Couples vow on their wedding days to love one another in sickness and in health, but apparently, that’s not a promise they always keep. A new study published in the Journal of Health and Social Behavior has found that when a wife gets sick, marriages are more likely to end in divorce than “till death do us part.”

Researchers at Iowa State University looked at 2,701 couples over the age of 50 from the Health and Retirement Study, conducted between 1992 and 2010. They wanted to see if a diagnosis of cancer, heart problems, lung disease and/or stroke could potentially affect marital outcomes. And it did, but only for women: A wife’s major illness was associated with a 6 percent higher probability of subsequent divorce, while a husband’s illness had no effect on divorce rates whatsoever.

“This work has gotten a lot of pretty strong personal reactions from individuals that I’ve talked to,” Amelia Karraker, lead author of the study and an assistant professor of human development and family studies at Iowa State University, told The Huffington Post. “People have said, ‘This happened to my friend’ or ‘This happened to me — I got breast cancer and then my husband asked for a divorce.'”

Before you get too depressed, there are some caveats. For one, most divorces occur much earlier in life — around age 30 — than the older demographic of the study’s sample, so wives’ illnesses aren’t necessarily huge drivers of divorce in general. In fact, a 2010 study found that, in younger people, only a husband’s illness is a predictor of divorce.

Also, the recent findings don’t tell us why more couples are getting divorced after wives are diagnosed with major illnesses — the study just tells us that this pattern exists. But the job of caregiver often falls to spouses, which can be stressful for couples. Not to mention, studies have shown that women report feeling more pain and depression after a chronic illness diagnosis, which may also put strain on a marriage.

Another factor this study couldn’t nail down was which spouse initiated the split when a wife is ill. While sick husbands are usually pretty satisfied with the caregiving that their wives provide, wives who are ill tend to be less satisfied with their husbands’ caregiving. Previous studies, mostly dealing with younger demographics, have found that women initiate two-thirds of divorces. So it may not be the case that husbands are high-tailing it out of marriages at the first sign of trouble.

“You could also think of a major illness diagnosis as a turning point for some people,” Karraker said. “It may be that some of these women say, ‘I don’t think this is a good marriage; I’m not happy; I want to do something different,’ and this is just the impetus to do that.”

So try not to despair too much at these findings. Yes, this is a statistically significant phenomenon, but it’s no guarantee that this is the fate of all (or even most) women who get sick. The researcher herself has been married for two years, but she’s not too concerned about the findings; When asked if this study has made her anxious about the future of her own marriage, she laughed, paused and said: “No, no it does not.”

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