Chinese women are also among the most ambitious on earth, according to a study from the Center for Work-Life Policy in New York, which found 76 percent of women in China aspired to top jobs, compared with 52 percent in the US.

Nandani Lynton, of the China-Europe International Business School in Shanghai, identified political and social factors for making a scrap paper lady from China richer than the doyennes of Zara, Gap, Benetton and Ebay.

"Mao made an incredible difference when he said women hold up half the sky. Since then it has been assumed that all women in China will work." said Ms Lynton.

The world's three richest women are Chinese -- as are 11 of the top 20, showed the Hurun List of Self-Made Women Billionaires published on Thursday.

Working mothers in China and other Bric countries "are able to aim high, in part because they have more shoulders to lean on than their American and European peers when it comes to childcare", the center noted.

Nandani Lynton noted that it was not just the availability of cheap or free childcare but also the absence of any stigma attached to using it that helped Chinese women dominate the global rich lists.

With an average work week of 71 hours for Chinese women, cheap childcare is essential, and in China is often provided by grandparents -- four for every only child.