To let them cry or not to let them cry? That is the question.

Babies and sleep are two great things that often just don't go together. Many a parent has had to figure out a method for sneaking in shut-eye in the months (or even years) after their baby's birth. I can tell you from experience, two times around, that there is no one quick and easy solution to getting babies to sleep through the night.

Some parents co-sleep, allowing baby to share their beds and thus minimize cries throughout the night. Others place baby in a crib, but rise to address needs whenever the baby cries. And some folks opt for the "cry it out" method which supposedly teaches babies to "self-soothe" by allowing their cries to go unanswered.

It is the latter method that was recently the subject of a new study published in the journal Pediatrics, which found no lasting effects on either a child's behavior nor the parent-child relationship. In other words, letting your baby cry at night won't do any damage in the long run.

Australian researchers worked with nearly 50 infants whose parents described them as having sleep problems, and they divided the babies into three groups. As Claire McCarthy, MD, reports for Harvard Health:

One was told to do “graduated extinction,” during which they let the baby cry first just for a minute before going in and interacting with them, and then gradually increased the amount of time they let them cry. Another group did something called “bedtime fading,” where they told the parents to delay bedtime so that the babies were more tired. The last group was the “control” group and got education on babies and sleep, but nothing else.

To determine the effect each sleep method had on babies, researchers measured the level of cortisol (a stress hormone) in their saliva. Here's what they found: Infants in the "graduated extinction" and "bedtime fading" groups fell asleep faster and had less stress than the control group. Plus, their mothers were less stressed. As far as emotional or behavioral problems, all three groups were the same.

A 2012 study also published in the journal Pediatrics had similar findings. Australian researchers followed 225 children from infancy through age 6 to track whether a behavioral sleep program had long-lasting effects on children’s mental health. They were divided into two groups: One group used sleep-training techniques and the other was a control group. According to the American Academy of Pediatrics (AAP), by age 6 "children who had been offered the sleep program as babies were similar to the control group in their mental and behavioral health, sleep quality, stress and relationship with their parents. The same applied to mothers’ mental health and parenting style. The authors conclude that the sleep techniques are cost-effective and safe to use. Parents and health professionals can feel confident using behavioral techniques for managing infant sleep."

Speaking of stress

Crying baby in crib Every parent needs to figure out what will work best for their family, with their children, their sleeping styles, and their family's needs. (Photo: Lopolo/Shutterstock)

These findings are completely opposite of those in a 2011 study published in Psychology Today in Psychology Today, which stated that letting children cry it out can be dangerous, leading to a lifetime of irreversible harm. A bit dramatic don't you think?

While I don't completely disagree with the premise that letting babies cry it out is stressful for babies, I have to question the authors' theories when they pepper their report with tidbits like this one:

"A crying baby in our ancestral environment would have signaled predators to tasty morsels," writes Darcia Narvaez, an associate professor of Psychology and director of the Collaborative for Ethical Education at the University of Notre Dame. "So our evolved parenting practices alleviated baby distress and precluded crying except in emergencies."

So babies only cry when there is an emergency? HA! Tell that to the millions of parents rocking colicky babies that just cry — all day long — for no discernible medical, environmental or emotional reason. I'm not saying that colicky babies aren't distressed, but is their crying really an emergency?

According to the 2011 study, a stressed baby releases cortisol, which can damage or even destroy neurons in their still-developing brains. And according to the researchers, this damage can later lead to a higher incidence of ADHD, poor academic performance and anti-social tendencies.

I can see how flooding the brain with cortisol could lead to developmental damage, but it's not clear to me that the researchers are distinguishing between "neglect" or never answering you baby's cries, and "crying it out," whereby babies are allowed to cry one or two times throughout the night.

The study states:

"In studies of rats with high or low nurturing mothers, there is a critical period for turning on genes that control anxiety for the rest of life. If in the first 10 days of life you have low nurturing rat mother (the equivalent of the first 6 months of life in a human), the gene never gets turned on and the rat is anxious towards new situations for the rest of its life, unless drugs are administered to alleviate the anxiety."

So parents who opt to let babies cry it out are automatically considered low-nurturing? Seems a bit harsh for the millions of parents who care for their baby all day long but let them cry a few times at night in between feedings and diaper changes.

And when Narvaez suggests that parents turn to the cry-it-out method because it is "easier" and fits their needs instead of their babies, I have to wonder if she has ever even been in the presence of a real baby at nighttime. When a baby has difficulty sleeping, there is NO EASY METHOD for parents who are trying to sleep. A crying baby is an awful thing to listen to, and it certainly doesn't make it easier for parents to get their shut-eye. I did not do it with either of my girls primarily because it would have stressed me out as much as if not even more than it did them. But I think every parent needs to figure out what will work best for their family, with their children, their sleeping styles, and their family's needs.

What do you think? Did you let your baby cry it out at night?

Editor's note: This story has been updated since it was originally published in December 2011.