Now, a new study released today in the journal Pediatrics suggests it is OK to let babies cry while trying to fall asleep -- a finding that may help settle a long-running debate among both parents and experts over whether allowing a baby to cry itself to sleep harms the child in the long run.
Australian researchers looked at 225 babies from seven months to 6 years of age to compare the difference between parents who were trained in sleep intervention techniques and those who were not. Specifically, researchers allowed parents in the sleep intervention group to choose one of two sleep training techniques to use with their baby. Parents who chose "controlled crying" responded to their infant's cry at increasing time intervals. Parents who chose "camping out," also called "adult fading," sat with their infant until they fell asleep, removing themselves earlier each night over three weeks.
Parents in the control group were not taught the sleep training techniques and instead provided their own routine care.
What the researchers found was that children and mothers in the sleep training group had improved sleep, and the mothers were less likely to experience depression and other emotional problems. These benefits lasted up to the time the babies turned 2.
Moreover, the study looked at various factors to determine whether harm was done to children in the sleep training group, including mental and behavioral health, sleep quality, stress, and relationship with their parents. They found no differences between children in the two groups, leading researchers to conclude that these sleep training techniques are safe to use.
"Parents can feel confident using, and health professionals can feel confident offering, behavioral techniques such as controlled comforting and camping out for managing infant sleep," the researchers write in the study.
Experts not involved with the study said the findings make sense.
"It's kind of like having the ability to get a rental car at the airport, but why would you get one if a limo shows up?" said Dr. Ari Brown, an Austin, Texas-based pediatrician and author of Baby 411. "The parent is the limo."
"While stressful for the infant, it almost certainly falls under the 'positive stress' heading," said Rahil D. Briggs, director of the Healthy Steps program at Montefiore Medical Center in New York. "Positive stress creates growth in the child, in the form of coping skills and frustration tolerance that serve to be critically important throughout the life span."
But for parents, the message may be even more important.
"This study empowers parents to be active in shaping their infant's behavior to be consistent with appropriate developmental milestones," said Dr. John Walkup, director of child and adolescent psychiatry at NY-Presbyterian/Weill Cornell Medical Center.
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