A recent study from the American Association of University Women found that women hold almost two-thirds ($833 billion) of the country's roughly $1.3 trillion of student debt. Men, by comparison, hold just $477 billion.
One reason for this imbalance is that roughly 56 percent of college students are women. A second factor is the gender wage gap, which can make it more difficult for women to pay off their loans.
But what may be the biggest contributing factor is an unexpected one: American families are willing to spend more on their sons' educations than they are on their daughters'.
The Wall Street Journal points to two recent studies that found that families save more for boys to go to college than they do for girls.
The first study, conducted by T. Rowe Price, analyzed information from 238 households, and found that 50 percent of households with only boys had money saved for college but just 35 percent of households with only girls did. Eighty-three percent of boy-only households contributed to college savings accounts monthly, compared to just 70 percent of girl-only households.
Boy-only households were also more willing to take on debt, more likely to send their sons to expensive colleges and more likely to cover the entire cost of college.
Roger Young, a senior financial planner with T. Rowe Price, tells CNBC, "Looking at the breadth of the results, it suggests there are some antiquated viewpoints on gender out there."
In order to avoid these biases, Young suggests parents review their college savings approach to ensure they're being fair to each child. "Just take a hard look at your level of financial commitment and make sure you're not short-changing your girls," he says.
In a second study, private student loan provider LendEDU polled over 1,400 college grads and found that 6 percent of women said that their parents paid for the majority of college, compared to 10 percent of men who said their parents footed the bill. The same study found that 50 percent of women claimed that their parents had paid nothing for their education, compared to 43 percent of men.
Steven Roy Goodman, an educational consultant and admissions strategist, tells Cheryl Winokur Munk of The Wall Street Journal that the clearest explanation for this phenomena is gender bias.
"There is really no way to say this subtly: The parents had different life expectations for their sons and daughters — and were unwilling to pay private college tuitions for their daughters," says Goodman. "They perceived that the young women were not going to have 40-year careers in the ways they expected their sons to have."
But Shaun Harper, a professor of education and business at the University of Southern California and executive director of the USC Race and Equity Center says there could be an alternative reason for this college savings gap: Parents expect girls to win more scholarship money, since girls typically outperform boys in school.
"Many parents are probably not convinced their boys are going to receive enough merit-based scholarship money," he says.
But The Wall Street Journal points out that according to the National Center for Education Statistics, a similar percentage of girls earn merit-based scholarships as boys. Furthermore, the size of the average merit-based grant was actually higher for boys than it was for girls ($6,500 compared to $6,100.)
Shereem Herndon-Brown, former admissions officer at Georgetown University, agrees with Goodman. "I don't think parents are going to admit to their 18-year-old daughter that they don't want to pay as much for her education because they are thinking 10 years down the road to her wedding," he tells The Wall Street Journal, "but it's an unfortunate reality."
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