“When the economy is bad and people are uncomfortable about their financial future, they tend to postpone having children,” said Andrew Cherlin, a sociology professor at Johns Hopkins University. “We saw that in the Great Depression the 1930s, and we’re seeing that in the Great Recession today.”

“It could take a few years to turn this around,” he added.

The birthrate dipped below 20 per 1,000 people in 1932 and did not rise above that level until the early 1940s. Recent recessions, in 1981-82, 1990-91 and 2001, all were followed by small dips in the birthrate, according to the agency’s figures.