A study of more than 12,000 children over the past decade may not bring good news for parents with full-time jobs
The quality of childcare matters
The study, which followed children born in 1991 and 1992, discovered by and large that having a working mum does not affect a child's development.
But - there are two exceptions to that finding.
Children whose mothers return to full-time work before they're 18 months old tend to do slightly worse than their peers, according to researchers from Bristol University.
But - surprisingly - they discovered much worse effects on children's development if they're looked after in the long term solely by unpaid friends, neighbours or relatives.
The news will come as a disappointment to many low-paid women, who cannot afford the cost of formal childcare such as nursery places or child-minders.
Until now, getting a relative to help out has seemed an ideal solution for many, who might not be able to hold down a job without such help
On Breakfast we spoke to the author of the report, Paul Gregg. To see that interview click on the link at the top of the page.
Paul Gregg is part of the team from Bristol University which assessed the development of more than 12,000 children born between 1991 and 1992.
Paul Gregg stressed that the overall message was one of ressaurance for working mothers - that going out to work does not, generally, damage children's performance at school.
But he explained that for children who do not receive diverse stimulation and are in unpaid care all week where the carer does not have the resources to provide stimulating care, then children could suffer.
In those cases, the study found a reduction in literacy and numeracy results of between 1 - 1.5% at the age of 5.
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