Behavior & Social

Autistic Regression - Losing Skills

Medically reviewed by Dr. Emily Torres, PhD, CCC-SLP · Pediatric Speech-Language Pathologist

Content reviewed against published AAP, NIH, CDC guidelines

Editorial policy

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Behavioral development varies greatly from child to child. If you have noticed autistic regression - losing skills, here is what you need to know.

The short answer

Approximately 25 to 30% of children later diagnosed with autism experience a regression, losing previously acquired skills between 15 and 24 months. This most commonly affects language and social skills. Any loss of skills at any age requires prompt medical evaluation. While regression can occur in autism, it can also indicate other medical conditions that need to be ruled out.

Key takeaways

  • Approximately 25 to 30% of children later diagnosed with autism experience a regression, losing previously acquired skills between 15 and 24 months. This most commonly affects language and social skills. Any loss of skills at any age requires prompt medical evaluation. While regression can occur in autism, it can also indicate other medical conditions that need to be ruled out.
  • Usually normal when: Your child temporarily uses fewer words during illness or major life changes but bounces back
  • Call your doctor if: Your child has lost words AND social engagement simultaneously
  • Varies by age — see the age-by-age breakdown below

This is one of the most common questions parents ask. Searching for answers means you care.

What Parents Should Know

According to AAP, NIH, CDC guidelines, approximately 25 to 30% of children later diagnosed with autism experience a regression, losing previously acquired skills between 15 and 24 months. This most commonly affects language and social skills. Any loss of skills at any age requires prompt medical evaluation. While regression can occur in autism, it can also indicate other medical conditions that need to be ruled out. At 12-15 months, regression before 15 months is less common but can occur. Skills that may be lost include babbling, eye contact, social smiling, and gestures. Any skill loss at this age should be reported to your pediatrician immediately. It is generally considered normal when your child temporarily uses fewer words during illness or major life changes but bounces back. However, you should contact your pediatrician promptly if your child has lost words AND social engagement simultaneously.

Sources: [1], [2], [3]

Normal vs. Concerning

Usually Normal
Worth Discussing
Your child temporarily uses fewer words during illness or major life changes but bounces back
Your child has lost words AND social engagement simultaneously
Your child seems to forget a word for a few days but then uses it again
Any sudden or significant loss of previously acquired skills at any age requires immediate evaluation
Your child's skills fluctuate slightly but overall trajectory is upward
Your child has lost multiple words they were using consistently

By Age

What to expect by age

12-15 months

Regression before 15 months is less common but can occur. Skills that may be lost include babbling, eye contact, social smiling, and gestures. Any skill loss at this age should be reported to your pediatrician immediately.

15-24 months

This is the most common window for autistic regression. A child who was saying words may stop talking. A child who was socially engaged may become withdrawn. These changes often happen gradually but can seem sudden.

24-36 months

Regression after 24 months is less typical for autism and other causes should be investigated thoroughly. Medical evaluation should include neurological assessment and EEG to rule out conditions like Landau-Kleffner syndrome.

3-4 years

Following evaluation and diagnosis, intensive early intervention should begin promptly. Research shows that children who regress can make significant gains with appropriate therapy, especially when started early.

4-5 years

With consistent therapy, many children who experienced regression regain skills and continue to develop. The trajectory varies widely, and some children make remarkable progress.

What to Tell Your Pediatrician

  • Describe when you first noticed autistic regression - losing skills and how it has changed over time.
  • Note your baby's current age and which age-specific patterns you are seeing.
  • Mention if your child has lost multiple words they were using consistently.
  • Mention if your child has become less socially engaged or stopped responding to their name.
  • Let your doctor know if you have noticed any related concerns, such as changes in feeding, sleep, or movement patterns.
  • Bring a list of any questions or observations you want to discuss at the appointment.

What Should You Do?

When to take action

Probably normal when...
  • Your child temporarily uses fewer words during illness or major life changes but bounces back
  • Your child seems to forget a word for a few days but then uses it again
  • Your child's skills fluctuate slightly but overall trajectory is upward
Mention at your next visit when...
  • Your child has lost multiple words they were using consistently
  • Your child has become less socially engaged or stopped responding to their name
  • Your child has lost motor skills, play skills, or self-help skills
Act now when...
  • Your child has lost words AND social engagement simultaneously
  • Any sudden or significant loss of previously acquired skills at any age requires immediate evaluation

What You Can Do at Home

  • Keep track of when you notice autistic regression - losing skills — noting the time of day, duration, and any triggers can help your pediatrician.
  • Remember that your child temporarily uses fewer words during illness or major life changes but bounces back — this is generally within the range of normal.
  • At 12-15 months, focus on observation rather than intervention unless your pediatrician advises otherwise.
  • Respond consistently and calmly to your baby's behavior. Maintain predictable daily routines.
  • While monitoring at home, seek immediate care if your child has lost words AND social engagement simultaneously.

My Baby Is Losing Words or Skills

If your child was consistently using words and has truly stopped, this is something to act on promptly. Regression - the genuine loss of skills a child previously had - is different from a normal plateau or a toddler being too busy to talk, and it always warrants a conversation with your pediatrician sooner rather than later.

Child Losing Speech or Language Regression

Losing words or language skills that your child previously had - known as language regression - is always worth taking seriously. While some temporary "quiet periods" can occur when a toddler is focused on a new skill like walking, true loss of words (especially multiple words over weeks) should be evaluated promptly. About 25-30% of children later diagnosed with autism experience some form of language regression.

Autism Signs Appearing After 18 Months

While some children show signs of autism from early infancy, others develop typically until 12 to 24 months before differences emerge. This can involve regression (losing skills) or plateau (skills stop progressing while peers advance). Late-appearing signs are valid and important to recognize. If you notice changes in your child's development after 18 months, request evaluation.

