For decades, academics and social scientists have claimed that couples who live together before getting married face a higher risk of divorce. But it's just not true, says Arielle Kuperberg an assistant professor of sociology at the University of North Carolina–Greensboro."Cohabitation does not cause divorce — yay!" she told LiveScience.com, adding the exclamation because about two-thirds of new marriages in the United States today start with shacking up.Previous studies compared the divorced rates of couples who cohabited with those who didn't by using the age of marriage. Kuperberg did something new: She compared the relationships using the date of first moving in together. That date, she reasoned, is when a couple really takes on the roles of marriage, regardless of whether they have a legal certificate.Kuperburg, in research released Monday by the nonpartisan Council on Contemporary Families, found that premarital cohabitation by itself has little impact on a relationship's longevity. Those who began living together, unmarried or married, before the age of 23 were the most likely to later split."Part of it is maturity, part of it is picking the right partner, part of it is that you're really not set up in the world yet," she says. "And age has to do with economics."Indeed, other research released by the Council on Contemporary Families suggests that the longer couples wait to start living together, the better their chances for long-term relationship success. This makes sense to historian Stephanie Coontz, the council's director of research and public education."Marriages require much more maturity than they once did," she says. In the 1950s, husbands and wives stepped into well-defined gender roles. "Nowadays, people come to marriage with independent aspirations and much greater ideas of equality. Maturity is so important, and negotiating skills are so much more important."Virginia Rutter, professor of sociology at Framingham State University in Massachusetts, welcomed Kuperburg's findings."The big message for me is thank goodness there is now really good, clear, unambiguous research that can help us get rid of the 'cohabitation is the issue' approach,'' Rutter told the Christian Science Monitor. "It goes from the easy answer — that life's problems are about character — to the more challenging answer, that life's problems are about context. What are the resources that you are empowered to pull together to create a good life?"Other research included in Monday's report finds that moving in may be fine, but rushing things might have disadvantages. Sharon Sassler, a sociologist at Cornell University, has found that many couples with lower incomes and less education decided to move in together because of financial pressures.Most cohabiters with college degrees move in together only after a long stretch of dating, Sassler says. More than half have been couples for more than a year, with an average of 14 months dating before cohabiting. More than half of the cohabiters without college degrees move in together after less than six months of dating. Sassler argues that it is the type of premarital cohabitation that predicts divorce, not necessarily cohabitation in itself.Besides age, another predictor of divorce is when couples have children before even moving in together. According to Kuperberg, couples who had a child pre-cohabitation had a 57 percent higher likelihood of splitting when compared to couples who didn't have a child before moving in together.