Movin' and Groovin'
For the first six months of life, your baby has relied on you to set him in motion. You've carried him, rocked him, propped him up with pillows, and danced with him on your lap. Now he's driven to move and groove on his own.
Here's a typical scenario: Your 7-month-old is sitting up on her own and reaches across her body to grab at a toy. The act of reaching causes her to lose her balance. In an attempt to right herself, she twists her body and thrusts her hands out in front of her, landing on her tummy. Once on the floor, she may raise her head and gather her knees, as well as her hands, under her. She's on the runway in crawling position!
Set in Motion
Of course, "crawling" means different things to different babies. Another baby may, from a sitting position, discover that she can push her hands against the floor and scoot on her bottom to get from here to there. Regardless of her style, her first attempts may not lead to any forward movement -- she may try pushing her palms on the floor and find herself moving backward instead.
Indeed, it takes a while to get good at anything, and crawling is no exception. According to New York University psychologist Karen E. Adolph, PhD, who has conducted numerous studies on the topic, crawling speed increases by a staggering 720 percent over the first 20 weeks of learning, while the size of an infant's crawling "steps" increases by 265 percent. In other words, once she gets the hang of things, watch out: Crawlers can move!
Learning the Lay of the Land
Crawling doesn't merely boost physical skills. As your baby learns to move independently, she will become more aware of her surroundings and better able to navigate them, says Lise Eliot, PhD, author of What's Going on in There? How the Brain and Mind Develop in the First Five Years of Life (Bantam). There's a big difference between being carried around and getting somewhere yourself. Crawling helps kids learn to keep track of locations and use landmarks to orient themselves -- for example, she gets to her basket of toys by looping around the coffee table and heading toward the kitchen. "It's like the difference between driving the car and just riding along," says Eliot.
In addition, the very act of balancing in different positions takes place in the context of her own rapidly changing body. Her arms and legs might actually be longer from one month to the next, and she may weigh more. Further complicating the mix, as baby's skills become more advanced, her abilities change. In one of her studies, Adolph gathered a group of 9-month-olds who had been sitting up for a while but had only just started to crawl. In the first scenario, the babies were placed on a platform in view of a bright red ball 2 feet below. In their excited pursuit of the ball, the babies would have fallen off the platform if no one had caught them. Yet when they were seated with their legs dangling over the edge of the platform, the babies gazed at the tempting red ball but didn't reach for it because they knew they would fall.
Why were the babies more cautious in the second instance? The 9-month-old babies, with several months of sitting experience, knew what they could and couldn't do from that position. On the other hand, as novice crawlers they lacked both the depth perception and hand-eye coordination to judge their own abilities correctly during the precarious new activity.
In short, every new motor milestone involves learning how to balance and move in a different way, requiring constant fine-tuning of their bodies as they try new tasks.
What If My Baby Doesn't Crawl?
Not all babies crawl before they learn to walk. In general, babies are achieving motor milestones at a later age than they did 15 or 20 years ago, in part because most of them are now put to sleep on their back. The Back to Sleep campaign has significantly reduced the risk of SIDS, but the unintended fallout is that babies spend less time on their stomach. Experts recommend giving baby tummy time during the day so he has a chance to build upper-body strength. Still, some babies won't tolerate being facedown, and others are just destined not to crawl. The good news is that there's no evidence that babies suffer motor-skill delays if they don't crawl. The important thing isn't so much the crawling but giving your baby lots of chances to build up his muscles and experience the world from different views.
In the Mouths of Babes
No matter how often you clean your floor, you'll still find yourself pulling small objects out of your baby's mouth. If there's a lost button on the floor, you can count on him to find it!
These explorations are a normal part of development. Babies begin to explore the world with their mouth even before birth; ultrasounds routinely show fetuses sucking their thumb as early as 16 weeks. At birth, sensations in and around the mouth are the most highly developed, so once babies can grasp things, they're eager to experience size, shape, and texture by putting every object to the taste test. Mouthing peaks between 7 and 9 months and then declines steadily as babies become more adept at using their hands. One study, by Jonathan Roberts and Martha Ann Bell at Virginia Polytechnic Institute and State University, in Blacksburg, noted that 8-month-old boys spend more time mouthing toys than girls of the same age. They attribute this to "faster brain maturation of female infants, who spend more time examining toys with their eyes."
While baby's in this stage, keep potential choking hazards away, and let him enjoy his hold on the world's delights and learn as he goes ... or chews.
Where Did Mommy Go?
Ironically, just as a baby learns to crawl and can get away from you, he may also realize that he's terrified if you're out of his sight. He often brings this on himself by crawling into another room or rounding a corner. Of course, his hysteria at being separated from you (or any other trusted primary caregiver) can also be brought on when you leave, even if he's in the care of someone he knows. This phenomenon of being so attached to one person that a baby mistrusts all others is called separation anxiety. Most babies experience it in varying degrees between 7 and 9 months, even if they were chortling in the arms of any stranger just a month ago.
Don't worry, though. Separation anxiety is a sign that your baby is emotionally attached to you, and that, of course, is a very positive development.
From the Doctor
Pediatrician Sarah DuMond, MD, recommends: Take a couple of small toys from home with you to your next well-baby visit. They'll keep your little one busy while you're waiting, but they're also great tools for doctors to assess your baby's fine motor development. She's much more likely to demonstrate how well she transfers objects from one hand to another, or picks something up with a pincer grasp, if she has her own familiar rattle or toy instead of a boring reflex hammer or unfamiliar office toy.
Holly Robinson lives with her five children outside of Boston.
Originally published in the December 2006 issue of American Baby magazine.
All content here, including advice from doctors and other health professionals, should be considered as opinion only. Always seek the direct advice of your own doctor in connection with any questions or issues you may have regarding your own health or the health of others.