Babies' Firsts: The Science Behind Rolling Over

A few weeks ago, as part of our Babies’ Firsts series, we had the following questions for our readers:

1. How old was your baby when he or she rolled over for the first time?
2.  Did your baby roll from back-to-tummy or tummy-to-back first and how long did it take before he or she could roll both ways?
3. What kind of adjustments or modifications did you have to make in your baby's environment to accommodate his or her new skill?

First, we’d like to thank everyone who commented! Your stories show that every baby is different and that even siblings who grow up in the same environment achieve milestones, like rolling over, at their own pace. Today, I’ll share the story about when my youngest daughter, Charlotte, learned to roll over and then explain what research shows about how and when babies tend to develop this important skill.

Charlotte’s Story
Charlotte is 7 months old now and she’s been rolling over for 3 ½ months. She first rolled from her back to her tummy while we were playing together on the floor. Although we had been having “tummy time” a few times each day, she never seemed to like it, so when she first rolled over, she promptly started crying. I helped her roll back onto her back, but within just a few minutes she was back on her tummy again. It went on like this for a few weeks until she learned to roll from her tummy to her back.

We had to make quite a few changes when Charlotte started rolling over. We had to be much better about keeping the floor clean and making sure that her big sister, Olivia, picked up her toys. We also had to start keeping all the dog toys out of reach and I bought a foam play mat to make our hard floor a little softer for her. All of the effort came in handy, because before long she was army crawling all over the house (but that story is for another post!).

Rolling Over Research
Everyone knows that there are 2 ways babies must learn to roll, from back-to-tummy and tummy-to-back, but many people (including me, until today) may not know that within each of these rolling methods there are 2 types, with and without rotation. Here is information about each type:

Prone to supine (tummy-to-back)

• Without rotation – Rolling from tummy-to-back without rotation means that the shoulder and pelvis are aligned, body is extended, and the movement starts from the head.  It can start as early as 1 month of age, but only about 10% of babies can roll this way by 3 months; 50% and 90% achieve it by 6 and 8 ½ months, respectively.    
• With rotation – Rolling from back-to-tummy with rotation is characterized by a shoulder and pelvis that are not aligned, movement originating from the shoulder, pelvis, or head, and rotation in the body.  Because the rotation is a more complicated movement, this type of rolling typically starts around 4 months with 50% achieving it by 7 months and 90% by about 9 months.

Supine to prone (back-to-tummy)

• Without rotation – When a baby rolls from back-to-tummy without rotation, his head will be up, his body will be stretched and his shoulder will be in line with his pelvis. The movement will begin from the head, shoulder or hip, and his body will move as one unit. Fifty percent of babies can roll this way by about 5.5 months and 90% reach this milestone by 9 months.
• With rotation – Rolling this way requires the baby to lift his head and stretch his body and the movement starts from the head, shoulder, or hip, but the shoulder and pelvis will not be aligned, the baby’s body will rotate, and the legs will move separately from the rest of the body. Just as with tummy-to-back, rolling with rotation is mastered a little later than rolling without; 50% achieve it by 7 months and 90% by 9 months.

So, the take-away message: The age at which babies master rolling over varies greatly! If you think about it, it makes sense given that rolling over requires the coordination and use of many muscle groups.  Regardless of the age of your baby, rolling over means that you have some baby-proofing to do! For more information, refer to Baby Proofing Part 1 (for birth to 6 months) and Part 2 (for 6-12 months).

Reference:
Piper M, Darrah J. Motor Assessment of the Developing Infant. Philadelphia PA:W.B. Saunders Company 1994.

Baby Proofing by Baby’s Stages Part 2: 6-12 months

Welcome back! Today’s post is part 2 in a series focused on using your baby’s developmental stages to help baby-proof his environment. Now let’s take a look at the older baby, age 6-12 months. Note: If your baby is just now moving into his crib, review part 1 of this blog for links to check crib safety.

6-7 months
Your baby may have mastered rolling as an efficient mode of transportation or he may be getting ready to crawl. Warning! If you haven’t already completely baby-proofed your home, now is the time. Your baby’s instinct will be to poke, hold, and taste anything and everything he comes across. Almost everything that is small enough to pick up can end up in your baby’s mouth. The 6-7 month old is also learning to have more control over his body movements. What does this mean for you? Your baby will be even more explorative because he has an innate drive to practice his newfound motor skills (rolling, crawling, etc.) almost constantly. Here are a few specific tips to keep him safe:

• Remove any hanging toys from the crib when you notice your baby can reach up and touch them.
• Put outlet covers on all outlets; even those hidden behind furniture. Little arms and fingers can find their way into the smallest of holes.
• Lock cabinets; especially those that contain any poison or chemical that could be ingested.
• If unable to lock cabinets, remove all poisons and chemical cleansers to a safer location; like the garage. This includes medications, alcohol and even vitamins.
• Clear all objects off coffee tables, or other low furniture. Even magazines and newspapers can be a hazard. Babies will be able to tear pages and it will almost always end up in their mouths. This can be a choking hazard.
• A good rule to follow: if an object can fit through a toilet paper roll, it is a choking hazard and can get stuck in your baby’s throat. These items should be placed in a locked drawer or up out of the reach of your child.
• Keep pet food (if any) out of the reach of the baby. This might sound like a silly tip, but I can attest from experience that your baby will be drawn to your dog’s bowl of puppy chow. It’s amazing how quickly they can move towards the food and pop a few pieces in their mouths!

