The government's Women and Work Commission claims that discrimination and lesser opportunity for women are deeply ingrained in our society." But is it? Or is the Commission missing the point?
The Women and Work Commission was set up by the government in September 2004 with a mandate to "close the gender pay and opportunities gap within a generation."
And in its interim report published this week it acknowledges that "some women are succeeding, in well-respected and well-paid careers, and are managing to combine work and family life, difficult though it may be at times."
But it adds that "others find it difficult to enter work, perhaps because of their caring responsibilities or through facing multiple discrimination."
"Discrimination and lesser opportunity for women are deeply ingrained in our society," it claims, pointing to the fact that women earn 18.4 per cent less on average than men as evidence for widespread discrimination.
But according to research published this month by Satoshi Kanazawa of the London School of Economics, pay and career differences between men and women are a matter of biological fact, not discrimination.
"Economists usually assume that any sex difference in earnings after controlling for human capital and occupational segregation is largely (though not entirely) attributable to 'discrimination'" Kanazawa writes in this month's edition of the Journal of Economic Psychology.
"From the evolutionary psychological perspective, I argue that "discrimination" (or any other external constraint) is unnecessary to explain the partial effect of sex on earnings if men and women are inherently different in their desire to earn money.
From this perspective, reproductive success (rather than earnings) is the ultimate (albeit unconscious) goal of all biological organisms, including humans, and earnings are men's, but not women's, means to reproductive success."
Kanazawa's research, based on surveys of the attitudes of more than 18,000 men and women on their attitudes to work over a 25-year period, found that amongst women, unmarried and childless women aged under 40, the difference in earnings with men disappears.
In other words, as he goes on to say, women with children choose different types of jobs than men because they have better things to do than making money.
"The General Social Survey data are consistent with my contention that evolved (not learned) differences in preferences are largely responsible for sex differences in pay, and confirm my prediction that there is no sex gap in earnings among childless unmarried workers under 40," Kanazawa asserts.
"My conclusion is that the sex gap in pay exists because women have better things to do than to earn money, reproductively speaking."
And it seems that many women would agree. In the UK, some two-thirds of mothers say they would rather quit their jobs and stay at home with their children - if they could afford it.
Kanazawa's theory is also borne out by pay statistics that compare like-for-like remuneration rather than just average earnings.
For example, according to the 2003 National Management Salary Survey, not only has the proportion of women in management posts has more than trebled in the last ten years, but women managers are also paid the same as their male colleagues.
The salary of the average female department head was less than 1 per cent lower than that of the average male equivalent (equating to a difference of £475), while in the most senior management positions the difference was smaller still.
Nevertheless, a significant like-for-like gap was revealed in certain job roles, particularly among company financial managers and treasurers, where women's average hourly earnings are only some 60 per cent those of men's.
The Salary Survey also found that women's pay rises had outstripped men's for the seventh year running, with an average rise of 5.9 per cent compared to only 5 per cent for men.
In contrast, the oft-cited gender gap in average earnings is distorted by a very small number of extremely high earning men. In 2003, the pay for the top 5 per cent of male employees grew at such a rate that it pulled the average for all men upwards and further away from the average for all women.
But in the remaining 95 per cent of the workforce, women's average hourly earnings grew at a faster rate than men's.
Meanwhile, as the Women and Work Commission acknowledges: "some women will always choose to take significant time out of the labour market and that this will have implications for the gender pay gap or their earnings over their lifetime."
It also has implications for career trajectories. As the National Management Salary Survey showed, female managers are far more likely to resign than their male counterparts.
The growing phenomenon of high-flying women choosing to leave the workplace has recently been termed "the hidden brain drain", with research in the USA finding that of the 1981 class at Stanford University, 57 per cent of women graduates have left the workforce while of three graduating classes from Harvard Business School, only 38 per cent of women are still in full-time careers.
The same trend is reflected in the UK, where, as the Women and Work Commission points out, only 32 per cent of managers and senior officials are women.
But as research published in the March issue of the Harvard Business Review found, 44 per cent of professional America women who exit the workforce do so to gain more family time.
But while more than nine out of 10 want to return to work, only three-quarters find jobs and only four out of 10 return to full-time employment
Tellingly, however, not one woman surveyed who had left a job in business, banking or finance to have children wanted to return to their old companies.
So although many women simply choose less demanding, less well-paid jobs after having children, many others want to return to their careers but are being sidelined by the rigidity of career paths and the unforgiving nature of most corporate cultures.
Other evidence that corporate culture needs to change comes from research carried out last year at the University of Exeter which found that women who do make it to the top of organisations are more likely than men to find themselves on a 'glass cliff', meaning their positions are risky or precarious.
Professor Alex Haslam and Dr Michelle Ryan found that women who break through the glass ceiling often find themselves in hopeless positions because the tasks they are confronted with are impossible.
"It seems that if the company is in crisis, then managers always turn to women as a kind of last resort. Male managers seem to think women are better at dealing with a crisis," Professor Haslam said.
"This is just the latest example of discrimination in the workplace. Although women are beginning to break through the glass ceiling, there is this new wave of subtle sexism. Women are getting these jobs, but it is a real poisoned chalice. It is definitely more of a glass cliff."