The Pew Research Center is releasing today a report on “Breadwinner Moms." The Washington Post sums it up this way:

In a trend accelerated by the recent recession and an increase in births to single mothers, nearly four in 10 families with children under the age of 18 are now headed by women who are the sole or primary breadwinners for their families, according to a report released Wednesday by the Pew Research Center.

The report reveals a sweeping change in traditional gender roles and family life over a few short decades: The number of married mothers who out-earn their husbands has nearly quadrupled, from 4 percent in 1960 to 15 percent in 2011. Single mothers, who are sole providers for their families, have tripled in number, from 7 to 25 percent in the same period.

“The decade of the 2000s witnessed the most rapid change in the percentage of married mothers earning more than their husbands of any decade since 1960,” said Philip Cohen, a University of Maryland sociologist who studies gender and family trends. “This reflects the larger job losses experienced by men at the beginning of the Great Recession. Also, some women decided to work more hours or seek better jobs in response to their husbands’ job loss, potential loss or declining wages.”

First off, this new Pew study contradicts one of old-line feminism’s favorite gimmicks: the so-called wage gap. The Breadwinner Mom study indicates that more women are making the choice to work longer hours and get better jobs and that the result is that many women now out-earn men.

But there is one disturbing trend in the study: single-parent families are becoming more the norm. Most of these single-parent households are headed by an overworked mother, whose earning capacity is still way below that of her married peers. These women earn around $23,000 a year.

“The makeup of single mothers has changed dramatically,” said Wendy Wang, one of the report’s authors. “In 1960, the vast majority of single mothers were divorced, separated or widowed. Only 4 percent were never married. But now, it’s 44 percent.” Now, 40 percent of all births are to single mothers, she added.

This development has profound implications for society—and not just in terms of the economic wellbeing of children. Minority children from single-parent households commit more crimes than their counterparts in mom and dad families.