The recession was accompanied by a sharp increase in the number of American men who underwent vasectomies, according to research presented Monday, though it’s unclear if economic woes actually led to more procedures.

Researchers from Weill Cornell Medical College looked at survey data from the National Survey for Family Growth, which interviewed more than 10,000 men between 2006 and 2010, according to the American Society for Reproductive Medicine. They wanted to get a sense of how the economic downturn from 2007 to 2009 affected men’s decisions about having kids.

Before the recession, 3.9% of men reported having a vasectomy, but 4.4% reported having one afterward, which the researchers calculated to mean an additional 150,000 to 180,000 vasectomies during each year of the recession.

The researchers also found after the recession that men were less likely to be employed full-time, and more likely to have lower incomes and be without health insurance. Nothing changed when it came to men’s desire to have children, but those who were interviewed after the recession were more likely to want fewer children.

It’s important to note that the study, which is being presented at the American Society for Reproductive Medicine’s 70th Annual Meeting, does not prove causation, meaning it’s unclear whether men were undergoing surgery for financial reasons. Though the researchers do conclude that their findings suggest Americans may be factoring economics into family planning—which is not necessarily a new trend.

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