STATE COLLEGE, Pa. — While sleeping in the same bedroom as your baby is touted by the American Academy of Pediatrics (AAP) as a smart practice for the entirety of an infant’s first year of life, a new study finds there some major downsides to parent-child room cohabitation beyond four months.

Researchers at Penn State examined data collected from a previous study, which included 279 mothers who had given birth at Milton S. Hershey Medical Center, along with their babies.

Baby sleeping
A new study finds that room-sharing with a baby beyond four months can be detrimental to the infant’s sleeping habits, raising health risks.

Hoping to find the optimal age for infants to sleep on their own, the researchers administered a questionnaire to mothers at two distinct points: when their child was four and nine months old. The survey assessed sleep duration, location, night walking, night feedings, bedtime routines, and sleep behaviors.

Certain variables — sleep duration, location, and sleep patterns — were again examined at 12 and 30 months of age.

The researchers found that at four months of age, babies who slept in their own room at night enjoyed 45 minutes of additional continuous sleep than those who slept with their parents.

By nine months, this disparity had more than doubled to an hour and 40 minutes.

In addition, the total amount of sleep, interrupted or uninterrupted, was also found to be longer on average for babies who slept in their own bedroom.

“Inadequate infant sleep can lead to obesity, poor sleep later in life and can negatively affect parents,” says study author  Dr. Ian Paul, professor of pediatrics, in a university news release. “Many pediatricians and sleep experts question the room-sharing recommendation until one year because infants begin to experience separation anxiety in the second half of the first year, making it problematic to change sleep locations at that stage. Waiting too long can have negative effects on sleep quality for both parents and infants in both the short and long term.”

Many parents argue that the potential for their child to fall victim to sudden infant death syndrome (SIDS) is a good reason to keep a baby close by, but the researchers explain that the vast majority of SIDS cases — 90 percent — occur before a child is six months of age. While the AAP says it’s ideal for a baby to sleep in the same room as its parents for its first 12 months, it suggests the practice last at least six months.

“Our findings showing poorer sleep-related outcomes and more unsafe sleep practices for babies who room-share beyond early infancy suggest that the American Academy of Pediatrics should reconsider and revise the recommendation pending evidence to support it,” says Paul.

Separation anxiety and the increased hazard associated with sleeping in a parent’s bedroom, not to mention poor sleep on the part of parents, are additional reasons for sleeping in separate quarters past four months, the researchers argue.

But Paul says another negative consequence stands out as a reason to avoid room-sharing beyond four months: the increased likelihood that the baby will wind up sleeping in the same bed as its parents.

“Perhaps our most troubling finding was that room-sharing was associated with overnight transitions to bed-sharing, which is strongly discouraged by the American Academy of Pediatrics,” he says. “Bed-sharing overnight was more common in our sample among 4- and 9-month-olds who began the night on a separate surface in their parents’ room.”

The study’s main flaw is perhaps its lack of diversity: it mostly examined white families who weren’t of a low socioeconomic status. A subsequent study could perhaps be replicated amongst other demographics.

The study’s findings were published in the journal Pediatrics.

About Daniel Steingold

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  1. Christina Kuhn says:

    I moved my kids out at 3 weeks old for the very reason — they were becoming more aware and waking up at night more. As soon as I moved them out into their own bedrooms, they slept SIGNIFICANTLY better and so did my husband and I. I know this arrangement may not work for every family, but I’m so glad to see a study pointing this out instead of what the AAP says. If I had waited until my son was 6 months old, he would have had a much harder time, and waiting until a year? I don’t think he would have ever been able to sleep well or sleep alone!