This change in marriages is the biggest catalyst driving divorces...
Bottom Line: You're likely well aware that money issues are far and away the top reasons cited for divorce (with over half of all marriages ending due to financial issues/divisions). Typically, it's financial stress driven by income loss, trouble making ends meet with a growing family, differences in financial priorities, etc. The latest study shows that the fastest growing financial catalyst for divorce is essentially the inverse.
While women now represent half of the workforce (and have since the recession as more jobs were lost in traditional male industries – financial, manufacturing, construction, etc.) many are surging past their husbands in their careers. There are a number of factors that likely contribute to this (more career-oriented women, smaller family size, and more college educated women than men) significant shift. While surging careers generally mean surging salaries – the outcomes in many marriages isn't necessary as positive.
The study entitled "All the Single Ladies: Job Promotions and the Durability of Marriage" found that women who begin a marriage earning less than a husband but end up passing the earnings of their husbands are more likely to become divorced than if the typical income roles remained static throughout the marriage.
There are a few likely contributing factors. The first is probably the most obvious – ego. Simply put, research has shown that most men feel responsible for traditional gender roles in a marriage. When they're no longer the primary bread-winner that can take a toll emotionally on a proud husband. That being said the bigger catalyst is when the husband must make career concessions to accommodate the more successful wife. The biggest of those concessions ID'd – having to relocate for the career of the wife. It's easy to see how that might create tension in a marriage if it's a surprise to the husband.
Once again this gets back to communication early and often prior to and during your marriage. Previous research has shown that couples who agree to a financial plan prior to marriage are about 70% less likely to become divorced. Adding career aspirations of both of you to that plan would appear to be increasingly important.