Foreign-Born Mothers Raising US Birth Rate, Study Finds

Creatas Images/Thinkstock(NEW YORK) — Foreign-born mothers living in the U.S. are driving long term population growth, according to a new report by Pew.

While overall the number of babies being born in the U.S. increased from 3.74 million to four million, the uptick is largely due to the number coming from foreign-born mothers in the U.S., which grew three-fold. Births from U.S.-born mothers decreased.

Pew found that, as of 2014, “23% of all babies born in the U.S. had immigrant mothers, up from just 7% in 1970.”

In 1970, there were 3.46 million births to U.S. born women and a population of about 203 million, versus 3.1 million in 2014 and a total population of about 323 million.

“Almost one-quarter of births are to women who were not born in this country,” Gretchen Livingston, senior researcher at Pew Research Center and the lead author of the report, told ABC News.

“In the long term, overall births annually in the U.S. would have been on the decline,” she said. “Had there not been immigrant moms coming in, births would have actually dropped.”

The researchers also found that, of the 23 percent of babies born to immigrant mothers, roughly one-third were to undocumented immigrant mothers and the other two-thirds were in the U.S. on legal status. That works out to 7 percent of all U.S. births from undocumented immigrant mothers — down from 2007, when they peaked at 9 percent of all U.S. births that year, or 370,000 babies.

The vast majority of foreign-born new mothers have been in the U.S. long term, more than 11 years, according to the study.

The researchers didn’t break down how long the undocumented immigrant mothers had been living in the U.S., but point to a September report that found the vast majority of the undocumented population have been in the U.S. for more than 10 years.

“We are not seeing evidence of women crossing the border to have babies. This is not who the unauthorized immigrant population is,” Jeffrey S. Passel a senior demographer at Pew Research Center told ABC News. “Its people who have been here a long time.”

The researchers also found that births outside of marriage declined for immigrant mothers — largely due to a change in the origin regions of immigrants in the U.S.

A rising share of foreign-born mothers originated in Asian countries, where births outside of marriage are quite low compared to births from Latin American mothers.

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