The baby boom some expected to occur after months of romantic partners quarantining at home together has failed to materialize, according to researchers at the Brookings Institution.

Rather, it’s quite the opposite: Melissa Kearney and Phillip Levine, economics professors at the University of Maryland and Wellesley College, respectively, say they expect 300,000 fewer births in 2021, in what they’re calling a COVID “baby bust.”

Their finding is based in part on evidence that shows a 1% increase in the national unemployment rate corresponds with an equivalent 1% drop in birth rates. In order to account for the fact that there is a public health crisis layered on top of an economic one, Kearney and Levine examined the impact of the 1918 Spanish flu on births, finding that spikes in flu deaths resulted in a decrease in the number of births nine months later.

These effects can be observed on both the macro and micro level: “There is a well-documented cycle to the nation’s birthrate: When the labor market is weak, aggregate birth rates decline; when the labor market improves, birth rates improve,” Kearney and Levine wrote in a New York Times op-ed on their research. “At the individual level, there is also a well-documented link between changes in income and births: When income increases, people often expand their families; when people experience job or income loss, they have fewer children.”

Kearney and Levine made a similar estimate in June, just a few months into the pandemic, writing in a Brookings report that myths about baby booms following snowstorms and blackouts were largely that—myths. This early prediction was also buoyed by findings from the Guttmacher Institute the same month, which detailed dramatic shifts in the way women were thinking about family planning during the pandemic.

The study found that more than 40% of women said they were altering their plans for when to have children or how many children they would have, and more than one-third of women said the pandemic had made them decide to delay pregnancy or have fewer children. Just 17% of respondents reported wanting to have children sooner or to have more of them because of the pandemic.

A certain amount of common sense dictates that this must be the case. Women have suffered some of the highest rates of unemployment in recent months, and mothers especially have been effectively pushed out of the workforce because of school closures and lapses in childcare.

This is only an acute symptom of a much larger problem. Birth rates have been falling in the United States for years now, the result of a confluence of social, cultural, and economic factors that have made childbearing less desirable for many people. The most obvious among these factors is the lack of government support for parents: The U.S. continues to be the only industrialized country that doesn’t have a universal paid family leave policy in place. It also lacks both universal childcare and preschool policies, which can make it more feasible for people to have children.

Kearney and Levine say it’s possible birth rates will begin to rebound to pre-pandemic numbers, since some people are delaying pregnancy, not abandoning the desire to have children altogether. But the longer the pandemic—and the social and economic conditions created by it—go on, the less that may be true, which could lead to long-term consequences, like a shrinking workforce.

“As of now, we stand by our prediction of a COVID baby bust of around 300,000 fewer births,” they report. “But the longer the pandemic lasts, and the deeper the economic and social anxiety runs, it is feasible that we will see an even larger reduction in births with an increasing share of them averted permanently.”