Women in the United States have significantly increased their labor-force participation since days past. But a new report from Pew Research Center shows that, despite these gains, Americans' view of men as breadwinners hasn't changed.

"While a nearly equal share of men and women say a man needs to be able to provide for his family to be a good husband or partner (72% and 71%, respectively), men are less likely than women to say the same about women," notes researcher Kim Parker.

This finding comes just a month after similar research was done by the University of Illinois—which I wrote about here—that suggests that some mothers' and fathers' psychological wellbeing suffers when their work and family identities conflict with conventional gender roles.

"The results supported the overarching hypothesis: well-being was lower for mothers and fathers who violated gendered expectations about the division of paid labor, and higher for parents who conformed to these expectations," said researcher Karen Kramer.

Ironically, Ivanka Trump just shared with the world this week that she had postpartum depression after the births of each of her three children. Her explanation for why she was depressed was as follows: "It was very—it was a very challenging, emotional time for me because I felt like I was not living up to my potential as a parent or as an entrepreneur and an executive," Trump told Dr. Oz.

Trump's confession is a textbook example of the study from University of Illinois. If a woman who has just given birth feels there's someplace else she needs to be, if something else is pulling at her, of course her well-being will suffer. She can't relax and enjoy her time at home the way a traditional mother can.

Conversely, men's psychological well-being is highest when they're the primary wage-earners. That's because the sexes bring different strengths and desires to the parenting table. There's a reason that even in families where both parents work, 70 percent consist of fathers who earn more than mothers.

It's simple, really. A man's identity is inextricably linked to his job, whereas a woman's is linked (much to feminists' dismay) to children and the home. He takes pride in supporting his family. That's why only a quarter of men from the Pew study say it's "very important" for a woman to be able to support the family financially. Most Americans just don't agree with that.

Knowing these facts about American attitudes can go a long way in relieving the pressure women feel to be and to do it all. We should pay attention.

Suzanne Venker (@SuzanneVenker) is a contributor to the Washington Examiner's Beltway Confidential blog. She is an author, Fox News contributor, and trustee of Leading Women for Shared Parenting. Her fifth book, "The Alpha Female's Guide to Men & Marriage: HOW LOVE WORKS," was published in February.

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