Getting hitched can hitch you to a better financial future, or so a slew of data shows.
But after years of using taxpayer money to promote marriage as a way to help single mothers and their kids climb out of poverty, some experts are arguing it's time to try something different.
"We are continuing to spend money on … these healthy-marriage initiatives, and I think the evidence is now clear that these are not effective policies," said Kristi Williams, an associate professor of sociology at The Ohio State University. "So, it's time to start thinking about spending that money in a way that's more likely to help single mothers and their children."
A new briefing paper, written by Williams and released Monday by the Council on Contemporary Families, argues marriages of single mothers are not necessarily beneficial to the women or their children.
Williams points to a study finding that more than half of single moms who married were divorced by ages 35 to 44. In many cases, women who marry and later divorce are worse off financially.
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Her research also found that the children of single mothers who later married did not often have extra physical or psychological advantages when they reached adolescence.
Williams said she saw advantages for children whose biological parents later got and stayed married but noted that's uncommon. A long-running project called Fragile Families found that only 16 percent of the low-income unwed mothers in the study were married to their child's biological father five years after the birth.
The government has long funded efforts—stemming from the welfare reform that began in 1996—to encourage stable marriages and responsible fatherhood.
Williams argues that policymakers might get more bang for the buck with programs to improve the financial futures of young, low-income women. Those include helping to reduce unintended pregnancies and subsidizing child care for children three years old and younger, she said.
About 40 percent of children in the United States are born outside of marriage, up sharply from past decades, according to the latest government data. Single mothers have much higher rates of poverty than married parents, according to the Census Bureau.
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Williams and others say their research has found that, like most Americans, low-income women want to get and stay married. But they hesitate because they are realistic about how challenging it will be to have a successful marriage amid severe economic strain.
"In many ways it's a rational decision, and that's why we [think] that this sort of idea of promoting marriage is sort of misguided," Williams said. "Women, in many ways, are probably more aware than the government of the challenges of having a beneficial marriage."
Bradford Wilcox, director of the National Marriage Project at the University of Virginia, said it's not surprising to find that single mothers who wed are less likely to have a successful marriage than those who get married before having kids.
"They are more likely to have all the attendant problems that ensue when you put the baby carriage before the marriage," he said.
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Still, Wilcox doesn't think that means Americans should just make peace with very high rates of single motherhood. Instead, he said, promoting having a stable marriage before having children should be one tactic in helping the poor improve their financial and personal lives.
"Regardless of your ideological status, we have a crisis in this country when it comes to quality and stability of relationships for poor, working-class [people]," Wilcox said. "Marriage is not a panacea for that crisis, but I would say it's one part of the policy mix."
—By CNBC's Allison Linn. Follow her on Twitter @allisondlinn and Google or send her an email.
