A recent study has shown that the negative behavior, of children who spend long hours in the nursery at home, affects their classmates when they are at school.
Many studies have shown that the children with full-time nursery care are more likely to be aggressive and disobedient than their classmates.
The study led by Jay Belsky, the director of the Institute for the Study of Children, Families and Social Issues at Birkbeck University, London revealed that this negative behaviour may have an adverse effect on the behaviour of other classmates also.
"Being in a classroom with a high proportion of children who have extensive childcare histories affects those with little or no early childcare experience," Times Online quoted Belsky as saying.
"So if your child had no childcare, but ended up in a class where lots of children had childcare, your child ends up being more aggressive. There is a contagious effect," he added.
The researchers examined 3,400 five-year-old Americans enrolled in 282 kindergarten classes, equivalent to the class in Britain.
They interviewed children's parents and gave a questionnaire to the teachers to measure the frequency of aggressive behaviour including arguing, fighting, getting angry, acting impulsively and disturbing classroom activities in each child.
They also examined the overall score of academic achievement of children.
The findings revealed that that children placed in any childcare for longer hours at earlier ages, exhibited considerably more problematic behaviour.
Those who had spent long hours in nursery had better academic scores, although this effect wore off for children in nursery for more than 30 hours a week.
While there were lots of students with childcare experiences these effects spread to everyone in the class.
"If the only way to survive in class is to push and shove, then all the children will think, 'Let's push and shove, too,'" he said.
" It was also possible that teachers were less able to manage whole-class discipline when there was a high proportion of disobedient children in the class, he added.
However, Beverley Hughes, the Children's Minister said that it should not be believed that findings from the US would apply equally to Britain.
"Evidence from this country suggests that the impact on children of childcare is crucially dependent on quality and the length of time children spend in it," she said.
"We know that when childcare is of high quality and led by well-qualified staff and when children do not spend overly long in it, then the overall benefits are positive."