Why babies need more tummy time than they're getting.

What women really think about news, politics, and culture.
Dec. 2 2010 2:29 PM

Tummy Time

Why babies need more of it than they're getting.

Don't be afraid to put babies on their tummies when they're awake. Click image to expand.
Don't be afraid to put babies on their tummies when they're awake

In the early 1940s, Dr. Harold Abramson, a New York pediatrician, pored over heartrending reports of babies who accidentally suffocated while they slept. As he reviewed case after case, he noticed that a vast majority of the deaths occurred when babies slept on their stomachs. In a commentary in the Journal of Pediatrics, Abramson suggested that the many case reports of infant suffocation hinted that a newborn's sleeping position might contribute to so-called "crib death," later called SIDS. In the following decades, other researchers noticed that SIDS was less common in countries where infants typically slept on their backs. Fifty years after Abramson's study, the American Academy of Pediatrics formally launched a "Back to Sleep" campaign, instructing parents to put babies to sleep on their backs during their first year. The campaign has been hugely successful: Since it started in 1992, the SIDS rate in the United States has been cut in half.

There's a drawback, however: Telling parents not to put babies to sleep on their stomachs has scared them away from placing babies on their bellies altogether. And taking away "tummy time," it turns out, cuts off a pivotal avenue of development. The less time infants spend on their stomachs, the slower they generally are to acquire motor skills during their first year, which means the potential delay of simple feats like lifting their heads as well as more-complicated movements like rolling over, crawling, and pulling to stand. Doctors have hesitated to sound the alarm about this, since children usually walk shortly after their first birthday regardless of how much tummy time they've had. But a growing body of evidence now suggests that the timing of the motor-skill milestones that precede walking is crucial and can even factor into long-term health and cognitive ability.

Four years after the Back to Sleep campaign launched, its inadvertent effects started trickling into the clinic. Most notably, some infants had disfiguring flat spots on the back soft crowns of their heads. It took a few years for researchers and doctors to realize that the change in sleeping position also affected prewalking motor skills (whether or not a baby had a misshaped head). Then in 2004, a research team led by Bradley Thach at the Washington University School of Medicine studied the difference in head movements between stomach and back sleepers. Thach showed that babies who spent nights on their bellies quickly developed the brain connections and muscle strength to turn their heads from side to side—one of the first motor-skill hurdles. Babies who consistently slept on their backs, on the other hand, were less likely to have sufficient head mobility at 3 to 5 months.

Advertisement

Next a research group at McGill University, directed by Annette Majnemer, weighed in on the effect of sleeping position on development at six months. They found continuing motor setbacks. A larger fraction of the back sleepers than the tummy sleepers couldn't roll over, touch their toes, or sit upright with arm support.

Pediatricians have had mixed reactions to these clinical observations. Some have passed off the flat heads as a passing cosmetic issue and the lag in prewalking motor-skill development as inconsequential. Others, including the American Academy of Pediatrics, champion of the Back to Sleep campaign, have seen the head shapes and motor hang-ups as a harbinger of future problems and recommended supervised tummy time when a baby is awake.

TODAY IN SLATE

Politics

Talking White

Black people’s disdain for “proper English” and academic achievement is a myth.

Hong Kong’s Protesters Are Ridiculously Polite. That’s What Scares Beijing So Much.

The One Fact About Ebola That Should Calm You: It Spreads Slowly

Operation Backbone

How White Boy Rick, a legendary Detroit cocaine dealer, helped the FBI uncover brazen police corruption.

A Jaw-Dropping Political Ad Aimed at Young Women, Apparently

The XX Factor
Oct. 1 2014 4:05 PM Today in GOP Outreach to Women: You Broads Like Wedding Dresses, Right?
Music

How Even an Old Hipster Can Age Gracefully

On their new albums, Leonard Cohen, Robert Plant, and Loudon Wainwright III show three ways.

How Tattoo Parlors Became the Barber Shops of Hipster Neighborhoods

This Gargantuan Wind Farm in Wyoming Would Be the Hoover Dam of the 21st Century

Moneybox
Oct. 1 2014 8:34 AM This Gargantuan Wind Farm in Wyoming Would Be the Hoover Dam of the 21st Century To undertake a massively ambitious energy project, you don’t need the government anymore.
  News & Politics
Politics
Oct. 1 2014 7:26 PM Talking White Black people’s disdain for “proper English” and academic achievement is a myth.
  Business
Moneybox
Oct. 2 2014 8:07 AM The Dark Side of Techtopia
  Life
Quora
Oct. 2 2014 8:27 AM How Do Teachers Kill the Joy of Reading for Students?
  Double X
The XX Factor
Oct. 1 2014 5:11 PM Celebrity Feminist Identification Has Reached Peak Meaninglessness
  Slate Plus
Behind the Scenes
Oct. 1 2014 3:24 PM Revelry (and Business) at Mohonk Photos and highlights from Slate’s annual retreat.
  Arts
Brow Beat
Oct. 2 2014 8:47 AM Season 2 of The Bridge Was Confusing, Bizarre, and Uneven. I Loved It.
  Technology
Future Tense
Oct. 1 2014 6:59 PM EU’s Next Digital Commissioner Thinks Keeping Nude Celeb Photos in the Cloud Is “Stupid”
  Health & Science
Bad Astronomy
Oct. 2 2014 7:30 AM What Put the Man in the Moon in the Moon?
  Sports
Sports Nut
Oct. 1 2014 5:19 PM Bunt-a-Palooza! How bad was the Kansas City Royals’ bunt-all-the-time strategy in the American League wild-card game?