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If you make more money than your man, it could be bad for his libido!

A new study from Denmark reveals the husbands of female breadwinners are more likely to use erectile dysfunction drugs than guys who make more than their wives.

The research found that even small differences in relative income are associated with large changes in the use of the little blue pill.

What's even worse, the women breadwinners also suffer and have to deal with increased stress and insomnia. Plus, they're probably the ones having to pay for all that Viagra needed!

The study analyzed data on more than 500,000 couples over a 10 year period from 1997 to 2006.

What is also interesting about these findings, in most cases the husband started out making more money than his wife, but the wife overtook him. This suggests that “men who knowingly marry high-earning females suffer no psychological costs from future income comparisons.

What's even more telling, the effect does not exist for unmarried cohabitants.  Suggesting marriage plays a critical role in how men view wage comparison.