Americans are having fewer babies. At first, researchers thought the declining fertility rate was because of the recession, but it kept falling even as the economy recovered. Now it has reached a record low for the second consecutive year.

Because the fertility rate subtly shapes many major issues of the day — including immigration, education, housing, the labor supply, the social safety net and support for working families — there's a lot of concern about why today's young adults aren't having as many children. So we asked them.

Wanting more leisure time and personal freedom; not having a partner yet; not being able to afford child-care costs — these were the top reasons young adults gave for not wanting or not being sure they wanted children, according to a new survey conducted by Morning Consult for the New York Times.

About a quarter of the respondents who had children or planned to said they had fewer or expected to have fewer than they wanted.

The survey tells a story of economic insecurity. Young people have record student debt, many graduated in a recession and many can't afford homes — all as parenthood has become more expensive. Women in particular pay an earnings penalty for having children.

"We want to invest more in each child to give them the best opportunities to compete in an increasingly unequal environment," said Philip Cohen, a sociologist at the University of Maryland who studies families and has written about fertility.

At the same time, he said, "There is no getting around the fact that the relationship between gender equality and fertility is very strong: There are no high-fertility countries that are gender equal."

The vast majority of women in the United States still have children. But the most commonly used measure of fertility, the number of births for every 1,000 women of childbearing age, was 60.2 last year, a record low. The total fertility rate — which estimates how many children women will have based on current patterns — is down to 1.8, below the replacement level in developed countries of 2.1.

In the survey, more than half of the 1,858 respondents — a nationally representative sample of men and women ages 20 to 45 — said they planned to have fewer children than their parents. About half were already parents. Of those who weren't, 42 percent said they wanted children, 24 percent said they did not and 34 percent said they weren't sure.

Jessica Boer, 26, has a long list of things she'd rather spend time doing than raising children: being with her family and her fiancé; traveling; focusing on her job as a nurse; getting a master's degree; playing with her cats.

"My parents got married right out of high school and had me and they were miserable," said Boer, who lives in Portage, Mich. "But now we know we have a choice."