Developmental Delays in Babies: Red Flags and When to Seek Help

Q: How long does an early intervention evaluation take?

The evaluation itself typically takes 1 to 2 hours. Federal law requires that the entire process, from referral to completed evaluation, be finished within 45 days. Results and recommendations are discussed with parents at the end of the evaluation or shortly after.

Q: What if my child has delays in only one area?

A delay in a single area still qualifies for evaluation and potentially services. Even an isolated delay is worth addressing because developmental domains are interconnected. For instance, a speech delay can affect social interaction, and a motor delay can limit exploration and cognitive development.

As a pediatrician, one of the most common conversations I have with parents begins with the words, “Should I be worried?” Every baby develops at their own pace, and the range of “normal” is wide. However, there are certain milestones and patterns that, when absent, warrant a closer look. The good news is that early identification and intervention can make a profound difference in a child’s developmental trajectory.

This guide walks you through what developmental delays actually mean, what to watch for at each age, and exactly how to take action if something concerns you.

What Is a Developmental Delay vs. a Developmental Disorder?

These terms are often used interchangeably, but they are distinct:

Developmental delay means a child has not reached one or more milestones by the expected age. Delays can be temporary — some children simply need more time and catch up on their own, particularly with support.
Developmental disorder (or disability) is a more persistent condition that typically affects a child throughout their life. Examples include autism spectrum disorder (ASD), cerebral palsy, Down syndrome, and intellectual disability.

A delay does not automatically mean a disorder is present. However, persistent delays across multiple areas, especially when they are not improving with time and support, may be early signs of an underlying condition that benefits from diagnosis and targeted intervention.

Types of Developmental Delays

Delays can occur in one or more of the following domains:

Gross and Fine Motor Delays

Gross motor: Delays in rolling, sitting, crawling, pulling to stand, walking, or running
Fine motor: Difficulty grasping objects, transferring items between hands, picking up small objects with a pincer grasp, or using utensils

Speech and Language Delays

Receptive language: Difficulty understanding words, following directions, or responding to their name
Expressive language: Limited babbling, few or no words, inability to combine words by expected ages

Cognitive Delays

Difficulty with problem-solving, cause-and-effect understanding, object permanence, or imitation
Limited curiosity or exploration of the environment

Limited eye contact, social smiling, or interest in other people
Difficulty with back-and-forth interaction (social reciprocity)
Excessive difficulty with transitions or emotional regulation beyond what is typical for age

Red Flags by Age: What to Watch For

The following milestones are based on the CDC’s updated “Learn the Signs. Act Early.” developmental milestone checklists. These are not “average” milestones but rather the ages by which most children (approximately 75%) should have achieved them. Missing multiple milestones at any age is a stronger concern than missing one.