is-the-abilityscore-and-how-is-it-calculated) and any diagnosis are formed only at a Pinnacle Blooms Network centre under qualified clinician care — nothing here is a diagnosis. You can learn more about [Rett Syndrome](/rett-syndrome) and how gentle, child-led support works. Across 70+ centres in 4 states and 4.95 lakh+ families served, our aim is steady, dignified progress.

## Trusted sources
Aligned with WHO ICD-11 (LD90.0 Rett syndrome), American Academy of Pediatrics and HealthyChildren.org guidance on developmental surveillance and head-growth monitoring, and CDC resources on developmental milestones and acting early when skills are lost.

**Next step —** if you've noticed any slowing or loss of skills, please see your paediatrician promptly, and reach our clinical team on WhatsApp at +91 91001 81181 so we can understand your child together.

This is general information, not a diagnosis — individual assessment and diagnosis require an appropriately qualified healthcare professional.

## Sources
- WHO ICD-11: Rett syndrome: https://icd.who.int/
- HealthyChildren.org — developmental milestones and acting early: https://www.healthychildren.org/
- CDC — Learn the Signs. Act Early.: https://www.cdc.gov/child-development

## Connected topics and perspectives
- Conditions: https://pinnacleblooms.org/ask/conditions
- Parent: https://pinnacleblooms.org/ask/lens/stakeholder/parent
- Infant-9-12: https://pinnacleblooms.org/ask/lens/age/infant-9-12
- Context: https://pinnacleblooms.org/ask/lens/domain/context
- Early Signs: https://pinnacleblooms.org/ask/lens/intent/early_signs
- Screen: https://pinnacleblooms.org/ask/lens/lifecycle/screen
- Special Education: https://pinnacleblooms.org/ask/lens/route/special-education
- Early Clarity: https://pinnacleblooms.org/ask/lens/empowerment/early_clarity

## Related question paths

### Understand the subject
- How Rett Syndrome Affects a Child's Daily Life: https://pinnacleblooms.org/ask/how-does-rett-syndrome-affect-a-child-s-daily-life
- Is Rett Syndrome considered a disability?: https://pinnacleblooms.org/ask/is-rett-syndrome-considered-a-disability
- Is Rett Syndrome Genetic or Hereditary?: https://pinnacleblooms.org/ask/is-rett-syndrome-genetic-or-hereditary
- What are common myths about Rett Syndrome?: https://pinnacleblooms.org/ask/what-are-common-myths-about-rett-syndrome
- Types and Stages of Rett Syndrome: https://pinnacleblooms.org/ask/what-are-the-types-or-levels-of-rett-syndrome
- What causes Rett syndrome in children?: https://pinnacleblooms.org/ask/what-causes-rett-syndrome-in-children
- What is Rett Syndrome?: https://pinnacleblooms.org/ask/what-is-rett-syndrome
- What is Rett Syndrome, and what does it look like in early childhood?: https://pinnacleblooms.org/ask/what-is-rett-syndrome-and-what-does-it-look-like-in-early-childhood
- Conditions That Occur Alongside Rett Syndrome: https://pinnacleblooms.org/ask/what-other-conditions-often-occur-alongside-rett-syndrome
- Early Intervention Outcomes in Rett Syndrome (Under 7): https://pinnacleblooms.org/ask/what-does-current-research-show-about-early-intervention-outcomes-for-rett-syndrome-in-children-under-7
- What is Rett Syndrome, and its ICD-11 features in early childhood?: https://pinnacleblooms.org/ask/what-is-rett-syndrome-and-what-are-its-icd-11-features-in-early-childhood
- ICD-11 Classification of Rett Syndrome (LD90.0): https://pinnacleblooms.org/ask/what-is-the-icd-11-classification-for-rett-syndrome