Milestone

Milestone Checklists by Age

Track your baby's developmental milestones from birth to 5 years with age-specific checklists.

Milestone

Month-by-Month Development

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Guide

When to Call the Doctor

General guide on when to call the pediatrician, visit urgent care, or go to the ER.

Frequently asked questions

Is autistic regression - losing skills normal?
Approximately 25 to 30% of children later diagnosed with autism experience a regression, losing previously acquired skills between 15 and 24 months. This most commonly affects language and social skills. Any loss of skills at any age requires prompt medical evaluation. While regression can occur in autism, it can also indicate other medical conditions that need to be ruled out.
When should I call the doctor about autistic regression - losing skills?
Your child has lost words AND social engagement simultaneously Any sudden or significant loss of previously acquired skills at any age requires immediate evaluation
When is autistic regression - losing skills normal?
Your child temporarily uses fewer words during illness or major life changes but bounces back Your child seems to forget a word for a few days but then uses it again Your child's skills fluctuate slightly but overall trajectory is upward
What causes autistic regression - losing skills?
Approximately 25 to 30% of children later diagnosed with autism experience a regression, losing previously acquired skills between 15 and 24 months. This most commonly affects language and social skills. Any loss of skills at any age requires prompt medical evaluation. While regression can occur in autism, it can also indicate other medical conditions that need to be ruled out. Common explanations include: Your child temporarily uses fewer words during illness or major life changes but bounces back. Your child seems to forget a word for a few days but then uses it again.
What should I mention to my pediatrician about autistic regression - losing skills?
You should mention autistic regression - losing skills at your next visit if: Your child has lost multiple words they were using consistently. Your child has become less socially engaged or stopped responding to their name. Your child has lost motor skills, play skills, or self-help skills.
Is autistic regression - losing skills normal at 12-15 months?
Regression before 15 months is less common but can occur. Skills that may be lost include babbling, eye contact, social smiling, and gestures. Any skill loss at this age should be reported to your pediatrician immediately.
Is autistic regression - losing skills normal at 15-24 months?
This is the most common window for autistic regression. A child who was saying words may stop talking. A child who was socially engaged may become withdrawn. These changes often happen gradually but can seem sudden.
Should I go to the ER for autistic regression - losing skills?
Seek emergency care if your child has lost words AND social engagement simultaneously, or if any sudden or significant loss of previously acquired skills at any age requires immediate evaluation. When in doubt, call your pediatrician's after-hours line for guidance.
Does autistic regression - losing skills go away on its own?
In many cases, autistic regression - losing skills resolves on its own, especially when your child temporarily uses fewer words during illness or major life changes but bounces back. By 4-5 years, with consistent therapy, many children who experienced regression regain skills and continue to develop. The trajectory varies widely, and some children make remarkable progress.
AAPNIHCDC

References

  1. [1]American Academy of Pediatrics. Autism Regression. HealthyChildren.org. AAP
  2. [2]National Institute of Mental Health. Autism Spectrum Disorder. NIH
  3. [3]Centers for Disease Control and Prevention. Signs and Symptoms of Autism. CDC

Doctor Visit Checklist

Bring this checklist to your next pediatrician visit to discuss Autistic Regression - Losing Skills.

Things to mention

  • Describe when you first noticed autistic regression - losing skills and how it has changed over time.
  • Note your baby's current age and which age-specific patterns you are seeing.
  • Mention if your child has lost multiple words they were using consistently.
  • Mention if your child has become less socially engaged or stopped responding to their name.
  • Let your doctor know if you have noticed any related concerns, such as changes in feeding, sleep, or movement patterns.
  • Bring a list of any questions or observations you want to discuss at the appointment.

Observations to share

  • Your child has lost multiple words they were using consistently
  • Your child has become less socially engaged or stopped responding to their name
  • Your child has lost motor skills, play skills, or self-help skills

Urgent signs to report immediately

  • Your child has lost words AND social engagement simultaneously
  • Any sudden or significant loss of previously acquired skills at any age requires immediate evaluation

My notes

From ismybabyalright.com — free, evidence-based baby health guides

All content follows our editorial policy and is reviewed against published clinical guidelines.

2,705 evidence-based guides6 authoritative medical sources5 medical advisory board members

Related Resources

Milestone ChecklistsEarly Intervention DirectoryBaby Sign Language GuideBaby Tracker

Bottom line

Most cases of autistic regression - losing skills are normal. Talk to your pediatrician if your child has lost words and social engagement simultaneously.

Trust your instincts. If something feels wrong, reach out to your pediatrician. Worrying about your baby means you care — that is a good thing.

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My Baby Is Losing Words or Skills

If your child was consistently using words and has truly stopped, this is something to act on promptly. Regression - the genuine loss of skills a child previously had - is different from a normal plateau or a toddler being too busy to talk, and it always warrants a conversation with your pediatrician sooner rather than later.

Child Losing Speech or Language Regression

Losing words or language skills that your child previously had - known as language regression - is always worth taking seriously. While some temporary "quiet periods" can occur when a toddler is focused on a new skill like walking, true loss of words (especially multiple words over weeks) should be evaluated promptly. About 25-30% of children later diagnosed with autism experience some form of language regression.

Autism Signs Appearing After 18 Months

While some children show signs of autism from early infancy, others develop typically until 12 to 24 months before differences emerge. This can involve regression (losing skills) or plateau (skills stop progressing while peers advance). Late-appearing signs are valid and important to recognize. If you notice changes in your child's development after 18 months, request evaluation.

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