Children of mothers who worked full time during most of the pre-school years do less well at A-level and are more at risk of unemployment and psychological stress, according to controversial research published today by the Joseph Rowntree Foundation. Academics at Essex University followed the fortunes of 1,263 young people born in the 1970s to investigate links between the parents' patterns of work and the children's subsequent wellbeing.
They found there was a trade-off for mothers spending less time with children under five because of full-time work commitments. The advantages of raising family income were offset by the risks of reducing their children's long-term attainment at school.
The study, by John Ermisch and Marco Francesconi of the university's institute for social and economic research, did not identify such clear disadvantages if fathers worked full time or mothers worked part time.
Professor Ermisch, an academic whose previous work included explosion of the myth that young women became pregnant to jump the housing queue, said the findings supported the need for progressive employment policies. "Entitling parents to more time with young children can be justified as a potential investment in the labour force of tomorrow," he said.
Unlike previous research, the Essex project looked at pairs of brothers and sisters whose only detectable difference was the amount of time spent by their parents at work.
Children of mothers who worked full time for about 18 months during the pre-school years had a 64% chance of passing an A-level. The odds fell to 52% if the mother worked full time for an additional year.
Longer periods of full-time working increased the probability of unemployment when the child reached adulthood from 7% to 9%. The chances of psychological stress also rose from 23% to 28%. But the probability of daughters giving birth before their 21st birthday reduced from 3% to 1%.
If mothers worked part time for long periods, their children were 6% less likely to get an A-level but they were 2% less likely to suffer mental problems later in life.
Since most fathers of children born in the 1970s were in full-time work during most of their children's upbringing, it was harder to measure the consequences. But if fathers spent longer at work when their children were very young, it was likely to lead to a 6% reduction in the A-level pass rate. The children of those fathers were less likely to be unemployed or suffer psychological stress.
Prof Ermisch said: "The young people in our study were pre-schoolers more than 20 years ago when working parents may have had fewer options in terms of alternative childcare.
"Even so, the implication of our findings is that if parents have less time to spend with young children before they start school, there may be long term consequences.
Mary MacLeod, chief executive of the National Family and Parenting Institute, said: "This is a comprehensive study that reinforces the need for parents of young children to have as much choice and flexibility as possible in balancing work and parenthood."
The government should build on last week's budget announcement of two weeks' paid paternity leave for fathers and increased maternity pay.
"We need to be cautious about making cast iron judgments on working mothers from one study ... For many mothers full-time work is a necessity, not a lifestyle choice. I hope this research won't be used as another stick to beat them," said Ms MacLeod.
Sue Monk, chief executive of the campaigning group Parents at Work, said the Essex study did not look at the quality of childcare provided when parents were at work. American research showed that good childcare improved children's later academic performance.
David Willetts, the shadow social security secretary, said the study showed the government was wrong to bias the tax and benefits system in favour of two-earner couples and institutionalised childcare. "Parents with young children should be free to choose whether and when they return to work," he said.
Research yields conflicting advice
Today's report from Essex University may perplex mothers who were reassured by previous studies:
• In 1999 Elizabeth Harvey of the University of Connecticut found no long-term difference between children whose mothers worked full time in their first three years and those whose mothers did not. Early differences in obedience and academic achievement did not persist.
• A Canadian study in 1998 found the money earned by working mothers was good for children because it improved living standards.
• Last year Heather Joshi and Georgia Verropoulou of London University's institute of education found a slight risk children read less well if mothers worked while they were under five - and were 10% less likely to do A-levels. But poverty, family history and mother's education were bigger influences.
• Research last year by Bristol University found half of mothers returning full time switched to part time within two years, and 19% gave up work completely.
• Preliminary findings from Kent University show only 60% of mothers intending to return full time did so by the time babies were six months; the trend was to do less work than intended.
