Despite decades of progress toward equality, women are still more likely to pick up a broom at home than men, according to a new review of 10 years of research on gender and housework.

Women's lot in the housework arena has improved since 1965, when married or cohabitating women did 30 hours of housework a week to a man's 4.9 hours. Estimates on time spent doing chores differ depending on how scientists define "housework," but one 2007 study in the journal Social Science Research found labor-saving devices and more help from men have slashed women's average housework burden to 13.2 hours per week. Multiple studies show, however, that women are still stuck with about two-thirds of the household labor.

Men's household contributions leveled off in the 1990s, according to the review published Dec. 3 in the journal Sex Roles. Researchers are unsure why the housework gap persists, despite increasingly egalitarian roles on the job. (According to the U.S. Department of Labor, women make up 46.8 percent of the U.S. workforce.) Other studies have shown that marriage boosts housework for women and cuts it for men. And even dual-earner families prioritize husbands' careers over wives', in part because of the demands of housework and gender-role expectations.

Many researchers have focused on individual characteristics to explain the housework gap, wrote the review's authors, psychologists Mylene Lachance-Grzela and Genevieve Bouchard of the University of Moncton in New Brunswick. Those characteristics include the amount of money each partner earns and the time each spends working outside the home, as well as their individual attitudes toward gender roles.

More recent studies have cast a wider net, investigating the relationship of national-level public policy with who takes the garbage out. Those studies find that in countries with more egalitarian gender roles (like Canada, Sweden and the United States), couples divide housework more evenly. In countries like Italy, Japan and Chile, where roles are more traditional, women do about twice the housework as women in egalitarian countries.

The results of individual policies are more inconsistent. Paid parental leave for men results in more chore-sharing, but state-supported daycare doesn't seem to ease women's housework burden, the review found. Social policies may be undermined by increasingly competitive workplaces, the authors wrote.

Either way, gender equality may be good for germ-phobes: In countries where gender roles are equal, the review found, even single men do more housework.

This article was reprinted with permission from LiveScience.

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