The Hidden Agenda of the Political Mind: How Self-Interest Shapes Our Opinions, And Why We Won't Admit It, by Jason Weeden and Robert Kurzban discusses ways people differ, and the effect it has on their voting behavior. One way people differ is in sexual behavior. Some people enjoy casual sex and sexual variety, and have little or no interest in getting married. The authors call these people "Freewheelers." Other people are the opposite. The authors call these people "Ring Bearers."
The authors get their data on sexual behavior and preference from the U.S. General Social Survey, combining years 2002 to 2012. There were 16, individuals in this study. According to this study:
"for those who had prior sex partners and who lived together before getting engaged, the ten-year divorce rate is over 40%; among those where virgins until around the time they married, the ten-year diverse rate is tiny, less than 15%."
The authors also write:
"39% of American adults are Freewhelers, 34% are Ring Bearers, and 27% are in the middle."
Although the authors do not point this out, plenty of evidence exists that children who are raised to adulthood by both biological parents living together in matrimony tend to have many fewer problems in life than other children.