Where Moms Work the Hardest

"Working mothers have become the biggest issue in most countries," said Shelley Correll, an associate professor of sociology at Stanford University. "European countries have taken aggressive steps to increase the number of mothers participating in the workforce, because they feel it is in their interests to keep them fully engaged in the labor force."

These policies have proved extremely effective in many countries. In Iceland, mothers are more likely to work than women without children. Nearly 90% of all mothers in Iceland are employed, which makes it the country with the largest share of moonlighting mothers.

Iceland is not the only country where mothers are more likely to be employed than women without children; in at least six other countries, moms are more likely to be employed than non-moms--at least for mothers with only a single child. In Portugal, mothers with more than one child are more likely to be part of the workforce than women with no children.

Market-Driven

For better or for worse, the countries with the highest rates of employed mothers do not necessarily have the most family-friendly policies. Iceland offers just three months of partially paid maternity leave, a far less generous policy than other countries. On the other hand, Iceland has had one of the lowest unemployment rates and tightest labor markets in the world in recent years.

The bottom line: Labor markets are the ultimate arbiters of gender equality in the workforce. This certainly seems to be true in the U.S.

"During World War II, women needed to work, because there weren't enough men to work in the factories," says Correll. "The government began multiple initiatives designed to get more women into the work force--and it worked. When the war ended, so did many of the initiatives. But there is no question that if U.S. productivity hinged on retaining mothers in the workforce, these policies would be put back into place on a dime."

In the absence of tight labor markets, mothers must claw their way into the workforce if they want to compete. This is no mean feat. In a study published last year, Correll found employers tended to view mothers as less competent and committed than other workers, held them to higher standards and offered them lower salaries. The bias against mothers did not necessarily extend to women generally; employers call back mothers half as often as women without children.