What to Know About New CDC Developmental Milestones for Kids

The CDC has revised the developmental milestone checklist for children, but experts raise the alarm on new changes that may cause more harm than good.

Close up of a pediatrician having a check up on her baby patient
Photo: Getty

For the first time in almost 20 years, the Center for Disease Control and Prevention (CDC) and the American Academy of Pediatrics (AAP) have updated guidelines for developmental milestones in the Learn the Signs. Act Early program. The program was created in 2004 and listed free checklists of developmental milestones for infants and warning signs of developmental delays. The recent update has new benchmarks to help parents spot developmental delays and signs of autism earlier in a child's life.

"The earlier a child is identified with a developmental delay the better, as treatment, as well as learning interventions, can begin," said Paul H. Lipkin, M.D., a member of the AAP Section on Developmental and Behavioral Pediatrics and Council on Children with Disabilities who also assisted with the revisions, in a press release issued by the AAP. "At the same time, we don't want to cause unnecessary confusion for families or professionals. Revising the guidelines with expertise and data from clinicians in the field accomplishes these goals. Review of a child's development with these milestones also opens up a continuous dialogue between a parent and the health care provider about their child's present and future development."

The revisions come after two decades of new research on child development. The decision also arrives at a time when parents are concerned about the developmental effects the COVID-19 pandemic may have had on their children. Here's everything parents need to know about the CDC milestones update.

The CDC Has Fewer Milestones for Children

In an article recently published in the journal Pediatrics, the CDC and a team of experts in child development explained when children should reach a milestone, new behaviors that should be seen at each milestone, and what factors doctors should consider for screening for developmental delays.

The new guidelines removed medical jargon and made it more reader-friendly. They also removed vague language such as "may" and "begins," to eliminate confusion on what milestones children should reach by each age and stage.

A major change to the guidelines was having fewer developmental milestones for each age. The CDC removed more than half of the milestones from the original 216 milestones across 10 checklists. These included duplicate milestones, such as "tries to use things the right way, like a phone, cup, or book," which was a noted milestone across multiple ages.

Two new checklists were added for babies at 15 months and 30 months of age. There's also a checklist for every well-child visit for children between 2 months and 5 years, bringing the total to 159 milestones across 12 checklists.

Adding and Removing Milestones

Milestones are divided into four main categories: social-emotional, language and speech, cognition, and motor. Some milestone markers have been added to show clearer signs of autism. One example of a social and emotional milestone is at 2 months, when babies should calm down when spoken to or picked up. Another is at 4 months, when most babies are smiling on their own to get attention. At 15 months, children should be able to clap when they get excited.

About one-third of milestones like fine motor skills have been bumped up to older ages. Because of the setback, children may worsen their developmental delay, making it harder to provide early intervention, explains Jessica Hatfield, MS, OTR/L, a pediatric occupational therapist for TheraTree Pediatric Therapy.

"Somebody who was originally one standard deviation below the norm, are now two standard deviations below because it's later and now I have to catch them up even more," says Hatfield. She says not catching early signs right away could snowball into other developmental problems and the financial costs of spending more time in therapy.

Another controversial change is the removal of crawling as a CDC developmental milestone. Hatfield says crawling should not have been removed because it involves multiple reflexes, from building up neck strength and control, strength for walking, and using both sides of your brain to work together. "When babies don't crawl, that's a red flag that something else might be wrong such as physiological difference in their feet/legs, reflux, inability to integrate reflexes, delay in other less obvious milestones, poor strength and muscle tone so eliminating it as a milestone could cause that red flag to be missed," Hatfield notes.

Lowering the Standard for Language Milestones

One of the biggest CDC developmental milestone changes involves language development. With this revision, the CDC delayed speech and language milestones to older ages. Before, the CDC suggested a 24-month-old would say an average of 50 words, but the new guidelines say a 30-month-old should have a vocabulary of 50 words. However, Kassie Hanson, CCC-SLP, a pediatric speech-language pathologist, says the CDC guidelines on language milestones will cause delays in identifying early developmental issues.

"You should have about 450 words between 2 and 3, so that is just wildly different," Hanson says. "I work in early intervention, so to have them make such a huge leap is really concerning because we already see too many pediatricians wait and see if [the child] might catch up." She worries the CDC's lowering of language standards will encourage more wait-and-see approaches from parents and doctors and limit the child's opportunity to get needed services earlier.

Another issue Hanson raises is that while it is correct that 24-month-olds should start combining two words, it contradicts their previous statement of children at 30 months knowing 50 words. "It's a well-known basis that you need at least 50 words before you start combining two words. So your kid is not going to start saying two-word phrases unless they have 50 or 60 words."

The American Speech-Language-Hearing Association (ASHA) released a statement on Facebook earlier this week expressing concern over the new guidelines involved in speech and language, arguing they lack scientific evidence and suggesting that the CDC work with speech-language pathologists in setting guidelines.

Lowering the standards for speech and language areas could prevent a child from getting an individualized family service plan (IFSP), says Hanson. Losing needed support could also result in a late individualized education plan (IEP) when the child starts school, delaying access to much-needed assessments and services.

Less Children Might Meet Their Milestones

Not every child reaches every milestone, and some may take longer than others. Lora Torres, OTR, an occupational therapist for the Howard Phillips Center for Children & Families, says the new CDC guidelines reflect the idea that there is a range of meeting developmental milestones.

While the new changes involve clearer benchmarks for when children develop certain behaviors, they will also raise the standard of how many children typically reach a milestone. Previous guidelines were at the 50th percentile, meaning about half of children were expected to reach that milestone by a certain age, to the 75th percentile, or at least 75 percent of children will perform that behavior.

The revision is meant to identify the remaining 25 percent who are at risk of developmental delays and give them the intervention they need sooner. "With these new guidelines, we want to catch the kids that are in that low end, and also put a family's mind at ease when the child is not really delayed, but we're tracking them closely and monitoring their milestones," said Torres.

However, there is concern that only the more extreme delays are being caught. "Those kids that fall in the 25 to 45 percentile range are no longer getting put on the radar for developmental monitoring," says Hatfield. In other words, "The tool is less sensitive and some kids could fall through the cracks."

Was this page helpful?
Related Articles