Northeastern University economist Andrew Sum said with the percentage of single mothers eclipsing 50 percent of all births to women under the age of 30 in 2006, the potential concerns for society are growing in kind, The Kansas City (Mo.) Star reported Sunday.

Sum, who heads up the Boston school's Center for Labor Market Studies, said those among the 50.4 percent of 2006 births typically are thrust into a near-financial crisis due to a limited income.

"The inequality of incomes in these families is unbelievable," he said. "Forty percent are poor, or near-poor. A large fraction is dependent on public assistance. Unless the mother is very well-educated and has a bachelor's degree or above, there's a huge fiscal cost to the rest of us."

Missouri resident Sara Bell echoed Sum's findings, telling the Star that having two children on her own while trying to earn a living and a college degree was exhausting.

"There were times when I was like, 'This is why people marry when they have a kid,'" Bell told the newspaper.