​What leads to divorce? It's often about work

Last Updated Jul 28, 2016 10:16 AM EDT

Here's some fresh insight into the economic factors that predict a successful marriage.

For women today, the takeaway is: Do your thing. Women who work outside the home and take on fewer household responsibilities are no more likely to jeopardize their marriage than those who fulfill a more traditional homemaker role.

But for men: You better work. Men without full-time jobs outside the home are more likely to see their marriages end in divorce. Men today also are expected to contribute more toward household chores, though wives on average shoulder about 70 percent of the load.

These are some of the results of a new study that crunches data on more than 6,300 different-sex couples. Conducted by Harvard sociology professor Alexandra Killewald, the study found that neither a couple's overall financial condition nor a wife's individual ability to support herself can reliably predict whether a marriage will endure.

The division of labor among married couples is another story -- and one that has changed over the years.

Couples married before 1975 saw the risk of divorce go down as a woman's share of household work went up. But for couples married after that time, a more equitable share of in-home chores no longer correlates with a higher risk of divorce.

Yet a man's employment remains a critical predictor of marital stability.

"While contemporary wives need not embrace the traditional female homemaker role to stay married, contemporary husbands face higher risk of divorce when they do not fulfill the stereotypical breadwinner role," Killewald wrote in a statement about the study, which is set to be featured in the August issue of American Sociological Review.

One reason a man's unemployment might inflict more strain on a marriage is that being jobless in the man's case is more likely to be involuntary, the study noted. Additional research is needed, Killewald suggested, particularly looking at couples where the woman is the primary breadwinner by choice.

The study, which was supported by a grant from the William F. Milton Fund and used data from the University of Michigan's Panel Study of Income Dynamics, could have public-policy implications. It shows, for instance, that public-assistance programs such as earned income tax credits and the Supplemental Nutrition Assistance Program (SNAP), are unlikely to boost divorce rates by giving poor women more economic stability.

For women across the economic spectrum, there's no evidence that entry into the workforce comes at the expense of stable marriages. Some had speculated that rising divorce rates -- about 50 percent of U.S. marriages end that way, up from 30 percent in the 1960s -- are a symptom of increasing economic independence among women who no longer need a committed partner for a stable life.

Killewald said her study doesn't find "any tradeoff of that kind."

"Often when scholars or the media talk about work-family policies or work-family balance, they focus mostly on the experience of women," Killewald wrote. "My results suggest one way that expectations about gender and family roles and responsibilities affect men's lives, too: men who aren't able to sustain full-time work face heightened risk of divorce."