Parents sometimes worry that if their baby seems overly irritable, that could be an omen of distress later in life, too.

So the new findings should help set their minds at ease, said lead researcher Dr. Rebecca Hyde, of Mater Children's Hospital in South Brisbane, Australia.

The study found that when moms said their baby cried excessively and had other problems "settling," they were also more likely than other moms to report behavior problems once their child was a teenager.

Yet those "problem children" did not see themselves that way. And by the time they were 21 years old, their mental health was on par with that of their peers.

There could be a number of things going on to explain the findings, Hyde told Reuters Health in an email.

"It may be that the child's early behavioral dysregulation has affected the relationship between the child and the mother, such that the mother continues to see the child as having problems, even when they do not," she explained.

Hyde said it's also possible that, for whatever reason, some moms are always going to see more problems in their kids than other mothers.

The findings, which appear in the journal Pediatrics, are based on nearly 3,100 young adults who were born in the early 1980s and followed to the age of 21.

When they were six months old, their mothers answered questions about how often their baby had feeding problems, sleeplessness or colic or was overactive.

There's no hard definition of "colic." But Hyde said it is generally based on the "rule of threes": babies who cry or are unsettled for more than three hours per day, on more than three days per week, for longer than three weeks are considered colicky.

In this study, the 10 percent of infants with the most distress were more likely to have behavior issues later in life - based on their moms' perceptions.

Those mothers were between 60 percent and over twice as likely to say their children had problems like aggression, depression and withdrawal when they were five and 14 years old.

But when kids were surveyed about their own behavior and mental well-being at age 14, the formerly colicky babies reported no more issues than their peers.

What's more, they showed no more signs of trouble when their behavior and mental health were evaluated at age 21.

According to Hyde, some parents worry that their anxious, distressed baby will grow up to be an anxious, distressed adult.

"I would say that parents should be reassured that their children are not going to have long-term behavioral or mental health concerns," Hyde said.

If your baby does seem colicky, she noted, it's important to remember that the phase will end, and to try to keep a "positive relationship" with your child. That, according to Hyde, may take some help from family and friends.

It's not clear why mothers of fussy babies reported more behavior problems later in life, even when their kids did not.

Moms were screened for anxiety and depression around the time they gave birth. And that, along with education and income, seemed to partly explain the findings - but did not fully account for them.

"There may be other factors involved in this that we did not measure in this study," Hyde said.

For now, she and her colleagues suggest that pediatricians try to support and reassure parents who believe their baby is colicky.

SOURCE: bit.ly/Rc9cv5 Pediatrics, online October 1, 2012.

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