A child's failure to reach speech and language milestones as expected may be a "red flag," or warning, indicating a speech and language development problem. If your child does not reach developmental milestones on schedule, it does not necessarily mean there is a problem. However, he or she should be evaluated by a health professional.

Language delays include difficulties understanding what is heard or read (receptive language delays) or problems putting words together to form meaning (expressive language delays). Some children have both speech and language delays.

Red flags for a speech or language delay include:

• No babbling by 9 months.
• No first words by 15 months.
• No consistent words by 18 months.
• No word combinations by 24 months.
• Slowed or stagnant speech development.
• Problems understanding your child's speech at 24 months of age; strangers having problems understanding your child's speech by 36 months of age.
• Not showing an interest in communicating.

Also, talk to your health professional anytime you or another caregiver has concerns about your child's speech and language development or other problem that affects your child's speech or understanding of language, such as:

• Excessive drooling.
• Difficulty sucking, chewing, or swallowing.
• Problems with control and coordination of lips, tongue, and jaw.
• Stuttering that causes a child embarrassment, frustration, or difficulty with peers.
• Poor memory skills by the time your child reaches kindergarten age (5 to 6 years). He or she may have difficulty learning colors, numbers, shapes, or the alphabet.

Other red flags include:

• Failure to respond normally, such as not responding when spoken to. This may include signs that the child does not hear well, such as not reacting to loud noises.
• A sudden loss of speech and language skills. Loss of abilities at any age should be addressed immediately.
• Not speaking clearly or well by age 3.