Symptoms

The  characteristic  behaviors of autism spectrum disorder may be apparent  in infancy (18 to  24 months), but they usually become clearer during  early childhood (24  months to 6 years).
 

As part of a well-baby or well-child visit,   your child’s doctor should perform a “developmental screening,” asking   specific questions about your baby’s progress. The National Institute  of  Child Health and Human Development (NICHD) lists five behaviors that   warrant further evaluation:

• Does not babble or coo by 12 months
• Does not gesture (point, wave, grasp) by 12 months
• Does not say single words by 16 months
• Does not say two-word phrases on his or her own by 24 months
• Has any loss of any language or social skill at any age

​Any  of these five “red flags” does not  mean your child has autism. But  because the disorder’s symptoms vary  so widely, a child showing these  behaviors should be evaluated by a  multidisciplinary team. This team  might include a neurologist,  psychologist, developmental pediatrician,  speech/language therapist,  learning consultant or other professionals  who are knowledgeable about  autism.