Mark Weinberger, chief executive of the international accounting firm Ernst and Young, recently announced his company would expand its paid family leave policy from 12 to 16 weeks. Don’t call it a perk for new moms, though.

“Women don’t want to be singled out,” Weinberger said at a panel discussion on paid leave this week in Washington, “and men don’t want to be left out.”

He touched on a stereotype that has long concerned gender equality advocates. Framing family leave as a “women’s issue,” they say, is not only inaccurate. The assumption fuels workplace discrimination against both genders: Mothers are seen as caretakers who prioritize home life, and fathers who take more than a week or two off are perceived as less serious about their careers.

Weinberger joins a growing roster of business leaders who explicitly support paternity leave — the kind that resembles traditional maternity leave. Last year, Facebook head Mark Zuckerberg announced he'd take two months off after the birth of his daughter. "Studies show that when working parents take time to be with their newborns, outcomes are better for the children and families," he wrote on Facebook.

But most American men take less than two weeks off to care for a new baby. That's partly because the United States guarantees no paid leave to new parents, and partly because it's less culturally acceptable for men to take advantage of an employer-supplied benefit. Fewer than 1 in 3 new dads use more than 10 days of leave, according to data from the Labor Department. Less than 1 in 7 receive pay for those days.

Economists say the parenting imbalance contributes to the gender wage gap and lack of women in top leadership positions. Men in the United States earn on average higher wages than their female counterparts and are promoted more often. A Third Way study this year found fatherhood is associated with a 6 percent wage boost for each child, while motherhood carried a 4 percent pay penalty.

“Fatherhood may serve as a signal to potential employers for greater maturity, commitment, or stability,” wrote author Michelle Budig, a professor at the University of Massachusetts at Amherst. “Employers may discriminate against mothers by assuming lower work commitment or performance.”

Beyond employer misconceptions, she wrote, a gender leave gap probably contributes to the disparities.

While it’s true more women than men scale back at work to care for children, there’s no evidence suggesting new mothers who continue working full-time are any less productive than their male or childless counterparts. (Another study from the University of Georgia found that some new mothers actually start working more to combat the perception.)

Same goes for working dads who leave the office early to pick up a toddler from day care. Though more American companies are adopting paternity leave benefits, male workers still fear judgment.

More than a third of 1,000 respondents in a new Deloitte survey said taking leave would "jeopardize their position" at work. More than half thought taking advantage of the benefit would reflect a lack of commitment; 41 percent said they worried about losing opportunities on projects.

These attitudes hurt everyone, sociologist Michael Kimmel argued.

In speeches to college students and bankers, Kimmel, founder and director of Stony Brook University’s Center for the Study of Men and Masculinities, says child-rearing responsibilities fall disproportionately on women, who want just as much as men to get ahead in their careers. Men pressured to keep working, meanwhile, are deprived of time to bond with their kids.

“The more egalitarian our relationships, the happier both partners are,” Kimmel said in a Ted Talk. “The more gender equal companies are, the happier their workers. … Young men, especially, have changed enormously. They want to have lives that are animated by terrific relationships with their children.”

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