Gordon Brown has looked at the social mobility utopia that is Scandinavia and noticed one startling difference between them and us.

Childcare there is universal and heavily subsidised so that all children, rich or poor, share the same kindergartens once their mothers go back to work after a year or so of maternity leave.

And all mothers do go back to work. There is virtually no difference in employment rates between men and women in Denmark, for example, and it is considered bizarre to care for children full-time.

Many experts think that, instead of counting back from school age with nursery subsidies, Mr Brown should start at the other end and help women to stay in the labour market once they start a family.

The crippling cost of childcare in Britain means that mothers intending to go back to their old jobs after maternity leave for, say, three or four days a week, simply cannot afford it. Despite the huge increase in places over the past ten years, an average London nursery charges £200 a week. Two thirds of parents say that they struggle to afford childcare.

The highest-paid women can easily pay the bills and the children's tax credit helps the lowest-paid with nursery fees, but for the thousands of new mothers in the middle, this is the point when they decide to stay at home.

Under current rules, all children are entitled to 12.5 hours of free nursery care for 38 weeks of the year from the age of 3. That will rise to 15 hours by 2010. But, by the time that free provision kicks in, mothers are often expecting another baby, so there is no point trying to find a new job.

Once both children are in nursery or school, their mother has been out of the labour market for perhaps five years and has to take whatever low-paid school-hours job she can get.

Subsidising childcare earlier might be of more benefit to the family than topping up their reduced income with tax credits.

Times Recommends

• What makes the perfect mum?
• To keep me stress-free, no more awareness days, please
• What do lottery winners buy?