### Recognise signs & concerns
- Early Signs of Rett Syndrome in a 6–9-Month-Old: https://pinnacleblooms.org/ask/what-are-the-early-signs-of-rett-syndrome-in-a-6-to-9-month-old
- Early Signs of Rett Syndrome at 12–18 Months: https://pinnacleblooms.org/ask/what-are-the-early-signs-of-rett-syndrome-in-a-12-to-18-month-old
- Early Signs of Rett Syndrome in Young Children: https://pinnacleblooms.org/ask/what-are-the-early-signs-of-rett-syndrome-in-young-children
- When should I worry that my 9-to-12-month-old might have Rett Syndrome?: https://pinnacleblooms.org/ask/when-should-i-worry-that-my-9-to-12-month-old-might-have-rett-syndrome
- Early Signs of Rett Syndrome: https://pinnacleblooms.org/ask/what-are-the-early-signs-of-rett-syndrome
- Early Signs of Rett Syndrome in an 18-to-24-Month-Old: https://pinnacleblooms.org/ask/what-are-the-early-signs-of-rett-syndrome-in-a-18-to-24-month-old
- Can Rett Syndrome Be Cured?: https://pinnacleblooms.org/ask/can-rett-syndrome-be-cured
- Can Rett Syndrome Be Prevented?: https://pinnacleblooms.org/ask/can-rett-syndrome-be-prevented
- Rett Syndrome in Boys: https://pinnacleblooms.org/ask/do-boys-show-rett-syndrome-differently
- Do girls show Rett Syndrome differently?: https://pinnacleblooms.org/ask/do-girls-show-rett-syndrome-differently
- Should I be worried my child might have Rett Syndrome?: https://pinnacleblooms.org/ask/should-i-be-worried-my-child-might-have-rett-syndrome
- Early signs of Rett syndrome in a 1-year-old boy: https://pinnacleblooms.org/ask/what-are-the-early-signs-of-rett-syndrome-in-a-1-year-old-boy

### Explore causes & influences
- Are boys more likely to have Rett Syndrome?: https://pinnacleblooms.org/ask/are-boys-more-likely-to-have-rett-syndrome
- Are girls more likely to have Rett Syndrome?: https://pinnacleblooms.org/ask/are-girls-more-likely-to-have-rett-syndrome
- What Causes Rett Syndrome in Young Children?: https://pinnacleblooms.org/ask/what-causes-rett-syndrome-in-young-children
- Early Intervention for Rett Syndrome, UNCRPD & the SDGs: https://pinnacleblooms.org/ask/how-does-early-intervention-for-rett-syndrome-advance-un-child-rights-uncrpd-and-the-sdgs
- Known contributing factors for Rett Syndrome: https://pinnacleblooms.org/ask/what-are-the-known-contributing-factors-for-rett-syndrome-in-early-childhood
- Cost-effectiveness of early therapy for Rett Syndrome in young children: https://pinnacleblooms.org/ask/what-is-the-cost-effectiveness-of-early-therapy-for-rett-syndrome-in-young-children
- Prevalence and Public-Health Burden of Rett Syndrome in India: https://pinnacleblooms.org/ask/what-is-the-prevalence-and-public-health-burden-of-rett-syndrome-among-young-children-in-india

