Sociologists have known for years that in heterosexual marriages, women are more likely than men to opt for divorce, with data suggesting that some two-thirds of divorces were initiated by the wives. What sociologists haven't understood is why; many proposed that women are more attuned to difficulties in relationships, and thus, more likely to end them. In a new paper, " Who Wants The Breakup? Gender And Breakup in Heterosexual Couples ," Stanford University associate professor of sociology Michael J. Rosenfeld examined that belief. He analyzed surveys of 2,262 adults, ages 19 to 94, who had opposite-sex partners (both marital and non-marital) in 2009. Of the 2,262 study participants, 371 had split up with or divorced their partners by 2015, with 69% of divorces initiated by women — par for the established-wisdom course. Here's where things got interesting: Women and men initiated breakups outside of marriage at the same rate (whether they were cohabiting or not), turning the assumption that women are more easily dissatisfied in relationships on its head. "I assumed, and I think other scholars assumed, that women's role in breakups was an essential attribute of heterosexual relationships," Rosenfeld commented , "but it turns out that women's role in initiating breakups is unique to heterosexual marriage." Rosenfeld found that women and men in non-marital relationships report the same levels of relationship quality, but wives report significantly lower levels of relationship quality than husbands. "Neither women’s supposedly greater sensitivity to relationship problems, nor income gaps, nor education gaps, nor conservative religious identity" could explain why wives were more prone to bow out of marriages than husbands. The remaining culprit: the institution of marriage itself. Free as they are of "historical baggage" and "expectations," Rosenfeld posits, non-marital unions are more likely to meet both couples' needs; while on the other hand, "Wives still take their husbands' surnames, and are sometimes pressured to do so. Husbands still expect their wives to do the bulk of the housework and the bulk of the childcare." In his opinion, it's not women's mythical "sensitivity" that's to blame for the dissolution of marriages, then, but rather marriage's slowness to evolve to meet the needs of both spouses — or the gender roles by which married couples establish their relationship dynamics. As our attitudes toward marriage continue to develop, hopefully fewer and fewer women will be required to break free of a person to rid themselves of heteronormativity.