Do infant seats leave too little "tummy time" for tots?

For the first six months of my daughter's life, there were three items I couldn't do without: a nursing pillow, a front carrier pack, and the all-important bouncy chair. Although I carried Maddy much of the time, I relied on the chair for a safe place to put her when my back needed a break, a meal needed cooking or my preschool son needed extra attention.

For many parents like me, chairs, swings and other strap-in seats are undeniably convenient. But they could be costing our babies developmentally important "tummy time," according to the American Physical Therapy Association (APTA).

The APTA says that many babies are spending too much of their waking time on their backs and not enough time on their stomachs. And a lack of tummy time can delay infants' muscle development and mobility. The APTA cites a recent survey of 400 physical and occupational therapists in which two-thirds had seen an increase in early motor delays among infants over the past six years. An early motor delay happens when a child isn't able to meet important physical milestones in the first months and years of life. More than 80 percent of therapists listed a lack of tummy time as the No. 1 reason for this increase.

A decrease in tummy time could be partly due to the successful "Back to Sleep" campaign, which has led to more than a 50 percent drop in sudden infant death syndrome (SIDS) by reminding parents to put their babies to sleep on their backs. But a reliance on strap-in seats and carriers could also be responsible, says the APTA. Today, many of these are designed for maximum convenience, with car seats doubling as infant carriers that can then be fastened directly onto strollers and swings. This means some infants are spending extended periods on their backs without any change in position, let alone time on their tummy.

The connection between strap-in seats and less tummy time makes logical sense, but it's important to note that this connection is based on expert opinion and observation, not scientific research. So we don't know whether babies who spend long stretches in seats are, in fact, getting less time on their stomach. We also can't say for sure whether there has been a recent increase in early motor delays caused by a lack of tummy time, as this information comes from a survey of therapists rather than a proper study of infants.

What is known, however, is that tummy time is important for infants' development. By spending time on their stomachs, babies develop muscles that they need to roll, sit and crawl. Tummy time also helps prevent tight neck muscles and the development of flat areas on the back of the head. When babies don't get enough tummy time, they may miss physical milestones and need therapy to catch up.

What you need to know. Although the connection between infant seats and tummy time still needs study, the takeaway message here is clear: make sure your baby gets regular time on his or her stomach throughout the day. How much is best? Ideally, according to the APTA, babies should be placed on their tummies after every nap, diaper change and feeding, for at least one to two minutes. And besides being good for your baby, tummy time provides an excellent excuse to get down on the floor and play, which can be a treat for you as well as your little one.

—Sophie Ramsey, patient editor, BMJ Group

ConsumerReportsHealth.org has partnered with The BMJ Group to monitor the latest medical research and assess the evidence to help you decide which news you should use.

Read what our Babies & Kids bloggers have to say about tummy time and ways to ensure your baby gets enough of it, and find out more about toys that can aid in your child's development.