Researchers at the University of Iowa found that the more time fussy, irritable infants spend in day care, the less likely they are to develop a secure attachment with their mothers.
A secure attachment means babies are at ease exploring their surroundings, but can still seek comfort from their mom when they need to. The findings also mean irritable infants do better when they're mostly cared for by their parents or other family members.
"People have always thought of irritable, difficult babies as being more likely to have poor outcomes if they have stresses," said study researcher Beth Troutman, a professor of psychiatry at the University of Iowa.
"But the other side of that is that they're more likely to have good outcomes if they have more positive supportive environments," Troutman told LiveScience.
"So it's not just that having them in day care is a risk, but also that irritable babies really benefit from spending time with family members." For the study, Troutman's team assessed 48 one-month-old infants for their level of irritability between 1999 and 2002.
During the first year of the babies' lives, mothers were interviewed at four follow-up visits and asked who had taken care of the infant over the past week and for how long.
When the babies were a year old, they were videotaped interacting with their mothers to determine whether they were securely or insecurely attached. A roughly equal number of irritable and non-irritable infants were seen as insecurely attached.
It was found that irritable infants were more likely to develop an insecure attachment if they spent more time in day care rather than with family. There was no such link for the non-irritable infants.
It's possible that irritable infants are more sensitive to their surroundings than non-irritable infants. So when the fussy babies spend time in day care, where caregivers may not be able to attend to every cry, they are more prone to negative consequences, said Troutman.
"In a day care setting, it's hard to respond to six babies, and the irritable crying baby might not get as much attention or support in day care," she added. However, Troutman cautioned against drawing general advice from the findings which are based on just one study of small group of infants. But if parents have the resources available, she recommended irritable infants spend more time at home with family rather than in day care.
The study was presented at the American Academy of Child and Adolescent Psychiatry's Annual Meeting.
