
Many children with autism spectrum disorder show hints of the disability within the first year of life. Other children appear to develop with their peers but then suddenly — or gradually — become withdrawn and lose language skills that they already had. Most children show clear signs of autism before 2 or 3 years of age. However, some kids on the mild end of the spectrum might not be identified as having autism until later in childhood or even adolescence.
Parents of infants and toddlers on the autism spectrum may notice that their child doesn’t communicate or interact with adults and children the way that other kids the same age do. Initially, they might assume the problem lies with their child’s vision or hearing rather than a delay in their child’s development.
Below are some possible signs in the first years of life.
Early warning signs
The list below is only a guide — not a way to diagnose your child. Many children exhibit a few of these behaviors even if they don’t have autism. Some of these behaviors can also be a sign of other developmental issues. Also, a child may have autism spectrum disorder without showing all of these signs.
If you’re concerned about your child’s behavior, bring it up with your child’s medical provider. The provider can help you determine if further evaluation is necessary.
By age 12 months, a child with autism might not:
- Babble or coo
- Respond to his or her name
- React to back-and-forth interactions, such as waving or peekaboo
- Look at objects that another person is pointing to
By age 16 months, a child with autism might not:
- Say single words
By age 18 to 24 months, a child with autism might not:
- Engage in pretend play (make-believe)
By the age of 24 months, a child with autism might not:
- Say meaningful two-word phrases
- Show any interest in objects by pointing at them
There are also signs to be aware of at any age. They include:
- Losing language skills or social skills
- Avoiding eye contact
- Preferring to look at objects rather than people
- Showing a strong preference to be alone
- Having extreme difficulty with small changes in daily routines or surroundings
- Repeating words or phrases without meaning (like a parrot)
- Engaging in repetitive movements such as rocking, spinning or hand flapping
- Showing a high sensitivity to sounds, tastes, texture, lights or colors
- Not seeming to be sensitive to pain or temperature
- Showing little or no desire to be picked up or held
- Showing little interest in toys or repeatedly focusing on one aspect of a toy, such as how it feels or how one part moves
If you’re at all concerned about your child’s development or behavior, don’t keep it to yourself. Bring those concerns to your child’s medical provider. While autism is most commonly identified in children who are 3 years or older, it’s possible to screen for and diagnose the disorder in toddlers. Children who are diagnosed in the toddler and preschool years greatly benefit from early intensive intervention.
Research shows that early treatment for the disorder allows many children to function better in life, do better in school and manage their condition more successfully.

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