The global economy's recovery has been anemic at best, but putting women to work would likely change that, the world's lender of last resort said.
"Increasing women's economic participation can, in turn, lead to higher growth," Christine Lagarde, managing director of the International Monetary Fund (IMF), said in a blog post Monday.
She cited data showing that increasing women's labor force participation to equal men's would boost gross domestic product (GDP) by 5 percent in the U.S., 9 percent in Japan, 12 percent in the U.A.E. and 34 percent in Egypt.
Conspiracy
But there are serious headwinds -- what Lagarde called an "insidious conspiracy" -- to getting more women in the workforce.
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"Almost 90 percent of countries have at least one important restriction in the books, and some have many," she noted, citing obstacles including requiring a husband's permission to work and barring women from some professions.
It's an issue that got some extra time in the spotlight this week, when actress Patricia Arquette used her acceptance speech for the Oscar award for Best Supporting Actress to advocate for equal pay.
"It's our time to have wage equality once and for all and equal rights for women in the United States of America," Arquette said.
Big impact
Clearing away restrictions can have a huge impact on women's economic contributions.
"Less legal discrimination against women is strongly associated with higher female labor force participation," according to an IMF study published this month.
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In 50 percent of countries where equity was legally granted, women's labor force participation rose by around 5 percentage points in the following five years, the study found.
In the wake of moves to abolish "customary law" and equalize the legal treatment of women in Namibia and Peru in the 1990s, both countries saw their female labor participation rates climb 10-15 percentage points over the following decade, the report said.
"Restrictions on women's rights to inheritance and property, as well as legal impediments to undertaking economic activities such as opening a bank account or freely pursuing a profession, are strongly associated with larger gender gaps in labor force participation," the study said.
"Gender gaps in entrepreneurship and labor force participation significantly reduce per capita income," it said. "Constitutionally guaranteed equity between men and women should be the absolute minimum."
—By CNBC.Com's Leslie Shaffer; Follow her on Twitter @LeslieShaffer1