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Back in 2007, America was experiencing a mini-baby boom. The recession brought that to a quick halt. As early as 2008, the country saw a significant drop in birth rates. Baby booms and busts do tend to follow economic cycles. But what was surprising was how quickly birth rates cratered, dropping even before it was clear we were in a recession. What was going on here? At the time, demographers and sociologists essentially said that people’s loins or at least their desire to have babies had done a better job at predicting the recession than economists or forecasters.

But a new study from the National Bureau of Economic Research suggests that procreation might not be as good an economic indicator as it was originally thought. Here’s why:

The study, which was conducted by University of Maryland economics professor Melissa Schettini Kearney and PhD candidate Lisa Dettling, looked at housing prices and birth rates in 66 metro areas from 1990 to 2005. What Kearney and Dettling found is that birth rates are highly correlated to housing prices, more so than unemployment rates and other measures of the economy. The authors found that generally rising housing prices led to more babies.

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That is perhaps the opposite of what you would expect. One of the biggest costs of having a child is space. Having a kid or kids generally means you need to get a larger house. So you would expect to see birth rates drop when housing prices rise, as people find that having more children would be more than they can afford. And indeed the professors did find a small drop in birth rates in non-homeowners in cities where housing prices rose rapidly in the early 2000s. But that small drop was outweighed by a larger increase in births from people who already owned a home. Homeowners might have to trade up, too, so why did they act differently? You know how people took out home equity loans to pay for a new car or boat, or just to live beyond their means. Well, Kearney and Dettling believe we were financing baby making as well. People used the rising equity in their homes to finance the cost of having a baby, or perhaps the rising property values gave owners a boost in wealth, at least temporarily, and the perception that they could afford more kids, that non-homeowners didn’t feel. While Kearney and Dettling only looked at housing prices through 2005, their observations held up in the Great Recession. Housing prices are one of the areas of the economy that have yet to turn around. And according to the latest data, birth rates are still dropping as well.

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What does this all have to do with predicting the recession. Well, one of the oddities of the most recent recession is that it was led by housing prices. In fact housing prices started dropping in most parts of the country six months to a year before the actual recession took place. That’s why birth rates dropped before it was clear we were headed for a deep recession. What’s more, many people think it will be a few more years before housing prices recover. That means baby making may be on hold for a while as well.

Stephen Gandel is a senior writer at TIME. Find him on Twitter at @stephengandel. You can also continue the discussion on TIME‘s Facebook page and on Twitter at @TIME.