Divorce rates in the US continue to rise among those who have a poor educational background, new research from the University of Maryland has found.

While the average divorce rate in America peaked thirty years ago and has declined slightly since then, this latest study shows that this is not true for all sections of society. A woman’s likelihood of divorcing within ten years of her first marriage rose irrespective of her level of education until the mid-1970s.

After that, however, divorce rates diverged. Twenty-nine percent of women with a four-year college degree who married between 1975 and 1979 divorced within a decade; among college-educated women who married between 1990 and 1994, the within-ten-years divorce rate had fallen to 16.5 percent.

Among women who completed secondary education without going further, however, the divorce rate remained roughly constant over the same period, and it rose among women without a high-school diploma.

According to the study, this divergence might be both a consequence and a cause of America’s growing economic inequality. Economic disadvantages can make divorce more likely, and divorce in turn creates further personal and financial difficulties for parents and children alike, which threaten to “perpetuate inequality across generations.”