The researchers collected data on prior romantic experiences, whether the relationship started by “hooking up” in a casual relationship, whether the couple had a big or small wedding, and what the overall quality of the marriage was.

Notably, they found that the decisions and experiences with others before marriage had a lasting effect on the relationship. In the study group, most people had had sex before marriage, reporting an average of five sexual partners. But 23 percent of the subjects had only one sexual partner, their eventual spouse. Those individuals reported higher marriage quality than people who had had multiple sexual partners.

People who lived with another person before marrying also reported a lower-quality relationship. In that group, 35 percent had higher-quality marriages. Among those who had not lived with another romantic partner before marriage, 42 percent had higher-quality marriages.