Being a child of divorce nearly halves the likelihood that a young person will earn a bachelor’s or graduate degree compared to someone whose parents remain married, new research suggests.

Determining exactly why will take more digging.

Researchers at Iowa State University analyzed 15 years of data from the National Longitudinal Survey of Youth 1997, a U.S. Labor Department survey that studies young people born in the early 1980s. The most recent iteration looked at their outcomes at ages 26 to 32.

The Iowa State researchers found that just 27 percent of young people with divorced parents had a bachelor’s degree or higher, compared to 50 percent of those with married parents. Looking just at advanced degrees, they found that the split was also wide: 12 percent of young people with divorced parents had or were working toward a graduate or professional degree, compared to 20 percent whose parents were married.

Susan Stewart, an Iowa State sociology professor and one of the researchers, said in an interview that the new findings show that while children of divorce are disadvantaged when it comes to completing a bachelor's degree, divorce hinders young people “even beyond just a four-year degree.”

Causes for the difference in attainment aren’t exactly clear since research shows that married and divorced parents have similar educational expectations for their kids. But the survey also found that married parents were more educated than divorced parents.

Stewart said income may also be a factor: in most divorces, parents’ incomes take a hit, and most divorce settlements are silent on how families will pay for college. She and fellow researchers suggest that future agreements should consider how parents will support their children after age 18.

But income is not necessarily the primary driver, she said. Researchers should also consider a student’s self-concept: “Sometimes children of divorce don’t feel as entitled to go to college,” she said. “They feel ‘lesser’ somehow.”

More data is needed to find out exactly what’s at play, she said. “There are so many directions for future research to kind of find all of this out.”

The new study appears in the Journal of Family Issues.