London School of Economics and Political Science found that women whose marriages are on the brink of collapse work more hours as an insurance against divorce.
For every 1% increase in the risk of marital breakdown, women work an extra 12 minutes per week.
Berkay Ozcan and his co-researchers used the legalization of divorce in Ireland in 1996 to determine how subsequent marriage breakdown rates affected women's participation in the workforce.
They found that following the legalization, non-religious married women increased how much they worked by around 18%, compared to religious married women.
Religious women were used as a control group by the researchers because they were not affected by the new divorce law, their rate of separation remained constant and their divorce rate is marginal.
Dr Ozcan said: "We see that women who are at a higher risk of divorce significantly increase how much they work. And it isn't that women working outside the home are more likely to get divorced. Rather, faced with a rising probability of divorce, women work more, whether they ultimately separate or not. They are working as a form of insurance in case of divorce or in anticipation of it."
Dr Ozcan also said his research found women's increased work outside the home was not compensated by either a decrease in domestic time spent on childcare or an increase in child-rearing by fathers.
"Women who have secured their outside options, in case of divorce, may have done so, at least in the short run, at the expense of their leisure time and potentially their well-being."
The study published in the European Economic Review found there was no strong evidence that men worked longer with the increased risk of divorce.