"This rise … represents the reversal of a long-term decline in 'stay-at-home' mothers that had persisted for the last three decades of the 20th century," Pew reported. "The recent turnaround appears to be driven by a mix of demographic, economic and societal factors, including rising immigration as well as a downturn in women's labor force participation, and is set against a backdrop of continued public ambivalence about the impact of working mothers on young children."

The survey showed that the uptick meant more moms were staying at home with their kids.

While conventional wisdom once supported this arrangement, by the mid-1990s, Pew found that 70 percent of the general public believed a working mom "can establish just as warm and secure a relationship with her children" as the stay-at-home mom. That percentage has held up since 2008, Pew said.

At the same time, when asked whether it is better to have a parent at home with children rather than working, 60 percent agreed that it was. So apparently Americans believe you can love your kids to death if you work, but you still can't parent as effectively if no parent stays home.

Looking at the education of stay-at-home women, Pew found that a quarter of today's stay-at-home moms had college degrees, compared to 7 percent in 1970.

About one in five today is not a high school grad, compared to 35 percent in 1970. Comparing working moms with those not in the workforce, 30 had a high school degree or less, while 49 percent of those at home had a high school degree or less.

"In addition, stay-at-home mothers are less likely than working mothers to be white (51 percent are white, compared with 60 percent of working mothers) and more likely to be immigrants (33 percent vs. 20 percent). The overall rise in the share of U.S. mothers who are foreign-born, and rapid growth of the nation's Asian and Latino populations, may account for some of the recent increase in the share of stay-at-home mothers," Pew said.

Pew also segmented the data by "elite" stay-at-home women, those from relatively affluent households. Here's what it reported in this regard:

"In 2012, nearly 370,000 U.S. married stay-at-home mothers (with working husbands) had at least a master's degree and family income exceeding $75,000. This group accounted for 5 percent of married stay-at-home mothers with working husbands.

"These affluent stay-at-home mothers, who have a median family income of nearly $132,000, are somewhat older than married stay-at-home mothers with working husbands overall, according to 2011-2012 data. Half are ages 35-44, while just 19 percent are younger than 35. As is true of all married stay-at-home mothers, about half of this elite group (53 percent) has at least one child age 5 or younger at home.

"These women stand out from other married stay-at-home mothers in that they are disproportionately white or Asian. About seven-in-10 (69 percent) are white, and fully 19 percent are Asian. Only 7 percent are Hispanic, and 3 percent are black."

Commenting on the data, Pew opined:

"The largest share consists of 'traditional' married stay-at-home mothers with working husbands. … The economic ups and downs of the past decade likely influenced mothers' decisions on whether to stay home or go to work. The share of mothers staying home with their children rose from 2000 to 2004, but the rise stopped in 2005, amid economic uncertainty that foreshadowed the official start of the Great Recession in 2007.

"The increase in both number and share eventually resumed: From 2010 to 2012, the share of stay-at-home mothers (29 percent) was 3 percentage points higher than in 2008 (26 percent), at the height of the recession.

"A growing share of stay-at-home mothers (6 percent in 2012, compared with 1 percent in 2000) say they are home with their children because they cannot find a job.

"With incomes stagnant in recent years for all but the college-educated, less educated workers in particular may weigh the cost of child care against wages and decide it makes more economic sense to stay home."