### Understand assessment
- How AbilityScore Tracks Progress in a Child with Rett Syndrome: https://pinnacleblooms.org/ask/how-does-abilityscore-track-progress-in-a-child-with-rett-syndrome
- How Rett Syndrome Is Assessed in a Young Child: https://pinnacleblooms.org/ask/how-is-rett-syndrome-assessed-in-a-young-child
- How Rett Syndrome Is Assessed in Children Under 7: https://pinnacleblooms.org/ask/how-is-rett-syndrome-assessed-in-children-under-7
- What an AbilityScore® of 0–100 means for a child with Rett Syndrome: https://pinnacleblooms.org/ask/what-does-an-abilityscore-of-0-100-mean-for-a-child-with-rett-syndrome
- What does an AbilityScore of 100–200 mean for a child with Rett Syndrome?: https://pinnacleblooms.org/ask/what-does-an-abilityscore-of-100-200-mean-for-a-child-with-rett-syndrome
- What does an AbilityScore of 200–300 mean for a child with Rett Syndrome?: https://pinnacleblooms.org/ask/what-does-an-abilityscore-of-200-300-mean-for-a-child-with-rett-syndrome
- AbilityScore 300–400 in Rett Syndrome: https://pinnacleblooms.org/ask/what-does-an-abilityscore-of-300-400-mean-for-a-child-with-rett-syndrome
- What an AbilityScore of 400–500 Means in Rett Syndrome: https://pinnacleblooms.org/ask/what-does-an-abilityscore-of-400-500-mean-for-a-child-with-rett-syndrome
- What does an AbilityScore of 500–600 mean for a child with Rett Syndrome?: https://pinnacleblooms.org/ask/what-does-an-abilityscore-of-500-600-mean-for-a-child-with-rett-syndrome
- What does an AbilityScore of 600–700 mean for a child with Rett Syndrome?: https://pinnacleblooms.org/ask/what-does-an-abilityscore-of-600-700-mean-for-a-child-with-rett-syndrome
- What an AbilityScore of 700–800 Means for a Child with Rett Syndrome: https://pinnacleblooms.org/ask/what-does-an-abilityscore-of-700-800-mean-for-a-child-with-rett-syndrome
- What an AbilityScore of 800–900 Means for a Child with Rett Syndrome: https://pinnacleblooms.org/ask/what-does-an-abilityscore-of-800-900-mean-for-a-child-with-rett-syndrome

### Explore therapy & support
- Can a Child with Rett Syndrome Attend a Mainstream School?: https://pinnacleblooms.org/ask/can-a-child-with-rett-syndrome-attend-a-mainstream-school
- Can a Child with Rett Syndrome Attend a Regular School?: https://pinnacleblooms.org/ask/can-a-child-with-rett-syndrome-attend-a-regular-school
- Can a Child with Rett Syndrome Live Independently?: https://pinnacleblooms.org/ask/can-a-child-with-rett-syndrome-grow-up-to-live-independently
- How is Rett Syndrome diagnosed in a child?: https://pinnacleblooms.org/ask/how-is-rett-syndrome-diagnosed-in-a-child
- How is Rett Syndrome supported through therapy?: https://pinnacleblooms.org/ask/how-is-rett-syndrome-supported-through-therapy
- Rett Syndrome AbilityScore®: What to Do Next: https://pinnacleblooms.org/ask/my-child-with-rett-syndrome-has-an-abilityscore-of-0-100-what-should-we-do-next
- Rett Syndrome with an AbilityScore of 100–200: your next step: https://pinnacleblooms.org/ask/my-child-with-rett-syndrome-has-an-abilityscore-of-100-200-what-should-we-do-next
- Rett Syndrome: AbilityScore 200–300 — what to do next: https://pinnacleblooms.org/ask/my-child-with-rett-syndrome-has-an-abilityscore-of-200-300-what-should-we-do-next
- Rett Syndrome: AbilityScore 300–400 — what to do next: https://pinnacleblooms.org/ask/my-child-with-rett-syndrome-has-an-abilityscore-of-300-400-what-should-we-do-next
- Rett Syndrome with an AbilityScore of 400–500: what to do next: https://pinnacleblooms.org/ask/my-child-with-rett-syndrome-has-an-abilityscore-of-400-500-what-should-we-do-next
- Rett Syndrome and an AbilityScore of 500–600: What To Do Next: https://pinnacleblooms.org/ask/my-child-with-rett-syndrome-has-an-abilityscore-of-500-600-what-should-we-do-next
- Rett Syndrome AbilityScore 600–700: What To Do Next: https://pinnacleblooms.org/ask/my-child-with-rett-syndrome-has-an-abilityscore-of-600-700-what-should-we-do-next

### At home & in everyday life
- How can I support my child with Rett Syndrome at home?: https://pinnacleblooms.org/ask/how-can-i-support-my-child-with-rett-syndrome-at-home