As a result, in 2011, the American birthrate hit a record low, with 63 births per 1,000 women ages 15 to 44, led by the decline in births to immigrant women. The national birthrate is now about half what it was during the baby boom years, when it peaked in 1957 at 122.7 births per 1,000 women of childbearing age.

The decline in birthrates was steepest among Mexican-American women and women who immigrated from Mexico, at 25.7 percent. This has reversed a trend in which immigrant mothers accounted for a rising share of births in the United States, according to a recent report by the Pew Research Center. In 2010, birthrates among all Hispanics reached their lowest level in 20 years, the center found.

The sudden drop-off, which coincided with the onset of the recession, suggests that attitudes have changed since the days when older generations of Latinos prized large families and more closely followed Roman Catholic teachings, which forbid artificial contraception.

Interviews with young Latinas, as well as reproductive health experts, show that the reasons for deciding to have fewer children are many, involving greater access to information about contraceptives and women’s health, as well as higher education.

When Marucci Guzman decided to marry Tom Beard here seven years ago, the idea of having a large family — a Guzman tradition back in Puerto Rico — was out of the question.

“We thought one, maybe two,” said Ms. Guzman Beard, who gave birth to a daughter, Attalai, four years ago.

Asked whether Attalai might ever get her wish for a little brother or sister, Ms. Guzman Beard, 29, a vice president at a public service organization, said: “I want to go to law school. I’m married. I work. When do I have time?”

The decisions were not made in a vacuum but amid a sputtering economy, which, interviewees said, weighed heavily on their minds.

Latinos suffered larger percentage declines in household wealth than white, black or Asian households from 2005 to 2009, and, according to the Pew report, their rates of poverty and unemployment also grew more sharply after the recession began.

Prolonged recessions do produce dips in the birthrate, but a drop as large as Latinos have experienced is atypical, said William H. Frey, a sociologist and demographer at the Brookings Institution. “It is surprising,” Mr. Frey said. “When you hear about a decrease in the birthrate, you don’t expect Latinos to be at the forefront of the trend.”

D’Vera Cohn, a senior writer at the Pew Research Center and an author of the report, said that in past recessions, when overall fertility dipped, “it bounced back over time when the economy got better.”

“If history repeats itself, that will happen again,” she said.

But to Mr. Frey, the decrease has signaled much about the aspirations of young Latinos to become full and permanent members of the upwardly mobile middle class, despite the challenges posed by the struggling economy.

Jersey Garcia, a 37-year-old public health worker in Miami, is in the first generation of her family to live permanently outside of the Dominican Republic, where her maternal and paternal grandmothers had a total of 27 children.

“I have two right now,” Ms. Garcia said. “It’s just a good number that I can handle.”

“Before, I probably would have been pressured to have more,” she added. “I think living in the United States, I don’t have family members close by to help me, and it takes a village to raise a child. So the feeling is, keep what you have right now.”