8-10 months
Many babies this age are beginning to pull up on furniture (or people) to get themselves from a sitting to a standing position. With this new ability comes a brand new perspective of his world! Soon he will be walking along furniture and exploring everything that is in his new line of vision. Baby proofing must now be taken to the next level.

• As soon as your baby can get up on all fours he could use the crib bumper pad as a step to climb out. Remove it from the crib.
• Coffee tables and other furniture that babies could pull themselves up on should be cleaned off completely. Babies can pull heavy objects over on themselves easily or put things they find lying about into their mouths.
• Furniture that can be potentially pulled over onto baby should be secured to the wall (upright book case, TV, etc.)
• Double check outlets and cords. Remember, pulling up brings baby to a new height!
• Watch sharp corners on furniture or any sharp object that is just the right height for head bumping. There are soft, non-permanent corner covers available for corners of tables. Or move the offending piece of furniture elsewhere for a while.

12 months
Most babies are learning to take steps and some are walking pretty well by this time. Again, more mobility leads to more exploring! Babies become little scientists, exploring and testing the world around them. When it comes to walking and movement, 12-month-olds often have a one track mind. It is common for babies this age to focus all of their energy on perfecting their newfound skill, leaving little time for eating, sleeping, or getting their diapers changed.
Now that your baby is more mobile, you may want to consider the following tips in addition to those mentioned earlier in this post:

• Keep the bathroom doors closed or purchase toilet locks
• Make sure breakables are completely out of reach. Remember babies are stronger and more mobile now!
• Do not leave sharp objects such as scissors, clippers, pens and pencils within your baby’s reach.

Other Resources
For more information about keeping your environment safe for your child visit: www.safekids.org.
For information on crib safety click here.
For information on recalled baby items click here.

Next time: Reasons for Reading to Your Baby!

Baby Proofing by Baby’s Stages -Part 1: Birth-6 months

By Jennifer Goldbronn, RD

Knowing about your baby’s developmental stages can help you baby-proof your home effectively. By anticipating how your baby’s development will affect his ability to explore his surroundings, you can be ready for almost anything! Now let’s get down to your baby’s level (physically, at least) and see what potential dangers lurk around your baby’s environment. Remember, baby-proofing alone does not ensure your child will be completely safe; so never leave your baby unattended.

Birth-4 weeks
At this age, baby-proofing your house may seem unnecessary since your new arrival isn’t very mobile yet. However, it is always better to be prepared before your baby reaches the next stage of development. You will be amazed how quickly your baby will grow and begin to explore. The best way to begin the baby-proofing process is to get down to your baby’s level. Crawl around your home and you will quickly find dangerous places where little bodies could get injured or unsafe objects that little fingers could grab. Your baby may not be able to move much yet, but it won’t be long before he is up and walking and finding ways to get into things. Here are a few more safety tips to keep in mind:

• Never leave your baby unattended! Newborns are born with the ability to move their arms and legs in a swimming motion and lift their heads when placed on their stomachs. Do not assume that a newborn is safe while lying on a changing table or bed (even king size beds)!


• When your baby is on the changing table make sure to use the safety belt to avoid accidents.


• Be sure to remove all blankets and pillows if your baby is lying on a bed. Also, an adult should always be close by in the same room.


• Babies begin to explore objects by mouth as soon as 1 month old. Remember to check the objects near your baby to make sure they are safe, soft and no smaller than a toilet paper roll in diameter.


• Before buying a crib, review the following crib safety tips published by the Consumer Product Safety Commission (CPSC).


• Use caution when buying used baby items or using hand-me-downs. The CPSC has also launched a campaign to keep dangerous used children’s products out of thrift and consignment stores and off the internet, click here for more information.

6-8 weeks
By 6-8 weeks of age, your baby’s neck is growing stronger, and he is able to hold his head up for longer amounts of time. His ability to reach for and grasp objects consistently is right around the corner! With so many possibilities for movement, it is still very important to never leave your baby unattended. Never leave a young baby on an adult bed, couch, or other high surface. You won’t believe how far they can move, long before they can roll or crawl!

4-5 months
By 4 or 5 months of age, babies are learning to sit with support and to use their hands to balance while sitting. They may also start rolling over and can quickly figure out how to use rolling to transport them from one area of a room to another. Babies start to reach for objects and learn how to transfer them from one hand to the other. Babies always seem to find your cell phone or the remote control to the TV around this age, and they will suck and chew on them until you can't make a call or are unable to change the channel! All of this means that your baby’s ability to explore his surroundings just got a lot easier.

• Keep breakables up and out of your baby’s ever-extending reach


• Shorten or remove any cords, especially around window blinds


• Block the fireplace and use gates near stairs or other unsafe areas


• Think twice when putting baby down. Your baby can easily roll off of any elevated surface at this age.

Your baby’s first 6 months will fly by (if they haven’t already). Now it’s time to prepare for the second half of your baby’s first year. Next time we’ll explore how to continue the baby-proofing process as your older baby develops and becomes even more mobile.

Next time: Part 2: Baby Proofing by Baby’s Stages - 6-12 months