When Lily Vasey was an infant, her mother, Kate, assumed she'd hit all her milestones on time, just as her older son, William, had. But when Lily turned 6 months -- the average age when babies begin to crawl -- she showed no signs of doing so. Instead, she'd pull herself along the floor, as her mom describes, "like a soldier slogging through mud." "Her pediatrician told me she was okay, and as each month went by, I just figured she'd crawl the next one," says Vasey, of Rochester, New York. But Lily, now 3, never did. She dragged herself with her arms until she started walking at 14 months. "It was very surprising -- I never expected that my daughter would skip such a big milestone," says Vasey.
Lily's story isn't even that unusual. According to experts, more kids seem to be hitting numerous motor (movement) development milestones later or skipping them altogether. The topic is increasingly becoming controversial in the medical community. While the conventional wisdom is that there's no harm in skipping the crawling stage, a growing number of experts -- particularly pediatric occupational therapists -- say that crawling is actually a critical developmental milestone whose long-term benefits we're only now beginning to recognize. We spoke to nearly 20 authorities on both sides of the issue to get the scoop on this heated debate.
A significant achievement
In 1994, several national health organizations, including the American Academy of Pediatrics, started encouraging parents to put babies to sleep on their backs to help prevent sudden infant death syndrome (SIDS). The lifesaving outcome: The incidence of SIDS has decreased more than 50 percent. But according to several studies, an inadvertent result of the campaign is that more kids are achieving motor milestones later, or bypassing them altogether, because their upper bodies aren't as strong due to lack of time spent on their stomachs. When babies skip crawling -- and by this we mean the classic hands-and-knees crawl -- then they miss out on more opportunities to develop that strength and wind up with weaker upper body muscles.
"Crawling helps strengthen the hands, wrists, elbows, and shoulders because babies have to constantly activate them to support their body weight," says Felice Sklamberg, a pediatric occupational therapist at New York University's School of Medicine. "We're seeing that because non-crawlers aren't as strong, they have a harder time as older children pulling themselves out of a pool, climbing a jungle gym, or even picking themselves up from the floor."
Skipping this milestone can also affect a child's ability to hold silverware or a pencil down the road, since the weight-bearing experience of crawling helps develop arches and stretch out ligaments in the wrist and hand that are needed for fine motor skills. "During the crawling period, the large joint at the base of the thumb is expanded into its full range of motion, so noncrawlers may have messier handwriting, for example," explains Mary Benbow, an occupational therapist and a leading expert on pediatric hand development.
Crawling is a unique experience in other ways as well. "It's a real step up for coordination because it's the first opportunity to practice bilateral coordination -- using the arms and legs in reciprocal movements," says Jane Case-Smith, director of the division of occupational therapy at Ohio State University's School of Allied Medical Professions in Columbus and an early-intervention specialist. "This skill is used in activities like getting dressed, self-feeding, and sports. A child who sidesteps crawling may have more of a struggle catching up."
Babies who skip any kind of scooting or dragging miss out on the benefits of being on the floor as well. "Children learn through interaction with their hands. They don't get as much if they go straight to walking, because then they need to use their hands for balance," says Karen Hendricks-Muñoz, M.D., chief of neonatology and associate professor of pediatrics at New York University's School of Medicine. "Navigating on the ground also helps visual spatial skills and depth perception develop more quickly."
Lack of proof
Though many experts will attest to the importance of crawling, others adamantly argue that skipping it is no big deal. "It's a prominent misconception that it's important for kids to include crawling in their development," says Pamela High, M.D., director of developmental-behavioral pediatrics at Hasbro Children's Hospital in Providence, Rhode Island, and a professor of pediatrics at Brown Medical School. "Before parents freak out because their child doesn't crawl, we need to have data that kids who don't will have any long-term negative developmental consequence, and there currently is none," she says. "It remains conjecture."
As far as the short term is concerned, studies have shown that crawling does not seem to be predictive of other early developmental milestones, such as standing and walking. One study published in Pediatrics found that while babies who slept on their backs were twice as likely not to crawl as stomach sleepers, all were walking by around their first birthday, regardless of how they slept or if they had crawled.
In fact, crawling isn't listed on the Denver Development Screening Test, a tool used by pediatricians to measure children's development, because the skill is so variable. "As long as your child has some form of locomotion by the time he's nine months old, he's probably fine," explains Ari Brown, M.D., a pediatrician in Austin, Texas, and the author of Baby 411: Clear Answers and Smart Advice for Your Baby's First Year. "Bypassing one milestone is not usually a cause for concern, but if a baby skips more than one or seems to only engage one side of his body, then it's important to discuss it with your doctor."
Tummy to play
No matter where experts stand on the crawling issue, one point they all agree on is the importance of tummy time.
In fact, in 2000, many SIDS advocacy organizations added "Tummy to Play" to their "Back to Sleep" slogan due to the growing number of babies with flattened heads and infants who weren't achieving motor milestones as quickly. But it seems that many parents are forgetting the tummy part of that equation. "Moms are so panicked about SIDS that they don't want to risk putting their babies on their stomachs even during the day when they're awake," says Benbow. "When they do, the babies cry because they aren't used to it -- so parents are reluctant to force the issue."
In other words, many babies might not be crawling simply because they don't have the opportunity to do so. With the popularity of activity centers, swings, and jumpers and the hours spent in car seats and strollers, the likelihood that they'll learn to crawl is even slimmer. Sometimes all it takes is giving them supervised tummy time each day so they have a chance to practice. "Put them on the floor and give them time to chase a ball or reach for a favorite toy," says Dr. Brown. "They'll learn how to use their muscles, unless they were predisposed to having a developmental delay to begin with."
Lastly, keep in mind that there's no need to push children to achieve any particular milestone faster -- especially walking. "You can't force children to crawl, but you don't have to speed up the process in their learning to walk either," says Sklamberg, who adds that babies can benefit from any time spent crawling, even a few weeks. "Though there's little scientific proof that crawling is important, there are plenty of experts who believe it is -- so what's the harm in doing tummy time and letting nature take its course?"