Recognizing Developmental Delays: When to Talk to Your Doctor
As a parent, you celebrate every milestone — the first smile, the first roll, the first wobbly step. But it's natural to worry when your baby doesn't seem to be hitting them "on time." The most important thing to hold onto is this: milestones are ranges, not deadlines, and healthy children arrive at them at very different speeds. That said, there are certain patterns and red flags that are worth a conversation with your pediatrician — not to alarm you, but because when a genuine delay exists, earlier support leads to better outcomes. This is not a diagnostic tool; think of it as a guide to what's worth mentioning.
What Is a Developmental Delay?
A developmental delay is when a child consistently doesn't reach their milestones within the expected age range. Delays can show up in one area or several:
- Gross motor: Using the large muscles — head control, rolling, sitting, crawling, standing, walking.
- Fine motor: Using the small muscles — grasping, transferring objects hand to hand, pointing, pincer grasp.
- Language & communication: Both understanding language (following simple directions, responding to their name) and using it (cooing, babbling, gestures, first words).
- Social & emotional: Making eye contact, smiling back, showing affection, and engaging with the people around them.
- Cognitive: Learning, problem-solving, and curiosity — exploring toys, finding a hidden object.
Why Milestones Are Ranges
The CDC and AAP describe milestones as the point by which most children (roughly 75%) can do a given skill — so being a little behind the "average" is often completely normal. What matters more than any single missed milestone is the overall pattern: Is your child steadily gaining new skills over time? Are they behind in several areas at once? Have they lost a skill they once had? Those bigger-picture questions are the ones your pediatrician cares about most.
Red Flags by Age
Early intervention is key, so here are potential red flags to watch for. For a fuller picture of what's typical at each stage, see our milestone guides for 3 months, 6 months, and 12 months.
A note for preemie parents: If your baby was born early, milestones should be measured against their corrected age (based on the due date), not their birth date, usually until about age two. Our free corrected age calculator does the math for you.
By 3 Months
- Doesn't respond to loud sounds.
- Doesn't smile at people.
- Doesn't follow moving objects with their eyes.
- Doesn't bring hands to mouth or hold their head up during tummy time.
By 6 Months
- Doesn't try to reach for things within reach.
- Doesn't roll over in either direction.
- Shows no affection for caregivers.
- Seems very stiff, or very floppy ("rag doll").
- Doesn't laugh or make squealing sounds.
By 9 Months
- Doesn't sit with support.
- Doesn't babble ("baba," "mama," "dada").
- Doesn't respond to their own name.
- Doesn't look where you point or play back-and-forth games like peekaboo.
- Doesn't recognize familiar people.
By 12 Months
- Doesn't crawl or scoot.
- Doesn't stand when supported.
- Doesn't use gestures like waving, pointing, or shaking the head.
- Doesn't say single words like "mama" or "dada."
- Loses skills they once had (this warrants prompt attention at any age).
By 18-24 Months
- Doesn't walk by 18 months, or walks only on toes consistently.
- Has few or no words by 18 months; not combining two words by 24 months.
- Doesn't imitate others or point to show you something interesting.
- Doesn't make eye contact or seems uninterested in other people.
Around 18 and 24 months, pediatricians also screen specifically for autism (often using a short questionnaire), because early signs — limited eye contact, not responding to their name, not pointing to share interest — become clearer at this age.
What to Do if You're Concerned
- Trust your gut. You know your child better than anyone. If something feels off, it's always worth raising — you will never be "that parent" for asking.
- Talk to your pediatrician. They can perform a standardized developmental screening and, if needed, refer you for a fuller evaluation.
- Keep a dated record. Note what you've observed and when. Milestone and note logging in MyBabyTracker creates a dated record you can hand to your doctor — you can start one with a free account. The app's WHO growth charts also track height and weight over time, which pairs with our free growth percentile calculator if you want a quick check. Worried specifically about speech? See when do babies start talking?
Early intervention works: If a delay is identified, your doctor can refer you to services like physical therapy, occupational therapy, speech-language therapy, or a developmental specialist. Young brains are remarkably adaptable, and the earlier a child gets targeted support, the more it helps. Seeking an evaluation is never an overreaction — it either brings peace of mind or opens the door to help sooner.
How You Can Support Development at Home
While you watch and wait for any appointment, everyday connection is the best "therapy" there is: lots of face-to-face time and conversation (narrate your day, pause for them to "reply"), daily tummy time to build strength, reading together from birth, and plenty of floor time to move and explore. These support every domain of development regardless of pace.
When to Talk to Your Pediatrician
Any of the red flags above — or your own persistent gut feeling that something is off — is reason enough to book a visit. Above all, mention it right away if your child loses any skill they previously had, at any age; that always warrants prompt evaluation. In the US, you can also self-refer to your state's free Early Intervention program (for children under 3) without waiting for a doctor's referral.
This article is for informational purposes only and is not a substitute for professional medical advice.