Although women have earned their place at the office for decades, an equal partnership still often eludes them at home — couples often prioritize the careers of husbands over those of wives, researchers find.

Cornell sociologist Youngjoo Cha investigated 8,484 professional workers and 17,648 non-professional workersthose not requiring advanced education or trainingdual-earner families using data collected by the U.S. Census Bureau from 1995 to 2000. Her analysis showed that having a husband who works 50 hours or more per week could hurt a woman's career.

Overall, having a husband who worked 60 hours or more per week increased a woman's odds of quitting her job by 42 percent. However, for husbands, having a wife who worked 60-plus hours a week did not significantly affect a man's odds of quitting. (The researcher excluded workers who quit due to layoffs, illness, disability or lack of interest in working to prevent the possibility that employment decisions were involuntary or due to low commitment to work.)

"This effect is magnified among workers in professional and managerial occupations, where the norm of overwork and the culture of intensive parenting tend to be strongest," Cha said.

Indeed, the odds of quitting increased by 51 percent for professional women whose husbands worked 60 hours or more per week. For professional mothers, the odds they would quit their jobs were more than twice greater than those of professional mothers whose husbands worked less than 50 hours per week. In comparison, for professional men, both parents and non-parents, the effects of a wife working long hours were negligible.

Work-family balance

The results don't suggest men are solely to blame, the researchers say, but rather the gender roles that men and women expect, as well as the nature of the workplace.

Women have less time available to do paid work, because they are still expected to do more housework and perform most of the care-giving responsibilities, an idea supported by how mothers seemingly are especially placed under pressure, Cha noted. As such, hard-working women are put at a distinct disadvantage to their male peers.

"It's not just about men expecting women to quit, it's women too — women feel more guilty when they can't spend a lot of time with their families," Cha told LiveScience. "For instance, when children get sick, prior research shows women are more likely to miss work for urgent childcare then compared to men. When such critical moments come, the expectations work that way."

Working long hours is increasingly common in the United States. Past studies found that from 1970 to 1990, on average the number of hours that people were paid to work per year in the nation increased by 163, or roughly three extra hours per week. In higher-paying professional jobs, overwork is more common and expected.

"The findings suggest that the prevalence of overwork may lead many dual-earner couples to return to a 'separate spheres' arrangement — breadwinning men and homemaking women," she said.

Modern times

The current worldwide economic recession might influence this gender inequality, Cha noted.

"The data I analyzed from 1995 to 2000 was during a boom period, so I'm guessing this effect is more prominent in boom times," she explained. "During the 2001 economic recession, this gender effect was still there, but its magnitude was smaller."

Still, Cha noted other research suggested "that even when men are unemployed and work fewer hours, they don't necessarily contribute more to housework. They overcompensate for their masculinity — they tend to think if they're not financially providing support for the family, they feel insecure about their position, and they reaffirm their traditional roles."

Although there has been much recent talk about stay-at-home dads growing in number, "I think it's a very small percent of the population of those in the labor force, and won't have much influence on this effect," Cha added. "There is a lot of inertia in the workplace and with these gender norms."

Cha detailed her findings in the April issue of American Sociological Review.